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Sample records for metal hydroxide waste

  1. Characteristics of Cement Solidification of Metal Hydroxide Waste

    Directory of Open Access Journals (Sweden)

    Dae-Seo Koo

    2017-02-01

    Full Text Available To perform the permanent disposal of metal hydroxide waste from electro-kinetic decontamination, it is necessary to secure the technology for its solidification. The integrity tests on the fabricated solidification should also meet the criteria of the Korea Radioactive Waste Agency. We carried out the solidification of metal hydroxide waste using cement solidification. The integrity tests such as the compressive strength, immersion, leach, and irradiation tests on the fabricated cement solidifications were performed. It was also confirmed that these requirements of the criteria of Korea Radioactive Waste Agency on these cement solidifications were met. The microstructures of all the cement solidifications were analyzed and discussed.

  2. Waste metal hydroxide sludge as adsorbent for a reactive dye.

    Science.gov (United States)

    Santos, Sílvia C R; Vílar, Vítor J P; Boaventura, Rui A R

    2008-05-30

    An industrial waste sludge mainly composed by metal hydroxides was used as a low-cost adsorbent for removing a reactive textile dye (Remazol Brilliant Blue) in solution. Characterization of this waste material included chemical composition, pH(ZPC) determination, particle size distribution, physical textural properties and metals mobility under different pH conditions. Dye adsorption equilibrium isotherms were determined at 25 and 35 degrees C and pH of 4, 7 and 10 revealing reasonably fits to Langmuir and Freundlich models. At 25 degrees C and pH 7, Langmuir fit indicates a maximum adsorption capacity of 91.0mg/g. An adsorptive ion-exchange mechanism was identified from desorption studies. Batch kinetic experiments were also conducted at different initial dye concentration, temperature, adsorbent dosage and pH. A pseudo-second-order model showed good agreement with experimental data. LDF approximation model was used to estimate homogeneous solid diffusion coefficients and the effective pore diffusivities. Additionally, a simulated real effluent containing the selected dye, salts and dyeing auxiliary chemicals, was also used in equilibrium and kinetic experiments and the adsorption performance was compared with aqueous dye solutions.

  3. Alkali metal and alkali metal hydroxide intercalates of the layered transition metal disulfides

    International Nuclear Information System (INIS)

    Kanzaki, Y.; Konuma, M.; Matsumoto, O.

    1981-01-01

    The intercalation reaction of some layered transition metal disulfides with alkali metals, alkali metal hydroxides, and tetraalkylammonium hydroxides were investigated. The alkali metal intercalates were prepared in the respective metal-hexamethylphosphoric triamide solutions in vaccuo, and the hydroxide intercalates in aqueous hydroxide solutions. According to the intercalation reaction, the c-lattice parameter was increased, and the increase indicated the expansion of the interlayer distance. In the case of alkali metal intercalates, the expansion of the interlayer distance increased continuously, corresponding to the atomic radius of the alkali metal. On the other hand, the hydroxide intercalates showed discrete expansion corresponding to the effective ionic radius of the intercalated cation. All intercalates of TaS 2 amd NbS 2 were superconductors. The expansion of the interlayer distance tended to increase the superconducting transition temperature in the intercalates of TaS 2 and vice versa in those of NbS 2 . (orig.)

  4. Aging of trivalent metal hydroxide/oxide gels in divalent metal salt ...

    Indian Academy of Sciences (India)

    Unknown

    Aging of trivalent metal hydroxide/oxide gels in divalent metal salt solutions: Mechanism of formation of layered double hydroxides (LDHs). A V RADHA and P ..... This situation promotes coprecipitation of the two metal hydroxides, by virtue of which the titrations yield the. Zn–Al LDH. The LDHs isolated before and after ...

  5. Single sheet metal oxides and hydroxides

    DEFF Research Database (Denmark)

    Huang, Lizhi

    The synthesis of layered double hydroxides (LDHs) provides a relatively easy and traditional way to build versatile chemical compounds with a rough control of the bulk structure. The delamination of LDHs to form their single host layers (2D nanosheets) and the capability to reassemble them offer ......) Delamination of the LDHs structure (oxGRC12) with the formation of single sheet iron (hydr)oxide (SSI). (3) Assembly of the new 2D nanosheets layer by layer to achieve desired functionalities....

  6. Production of calcium hydroxide from the waste of Cariri stone

    International Nuclear Information System (INIS)

    Alves, T.M.E.; Santos, A.M.M.; Brasileiro, M.I.; Pinheiro, S.F.L.; Prado, A.C.A.

    2016-01-01

    The extraction of Cariri stone in the northeast is a frequent activity because of its ornamental application as well as for the construction sector. However, by this extraction, untapped waste formation grows and becomes a problem for the environment. The objective of this work is to produce calcium hydroxide, from this limestone residue, with controlled porosity, solubility and particle size. The waste was characterized with X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF) and thermal analysis (TGA). The limestone was calcined at 850°C and 950°C for 45 minutes and three hours, being characterized by XRD, XRF and TGA. Once calcined, it was hydrated with 17,5g and 22g oxide to 100mL water and manually mixed for 15 and 25 minutes. The calcium hydroxides have been submitted for tests in vivo in rats and will be characterized by XRD, Scanning Electron Microscopy (SEM) and Infrared. (author)

  7. Superconductivity and magnetism in iron sulfides intercalated by metal hydroxides.

    Science.gov (United States)

    Zhou, Xiuquan; Eckberg, Christopher; Wilfong, Brandon; Liou, Sz-Chian; Vivanco, Hector K; Paglione, Johnpierre; Rodriguez, Efrain E

    2017-05-01

    Inspired by naturally occurring sulfide minerals, we present a new family of iron-based superconductors. A metastable form of FeS known as the mineral mackinawite forms two-dimensional sheets that can be readily intercalated by various cationic guest species. Under hydrothermal conditions using alkali metal hydroxides, we prepare three different cation and metal hydroxide-intercalated FeS phases including (Li 1- x Fe x OH)FeS, [(Na 1- x Fe x )(OH) 2 ]FeS, and K x Fe 2- y S 2 . Upon successful intercalation of the FeS layer, the superconducting critical temperature T c of mackinawite is enhanced from 5 K to 8 K for the (Li 1- x Fe x OH) δ + intercalate. Layered heterostructures of [(Na 1- x Fe x )(OH) 2 ]FeS resemble the natural mineral tochilinite, which contains an iron square lattice interleaved with a hexagonal hydroxide lattice. Whilst heterostructured [(Na 1- x Fe x )(OH) 2 ]FeS displays long-range magnetic ordering near 15 K, K x Fe 2- y S 2 displays short range antiferromagnetism.

  8. Aging of iron (hydr)oxides by heat treatment and effects on heavy metal binding

    DEFF Research Database (Denmark)

    Sørensen, Mette Abildgaard; Starckpoole, M. M.; Frenkel, A. I.

    2000-01-01

    Amorphous iron (hydr)oxides are used to remove heavy metals from wastewater and in the treatment of air pollution control residues generated in waste incineration. In this study, iron oxides containing heavy metals (e.g., Pb, Hg, Cr, and Cd) were treated at 50, 600, and 900 °C to simulate...... oxides were transformed to hematite, which had a greater thermodynamic stability but less surface area than the initial products. Heat treatment also caused some volatilization of heavy metals (most notably, Hg). Leaching with water at pH 9 (L/S 10, 24 h) and weak acid extraction showed that heat...... of iron oxides may be advantageous to improve the thermodynamic stability of the product but that thermal treatment at both 600 and 900 °C significantly reduced the binding capacity for heavy metals....

  9. Vitrified metal finishing wastes

    Energy Technology Data Exchange (ETDEWEB)

    Bingham, P.A. [Immobilisation Science Laboratory, Department of Engineering Materials, University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom)]. E-mail: p.a.bingham@sheffield.ac.uk; Hand, R.J. [Immobilisation Science Laboratory, Department of Engineering Materials, University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom)

    2005-03-17

    Durable phosphate glasses were formed by vitrifying waste filter cakes from two metal finishing operations. Some melts formed crystalline components during cooling. Compositional analysis of dried, heat treated and vitrified samples was made using energy-dispersive X-ray spectroscopy, X-ray fluorescence spectroscopy, inductively-coupled plasma spectroscopy and Leco induction furnace combustion analysis. Hydrolytic dissolution, measured by an adapted product consistency test, was reduced by up to 3 orders of magnitude upon heat treatment or vitrification, surpassing the performance of borosilicate glass in some cases. This was attributed to the high levels of iron and zinc in the wastes, which greatly improve the durability of phosphate glasses. One of the wastes arose from a metal phosphating process and was particularly suitable for vitrification due to its high P{sub 2}O{sub 5} content and favourable melting behaviour. The other waste, which arose from a number of processes, was less suitable as it had a low P{sub 2}O{sub 5} content and during heating it emitted harmful corrosive gases and underwent violent reactions. Substantial volume reductions were obtained by heat treatment and vitrification of both wastes. Compositions and performances of some vitrified wastes were comparable with those of glasses which are under consideration for the immobilisation of toxic and nuclear wastes.

  10. Heavy metals in municipal solid waste deposits

    Energy Technology Data Exchange (ETDEWEB)

    Flyhammar, P.

    1997-12-01

    Extensive use of heavy metals in modern society influences routes followed by fluxes on the surface of the Earth. The changed flow paths may be harmful for the balance of biological systems at different levels, micro-organisms, human beings and whole ecosystems, since the toxicity of heavy metals is determined by their concentrations and chemical forms. Despite the low mobility of heavy metals (Zn, Cu, Pb, Cr, Ni and Cd) in municipal landfills, it was found that extensive transformations of the binding forms of heavy metal take place within the waste mass during the degradation of the waste. These changes appear to be closely related to the development of early diagenetic solid phases, i.e. new secondary solid phases formed in the waste. The heavy metals often constitute a minor part of these phases and the bindings include several forms such as adsorption, complexation, coprecipitation, precipitation, etc. It was also found that the associations between heavy metals and solid phases are dominated by several binding forms to one specific substrate rather than bindings to various solid phases. The mobility of iron and manganese seems to increase during the processes involved in waste degradation due to the solution of oxide/hydroxide phases, while the heavy metals appear to become less mobile due to their binding to organic compounds and sulphides. However, one exception in this case may be nickel. Another aspect of the transformation of heavy metals is the accumulation of pools of heavy metals which can become susceptible to environmental changes, such as oxidation or acidification. However, the risk of increased mobilization caused by lower pH values seem to be limited since municipal solid waste has a large buffer capacity. 66 refs, 9 figs, 3 tabs 66 refs, 9 figs, 3 tabs

  11. Vanadium removal by metal (hydr)oxide adsorbents.

    Science.gov (United States)

    Naeem, A; Westerhoff, P; Mustafa, S

    2007-04-01

    Vanadium is listed on the United States Environment Protection Agency (USEPA) candidate contaminant list # 2 (CCL2), and regulatory guidelines for vanadium exist in some US states. The USEPA requires treatability studies before making regulatory decisions on CCL2 contaminants. Previous studies have examined vanadium adsorption onto some metal hydroxides but not onto commercially available adsorbents. This paper briefly summarizes known vanadium occurrence in North American groundwater and assesses vanadium removal by three commercially available metal oxide adsorbents with different mineralogies. GTO (Dow) is TiO2 based and E-33 (Seven Trents) and GFH (US Filter) are iron based. Preliminary vanadate adsorption kinetics onto GFH, E-33 and GTO has been studied and the homogenous surface diffusion model (HSDM) is used to describe the adsorption kinetics data. The effects of pH, vanadium concentration, and volume/mass ratio are assessed. Vanadium adsorption decreases with increasing pH, with maximum adsorption capacities achieved in at pH 3-4. Results indicate that all adsorbents remove vanadium; GFH has the highest adsorption capacity, followed by GTO and E-33. Data are best fit with the Langmuir model rather than Freundlich isotherms. Both the sorption maxima (Xm) and binding energy constant (b) follow the trend GFH>GTO>E-33. Naturally occurring vanadium is also removed from Arizona ground water in rapid small-scale column tests (RSSCTs). Metal oxide adsorption technologies currently used for arsenic removal may also remove vanadium but not always with the same effectiveness.

  12. Method of electrolytically decontaminating of radioactive metal wastes

    International Nuclear Information System (INIS)

    Oonuma, Tsutomu; Tanaka, Akio; Yamadera, Toshio.

    1985-01-01

    Purpose: To significantly reduce the volume of secondary wastes by separating from electrolytes metal ions containing radioactive metal ions dissolved therein in the form of elemental metals of a reduced volume with ease, as well as regenerating the electrolytes for re-use. Method: Contaminated portions at the surface of the radioactive metal wastes are dissolved in electrolytes and, when the metal ion concentration in the electrolytes reaches a predetermined level, the electrolytes are introduced to an acid recovery step and an electrodeposition step. The recovered acid is re-used as the electrolytes, while dissolved metal ions containing radioactive metal ions are deposited as elemental metals in the electrodeposition step. The electrolytes usable herein include those acids easily forming stable complex compounds with the metals or those not forming hydroxides of the contaminated metals. Combination of sodium sulfate and sulfuric acid, sodium chloride and hydrochloride or the like is preferred. (Kamimura, M.)

  13. Analysis of Heavy Metal in Electrocoagulated Metal Hydroxide Sludge (EMHS from the Textile Industry by Energy Dispersive X-Ray Fluorescence (EDXRF

    Directory of Open Access Journals (Sweden)

    Tanveer Mehedi Adyel

    2012-12-01

    Full Text Available Environmental pollution due to discharges of heavy metal containing sludge from textile industries is a common nuisance in Bangladesh, where no treatment of sludge is carried out before final disposals. Energy Dispersive X-ray Fluorescence (EDXRF was employed in the present study to analyze the heavy metal content of Electrocoagulated Metal Hydroxide Sludge (EMHS collected from a composite textile industry. Thirteen heavy metals, viz., Mn, Ti, Cu, Zn, Ni, Sr, V, Cr, Zr, Hg, Cd, Nb and Ga, were detected. Mn, Ni, Cu, Zn and Cd exceeded the permissible limit to apply the EMHS in agricultural land. Cr, Ni, Cu and Zn were compared to the values of the European legislation to evaluate the environmental risk and to classify the wastes as inert wastes or as wastes that have to be control landfilled. EMHS was categorized as class I and needs to be deposited in controlled landfills.

  14. Ion Recognition Approach to Volume Reduction of Alkaline Tank Waste by Separation and Recycle of Sodium Hydroxide and Sodium Nitrate

    International Nuclear Information System (INIS)

    Moyer, Bruce A.; Marchand, Alan P.; Bonnesen, Peter V.; Bryan, Jeffrey C.; Haverlock, Tamara J.

    2004-01-01

    This research was intended to provide the scientific foundation upon which the feasibility of liquid-liquid extraction chemistry for bulk reduction of the volume of high-activity tank waste can be evaluated. Primary focus has been on sodium hydroxide separation, with potential Hanford application. Value in sodium hydroxide separation can potentially be found in alternative flowsheets for treatment and disposal of low-activity salt waste. Additional value can be expected in recycle of sodium hydroxide for use in waste retrieval and sludge washing, whereupon additions of fresh sodium hydroxide to the waste can be avoided. Potential savings are large both because of the huge cost of vitrification of the low-activity waste stream and because volume reduction of high-activity wastes could obviate construction of costly new tanks. Toward these ends, the conceptual development begun in the original proposal was extended with the formulation of eight fundamental approaches that could be undertaken for extraction of sodium hydroxide

  15. Ageing behaviour of unary hydroxides in trivalent metal salt solutions

    Indian Academy of Sciences (India)

    Unknown

    Figure 2. Powder X-ray diffractogram of CuO (a) compared with those of CuO aged in aluminium nitrate for 2 days (b) and 4 days (c). Feature marked by asterisk is due to impurities. Table 2. Powder X-ray diffraction data of layered double hydroxides obtained by the ageing of unary hydroxides in Al (or Cr) salt solutions. d/Å.

  16. Thermodynamic Properties of Alkali Metal Hydroxides. Part II. Potassium, Rubidium, and Cesium Hydroxides

    International Nuclear Information System (INIS)

    Gurvich, L.V.; Bergman, G.A.; Gorokhov, L.N.; Iorish, V.S.; Leonidov, V.Y.; Yungman, V.S.

    1997-01-01

    The data on thermodynamic and molecular properties of the potassium, rubidium and cesium hydroxides have been collected, critically reviewed, analyzed, and evaluated. Tables of the thermodynamic properties [C p circ , Φ=-(G -H(0)/T, S, H -H(0), Δ f H, Δ f G)] of these hydroxides in the condensed and gaseous states have been calculated using the results of the analysis and some estimated values. The recommendations are compared with earlier evaluations given in the JANAF Thermochemical Tables and Thermodynamic Properties of Individual Substances. The properties considered are: the temperature and enthalpy of phase transitions and fusion, heat capacities, spectroscopic data, structures, bond energies, and enthalpies of formation at 298.15 K. The thermodynamic functions in solid, liquid, and gaseous states are calculated from T=0 to 2000 K for substances in condensed phase and up to 6000 K for gases. copyright 1997 American Institute of Physics and American Chemical Society

  17. Technical basis for a minimum hydroxide concentration in tanks containing dilute waste

    International Nuclear Information System (INIS)

    Zapp, P.E.

    1995-05-01

    Laboratory tests were performed to address the protection of waste tank steel from corrosion in situations of elevated temperatures up to 75 C (hot spots) in the sludge layer of Extended Sludge Processing (ESP) tanks. Coupon immersion tests were conducted at 75 C in two ESP simulants at four hydroxide (or pH) levels. The nitrite concentrations of the simulants were calculated from the ESP technical standards based on a temperature of 40 C. The results showed that a hydroxide concentration of at least 0.01 M prevented significant corrosion of the steel at the elevated temperature. This conclusion provides the technical basis for the revised minimum hydroxide concentration of 0.01 M in the draft WSRC 241-82H Control Room Process Requirements, for the ESP tanks

  18. Surface Properties of Metal Hydroxide Microparticles in the Ambient Air

    Directory of Open Access Journals (Sweden)

    Zakharenko Valery

    2017-01-01

    Full Text Available The adsorption and photoadsorption properties of Mg(OH2 and Ca(OH2 microparticles in the ambient air were investigated. The compositional analysis of an adsorption layer of microparticles was carried out. The kinetics of photodesorption of molecules from microcrystal surfaces and the interaction of HCFC-22 (CHF2Cl in the dark and under light were studied. Quantum yields and their spectral dependencies were determined for CO2 photodesorption, O2 and CO photoadsorption. The effect of weakly bound CO displacement from the surface of microparticles was revealed during dark adsorption of HCFC-22. It is supposed that adsorbed CO is formed as a result of atmospheric CO2 reduction after the break of Mg—OH bonds. In case of calcium hydroxide, CO is generated during the interaction of calcium hydroxide with carbon dioxide in the presence of water.

  19. Volumetric determination of hydroxide, aluminate, and carbonate in alkaline solutions of nuclear waste

    International Nuclear Information System (INIS)

    Baumann, E.W.

    1975-06-01

    An integrated procedure was developed for determining OH - , Al(OH) 4 - , and CO 3 2- in alkaline nuclear waste. The free alkali, the hydroxide released when Al(OH) 3 is complexed with oxalate, and the precipitated BaCO 3 were determined by acidimetric titration. With a 50-μl sample, the relative standard deviations were 1 to 2 percent for nonradioactive test solutions and 2 to 5 percent for radioactive process solutions. (U.S.)

  20. Nuclear waste storage container with metal matrix

    Science.gov (United States)

    Sump, Kenneth R.

    1978-01-01

    The invention relates to a storage container for high-level waste having a metal matrix for the high-level waste, thereby providing greater impact strength for the waste container and increasing heat transfer properties.

  1. Nuclear waste storage container with metal matrix

    International Nuclear Information System (INIS)

    Sump, K.R.

    1978-01-01

    The invention relates to a storage container for high-level waste having a metal matrix for the high-level waste, thereby providing greater impact strength for the waste container and increasing heat transfer properties

  2. Retention of heavy metals on layered double hydroxides thin films deposited by pulsed laser deposition

    Energy Technology Data Exchange (ETDEWEB)

    Vlad, A., E-mail: angela.vlad@gmail.com [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Str., 76900 Bucharest-Magurele (Romania); Birjega, R.; Matei, A.; Luculescu, C.; Mitu, B.; Dinescu, M. [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Str., 76900 Bucharest-Magurele (Romania); Zavoianu, R.; Pavel, O.D. [University of Bucharest, Faculty of Chemistry, Department of Chemical Technology and Catalysis, 4-12 Regina Elisabeta Bd., Bucharest (Romania)

    2014-05-01

    Heavy metals are toxic and hazardous pollutants in the environment due to their nonbiodegradability and persistence, which can pose serious threats to living organisms. The ability of Mg–Al based layered double hydroxides (LDHs) thin films to retain heavy metals from aqueous solutions at different concentrations is a novel topic with prospects of attractive applications, such as detection of heavy metals. We report on the ability of a series of Mg–Al based layered double hydroxides thin films to detect Ni and Co cations in aqueous solutions. Uptake of heavy metals ions such as Ni{sup 2+}, Co{sup 2+} from aqueous solutions was studied as function of contact time at a standard metal ion concentration. The LDHs thin films were deposited using pulsed laser deposition (PLD). The different adsorption mechanisms were studied in connection with different heavy metals used as probe cations. X-ray diffraction, atomic force microscopy, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, Fourier transform infra-red spectroscopy were the techniques used for the investigation of as deposited and after heavy metals retention thin films.

  3. Structural Differentiation between Layered Single (Ni) and Double Metal Hydroxides (Ni–Al LDHs) Using Wavelet Transformation

    Energy Technology Data Exchange (ETDEWEB)

    Siebecker, Matthew G. [University of Delaware, Delaware Environmental Institute; Sparks, Donald L. [University of Delaware, Delaware Environmental Institute

    2017-09-07

    Layered double hydroxides (LDHs) are anionic clays important in disciplines such as environmental chemistry, geochemistry, and materials science. Developments in signal processing of extended X-ray absorption fine structure (EXAFS) data, such as wavelet transformation (WT), have been used to identify transition metals and Al present in the hydroxide sheets of LDHs. The WT plots of LDHs should be distinct from those of isostructural single metal hydroxides. However, no direct comparison of these minerals appears in the literature using WT. This work systematically analyzes a suite of Ni-rich mineral standards, including Ni–Al LDHs, single metal Ni hydroxides, and Ni-rich silicates using WT. The results illustrate that the WT plots for α-Ni(OH)2 and Ni–Al LDHs are often indistinguishable from each other, with similar two-component plots for the different mineral types. This demonstrates that the WT of the first metal shell often cannot be used to differentiate an LDH from a single metal hydroxide. Interlayer anions adsorbed to the hydroxide sheet of α-Ni(OH)2 affect the EXAFS spectra and are not visible in the FT but are clearly resolved and discrete in the WT.

  4. Melting of contaminated metallic waste

    International Nuclear Information System (INIS)

    Lee, Y.-S.; Cheng, S.-Y.; Kung, H.-T.; Lin, L.-F.

    2004-01-01

    Approximately 100 tons of contaminated metallic wastes were produced each year due to maintenance for each TPC's nuclear power reactor and it was roughly estimated that there will be 10,000 tons of metallic scraps resulted from decommissioning of each reactor in the future. One means of handling the contaminated metal is to melt it. Melting process owns not only volume reduction which saves the high cost of final disposal but also resource conservation and recycling benefits. Melting contaminated copper and aluminum scraps in the laboratory scale have been conducted at INER. A total of 546 kg copper condenser tubes with a specific activity of about 2.7 Bq/g was melted in a vacuum induction melting facility. Three types of products, ingot, slag and dust were derived from the melting process, with average activities of 0.10 Bq/g, 2.33 Bq/g and 84.3 Bq/g respectively. After the laboratory melting stage, a pilot plant with a 500 kg induction furnace is being designed to melt the increasingly produced contaminated metallic scraps from nuclear facilities and to investigate the behavior of different radionuclides during melting. (author)

  5. Studies on MgNi-Based Metal Hydride Electrode with Aqueous Electrolytes Composed of Various Hydroxides

    Directory of Open Access Journals (Sweden)

    Jean Nei

    2016-08-01

    Full Text Available Compositions of MgNi-based amorphous-monocrystalline thin films produced by radio frequency (RF sputtering with a varying composition target have been optimized. The composition Mg52Ni39Co3Mn6 is identified to possess the highest initial discharge capacity of 640 mAh·g−1 with a 50 mA·g−1 discharge current density. Reproduction in bulk form of Mg52Ni39Co3Mn6 alloy composition was prepared through a combination of melt spinning (MS and mechanical alloying (MA, shows a sponge-like microstructure with >95% amorphous content, and is chosen as the metal hydride (MH alloy for a sequence of electrolyte experiments with various hydroxides including LiOH, NaOH, KOH, RbOH, CsOH, and (C2H54N(OH. The electrolyte conductivity is found to be closely related to cation size in the hydroxide compound used as 1 M additive to the 4 M KOH aqueous solution. The degradation performance of Mg52Ni39Co3Mn6 alloy through cycling demonstrates a strong correlation with the redox potential of the cation in the alkali hydroxide compound used as 1 M additive to the 5 M KOH aqueous solution. NaOH, CsOH, and (C2H54N(OH additions are found to achieve a good balance between corrosion and conductivity performances.

  6. Synthesis of graphene oxide-intercalated alpha-hydroxides by metathesis and their decomposition to graphene/metal oxide composites

    OpenAIRE

    Nethravathi, C; Rajamathi, Michael; Ravishankar, N; Basit, Lubna; Felser, Claudia

    2010-01-01

    Graphene oxide-intercalated alpha-metal hydroxides were prepared using layers from the delaminated colloidal dispersions of cetyltrimethylammonium-intercalated graphene oxide and dodecylsulfate-intercalated alpha-hydroxide of nickel/cobalt as precursors. The reaction of the two dispersions leads to de-intercalation of the interlayer ions from both the layered solids and the intercalation of the negatively charged graphene oxide sheets between the positively charged layers of the alpha-hydroxi...

  7. Enrichment of rare earth metal ions by the highly selective adsorption of phytate intercalated layered double hydroxide.

    Science.gov (United States)

    Jin, Cheng; Liu, Huimin; Kong, Xianggui; Yan, Hong; Lei, Xiaodong

    2018-02-27

    Phytate intercalated MgAl layered double hydroxide (MgAl-LDH) was prepared by an anion exchange method with the precursor NO 3 - containing MgAl-LDH. The final as-synthesized product [Mg 0.69 Al 0.31 (OH) 2 ] (phytateNa 6 ) 0.05 (NO 3 ) 0.01 ·mH 2 O (phytate-LDH) has highly selective adsorption ability for some metal ions and can be used to enrich rare earth metal ions in mixed solution, such as Pr 3+ and Ce 3+ from a mixed solution of them with Pb 2+ and Co 2+ . At first, phytate-LDH has good adsorption performance for these ions in single metal ion solutions. At low concentration (below 10 mg L -1 ), all the capture rates of the four metal ions were more than 97%, for highly toxic Pb 2+ it was even up to nearly 100%, and a high capture rate (99.87%) was maintained for Pb 2+ at a high concentration (100 mg L -1 ). When all the four metal ions are co-existing in aqueous solution, the selectivity order is Pb 2+ ≫ Pr 3+ ≈ Ce 3+ > Co 2+ . In a solution containing mixtures of the three metal ions of Pr 3+ , Ce 3+ , and Co 2+ , the selectivity order is Pr 3+ ≈ Ce 3+ ≫ Co 2+ , and in a solution containing mixtures of Pr 3+ with Co 2+ and Ce 3+ with Co 2+ , the selectivity orders are Pr 3+ ≫ Co 2+ and Ce 3+ ≫ Co 2+ , respectively. The high selectivity and adsorption capacities for Pb 2+ , Co 2+ , Pr 3+ , and Ce 3+ result in the efficient removal of Pb 2+ and enrichment of the rare earth metal ions Pr 3+ and Ce 3+ by phytate-LDH. Based on the elemental analysis, it is found that the difference of the adsorption capacities is mainly due to the different coordination number of them with phytate-LDH. With molecular simulation, we believe that the adsorption selectivity is due to the difference of the binding energy between the metal ion and phytate-LDH. Therefore, the phytate-LDH is promising for the enrichment and/or purification of the rare earth metal ions and removal of toxic metal ions from waste water.

  8. Perspective of metal encapsulation of waste

    International Nuclear Information System (INIS)

    Jardine, L.J.; Steindler, M.J.

    1978-01-01

    A conceptual flow sheet is presented for encapsulating solid, stabilized calcine (e.g., supercalcine) in a solid lead alloy, using existing or developing technologies. Unresolved and potential problem areas of the flow sheet are outlined and suggestions are made as how metal encapsulation might be applied to other solid wastes from the fuel cycle. It is concluded that metal encapsulation is a technique applicable to many forms of solid wastes and is likely to meet future waste isolation criteria and regulations

  9. Coprecipitation with metal hydroxides for the determination of beryllium in seawater by graphite furnace atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Hiraide, M.; Ishikawa, K.; Chen, Z.S.; Kawaguchi, H.

    1994-01-01

    Coprecipitation first with magnesium hydroxide. next with tin(IV) hydroxide is developed for the determination of traces of beryllium in seawater. To a 200-ml sample is added a sodium hydroxide solution to form magnesium hydroxide at pH 11.5, on which beryllium is quantitatively coprecipitated. The precipitate is separated by centrifugation and dissolved in 2 ml of 12 mol/l hydrochloric acid. The resulting solution (ca. 10 ml) is mixed with 2 mg of tin(IV) carrier and the pH is adjusted to 5.0 to collect the beryllium on tin(IV) hydroxide, leaving magnesium ions in the solution. The tin(IV) hydroxide is centrifuged, dissolved in 0.1 ml of 5 mol/l hydrobromic acid, and then diluted to 1 ml with water. Magnesium is so added as to be 500 μg/ml for increasing the sensitivity about four times, and the beryllium in the solution is determined by graphite furnace atomic absorption spectrometry. The experiments with synthetic seawater samples showed that pg-μg amounts of beryllium can be coprecipitated on the metal hydroxides and beryllium at the low ng/l level can be determined with reasonable precision (RSD < 10%). The detection limit of the proposed method is 0.5 ng/l of beryllium in seawater. (author)

  10. Influence of alkali metal hydroxides on corrosion of Zr-based alloys

    International Nuclear Information System (INIS)

    Jeong, Y.H.; Ruhmann, H.; Garzarolli, F.

    1997-01-01

    In this study the influence of group-1 alkali hydroxides on different zirconium based alloys has been evaluated. The experiments have been carried out in small stainless steel autoclaves at 350 deg. C in pressurized 17 MPa water, with in low (0.32 mmol), medium (4.3 mmol) and high (31.5 mmol) equimolar concentrations of Li-, Na-, K-, Rb- and Cs-Hydroxides. Two types of alloys have been investigated: Zr-Sn-(Transition metal) and Zr-Sn-Nb-(Transition metal). The corrosion behaviour was evaluated from weight gain measurements. From the experiments the cation could be identified as the responsible species for zirconium alloy corrosion in alkalized water. The radius of the cation governs the corrosion behaviour in the pre accelerated region of zircaloy corrosion. Incorporating of alkali cations into the zirconium oxide lattice is probably the mechanism which allows the corrosion enhancement for Li and Na and the significantly lower effect for the other bases. Nb containing alloys show lower corrosion resistance than alloys from the Zr-Sn-TRM system in all alkali solutions. Both types of alloys corrode significantly more in LiOH and NaOH than in the other alkali environments. Lowest corrosive aggressiveness has been found for CsOH followed by KOH. Concluding from the corrosion behaviour in the different alkali environments and taking into account the tendency to promote accelerate corrosion, CsOH and KOH are possible alternate alkalis for PWR application. (author). 17 refs, 15 figs, 5 tabs

  11. Influence of alkali metal hydroxides on corrosion of Zr-base alloys

    International Nuclear Information System (INIS)

    Jeong, Yong Hwan

    1996-01-01

    The influence of group-1 alkali hydroxides on different Zr-based alloys have been carried out in static autoclaves at 350 deg C in pressurized water, conditioned in low(0.32 mmol), medium(4.3 mmol) and high(31.5 mmol) equimolar concentration of Li-, Na-, K-, Rb- and Cs-hydroxide. Two types of alloys have been investigated: Zr-Sn-(TRM, Transition metal) and Zr-Sn-Nb-(TRM, Transition metal). From the experiments the cation could be identified as the responsible species for corrosion of Zr alloy in alkalized water. The radius of the cation governs the accelerated corrosion in the pre-transition region of Zr alloy. Incorporation of alkali cation into the zirconium oxide lattice is probably the mechanism which allows the corrosion enhancement for Li and Na and the significant lower effect for the other bases. Nb containing alloys showed lower corrosion resistance than Zr-Sn-TRM alloys in all alkali solutions. Both types of alloys were corroded significantly more in LiOH and NaOH than in the other alkali environments. Lowest corrosive aggressiveness has been found for CsOH followed by KOH. Concluding from the corrosion behavior in the different alkali environments and taking into account the tendency to accelerate the corrosion of Zr alloys, CsOH and KOH are possible alternate alkali for PWR (Pressurized Water Reactor) application. (author)

  12. Heavy metal ion removal by thiol functionalized aluminum oxide hydroxide nanowhiskers

    Science.gov (United States)

    Xia, Zhiyong; Baird, Lance; Zimmerman, Natasha; Yeager, Matthew

    2017-09-01

    In this study, we developed a cost effective method of using thiol functionalized γ-aluminum oxide hydroxide (γ-AlOOH) filters for removing three key heavy metals from water: mercury, lead, and cadmium under non-concomitant conditions. Compared to non-thiol treated γ-AlOOH filters, the introduction of thiol functional groups greatly improved the heavy metal removal efficiency under both static and dynamic filtration conditions. The adsorption kinetics of thiol functionalized γ-AlOOH were investigated using the Lagergren first order and pseudo-second order kinetics models; whereas the isothermal adsorption behavior of these membranes was revealed through the Langmuir and Freundlich models. Heavy metal concentration was quantified by Inductively Coupled Plasma-Mass Spectroscopy, and the thiol level on γ-AlOOH surface was measured by a colorimetric assay using Ellman's reagent. X-ray photoelectron spectroscopy was used to further address the surface sulfur state on the membranes after heavy metal exposure. Mechanisms for heavy metal adsorption were also discussed.

  13. Anion-intercalated layered double hydroxides modified test strips for detection of heavy metal ions.

    Science.gov (United States)

    Wang, Nan; Sun, Jianchao; Fan, Hai; Ai, Shiyun

    2016-01-01

    In this work, a novel approach for facile and rapid detection of heavy metal ions using anion-intercalated layered double hydroxides (LDHs) modified test strips is demonstrated. By intercalating Fe(CN)6(4-) or S(2-) anions into the interlayers of LDHs on the filter paper, various heavy metal ions can be easily detected based on the color change before and after reaction between the anions and the heavy metal ions. Upon the dropping of heavy metal ions solutions to the test strips, the colors of the test strips changed instantly, which can be easily observed by naked eyes. With the decrease of the concentration, the color depth changed obviously. The lowest detection concentration can be up to 1×10(-6) mol L(-1). Due to the easily intercalation of anions into the interlayer of the LDHs on test trips, this procedure provides a general method for the construction of LDHs modified test strips for detection of heavy metal ions. The stability of the prepared test strips is investigated. Furthermore, all the results were highly reproducible. The test strips may have potential applications in environmental monitoring fields. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Cobalt Iron Hydroxide as a Precious Metal-Free Bifunctional Electrocatalyst for Efficient Overall Water Splitting.

    Science.gov (United States)

    Babar, Pravin; Lokhande, Abhishek; Shin, Hyeong Ho; Pawar, Bharati; Gang, Myeng Gil; Pawar, Sambhaji; Kim, Jin Hyeok

    2018-02-01

    Highly efficient and stable electrocatalysts from inexpensive and earth-abundant elements are emerging materials in the overall water splitting process. Herein, cobalt iron hydroxide nanosheets are directly deposited on nickel foam by a simple and rapid electrodeposition method. The cobalt iron hydroxide (CoFe/NF) nanosheets not only allow good exposure of the highly active surface area but also facilitate the mass and charge transport capability. As an anode, the CoFe/NF electrocatalyst displays excellent oxygen evolution reaction catalytic activity with an overpotential of 220 mV at a current density of 10 mA cm -2 . As a cathode, it exhibits good performance in the hydrogen evolution reaction with an overpotential of 110 mV, reaching a current density of 10 mA cm -2 . When CoFe/NF electrodes are used as the anode and the cathode for water splitting, a low cell voltage of 1.64 V at 10 mA cm -2 and excellent stability for 50 h are observed. The present work demonstrates a possible pathway to develop a highly active and durable substitute for noble metal electrocatalysts for overall water splitting. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Selectivity of layered double hydroxides and their derivative mixed metal oxides as sorbents of hydrogen sulfide.

    Science.gov (United States)

    Othman, Mohamed A; Zahid, Waleed M; Abasaeed, Ahmed E

    2013-06-15

    In the context of finding high efficient sorbent materials for removing hydrogen sulfide (H2S) from air stream, a screening study was performed to find the best combination of metals for the synthesis of layered double hydroxides (LDHs) and their derivative mixed metal oxides. Based on selectivity of 998 natural mineral species of sulfur-containing compounds, Cu(2+), Ni(2+) and Zn(2+) were selected as divalent metals, and Fe(3+), Al(3+) and Cr(3+) as trivalent metals to synthesis the LDHs sorbents. 10 LDHs materials and their calcined mixed metal oxides, Ni(0.66)Al(0.34), Cu(0.35)Ni(0.32)Al(0.33), Zn(0.66)Al(0.34), Cu(0.36)Zn(0.32)Al(0.32), Ni(0.64)Fe(0.36), Cu(0.35)Ni(0.31)Fe(0.34), Ni(0.66)Cr(0.34), Cu(0.35)Ni(0.31)Cr(0.34), Zn(0.66)Cr(0.34), Cu(0.33)Zn(0.32)Cr(0.35) were synthesized, characterized chemically and physically, and then tested using breakthrough test to determine their sulfur uptake. Ni(0.64)Fe(0.36) mixed metal oxides was found to have the best uptake of hydrogen sulfide (136 mg H₂S/g). Regeneration of spent Ni(0.64)Fe(0.36) mixed metal oxides was studied using two different mixture solutions, NaCl/NaOH and acetate-buffer/NaCl/NaOH. The latter mixture successfully desorbed the sulfur from the Ni0.64Fe0.36 sorbent for 2 cycles of regeneration/sorption. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Influence of pH on the redox chemistry of metal (hydr)oxides and organic matter in paddy soils

    NARCIS (Netherlands)

    Pan, Y.; Koopmans, G.F.; Bonten, L.T.C.; Song, J.; Luo, Y.; Temminghoff, E.J.M.; Comans, R.N.J.

    2014-01-01

    The primary purpose of this study was to determine how flooding and draining cycles affect the redox chemistry of metal (hydr)oxides and organic matter in paddy soils and how the pH influences these processes. Our secondary purpose was to determine to what extent a geochemical thermodynamic

  17. Oxidatively Electrodeposited Thin-Film Transition Metal (Oxy)hydroxides as Oxygen Evolution Catalysts.

    Science.gov (United States)

    Morales-Guio, Carlos G; Liardet, Laurent; Hu, Xile

    2016-07-20

    The electrolysis of water to produce hydrogen and oxygen is a simple and attractive approach to store renewable energies in the form of chemical fuels. The oxygen evolution reaction (OER) is a complex four-electron process that constitutes the most energy-inefficient step in water electrolysis. Here we describe a novel electrochemical method for the deposition of a family of thin-film transition metal (oxy)hydroxides as OER catalysts. The thin films have nanodomains of crystallinity with lattice spacing similar to those of double-layered hydroxides. The loadings of these thin-film catalysts were accurately determined with a resolution of below 1 μg cm(-2) using an electrochemical quartz microcrystal balance. The loading-activity relations for various catalysts were established using voltammetry and impedance spectroscopy. The thin-film catalysts have up to four types of loading-activity dependence due to film nucleation and growth as well as the resistance of the films. A zone of intrinsic activity has been identified for all of the catalysts where the mass-averaged activity remains constant while the loading is increased. According to their intrinsic activities, the metal oxides can be classified into three categories: NiOx, MnOx, and FeOx belong to category I, which is the least active; CoOx and CoNiOx belong to category II, which has medium activity; and FeNiOx, CoFeOx, and CoFeNiOx belong to category III, which is the most active. The high turnover frequencies of CoFeOx and CoFeNiOx at low overpotentials and the simple deposition method allow the fabrication of high-performance anode electrodes coated with these catalysts. In 1 M KOH and with the most active electrode, overpotentials as low as 240 and 270 mV are required to reach 10 and 100 mA cm(-2), respectively.

  18. Nuclear fuel cycle waste recycling technology deverlopment - Radioactive metal waste recycling technology development

    International Nuclear Information System (INIS)

    Oh, Won Zin; Moon, Jei Kwon; Jung, Chong Hun; Park, Sang Yoon

    1998-08-01

    With relation to recycling of the radioactive metal wastes which are generated during operation and decommissioning of nuclear facilities, the following were described in this report. 1. Analysis of the state of the art on the radioactive metal waste recycling technologies. 2. Economical assessment on the radioactive metal waste recycling. 3. Process development for radioactive metal waste recycling, A. Decontamination technologies for radioactive metal waste recycling. B. Decontamination waste treatment technologies, C. Residual radioactivity evaluation technologies. (author). 238 refs., 60 tabs., 79 figs

  19. Magnesium alloys and graphite wastes encapsulated in cementitious materials: Reduction of galvanic corrosion using alkali hydroxide activated blast furnace slag

    International Nuclear Information System (INIS)

    Chartier, D.; Muzeau, B.; Stefan, L.; Sanchez-Canet, J.; Monguillon, C.

    2017-01-01

    Highlights: • Embedded in cement, magnesium is corroded by residual water present in porosity of the matrix. • Corrosion is enhanced by galvanic phenomenon when magnesium is in contact with graphite. • Galvanic corrosion of magnesium in contact with graphite debris is shown to be severe with ordinary Portland cement. • Galvanic corrosion is significantly lowered in high alkali medium such as sodium hydroxide. • Sodium hydroxide activated blast furnace slag is a convenient binder to embed magnesium. - Abstract: Magnesium alloys and graphite from spent nuclear fuel have been stored together in La Hague plant. The packaging of these wastes is under consideration. These wastes could be mixed in a grout composed of industrially available cement (Portland, calcium aluminate…). Within the alkaline pore solution of these matrixes, magnesium alloys are imperfectly protected by a layer of Brucite resulting in a slow corrosion releasing hydrogen. As the production of this gas must be considered for the storage safety, and the quality of wasteform, it is important to select a cement matrix capable of lowering the corrosion kinetics. Many types of calcium based cements have been tested and most of them have caused strong hydrogen production when magnesium alloys and graphite are conditioned together because of galvanic corrosion. Exceptions are binders based on alkali hydroxide activated ground granulated blast furnace slag (BFS) which are presented in this article.

  20. Magnesium alloys and graphite wastes encapsulated in cementitious materials: Reduction of galvanic corrosion using alkali hydroxide activated blast furnace slag

    Energy Technology Data Exchange (ETDEWEB)

    Chartier, D., E-mail: david.chartier@cea.fr [Commissariat à l' Energie Atomique et aux Energies Alternatives, CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze (France); Muzeau, B. [DEN-Service d’Etude du Comportement des Radionucléides (SECR), CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette (France); Stefan, L. [AREVA NC/D& S - France/Technical Department, 1 place Jean Millier 92084 Paris La Défense (France); Sanchez-Canet, J. [Commissariat à l' Energie Atomique et aux Energies Alternatives, CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze (France); Monguillon, C. [DEN-Service d’Etude du Comportement des Radionucléides (SECR), CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette (France)

    2017-03-15

    Highlights: • Embedded in cement, magnesium is corroded by residual water present in porosity of the matrix. • Corrosion is enhanced by galvanic phenomenon when magnesium is in contact with graphite. • Galvanic corrosion of magnesium in contact with graphite debris is shown to be severe with ordinary Portland cement. • Galvanic corrosion is significantly lowered in high alkali medium such as sodium hydroxide. • Sodium hydroxide activated blast furnace slag is a convenient binder to embed magnesium. - Abstract: Magnesium alloys and graphite from spent nuclear fuel have been stored together in La Hague plant. The packaging of these wastes is under consideration. These wastes could be mixed in a grout composed of industrially available cement (Portland, calcium aluminate…). Within the alkaline pore solution of these matrixes, magnesium alloys are imperfectly protected by a layer of Brucite resulting in a slow corrosion releasing hydrogen. As the production of this gas must be considered for the storage safety, and the quality of wasteform, it is important to select a cement matrix capable of lowering the corrosion kinetics. Many types of calcium based cements have been tested and most of them have caused strong hydrogen production when magnesium alloys and graphite are conditioned together because of galvanic corrosion. Exceptions are binders based on alkali hydroxide activated ground granulated blast furnace slag (BFS) which are presented in this article.

  1. Application of magnesium hydroxide and barium hydroxide for the ...

    African Journals Online (AJOL)

    Application of magnesium hydroxide and barium hydroxide for the removal of metals and sulphate from mine water. ... equivalent to the Ba(OH)2 dosage. During CO2-dosing, CaCO3 is precipitated to the saturation level of CaCO3. Keywords: Magnesium hydroxide; barium hydroxide; sulphate removal; water treatment ...

  2. Manipulating the Architecture of Atomically Thin Transition Metal (Hydr)oxides for Enhanced Oxygen Evolution Catalysis.

    Science.gov (United States)

    Dou, Yuhai; Zhang, Lei; Xu, Jiantie; He, Chun-Ting; Xu, Xun; Sun, Ziqi; Liao, Ting; Nagy, Balázs; Liu, Porun; Dou, Shi Xue

    2018-02-27

    Graphene-like nanomaterials have received tremendous research interest due to their atomic thickness and fascinating properties. Previous studies mainly focus on the modulation of their electronic structures, which undoubtedly optimizes the electronic properties, but is not the only determinant of performance in practical applications. Herein, we propose a generalized strategy to incrementally manipulate the architectures of several atomically thin transition metal (hydr)oxides, and study their effects on catalytic water oxidation. The results demonstrate the obvious superiority of a wrinkled nanosheet architecture in both catalytic activity and durability. For instance, wrinkled Ni(OH) 2 nanosheets display a low overpotential of 358.2 mV at 10 mA cm -2 , a high current density of 187.2 mA cm -2 at 500 mV, a small Tafel slope of 54.4 mV dec -1 , and excellent long-term durability with gradually optimized performance, significantly outperforming other nanosheet architectures and previously reported catalysts. The outstanding catalytic performance is mainly attributable to the 3D porous network structure constructed by wrinkled nanosheets, which not only provides sufficient contact between electrode materials and current collector, but also offers highly accessible channels for facile electrolyte diffusion and efficient O 2 escape. Our study provides a perspective on improving the performance of graphene-like nanomaterials in a wide range of practical applications.

  3. Mesoporous mixed metal oxides derived from P123-templated Mg-Al layered double hydroxides

    International Nuclear Information System (INIS)

    Wang Jun; Zhou Jideng; Li Zhanshuang; He Yang; Lin Shuangshuang; Liu Qi; Zhang Milin; Jiang Zhaohua

    2010-01-01

    We report the preparation of mesoporous mixed metal oxides (MMOs) through a soft template method. Different amounts of P123 were used as structure directing agent to synthesize P123-templated Mg-Al layered double hydroxides (LDHs). After calcination of as-synthesized LDHs at 500 o C, the ordered mesopores were obtained by removal of P123. The mesoporous Mg-Al MMOs fabricated by using 2 wt% P123 exhibited a high specific surface area of 108.1 m 2 /g, and wide distribution of pore size (2-18 nm). An investigation of the 'memory effect' of the mesoporous MMOs revealed that they were successfully reconstructed to ibuprofen intercalated LDHs having different gallery heights, which indicated different intercalation capacities. Due to their mesoporosity these unique MMOs have particular potential as drug or catalyst carriers. - Graphical abstract: Ordered mesoporous Mg-Al MMOs can be obtained through the calcination of P123-templated Mg-Al-CO 3 LDHs. The pore diameter is 2.2 nm. At the presence of ibuprofen, the Mg-Al MMOs can recover to Mg-Al-IBU LDHs, based on its 'remember effect'. Display Omitted

  4. Immobilization with Metal Hydroxides as a Means To Concentrate Food-Borne Bacteria for Detection by Cultural and Molecular Methods†

    OpenAIRE

    Lucore, Lisa A.; Cullison, Mark A.; Jaykus, Lee-Ann

    2000-01-01

    The application of nucleic acid amplification methods to the detection of food-borne pathogens could be facilitated by concentrating the organisms from the food matrix before detection. This study evaluated the utility of metal hydroxide immobilization for the concentration of bacterial cells from dairy foods prior to detection by cultural and molecular methods. Using reconstituted nonfat dry milk (NFDM) as a model, two food-borne pathogens (Listeria monocytogenes and Salmonella enterica sero...

  5. Aluminum Hydroxide and Magnesium Hydroxide

    Science.gov (United States)

    Aluminum Hydroxide, Magnesium Hydroxide are antacids used together to relieve heartburn, acid indigestion, and upset stomach. They ... They combine with stomach acid and neutralize it. Aluminum Hydroxide, Magnesium Hydroxide are available without a prescription. ...

  6. Microbial leaching of waste solder for recovery of metal.

    Science.gov (United States)

    Hocheng, H; Hong, T; Jadhav, U

    2014-05-01

    This study proposes an environment-friendly bioleaching process for recovery of metals from solders. Tin-copper (Sn-Cu), tin-copper-silver (Sn-Cu-Ag), and tin-lead (Sn-Pb) solders were used in the current study. The culture supernatant of Aspergillus niger removed metals faster than the culture supernatant of Acidithiobacillus ferrooxidans. Also, the metal removal by A. niger culture supernatant is faster for Sn-Cu-Ag solder as compared to other solder types. The effect of various process parameters such as shaking speed, temperature, volume of culture supernatant, and increased solder weight on bioleaching of metals was studied. About 99 (±1.75) % metal dissolution was achieved in 60 h, at 200-rpm shaking speed, 30 °C temperature, and by using 100-ml A. niger culture supernatant. An optimum solder weight for bioleaching was found to be 5 g/l. Addition of sodium hydroxide (NaOH) and sodium chloride (NaCl) in the bioleached solution from Sn-Cu-Ag precipitated tin (85 ± 0.35 %) and silver (80 ± 0.08 %), respectively. Passing of hydrogen sulfide (H2S) gas at pH 8.1 selectively precipitated lead (57.18 ± 0.13 %) from the Sn-Pb bioleached solution. The proposed innovative bioleaching process provides an alternative technology for recycling waste solders to conserve resources and protect environment.

  7. The effect of metal (hydr)oxide nano-enabling on intraparticle mass transport of organic contaminants in hybrid granular activated carbon.

    Science.gov (United States)

    Garcia, Jose; Markovski, Jasmina; McKay Gifford, J; Apul, Onur; Hristovski, Kiril D

    2017-05-15

    The overarching goal of this study was to ascertain the changes in intraparticle mass transport rates for organic contaminants resulting from nano-enabled hybridization of commercially available granular activated carbon (GAC). Three different nano-enabled hybrid media were fabricated by in-situ synthesizing titanium dioxide nanoparticles inside the pores of GAC sorbent, characterized, and evaluated for removal of two model organic contaminants under realistic conditions to obtain the intraparticle mass transport (pore and surface diffusion) coefficients. The results validated the two hypotheses that: (H1) the pore diffusion rates of organic contaminants linearly decrease with decrease in cumulative pore volume caused by increase in metal (hydr)oxide nanoparticle content inside the pores of the hybrid GAC sorbent; and (H2) introduction of metal (hydr)oxide nanoparticles initially increases surface diffusivity, but additional loading causes its decrease as the increase in metal (hydr)oxide nanoparticles content continues to reduce the porosity of the GAC sorbent. Nano-enabled hybridization of commercially available GAC with metal (hydr)oxides has the potential to significantly increase the intraparticle mass transport limitations for organic contaminants. Introduction of metal (hydr)oxide nanoparticles inside the pores of a pristine sorbent causes the pore diffusion rates of organic contaminants to decrease as the cumulative pore volume is reduced. In contrast, the introduction of limited amounts of metal (hydr)oxide nanoparticles appears to facilitate the surface diffusion rates of these contaminants. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Electrochemical behaviour of metal hexacyanoferrate converted to metal hydroxide films immobilized on indium tin oxide electrodes-Catalytic ability towards alcohol oxidation in alkaline medium

    International Nuclear Information System (INIS)

    Ganesh, V.; Latha Maheswari, D.; Berchmans, Sheela

    2011-01-01

    Graphical abstract: - Abstract: In this work, we demonstrate a simple method to modify indium tin oxide (ITO) electrodes in order to perform electro-catalytic oxidation of alcohols in alkaline medium. Metal hexacyanoferrate (MHCF) films such as nickel hexacyanoferrate (NiHCF) and copper hexacyanoferrate (CuHCF) were successfully immobilized on ITO electrodes using an electrochemical method. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were employed to characterize the structural and morphological aspects of MHCF films. Cyclic voltammetry (CV) was used to study the redox properties and to determine the surface coverage of these films on ITO electrodes. Electrochemical potential cycling was carried out in alkaline medium in order to alter the chemical structure of these films and convert to their corresponding metal hydroxide films. SEM and XPS were performed to analyze the structure and morphology of metal hydroxide modified electrodes. Electro-catalytic oxidation ability of these films towards methanol and ethanol in alkaline medium was investigated using CV. From these studies we found that metal hydroxide modified electrodes show a better catalytic performance and good stability for methanol oxidation along with the alleviation of CO poisoning effect. We have obtained an anodic oxidation current density of ∼82 mA cm -2 for methanol oxidation, which is at least 10 fold higher than that of any metal hydroxide modified electrodes reported till date. The onset potential for methanol oxidation is lowered by ∼200 mV compared to other chemically modified electrodes reported. A plausible mechanism was proposed for the alcohol oxidation based on the redox properties of these modified electrodes. The methodology adapted in this work does not contain costlier noble metals like platinum and ruthenium and is economically viable.

  9. Technology Readiness Evaluation For Aluminum Removal And Sodium Hydroxide Regenration From Hanford Tank Waste By Lithium Hydrotalcite Precipitation

    International Nuclear Information System (INIS)

    Sams, T.L.; Massie, H.L.

    2011-01-01

    A Technology Readiness Evaluation (TRE) performed by AREV A Federal Services, LLC (AFS) for Washington River Protection Solutions, LLC (WRPS) shows the lithium hydrotalcite (LiHT) process invented and patented (pending) by AFS has reached an overall Technology Readiness Level (TRL) of 3. The LiHT process removes aluminum and regenerates sodium hydroxide. The evaluation used test results obtained with a 2-L laboratory-scale system to validate the process and its critical technology elements (CTEs) on Hanford tank waste simulants. The testing included detailed definition and evaluation for parameters of interest and validation by comparison to analytical predictions and data quality objectives for critical subsystems. The results of the TRE would support the development of strategies to further mature the design and implementation of the LiHT process as a supplemental pretreatment option for Hanford tank waste.

  10. Iron phosphate compositions for containment of hazardous metal waste

    Science.gov (United States)

    Day, D.E.

    1998-05-12

    An improved iron phosphate waste form for the vitrification, containment and long-term disposition of hazardous metal waste such as radioactive nuclear waste is provided. The waste form comprises a rigid iron phosphate matrix resulting from the cooling of a melt formed by heating a batch mixture comprising the metal waste and a matrix-forming component. The waste form comprises from about 30 to about 70 weight percent P{sub 2}O{sub 5} and from about 25 to about 50 weight percent iron oxide and has metals present in the metal waste chemically dissolved therein. The concentration of iron oxide in the waste form along with a high proportion of the iron in the waste form being present as Fe{sup 3+} provide a waste form exhibiting improved chemical resistance to corrosive attack. A method for preparing the improved iron phosphate waste forms is also provided. 21 figs.

  11. [Role of layered double hydroxide (LDH) in the protection of herring testis DNA from heavy metals].

    Science.gov (United States)

    Tang, Yi-Ni; Wu, Ping-Xiao; Zhu, Neng-Wu

    2012-10-01

    The role of layered double hydroxide (LDH) in the protection of herring testis DNA from heavy metals Cd2+ and Pb2+ was studied by X-ray diffraction ( XRD) spectra, Fourier transform infrared (FTIR) spectra, Scanning Electron Microscopy (SEM), Cyclic Voltammetry and Ultraviolet Spectrometry. Size expansion of the basal spacing (003) from 0. 76 nm in LDH to 2. 30 nm was observed in the resulting DNA-LDH nanohybrids and it gave peaks corresponding to C=O (1 534 cm(-1) and 1488 cm(-1)) in skeleton and bases, C-O stretching vibration (1228 cm(-1)), and P-O symmetrical stretching vibration (1096 cm(-1)) in functional groups of DNA, indicating that DNA were intercalated into the LDH by the ion exchange. However, the displacement of NO3(-) was not fully complete (partial intercalation of DNA). The DNA outside LDH interlayers was absorbed on the surface of LDH. The cyclic voltammetric curves showed that DNA in the composites exhibited a very similar peaks, which corresponded to the two reduction current peaks (E(P) = - 1.2 mV and E(P) = -2.4 mV) of free DNA. Also there was no cathode sag emerging in cyclic voltammetric curves, suggesting that both Cd2+ and Pb2+ cannot insert into the groove of DNA to associate with base pairs or other groups when DNA was bound on LDH. The results showed that, on the one hand, both Cd2+ and Pb2+ were absorbed on the external surface of LDH for immobilization, on the other hand, the layer of LDH provided ideal space for DNA by the action of protecting DNA molecules from Cd2+ and Pb2+.

  12. Process for the disposal of alkali metals

    International Nuclear Information System (INIS)

    Lewis, L.C.

    1979-01-01

    The invention describes a method of disposing of alkali metals by forming a solid waste for storage. The method comprises preparing an aqueous disposal solution of at least 55 weight percent alkali metal hydroxide, heating the alkali metal to melting temperature to form a feed solution, and spraying the molten feed solution into the disposal solution. The alkali metal reacts with the water in the disposal solution in a controlled reaction which produces alkali metal hydroxide, hydrogen and heat and thereby forms a solution of alkali metal hydroxides. Water is added to the solution in amounts sufficient to maintain the concentration of alkali metal hydroxides in the solution at 70 to 90 weight percent, and to maintain the temperature of the solution at about the boiling point. Removing and cooling the alkali metal hydroxide solution thereby forms a solid waste for storage. The method is particularly applicable to radioactive alkali metal reactor coolant. (auth)

  13. Layered Double Hydroxides as Effective Adsorbents for U(VI and Toxic Heavy Metals Removal from Aqueous Media

    Directory of Open Access Journals (Sweden)

    G. N. Pshinko

    2013-01-01

    Full Text Available Capacities of different synthesized Zn,Al-hydrotalcite-like adsorbents, including the initial carbonate [Zn4Al2(OH12]·CO3·8H2O and its forms intercalated with chelating agents (ethylenediaminetetraacetic acid (EDTA, diethylenetriaminepentaacetic acid (DTPA, and hexamethylenediaminetetraacetic acid (HMDTA and heat-treated form Zn4Al2O7, to adsorb uranium(VI and ions of toxic heavy metals have been compared. Metal sorption capacities of hydrotalcite-like adsorbents have been shown to correlate with the stability of their complexes with the mentioned chelating agents in a solution. The synthesized layered double hydroxides (LDHs containing chelating agents in the interlayer space are rather efficient for sorption purification of aqueous media free from U(VI irrespective of its forms of natural abundance (including water-soluble bi- and tricarbonate forms and from heavy metal ions. [Zn4Al2(OH12]·EDTA·nH2O is recommended for practical application as one of the most efficient and inexpensive synthetic adsorbents designed for recovery of both cationic and particularly important anionic forms of U(VI and other heavy metals from aqueous media. Carbonate forms of LDHs turned out to be most efficient for recovery of Cu(II from aqueous media with pH0≥7 owing to precipitation of Cu(II basic carbonates and Cu(II hydroxides. Chromate ions are efficiently adsorbed from water only by calcinated forms of LDHs.

  14. Processing method of radioactive metal wastes

    International Nuclear Information System (INIS)

    Uetake, Naoto; Urata, Megumu; Sato, Masao.

    1985-01-01

    Purpose: To reduce the volume and increase the density of radioactive metal wastes easily while preventing scattering of radioactivity and process them into suitable form to storage and treatment. Method: Metal wastes mainly composed of zirconium are discharged from nuclear power plants or fuel re-processing plants, and these metals such as zirconium and titanium vigorously react with hydrogen and rapidly diffuse as hydrides. Since the hydrides are extremely brittle and can be pulverized easily, they can be volume-reduced. However, since metal hydrides have no ductility, dehydrogenation is applied for the molding fabrication in view of the subsequent storage and processing. The dehydrogenation is easy like the hydrogenation and fine metal pieces can be molded in a small compression device. For the dehydrogenation, a temperature is slightly increased as compared with that in the hydrogenation, pressure is reduced through the vacuum evacuation system and the removed hydrogen is purified for reuse. The upper limit for the temperature of the hydrogenation is 680 0 C in order to prevent the scttering of radioactivity. (Kamimura, M.)

  15. Interfacial engineering of renewable metal organic framework derived honeycomb-like nanoporous aluminum hydroxide with tunable porosity.

    Science.gov (United States)

    Pan, Ye-Tang; Zhang, Lu; Zhao, Xiaomin; Wang, De-Yi

    2017-05-01

    Novel honeycomb-like mesoporous aluminum hydroxide (pATH) was synthesized via a facile one-step reaction by employing ZIF-8 as a template. This self-decomposing template was removed automatically under acidic conditions without the need for any tedious or hazardous procedures. Meanwhile, the pore size of pATH was easily modulated by tuning the dimensions of the ZIF-8 polyhedrons. Of paramount importance was the fact that the dissolved ZIF-8 in solution was regenerated upon deprotonation of the ligand under mild alkali conditions, and was reused in the preparation of pATH, thus forming a delicate synthesis cycle. The renewable template conferred cost-effective and sustainable features to the as-synthesized product. As a proof-of-concept application, the fascinating nanoporous structure enabled pATH to load more phosphorous-containing flame retardant and endowed better interaction with epoxy resin over that of commercial aluminum hydroxide. The limiting oxygen index, UL-94 vertical burning test and cone calorimeter test showed that the results of epoxy with the modified pATH rivalled those of epoxy with two times the loading amount of the commercial counterpart, while the former presented better mechanical properties. The proposed "amorphous replica method" used in this work will advance the potential for launching a vast area of research and technology development for the preparation of porous metal hydroxides for use in practical applications.

  16. A Non-Exploding Alkali Metal Drop on Water: From Blue Solvated Electrons to Bursting Molten Hydroxide.

    Science.gov (United States)

    Mason, Philip E; Buttersack, Tillmann; Bauerecker, Sigurd; Jungwirth, Pavel

    2016-10-10

    Alkali metals in water are always at the brink of explosion. Herein, we show that this vigorous reaction can be kept in a non-exploding regime, revealing a fascinating richness of hitherto unexplored chemical processes. A combination of high-speed camera imaging and visible/near-infrared/infrared spectroscopy allowed us to catch and characterize the system at each stage of the reaction. After gently placing a drop of a sodium/potassium alloy on water under an inert atmosphere, the production of solvated electrons became so strong that their characteristic blue color could be observed with the naked eye. The exoergic reaction leading to the formation of hydrogen and hydroxide eventually heated the alkali metal drop such that it became glowing red, and part of the metal evaporated. As a result of the reaction, a perfectly transparent drop consisting of molten hydroxide was temporarily stabilized on water through the Leidenfrost effect, bursting spectacularly after it had cooled sufficiently. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Heavy Metal Contamination Of Soils Around Municipal Solid Wastes ...

    African Journals Online (AJOL)

    Heavy Metal Contamination Of Soils Around Municipal Solid Wastes Dump In Port Harcourt, Nigeria. ... Global Journal of Environmental Sciences ... Soils around the waste dump were also contaminated as a result of continuous dispersion of heavy metals from the waste dump by run-off water, wind and scavengers.

  18. Mass-spectrometric study of ion clustering in alkali-metal hydroxide vapor: cluster-ion energy and structural characteristics

    International Nuclear Information System (INIS)

    Kudin, L.S.; Butman, M.F.; Krasnov, K.S.

    1986-01-01

    Various positive and negative ions have been recorded in the equilibrium vapors from alkali-metal hydroxides: M/sup +/-/, OH - , O - , MO - , MOH - , and X/sup +/-/ (MOH)/sub n/, where X = M/sup +/-/, OH - , n = 1-6. The equilibrium constants have been measured for X/sup +/-/(MOH)/sub n/ = x/sup +/-/ + nMOH(k), n = 1-3, and the enthalpies of reaction have been determined, from which the enthalpies of formation and dissociation energies of X/sup +/-/ (MOH)/sub n/ have been calculated. The relative stabilities of the ions in the series from Na to Cs are examined

  19. Aluminum Removal And Sodium Hydroxide Regeneration From Hanford Tank Waste By Lithium Hydrotalcite Precipitation Summary Of Prior Lab-Scale Testing

    International Nuclear Information System (INIS)

    Sams, T.L.; Guillot, S.

    2011-01-01

    Scoping laboratory scale tests were performed at the Chemical Engineering Department of the Georgia Institute of Technology (Georgia Tech), and the Hanford 222-S Laboratory, involving double-shell tank (DST) and single-shell tank (SST) Hanford waste simulants. These tests established the viability of the Lithium Hydrotalcite precipitation process as a solution to remove aluminum and recycle sodium hydroxide from the Hanford tank waste, and set the basis of a validation test campaign to demonstrate a Technology Readiness Level of 3.

  20. Formation of Layered Double Hydroxides on Alumina Surface in Aqueous Solutions Containing Divalent Metal Cations

    Czech Academy of Sciences Publication Activity Database

    Kovanda, F.; Mašátová, P.; Novotná, P.; Jirátová, Květa

    2009-01-01

    Roč. 57, č. 4 (2009), s. 425-432 ISSN 0009-8604 R&D Projects: GA ČR GA104/07/1400 Institutional research plan: CEZ:AV0Z40720504 Keywords : deposition * layered double hydroxides * supported mixed oxides Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.431, year: 2009

  1. Electrochemical corrosion testing of metal waste forms

    International Nuclear Information System (INIS)

    Abraham, D. P.; Peterson, J. J.; Katyal, H. K.; Keiser, D. D.; Hilton, B. A.

    1999-01-01

    Electrochemical corrosion tests have been conducted on simulated stainless steel-zirconium (SS-Zr) metal waste form (MWF) samples. The uniform aqueous corrosion behavior of the samples in various test solutions was measured by the polarization resistance technique. The data show that the MWF corrosion rates are very low in groundwaters representative of the proposed Yucca Mountain repository. Galvanic corrosion measurements were also conducted on MWF samples that were coupled to an alloy that has been proposed for the inner lining of the high-level nuclear waste container. The experiments show that the steady-state galvanic corrosion currents are small. Galvanic corrosion will, hence, not be an important mechanism of radionuclide release from the MWF alloys

  2. Monodisperse embedded nanoparticles derived from an atomic metal-dispersed precursor of layered double hydroxide for architectured carbon nanotube formation

    DEFF Research Database (Denmark)

    Tian, Gui-Li; Zhao, Meng-Qiang; Zhang, Bingsen

    2014-01-01

    understood. Herein, the preparation of metal NPs with tunable areal density from layered double hydroxide (LDH) precursors in which the metal cations were pre-dispersed at an atomic scale was explored. Large quantities of mesopores induced by the Kirkendall effect were formed on the as-calcined layered...... double oxide (LDO) flakes. The O atoms bonded with Fe3+ cations were easy to be extracted at a temperature higher than 750 degrees C, which greatly increased the mobility of Fe. Consequently, coalescence of the reduced Fe atoms into large NPs enhanced the Kirkendall effect, leading to the formation....... When the areal density was increased from 0.039 to 0.55, and to 2.1 x 10(15) m(-2), the Fe NPs embedded on the LDO flakes exhibited good catalytic performance for the growth of entangled carbon nanotubes (CNTs), aligned CNTs, and double helical CNTs, respectively. This work provides not only new...

  3. Efficient removal of dyes by a novel magnetic Fe{sub 3}O{sub 4}/ZnCr-layered double hydroxide adsorbent from heavy metal wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Dan; Li, Yang; Zhang, Jia [School of Environmental and Chemical Engineering, Shanghai University, No. 99 Shangda Road, Shanghai 200444 (China); Li, Wenhui [Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China); Zhou, Jizhi; Shao, Li [School of Environmental and Chemical Engineering, Shanghai University, No. 99 Shangda Road, Shanghai 200444 (China); Qian, Guangren, E-mail: grqian@shu.edu.cn [School of Environmental and Chemical Engineering, Shanghai University, No. 99 Shangda Road, Shanghai 200444 (China)

    2012-12-15

    Graphical abstract: To purify heavy metal wastewater (pickling waste liquor (PWL{sub A} and PWL{sub B}) and electroplating wastewater (EPW{sub C} and EPW{sub D})), a novel magnetic Fe{sub 3}O{sub 4}/ZnCr-LDH material was formed via two-step microwave hydrothermal method (Step 1 and Step 2) and applicable for organic dyes wastewater treatment. Highlights: Black-Right-Pointing-Pointer Fe{sub 3}O{sub 4}/ZnCr-layered double hydroxide adsorbent was produced from wastewater. Black-Right-Pointing-Pointer RSM was successfully applied to the optimization of the preparation conditions. Black-Right-Pointing-Pointer The maximum adsorption capacity of MO was found to be 240.16 mg/g. Black-Right-Pointing-Pointer The MO adsorption mechanism on MFLA was certified. Black-Right-Pointing-Pointer MFLA could be recycled after catalytic regeneration by the oxidation technology. - Abstract: A novel magnetic Fe{sub 3}O{sub 4}/ZnCr-layered double hydroxide adsorbent was produced from electroplating wastewater and pickling waste liquor via a two-step microwave hydrothermal method. Adsorption of methyl orange (MO) from water was studied using this material. The effects of three variables have been investigated by a single-factor method. The response surface methodology (RSM) based on Box-Behnken design was successfully applied to the optimization of the preparation conditions. The maximum adsorption capacity of MO was found to be 240.16 mg/g, indicating that this material may be an effective adsorbent. It was shown that 99% of heavy metal ions (Fe{sup 2+}, Fe{sup 3+}, Cr{sup 3+}, and Zn{sup 2+}) can be effectively removed into precipitates and released far less in the adsorption process. In addition, this material with adsorbed dye can be easily separated by a magnetic field and recycled after catalytic regeneration with advanced oxidation technology. Meanwhile, kinetic models, FTIR spectra and X-ray diffraction pattern were applied to the experimental data to examine uptake mechanism. The

  4. Comparative evaluation of short-term leach tests for heavy metal release from mineral processing waste

    Science.gov (United States)

    Al-Abed, S. R.; Hageman, P.L.; Jegadeesan, G.; Madhavan, N.; Allen, D.

    2006-01-01

    Evaluation of metal leaching using a single leach test such as the Toxicity Characteristic Leaching Procedure (TCLP) is often questionable. The pH, redox potential (Eh), particle size and contact time are critical variables in controlling metal stability, not accounted for in the TCLP. This paper compares the leaching behavior of metals in mineral processing waste via short-term extraction tests such as TCLP, Field Leach Test (FLT) used by USGS and deionized water extraction tests. Variation in the extracted amounts was attributed to the use of different particle sizes, extraction fluid and contact time. In the controlled pH experiments, maximum metal extraction was obtained at acidic pH for cationic heavy metals such as Cu, Pb and Zn, while desorption of Se from the waste resulted in high extract concentrations in the alkaline region. Precipitation of iron, caused by a pH increase, probably resulted in co-precipitation and immobilization of Cu, Pb and Zn in the alkaline pH region. A sequential extraction procedure was performed on the original waste and the solid residue from the Eh-pH experiments to determine the chemical speciation and distribution of the heavy metals. In the as-received waste, Cu existed predominantly in water soluble or sulfidic phases, with no binding to carbonates or iron oxides. Similar characteristics were observed for Pb and Zn, while Se existed mostly associated with iron oxides or sulfides. Adsorption/co-precipitation of Cu, Se and Pb on precipitated iron hydroxides was observed in the experimental solid residues, resulting in metal immobilization above pH 7.

  5. Fe(III) hydroxide nucleation and growth on quartz in the presence of Cu(II), Pb(II), and Cr(III): metal hydrolysis and adsorption.

    Science.gov (United States)

    Dai, Chong; Hu, Yandi

    2015-01-06

    Fe(III) hydroxide nanoparticles are an essential carrier for aqueous heavy metals. Particularly, iron hydroxide precipitation on mineral surfaces can immobilize aqueous heavy metals. Here, we used grazing-incidence small-angle X-ray scattering (GISAXS) to quantify nucleation and growth of iron hydroxide on quartz in 0.1 mM Fe(NO3)3 solution in the presence of Na(+), Cu(2+), Pb(2+), or Cr(3+) at pH = 3.7 ± 0.1. In 30 min, the average radii of gyration (R(g)) of particles on quartz grew from around 2 to 6 nm in the presence of Na(+) and Cu(2+). Interestingly, the particle sizes remained 3.3 ± 0.3 nm in the presence of Pb(2+), and few particles formed in the presence of Cr(3+). Quartz crystal microbalance dissipation (QCM-D) measurements showed that only Cr(3+) adsorbed onto quartz, while Cu(2+) and Pb(2+) did not. Cr(3+) adsorption changed the surface charge of quartz from negative to positive, thus inhibiting the precipitation of positively charged iron hydroxide on quartz. Masses and compositions of the precipitates were also quantified. This study provided new insights on interactions among quartz, iron hydroxide, and metal ions. Such information is helpful not only for environmental remediation but also for the doping design of iron oxide catalysts.

  6. Defining a metal-based waste form for IFR pyroprocessing wastes

    International Nuclear Information System (INIS)

    McDeavitt, S.M.; Park, J.Y.; Ackerman, J.P.

    1994-01-01

    Pyrochemical electrorefining to recover actinides from metal nuclear fuel is a key element of the Integral Fast Reactor (IFR) fuel cycle. The process separates the radioactive fission products from the long-lived actinides in a molten LiCl-KCl salt, and it generates a lower waste volume with significantly less long-term toxicity as compared to spent nuclear fuel. The process waste forms include a mineral-based waste form that will contain fission products removed from an electrolyte salt and a metal-based waste form that will contain metallic fission products and the fuel cladding and process materials. Two concepts for the metal-based waste form are being investigated: (1) encapsulating the metal constituents in a Cu-Al alloy and (2) alloying the metal constituents into a uniform stainless steel-based waste form. Results are given from our recent studies of these two concepts

  7. Plasma arc systems for waste treatment and metal recovery

    Science.gov (United States)

    Eschenbach, Richard C.

    1996-06-01

    Plasma torches are being used for treating very difficult wastes,for recovering metal values from metallurgical wastes, and for making high-quality ingots and powder in the special metals industry. This article discusses the process requirements and the state of the art for plasma arc systems in each of these fields.

  8. Waste printing paper as analogous adsorbents for heavy metals in ...

    African Journals Online (AJOL)

    user

    Waste printing paper as analogous adsorbents for heavy metals in aqueous solution. Moyib, O. K.. 1. *, Ayedun. 1. , M. A. ... ABSTRACT. Waste printing paper (WPP) is an abundant local waste material that requires end-use channelling to reduce ..... Science and Technology, 19 2007) 69. 20. Ahalya N., Ramachandra, T. V., ...

  9. Production of calcium hydroxide from the waste of Cariri stone; Producao de hidroxido de calcio a partir de residuo da pedra Cariri

    Energy Technology Data Exchange (ETDEWEB)

    Alves, T.M.E.; Santos, A.M.M.; Brasileiro, M.I.; Pinheiro, S.F.L.; Prado, A.C.A., E-mail: tiagomaiaea@gmail.com [Universidade Federal do Cariri (UFCA), Juazeiro do Norte, CE (Brazil)

    2016-07-01

    The extraction of Cariri stone in the northeast is a frequent activity because of its ornamental application as well as for the construction sector. However, by this extraction, untapped waste formation grows and becomes a problem for the environment. The objective of this work is to produce calcium hydroxide, from this limestone residue, with controlled porosity, solubility and particle size. The waste was characterized with X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF) and thermal analysis (TGA). The limestone was calcined at 850°C and 950°C for 45 minutes and three hours, being characterized by XRD, XRF and TGA. Once calcined, it was hydrated with 17,5g and 22g oxide to 100mL water and manually mixed for 15 and 25 minutes. The calcium hydroxides have been submitted for tests in vivo in rats and will be characterized by XRD, Scanning Electron Microscopy (SEM) and Infrared. (author)

  10. Magnesium Hydroxide

    Science.gov (United States)

    Magnesium hydroxide is used on a short-term basis to treat constipation.This medication is sometimes prescribed ... Magnesium hydroxide come as a tablet and liquid to take by mouth. It usually is taken as ...

  11. Aluminum Hydroxide

    Science.gov (United States)

    Aluminum hydroxide is used for the relief of heartburn, sour stomach, and peptic ulcer pain and to ... Aluminum hydroxide comes as a capsule, a tablet, and an oral liquid and suspension. The dose and ...

  12. Melting tests for recycling of radioactive metal wastes

    International Nuclear Information System (INIS)

    Nakamura, Hisashi; Kanazawa, Katsuo; Fujiki, Kazuo

    1995-01-01

    To allow the future recycling of decommissioning wastes to promote smoothly, melting tests were conducted using metal wastes and simulated wastes with radioisotopes. The test results indicate that the transfer behavior of radionuclides during melting is basically understood by considering the volatility and oxidizable tendency of each radionuclide. The partitioning of some radionuclides into products was influenced by the melting process of wastes. The radioactivity distribution in ingots was uniform regardless of the kinds of radionuclide. (author)

  13. Effects of metal salt addition on odor and process stability during the anaerobic digestion of municipal waste sludge.

    Science.gov (United States)

    Abbott, Timothy; Eskicioglu, Cigdem

    2015-12-01

    Anaerobic digestion (AD) is an effective way to recover energy and nutrients from organic waste; however, several issues including the solubilization of bound nutrients and the production of corrosive, highly odorous and toxic volatile sulfur compounds (VSCs) in AD biogas can limit its wider adoption. This study explored the effects of adding two different doses of ferric chloride, aluminum sulfate and magnesium hydroxide directly to the feed of complete mix semi-continuously fed mesophilic ADs on eight of the most odorous VSCs in AD biogas at three different organic loading rates (OLR). Ferric chloride was shown to be extremely effective in reducing VSCs by up to 87%, aluminum sulfate had the opposite effect and increased VSC levels by up to 920%, while magnesium hydroxide was not shown to have any significant impact. Ferric chloride, aluminum sulfate and magnesium hydroxide were effective in reducing the concentration of orthophosphate in AD effluent although both levels of alum addition caused digester failure at elevated OLRs. Extensive foaming was observed within the magnesium hydroxide dosed digesters, particularly at higher doses and high OLRs. Certain metal salt additions may be a valuable tool in overcoming barriers to AD and to meet regulatory targets. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Methods for recovering metals from electronic waste, and related systems

    Energy Technology Data Exchange (ETDEWEB)

    Lister, Tedd E; Parkman, Jacob A; Diaz Aldana, Luis A; Clark, Gemma; Dufek, Eric J; Keller, Philip

    2017-10-03

    A method of recovering metals from electronic waste comprises providing a powder comprising electronic waste in at least a first reactor and a second reactor and providing an electrolyte comprising at least ferric ions in an electrochemical cell in fluid communication with the first reactor and the second reactor. The method further includes contacting the powders within the first reactor and the second reactor with the electrolyte to dissolve at least one base metal from each reactor into the electrolyte and reduce at least some of the ferric ions to ferrous ions. The ferrous ions are oxidized at an anode of the electrochemical cell to regenerate the ferric ions. The powder within the second reactor comprises a higher weight percent of the at least one base metal than the powder in the first reactor. Additional methods of recovering metals from electronic waste are also described, as well as an apparatus of recovering metals from electronic waste.

  15. Volume Reduction of Decommissioning Radioactive Burnable and Metal Wastes

    International Nuclear Information System (INIS)

    Min, B. Y.; Lee, Y. J.; Yun, G. S.; Lee, K. W.; Moon, J. K.; Choi, Y. K.; Cho, J. H.

    2014-01-01

    A large quantity of radioactive waste was generated during the decommissioning projects. For the purpose of the volume reduction and clearance for decommissioning wastes from decommissioning projects, the incineration and high melting technology has been selected for the decommissioning wastes treatment. The volume reduction of the combustible wastes through the incineration technologies has merits from the view point of a decrease in the amount of waste to be disposed of resulting in a reduction of the disposal cost. Incineration is generally accepted as a method of reducing the volume of radioactive waste. The incineration technology is an effective treatment method that contains hazardous chemicals as well as radioactive contamination. Incinerator burns waste at high temperature. Incineration of a mixture of chemically hazardous and radioactive materials, known as 'mixed waste,' has two principal goals: to reduce the volume and total chemical toxicity of the waste. Incineration itself does not destroy the metals or reduce the radioactivity of the waste. A proven melting technology is currently used for low-level waste (LLW) at several facilities worldwide. These facilities use melting as a means of processing LLW for unrestricted release of the metal or for recycling within the nuclear sector. About 16.4 tons of decommissioning combustible waste has been treated using Oxygen Enriched incineration. The incineration facility operated quite smoothly through the analysis major critical parameters of off-gas

  16. Thermal and hydrometallurgical recovery methods of heavy metals from municipal solid waste fly ash.

    Science.gov (United States)

    Kuboňová, L; Langová, Š; Nowak, B; Winter, F

    2013-11-01

    Heavy metals in fly ash from municipal solid waste incinerators are present in high concentrations. Therefore fly ash must be treated as a hazardous material. On the other hand, it may be a potential source of heavy metals. Zinc, lead, cadmium, and copper can be relatively easily removed during the thermal treatment of fly ash, e.g. in the form of chlorides. In return, wet extraction methods could provide promising results for these elements including chromium and nickel. The aim of this study was to investigate and compare thermal and hydrometallurgical treatment of municipal solid waste fly ash. Thermal treatment of fly ash was performed in a rotary reactor at temperatures between 950 and 1050°C and in a muffle oven at temperatures from 500 to 1200°C. The removal more than 90% was reached by easy volatile heavy metals such as cadmium and lead and also by copper, however at higher temperature in the muffle oven. The alkaline (sodium hydroxide) and acid (sulphuric acid) leaching of the fly ash was carried out while the influence of temperature, time, concentration, and liquid/solid ratio were investigated. The combination of alkaline-acidic leaching enhanced the removal of, namely, zinc, chromium and nickel. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Electrodialytic Removal of Heavy Metals from Different Solid Waste Products

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Christensen, Iben Vernegren; Pedersen, Anne Juul

    2003-01-01

    A variety of heavy metal polluted waste products must be handled today. Electrochemical methods have been developed for remediation of polluted soil. One of the methods is the electrodialytic remediation method that is based on electromigration of heavy metal ions and ionic species within the soil...... could be used when removing Cu and Cr from a soil with 25% carbonates. The final concentrations of the elements were below the target values after the remediation. A question of whether the electrodialytic remediation method can be used for other waste products arose. Preliminary experiments showed...... that the method could be used for removal of different heavy metals from impregnated wood waste, fly ash from straw combustion, and fly ash from municipal solid waste incineration. The best result was obtained with the wood waste where more than 80% of each of the polluting elements Cu, Cr and As was removed...

  18. Adsorption of heavy metals by agroforestry waste derived activated ...

    African Journals Online (AJOL)

    Adsorption of heavy metals by agroforestry waste derived activated carbons applied to aqueous solutions. Jane M Misihairabgwi, Abisha Kasiyamhuru, Peter Anderson, Colin J Cunningham, Tanya A Peshkur, Ignatious Ncube ...

  19. [Determination of total mass and morphology analysis of heavy metal in soil with potassium biphthalate-sodium hydroxide by ICP-AES].

    Science.gov (United States)

    Qu, Jiao; Yuan, Xing; Cong, Qiao; Wang, Shuang

    2008-11-01

    Blank soil was used as quality controlling samples, soil sample dealt by potassium biphthalate-sodium hydroxide buffer solution was used as check sample, mixed acid HNO3-HF-HClO4 was chosen to nitrify soil samples, and plasma emission spectrometer (ICP-AES) was used as detecting method. The authors determined the total metal mass of Mo, Pb, As, Hg, Cr, Cd, Zn, Cu and Ni in the extracted and dealt soil samples, and determined the mass of Mo, Pb, As, Hg, Cr, Cd, Zn, Cu and Ni in the three chemical morphologies, including acid extractable morphology, oxide associated morphology, and organics associated modality. The experimental results indicated that the different pH of potassium biphthalate-sodium hydroxide buffer solution had obvious influence on the total mass of heavy metal and morphology transformation. Except for metal element Pb and Zn, the addition of different pH potassium dihydrogen phosphate-sodium hydroxide buffer solution could accelerate the soil samples nitrification and the total mass determination of heavy metal in the soil samples. The potassium biphthalate-sodium hydroxide buffer solution could facilitate the acid extractable morphology of Cr, Cu, Hg and Pb, oxidation associated morphology of As, Hg, Pb and Zn and the organic associated morphology transforming of As and Hg. At pH 5.8, the maximum acid extractable morphology contents of Cu and Hg were 2.180 and 0.632 mg x kg(-1), respectively; at pH 6.2, the maximal oxidation associated morphology content of Pb could achieve 27.792 mg x kg(-1); at pH 6.0, the maximum organic associated morphology content of heavy metal Hg was 4.715 mg x kg(-1).

  20. Waste printing paper as analogous adsorbents for heavy metals in ...

    African Journals Online (AJOL)

    Waste printing paper (WPP) is an abundant local waste material that requires end-use channelling to reduce environmental pollution. In the present study, removal of cadmium (II) (Cd2+), copper (II) (Cu2+), nickel (II) (Ni2+) and lead (II) ions (Pb2+) from aqueous solution by WPP at varying incubating period, metal dosage ...

  1. SOLIDIFICATION OF THE HANFORD LAW WASTE STREAM PRODUCED AS A RESULT OF NEAR-TANK CONTINUOUS SLUDGE LEACHING AND SODIUM HYDROXIDE RECOVERY

    Energy Technology Data Exchange (ETDEWEB)

    Reigel, M.; Johnson, F.; Crawford, C.; Jantzen, C.

    2011-09-20

    The U.S. Department of Energy (DOE), Office of River Protection (ORP), is responsible for the remediation and stabilization of the Hanford Site tank farms, including 53 million gallons of highly radioactive mixed wasted waste contained in 177 underground tanks. The plan calls for all waste retrieved from the tanks to be transferred to the Waste Treatment Plant (WTP). The WTP will consist of three primary facilities including pretreatment facilities for Low Activity Waste (LAW) to remove aluminum, chromium and other solids and radioisotopes that are undesirable in the High Level Waste (HLW) stream. Removal of aluminum from HLW sludge can be accomplished through continuous sludge leaching of the aluminum from the HLW sludge as sodium aluminate; however, this process will introduce a significant amount of sodium hydroxide into the waste stream and consequently will increase the volume of waste to be dispositioned. A sodium recovery process is needed to remove the sodium hydroxide and recycle it back to the aluminum dissolution process. The resulting LAW waste stream has a high concentration of aluminum and sodium and will require alternative immobilization methods. Five waste forms were evaluated for immobilization of LAW at Hanford after the sodium recovery process. The waste forms considered for these two waste streams include low temperature processes (Saltstone/Cast stone and geopolymers), intermediate temperature processes (steam reforming and phosphate glasses) and high temperature processes (vitrification). These immobilization methods and the waste forms produced were evaluated for (1) compliance with the Performance Assessment (PA) requirements for disposal at the IDF, (2) waste form volume (waste loading), and (3) compatibility with the tank farms and systems. The iron phosphate glasses tested using the product consistency test had normalized release rates lower than the waste form requirements although the CCC glasses had higher release rates than the

  2. Solidification Of The Hanford Law Waste Stream Produced As A Result Of Near-Tank Continuous Sludge Leaching And Sodium Hydroxide Recovery

    International Nuclear Information System (INIS)

    Reigel, M.; Johnson, F.; Crawford, C.; Jantzen, C.

    2011-01-01

    The U.S. Department of Energy (DOE), Office of River Protection (ORP), is responsible for the remediation and stabilization of the Hanford Site tank farms, including 53 million gallons of highly radioactive mixed wasted waste contained in 177 underground tanks. The plan calls for all waste retrieved from the tanks to be transferred to the Waste Treatment Plant (WTP). The WTP will consist of three primary facilities including pretreatment facilities for Low Activity Waste (LAW) to remove aluminum, chromium and other solids and radioisotopes that are undesirable in the High Level Waste (HLW) stream. Removal of aluminum from HLW sludge can be accomplished through continuous sludge leaching of the aluminum from the HLW sludge as sodium aluminate; however, this process will introduce a significant amount of sodium hydroxide into the waste stream and consequently will increase the volume of waste to be dispositioned. A sodium recovery process is needed to remove the sodium hydroxide and recycle it back to the aluminum dissolution process. The resulting LAW waste stream has a high concentration of aluminum and sodium and will require alternative immobilization methods. Five waste forms were evaluated for immobilization of LAW at Hanford after the sodium recovery process. The waste forms considered for these two waste streams include low temperature processes (Saltstone/Cast stone and geopolymers), intermediate temperature processes (steam reforming and phosphate glasses) and high temperature processes (vitrification). These immobilization methods and the waste forms produced were evaluated for (1) compliance with the Performance Assessment (PA) requirements for disposal at the IDF, (2) waste form volume (waste loading), and (3) compatibility with the tank farms and systems. The iron phosphate glasses tested using the product consistency test had normalized release rates lower than the waste form requirements although the CCC glasses had higher release rates than the

  3. Treatment and minimization of heavy metal-containing wastes 1995

    International Nuclear Information System (INIS)

    Hager, J.P.; Mishra, B.; Litz, J.L.

    1995-01-01

    This symposium was held in conjunction with the 1995 Annual Meeting of the Minerals, Metals and Materials Society in Las Vegas, Nevada, February 12--16, 1995. The purpose of this meeting was to provide a forum for exchange of state-of-the-art information on treating and minimizing heavy metal-containing wastes. Papers were categorized under the following broad headings: aqueous processing; waste water treatment; thermal processing and stabilization; processing of fly ash, flue dusts, and slags; and processing of lead, mercury, and battery wastes. Individual papers have been processed separately for inclusion in the appropriate data bases

  4. PASSIVATION LAYER STABILITY OF A METALLIC ALLOY WASTE FORM

    International Nuclear Information System (INIS)

    Williamson, M.; Mickalonis, J.; Fisher, D.; Sindelar, R.

    2010-01-01

    Alloy waste form development under the Waste Forms Campaign of the DOE-NE Fuel Cycle Research and Development program includes the process development and characterization of an alloy system to incorporate metal species from the waste streams generated during nuclear fuel recycling. This report describes the tests and results from the FY10 activities to further investigate an Fe-based waste form that uses 300-series stainless steel as the base alloy in an induction furnace melt process to incorporate the waste species from a closed nuclear fuel recycle separations scheme. This report is focused on the initial activities to investigate the formation of oxyhydroxide layer(s) that would be expected to develop on the Fe-based waste form as it corrodes under aqueous repository conditions. Corrosion tests were used to evaluate the stability of the layer(s) that can act as a passivation layer against further corrosion and would affect waste form durability in a disposal environment.

  5. Constraints on Metal Oxide and Metal Hydroxide Abundances in the Winds of AGB Stars: Potential Detection of FeO in R Dor

    Science.gov (United States)

    Decin, L.; Danilovich, T.; Gobrecht, D.; Plane, J. M. C.; Richards, A. M. S.; Gottlieb, C. A.; Lee, K. L. K.

    2018-03-01

    Using the Atacama Large Millimeter/submillimeter Array (ALMA), we observed the stellar wind of two oxygen-rich asymptotic giant branch stars, IK Tau and R Dor, between 335 and 362 GHz. One aim was to detect metal oxides and metal hydroxides (AlO, AlOH, FeO, MgO, and MgOH), some of which are thought to be direct precursors of dust nucleation and growth. We report on the potential first detection of FeO (v = 0, Ω = 4, J = 11–10) in R Dor (mass-loss rate \\dot{M} ∼ 1 × 10‑7 M ⊙ yr‑1). The presence of FeO in IK Tau (\\dot{M} ∼ 5 × 10‑6 M ⊙ yr‑1) cannot be confirmed, due to a blend with 29SiS, a molecule that is absent in R Dor. The detection of AlO in R Dor and of AlOH in IK Tau was reported earlier by Decin et al. All other metal oxides and hydroxides, as well as MgS, remain undetected. We derive a column density N(FeO) of 1.1 ± 0.9 × 1015 cm‑2 in R Dor, or a fractional abundance [FeO/H] ∼ 1.5 × 10‑8 accounting for non-local thermodynamic equilibrium effects. The derived fractional abundance [FeO/H] is a factor ∼20 larger than conventional gas-phase chemical-kinetic predictions. This discrepancy may be partly accounted for by the role of vibrationally excited OH in oxidizing Fe, or it may be evidence for other currently unrecognized chemical pathways producing FeO. Assuming a constant fractional abundance w.r.t. H2, the upper limits for the other metals are [MgO/H2] < 5.5 × 10‑10 (R Dor) and <7 × 10‑11 (IK Tau), [MgOH/H2] < 9 × 10‑9 (R Dor) and <1 × 10‑9 (IK Tau), [CaO/H2] < 2.5 × 10‑9 (R Dor) and <1 × 10‑10 (IK Tau), [CaOH/H2] < 6.5 × 10‑9 (R Dor) and <9 × 10‑10 (IK Tau), and [MgS/H2] < 4.5 × 10‑10 (R Dor) and <6 × 10‑11 (IK Tau). The retrieved upper-limit abundances for these latter molecules are in accord with the chemical model predictions.

  6. Evaluation of some heavy metals concentration in municipal waste ...

    African Journals Online (AJOL)

    A study was conducted in Delta State, a major Niger Delta region of Nigeria. The aim was to evaluate some heavy metals concentration in municipal wastes dumpsites that are presently used for intensive horticultural crops production. The heavy metals studied were; Iron (Fe); Lead (Pb); Mercury (Hg); Cromium (Cr); Nickel ...

  7. Embedding methods of solidified waste in metal matrices

    International Nuclear Information System (INIS)

    Neumann, W.

    1979-01-01

    The embedding of simulated waste calcines by three different methods (vacuum-pressure casting, centrifugal casting, and metal stirred with the calcines) was investigated. The experimental performance is described and advantages and disadvantages noted. The feasibility of embedding fines by stirring in metal was shown. In addition, an estimation of the influence of porosity on the properties of composites was carried out

  8. Measurement of total alpha activity of neptunium, plutonium, and americium in highly radioactive Hanford waste by iron hydroxide precipitation and 2-heptanone solvent extraction

    International Nuclear Information System (INIS)

    Maiti, T.C.; Kaye, J.H.

    1992-06-01

    An improved method has been developed to concentrate the major alpha-emitting actinide elements neptunium, plutonium, and americium from samples with high salt content such as those resulting from efforts to characterize Hanford storage tank waste. Actinide elements are concentrated by coprecipitation of their hydroxides using iron carrier. The iron is removed by extraction from 8M HCI with 2-heptanone. The actinide elements remain in the aqueous phase free from salts, iron, and long-lived fission products. Recoveries averaged 98 percent

  9. The Recovery of Zinc Heavy Metal from Industrial Liquid Waste

    International Nuclear Information System (INIS)

    Panggabean, Sahat M.

    2000-01-01

    It had been studied the recovery of zinc heavy metal from liquid waste of electroplating industry located at East Jakarta. The aim of this study was to minimize the waste arisen from industrial activities by taking out zinc metal in order to reused on-site. The method of recovery was two steps precipitation using NaOH reagent and pH variation. The first step of precipitation at pH optimum around 6 yielded iron metal. The second step at pH optimum around 10 yielded zinc metal. The zinc metal was taken out assessed to the possibility of reused at that fabric. By applying its, it will yield the volume reduction of sludge waste about 36.1% or 53.2% of zinc metal containing in the waste. It means the cost of waste treatment will be lower. Beside its, the effluent arisen from the method had fulfill the maximum limit and it allowed to release to the environment. (author)

  10. Growth of PbTe nanorods controlled by polymerized tellurium anions and metal(II) amides via composite-hydroxide-mediated approach

    International Nuclear Information System (INIS)

    Wan Buyong; Hu Chenguo; Liu Hong; Xiong Yufeng; Li Feiyun; Xi Yi; He Xiaoshan

    2009-01-01

    The pure face-centered-cubic PbTe nanorods have been synthesized by the composite-hydroxide-mediated approach using hydrazine as a reducing agent. The method is based on reaction among reactants in the melts of potassium hydroxide and sodium hydroxide eutectic at 170-220 deg. C and normal atmosphere without using any organic dispersant or surface-capping agent. Scanning electron microscopy, X-ray diffraction, transmission electron microscopy, and energy dispersive X-ray spectroscopy were used to characterize the structure, morphology and composition of the samples. The diameters of nanorods are almost fixed, while the lengths can be tunable under different growth time and temperatures. The growth mechanism of PbTe nanorods is investigated via UV-vis absorption, demonstrating that polymerized tellurium anions and metal(II) amides in the hydrazine hydroxide melts could control the crystallization and growth process of PbTe nanostructures. The band gap of as-synthesized PbTe nanorods has been calculated based on UV-vis-NIR optical diffuse reflectance spectra data.

  11. Epsilon metal waste form for immobilization of noble metals from used nuclear fuel

    Science.gov (United States)

    Crum, Jarrod V.; Strachan, Denis; Rohatgi, Aashish; Zumhoff, Mac

    2013-10-01

    Epsilon metal (ɛ-metal), an alloy of Mo, Pd, Rh, Ru, and Tc, is being developed as a waste form to treat and immobilize the undissolved solids and dissolved noble metals from aqueous reprocessing of commercial used nuclear fuel. Epsilon metal is an attractive waste form for several reasons: increased durability relative to borosilicate glass, it can be fabricated without additives (100% waste loading), and in addition it also benefits borosilicate glass waste loading by eliminating noble metals from the glass, thus the processing problems related to their insolubility in glass. This work focused on the processing aspects of the epsilon metal waste form development. Epsilon metal is comprised of refractory metals resulting in high alloying temperatures, expected to be 1500-2000 °C, making it a non-trivial phase to fabricate by traditional methods. Three commercially available advanced technologies were identified: spark-plasma sintering, microwave sintering, and hot isostatic pressing, and investigated as potential methods to fabricate this waste form. Results of these investigations are reported and compared in terms of bulk density, phase assemblage (X-ray diffraction and elemental analysis), and microstructure (scanning electron microscopy).

  12. Methods for recovering precious metals from industrial waste

    Science.gov (United States)

    Canda, L.; Heput, T.; Ardelean, E.

    2016-02-01

    The accelerated rate of industrialization increases the demand for precious metals, while high quality natural resources are diminished quantitatively, with significant operating costs. Precious metals recovery can be successfully made from waste, considered to be secondary sources of raw material. In recent years, concerns and interest of researchers for more increasing efficient methods to recover these metals, taking into account the more severe environmental protection legislation. Precious metals are used in a wide range of applications, both in electronic and communications equipment, spacecraft and jet aircraft engines and for mobile phones or catalytic converters. The most commonly recovered precious metals are: gold from jewellery and electronics, silver from X- ray films and photographic emulsions, industrial applications (catalysts, batteries, glass/mirrors), jewellery; platinum group metals from catalytic converters, catalysts for the refining of crude oil, industrial catalysts, nitric acid manufacturing plant, the carbon-based catalyst, e-waste. An important aspect is the economic viability of recycling processes related to complex waste flows. Hydrometallurgical and pyrometallurgical routes are the most important ways of processing electrical and electronic equipment waste. The necessity of recovering precious metals has opened new opportunities for future research.

  13. XPS characterization of the anodic oxide film formed on uranium metal in sodium hydroxide solution

    International Nuclear Information System (INIS)

    Fu Xiaoguo; Wang Xiaolin; Guo Huanjun; Wang Qingfu; Zhao Zhengping; Zhong Yongqiang

    2002-01-01

    X-ray photoelectron spectroscopy (XPS) is used to examine the anodic oxide film formed on uranium metal in 0.8 mol/L NaOH solution. The U4f 7/2 fitting spectra suggests that the anodic oxide film is composed of uranium trioxide and a small amount of UO 2+x . Under UHV condition, the U4f peak shifts to the lower binding energy, while a gradual increase in the intensity of U5f peak and the broad of U4f peak are also observed. All of these changes are due to reduction of uranium trioxide in the anodic oxide film. XPS quantitative analysis confirms the occurrence of reduction reaction

  14. Melt-decontamination method for radioactive metal wastes

    International Nuclear Information System (INIS)

    Otsuka, Hisao; Izumida, Tatsuo; Kondo, Yasuo; Fujii, Norihisa; Tsuchiya, Hiroyuki.

    1997-01-01

    When metals contaminated by radioactive materials are melted by heating with addition of slugs, the weight ratio of basic slugs to acidic slugs constituting the molten slugs is controlled to from 0.5 to 0.3, and the transfer of radioactive materials in the molten metals to the slug phase is promoted. Then, Co, Ni and/or Cr as radioactive materials are removed. The temperature of the molten metals is controlled to higher than the melting point of the metals and lower than the decomposition point of oxides of the radioactive materials. With such procedures, not only Co but also a plurality of nuclides to be removed from the radioactive metal wastes can be decontaminated simultaneously, the operation is simplified and the amount of secondary wastes upon decontamination can be reduced. (T.M.)

  15. Adsorption of tetracycline on Fe (hydr)oxides: effects of pH and metal cation (Cu2+, Zn2+ and Al3+) addition in various molar ratios

    Science.gov (United States)

    Hsu, Liang-Ching; Liu, Yu-Ting; Syu, Chien-Hui; Huang, Mei-Hsia; Teah, Heng Yi

    2018-01-01

    Iron (Fe) (hydr)oxides control the mobility and bioavailability of tetracycline (TC) in waters and soils. Adsorption of TC on Fe (hydr)oxides is greatly affected by polyvalent metals; however, impacts of molar metal/TC ratios on TC adsorptive behaviours on Fe (hydr)oxides remain unclear. Results showed that maximum TC adsorption on ferrihydrite and goethite occurred at pH 5–6. Such TC adsorption was generally promoted by the addition of Cu2+, Zn2+ and Al3+. The greatest increase in TC adsorption was found in the system with molar Cu/TC ratio of 3 due to the formation of Fe hydr(oxide)–Cu–TC ternary complexes. Functional groups on TC that were responsible for the complexation with Cu2+shifted from phenolic diketone groups at Cu/TC molar ratio adsorption at a molar Al/TC ratio of 1. However, TC adsorption decreased for Al/TC molar ratio > 1 as excess Al3+ led to the competitive adsorption with Al/TC complexes. For the Zn2+ addition, no significant correlation was found between TC adsorption capacity and molar Zn/TC ratios. PMID:29657795

  16. Hydrogen production coupled to nuclear waste treatment: the safe treatment of alkali metals through a well-demonstrated process

    International Nuclear Information System (INIS)

    Rahier, A.; Mesrobian, G.

    2006-01-01

    In 1992, the United Nations emphasised the urgent need to act against the perpetuation of disparities between and within nations, the worsening of poverty, hunger, ill health and illiteracy and the continuing deterioration of ecosystems on which we depend for our well-being. In this framework, taking into account the preservation of both worldwide energy resources and ecosystems, the use of nuclear energy to produce clean energy carriers, such as hydrogen, is undoubtedly advisable. However, coping fully with the Agenda 21 statements requires defining adequate treatment processes for nuclear wastes. This paper discusses the possible use of a well-demonstrated process to convert radioactively contaminated alkali metals into sodium hydroxide while producing hydrogen. We conclude that a synergy between Chlor-Alkali specialists and nuclear specialists may help find an acceptable solution for radioactively contaminated sodium waste. (author)

  17. Bio-extraction of precious metals from urban solid waste

    Science.gov (United States)

    Das, Subhabrata; Natarajan, Gayathri; Ting, Yen-Peng

    2017-01-01

    Reduced product lifecycle and increasing demand for electronic devices have resulted in the generation of huge volumes of electronic waste (e-waste). E-wastes contain high concentrations of toxic heavy metals, which have detrimental effects on health and the environment. However, e-wastes also contain significant concentrations of precious metals such as gold, silver and palladium, which can be a major driving force for recycling of urban waste. Cyanogenic bacteria such as Chromobacterium violaceum generate cyanide as a secondary metabolite which mobilizes gold into solution via a soluble gold-cyanide complex. However, compared to conventional technology for metal recovery, this approach is not effective, owing largely to the low concentration of lixiviants produced by the bacteria. To overcome the challenges of bioleaching of gold from e-waste, several strategies were adopted to enhance gold recovery rates. These included (i) pretreatment of e-waste to remove competing metal ions, (ii) mutation to adapt the bacteria to high pH environment, (iii) metabolic engineering to produce higher cyanide lixiviant, and (iv) spent medium leaching with adjusted initial pH. Compared to 7.1 % recovery by the wild type bacteria, these strategies achieved gold recoveries of 11.3%, 22.5%, 30% and 30% respectively at 0.5% w/v pulp density respectively. Bioleached gold was finally mineralized and precipitated as gold nanoparticles using the bacterium Delftia acidovorans. This study demonstrates the potential for enhancement of biocyanide production and gold recovery from electronic waste through different strategies, and extraction of solid gold from bioleached leachate.

  18. Separating and recycling metals from mixed metallic particles of crushed electronic wastes by vacuum metallurgy.

    Science.gov (United States)

    Zhan, Lu; Xu, Zhenming

    2009-09-15

    During the treatment of electronic wastes, a crushing process is usually used to strip metals from various base plates. Several methods have been applied to separate metals from nonmetals. However, mixed metallic particles obtained from these processes are still a mixture of various metals, including some toxic heavy metals such as lead and cadmium. With emphasis on recovering copper and other precious metals, there have hitherto been no satisfactory methods to recover these toxic metals. In this paper, the criterion of separating metals from mixed metallic particles by vacuum metallurgy is built. The results show that the metals with high vapor pressure have been almost recovered completely, leading to a considerable reduction of environmental pollution. In addition, the purity of copper in mixed particles has been improved from about 80 wt % to over 98 wt %.

  19. Electrolytic decontamination of metal low level waste (LLW) and mixed low level waste (MLLW)

    International Nuclear Information System (INIS)

    1998-01-01

    Metal objects resulting from ER activities were decontaminated using electrolytic methods. The project involved about 500 kg of ballistic test projectiles, 23 augers and drill heads, and 50 pieces of shrapnel containing lead. All objects were free-released and either reclaimed as scrap metal or reused. Electrolytic decontamination was proven to be an effective method to decontaminate metal waste objects to free-release standards. A cost analysis showed the process to be economical, especially when applied to decontamination of mixed waste, TRU waste, or when the recovered materials could be reused or recycled. The cost of decontamination of scrap iron is approximately equal to the cost of its land disposal as low level waste

  20. Method of handling radioactive alkali metal waste

    Science.gov (United States)

    Wolson, R.D.; McPheeters, C.C.

    Radioactive alkali metal is mixed with particulate silica in a rotary drum reactor in which the alkali metal is converted to the monoxide during rotation of the reactor to produce particulate silica coated with the alkali metal monoxide suitable as a feed material to make a glass for storing radioactive material. Silica particles, the majority of which pass through a 95 mesh screen or preferably through a 200 mesh screen, are employed in this process, and the preferred weight ratio of silica to alkali metal is 7 to 1 in order to produce a feed material for the final glass product having a silica to alkali metal monoxide ratio of about 5 to 1.

  1. Method of handling radioactive alkali metal waste

    International Nuclear Information System (INIS)

    Mcpheeters, C.C.; Wolson, R.D.

    1980-01-01

    Radioactive alkali metal is mixed with particulate silica in a rotary drum reactor in which the alkali metal is converted to the monoxide during rotation of the reactor to produce particulate silica coated with the alkali metal monoxide suitable as a feed material to make a glass for storing radioactive material. Silica particles, the majority of which pass through a 95 mesh screen or preferably through a 200 mesh screen, are employed in this process, and the preferred weight ratio of silica to alkali metal is 7 to 1 in order to produce a feed material for the final glass product having a silica to alkali metal monoxide ratio of about 5 to 1

  2. Mining for metals in society's waste

    Science.gov (United States)

    Smith, Kathleen S.; Plumlee, Geoffrey S.; Hageman, Philip L.

    2015-01-01

    Metals are crucial to society and enable our modern standard of living. Look around and you can't help but see products made of metals. For instance, a typical gasoline-powered automobile contains over a ton of iron and steel, 240 pounds of aluminum, 42 pounds of copper, 41 pounds of silicon, 22 pounds of zinc and more than 30 other mineral commodities including titanium, platinum and gold.

  3. Anaerobic bioleaching of metals from waste activated sludge

    Energy Technology Data Exchange (ETDEWEB)

    Meulepas, Roel J.W., E-mail: roel.meulepas@wetsus.nl [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands); Gonzalez-Gil, Graciela [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands); King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Thuwal 13955-69000 (Saudi Arabia); Teshager, Fitfety Melese; Witharana, Ayoma [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands); Saikaly, Pascal E. [King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Thuwal 13955-69000 (Saudi Arabia); Lens, Piet N.L. [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands)

    2015-05-01

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether metals can be leached from waste activated sludge during the first, acidifying stage of two-stage anaerobic digestion without the supply of leaching agents. These leaching experiments were done with waste activated sludge from the Hoek van Holland municipal wastewater treatment plant (The Netherlands), which contained 342 μg g{sup −1} of copper, 487 μg g{sup −1} of lead, 793 μg g{sup −1} of zinc, 27 μg g{sup −1} of nickel and 2.3 μg g{sup −1} of cadmium. During the anaerobic acidification of 3 g{sub dry} {sub weight} L{sup −1} waste activated sludge, 80–85% of the copper, 66–69% of the lead, 87% of the zinc, 94–99% of the nickel and 73–83% of the cadmium were leached. The first stage of two-stage anaerobic digestion can thus be optimized as an anaerobic bioleaching process and produce a treated sludge (i.e., digestate) that meets the land-use standards in The Netherlands for copper, zinc, nickel and cadmium, but not for lead. - Highlights: • Heavy metals were leached during anaerobic acidification of waste activated sludge. • The process does not require the addition of chelating or oxidizing agents. • The metal leaching efficiencies (66 to 99%) were comparable to chemical leaching. • The produced leachate may be used for metal recovery and biogas production. • The produced digested sludge may be used as soil conditioner.

  4. Performance modeling of concrete/metal barriers used in low-level waste disposal

    International Nuclear Information System (INIS)

    Shuman, R.; Chau, Nam; Icenhour, A.S.; Godbee, H.W.; Tharp, M.L.

    1993-01-01

    Low-Level radioactive wastes generated in government and commercial operations involving nuclear materials need to be isolated from the environment almost in perpetuity. An increasing number of disposal sites are using concrete/metal barriers (so called ''engineered'' barriers) to isolate these wastes from the environment. Two major concerns hamper the use of engineered barriers; namely, the lack of ability to reliably predict the service life of these barriers and to estimate the confidence level of the service life predicted. Computer codes (SOURCE1 and SOURCE2) for estimating the long-term (centuries to millennia) service life of these barriers are presented. These codes use mathematical models (based on past observations, currently accepted data, and established theories) to predict behavior into the future. Processes modeled for concrete degradation include sulfate attack, calcium hydroxide leaching, and reinforcement corrosion. The loss of structural integrity due to cracking is also modeled. Mechanisms modeled for nuclide leaching include advection and diffusion. The coupled or linked effects of these models are addressed in the codes. Outputs from the codes are presented and analyzed

  5. Process for treating waste water having low concentrations of metallic contaminants

    Science.gov (United States)

    Looney, Brian B; Millings, Margaret R; Nichols, Ralph L; Payne, William L

    2014-12-16

    A process for treating waste water having a low level of metallic contaminants by reducing the toxicity level of metallic contaminants to an acceptable level and subsequently discharging the treated waste water into the environment without removing the treated contaminants.

  6. Electrochemical Corrosion Studies for Modeling Metallic Waste Form Release Rates

    Energy Technology Data Exchange (ETDEWEB)

    Poineau, Frederic [Univ. of Nevada, Las Vegas, NV (United States); Tamalis, Dimitri [Florida Memorial Univ., Miami Gardens, FL (United States)

    2016-08-01

    The isotope 99Tc is an important fission product generated from nuclear power production. Because of its long half-life (t1/2 = 2.13 ∙ 105 years) and beta-radiotoxicity (β⁻ = 292 keV), it is a major concern in the long-term management of spent nuclear fuel. In the spent nuclear fuel, Tc is present as an alloy with Mo, Ru, Rh, and Pd called the epsilon-phase, the relative amount of which increases with fuel burn-up. In some separation schemes for spent nuclear fuel, Tc would be separated from the spent fuel and disposed of in a durable waste form. Technetium waste forms under consideration include metallic alloys, oxide ceramics and borosilicate glass. In the development of a metallic waste form, after separation from the spent fuel, Tc would be converted to the metal, incorporated into an alloy and the resulting waste form stored in a repository. Metallic alloys under consideration include Tc–Zr alloys, Tc–stainless steel alloys and Tc–Inconel alloys (Inconel is an alloy of Ni, Cr and iron which is resistant to corrosion). To predict the long-term behavior of the metallic Tc waste form, understanding the corrosion properties of Tc metal and Tc alloys in various chemical environments is needed, but efforts to model the behavior of Tc metallic alloys are limited. One parameter that should also be considered in predicting the long-term behavior of the Tc waste form is the ingrowth of stable Ru that occurs from the radioactive decay of 99Tc (99Tc → 99Ru + β⁻). After a geological period of time, significant amounts of Ru will be present in the Tc and may affect its corrosion properties. Studying the effect of Ru on the corrosion behavior of Tc is also of importance. In this context, we studied the electrochemical behavior of Tc metal, Tc-Ni alloys (to model Tc-Inconel alloy) and Tc-Ru alloys in acidic media. The study of Tc-U alloys has also been performed in order to better understand the

  7. Impact Of Municipal Solid Waste On Trace Metal Concentrations In ...

    African Journals Online (AJOL)

    The impact of municipal solid waste on the levels of cadmium, copper, nickel, lead and zinc in herbage and soil samples within Abuja municipality was studied. The flame atomic absorption spectrophotometry was used in the determination of the metals. The average concentration of Cd, Cu, Ni, Pb and Zn in the herbage ...

  8. Melting of metallic intermediate level waste

    International Nuclear Information System (INIS)

    Huutoniemi, Tommi; Larsson, Arne; Blank, Eva

    2013-08-01

    This report presents a feasibility study of a melting facility for core components and reactor internals. An overview is given of how such a facility for treatment of intermediate level waste might be designed, constructed and operated and highlights both the possibilities and challenges. A cost estimate and a risk analysis are presented in order to make a conclusion of the technical feasibility of such a facility. Based on the authors' experience in operating a low level waste melting facility, their conclusion is that without technical improvements such a facility is not feasible today. This is based on the cost of constructing and operating such a facility, in conjunction with the radiological risks associated with operation and the uncertain benefits to disposal and long term safety

  9. Melting of metallic intermediate level waste

    Energy Technology Data Exchange (ETDEWEB)

    Huutoniemi, Tommi; Larsson, Arne; Blank, Eva [Studsvik Nuclear AB, Nykoeping (Sweden)

    2013-08-15

    This report presents a feasibility study of a melting facility for core components and reactor internals. An overview is given of how such a facility for treatment of intermediate level waste might be designed, constructed and operated and highlights both the possibilities and challenges. A cost estimate and a risk analysis are presented in order to make a conclusion of the technical feasibility of such a facility. Based on the authors' experience in operating a low level waste melting facility, their conclusion is that without technical improvements such a facility is not feasible today. This is based on the cost of constructing and operating such a facility, in conjunction with the radiological risks associated with operation and the uncertain benefits to disposal and long term safety.

  10. Heavy metals contamination of soils surrounding waste deposits in Romania

    Science.gov (United States)

    Matache, M.; Rozylowicz, L.; Ropota, M.; Patroescu, C.

    2003-05-01

    Soils contamination with heavy metals is one of the most severe aspects of environmental pollution in Romania, independently of the origin sources (domestic or industrial activities) or type of disposal (organised landfill or hazardous deposits)[l-2]. This fact is the consequence of the poor state of the existing waste deposits in Romania and of the significant costs involved by the establishing of a new landfill according with the international regulations. The present study is trying to emphasise the contamination of soils surrounding different categories of waste deposits (sewage sludge ponds, domestic and industrial waste landfills, hillocks, sterile deposits) from various regions of Romania. Some case studies show a special interest being localise in a protected area (Iron Gates Natural Park). In order to quantify the concentration of metals like Cd, Cr, Cu, Pb, Zn, Ni, Mo in soil samples, analysis were performed using Inductively Coupled Plasma - Optical Emission Spectrometry (ICP-OES). Romanian standards were used as reference values[3].

  11. Some thermal analysis aspects of metal encapsulated waste

    International Nuclear Information System (INIS)

    Jardine, L.J.; Steindler, M.J.

    1978-01-01

    This paper is to summarize two waste management schemes: (1) packaging for extended storage of LWR spent fuel assemblies, with the capability for simple conversion either to terminal storage if a ''throwaway'' fuel cycle is ultimately adopted or to a form that can be reprocessed and (2) packaging for the terminal storage of solidified high-level wastes when the reprocessing of spent fuel is initiated. Only concepts utilizing metals or metal alloys to encapsulate either spent fuel or solidified high-level waste forms have been considered. Conceptual process flow sheets have been constructed to allow potential advantages and disadvantages of encapsulation alternatives to be identified in comparison with more conventional reference processes. Identification is also made of uncertainties of the analysis due to a lack of fundamental data required to perform evaluations. 3 tables

  12. Oxidation behavior of Cr(III) during thermal treatment of chromium hydroxide in the presence of alkali and alkaline earth metal chlorides.

    Science.gov (United States)

    Mao, Linqiang; Gao, Bingying; Deng, Ning; Liu, Lu; Cui, Hao

    2016-02-01

    The oxidation behavior of Cr(III) during the thermal treatment of chromium hydroxide in the presence of alkali and alkaline earth metal chlorides (NaCl, KCl, MgCl2, and CaCl2) was investigated. The amounts of Cr(III) oxidized at various temperatures and heating times were determined, and the Cr-containing species in the residues were characterized. During the transformation of chromium hydroxide to Cr2O3 at 300 °C approximately 5% of the Cr(III) was oxidized to form intermediate compounds containing Cr(VI) (i.e., CrO3), but these intermediates were reduced to Cr2O3 when the temperature was above 400 °C. Alkali and alkaline earth metals significantly promoted the oxidation of Cr(III) during the thermal drying process. Two pathways were involved in the influences the alkali and alkaline earth metals had on the formation of Cr(VI). In pathway I, the alkali and alkaline earth metals were found to act as electron transfer agents and to interfere with the dehydration process, causing more intermediate Cr(VI)-containing compounds (which were identified as being CrO3 and Cr5O12) to be formed. The reduction of intermediate compounds to Cr2O3 was also found to be hindered in pathway I. In pathway II, the alkali and alkaline earth metals were found to contribute to the oxidation of Cr(III) to form chromates. The results showed that the presence of alkali and alkaline earth metals significantly increases the degree to which Cr(III) is oxidized during the thermal drying of chromium-containing sludge. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. On-site analysis of metals in waste oil

    International Nuclear Information System (INIS)

    Lambert, P.; Goldthorp, M.; Hollebone, B.P.

    2003-01-01

    TN Technologies has designed a field instrument which can rapidly detect up to 25 metals in soil, thin films or paint. The Spectrace 9000 XRF analyzer was also examined in a laboratory study to determine its capability in detecting and quantifying metals in waste oil. The oils selected for this experiment were: Alberta Sweet Mixed Blend crude, residual fuel oil No.5, a heavy fuel oil, Orimulsion, marine turbine oil 100, and a waste oil from a recent spill. These oils were tested under a variety of oil matrices. Results from the Spectrace 9000 were compared with those from a traditional laboratory technique based on inductively coupled plasma-atomic emission spectroscopy. The Spectrace 9000 proved capable of detecting a suite of metals in the oil. The best results were obtained when the manufacturer's soil application was applied and when analysis time exceeded 600 seconds. The long analysis time was compensated by the typically lower quantity of metals in oil compared to soil. In those cases where the concentration of the metal was in the vicinity of the instrument's lower detection limit, the probability of the instrument detecting and reporting a result for an individual metal was improved by replicate analysis. The results for the concentration values obtained with the Spectrace 9000 and laboratory analysis did not show numerical equivalency. At low concentrations, the results obtained with the XRF were double those obtained by the laboratory procedures. When the metal was present in significant quantities, the order of magnitude was even higher. 9 refs., 8 tabs

  14. Chemical stabilization of metals in mine wastes by transformed red mud and other iron compounds: laboratory tests.

    Science.gov (United States)

    Ardau, C; Lattanzi, P; Peretti, R; Zucca, A

    2014-01-01

    A series of static and kinetic laboratory-scale tests were designed in order to evaluate the efficacy of transformed red mud (TRM) from bauxite refining residues, commercial zero-valent iron, and synthetic iron (III) hydroxides as sorbents/reagents to minimize the generation of acid drainage and the release of toxic elements from multi-contaminant-laden mine wastes. In particular, in some column experiments the percolation of meteoric water through a waste pile, alternated with periods of dryness, was simulated. Wastes were placed in columns together with sorbents/reagents in three different set-ups: as blended amendment (mixing method), as a bed at the bottom of the column (filtration method), or as a combination of the two previous methods. The filtration methods, which simulate the creation of a permeable reactive barrier downstream of a waste pile, are the most effective, while the use of sorbents/reagents as amendments leads to unsatisfactory results, because of the selective removal of only some contaminants. The efficacy of the filtration method is not significantly affected by the periods of dryness, except for a temporary rise of metal contents in the leachates due to dissolution of soluble salts formed upon evaporation in the dry periods. These results offer original information on advantages/limits in the use of TRM for the treatment of multi-contaminant-laden mine wastes, and represent the starting point for experimentation at larger scale.

  15. Lixiviation of heavy metals of hazardous industrial wastes by means of thermostatized columns and design of a pilot plant

    International Nuclear Information System (INIS)

    Vite T, J.; Leon, C.C. de; Vite T, M.; Soto T, J.L.

    2006-01-01

    The purpose of this work was to evaluate the efficiency of lixiviation of heavy metals, using thermostatized columns and hazardous industrial residual wastes: those by the volume with which are generated and its high toxicity, its represent a great problem for it treatment and disposition, in this work a diagram of a pilot plant for extraction of heavy metals is included. The process and equipment were patented in United States and in Mexico. For the development of this study four thermostated columns were used that were coupled. The waste were finely milled and suspended in an aqueous pulp adding of 10 - 40gL -1 of mineral acid or sodium hydroxide until reaching an interval of pH of 2,5,7 and 10. Its were used of 4-10 gL -1 of a reducer agent and of 0.3-1.5 g of a surfactant agent. In some cases with this method was possible to remove until 100% of heavy metals. It was used Plasma Emission Spectroscopy to determine the concentrations of the cations in the lixiviation liquors. For studying the metallic alloys the X-ray diffraction technique was used. (Author)

  16. Anaerobic bioleaching of metals from waste activated sludge

    KAUST Repository

    Meulepas, Roel J W

    2015-05-01

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether metals can be leached from waste activated sludge during the first, acidifying stage of two-stage anaerobic digestion without the supply of leaching agents. These leaching experiments were done with waste activated sludge from the Hoek van Holland municipal wastewater treatment plant (The Netherlands), which contained 342μgg-1 of copper, 487μgg-1 of lead, 793μgg-1 of zinc, 27μgg-1 of nickel and 2.3μgg-1 of cadmium. During the anaerobic acidification of 3gdry weightL-1 waste activated sludge, 80-85% of the copper, 66-69% of the lead, 87% of the zinc, 94-99% of the nickel and 73-83% of the cadmium were leached. The first stage of two-stage anaerobic digestion can thus be optimized as an anaerobic bioleaching process and produce a treated sludge (i.e., digestate) that meets the land-use standards in The Netherlands for copper, zinc, nickel and cadmium, but not for lead.

  17. Adsorption of heavy metals in waste water using biological materials

    Directory of Open Access Journals (Sweden)

    Candelaria Tejada-Tovar

    2015-01-01

    Full Text Available Biosorption is a process that allows active or passive uptake of metal ions due to the property that different living or dead biomass have to bind and accumulate these pollutants by different mechanisms. The application of low-cost materials obtained from different biomass from microbial flora, agro-industrial waste and algae has been investigated to replace the use of conventional methods for the removal of contaminants such as heavy metals. Some of the metals of greatest impact to the environment due to its high toxicity and difficult to remove are chromium, nickel, cadmium, lead, and mercury. In this paper, an overview of adsorption as an alternative process for the removal of contaminants in solution and biomass commonly used in these processes, as well as some of the modifications made to improve the efficiency of adsorption of these materials is presented. It was concluded that the use of adsorption in the removal of pollutants in aqueous solution using waste biomass is applicable to these decontamination processes avoiding subsequent problems such as the generation of chemical sludge, and generating an alternative to use materials considered as waste. It is further identified that such factors as the pH of the solution, particle size, temperature, and concentration of metal effect on the process.

  18. Corrosion of metal containers containing cemented radioactive wastes

    International Nuclear Information System (INIS)

    Duffo, G.S.; Farina, S.B.; Schulz, F.M.; Marotta, F

    2010-01-01

    Nuclear activities generate different kinds of radioactive wastes. In the case of Argentina, wastes classified as low and medium level are conditioned in metal drums for final disposal in a repository whose design is based on the use of multiple and independent barriers. Nuclear energy plants generate a large volume of mid-level radioactive wastes, consisting mainly of ion-exchange resins contaminated by fission products. Other contaminated products such as gloves, papers, clothing, rubber and plastic tubing, can be incinerated and the ashes from the combustion also constitute wastes that must be disposed of. These wastes (resins and ashes) must be immobilized in order to avoid the release of radionuclides into the environment. The wastes usually undergo a process of cementing to immobilize them. This work aims to systematically study the process of degradation by corrosion of the steel drums in contact with the cemented resins and with the ashes cemented with the addition of different types and concentrations of aggressive compounds (chloride and sulfate). The specimens are configured so that the parameters of interest for the steel in contact with the cemented materials can be measured. The variables of corrosion potential, electric resistivity of the matrix and polarization resistance (PR) were monitored and show that the presence of chloride increases the susceptibility to corrosion of the drum steel that is in contact with the cement resin matrix

  19. Pollution prevention and waste minimization in metal finishing

    Energy Technology Data Exchange (ETDEWEB)

    Stimetz, C.J.

    1994-12-01

    This study was done to identify pollution prevention and waste minimization opportunities in the general plating department and the printed circuit board processing department. Recommendations for certain recycle and recovery technologies were mad in order to reduce usage of acids and the volume of heavy metal sludge that is formed at the industrial Wastewater Pretreatment Facility (IWPF). Some of these technologies discussed were acid purification, electrowinning, and ion exchange. Specific technologies are prescribed for specific processes. Those plating processes where the metals can be recovered are copper, nickel, gold, cadmium, tin, lead, and rhodium.

  20. Determination of Heavy Metal Levels in Various Industrial Waste Waters

    Directory of Open Access Journals (Sweden)

    Mustafa Şahin Dündar

    2012-06-01

    Full Text Available Important part of the environmetal pollution consists of waste water and water pollution. The water polluted by anthropogenical, industrial, and agricultural originated sources are defined as waste waters which are the main pollution sources for reservoirs, rivers, lakes, and seas. In this work, waste waters of leather, textile, automotive side, and metal plating industries were used to determine the levels of Cu, Zn, Cr, Pb and Ni by using Flame Atomic Absorption Spectrometer. As a result, highest mean levels of copper in supernatants of plating and textile industries were observed as 377,18 ng ml-1, respectively 103 ng ml-1 lead and 963,6 ng ml-1 nickel in plating industry, 1068,2 ng ml-1 zinc and 14557,1 ng ml-1 chromium in plating and leather industries were determined.

  1. Recycling of Metal Containing Waste by Liquid-Liquid Extraction

    International Nuclear Information System (INIS)

    Reinhardt, H.

    1999-01-01

    Through the years, a large number of liquid-liquid extraction have been proposed for metal waste recovery and recycling(1,2). However, few of them have achieved commercial application. In fact, relatively little information is available on practical operation and economic feasibility. This presentation will give complementary information by describing and comparing three processes, based on the Am MAR hydrometallurgical concept and representing three different modes of operation

  2. Heavy metal evaporation kinetics in thermal waste treatment processes

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, Ch.; Stucki, S.; Schuler, A.J. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    To investigate the evaporation kinetics of heavy metals, experiments were performed by conventional thermogravimetry and a new method using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). The new method allows online measurements in time intervals that are typically below one minute. The evaporation of Cd, Cu, Pb, and Zn from synthetic mixtures and filter ashes from municipal solid waste incineration (MSWI) was of major interest. (author) 2 figs., 4 refs.

  3. MINE WASTE TECHNOLOGY PROGRAM; PHOSPHATE STABILIZATION OF HEAVY METALS CONTAMINATED MINE WASTE YARD SOILS, JOPLIN, MISSOURI NPL SITE

    Science.gov (United States)

    This document summarizes the results of Mine Waste Technology Project 22-Phosphate Stabilization of Heavy Metals-Contaminated Mine Waste Yard Soils. Mining, milling, and smelting of ores near Joplin, Missouri, have resulted in heavy metal contamination of the area. The Joplin s...

  4. Metallic elements fractionation in municipal solid waste incineration residues

    Science.gov (United States)

    Kowalski, Piotr R.; Kasina, Monika; Michalik, Marek

    2016-04-01

    Municipal solid waste incineration (MSWI) residues are represented by three main materials: bottom ash, fly ash and air pollution control (APC) residues. Among them ˜80 wt% is bottom ash. All of that materials are products of high temperature (>1000° C) treatment of waste. Incineration process allows to obtain significant reduction of waste mass (up to 70%) and volume (up to 90%) what is commonly used in waste management to reduce the amount need to be landfilled or managed in other way. Incineration promote accumulation non-combustible fraction of waste, which part are metallic elements. That type of concentration is object of concerns about the incineration residues impact on the environment and also gives the possibility of attempts to recover them. Metallic elements are not equally distributed among the materials. Several factors influence the process: melting points, volatility and place and forms of metallic occurrence in the incinerated waste. To investigate metallic elements distribution in MSWI residues samples from one of the biggest MSW incineration plant in Poland were collected in 2015. Chemical analysis with emphasis on the metallic elements content were performed using inductively coupled plasma optical emission (ICP-OES) and mass spectrometry (ICP-MS). The bottom ash was a SiO2-CaO-Al2O3-Fe2O3-Na2O rich material, whereas fly ash and APC residues were mostly composed of CaO and SiO2. All of the materials were rich in amorphous phase occurring together with various, mostly silicate crystalline phases. In a mass of bottom ash 11 wt% were metallic elements but also in ashes 8.5 wt% (fly ash) and ˜4.5 wt% (APC residues) of them were present. Among the metallic elements equal distribution between bottom and fly ash was observed for Al (˜3.85 wt%), Mn (770 ppm) and Ni (˜65 ppm). In bottom ash Fe (5.5 wt%), Cr (590 ppm) and Cu (1250 ppm) were concentrated. These values in comparison to fly ash were 5-fold higher for Fe, 3-fold for Cu and 1.5-fold for

  5. Thermochemical treatment of radioactive waste by using powder metal fuels

    International Nuclear Information System (INIS)

    Dmitriev, S.A.; Ojovan, M.I.; Karlina, O.K.

    2001-01-01

    Full text: A thermochemical approach was suggested for treating and conditioning specific streams of radioactive wastes for example spent ion exchange resins, mixed, organic or chlorine-containing radioactive waste as well as in order to decontaminate heavily contaminated surfaces. Conventional treatment methods of such waste encounters serious problems concerning complete destruction of organic molecules and possible emissions of radionuclides, heavy metals and chemically hazardous species or in case of contaminated materials - complete removal of contamination from surface. The thermochemical treatment of radioactive waste uses powdered metal fuels (PMF) that are specifically formulated for the waste composition and react chemically with the waste components. Thermochemical treatment technologies use the energy of chemical reactions in the mixture of waste with PMF to sustain both decomposition and synthesis processes as well as processes of isomorphic substitutions of hazardous elements into stable mineral forms. The composition of the PMF is designed in such a way as to minimise the release of hazardous components and radionuclides in the off gas and to confine the contaminants in the mineral or glass like final products. The thermochemical procedures allow decomposition of organic matter and capturing hazardous radionuclides and chemical species simultaneously. Thermochemical treatment technologies are very efficient, easy to apply, they have low capital investment and can be used both at large and small facilities. An advantage of thermochemical technologies is their autonomy. Thus these technologies can be successfully applied in order to treat small amount of waste without usage of complex and expensive equipment. They can be used also in emergency situations. Currently the thermochemical treatment technologies were developed and demonstrated to be feasible as follows: 1. Decontamination of surfaces; 2. Processing of organic waste; 3. Vitrification of dusty

  6. Bacterial Treatment and Metal Characterization of Biomedical Waste Ash

    Directory of Open Access Journals (Sweden)

    Shelly Heera

    2014-01-01

    Full Text Available Biomedical waste ash generated due to the incineration of biomedical waste contains large amounts of heavy metals and polycyclic aromatic hydrocarbons (PAHs, which is disposed of in regular landfills, and results in unfavorable amounts of hazardous materials seeping into the ground and may pollute surface water and groundwater. Therefore, it is essential to remove the toxicity of ash before disposal into landfills or reutilization. Environmental characteristic analysis of BMW ash showed increased hardness (1320 mg/L and chloride (8500 mg/L content in leachate compared to World Health Organization (WHO and Environment Protection Agency (EPA guidelines for drinking water (hardness, 300 mg/L; chloride, 250 mg/L. The alkalinity and pH of the ash leachate were 400 mg/L and 8.35, respectively. In this paper, study was carried out to investigate the metal tolerance level of bacterial isolates isolated from soil. The isolate Bacillus sp. KGMDI can tolerate up to 75 mg/L of metal concentration (Mn, Mo, Cr, Fe, Cu, and Zn in enriched growth medium. This shows that the isolated culture is capable of growing in presence of high concentration of heavy metals and acts as potential biological tool to reduce the negative impact of BMW ash on the environment during landfilling.

  7. Waste or substrate for metal hyperaccumulating plants - The potential of phytomining on waste incineration bottom ash.

    Science.gov (United States)

    Rosenkranz, Theresa; Kisser, Johannes; Wenzel, Walter W; Puschenreiter, Markus

    2017-01-01

    Phytomining could represent an innovative low-cost technology for the selective recovery of valuable trace elements from secondary resources. In this context the potential of phytomining from waste incineration bottom ash was tested in a pot experiment. Fresh bottom ash was acidified, leached to reduce salinity and amended with organic material to obtain a suitable substrate for plant growth. Two hyperaccumulator species, Alyssum serpyllifolium subsp. lusitanicum and Sedum plumbizincicola as well as three metal tolerant species, Brassica napus, B. juncea and Nicotiana tabacum were tested for their phytomining potential on the pre-treated and amended bottom ashes from municipal solid waste and hazardous waste incineration. The hyperaccumulators had severe difficulties to establish on the bottom ash and to produce sufficient biomass, likely due to salinity and Cu toxicity. Nevertheless, concentrations of Ni in A. serpyllifolium and Zn in S. plumbizincicola were high, but total metal removal was limited by the low biomass production and was clearly less than on metalliferous soils. The Brassica species proved to be more tolerant to salinity and high Cu concentrations and produced considerably higher biomass, but total metal removal was limited by rather low shoot concentrations. The observed limitations of the phytomining process along with currently low market prices of Ni and Zn suggest that further optimisation of the process is required in order to make phytomining economically feasible on the tested waste incineration bottom ashes. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. The state of the art on the radioactive metal waste recycling technologies

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Won Jin; Moon, Jei Kwon; Jung, Chong Hun; Park, Sang Yoon

    1997-09-01

    As the best strategy to manage the radioactive metal wastes which are generated during operation and decommissioning of nuclear facilities, the following recycling technologies are investigated. 1. decontamination technologies for radioactive metal waste recycling 2. decontamination waste treatment technologies. 3. residual radioactivity evaluation technologies. (author). 260 refs., 26 tabs., 31 figs

  9. BIOACCUMULATION OF HEAVY METALS BY BACILLUS MEGATERIUM FROM PHOSPHOGYPSUM WASTE

    Directory of Open Access Journals (Sweden)

    IOANA ADRIANA STEFANESCU

    2015-05-01

    Full Text Available The aim of present study was to characterize the bioaccumulation capacity of heavy metals by Bacillus megaterium from phosphogypsum waste. The Bacillus megaterium strain (BM30 was isolated from soil near the phosphogypsum (PG dump. For the bioaccumulation quantification produced by BM30 strain were used three experimental treatments respectively with 2, 6 and 10 gL-1 PG. Cellular biomass samples were collected punctually at ages corresponding to the three stages of the development cycle of the microorganism: exponential phase, stationary phase and decline phase and the heavy metals concentrations were measured by atomic absorption spectroscopy. The bioaccumulation yields in cell biomass, relative to the total amount of analyte introduced in the reaction medium were between 20 - 80 %, the lowest value was recorded by Cu and highest by Mn. The study results indicated that the isolated strain near the dump PG, BM30, bioaccumulate heavy metals monitored in cell biomass in the order Cu > Fe > Zn = Mn.

  10. Effect of metal chlorides on thermal degradation of (waste) polycarbonate.

    Science.gov (United States)

    Chiu, Shwu-Jer; Chen, Shi-Hau; Tsai, Chou-Tso

    2006-01-01

    In this study, we investigated how to treat (waste) polycarbonate efficiently to reduce its degraded residue. The study was carried out in an isothermal reactor under continuous nitrogen flow at atmospheric pressure to pyrolyze polycarbonate (PC) alone and in the presence of metal chloride. Some metal chlorides were shown to be catalytic active for the degradation of PC at 400 degrees C, which increased degradation conversion from 8.5% to more than 58.3%. Among those active metal chlorides, ZnCl2 and SnCl2 can produce higher liquid product yields. Effects such as particle size of PC, temperature, the weight ratio of metal chloride/PC, and degradation time on the degradation conversion of PC without and with these two most active metal chlorides were studied. Results of the liquid product analysis by GC/MS demonstrated the product composition of PC degradation over the metal chlorides is much simpler than that of degradation alone. The main liquid product is phenol, p-isopropylphenol, diphenyl carbonate, and bisphenol A for all cases.

  11. BPEO/BPM in recycling of low level waste metal in the UK - 16210

    International Nuclear Information System (INIS)

    Dodd, Kevin; Robinson, Joe; Lindberg, Maria

    2009-01-01

    Best Practicable Environmental Option (BPEO) and Best Practicable Means (BPM) are concepts well established in the nuclear industry to help guide and inform waste management decision making. The recycling of contaminated metal waste in the UK is not well established, with the majority of waste disposed of at the Low Level Waste Repository (LLWR) at Drigg. This paper presents an overview of the Strategic BPEO study completed by Studsvik examining the options for low level metal waste management and a subsequent BPM study completed in support of a proposed metals recycling service. The environmental benefits of recycling metals overseas is further examined through the application of life cycle analysis to the metals recycling process. The methodologies used for both studies are discussed and the findings of these studies presented. These indicate that recycling contaminated metal is the preferred option, using overseas facilities until UK facilities are available. The BPM for metals recycling is discussed in detail and indicates that a tool box for processing metal waste is required to ensure BPM is applied on a case by case basis. This is supported by effective management of waste transport and waste acceptance criteria. Whilst the transport of contaminated metal overseas for treatment adds to the environmental burden of metals recycling, this when compared with the production of virgin metal, is shown to remain beneficial. The results of the Studsvik studies demonstrate the benefits of recycling metals, the options available for such a service and challenges that remain. (authors)

  12. TECHNOLOGY MATURATION PLAN FOR ALUMINUM REMOVAL AND SODIUM HYDROXIDE REGENERATION FROM HANFORD WASTE BY LITHIUM HYDROTALCITE PRECIPITATION

    Energy Technology Data Exchange (ETDEWEB)

    SAMS TL; GUILLOT S

    2011-01-27

    This Technology Maturation Plan schedules the development process that will bring the Lithium Hydrotalcite waste pretreatment process from its current estimated Technology Readiness Level of 3, to a level of 6. This maturation approach involves chemical and engineering research and development work, from laboratory scale to pilot scale testing, to incrementally make the process progress towards its integration in a fully qualified industrial system.

  13. Technology Maturation Plan For Aluminum Removal And Sodium Hydroxide Regeneration From Hanford Waste By Lithium Hydrotalcite Precipitation

    International Nuclear Information System (INIS)

    Sams, T.L.; Guillot, S.

    2011-01-01

    This Technology Maturation Plan schedules the development process that will bring the Lithium Hydrotalcite waste pretreatment process from its current estimated Technology Readiness Level of 3, to a level of 6. This maturation approach involves chemical and engineering research and development work, from laboratory scale to pilot scale testing, to incrementally make the process progress towards its integration in a fully qualified industrial system.

  14. Model description of the equivalent electroconductivity of aqueous solutions of alkali metal hydroxides over a wide range of concentrations and temperatures

    Science.gov (United States)

    Kuznetsova, E. M.; Volkov, D. S.

    2011-09-01

    The possibility of a quantitative theoretical description of the λ( c) dependence for aqueous solutions of alkali metal hydroxides in a wide concentration (from 0.0001 to 12 M) and temperature (from 0 to 100°C) was considered on the basis of concept suggested earlier. Effectiveness of the description of characteristics analyzed was illustrated on the examples of the calculation of electroconductivity values for aqueous LiOH, NaOH, KOH, RbOH, and CsOH solutions and comparison of them with experimental values taken from published data. The suggestion on different H+ and OH- ion migration mechanism was made on the basis of the model used for description of λ( c).

  15. Metallic elements occurrences within metallic fragments in the municipal waste incineration bottom ash

    Science.gov (United States)

    Kowalski, Piotr; Kasina, Monika; Michalik, Marek

    2017-04-01

    Bottom ash (BA) from municipal solid waste incineration (MSWI) is composed of grainy ash material, residual components and metallic fragments (from few µm up to 3-5 cm). Its mineral and chemical composition is related to the composition of the waste stream in the incinerator operational area. Wide use of thermal techniques in management of solid waste makes important the studies on valuable components and their distribution within the material in terms of their further processing. By using various valorization or extraction techniques it is possible to extend the range of its possible further application. To investigate metallic elements distribution within metallic fragments of the MSWI BA material produced in municipal waste incineration plant in Poland were collected in 2015 and 2016. BA and its components were investigated using spectroscopic methods of chemical analysis: ICP-OES, ICP-MS, LECO and EDS (used for microanalysis during SEM observations). BA is a material rich in Si (22.5 wt%), Ca (13.4 wt%), Fe (4 wt%), Al (5.2 wt%) and Na (3.5 wt%), composed of equal part of amorphous (silicate glass dominated) and crystalline phase (rich in silicates, aluminosilicates, oxides of non- and metallic elements and sulphates). The content of metallic elements (Al, Fe, Mg, Ti, Mn, Cr, Ni, Sc, Mo, Cu, Pb, Zn, Sn) is 11.5 wt% with domination of Al (5.2 wt%) and Fe (4 wt%) and elevated values of Mg (1 wt%), Ti (0.54 wt%), Cu (0.26 wt%) and Zn (0.27 wt%) (Kowalski et al., 2016). They were mostly concentrated in the form of metallic fragments, mainly as metallic inclusions in the size of 1-20 µm and separated metallic grains in the size of 50-300 µm. Metallic fragments present in the BA are characterized by their composition heterogeneity and various oxygen content. Fragments are rarely composed of single metallic element and usually in their composition up to few main elements dominated over others. The most common were Fe-, Al- and Zn-rich fragments forming respectively

  16. DOE mixed waste metals partition in a rotary kiln wet off-gas system

    International Nuclear Information System (INIS)

    Burns, D.B.; Looper, M.G.

    1994-01-01

    In 1996, the Savannah River Site plans to begin operation of the Consolidated Incineration Facility (CIF) to treat solid and liquid RCRA hazardous and mixed wastes. Test burns were conducted using surrogate CIF wastes spiked with hazardous metals and organics. The partition of metals between the kiln bottom ash, scrubber blowdown solution, and stack gas was measured as a function of kiln temperature, waste chloride content, and waste form (liquid or solid). Three waste simulants were used in these tests, a high and low chloride solid waste mix (paper, plastic, latex, PVC), and a liquid waste mix (benzene and chlorobenzene). An aqueous solution containing: antimony, arsenic, barium, cadmium, chromium, lead, mercury, nickel, silver, and thallium was added to the waste to determine metals fate under various combustion conditions. Test results were used to divide the metals into three general groups, volatile, semi-volatile, and nonvolatile metals. Mercury was the only volatile metal. No mercury remained in the kiln bottom ash under any incineration condition. Lead, cadmium, thallium, and silver exhibited semi-volatile behavior. The partition between the kiln ash, blowdown, and stack gas depended on incineration conditions. Chromium, nickel, barium, antimony, and arsenic exhibited nonvolatile behavior, with greater than 90 wt % of the metal remaining in the kiln bottom ash. Incineration temperature had a significant effect on the partition of volatile and semi-volatile metals, and no effect on nonvolatile metal partition. As incineration temperatures were increased, the fraction of metal leaving the kiln increased. Three metals, lead, cadmium, and mercury showed a relationship between chloride concentration in the waste and metals partition. Increasing the concentration of chlorides in the waste or burning liquid waste versus solid waste resulted in a larger fraction of metal exiting the kiln

  17. Resolving surface chemical states in XPS analysis of first row transition metals, oxides and hydroxides: Sc, Ti, V, Cu and Zn

    Science.gov (United States)

    Biesinger, Mark C.; Lau, Leo W. M.; Gerson, Andrea R.; Smart, Roger St. C.

    2010-11-01

    Chemical state X-ray photoelectron spectroscopic analysis of first row transition metals and their oxides and hydroxides is challenging due to the complexity of the 2p spectra resulting from peak asymmetries, complex multiplet splitting, shake-up and plasmon loss structure, and uncertain, overlapping binding energies. A review of current literature shows that all values necessary for reproducible, quantitative chemical state analysis are usually not provided. This paper reports a more consistent, practical and effective approach to curve-fitting the various chemical states in a variety of Sc, Ti, V, Cu and Zn metals, oxides and hydroxides. The curve-fitting procedures proposed are based on a combination of (1) standard spectra from quality reference samples, (2) a survey of appropriate literature databases and/or a compilation of the literature references, and (3) specific literature references where fitting procedures are available. Binding energies, full-width at half maximum (FWHM) values, spin-orbit splitting values, asymmetric peak-shape fitting parameters, and, for Cu and Zn, Auger parameters values are presented. The quantification procedure for Cu species details the use of the shake-up satellites for Cu(II)-containing compounds and the exact binding energies of the Cu(0) and Cu(I) peaks. The use of the modified Auger parameter for Cu and Zn species allows for corroborating evidence when there is uncertainty in the binding energy assignment. These procedures can remove uncertainties in analysis of surface states in nano-particles, corrosion, catalysis and surface-engineered materials.

  18. Two-Dimensional Layered Double Hydroxide Derived from Vermiculite Waste Water Supported Highly Dispersed Ni Nanoparticles for CO Methanation

    Directory of Open Access Journals (Sweden)

    Panpan Li

    2017-03-01

    Full Text Available Expanded multilayered vermiculite (VMT was successfully used as catalyst support and Ni/VMT synthesized by microwave irradiation assisted synthesis (MIAS exhibited excellent performance in our previous work. We also developed a two-dimensional porous SiO2 nanomesh (2D VMT-SiO2 by mixed-acid etching of VMT. Compared with three-dimensional (3D MCM-41, 2D VMT-SiO2 as a catalyst support provided a superior position for implantation of NiO species and the as-obtained catalyst exhibited excellent performance. In this paper, we successfully synthesized a layered double hydroxide (LDH using the spent liquor after mixed-acid etching of VMT, which mainly contained Mg2+ and Al3+. The as-calcined layered double oxide (LDO was used as a catalyst support for CO methanation. Compared with Ni/MgAl-LDO, Ni/VMT-LDO had smaller active component particles; therefore, in this study, it exhibited excellent catalytic performance over the whole temperature range of 250–500 °C. Ni/VMT-LDO achieved the best activity with 87.88% CO conversion, 89.97% CH4 selectivity, and 12.47 × 10−2·s−1 turn over frequency (TOF at 400 °C under a gas hourly space velocity of 20,000 mL/g/h. This study demonstrated that VMT-LDO as a catalyst support provided an efficient way to develop high-performance catalysts for synthetic natural gas (SNG from syngas.

  19. Thermal Analysis and Flame-Retarded Mechanism of Composites Composed of Ethylene Vinyl Acetate and Layered Double Hydroxides Containing Transition Metals (Mn, Co, Cu, Zn

    Directory of Open Access Journals (Sweden)

    Lili Wang

    2016-05-01

    Full Text Available The effects of transition metals on the hydrophobicity of nano–structured layered double hydroxides (LDHs and the compatibility of LDHs/ethylene vinyl acetate (EVA composites have seldom been reported. NiMgAl–LDHs slightly surface–modified with stearate and doped with transition metal cations (Mn2+, Co2+, Cu2+, Zn2+ are investigated. Compared to the pure EVA, not only were the maximal degradation–rate temperatures (Tmax of the ethylene–based chains enhanced, but also the smoke production rate (SPR and the production rate of CO (COP were sharply decreased for all the composites. Most importantly, a new flame retardant mechanism was found, namely the peak heat release rate (pk-HRR time, which directly depends on the peak production rate of CO2 (pk-CO2 time for EVA and all composites by cone calorimeter test. Moreover, the Mn–doped LDH S–NiMgAl–Mn shows more uniform dispersion and better interfacial compatibility in the EVA matrix. The cone calorimetric residue of S–NiMgAl–Mn/EVA has the intumescent char layer and the compact metal oxide layer. Therefore, S–NiMgAl–Mn/EVA shows the lowest pk-HRR and the longest pk-HRR time among all the composites.

  20. PHYTOREMEDIATION: A METHOD TO REDUCE METAL IONS PRESENT IN WASTE WATER

    OpenAIRE

    Shirin Imam*

    2017-01-01

    Heavy metal pollution is a worldwide concern; its severity and degree of pollution vary from place to place Metal contamination can be carried with soil particles get carried away from the original areas of pollution by wind and rain. The heavy metals which are mostly found in mining waste include arsenic, cadmium, chromium, copper, lead, nickel, and zinc, all of which cause risks for human health and the environment. Industrial waste water also adds to this problem. When waste water comes in...

  1. Continuous Process for Biodiesel Production in Packed Bed Reactor from Waste Frying Oil Using Potassium Hydroxide Supported on Jatropha curcas Fruit Shell as Solid Catalyst

    Directory of Open Access Journals (Sweden)

    Achanai Buasri

    2012-08-01

    Full Text Available The transesterification of waste frying oil (WFO with methanol in the presence of potassium hydroxide catalyst supported on Jatropha curcas fruit shell activated carbon (KOH/JS was studied. The catalyst systems were characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM and the Brunauer–Emmett–Teller (BET method. The effects of reaction variables such as residence time, reaction temperature, methanol/oil molar ratio and catalyst bed height in packed bed reactor (PBR on the yield of biodiesel were investigated. SEM images showed that KOH was well distributed on the catalyst support. The optimum conditions for achieving the conversion yield of 86.7% consisted of a residence time of 2 h, reaction temperature of 60 °C, methanol/oil molar ratio of 16 and catalyst bed height of 250 mm. KOH/JS could be used repeatedly five times without any activation treatment, and no significant activity loss was observed. The results confirmed that KOH/JS catalyst had a great potential to be used for industrial application in the transesterification of WFO. The fuel properties of biodiesel were also determined.

  2. Reprocessing of radioactive waste, toward recycling of nuclear rare metals

    International Nuclear Information System (INIS)

    Ozawa, M.

    2010-01-01

    Conclusions: Rare metals are inevitable in the leading industries and hold the national GDP. Industry-oriented, light PGM and Ln, etc, are localized and must be exhausted. They will become “strategic material”like oils by producing countries. Nuclear fission reaction will create 31 rare metals as well as energy. Now, SF should be considered as nota waste but a new artificial ore.In the flame of Adv.-ORIENT Cycle research, hydrometallurgical, soft and salt-free, separation processes are under developing. A hybrid system of CEE and IXC, in HNO3/HCl media with CH3OH, is promising in separation chemistry. Radio-toxicity of eventually vitrified HLLW is expected to be significantly decreased. To increase the reality, active tests on the separation system are planed in this year. Investigation on engineering issue, safety and costs will be the key

  3. Hydrometallurgical Recovery of Precious Metals and Removal of Hazardous Metals Using Persimmon Tannin and Persimmon Wastes

    Directory of Open Access Journals (Sweden)

    Katsutoshi Inoue

    2015-10-01

    Full Text Available Novel and environmentally benign adsorbents were prepared via a simple sulfuric acid treatment process using the wastes of astringent persimmon, a type of biomass waste, along with persimmon tannin extract which is currently employed for the tanning of leather and as natural dyes and paints. The effectiveness of these new biosorbents was exemplified with regards to hydrometallurgical and environmental engineering applications for the adsorptive removal of uranium and thorium from rare earths, cesium from other alkaline metals such as sodium, hexa-valent chromium from zinc as well as adsorptive recovery of gold from chloride media. Furthermore, reductive coagulation of gold from chloride media for the direct recovery of metallic gold and adsorptive recovery of palladium and platinum using chemically modified persimmon tannin extract were studied. OPEN

  4. Improvement to a production process of rare earth hydroxide by treatment of ores containing rare earth phosphates

    International Nuclear Information System (INIS)

    Fabre, F.; Lambert, A.; Tognet, J.P.

    1987-01-01

    Ore is treated by an aqueous solution of alkaline metal hydroxide and solid rare earth hydroxides are separated. For recycling the alkaline hydroxide after concentration the alkaline metal phosphate is crystallized and then alkaline earth metal hydroxide is added to avoid silicates concentration in the recycled solution [fr

  5. Enhanced selective metal adsorption on optimised agroforestry waste mixtures.

    Science.gov (United States)

    Rosales, Emilio; Ferreira, Laura; Sanromán, M Ángeles; Tavares, Teresa; Pazos, Marta

    2015-04-01

    The aim of this work is to ascertain the potentials of different agroforestry wastes to be used as biosorbents in the removal of a mixture of heavy metals. Fern (FE), rice husk (RI) and oak leaves (OA) presented the best removal percentages for Cu(II) and Ni(II), Mn(II) and Zn(II) and Cr(VI), respectively. The performance of a mixture of these three biosorbents was evaluated, and an improvement of 10% in the overall removal was obtained (19.25mg/g). The optimum mixture proportions were determined using simplex-centroid mixture design method (FE:OA:RI=50:13.7:36.3). The adsorption kinetics and isotherms of the optimised mixture were fit by the pseudo-first order kinetic model and Langmuir isotherm. The adsorption mechanism was studied, and the effects of the carboxylic, hydroxyl and phenolic groups on metal-biomass binding were demonstrated. Finally, the recoveries of the metals using biomass were investigated, and cationic metal recoveries of 100% were achieved when acidic solutions were used. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Assessment of toxic metals in waste personal computers.

    Science.gov (United States)

    Kolias, Konstantinos; Hahladakis, John N; Gidarakos, Evangelos

    2014-08-01

    Considering the enormous production of waste personal computers nowadays, it is obvious that the study of their composition is necessary in order to regulate their management and prevent any environmental contamination caused by their inappropriate disposal. This study aimed at determining the toxic metals content of motherboards (printed circuit boards), monitor glass and monitor plastic housing of two Cathode Ray Tube (CRT) monitors, three Liquid Crystal Display (LCD) monitors, one LCD touch screen monitor and six motherboards, all of which were discarded. In addition, concentrations of chromium (Cr), cadmium (Cd), lead (Pb) and mercury (Hg) were compared with the respective limits set by the RoHS 2002/95/EC Directive, that was recently renewed by the 2012/19/EU recast, in order to verify manufacturers' compliance with the regulation. The research included disassembly, pulverization, digestion and chemical analyses of all the aforementioned devices. The toxic metals content of all samples was determined using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The results demonstrated that concentrations of Pb in motherboards and funnel glass of devices with release dates before 2006, that is when the RoHS Directive came into force, exceeded the permissible limit. In general, except from Pb, higher metal concentrations were detected in motherboards in comparison with plastic housing and glass samples. Finally, the results of this work were encouraging, since concentrations of metals referred in the RoHS Directive were found in lower levels than the legislative limits. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Method of disposing radioactive wastes

    International Nuclear Information System (INIS)

    Isozaki, Kei.

    1983-01-01

    Purpose : To enable safety ocean disposal of radioactive wastes by decreasing the leaching rate of radioactive nucleides, improving the quick-curing nature and increasing the durability. Method : A mixture comprising 2 - 20 parts by weight of alkali metal hydroxide and 100 parts by weight of finely powdered aqueous slags from a blast furnace is added to radioactive wastes to solidify them. In the case of medium or low level radioactive wastes, the solidification agent is added by 200 parts by weight to 100 parts by weight of the wastes and, in the case of high level wastes, the solidification agent is added in such an amount that the wastes occupy about 20% by weight in the total of the wastes and the solidification agent. Sodium hydroxide used as the alkali metal hydroxide is partially replaced with sodium carbonate, a water-reducing agent such as lignin sulfonate is added to improve the fluidity and suppress the leaching rate and the wastes are solidified in a drum can. In this way, corrosions of the vessel can be suppressed by the alkaline nature and the compression strength, heat stability and the like of the product also become excellent. (Sekiya, K.)

  8. Comparative assessment of metallurgical recovery of metals from electronic waste with special emphasis on bioleaching.

    Science.gov (United States)

    Priya, Anshu; Hait, Subrata

    2017-03-01

    Waste electrical and electronic equipment (WEEE) or electronic waste (e-waste) is one of the fastest growing waste streams in the urban environment worldwide. The core component of printed circuit board (PCB) in e-waste contains a complex array of metals in rich quantity, some of which are toxic to the environment and all of which are valuable resources. Therefore, the recycling of e-waste is an important aspect not only from the point of waste treatment but also from the recovery of metals for economic growth. Conventional approaches for recovery of metals from e-waste, viz. pyrometallurgical and hydrometallurgical techniques, are rapid and efficient, but cause secondary pollution and economically unviable. Limitations of the conventional techniques have led to a shift towards biometallurgical technique involving microbiological leaching of metals from e-waste in eco-friendly manner. However, optimization of certain biotic and abiotic factors such as microbial species, pH, temperature, nutrients, and aeration rate affect the bioleaching process and can lead to profitable recovery of metals from e-waste. The present review provides a comprehensive assessment on the metallurgical techniques for recovery of metals from e-waste with special emphasis on bioleaching process and the associated factors.

  9. Option managing for radioactive metallic waste from the decommissioning of Kori Unit 1

    Energy Technology Data Exchange (ETDEWEB)

    Kessel, David S.; Kim, Chagn Lak [KEPCO International Nuclear Graduate School (KINGS), Ulsan (Korea, Republic of)

    2017-06-15

    The purpose of this paper is to evaluate several leading options for the management of radioactive metallic waste against a set of general criteria including safety, cost effectiveness, radiological dose to workers and volume reduction. Several options for managing metallic waste generated from decommissioning are evaluated in this paper. These options include free release, controlled reuse, and direct disposal of radioactive metallic waste. Each of these options may involve treatment of the metal waste for volume reduction by physical cutting or melting. A multi-criteria decision analysis was performed using the Analytic Hierarchy Process (AHP) to rank the options. Melting radioactive metallic waste to produce metal ingots with controlled reuse or free release is found to be the most effective option.

  10. Sorption of trace amounts of 67Ga and 65Zn on some divalent and trivalent metal hydroxides

    International Nuclear Information System (INIS)

    Music, S.; Sipalo-Zuljevic, J.; Vlatkovic, M.

    1977-01-01

    Trace concentrations of 67 Ga and 65 Zn were applied to the radiochemical study of sorption using Al(III), Cr(III), Fe(III), In(III), La(III), Zn(II), Cu(II) and Ni(II) hydroxides as sorbents. The results are given in terms of percentages sorbed, depending on solution pH or on the time of contact between the heterofeneous phases. The percentage sorbed is strongly pH-dependent. Sorption curves for 67 Ga show the maximum sorption (about 100%) starting from the pH values at the onset of the sorbent precipitation and ending with their approximate isoelectric point. Further increase in pH leads to a sudden decrease of the amounts sorbed. The sorption of 65 Zn is also pH-dependent; the decrease of sorption proceeds from right-to-left on the pH scale, i.e. in reverse direction if compared with gallium. The results are explained in terms of coprecipitation, electrostatic attraction (repulsion) and Van der Waals induced dipole attraction. Some sorption results, concerning the contact time dependence of the sorption are discussed in terms of specific sorption controlled by the diffusion of sorbate into the solid sorbent. (author)

  11. Biotechnology in the management and resource recovery from metal bearing solid wastes: Recent advances.

    Science.gov (United States)

    Sethurajan, Manivannan; van Hullebusch, Eric D; Nancharaiah, Yarlagadda V

    2018-04-01

    Solid metalliferous wastes (sludges, dusts, residues, slags, red mud and tailing wastes) originating from ferrous and non-ferrous metallurgical industries are a serious environmental threat, when waste management practices are not properly followed. Metalliferous wastes generated by metallurgical industries are promising resources for biotechnological extraction of metals. These wastes still contain significant amounts of valuable non-ferrous metals, sometimes precious metals and also rare earth elements. Elemental composition and mineralogy of the metallurgical wastes is dependent on the nature of mining site and composition of primary ores mined. Most of the metalliferous wastes are oxidized in nature and contain less/no reduced sulfidic minerals (which can be quite well processed by biohydrometallurgy). However, application of biohydrometallurgy is more challenging while extracting metals from metallurgical wastes that contain oxide minerals. In this review, origin, elemental composition and mineralogy of the metallurgical solid wastes are presented. Various bio-hydrometallurgical processes that can be considered for the extraction of non-ferrous metals from metal bearing solid wastes are reviewed. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Impact of informal electronic waste recycling on metal concentrations in soils and dusts.

    NARCIS (Netherlands)

    Ohajinwa, Chimere May; van Bodegom, Peter M; Vijver, Martina G; Peijnenburg, Willie J G M

    2018-01-01

    Electronic and electrical equipment contains over 1000 different substances, including metals. During informal e-waste recycling some of these substances such as metals, are released into the environment causing environmental pollution. This study assessed the impact of different informal e-waste

  13. Children with health impairments by heavy metals in an e-waste recycling area

    NARCIS (Netherlands)

    Zeng, Xiang; Xu, Xijin; Boezen, H. Marike; Huo, Xia

    E-waste recycling has become a global environmental health issue. Pernicious chemicals escape into the environment due to informal and nonstandard e-waste recycling activities involving manual dismantling, open burning to recover heavy metals and open dumping of residual fractions. Heavy metals

  14. Influence of potassium hydroxide activation on characteristics and environmental risk of heavy metals in chars derived from municipal sewage sludge.

    Science.gov (United States)

    Li, Zhengjia; Deng, Hui; Yang, Le; Zhang, Genlin; Li, Yuqi; Ren, Yansen

    2018-05-01

    To investigate the influence of KOH activation on characteristics and environmental risk of heavy metals in chars, sludge was pyrolyzed with varying amount of KOH. The analyzation of characteristics and potential ecological risk evaluation of heavy metals were conducted by surface area analyzer, FTIR, XRD and BCR sequential extraction. The activated chars have higher surface area and lower content of silica compared to those without being activated. The activation of KOH promoted residual fraction of Cd, meanwhile, Zinc, Cr, Ni and Mn were converted to relatively unstable fractions (F2 and F3). The results of risk assessment indicated that the potential ecological risk level of Cd was reduced in activated chars, while risk level of Zn, Cr, Ni and Mn were increased after pyrolysis with KOH activation. The potential ecological risk of heavy metals in activated chars was further declined, and the risk level transformed from moderate to low. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Characterization of potassium hydroxide (KOH) modified hydrochars from different feedstocks for enhanced removal of heavy metals from water.

    Science.gov (United States)

    Sun, Kejing; Tang, Jingchun; Gong, Yanyan; Zhang, Hairong

    2015-11-01

    Hydrochars produced from different feedstocks (sawdust, wheat straw, and corn stalk) via hydrothermal carbonization (HTC) and KOH modification were used as alternative adsorbents for aqueous heavy metals remediation. The chemical and physical properties of the hydrochars and KOH-treated hydrochars were characterized, and the ability of hydrochars for removal of heavy metals from aqueous solutions as a function of reaction time, pH, and initial contaminant concentration was tested. The results showed that KOH modification of hydrochars might have increased the aromatic and oxygen-containing functional groups, such as carboxyl groups, resulting in about 2-3 times increase of cadmium sorption capacity (30.40-40.78 mg/g) compared to that of unmodified hydrochars (13.92-14.52 mg/g). The sorption ability among different feedstocks after modification was as the following: sawdust > wheat straw > corn stack. Cadmium sorption kinetics on modified hydrochars could be interpreted with a pseudo-second order, and sorption isotherm was simulated with Langmuir adsorption model. High cadmium uptake on modified hydrochars was observed over the pH range of 4.0-8.0, while for other heavy metals (Pb(2+), Cu(2+), and Zn(2+)) the range was 4.0-6.0. In a multi-metal system, the sorption capacity of heavy metals by modified hydrochars was also higher than that by unmodified ones and followed the order of Pb(II) > Cu(II) > Cd(II) > Zn(II). The results suggest that KOH-modified hydrochars can be used as a low cost, environmental-friendly, and effective adsorbent for heavy metal removal from aqueous solutions.

  16. Study of the leaching of heavy metals from waste water sludge and incinerator's ash, using coupled thermostated columns and DTPA as complex agent

    International Nuclear Information System (INIS)

    Vite T, J.; Vite T, M.; Guerrero D, J.; Carreno de Leon, M.C.

    2000-01-01

    We studied the metallic composition from waste water sludge and incinerators ashes of an incinerator located in Toluca, Mexico, the qualitative studies were made using the Activation Analysis technique, and fluorescence X-ray techniques. The quantitative analysis of heavy metals in the wastes were made using Inductively coupled plasma atomic emission spectrometry (Icp-Aes). For leaching the samples, we used four coupled thermostated columns, each one had a p H of 2,5, 7 and 10. The flux of the air was of 1600 cc/min. The temperature was maintain constant in 60 Centigrade using a thermostated system. For this study we used 100 g of wastes mixed with mineral acid or sodium hydroxide to reach p H 2,5,7 and 10. We added a reducing and tensoactive agents and finally DTPA as complex agent. With this method, we obtain a better leaching efficiency using a complex agent. However the high DTPA cost, make this process expansive that is why we recommend to work with another classes of complex agents, that be cheaper to leach metals of different chemistry matrix. (Author)

  17. Study of the migration of toxic metals in steelmaking waste using radioactive tracing

    International Nuclear Information System (INIS)

    Andre, C.; Jauzein, M.; Charentus, T.; Margrita, R.; Dechelette, O.

    1991-01-01

    The danger presented by toxic metals contained in steelmaking wastes put into slag piles may be neutralized by suitably chosen alternation of these wastes when they are deposited. Presentation of a study method using radioactive tracing of the migration of toxic metal (cadmium, zinc, chromium) in steelmaking wastes (slag, blast furnace sludge). This non destructive method was used in columns in the laboratory, but may be used in on-site slag piles [fr

  18. Treatment of radioactive metallic waste by the electro-slag melting method

    International Nuclear Information System (INIS)

    Ochiai, Atsuhiro; Nagura, Kanetake; Noura, Tsuyoshi

    1983-01-01

    The applicability of the electro-slag melting method for treating plutonuim contaminated metallic waste was studied. A 100kg test furnace was built and simulated metallic waste was melted and solidified in this furnace. Waste volume was reduced to 1/25 with a decontamination factor of 25 and the slag and the copper mold are repeatedly usable. The process is expected to be employed in the project of PWTF (Plutonium contaminated Wate Treatment Facilities). (author)

  19. Process and equipment qualification of the ceramic and metal waste forms for spent fuel treatment

    International Nuclear Information System (INIS)

    Marsden, Ken; Knight, Collin; Bateman, Kenneth; Westphal, Brian; Lind, Paul

    2005-01-01

    The electrometallurgical process for treating sodium-bonded spent metallic fuel at the Materials and Fuels Complex of the Idaho National Laboratory separates actinides and partitions fission products into two waste forms. The first is the metal waste form, which is primarily composed of stainless steel from the fuel cladding. This stainless steel is alloyed with 15w% zirconium to produce a very corrosion-resistant metal which binds noble metal fission products and residual actinides. The second is the ceramic waste form which stabilizes fission product-loaded chloride salts in a sodalite and glass composite. These two waste forms will be packaged together for disposal at the Yucca Mountain repository. Two production-scale metal waste furnaces have been constructed. The first is in a large argon-atmosphere glovebox and has been used for equipment qualification, process development, and process qualification - the demonstration of process reliability for production of the DOE-qualified metal waste form. The second furnace will be transferred into a hot cell for production of metal waste. Prototype production-scale ceramic waste equipment has been constructed or procured; some equipment has been qualified with fission product-loaded salt in the hot cell. Qualification of the remaining equipment with surrogate materials is underway. (author)

  20. Bio-processing of solid wastes and secondary resources for metal extraction – A review

    International Nuclear Information System (INIS)

    Lee, Jae-chun; Pandey, Banshi Dhar

    2012-01-01

    Highlights: ► Review focuses on bio-extraction of metals from solid wastes of industries and consumer goods. ► Bio-processing of certain effluents/wastewaters with metals is also included in brief. ► Quantity/composition of wastes are assessed, and microbes used and leaching conditions included. ► Bio-recovery using bacteria, fungi and archaea is highlighted for resource recycling. ► Process methodology/mechanism, R and D direction and scope of large scale use are briefly included. - Abstract: Metal containing wastes/byproducts of various industries, used consumer goods, and municipal waste are potential pollutants, if not treated properly. They may also be important secondary resources if processed in eco-friendly manner for secured supply of contained metals/materials. Bio-extraction of metals from such resources with microbes such as bacteria, fungi and archaea is being increasingly explored to meet the twin objectives of resource recycling and pollution mitigation. This review focuses on the bio-processing of solid wastes/byproducts of metallurgical and manufacturing industries, chemical/petrochemical plants, electroplating and tanning units, besides sewage sludge and fly ash of municipal incinerators, electronic wastes (e-wastes/PCBs), used batteries, etc. An assessment has been made to quantify the wastes generated and its compositions, microbes used, metal leaching efficiency etc. Processing of certain effluents and wastewaters comprising of metals is also included in brief. Future directions of research are highlighted.

  1. Leaching of gold, silver and accompanying metals from circuit boards (PCBs) waste

    OpenAIRE

    Jana Ficeriová; Peter Baláž; Eberhard Gock

    2011-01-01

    Au-Ag noble metal wastes represent a wide range of waste types and forms, with various accompanying metallic elements.The presented leaching strategy for Au-Ag contained in circuit boards (PCBs) aims at gaining gold and silver in the metallic form.Application of the proposed ammonium thiosulphate leaching process for the treatment of the above mentioned Au-Ag containing wastesrepresents a practical, economic and at the same time an ecological solution. The ammonium thiosulphate based leaching...

  2. Optimized Metal Recovery from Fly Ash from Municipal Solid Waste Incineration

    OpenAIRE

    Weibel, Gisela

    2017-01-01

    Switzerland plays a pioneering role in sustainable waste management with a long tradition of waste incineration and the prohibition to landfill unburnt municipal solid waste since 2000. In recent years, the focus has been laid on further reduction of pollutants from incineration residues because the revised Swiss Waste Ordinance prescribes the recovery of metals from fly ash starting in 2021. Fly ash collected in the heat recovery section and the electrostatic precipitator contains high conce...

  3. Engineering metal (hydr)oxide sorbents for removal of arsenate and similar weak-acid oxyanion contaminants: A critical review with emphasis on factors governing sorption processes.

    Science.gov (United States)

    Hristovski, Kiril D; Markovski, Jasmina

    2017-11-15

    To create an integrative foundation for engineering of the next generation inexpensive sorbent systems, this critical review addresses the existing knowledge gap in factor/performance relationships between weak-acid oxyanion contaminants and metal (hydr)oxide sorbents. In-depth understanding of fundamental thermodynamics and kinetics mechanisms, material fabrication, and analytical and characterization techniques, is necessary to engineer sorbent that exhibit high capacity, selectivity, stability, durability and mass transport of contaminants under a wide range of operating and water matrix conditions requirements. From the perspective of thermodynamics and kinetics, this critical review examines the factors affecting sorbent performances and analyzes the existing research to elucidate future directions aimed at developing novel sorbents for removal of weak-acid oxyanion contaminants from water. Only sorbents that allow construction of simple and inexpensive water treatment systems adapted to overcome fiscal and technological barriers burdening small communities could pave the road for providing inexpensive potable water to millions of people. Novel sorbents, which exhibit (1) poor performances in realistic operating and water matrix conditions and/or (2) do not comply with the purely driven economics factors of production scalability or cost expectations, are predestined to never be commercialized. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Lixiviation of heavy metals of hazardous industrial wastes by means of thermostatized columns and design of a pilot plant; Lixiviacion de metales pesados de residuos industriales peligrosos por medio de columnas termostatizadas y diseno de una planta piloto

    Energy Technology Data Exchange (ETDEWEB)

    Vite T, J.; Leon, C.C. de [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Vite T, M.; Soto T, J.L. [IPN, SEPI, ESIME 07738 Mexico D.F. (Mexico)]. e-mail: jvite@nuclear.inin.mx

    2006-07-01

    purpose of this work was to evaluate the efficiency of lixiviation of heavy metals, using thermostatized columns and hazardous industrial residual wastes: those by the volume with which are generated and its high toxicity, its represent a great problem for it treatment and disposition, in this work a diagram of a pilot plant for extraction of heavy metals is included. The process and equipment were patented in United States and in Mexico. For the development of this study four thermostated columns were used that were coupled. The waste were finely milled and suspended in an aqueous pulp adding of 10 - 40gL{sup -1} of mineral acid or sodium hydroxide until reaching an interval of pH of 2,5,7 and 10. Its were used of 4-10 gL{sup -1} of a reducer agent and of 0.3-1.5 g of a surfactant agent. In some cases with this method was possible to remove until 100% of heavy metals. It was used Plasma Emission Spectroscopy to determine the concentrations of the cations in the lixiviation liquors. For studying the metallic alloys the X-ray diffraction technique was used. (Author)

  5. Flow analysis of metals in a municipal solid waste management system.

    Science.gov (United States)

    Jung, C H; Matsuto, T; Tanaka, N

    2006-01-01

    This study aimed to identify the metal flow in a municipal solid waste (MSW) management system. Outputs of a resource recovery facility, refuse derived fuel (RDF) production facility, carbonization facility, plastics liquefaction facility, composting facility, and bio-gasification facility were analyzed for metal content and leaching concentration. In terms of metal content, bulky and incombustible waste had the highest values. Char from a carbonization facility, which treats household waste, had a higher metal content than MSW incinerator bottom ash. A leaching test revealed that Cd and Pb in char and Pb in RDF production residue exceeded the Japanese regulatory criteria for landfilling, so special attention should be paid to final disposal of these substances. By multiplying metal content and the generation rate of outputs, the metal content of input waste to each facility was estimated. For most metals except Cr, the total contribution ratio of paper/textile/plastics, bulky waste, and incombustible waste was over 80%. Approximately 30% of Cr originated from plastic packaging. Finally, several MSW management scenarios showed that most metals are transferred to landfills and the leaching potential of metals to the environment is quite small.

  6. Metal Recovery from Industrial Solid Waste — Contribution to Resource Sustainability

    Science.gov (United States)

    Yang, Yongxiang

    Increased demand of metals has driven the accelerated mining and metallurgical production in recent years, causing fast depletion of primary metals resources. On the contrary, the mining and metallurgical industry generates large amount of solid residues and waste such as tailings, slags, flue dust and leach residues, with relative low valuable metal contents. On the other hand, end-of-life (EoL) consumer products form another significant resources. The current technology and processes for primary metals production are not readily applicable for direct metals extraction from these waste materials, and special adaptation and tailor-made processes are required. In the present paper, various solid waste resources are reviewed, and current technologies and R&D trends are discussed. The recent research at author's group is illustrated for providing potential solutions to future resource problems, including metal recovery from MSW incinerator bottom ashes, zinc recovery from industrial ashes and residues, and rare earth metals recovery from EoL permanent magnets.

  7. Removal Process of Heavy Metal Ions from Squid Gut Wastes with Dilute Suluric Acid Leaching and Electrowinning Methods

    OpenAIRE

    嶋影, 和宜; 平井, 伸治; 戸田, 茂雄; 山本, 浩

    2003-01-01

    In order to remove heavy metal ions contained in organic squid gut waste, a novel process has been developed with both dilute suluric acid leaching and electrowinning methods. This process was consisted of three procedures, which are the elimination of greasy component in squid gut wastes, the dissolution of heavy metal ions and the electro-deposition of heavy metal ions. Heavy metal ions contained in organic squid gut wastes are zinc, cadmium and copper ions. Heavy metal ions are leached eas...

  8. Promotional effects of chemisorbed oxygen and hydroxide in the activation of C-H and O-H bonds over transition metal surfaces

    Science.gov (United States)

    Hibbitts, David; Neurock, Matthew

    2016-08-01

    Electronegative coadsorbates such as atomic oxygen (O*) and hydroxide (OH*) can act as Brønsted bases when bound to Group 11 as well as particular Group 8-10 metal surfaces and aid in the activation of X-H bonds. First-principle density functional theory calculations were carried out to systematically explore the reactivity of the C-H bonds of methane and surface methyl intermediates as well as the O-H bond of methanol directly and with the assistance of coadsorbed O* and OH* intermediates over Group 11 (Cu, Ag, and Au) and Group 8-10 transition metal (Ru, Rh, Pd, Os, Ir, and Pt) surfaces. C-H as well as O-H bond activation over the metal proceeds via a classic oxidative addition type mechanism involving the insertion of the metal center into the C-H or O-H bond. O* and OH* assist C-H and O-H activation over particular Group 11 and Group 8-10 metal surfaces via a σ-bond metathesis type mechanism involving the oxidative addition of the C-H or O-H bond to the metal along with a reductive deprotonation of the acidic C-H and O-H bond over the M-O* or M-OH* site pair. The O*- and OH*-assisted C-H activation paths are energetically preferred over the direct metal catalyzed C-H scission for all Group 11 metals (Cu, Ag, and Au) with barriers that are 0.4-1.5 eV lower than those for the unassisted routes. The barriers for O*- and OH*-assisted C-H activation of CH4 on the Group 8-10 transition metals, however, are higher than those over the bare transition metal surfaces by as much as 1.4 eV. The C-H activation of adsorbed methyl species show very similar trends to those for CH4 despite the differences in structure between the weakly bound methane and the covalently adsorbed methyl intermediates. The activation of the O-H bond of methanol is significantly promoted by O* as well as OH* intermediates over both the Group 11 metals (Cu, Ag, and Au) as well as on all Group 8-10 metals studied (Ru, Rh, Pd, Os, Ir, and Pt). The O*- and OH*-assisted CH3O-H barriers are 0.6 to 2

  9. Leaching characteristics of the metal waste form from the electrometallurgical treatment process: Product consistency testing

    International Nuclear Information System (INIS)

    Johnson, S. G.; Keiser, D. D.; Frank, S. M.; DiSanto, T.; Noy, M.

    1999-01-01

    Argonne National Laboratory is developing an electrometallurgical treatment for spent fuel from the experimental breeder reactor II. A product of this treatment process is a metal waste form that incorporates the stainless steel cladding hulls, zirconium from the fuel and the fission products that are noble to the process, i.e., Tc, Ru, Nb, Pd, Rh, Ag. The nominal composition of this waste form is stainless steel/15 wt% zirconium/1--4 wt% noble metal fission products/1--2 wt % U. Leaching results are presented from several tests and sample types: (1) 2 week monolithic immersion tests on actual metal waste forms produced from irradiated cladding hulls, (2) long term (>2 years) pulsed flow tests on samples containing technetium and uranium and (3) crushed sample immersion tests on cold simulated metal waste form samples. The test results will be compared and their relevance for waste form product consistency testing discussed

  10. THE INFLUENCE OF SELECTED FACTORS ON THE LEACHING OF HEAVY METALS FROM SMELTER WASTE

    Directory of Open Access Journals (Sweden)

    Kamila Mizerna

    2015-07-01

    Full Text Available The paper presents the results of leaching research of selected heavy metals (Pb, Cu, Zn, Ni, Cd, Cr from industrial waste. The impact of waste fragmentation on the level of heavy metals leaching was analyzed. The decrease of copper and zinc release and the increase of nickel leaching were observed with increasing grain size fraction of waste. Furthermore, release of contaminants in different ratio of liquid to solid (L/S = 10 dm3/kg and 2 dm3/kg was studied. Higher concentrations of heavy metals were determined in ratio of L/S = 10 dm3/kg. In order to determine the risk of tested waste to the environment, the results were compared with the current law. This allowed the classification of the waste to hazardous waste.

  11. The effect of waste water treatment on river metal concentrations: removal or enrichment?

    NARCIS (Netherlands)

    Teuchies, J.; Bervoets, L.; Cox, T.J.S.; Meire, P.; de Deckere, E.

    2011-01-01

    Purpose Discharge of untreated domestic and industrial waste in many European rivers resulted in low oxygen concentrations and contamination with trace metals, often concentrated in sediments. Under these anoxic conditions, the formation of insoluble metal sulfides is known to reduce metal

  12. Analysis of the application of decontamination technologies to radioactive metal waste minimization using expert systems

    International Nuclear Information System (INIS)

    Bayrakal, S.

    1993-01-01

    Radioactive metal waste makes up a significant portion of the waste currently being sent for disposal. Recovery of this metal as a valuable resource is possible through the use of decontamination technologies. Through the development and use of expert systems a comparison can be made of laser decontamination, a technology currently under development at Ames Laboratory, with currently available decontamination technologies for applicability to the types of metal waste being generated and the effectiveness of these versus simply disposing of the waste. These technologies can be technically and economically evaluated by the use of expert systems techniques to provide a waste management decision making tool that generates, given an identified metal waste, waste management recommendations. The user enters waste characteristic information as input and the system then recommends decontamination technologies, determines residual contamination levels and possible waste management strategies, carries out a cost analysis and then ranks, according to cost, the possibilities for management of the waste. The expert system was developed using information from literature and personnel experienced in the use of decontamination technologies and requires validation by human experts and assignment of confidence factors to the knowledge represented within

  13. Analysis of the application of decontamination technologies to radioactive metal waste minimization using expert systems

    Energy Technology Data Exchange (ETDEWEB)

    Bayrakal, Suna [Iowa State Univ., Ames, IA (United States)

    1993-09-30

    Radioactive metal waste makes up a significant portion of the waste currently being sent for disposal. Recovery of this metal as a valuable resource is possible through the use of decontamination technologies. Through the development and use of expert systems a comparison can be made of laser decontamination, a technology currently under development at Ames Laboratory, with currently available decontamination technologies for applicability to the types of metal waste being generated and the effectiveness of these versus simply disposing of the waste. These technologies can be technically and economically evaluated by the use of expert systems techniques to provide a waste management decision making tool that generates, given an identified metal waste, waste management recommendations. The user enters waste characteristic information as input and the system then recommends decontamination technologies, determines residual contamination levels and possible waste management strategies, carries out a cost analysis and then ranks, according to cost, the possibilities for management of the waste. The expert system was developed using information from literature and personnel experienced in the use of decontamination technologies and requires validation by human experts and assignment of confidence factors to the knowledge represented within.

  14. Recovery of metals and nonmetals from electronic waste by physical and chemical recycling processes.

    Science.gov (United States)

    Kaya, Muammer

    2016-11-01

    This paper reviews the existing and state of art knowledge for electronic waste (e-waste) recycling. Electrical and/or electronic devices which are unwanted, broken or discarded by their original users are known as e-waste. The main purpose of this article is to provide a comprehensive review of e-waste problem, strategies of e-waste management and various physical, chemical and metallurgical e-waste recycling processes, their advantages and disadvantages towards achieving a cleaner process of waste utilization, with special attention towards extraction of both metallic values and nonmetallic substances. The hazards arise from the presence of heavy metals Hg, Cd, Pb, etc., brominated flame retardants (BFRs) and other potentially harmful substances in e-waste. Due to the presence of these substances, e-waste is generally considered as hazardous waste and, if improperly managed, may pose significant human and environmental health risks. This review describes the potential hazards and economic opportunities of e-waste. Firstly, an overview of e-waste/printed circuit board (PCB) components is given. Current status and future perspectives of e-waste/PCB recycling are described. E-waste characterization, dismantling methods, liberation and classification processes are also covered. Manual selective dismantling after desoldering and metal-nonmetal liberation at -150μm with two step crushing are seen to be the best techniques. After size reduction, mainly physical separation processes employing gravity, electrostatic, magnetic separators, froth floatation, etc. have been critically reviewed here for separation of metals and nonmetals, along with useful utilizations of the nonmetallic materials. The recovery of metals from e-waste material after physical separation through pyrometallurgical, hydrometallurgical or biohydrometallurgical routes is also discussed along with purification and refining. Suitable PCB recycling flowsheets for industrial applications are also given

  15. Sodium hydroxide poisoning

    Science.gov (United States)

    Sodium hydroxide is a very strong chemical. It is also known as lye and caustic soda. This ... poisoning from touching, breathing in (inhaling), or swallowing sodium hydroxide. This article is for information only. Do ...

  16. Evaluation of heavy metals in the process of composting organic waste of coca leaves

    Directory of Open Access Journals (Sweden)

    Apaza-Condori Emma Eva

    2015-11-01

    Full Text Available The present study is to evaluate the total concentrations of the heavy metals in waste compost samples from coca leaf. This work was carried out Kallutaca Experimental Center, Biofertilizers module Career Agricultural Engineering at the Public University of El Alto, La Paz municipality of Laja. Posed treatments were: T1 (+ Yogurt Coca wastes; T2 (Coca wastes + whey; T3 (Coca wastes + yeast and T4 (Control. The design was completely randomized with 4 treatments and 3 repetitions. The concentration of heavy metals (cadmium, copper, nickel, lead, mercury and chromium; they were categorized into Class A, for the four treatments according to the classifications established by Moreno & Moral (2008.

  17. Development of technique for quantifying gamma emitters in metal waste. New technique of precise and automatic measurements for confirmation of clearance level of metal waste

    International Nuclear Information System (INIS)

    Hattori, Takatoshi

    2002-01-01

    A New technique of precise and automatic measurements of gamma emitters in metal waste has been developed using 3D non-contact shape measurement and monte-carlo calculation techniques in order to confirm that specific radioactivity level of metal waste satisfies the clearance level and furthermore the surface contamination level of the metal waste is below the legal standard level. The technique can give a calibration factor every measurement target automatically and realize an automatic correction for reduction of background count rate in gamma measurements due to self-shield effect of the measurement target. The accuracy of the present method has been made clear using mock-metal wastes with various types of shape, number and size. Assuming the goal of the detection limit for practical use is 25OBq in radioactivity, a concept of the practical gamma monitor has been designed so as to be able to confirm both the clearance level and surface contamination level simultaneously and to cope with the metal waste at a speed of 2-10 ton a day. (author)

  18. Lead ion adsorption on montmorillonite-Al hydroxide polymer systems

    NARCIS (Netherlands)

    Janssen, R.P.T.; Bruggenwert, M.G.M.; Dijk, van G.; Riemsdijk, van W.H.

    2007-01-01

    Clay¿Al hydroxide polymer systems (CAlHO) can bind heavy metals effectively. Their adsorption behaviour depends on the type of metal. We studied the dependence of Al-loading and pH on the adsorption of Pb to Na-saturated montmorillonite¿Al hydroxide polymer systems. The available binding sites on

  19. Zinc ion adsorption on montmorillonite-Al hydroxide polymer systems

    NARCIS (Netherlands)

    Janssen, R.P.T.; Bruggenwert, M.G.M.; Riemsdijk, van W.H.

    2003-01-01

    Clay¿Al hydroxide polymers (CAlHO) can bind heavy metals effectively and may play an important role in the adsorption behaviour and metal binding capacity of soils. We studied the dependence of Al loading and pH on the adsorption of Zn on Na-saturated montmorillonite¿Al hydroxide polymer systems.

  20. Characterizing the environmental impact of metals in construction and demolition waste.

    Science.gov (United States)

    Yu, Danfeng; Duan, Huabo; Song, Qingbin; Li, Xiaoyue; Zhang, Hao; Zhang, Hui; Liu, Yicheng; Shen, Weijun; Wang, Jinben

    2018-03-06

    Large quantities of construction and demolition (C&D) waste are generated in China every year, but their potential environmental impacts on the surrounding areas are rarely assessed. This study focuses on metals contained in C&D waste, characterizing the metal concentrations and their related environmental risks. C&D waste samples were collected in Shenzhen City, China, from building demolition sites, renovation areas undergoing refurbishment, landfill sites, and recycling companies (all located in Shenzhen city) that produce recycled aggregate, in order to identify pollution levels of the metals As, Cd, Cr, Cu, Pb, Ni, and Zn. The results showed that (1) the metal concentrations in most demolition and renovation waste samples were below the soil environmental quality standard for agricultural purposes (SQ-Agr.) in China; (2) Cd, Cu, and Zn led to relatively higher environmental risks than other metals, especially for Zn (DM5 tile sample, 360 mg/kg; R4 tile sample, 281 mg/kg); (3) non-inert C&D waste such as wall insulation and foamed plastic had high concentrations of As and Cd, so that these materials required special attention for sound waste management; and (4) C&D waste collected from landfill sites had higher concentrations of Cd and Cu than did waste collected from demolition and refurbishment sites.

  1. Metal Extraction Processes for Electronic Waste and Existing Industrial Routes: A Review and Australian Perspective

    Directory of Open Access Journals (Sweden)

    Abdul Khaliq

    2014-02-01

    Full Text Available The useful life of electrical and electronic equipment (EEE has been shortened as a consequence of the advancement in technology and change in consumer patterns. This has resulted in the generation of large quantities of electronic waste (e-waste that needs to be managed. The handling of e-waste including combustion in incinerators, disposing in landfill or exporting overseas is no longer permitted due to environmental pollution and global legislations. Additionally, the presence of precious metals (PMs makes e-waste recycling attractive economically. In this paper, current metallurgical processes for the extraction of metals from e-waste, including existing industrial routes, are reviewed. In the first part of this paper, the definition, composition and classifications of e-wastes are described. In the second part, separation of metals from e-waste using mechanical processing, hydrometallurgical and pyrometallurgical routes are critically analyzed. Pyrometallurgical routes are comparatively economical and eco-efficient if the hazardous emissions are controlled. Currently, pyrometallurgical routes are used initially for the segregation and upgrading of PMs (gold and silver into base metals (BMs (copper, lead and nickel and followed by hydrometallurgical and electrometallurgical processing for the recovery of pure base and PMs. For the recycling of e-waste in Australia, challenges such as collection, transportation, liberation of metal fractions, and installation of integrated smelting and refining facilities are identified.

  2. Review of metal-matrix encapsulation of solidified radioactive high-level waste

    International Nuclear Information System (INIS)

    Jardine, L.J.; Steindler, M.J.

    1978-05-01

    Literature describing previous and current work on the encapsulation of solidified high-level waste forms in a metal matrix was reviewed. Encapsulation of either stabilized calcine pellets or glass beads in alloys by casting techniques was concluded to be the most developed and direct approach to fabricating solid metal-matrix waste forms. Further characterizations of the physical and chemical properties of metal-matrix waste forms are still needed to assess the net attributes of metal-encapsulation alternatives. Steady-state heat transfer properties of waste canisters in air and water environments were calculated for four reference waste forms: (1) calcine, (2) glass monoliths, (3) metal-encapsulated calcine, and (4) metal-encapsulated glass beads. A set of criteria for the maximum allowable canister centerline and surface temperatures and heat generation rates per canister at the time of shipment to a Federal repository was assumed, and comparisons were made between canisters of these reference waste forms of the shortest time after reactor discharge that canisters could be filled and the subsequent ''interim'' storage times prior to shipment to a Federal repository for various canister diameters and waste ages. A reference conceptual flowsheet based on existing or developing technology for encapsulation of stabilized calcine pellets is discussed. Conclusions and recommendations are presented

  3. Review of metal-matrix encapsulation of solidified radioactive high-level waste

    Energy Technology Data Exchange (ETDEWEB)

    Jardine, L J; Steindler, M J

    1978-05-01

    Literature describing previous and current work on the encapsulation of solidified high-level waste forms in a metal matrix was reviewed. Encapsulation of either stabilized calcine pellets or glass beads in alloys by casting techniques was concluded to be the most developed and direct approach to fabricating solid metal-matrix waste forms. Further characterizations of the physical and chemical properties of metal-matrix waste forms are still needed to assess the net attributes of metal-encapsulation alternatives. Steady-state heat transfer properties of waste canisters in air and water environments were calculated for four reference waste forms: (1) calcine, (2) glass monoliths, (3) metal-encapsulated calcine, and (4) metal-encapsulated glass beads. A set of criteria for the maximum allowable canister centerline and surface temperatures and heat generation rates per canister at the time of shipment to a Federal repository was assumed, and comparisons were made between canisters of these reference waste forms of the shortest time after reactor discharge that canisters could be filled and the subsequent ''interim'' storage times prior to shipment to a Federal repository for various canister diameters and waste ages. A reference conceptual flowsheet based on existing or developing technology for encapsulation of stabilized calcine pellets is discussed. Conclusions and recommendations are presented.

  4. Mining Waste Classification and Quantity of Non-Metal Minesin Slovenia

    Directory of Open Access Journals (Sweden)

    Ana Burger

    2007-06-01

    Full Text Available Mining is an important human activity that creates wealth and supplies materials for maintaining standard of living and further human development. However, mining has also negative impacts on the environment and society. One of them is the production of mining waste throughout the entire mining cycle, in particular in the mine development and operation /production stage.Due to the EU Directive 2006/21/EC on the management of waste from the extractive industries and its implementation in Member state, estimation on quality and quantity of mining waste from active non-metal mines in Slovenia was carried out. In the selected mines mining and processing was closely examined. With material flow analysis quantity and characteristics of mining waste were defined for several mines of different commodities.Data on mining waste were afterwards generalized in order to get an overall country evaluation on mining waste “production” of non-metal mines.Mining waste as a result of mining and beneficiation processes in non-metal mines of Slovenia is either inert or non-hazardous. Most of the mining waste is used for mine reclamation running simultaneously with the production phase. The largest amounts of mining waste per unit produced are created in dimension stone industry. Since the dimensionstone production is small, the waste amount is negligible. Large quantities of mining waste are produced in crushed stone and, sand and gravel operations, because aggregate production is pretty large with regard to other non-metals production in Slovenia. We can therefore conclude that large quantities of mining waste from non-metal mines, which are mostly used in reclamation and for side products, do not represent danger to the environment.

  5. Recovery of precious metals from industrial wastes using membrane separation

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Jin Ki; Lee, Jae Chun; Youn, In Ju [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of)

    1995-12-01

    The purpose of the research is to develop a membrane technology for the recovery of Au by the concentration of used cyanide solution. Au and Ag have been widely used in various advanced technology due to their excellent physical and chemical properties. In most of their application, they were electrodeposited in the cyanide solution. The solution was also used as an etchant for the decorative gold alloys such as 14 K and 18 K. Due to the expanding related industry, the amount of used cyanide solution has been greatly increased. The used solution normally contains about 1-3 g/1 of Au. Due to their high prices various separation method has been developed and commercialized for long time. The concentration method which removes water offers various advantages like the reduction of used solution, the needless of additional cyanide, and the increase in the recovery rate. The main objective of the study was laid in the development of an economical recovery process for precious metals including Au from used cyanide solution. To achieve this goal related processes were reviewed comprehensively focussing on the membrane process and the concentration process. The feasibility of membrane process was evaluated by the measurement of separation efficiency and concentration efficiency of cyanide. In addition, various CN analysis was compared in order to develop a simple and routine procedure for future experiment. The process does not require additional cyanide and thus prevents further environmental contamination. It is economical because the recovery can be increased by the concentration of the solution during the recovery process. In addition, it can be applied to other metals waste system due to the reduced recovery process by concentration. The used water can also be reused. (author). 23 refs., 16 figs., 5 tabs.

  6. Highly selective and efficient removal of fluoride from ground water by layered Al-Zr-La Tri-metal hydroxide

    Science.gov (United States)

    Zhou, Jian; Zhu, Wenkun; Yu, Jie; Zhang, Hongping; Zhang, Yongde; Lin, Xiaoyan; Luo, Xuegang

    2018-03-01

    A novel layered Zr-Al-La tri-metal composite (AZL) was fabricated via co-precipitation method for fluoride removal. The as-prepared adsorbent was characterized by various technologies, and its adsorption behaviors to fluoride were thoroughly carried out to investigate the fluoride removal performance. The results showed that the layered structure existed and the AZL exhibited the maximum adsorption capacity of 90.48 mg g-1 at 308 K and pH 3.0 from the Langmuir isotherm model. The adsorption kinetics was well fitted by the pseudo-second-order equation, and the adsorption isotherms were well described by the Langmuir equation. Adsorption thermodynamics result was indicative of endothermic reaction in the process of adsorption of AZL to fluoride. The as-prepared AZL composite has excellent fluoride removal performance for the practical ground water and satisfies the permissible limit of fluoride in drinking water recommended by Chinese Standard. In addition, based on the characterization, the adsorption mechanism of fluoride on AZL was proposed, including electrostatic interaction between the protonated surface of AZL and fluoride, as well as ion-exchange by hydroxyl group and fluoride.

  7. The study of heavy metals leaching from waste foundry sands using a one-step extraction

    Directory of Open Access Journals (Sweden)

    Bożym Marta

    2017-01-01

    Full Text Available There are a number of leaching test which are used to evaluate the effect of foundry waste disposal on the environment (TCLP, SPLP, ASTM at al.. Because the spent foundry sand are usually deposited at the ground level and they have a similar structure to the soil, survey mobility of metals using the same methods seems appropriate. One-step extraction allows for the evaluation of the mobility and bioavailability of metals in soil and waste. Waste foundry sands have been successfully used as a component in manufactured soils in U.S., but concern over metal contamination must be eliminated before considering this direction of use. The study evaluated the leaching of heavy metals (Cd, Pb, Cu, Zn, Cr, Ni from deposited waste foundry sands. The overall, as well as heavy metals were extracted by different type of extractants: H2O, CH3COOH, HCl, EDTA, MgCl2 and NaCOOH. These extractants are most commonly used to study the mobility and bioavailability of metals in soil and waste. In the present study applicable standards and methodology described in the literature in analysis were used. The results allowed to evaluate the bioavailability of metals leached from those wastes.

  8. Safety evaluation of the leaching of metals from the printed graphic product wastes

    Directory of Open Access Journals (Sweden)

    Savka Adamović

    2015-09-01

    Full Text Available Due to the technological development of the graphic production, the environment is being faced with a large amount of printed graphic product wastes, especially packaging materials (paper, cardboard, paper and plastic bags, films, etc, but it is also being faced with the problem of their disposal. Many printing inks and coatings used in the production of the printed graphic product contain metals which, after the disposal of graphic waste, can migrate to different systems and have a negative influence on the environment. Because of that, the concentration levels of metals (zinc, copper, chromium, cadmium, lead, and nickel in the printed graphic product wastes have firstly been determined, and then the impact of those metals, through their migration from the printed graphic product wastes to the simulated environmental mediums with different pH values (acidic and neutral, has been estimated. Based on the experimentally obtained concentrations of metals that have migrated from the printed graphic product wastes to the neutral solution and based on the theoretical distribution coefficient, the concentration of metals in the soil of illegal and municipal landfills, which represents the contribution to the overall metal concentration in the soil due to the migration from the waste printed graphic materials, has been calculated. Also, a comparison between the experimentally obtained metal concentrations and the literature values has been conducted, and an evaluation of their influence on the quality of soil has been given.

  9. Integrated chemical/biological treatment of paint stripper mixed waste: Metals toxicity and separation

    International Nuclear Information System (INIS)

    Vanderberg-Twary, L.; Grumbine, R.K.; Foreman, T.; Hanners, J.L.; Brainard, J.R.; Sauer, N.N.; Unkefer, P.J.

    1995-01-01

    The DOE complex has generated vast quantities of complex heterogeneous mixed wastes. Paint stripper waste (PSW) is a complex waste that arose from decontamination and decommissioning activities. It contains paint stripper, cheesecloth, cellulose-based paints with Pb and Cr, and suspect Pu. Los Alamos National Laboratory has 150--200 barrels of PSW and other national laboratories such as Rocky Flats Plant have many more barrels of heterogeneous waste. Few technologies exist that can treat this complex waste. Our approach to solving this problem is the integration of two established technologies: biodegradation and metals chelation

  10. Direct conversion of radioactive and chemical waste containing metals, ceramics, amorphous solids, and organics to glass

    International Nuclear Information System (INIS)

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.

    1994-01-01

    The Glass Material Oxidation and Dissolution System (CMODS) is a new process for direct conversion of radioactive, mixed, and chemical wastes to glass. The wastes can be in the chemical forms of metals, ceramics, amorphous solids, and organics. GMODS destroys organics and it incorporates heavy metals and radionuclides into a glass. Processable wastes may include miscellaneous spent fuels (SF), SF hulls and hardware, plutonium wastes in different forms, high-efficiency particulate air (HEPA) filters, ion-exchange resins, failed equipment, and laboratory wastes. Thermodynamic calculations indicate theoretical feasibility. Small-scale laboratory experiments (< 100 g per test) have demonstrated chemical laboratory feasibility for several metals. Additional work is needed to demonstrate engineering feasibility

  11. Modeling corrosion and constituent release from a metal waste form

    International Nuclear Information System (INIS)

    Bauer, T. H.; Fink, J. K.; Abraham, D. P.; Johnson, I.; Johnson, S. G.; Wigeland, R. A.

    2000-01-01

    Several ANL ongoing experimental programs have measured metal waste form (MWF) corrosion and constituent release. Analysis of this data has initiated development of a consistent and quantitative phenomenology of uniform aqueous MWF corrosion. The effort so far has produced a preliminary fission product and actinide release model based on measured corrosion rates and calibrated by immersion test data for a 90 C J-13 and concentrated J-13 solution environment over 1-2 year exposure times. Ongoing immersion tests of irradiated and unirradiated MWF samples using more aggressive test conditions and improved tracking of actinides will serve to further validate, modify, and expand the application base of the preliminary model-including effects of other corrosion mechanisms. Sample examination using both mechanical and spectrographic techniques will better define both the nature and durability of the protective barrier layer. It is particularly important to assess whether the observations made with J-13 solution at 900 C persist under more aggressive conditions. For example, all the multiplicative factors in Table 1 implicitly assume the presence of protective barriers. Under sufficiently aggressive test conditions, such protective barriers may very well be altered or even eliminated

  12. Lauryl Amine as heavy metal collector of boiler ash from pulp and paper mill waste

    Science.gov (United States)

    Sembiring, M. P.; Kaban, J.; Bangun, N.; Saputra, E.

    2018-04-01

    Theincreasing of demand of pulp and paper products, will following with the growing the pulp and paper industryand generate significant mill waste. The total waste reached 1/3 of the amount raw materials used and ash boiler is the waste with the largest percentage of 52%. For that it takes effort to manage the existing waste. The boiler ash contained the chemical elements, it can be utilized such as fertilizer, because it also contains transition metals in form of heavy metal such as Cadmium (Cd), Cobalt (Co), Chrome (Cr), Cupprum (Cu), Ferrum (Fe), Nickel (Ni), and Zinc (Zn), the use of boiler ash must follow the threshold specified by the Government. Several studies have been undertaken to reduce and extract heavy metals from ash and sand of the boiler by using carbon dioxide as its ligand. Eelectrochemical method was used to remove and recovery of heavy metals from the incenerator. This study focused on removal of heavy metals using Lauryl Amine as collector and three solvents namely Dichloromethane, Ethanol and n-Hexane. The treatmentswas able to extract the heavy metal and generally reduce the heavy metal content of ash boiler pulp and paper mill waste. The combination treatment used toreduce the heavy metal content of 5 gram Lauryl Amine collector in Dichloromethane solvent for 4 hours process time.

  13. Production of novel ceramic materials from coal fly ash and metal finishing wastes

    Energy Technology Data Exchange (ETDEWEB)

    Little, M.R.; Adell, V.; Cheeseman, C.R. [Centre for Environmental Control and Waste Management, Department of Civil and Environmental Engineering, Skempton Building, Imperial College London, London SW7 2AZ (United Kingdom); Boccaccini, A.R. [Department of Materials, Imperial College London, Prince Consort Road, London SW7 2BP (United Kingdom)

    2008-09-15

    Fly ash from coal fired power stations is a potential raw material for the production of ceramic tiles, bricks and blocks. Previous work has demonstrated that the addition of metals can significantly alter fly ash sintering. Metal finishing produces problematic waste filter cakes and sludges that are increasingly difficult to dispose of to landfill. The objective of this research was to investigate the effect of selected metal finishing wastes on the properties of sintered fly ash. A 10 wt.% addition of dried metal finishing sludge obtained from the phosphate bath at a tri-cationic phosphating operation significantly reduced the sintering temperature for maximum density by approximately 75 C. The addition of the phosphate bath sludge also reduced leaching of As, to the extent that fly ash ceramics containing this waste would be classified as inert. Potential industrial applications for these novel waste-derived ceramic materials are discussed. (author)

  14. Design of an innovative, ecological portable waste compressor for in-house recycling of paper, plastic and metal packaging waste.

    Science.gov (United States)

    Xevgenos, D; Athanasopoulos, N; Kostazos, P K; Manolakos, D E; Moustakas, K; Malamis, D; Loizidou, M

    2015-05-01

    Waste management in Greece relies heavily on unsustainable waste practices (mainly landfills and in certain cases uncontrolled dumping of untreated waste). Even though major improvements have been achieved in the recycling of municipal solid waste during recent years, there are some barriers that hinder the achievement of high recycling rates. Source separation of municipal solid waste has been recognised as a promising solution to produce high-quality recycled materials that can be easily directed to secondary materials markets. This article presents an innovative miniature waste separator/compressor that has been designed and developed for the source separation of municipal solid waste at a household level. The design of the system is in line with the Waste Framework Directive (2008/98/EC), since it allows for the separate collection (and compression) of municipal solid waste, namely: plastic (polyethylene terephthalate and high-density polyethylene), paper (cardboard and Tetrapak) and metal (aluminium and tin cans). It has been designed through the use of suitable software tools (LS-DYNA, INVENTROR and COMSOL). The results from the simulations, as well as the whole design process and philosophy, are discussed in this article. © The Author(s) 2015.

  15. Structural transformation of nickel hydroxide films during anodic oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Crocker, Robert W. [Univ. of California, Berkeley, CA (United States); Muller, Rolf H. [Univ. of California, Berkeley, CA (United States)

    1992-05-01

    The transformation of anodically formed nickel hydroxide/oxy-hydroxide electrodes has been investigated. A mechanism is proposed for the anodic oxidation reaction, in which the reaction interface between the reduced and oxidized phases of the electrode evolves in a nodular topography that leads to inefficient utilization of the active electrode material. In the proposed nodular transformation model for the anodic oxidation reaction, nickel hydroxide is oxidized to nickel oxy-hydroxide in the region near the metal substrate. Since the nickel oxy-hydroxide is considerably more conductive than the surrounding nickel hydroxide, as further oxidation occurs, nodular features grow rapidly to the film/electrolyte interface. Upon emerging at the electrolyte interface, the reaction boundary between the nickel hydroxide and oxy-hydroxide phases spreads laterally across the film/electrolyte interface, creating an overlayer of nickel oxy-hydroxide and trapping uncharged regions of nickel hydroxide within the film. The nickel oxy-hydroxide overlayer surface facilitates the oxygen evolution side reaction. Scanning tunneling microscopy of the electrode in its charged state revealed evidence of 80 - 100 Angstrom nickel oxy-hydroxide nodules in the nickel hydroxide film. In situ spectroscopic ellipsometer measurements of films held at various constant potentials agree quantitatively with optical models appropriate to the nodular growth and subsequent overgrowth of the nickel oxy-hydroxide phase. A two-dimensional, numerical finite difference model was developed to simulate the current distribution along the phase boundary between the charged and uncharged material. The model was used to explore the effects of the physical parameters that govern the electrode behavior. The ratio of the conductivities of the nickel hydroxide and oxy-hydroxide phases was found to be the dominant parameter in the system.

  16. Structural transformation of nickel hydroxide films during anodic oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Crocker, R.W.; Muller, R.H.

    1992-05-01

    The transformation of anodically formed nickel hydroxide/oxy-hydroxide electrodes has been investigated. A mechanism is proposed for the anodic oxidation reaction, in which the reaction interface between the reduced and oxidized phases of the electrode evolves in a nodular topography that leads to inefficient utilization of the active electrode material. In the proposed nodular transformation model for the anodic oxidation reaction, nickel hydroxide is oxidized to nickel oxy-hydroxide in the region near the metal substrate. Since the nickel oxy-hydroxide is considerably more conductive than the surrounding nickel hydroxide, as further oxidation occurs, nodular features grow rapidly to the film/electrolyte interface. Upon emerging at the electrolyte interface, the reaction boundary between the nickel hydroxide and oxy-hydroxide phases spreads laterally across the film/electrolyte interface, creating an overlayer of nickel oxy-hydroxide and trapping uncharged regions of nickel hydroxide within the film. The nickel oxy-hydroxide overlayer surface facilitates the oxygen evolution side reaction. Scanning tunneling microscopy of the electrode in its charged state revealed evidence of 80 {endash} 100 Angstrom nickel oxy-hydroxide nodules in the nickel hydroxide film. In situ spectroscopic ellipsometer measurements of films held at various constant potentials agree quantitatively with optical models appropriate to the nodular growth and subsequent overgrowth of the nickel oxy-hydroxide phase. A two-dimensional, numerical finite difference model was developed to simulate the current distribution along the phase boundary between the charged and uncharged material. The model was used to explore the effects of the physical parameters that govern the electrode behavior. The ratio of the conductivities of the nickel hydroxide and oxy-hydroxide phases was found to be the dominant parameter in the system.

  17. Separation of palladium from high-level waste using metal ferro cyanide loaded resins

    International Nuclear Information System (INIS)

    Valsala, T.P.; Joseph, Annie; Yeotikar, R.G.

    2005-01-01

    High-level waste (HLW) is generated during reprocessing of spent fuel. HLW contains corrosion products, unextracted actinides, process chemicals and fission products. A recent trend is there to consider waste as a source of wealth. Among the fission products separation and recovery of platinum group metals have gained great attention. HLW is a good source of palladium of the platinum group metal. The present study shows the feasibility of ion exchange separation of Pd from HLW. (author)

  18. Immobilization of metal wastes by reaction with H2S in anoxic basins. Concept and Elaboration

    NARCIS (Netherlands)

    Schuiling, R.D.

    2013-01-01

    Metal wastes are produced in large quantities by a number of industries. Their disposal in isolated waste deposits is certain to cause many subsequent problems, because every material will sooner or later return to the geochemical cycle. The sealing of disposal sites usually starts to

  19. Examinations of content of heavy metals in municipal solid waste and produced compost

    International Nuclear Information System (INIS)

    Golimowski, J.; Tykarska, A.; Orzechowska, K.

    1993-01-01

    The basic methods of utilization of municipal solid waste are biothermic and aerobic methods to compost. The content of heavy metals in composts depends on the initial their content in wastes as well as on the compost process. The voltammetric method has been applied for measurement of concentration of Zn, Cd, Pb, Cu, Cr, Ni and Hg in the waste and composts samples. (author). 24 refs, 2 figs, 3 tabs

  20. Reducing the leachability of nitrate, phosphorus and heavy metals from soil using waste material

    Directory of Open Access Journals (Sweden)

    Faridullah

    Full Text Available Abstract Contaminants like nitrate (NO3, phosphorus (P and heavy metals in water are often associated with agricultural activities. Various soil and water remediation techniques have been employed to reduce the risk associated with these contaminants. A study was conducted to examine the extent of leaching of heavy metals (Cd, Ni, Pb and Cr, NO3 and P. For this purpose sandy and silt loam soils were amended with different waste materials, namely wood ash, solid waste ash, vegetable waste, charcoal, and sawdust. The soils were saturated with wastewater. Irrespective of the waste applied, the pH and EC of the amended soils were found to be greater than the control. Charcoal, sawdust and wood ash significantly decreased heavy metals, nitrate and phosphorus concentrations in the leachate. Treatments were more efficient for reducing Ni than other heavy metals concentrations. Waste amendments differed for heavy metals during the process of leaching. Heavy metals in the soil were progressively depleted due to the successive leaching stages. This research suggests that waste material may act as an adsorbent for the above contaminants and can reduce their leachability in soils.

  1. Application of a modified electrochemical system for surface decontamination of radioactive metal waste

    International Nuclear Information System (INIS)

    Lee, J.H.; Lim, Y.K.; Yang, H.Y.; Shin, S.W.; Song, M.J.

    2003-01-01

    Conventional and modified electrolytic decontamination experiments were performed in a solution of sodium sulfate for the decontamination of carbon steel as the simulated metal wastes which are generated in large amounts from nuclear power plants. The effect of reaction time, current density and concentration of electrolytes in the modified electrolytic decontamination system were examined to remove the surface contamination of the simulated radioactive metal wastes. As for the results of this research, the modified electrochemical decontamination process can decontaminate more effectively than the conventional decontamination process by applying different anode material which causes higher induced electro-motive forces. When 0.5 M sodium sulfate, 0.4 A/cm 2 current density and 30 minutes reaction time were applied in the modified process, a 16 μm thickness change that is expected to remove most surface contamination in radioactive metal wastes was achieved on carbon steel which is the main material of radioactive metal waste in nuclear power plants. The decontamination efficiency of metal waste showed similar results with the small and large lab-scale modified electrochemical system. The application of this modified electrolytic decontamination system is expected to play a considerable role for decontamination of radioactive metal waste in nuclear power plants in the near future. (author)

  2. Heavy metal vaporization and abatement during thermal treatment of modified wastes

    International Nuclear Information System (INIS)

    Rio, S.; Verwilghen, C.; Ramaroson, J.; Nzihou, A.; Sharrock, P.

    2007-01-01

    This study examines the vaporization percentage and partitioning of heavy metals Cd, Pb and Zn during thermal treatment of wastes with added PVC, heavy metals or phosphate, and the efficiency of sorbents for removal of these metallic compounds in flue gas of an industrial solid waste incinerator. Firstly, vaporization experiments were carried out to determine the behavior of heavy metals during combustion under various conditions (type of waste, temperature, presence of chloride or phosphate ...). The experimental results show relatively high vaporization percentage of metallic compounds within fly ash and limestone matrix while heavy metals within sediments treated with phosphoric acid are less volatile. Vaporization of metals increases with increasing temperature and with chloride addition. The thermal behavior of the selected heavy metals and their removal by sorbents (sodium bicarbonate, activated carbon) was also studied in an industrial solid waste incinerator. These pilot scale experiments confirm that heavy metals are concentrated in fly ashes and cyclone residues, thus effectively controlling their release to the atmosphere

  3. A Reactive Manganese(IV)-Hydroxide Complex: A Missing Intermediate in Hydrogen Atom Transfer by High-Valent Metal-Oxo Porphyrinoid Compounds.

    Science.gov (United States)

    Zaragoza, Jan Paulo T; Siegler, Maxime A; Goldberg, David P

    2018-03-15

    High-valent metal-hydroxide species are invoked as critical intermediates in both catalytic, metal-mediated O 2 activation (e.g., by Fe porphyrin in Cytochrome P450) and O 2 production (e.g., by the Mn cluster in Photosystem II). However, well-characterized mononuclear M IV (OH) complexes remain a rarity. Herein we describe the synthesis of Mn IV (OH)(ttppc) (3) (ttppc = tris(2,4,6-triphenylphenyl) corrole), which has been characterized by X-ray diffraction (XRD). The large steric encumbrance of the ttppc ligand allowed for isolation of 3. The complexes Mn V (O)(ttppc) (4) and Mn III (H 2 O)(ttppc) (1·H 2 O) were also synthesized and structurally characterized, providing a series of Mn complexes related only by the transfer of hydrogen atoms. Both 3 and 4 abstract an H atom from the O-H bond of 2,4-di- tert-butylphenol (2,4-DTBP) to give a radical coupling product in good yield (3 = 90(2)%, 4 = 91(5)%). Complex 3 reacts with 2,4-DTBP with a rate constant of k 2 = 2.73(12) × 10 4 M -1 s -1 , which is ∼3 orders of magnitude larger than 4 ( k 2 = 17.4(1) M -1 s -1 ). Reaction of 3 with a series of para-substituted 2,6-di- tert-butylphenol derivatives (4-X-2,6-DTBP; X = OMe, Me, tBu, H) gives rate constants in the range k 2 = 510(10)-36(1.4) M -1 s -1 and led to Hammett and Marcus plot correlations. Together with kinetic isotope effect measurements, it is concluded that O-H cleavage occurs by a concerted H atom transfer (HAT) mechanism and that the Mn IV (OH) complex is a much more powerful H atom abstractor than the higher-valent Mn V (O) complex, or even some Fe IV (O) complexes.

  4. Dissolvable layered double hydroxide as an efficient nanosorbent for centrifugeless air-agitated dispersive solid-phase extraction of potentially toxic metal ions from bio-fluid samples

    International Nuclear Information System (INIS)

    Rajabi, Maryam; Arghavani-Beydokhti, Somayeh; Barfi, Behruz; Asghari, Alireza

    2017-01-01

    In the present work, a novel nanosorbent namely layered double hydroxides with 4-amino-5-hydroxyl-2,7-naphthalendisulfonic acid monosodium salt interlayer anion (Mg-Al-AHNDA-LDH) was synthesized and applied as a dissolvable nanosorbent in a centrifugeless ultrasound-enhanced air-agitated dispersive solid-phase extraction (USE-AA-D-SPE) method. This method was used for the separation and preconcentration of some metal ions including Cd 2+ , Cr 6+ , Pb 2+ , Co 2+ , and Ni 2+ prior to their determination using the micro-sampling flame atomic absorption spectrometry (MS-FAAS) technique. The most interesting aspect of this nanosorbent is its immediate dissolvability at pH values lower than 4. This capability drastically eliminates the elution step, leading to a great improvement in the extraction efficiency and a decrease in the extraction time. Also in this method, the use of a syringe nanofilter eliminates the need for the centrifugation step, which is time-consuming and essentially causes the analysis to be off-line. Several effective parameters governing the extraction efficiency including the sample solution pH, amount of nanosorbent, eluent condition, number of air-agitation cycles, and sonication time were investigated and optimized. Under the optimized conditions, the good linear dynamic ranges of 2–70, 6–360, 7–725, 7–370, and 8–450 ng mL −1 for the Cd 2+ , Cr 6+ , Pb 2+ , Co 2+ and Ni 2+ ions, respectively, with the correlation of determinations (R 2 s) higher than 0.997 were obtained. The limits of detection (LODs) were found to be 0.6, 1.7, 2.0, 2.1, and 2.4 for the Cd 2+ , Cr 6+ , Pb 2+ , Co 2+ , and Ni 2+ ions, respectively. The intra-day and inter-day precisions (percent relative standard deviations (%RSDs) (n = 5)) were below 7.8%. The proposed method was also successfully applied for the extraction and determination of the target ions in different biological fluid and tap water samples. - Highlights: • A novel centrifugeless dispersive

  5. Dissolvable layered double hydroxide as an efficient nanosorbent for centrifugeless air-agitated dispersive solid-phase extraction of potentially toxic metal ions from bio-fluid samples

    Energy Technology Data Exchange (ETDEWEB)

    Rajabi, Maryam, E-mail: mrajabi@semnan.ac.ir; Arghavani-Beydokhti, Somayeh; Barfi, Behruz; Asghari, Alireza

    2017-03-08

    In the present work, a novel nanosorbent namely layered double hydroxides with 4-amino-5-hydroxyl-2,7-naphthalendisulfonic acid monosodium salt interlayer anion (Mg-Al-AHNDA-LDH) was synthesized and applied as a dissolvable nanosorbent in a centrifugeless ultrasound-enhanced air-agitated dispersive solid-phase extraction (USE-AA-D-SPE) method. This method was used for the separation and preconcentration of some metal ions including Cd{sup 2+}, Cr{sup 6+}, Pb{sup 2+}, Co{sup 2+}, and Ni{sup 2+} prior to their determination using the micro-sampling flame atomic absorption spectrometry (MS-FAAS) technique. The most interesting aspect of this nanosorbent is its immediate dissolvability at pH values lower than 4. This capability drastically eliminates the elution step, leading to a great improvement in the extraction efficiency and a decrease in the extraction time. Also in this method, the use of a syringe nanofilter eliminates the need for the centrifugation step, which is time-consuming and essentially causes the analysis to be off-line. Several effective parameters governing the extraction efficiency including the sample solution pH, amount of nanosorbent, eluent condition, number of air-agitation cycles, and sonication time were investigated and optimized. Under the optimized conditions, the good linear dynamic ranges of 2–70, 6–360, 7–725, 7–370, and 8–450 ng mL{sup −1} for the Cd{sup 2+}, Cr{sup 6+}, Pb{sup 2+}, Co{sup 2+}and Ni{sup 2+} ions, respectively, with the correlation of determinations (R{sup 2}s) higher than 0.997 were obtained. The limits of detection (LODs) were found to be 0.6, 1.7, 2.0, 2.1, and 2.4 for the Cd{sup 2+}, Cr{sup 6+}, Pb{sup 2+}, Co{sup 2+}, and Ni{sup 2+} ions, respectively. The intra-day and inter-day precisions (percent relative standard deviations (%RSDs) (n = 5)) were below 7.8%. The proposed method was also successfully applied for the extraction and determination of the target ions in different biological fluid

  6. Modeling the degradation of a metallic waste form intended for geologic disposal

    International Nuclear Information System (INIS)

    Bauer, T.H.; Morris, E.E.

    2007-01-01

    Nuclear reactors operating with metallic fuels have led to development of robust metallic waste forms intended to immobilize hazardous constituents in oxidizing environments. Release data from a wide range of tests where small waste form samples have been immersed in a variety of oxidizing solutions have been analyzed and fit to a mechanistically-derived 'logarithmic growth' form for waste form degradation. A bounding model is described which plausibly extrapolates these fits to long-term degradation in a geologic repository. The resulting empirically-fit degradation model includes dependence on solution pH, temperature, and chloride concentration as well as plausible estimates of statistical uncertainty. (authors)

  7. Development for recycle of dismantled metal wastes by decommissioning of NPP

    International Nuclear Information System (INIS)

    Asami, Tomohiro; Sato, Hiroshi; Hatakeyama, Mutsuo

    2007-01-01

    For recycle of dismantled metal wastes generated by the decommissioning of nuclear power plant, we examined a melting test for melting characterization of stainless steel scrap, designed the conceptual process to produce the recycle products, and developed a recycle cost evaluation code which is useful to make a rational planning for the waste management program (cost, determination of process, etc.) of these metal wastes. This report gives the summary of these development carried out from 2001 to 2005. This work was performed under the sponsorship of Ministry of Education, Culture, Sports, Science and Technology of Japan. (author)

  8. Generation of copper rich metallic phases from waste printed circuit boards

    Energy Technology Data Exchange (ETDEWEB)

    Cayumil, R. [Centre for Sustainable Materials Research and Technology (SMaRT), School of Materials Science and Engineering, The University of New South Wales, Sydney, NSW 2052 (Australia); Khanna, R., E-mail: ritakhanna@unsw.edu.au [Centre for Sustainable Materials Research and Technology (SMaRT), School of Materials Science and Engineering, The University of New South Wales, Sydney, NSW 2052 (Australia); Ikram-Ul-Haq, M.; Rajarao, R. [Centre for Sustainable Materials Research and Technology (SMaRT), School of Materials Science and Engineering, The University of New South Wales, Sydney, NSW 2052 (Australia); Hill, A. [CSIRO Process Science and Engineering, Clayton, Melbourne, VIC 3168 (Australia); Sahajwalla, V. [Centre for Sustainable Materials Research and Technology (SMaRT), School of Materials Science and Engineering, The University of New South Wales, Sydney, NSW 2052 (Australia)

    2014-10-15

    Highlights: • Recycling and material recovery from waste printed circuit boards is very complex. • Thermoset polymers, ceramics and metals are present simultaneously in waste PCBs. • Heat treatment of PCBs was carried out at 1150 °C under inert conditions. • Various metallic phases could be segregated out as copper based metallic droplets. • Carbon and ceramics residues can be further recycled in a range of applications. - Abstract: The rapid consumption and obsolescence of electronics have resulted in e-waste being one of the fastest growing waste streams worldwide. Printed circuit boards (PCBs) are among the most complex e-waste, containing significant quantities of hazardous and toxic materials leading to high levels of pollution if landfilled or processed inappropriately. However, PCBs are also an important resource of metals including copper, tin, lead and precious metals; their recycling is appealing especially as the concentration of these metals in PCBs is considerably higher than in their ores. This article is focused on a novel approach to recover copper rich phases from waste PCBs. Crushed PCBs were heat treated at 1150 °C under argon gas flowing at 1 L/min into a horizontal tube furnace. Samples were placed into an alumina crucible and positioned in the cold zone of the furnace for 5 min to avoid thermal shock, and then pushed into the hot zone, with specimens exposed to high temperatures for 10 and 20 min. After treatment, residues were pulled back to the cold zone and kept there for 5 min to avoid thermal cracking and re-oxidation. This process resulted in the generation of a metallic phase in the form of droplets and a carbonaceous residue. The metallic phase was formed of copper-rich red droplets and tin-rich white droplets along with the presence of several precious metals. The carbonaceous residue was found to consist of slag and ∼30% carbon. The process conditions led to the segregation of hazardous lead and tin clusters in the

  9. Generation of copper rich metallic phases from waste printed circuit boards

    International Nuclear Information System (INIS)

    Cayumil, R.; Khanna, R.; Ikram-Ul-Haq, M.; Rajarao, R.; Hill, A.; Sahajwalla, V.

    2014-01-01

    Highlights: • Recycling and material recovery from waste printed circuit boards is very complex. • Thermoset polymers, ceramics and metals are present simultaneously in waste PCBs. • Heat treatment of PCBs was carried out at 1150 °C under inert conditions. • Various metallic phases could be segregated out as copper based metallic droplets. • Carbon and ceramics residues can be further recycled in a range of applications. - Abstract: The rapid consumption and obsolescence of electronics have resulted in e-waste being one of the fastest growing waste streams worldwide. Printed circuit boards (PCBs) are among the most complex e-waste, containing significant quantities of hazardous and toxic materials leading to high levels of pollution if landfilled or processed inappropriately. However, PCBs are also an important resource of metals including copper, tin, lead and precious metals; their recycling is appealing especially as the concentration of these metals in PCBs is considerably higher than in their ores. This article is focused on a novel approach to recover copper rich phases from waste PCBs. Crushed PCBs were heat treated at 1150 °C under argon gas flowing at 1 L/min into a horizontal tube furnace. Samples were placed into an alumina crucible and positioned in the cold zone of the furnace for 5 min to avoid thermal shock, and then pushed into the hot zone, with specimens exposed to high temperatures for 10 and 20 min. After treatment, residues were pulled back to the cold zone and kept there for 5 min to avoid thermal cracking and re-oxidation. This process resulted in the generation of a metallic phase in the form of droplets and a carbonaceous residue. The metallic phase was formed of copper-rich red droplets and tin-rich white droplets along with the presence of several precious metals. The carbonaceous residue was found to consist of slag and ∼30% carbon. The process conditions led to the segregation of hazardous lead and tin clusters in the

  10. Study on the law of heavy metal leaching in municipal solid waste landfill.

    Science.gov (United States)

    Liu, Hui-Hu; Sang, Shu-Xun

    2010-06-01

    Comparative leaching experiments were carried out using leaching medium with different pH to municipal solid waste in the landfill columns in order to investigate the mobility of heavy metals. The leachate pH and oxidation-reduction potential were measured by oxidation-reduction potential analyzer; the contents of heavy metals were measured by inductively coupled plasma mass spectrometry. It is very different in leaching concentrations of heavy metals; the dynamic leaching of heavy metals decreased with the rise of the leaching amount on the whole. Acid leaching medium had definite influence on the leaching of heavy metals in the early landfill, but it had the obvious inhibition effect on the leaching in the middle and late period of landfill; the neutral and alkaline leaching medium are more beneficial to the leaching of heavy metals. Due to the influence of the environment of landfill, the differences of the results in cumulative leaching amount, leaching rate, and leaching intensity of heavy metals are very big. The calculation results of the release rates of heavy metals prove that the orders of the release rates are not identical under different leaching conditions. Acid rain made heavy metals migrate from municipal solid waste to soil and detain in soil more easily; approached neutral and alkaline leaching mediums are more beneficial to leaching of heavy metals in the municipal solid waste and soil with leachate. The field verification of experimental data showed that the law of heavy metal leaching in municipal solid waste revealed by the experiment has a good consistency with the data obtained by municipal solid waste landfill.

  11. Heavy metal pollution of water in waste disposal sites in Port ...

    African Journals Online (AJOL)

    The high concentrations (mg/l) of Fe, Zn, Cd and Mn in the two studied sites indicates that water in these areas may be polluted by these heavy metals and could be toxic for agriculture. Key words: Waste disposal site, Pollution, Heavy metals, Concentrations, Portable water, Toxic, Agriculture, WHO Standard, Port Harcourt ...

  12. Characterization of Irradiated Metal Waste from the Pyrometallurgical Treatment of Used EBR-II Fuel

    Energy Technology Data Exchange (ETDEWEB)

    B.R. Westphal; K.C. Marsden; W.M. McCartin; S.M. Frank; D.D. Keiser, Jr.; T.S. Yoo; D. Vaden; D.G. Cummings; K.J. Bateman; J. J. Giglio; T. P. O' Holleran; P. A. Hahn; M. N. Patterson

    2013-03-01

    As part of the pyrometallurgical treatment of used Experimental Breeder Reactor-II fuel, a metal waste stream is generated consisting primarily of cladding hulls laden with fission products noble to the electrorefining process. Consolidation by melting at high temperature [1873 K (1600 degrees C)] has been developed to sequester the noble metal fission products (Zr, Mo, Tc, Ru, Rh, Te, and Pd) which remain in the iron-based cladding hulls. Zirconium from the uranium fuel alloy (U-10Zr) is also deposited on the hulls and forms Fe-Zr intermetallics which incorporate the noble metals as well as residual actinides during processing. Hence, Zr has been chosen as the primary indicator for consistency of the metal waste. Recently, the first production-scale metal waste ingot was generated and sampled to monitor Zr content for Fe-Zr intermetallic phase formation and validation of processing conditions. Chemical assay of the metal waste ingot revealed a homogeneous distribution of the noble metal fission products as well as the primary fuel constituents U and Zr. Microstructural characterization of the ingot confirmed the immobilization of the noble metals in the Fe-Zr intermetallic phase.

  13. Characterization of inorganic wastes from metal working industries

    International Nuclear Information System (INIS)

    Gomez, A.; Viguri, J.R.; Andres, A.; Irabien, A.; Guise, L.; Magalhaes, J.; Castro, F.

    1999-01-01

    The paper present the results obtained in the characterisation of metalworking wastes, with the sampling of wastes and characterisation data interpretation subjects as the main studied steps. The results of this work allow to establish the environmental impact assessment of the inorganic wastes from a wide range of metalworking processes in order to determine the optimum options to their management (treatment and/or reuses)

  14. An assessment on the recycling opportunities of wastes emanating from scrap metal processing in Mauritius

    International Nuclear Information System (INIS)

    Mauthoor, Sumayya; Mohee, Romeela; Kowlesser, Prakash

    2014-01-01

    Highlights: • Scrap metal processing wastes. • Areas of applications for slag, electric arc furnace dust, mill scale and wastewater sludge. • Waste generation factor of 349.3 kg per ton of steel produced. • Waste management model. - Abstract: This paper presents an assessment on the wastes namely slag, dust, mill scale and sludge resulting from scrap metal processing. The aim of this study is to demonstrate that there are various ways via which scrap metal processing wastes can be reused or recycled in other applications instead of simply diverting them to the landfill. These wastes are briefly described and an overview on the different areas of applications is presented. Based on the results obtained, the waste generation factor developed was 349.3 kg per ton of steel produced and it was reported that slag represents 72% of the total wastes emanating from the iron and steel industry in Mauritius. Finally the suitability of the different treatment and valorisation options in the context of Mauritius is examined

  15. Removal of heavy metal ions from wastewater by chemically modified plant wastes as adsorbents: a review.

    Science.gov (United States)

    Wan Ngah, W S; Hanafiah, M A K M

    2008-07-01

    The application of low-cost adsorbents obtained from plant wastes as a replacement for costly conventional methods of removing heavy metal ions from wastewater has been reviewed. It is well known that cellulosic waste materials can be obtained and employed as cheap adsorbents and their performance to remove heavy metal ions can be affected upon chemical treatment. In general, chemically modified plant wastes exhibit higher adsorption capacities than unmodified forms. Numerous chemicals have been used for modifications which include mineral and organic acids, bases, oxidizing agent, organic compounds, etc. In this review, an extensive list of plant wastes as adsorbents including rice husks, spent grain, sawdust, sugarcane bagasse, fruit wastes, weeds and others has been compiled. Some of the treated adsorbents show good adsorption capacities for Cd, Cu, Pb, Zn and Ni.

  16. Release to the gas phase of metals, S and Cl during combustion of dedicated waste fractions

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; van Lith, Simone Cornelia; Frandsen, Flemming

    2010-01-01

    The release to the gas phase of inorganic elements such as alkali metals. Cl, S, and heavy metals in Waste-to-Energy (WtE) boilers is a challenge. Besides the risk of harmful emissions to the environment, inorganic elements released from the grate may cause severe ash deposition and corrosion...... wood, shoes, automotive shredder waste and PVC (poly-vinyl-chloride). The waste fractions were characterized by use of wet chemical analysis, and, based on the chemical composition of the initial fuel sample and the ash residue after the experiments; the release of inorganic elements was quantified....... The lab-scale release results were then compared with results from a related, full-scale partitioning study, in which test runs with the addition of similar, dedicated waste fractions to a base-load waste had been performed in a grate-fired WtE boiler. In general, the elements Al, Ca, Cr, Cu, Fe, Mg, Si...

  17. Dissolvable layered double hydroxide as an efficient nanosorbent for centrifugeless air-agitated dispersive solid-phase extraction of potentially toxic metal ions from bio-fluid samples.

    Science.gov (United States)

    Rajabi, Maryam; Arghavani-Beydokhti, Somayeh; Barfi, Behruz; Asghari, Alireza

    2017-03-08

    In the present work, a novel nanosorbent namely layered double hydroxides with 4-amino-5-hydroxyl-2,7-naphthalendisulfonic acid monosodium salt interlayer anion (Mg-Al-AHNDA-LDH) was synthesized and applied as a dissolvable nanosorbent in a centrifugeless ultrasound-enhanced air-agitated dispersive solid-phase extraction (USE-AA-D-SPE) method. This method was used for the separation and preconcentration of some metal ions including Cd 2+ , Cr 6+ , Pb 2+ , Co 2+ , and Ni 2+ prior to their determination using the micro-sampling flame atomic absorption spectrometry (MS-FAAS) technique. The most interesting aspect of this nanosorbent is its immediate dissolvability at pH values lower than 4. This capability drastically eliminates the elution step, leading to a great improvement in the extraction efficiency and a decrease in the extraction time. Also in this method, the use of a syringe nanofilter eliminates the need for the centrifugation step, which is time-consuming and essentially causes the analysis to be off-line. Several effective parameters governing the extraction efficiency including the sample solution pH, amount of nanosorbent, eluent condition, number of air-agitation cycles, and sonication time were investigated and optimized. Under the optimized conditions, the good linear dynamic ranges of 2-70, 6-360, 7-725, 7-370, and 8-450 ng mL -1 for the Cd 2+ , Cr 6+ , Pb 2+ , Co 2+ and Ni 2+ ions, respectively, with the correlation of determinations (R 2 s) higher than 0.997 were obtained. The limits of detection (LODs) were found to be 0.6, 1.7, 2.0, 2.1, and 2.4 for the Cd 2+ , Cr 6+ , Pb 2+ , Co 2+ , and Ni 2+ ions, respectively. The intra-day and inter-day precisions (percent relative standard deviations (%RSDs) (n = 5)) were below 7.8%. The proposed method was also successfully applied for the extraction and determination of the target ions in different biological fluid and tap water samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Method of dissolving metal ruthenium

    International Nuclear Information System (INIS)

    Tsuno, Masao; Soda, Yasuhiko; Kuroda, Sadaomi; Koga, Tadaaki.

    1988-01-01

    Purpose: To dissolve and clean metal ruthenium deposited to the inner surface of a dissolving vessel for spent fuel rods. Method: Metal ruthenium is dissolved in a solution of an alkali metal hydroxide to which potassium permanganate is added. As the alkali metal hydroxide used herein there can be mentioned potassium hydroxide, sodium hydroxide and lithium hydroxide can be mentioned, which is used as an aqueous solution from 5 to 20 % concentration in view of the solubility of metal ruthenium and economical merit. Further, potassium permanganate is used by adding to the solution of alkali metal hydroxide at a concentration of 1 to 5 %. (Yoshihara, H.)

  19. Pollution distribution of heavy metals in surface soil at an informal electronic-waste recycling site.

    Science.gov (United States)

    Fujimori, Takashi; Takigami, Hidetaka

    2014-02-01

    We studied distribution of heavy metals [lead (Pb), copper (Cu) and zinc (Zn)] in surface soil at an electronic-waste (e-waste) recycling workshop near Metro Manila in the Philippines to evaluate the pollution size (spot size, small area or the entire workshop), as well as to assess heavy metal transport into the surrounding soil environment. On-site length-of-stride-scale (~70 cm) measurements were performed at each surface soil point using field-portable X-ray fluorescence (FP-XRF). The surface soil at the e-waste recycling workshop was polluted with Cu, Zn and Pb, which were distributed discretely in surface soil. The site was divided into five areas based on the distance from an entrance gate (y-axis) of the e-waste recycling workshop. The three heavy metals showed similar concentration gradients in the y-axis direction. Zn, Pb and Cu concentrations were estimated to decrease to half of their maximum concentrations at ~3, 7 and 7 m from the pollution spot, respectively, inside the informal e-waste recycling workshop. Distance from an entrance may play an important role in heavy metal transport at the soil surface. Using on-site FP-XRF, we evaluated the metal ratio to characterise pollution features of the solid surface. Variability analysis of heavy metals revealed vanishing surficial autocorrelation over metre ranges. Also, the possibility of concentration prediction at unmeasured points using geostatistical kriging was evaluated, and heavy metals had a relative "small" pollution scales and remained inside the original workshop compared with toxic organohalogen compounds. Thus, exposure to heavy metals may directly influence the health of e-waste workers at the original site rather than the surrounding habitat and environmental media.

  20. Potential groundwater pollution from improper oil and metal waste ...

    African Journals Online (AJOL)

    This study, therefore, investigated the potential impact of the waste disposal on groundwater quality in the area. The methods employed involved mapping all the potential waste oil spillage sources and sampling the soils in such areas (at 0 – 30 and 30 – 60 cm depths) and groundwater supply points for laboratory analyses ...

  1. Iron and aluminium oxides containing industrial wastes as adsorbents of heavy metals: Application possibilities and limitations.

    Science.gov (United States)

    Jacukowicz-Sobala, Irena; Ociński, Daniel; Kociołek-Balawejder, Elżbieta

    2015-07-01

    Industrial wastes with a high iron or aluminium oxide content are produced in huge quantities as by-products of water treatment (water treatment residuals), bauxite processing (red mud) and hard and brown coal burning in power plants (fly ash). Although they vary in their composition, the wastes have one thing in common--a high content of amorphous iron and/or aluminium oxides with a large specific surface area, whereby this group of wastes shows very good adsorbability towards heavy metals, arsenates, selenates, etc. But their physical form makes their utilisation quite difficult, since it is not easy to separate the spent sorbent from the solution and high bed hydraulic resistances occur in dynamic regime processes. Nevertheless, because of the potential benefits of utilising the wastes in industrial effluent treatment, this issue attracts much attention today. This study describes in detail the waste generation processes, the chemical structure of the wastes, their physicochemical properties, and the mechanisms of fixing heavy metals and semimetals on the surface of iron and aluminium oxides. Typical compositions of wastes generated in selected industrial plants are given. A detailed survey of the literature on the adsorption applications of the wastes, including methods of their thermal and chemical activation, as well as regeneration of the spent sorbents, is presented. The existing and potential ways of modifying the physical form of the discussed group of wastes, making it possible to overcome the basic limitation on their practical use, are discussed. © The Author(s) 2015.

  2. Removal of heavy metals from waste water of tanning leather ...

    African Journals Online (AJOL)

    The most dominant A. candidus on the isolation plates exhibited the highest activity for biosorption of heavy metals. The results indicate that fungi of contaminated soils have high level of metal biosorption capacities. Keywords: Fungi, industrial wastewater, biosorption, heavy metals. African Journal of Biotechnology Vol.

  3. Dissolution Behaviour of Metal Elements from Several Types of E-waste Using Leaching Test

    Science.gov (United States)

    Nor, Nik Hisyamudin Muhd; Amira Nordin, Nurul; Mohamad, Fariza; Jaibee, Shafizan; Ismail, Al Emran; Omar, Badrul; Fauzi Ahmad, Mohd; Rahim, Abd Khalil Abd; Kamaruddin, Muhamad Khalif Ikhwan Mohd; Turan, Faiz Mohd; Abu Bakar, Elmi; Yokoyama, Seiji

    2017-08-01

    Rapid development of the electrical and electronic was increasing annually due to the demand by the human being. Increasing production of electrical and electronic product led to the increasing of electric and electronic waste or can be called as the e-waste. The UN Environment Programme estimates that the world generates 20-50 million tons of the e-waste each year and the amount is raising three times faster than other forms of municipal waste. This study is focusing on the investigation of the dissolution behaviour of metal element from several types of e-waste by hydrometallurgical process. Leaching test was conducted on the e-waste by using acid as the reagent solution. Prior to the leaching test, manual dismantling, separation, and crushing process were carried out to the e-waste. The e-waste were characterized by Scanning Electron Microcopy (SEM) and the Energy Dispersive X-ray Spectroscopy (EDX) to define the elements inside the sample of e-waste. While the liquid residue from leaching test was analyzed by using Inductively Couple Plasma-Mass Spectrometer (ICP-MS) to define the dissolution behaviour of the metal element that contain in the e-waste. It was found that the longest time for dismantling process was the dismantling of laptop. The dissolution behaviour of Fe, Al, Zn and Pb elements in the e-waste has affected to the increase of pH. The increasing pH led to the reduction of the metals element during leaching process.

  4. Utilizing waste heat from metal industry for drying of organic waste

    OpenAIRE

    Dobric, Sasa

    2014-01-01

    Growing generation of organic waste is a real problem all over the world. This is specifically expressed in the developed countries because the amounts of the waste are larger. Therefore, it implies problem connected with organic waste disposal. In the modern society it is prohibited to dump the waste on landfills. It was necessary to find the solution how to deal with this situation.One of the options is delivering of the organic waste to the burning facilities. In this way it is possible to...

  5. Urban Biomining: Biological Extraction of Metals and Materials from Electronics Waste Using a Synthetic Biology Approach

    Science.gov (United States)

    Urbina-Navarrete, J.; Rothschild, L.

    2016-12-01

    End-of-life electronics waste (e-waste) containing toxic and valuable materials is a rapidly progressing human health and environmental issue. Using synthetic biology tools, we have developed a recycling method for e-waste. Our innovation is to use a recombinant version of a naturally-occurring silica-degrading enzyme to depolymerize the silica in metal- and glass- containing e-waste components, and subsequently, to use engineered bacterial surfaces to bind and separate metals from a solution. The bacteria with bound metals can then be used as "bio-ink" to print new circuits using a novel plasma jet electronics printing technology. Here, we present the results from our initial studies that focus on the specificity of metal-binding motifs for a cognate metal. The candidate motifs that show high affinity and specificity will be engineered into bacterial surfaces for downstream applications in biologically-mediated metal recycling. Since the chemistry and role of Cu in metalloproteins is relatively well-characterized, we are using Cu as a proxy to elucidate metal and biological ligand interactions with various metals in e-waste. We assess the binding parameters of 3 representative classes of Cu-binding motifs using isothermal titration calorimetry; 1) natural motifs found in metalloproteins, 2) consensus motifs, and 3) rationally designed peptides that are predicted, in silico, to bind Cu. Our results indicate that naturally-occurring motifs have relative high affinity and specificity for Cu (association constant for Cu Ka 104 M-1, Zn Ka 103 M-1) when competing ions are present in the aqueous milieu. However, motifs developed through rational design by applying quantum mechanical methods that take into account complexation energies of the elemental binding partners and molecular geometry of the cognate metal, not only show high affinity for the cognate metal (Cu Ka 106 M-1), but they show specificity and discrimination against other metal ions that would be

  6. Development of engineering parameters for the design of metal biosorption waste treatment systems

    Energy Technology Data Exchange (ETDEWEB)

    Graham, W.S.

    1991-12-03

    Untreated landfill leachates and wastes from metal plating and mining operations are sources of environmental contamination by heavy metals. Because of their toxicity and potential for accumulation, the discharge of heavy metals must be controlled. Standard physical and chemical treatments used to remove metals from wastes such as concentration by electro-precipitation, ion exchange, solvent extraction, evaporative recovery, and conventional precipitation, are usually expensive and produce high quantities of sludge. Biosorption is the removal of metals from aqueous solutions by microorganisms. It is called biosorption rather than bioadsorption or bioaccumulation because the mechanisms of removal are not restricted to adsorption or metabolic uptake and so the more general term is preferable and has come to be accepted. In this thesis the focus is one two microorganisms and two metals. However, the possible combinations of conditions such as pH, relative metal molarities, time of contact, and organism are numerous. These experiments are designed to provide optimized parameters to facilitate the design of a functioning biosorption system. The two metals chosen for study are copper and lead in aqueous solution. The two types of microorganisms chosen for testing include an actinomycete and a fungus. The purpose of this research is to identify the significant engineering parameters to be evaluated include reaction rates, equilibrium partitioning of metal ions between those in solution and those removed to the cells, optimum pH for achieving the removal or recovery goal, and biosorption selectivity for one metal over another.

  7. Informal E-waste recycling in developing countries: review of metal(loid)s pollution, environmental impacts and transport pathways.

    Science.gov (United States)

    Ackah, Michael

    2017-11-01

    Crude or primitive recycling practices are often adopted in material resource recovery from E-waste in developing nations. Significant human health and environmental impacts may occur because of such practices. Literature on metal(loid)s pollution during E-waste processing is fragmented. Here, I review the health and environmental impacts of E-waste recycling operations and transport pathways of metal(loid)s, dispersed during operations. This paper is organised into five sections. Section 1 relates to the background of global E-waste generation and legal/illegal trade, citing specific cases from Ghana and other developing nations. Section 2 provides a brief information on sources of metal(loid)s in E-waste. Section 3 describes characteristics of informal E-waste recycling operations in developing nations. Section 4 examines the health and environmental impacts in E-waste recycling while section 5 evaluates major transport pathways of metal(loid)s contaminants.

  8. Noble Metals and Spinel Settling in High Level Waste Glass Melters

    Energy Technology Data Exchange (ETDEWEB)

    Sundaram, S. K.; Perez, Joseph M.

    2000-09-30

    In the continuing effort to support the Defense Waste Processing Facility (DWPF), the noble metals issue is addressed. There is an additional concern about the amount of noble metals expected to be present in the future batches that will be considered for vitrification in the DWPF. Several laboratory, as well as melter-scale, studies have been completed by various organizations (mainly PNNL, SRTC, and WVDP in the USA). This letter report statuses the noble metals issue and focuses at the settling of noble metals in melters.

  9. Yucca Mountain project canister material corrosion studies as applied to the electrometallurgical treatment metallic waste form

    International Nuclear Information System (INIS)

    Keiser, D.D.

    1996-11-01

    Yucca Mountain, Nevada is currently being evaluated as a potential site for a geologic repository. As part of the repository assessment activities, candidate materials are being tested for possible use as construction materials for waste package containers. A large portion of this testing effort is focused on determining the long range corrosion properties, in a Yucca Mountain environment, for those materials being considered. Along similar lines, Argonne National Laboratory is testing a metallic alloy waste form that also is scheduled for disposal in a geologic repository, like Yucca Mountain. Due to the fact that Argonne's waste form will require performance testing for an environment similar to what Yucca Mountain canister materials will require, this report was constructed to focus on the types of tests that have been conducted on candidate Yucca Mountain canister materials along with some of the results from these tests. Additionally, this report will discuss testing of Argonne's metal waste form in light of the Yucca Mountain activities

  10. Carbonized waste for the cut-down of environmental pollution with heavy metals

    Science.gov (United States)

    Gmucová, K.; Morvová, M.; Havránek, E.; Kliman, J.; Košinár, I.; Kunecová, D.; Malakhov, A. I.; Anisimov, Yu. S.; Morva, I.; Siváček, I.; Sýkorová, M.; Šatka, A.

    2011-07-01

    Nowadays, an increasing concern about the treatment and disposal of waters contaminated by toxic heavy metals is noticed. The toxic pollutants must be removed from the sewage water which then is fed back into the materials cycle. Any candidate technology should result in reusable by-products. With this in mind, the aim of the present study is to test a low cost procedure for utilization of the carbonized waste, a product of PET (polyethylene terephthalate) bottles pyrolysis on sand bedding, for this purpose. Both the water present in PET bottles waste and combustion exhaust probably contribute to the conversion of carbon char to activated carbon directly within the pyrolysis oven. Preliminary results, obtained for several heavy metal ions under laboratory conditions are presented and discussed. Adsorption of heavy metals on the carbonized PET waste is tested by both the electrochemical methods and X-ray fluorescence spectrometry. A simple desorption procedure for the regeneration of prepared active carbon is proposed.

  11. Nickel-cobalt hydroxide nanosheets: Synthesis, morphology and electrochemical properties.

    Science.gov (United States)

    Schneiderová, Barbora; Demel, Jan; Zhigunov, Alexander; Bohuslav, Jan; Tarábková, Hana; Janda, Pavel; Lang, Kamil

    2017-08-01

    This paper reports the synthesis, characterization, and electrochemical performance of nickel-cobalt hydroxide nanosheets. The hydroxide nanosheets of approximately 0.7nm thickness were prepared by delamination of layered nickel-cobalt hydroxide lactate in water and formed transparent colloids that were stable for months. The nanosheets were deposited on highly oriented pyrolytic graphite by spin coating, and their electrochemical behavior was investigated by cyclic voltammetry in potassium hydroxide electrolyte. Our method of electrode preparation allows for studying the electrochemistry of nanosheets where the majority of the active centers can participate in the charge transfer reaction. The observed electrochemical response was ascribed to mutual compensation of the cobalt and nickel response via electron sharing between these metals in the hydroxide nanosheets, a process that differentiates the behavior of nickel-cobalt hydroxide nanosheets from single nickel hydroxide or cobalt hydroxide nanosheets or their physical mixture. The presence of cobalt in the nickel-cobalt hydroxide nanosheets apparently decreases the time of electrochemical activation of the nanosheet layer, which for the nickel hydroxide nanosheets alone requires more potential sweeps. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. High level waste containing granules coated and embedded in metal as an alternative to HLW glasses

    International Nuclear Information System (INIS)

    Neumann, W.

    1980-01-01

    Simulated high level waste containing granules were overcoated with pyrocarbon or nickel respectively. The coatings were performed by the use of chemical vapour deposition in a fluidized bed. The coated granules were embedded in an aluminium-silicon-alloy to improve the dissipation of radiation induced heat. The metal-granules-composites obtained were of improved product stability related to the high level waste containing glasses. (orig.) [de

  13. A bioseparation process for removing heavy metals from waste ...

    African Journals Online (AJOL)

    The role of cell structure, cell wall, micropores and macropores is evaluated in terms of the potential of these biosorbents for metal sequestration. Binding mechanisms are discussed, including the key functional groups involved and the ion-exchange process. Quantification of metal-biomass interactions is fundamental to the ...

  14. Growth and metal bioconcentration by conspecific freshwater macroalgae cultured in industrial waste water

    Directory of Open Access Journals (Sweden)

    Michael B. Ellison

    2014-05-01

    Full Text Available The bioremediation of industrial waste water by macroalgae is a sustainable and renewable approach to the treatment of waste water produced by multiple industries. However, few studies have tested the bioremediation of complex multi-element waste streams from coal-fired power stations by live algae. This study compares the ability of three species of green freshwater macroalgae from the genus Oedogonium, isolated from different geographic regions, to grow in waste water for the bioremediation of metals. The experiments used Ash Dam water from Tarong power station in Queensland, which is contaminated by multiple metals (Al, Cd, Ni and Zn and metalloids (As and Se in excess of Australian water quality guidelines. All species had consistent growth rates in Ash Dam water, despite significant differences in their growth rates in “clean” water. A species isolated from the Ash Dam water itself was not better suited to the bioremediation of that waste water. While there were differences in the temporal pattern of the bioconcentration of metals by the three species, over the course of the experiment, all three species bioconcentrated the same elements preferentially and to a similar extent. All species bioconcentrated metals (Cu, Mn, Ni, Cd and Zn more rapidly than metalloids (As, Mo and Se. Therefore, bioremediation in situ will be most rapid and complete for metals. Overall, all three species of freshwater macroalgae had the ability to grow in waste water and bioconcentrate elements, with a consistent affinity for the key metals that are regulated by Australian and international water quality guidelines. Together, these characteristics make Oedogonium a clear target for scaled bioremediation programs across a range of geographic regions.

  15. Sewage sludge as barrier material for heavy metals in waste landfill

    Directory of Open Access Journals (Sweden)

    Zhang Huyuan

    2016-06-01

    Full Text Available Heavy metal pollutants in the leachate of waste landfill are a potential threat to the environment. In this study, the feasibility of using municipal sewage sludge as barrier material for the containment of heavy metal pollutants from solid waste landfills was evaluated by compaction test and hydraulic conductivity test concerning compaction property, impermeability and heavy metal retardation. Results of the compaction test showed that the maximum dry density of 0.79 g·cm−3 was achieved at the optimum water content of about 60%. The hydraulic conductivities of compacted sewage sludge permeated with synthetic heavy metal solutions were in the range of 1.3×10−8 – 6.2×10−9 cm·s−1, less than 1.0 ×10−7cm·s−1 recommended by regulations for barrier materials. Chemical analyses on the effluent from the hydraulic conductivity tests indicated that the two target heavy metals, Zn and Cd in the permeants were all retarded by compacted sewage sludge, which might be attributed to the precipitation and adsorption of heavy metal ions. The results of this study suggest that specially prepared material from sewage sludge could be used as a barrier for waste landfills for its low permeability and strong retardation to heavy metal pollutants.

  16. Competitive metal sorption and desorption onto Kappaphycus alvarezii, seaweed waste biomass

    International Nuclear Information System (INIS)

    Lee, K.O.; Nazaruddin Ramli; Mamot Said; Musa Ahmad; Suhaimi Mohd Yasir; Arbakariya Ariff

    2011-01-01

    Competitive metal sorption and desorption onto Kappaphycus alvarezii waste biomass were investigated. Metal sorption capacities were 0.82 mg Cr (III)/ g, 0.73 mg Ni (II)/ g, 0.67 mg Cd (II)/ g, 0.65 mg Cu( II)/ g and 0.64 mg Zn (II)/ g in multi metal system. Whereas, desorption efficiencies were 66.08 %, 71.50 % and 80.44 % using 0.1 M HNO 3 , 0.1 M HCl and 0.1 M H 2 SO 4 , respectively. The metal sorption sequence were Cr(III) > Ni(II) > Cd(II) > Cu(II) > Zn(II), while metal desorption sequence were Cd(II) > Zn(II) > Cu(II) > Ni(II) > Cr(III). Fourier transformed infrared spectroscopy (FTIR) technique was used to characterize the seaweed waste biomass. FTIR analysis shown that carbonyl (-C-O) and nitrile (-C≡N) groups interact with the metal ions. The experiments result revealed that Kappaphycus alvarezii waste biomass represent an attractive candidate to remove multi metal ions. (author)

  17. Removal and recovery of radionuclides and toxic metals from wastes, soils and materials

    International Nuclear Information System (INIS)

    Francis, A.J.

    1993-07-01

    A process has been developed at Brookhaven National Laboratory (BNL) for the removal of metals and radionuclides from contaminated materials, soils, and waste sites (Figure 1). In this process, citric acid, a naturally occurring organic complexing agent, is used to extract metals such as Ba, Cd, Cr, Ni, Zn, and radionuclides Co, Sr, Th, and U from solid wastes by formation of water soluble, metal-citrate complexes. Citric acid forms different types of complexes with the transition metals and actinides, and may involve formation of a bidentate, tridentate, binuclear, or polynuclear complex species. The extract containing radionuclide/metal complex is then subjected to microbiological degradation followed by photochemical degradation under aerobic conditions. Several metal citrate complexes are biodegraded and the metals are recovered in a concentrated form with the bacterial biomass. Uranium forms binuclear complex with citric acid and is not biodegraded. The supernatant containing uranium citrate complex is separated and upon exposure to light, undergoes rapid degradation resulting in the formation of an insoluble, stable polymeric form of uranium. Uranium is recovered as a precipitate (uranium trioxide) in a concentrated form for recycling or for appropriate disposal. This treatment process, unlike others which use caustic reagents, does not create additional hazardous wastes for disposal and causes little damage to soil which can then be returned to normal use

  18. Heavy Metal Contamination of Soils around a Hospital Waste Incinerator Bottom Ash Dumps Site.

    Science.gov (United States)

    Adama, M; Esena, R; Fosu-Mensah, B; Yirenya-Tawiah, D

    2016-01-01

    Waste incineration is the main waste management strategy used in treating hospital waste in many developing countries. However, the release of dioxins, POPs, and heavy metals in fly and bottom ash poses environmental and public health concerns. To determine heavy metal (Hg, Pb, Cd, Cr, and Ag) in levels in incinerator bottom ash and soils 100 m around the incinerator bottom ash dump site, ash samples and surrounding soil samples were collected at 20 m, 40 m, 60 m, 80 m, 100 m, and 1,200 m from incinerator. These were analyzed using the absorption spectrophotometer method. The geoaccumulation (I geo) and pollution load indices (PLI) were used to assess the level of heavy metal contamination of surrounding soils. The study revealed high concentrations in mg/kg for, Zn (16417.69), Pb (143.80), Cr (99.30), and Cd (7.54) in bottom ash and these were above allowable limits for disposal in landfill. The study also found soils within 60 m radius of the incinerator to be polluted with the metals. It is recommended that health care waste managers be educated on the implication of improper management of incinerator bottom ash and regulators monitor hospital waste incinerator sites.

  19. Heavy Metal Contamination of Soils around a Hospital Waste Incinerator Bottom Ash Dumps Site

    Directory of Open Access Journals (Sweden)

    M. Adama

    2016-01-01

    Full Text Available Waste incineration is the main waste management strategy used in treating hospital waste in many developing countries. However, the release of dioxins, POPs, and heavy metals in fly and bottom ash poses environmental and public health concerns. To determine heavy metal (Hg, Pb, Cd, Cr, and Ag in levels in incinerator bottom ash and soils 100 m around the incinerator bottom ash dump site, ash samples and surrounding soil samples were collected at 20 m, 40 m, 60 m, 80 m, 100 m, and 1,200 m from incinerator. These were analyzed using the absorption spectrophotometer method. The geoaccumulation (Igeo and pollution load indices (PLI were used to assess the level of heavy metal contamination of surrounding soils. The study revealed high concentrations in mg/kg for, Zn (16417.69, Pb (143.80, Cr (99.30, and Cd (7.54 in bottom ash and these were above allowable limits for disposal in landfill. The study also found soils within 60 m radius of the incinerator to be polluted with the metals. It is recommended that health care waste managers be educated on the implication of improper management of incinerator bottom ash and regulators monitor hospital waste incinerator sites.

  20. Heavy Metal Contamination of Soils around a Hospital Waste Incinerator Bottom Ash Dumps Site

    Science.gov (United States)

    Adama, M.; Esena, R.; Fosu-Mensah, B.; Yirenya-Tawiah, D.

    2016-01-01

    Waste incineration is the main waste management strategy used in treating hospital waste in many developing countries. However, the release of dioxins, POPs, and heavy metals in fly and bottom ash poses environmental and public health concerns. To determine heavy metal (Hg, Pb, Cd, Cr, and Ag) in levels in incinerator bottom ash and soils 100 m around the incinerator bottom ash dump site, ash samples and surrounding soil samples were collected at 20 m, 40 m, 60 m, 80 m, 100 m, and 1,200 m from incinerator. These were analyzed using the absorption spectrophotometer method. The geoaccumulation (I geo) and pollution load indices (PLI) were used to assess the level of heavy metal contamination of surrounding soils. The study revealed high concentrations in mg/kg for, Zn (16417.69), Pb (143.80), Cr (99.30), and Cd (7.54) in bottom ash and these were above allowable limits for disposal in landfill. The study also found soils within 60 m radius of the incinerator to be polluted with the metals. It is recommended that health care waste managers be educated on the implication of improper management of incinerator bottom ash and regulators monitor hospital waste incinerator sites. PMID:27034685

  1. TREATMENT OF METAL-LADEN HAZARDOUS WASTES WITH ADVANCED CLEAN COAL TECHNOLOGY BY-PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    James T. Cobb, Jr.

    2003-09-12

    Metal-laden wastes can be stabilized and solidified using advanced clean coal technology by-products (CCTBs)--fluid bed combustor ash and spray drier solids. These utility-generated treatment chemicals are available for purchase through brokers, and commercial applications of this process are being practiced by treaters of metal-laden hazardous waste. A complex of regulations governs this industry, and sensitivities to this complex has discouraged public documentation of treatment of metal-laden hazardous wastes with CCTBs. This report provides a comprehensive public documentation of laboratory studies that show the efficacy of the stabilization and solidification of metal-laden hazardous wastes--such as lead-contaminated soils and sandblast residues--through treatment with CCTBs. It then describes the extensive efforts that were made to obtain the permits allowing a commercial hazardous waste treater to utilize CCTBs as treatment chemicals and to install the equipment required to do so. It concludes with the effect of this lengthy process on the ability of the treatment company to realize the practical, physical outcome of this effort, leading to premature termination of the project.

  2. Solidification of metal chloride waste from pyrochemical process via dechlorination-chlorination reaction system

    Energy Technology Data Exchange (ETDEWEB)

    Park, H.S.; Cho, I.H.; Lee, K.R.; Choi, J.H.; Eun, H.C.; Kim, I.T.; Park, G.I. [Korea Atomic Energy Research Inst., Deajeon (Korea, Republic of)

    2014-07-01

    The metal chloride wastes generated from the pyro-chemical process to recover uranium and TRUs has been considered as a problematic waste due to the high volatility and low compatibility with conventional silicate glass. Our research group has suggested the dechlorination approach for the solidification of this kind of waste by using a synthetic composite, SAP (SiO{sub 2}-Al{sub 2}O{sub 3}-P{sub 2}O{sub 5}). During the dechlorination, metal elements are chemically interacted with the inorganic composite, SAP, while chlorine is vaporized as gaseous chlorine. Metal elements in the salt were immobilized into phosphate and silicate glass which are uniformly distributed in tens of nm scale. During the dechlorination, gaseous chlorine is captured by Li{sub 2}O-Li{sub 2}O{sub 2} composite that can be converted into metal chloride (LiCl). About 98wt% of oxide composite was converted into LiCl that can be used as an electrolyte in the electrochemical process. The method suggested in this study can provide a chance to minimize the waste volume for the final disposal of salt wastes from a pyro-chemical process. (author)

  3. Assessment of possibility of metal waterjet cutting wastes use in building materials production

    Directory of Open Access Journals (Sweden)

    Skanavi Nataliya

    2017-01-01

    Full Text Available The paper is aimed at studying the composition and properties of the wastes generated during metal waterjet cutting and assessing the possibility of their use in building materials production. The essence of waterjet cutting process, waste generation mechanism, waste accumulation volumes at enterprises are described. The composition and properties of the used abradant – garnet sand is given and the features of its destruction during cutting are revealed. Waterjet cutting wastes are comprehensively studies: average and bulk density, granulometric composition, chemical composition are determined, various fractions are studied with an electronic microscope. It is revealed that during cutting abradant particles are destroyed, a large amount of dust fraction emerges with the particles of cut metal mixed into it. The metal waterjet cutting wastes are found to be very small, practically monofractive, heavy sands with a high content of dust fraction, which chemical composition is dominated by oxides of iron, silicon and aluminum. This characteristic of the wastes has allowed us to outline possible ways of how to use them: in ceramic items production as thinning agents and fluxing agents, in Portland cement production as a correcting iron-containing agent, as a mortar filler, including special mortars, as a building materials volumetric staining pigment, etc.

  4. Effect of ferrous metal presence on lead leaching in municipal waste incineration bottom ashes.

    Science.gov (United States)

    Oehmig, Wesley N; Roessler, Justin G; Zhang, Jianye; Townsend, Timothy G

    2015-01-01

    The recovery of ferrous and non-ferrous metals from waste to energy (WTE) ash continues to advance as the sale of removed metals improves the economics of waste combustion. Published literature suggests that Fe and Fe oxides play a role in suppressing Pb leaching in the Toxicity Characteristic Leaching Procedure (TCLP); further removal of ferrous metals from WTE ashes may facilitate higher Pb leaching under the TCLP. Eight WTE bottom ash size-fractions, from three facilities, were evaluated to assess the effect of metallic Fe addition and ferrous metal removal on TCLP leaching. Metallic Fe addition was demonstrated to reduce Pb leaching; the removal of ferrous metals by magnet resulted in a decrease in total available Pb (mg/kg) in most ash samples, yet Pb leachability increased in 5 of 6 ash samples. The research points to two chemical mechanisms to explain these results: redox interactions between Pb and Fe and the sorption of soluble Pb onto Fe oxide surfaces, as well as the effect of the leachate pH before and after metals recovery. The findings presented here indicate that generators, processors, and regulators of ash should be aware of the impact ferrous metal removal may have on Pb leaching, as a substantial increase in leaching may have significant implications regarding the management of WTE ashes. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Absorbtion Activity of Cassava Peel (Manihot utilissima as Chromium (VI Metal Biosorbent in Electroplating Waste

    Directory of Open Access Journals (Sweden)

    Iin Candrawati

    2017-05-01

    Full Text Available Electroplating is a process of metal veneering with another metal using the electric energy. The water waste of electroplating industry contains many kinds of heavy metal ions, especially chromium (Cr6+ which might cause pollutions if it's not processed and it presents above the threshold allowed . The use of cellulose can be a solution, because it has the functional groups which form bonding with the metal ions. Cassava peel is one of the sources of cellulose which contains 80-85% of cellulose. This proves that cassava peel (Manihot utilissimaI has the potential as the heavy metal biosorbent of chromium metal in electroplating waste. The methodology of the research is conducted in a series including analysis of heavy metal concentrations of chromium (VI in electroplating waste, biosorption treatment of cassava peel (Manihot utilissimaI biosorbent activated by HNO3 1.5 M in electroplating waste with batch method, and analysis of heavy metal concentrations of chromium (VI in electroplating waste after biosorbtion process. Variation of biosorbent’s mass are (0.1, 0.2, 0.3, 0.4, 0.5 grams, and variation of biosorbent’s contact time are (10, 20, 30, 40, 50 minutes. The result of the AAS (Atomic Absorbtion Spectrophotometry shows that the level of total chromium in electroplating waste reaches 2.0777 ± 0.2785 ppm, so the chromium test solution used in this research is 2 ppm to know the optimum conditions of % chromium (VI absorbed with variation of mass and contact time. From the results of this research, the optimum mass and contact time of cassava peel biosorbent activated by HNO3 1.5 M in % chromium (VI absorbed are 0.1 gram and 40 minute. Finally, the optimum mass and contact time of cassava peel biosorbent activated by HNO3 1.5 M is applied to electroplating waste. The average of % chromium absorbed in electroplating waste with the addition of cassava peel biosorbent activated by HNO3 1.5 M is 61.72%.

  6. Metal waste forms from the electrometallurgical treatment of spent nuclear fuel

    International Nuclear Information System (INIS)

    Abraham, D.P.; McDeavitt, S.M.; Park, J.

    1996-01-01

    Stainless steel-zirconium alloys are being developed for the disposal of radioactive metal isotopes isolated using an electrometallurgical treatment technique to treat spent nuclear fuel. The nominal waste forms are stainless steel-15 wt% zirconium alloy and zirconium-8 wt% stainless steel alloy. These alloys are generated in yttria crucibles by melting the starting materials at 1,600 C under an argon atmosphere. This paper discusses the microstructures, corrosion and mechanical test results, and thermophysical properties of the metal waste form alloys

  7. Inorganic particulates in removal of toxic heavy metal ions: Part-X. removal behaviour of aluminum hydroxide for Hg(II) - a radiotracer study

    International Nuclear Information System (INIS)

    Mishra, S.P.; Tiwari, Diwakar; Prasad, S.K.; Dubey, R.S.; Mishra, Manisha

    2006-01-01

    The present paper deals with a study on the removal behaviour of amorphous-type aluminum hydroxide for Hg(II) at micro to tracer level concentrations from aqueous solutions by employing the radiotracer technique. The solid/solution interface study was carried out for various physico-chemical parameters, e.g., effect of concentration, temperature and pH. The effect of the presence of several added cations/anions towards its removal behaviour was also assessed

  8. Decomposition Mechanism and Decomposition Promoting Factors of Waste Hard Metal for Zinc Decomposition Process (ZDP)

    Energy Technology Data Exchange (ETDEWEB)

    Pee, J H; Kim, Y J; Kim, J Y; Cho, W S; Kim, K J [Whiteware Ceramic Center, KICET (Korea, Republic of); Seong, N E, E-mail: pee@kicet.re.kr [Recytech Korea Co., Ltd. (Korea, Republic of)

    2011-10-29

    Decomposition promoting factors and decomposition mechanism in the zinc decomposition process of waste hard metals which are composed mostly of tungsten carbide and cobalt were evaluated. Zinc volatility amount was suppressed and zinc steam pressure was produced in the reaction graphite crucible inside an electric furnace for ZDP. Reaction was done for 2 hrs at 650 deg. C, which 100% decomposed the waste hard metals that were over 30 mm thick. As for the separation-decomposition of waste hard metals, zinc melted alloy formed a liquid composed of a mixture of {gamma}-{beta}1 phase from the cobalt binder layer (reaction interface). The volume of reacted zone was expanded and the waste hard metal layer was decomposed-separated horizontally from the hard metal. Zinc used in the ZDP process was almost completely removed-collected by decantation and volatilization-collection process at 1000 deg. C. The small amount of zinc remaining in the tungsten carbide-cobalt powder which was completely decomposed was fully removed by using phosphate solution which had a slow cobalt dissolution speed.

  9. Children with health impairments by heavy metals in an e-waste recycling area.

    Science.gov (United States)

    Zeng, Xiang; Xu, Xijin; Boezen, H Marike; Huo, Xia

    2016-04-01

    E-waste recycling has become a global environmental health issue. Pernicious chemicals escape into the environment due to informal and nonstandard e-waste recycling activities involving manual dismantling, open burning to recover heavy metals and open dumping of residual fractions. Heavy metals derived from electronic waste (e-waste), such as, lead (Pb), cadmium (Cd), chromium (Cr), manganese (Mn), nickel (Ni), mercury (Hg), arsenic (As), copper (Cu), zinc (Zn), aluminum (Al) and cobalt (Co), differ in their chemical composition, reaction properties, distribution, metabolism, excretion and biological transmission. Our previous studies showed that heavy metal exposure have adverse effects on children's health including lower birth weight, lower anogenital distance, lower Apgar scores, lower current weight, lower lung function, lower hepatitis B surface antibody levels, higher prevalence of attention-deficit/hyperactivity disorder, and higher DNA and chromosome damage. Heavy metals influence a number of diverse systems and organs, resulting in both acute and chronic effects on children's health, ranging from minor upper respiratory irritation to chronic respiratory, cardiovascular, nervous, urinary and reproductive disease, as well as aggravation of pre-existing symptoms and disease. These effects of heavy metals on children's health are briefly discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Direct conversion of plutonium metal, scrap, residue, and transuranic waste to glass

    International Nuclear Information System (INIS)

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.; Malling, J.F.; Rudolph, J.

    1995-01-01

    A method for the direct conversion of metals, ceramics, organics, and amorphous solids to borosilicate glass has been invented. The process is called the Glass Material Oxidation and Dissolution System (GMODS). Traditional glass-making processes can convert only oxide materials to glass. However, many wastes contain complex mixtures of metals, ceramics, organics, and amorphous solids. Conversion of such mixtures to oxides followed by their conversion to glass is often impractical. GMODS may create a practical method to convert such mixtures to glass. Plutonium-containing materials (PCMS) exist in many forms, including metals, ceramics, organics, amorphous solids, and mixtures thereof. These PCMs vary from plutonium metal to filters made of metal, organic binders, and glass fibers. For storage and/or disposal of PCMS, it is desirable to convert PCMs to borosilicate glass. Borosilicate glass is the preferred repository waste form for high-level waste (HLW) because of its properties. PCMs converted to a transuranic borosilicate homogeneous glass would easily pass all waste acceptance and storage criteria. Conversion of PCMs to a glass would also simplify safeguards by conversion of heterogeneous PCMs to homogeneous glass. Thermodynamic calculations and proof-of-principle experiments on the GMODS process with cerium (plutonium surrogate), uranium, stainless steel, aluminum, Zircaloy-2, and carbon were successfully conducted. Initial analysis has identified potential flowsheets and equipment. Major unknowns remain, but the preliminary data suggests that GMODS may be a major new treatment option for PCMs

  11. Phytomining of valuable metals from waste incineration residues using hyperaccumulator plants

    Science.gov (United States)

    Rosenkranz, Theresa; Kisser, Johannes; Gattringer, Heinz; Iordanopoulos-Kisser, Monika; Puschenreiter, Markus

    2015-04-01

    Worldwide the availability of primary sources of certain economically important metals is decreasing, resulting in high supply risks and increasing prices for this materials. Therefore, an alternative way of retrieving these high valuable technical metals is the recycling and use of anthropogenic secondary sources, such as waste incineration residues. Phytomining offers an environmentally sound and cheap technology to recover such metals from secondary sources. Thus, the aim of our research work is to investigate the potential of phytomining from waste incineration slags by growing metal hyperaccumulating plants on this substrates and use the metal enriched biomass as a bio-ore. As a first stage, material from Vienna's waste incineration plants was sampled and analyzed. Residues from municipal wastes as well as residues from hazardous waste incineration and sewage sludge incineration were analyzed. In general, the slags can be characterized by a very high pH, high salinity and high heavy metal concentrations. Our work is targeting the so-called critical raw materials defined by the European Commission in 2014. Thus, the target metal species in our project are amongst others cobalt, chromium, antimony, tungsten, gallium, nickel and selected rare earth elements. This elements are present in the slags at moderate to low concentrations. In order to optimize the substrate for plant growth the high pH and salt content as well as the low nitrogen content in the slags need to be controlled. Thus, different combinations of amendments, mainly from the waste industry, as well as different acidifying agents were tested for conditioning the substrate. Washing the slags with diluted nitric acid turned out to be effective for lowering the pH. The acid treated substrate in combination with material from mechanical biological waste treatment and biochar, is currently under investigation in a greenhouse pot experiment. The experimental setup consists of a full factorial design

  12. Inorganic particulates in removal of toxic heavy metal ions. Part 10. Removal behavior of aluminum hydroxide for Hg(II). A radiotracer study

    International Nuclear Information System (INIS)

    Mishra, S.P.; Tiwari, D.; Prasad, S.K.; Dubey, R.S.; Manisha Mishra

    2007-01-01

    The removal behavior of amorphous aluminum hydroxide for Hg(II) ions from aqueous solutions was investigated by employing a radiotracer technique at micro down to trace level concentrations. The batch type experiments were performed to obtain various physico-chemical parameters, viz., effect of sorptive concentration, temperature and pH. It was observed that the increase in sorptive concentration (from 1 x 10 -8 to 1 x 10 -2 mol x dm -3 ), temperature (from 303 to 333 K) and pH (from 3.4 to 10.3) apparently favored the uptake of Hg(II) by this solid. Similarly, the presence of anions (six fold) viz., oxalate, phosphate, glycine and EDTA also enhanced the uptake behavior of aluminum hydroxide for Hg(II). Whereas, the added cations viz., Na + , K + , Ba 2+ , Sr 2+ , Mg 2+ , Cd 2+ and Fe 3+ more or less suppressed the removal behavior of the adsorbent. Further, the adsorption process followed the classical Freundlich adsorption isotherm and deductions of various thermodynamic data revealed that the uptake of Hg(II) on aluminum hydroxide followed the ion-exchange type mechanism and thermodynamically it was found to be endothermic in nature. (author)

  13. Analysis of physical composition and heavy metals pollution of municipal solid waste (MSW) in Beijing

    Science.gov (United States)

    Zhang, H. B.; Zhang, H. Y.; Wang, G. Q.; Bai, X. J.

    2018-03-01

    By using on-site sampling and physical-chemical analysis, the physical composition and the contents of heavy metals in Beijing MSW were researched. The result showed that the main components of MSW in Beijing are mainly kitchen waste, the average content of kitchen waste are more than 60% and 50% in summer and in winter, respectively. The pollution of Cu, Hg and Cr are all more serious for MSW in Haidian and Dongcheng district. The heavy metal pollution of MSW in summer is higher than that in winter in Beijing. Seasonal impacts should be taken into consideration when dealing with MSW. The content of heavy metals in MSW exceeded the background value of soil in Haidian and Dongcheng districts. In order to reduce heavy metal pollution, the MSW should be separated collection and treated.

  14. Implementation of Statistical Methods and SWOT Analysis for Evaluation of Metal Waste Management in Engineering Company

    Directory of Open Access Journals (Sweden)

    Záhorská Renáta

    2016-12-01

    Full Text Available This paper presents the results of the waste management research in a selected engineering company RIBE Slovakia, k. s., Nitra factory. Within of its manufacturing programme, the mentioned factory uses wide range of the manufacturing technologies (cutting operations, metal cold-forming, thread rolling, metal surface finishing, automatic sorting, metrology, assembly, with the aim to produce the final products – connecting components (fasteners delivered to many industrial fields (agricultural machinery manufacturers, car industry, etc.. There were obtained data characterizing production technologies and the range of manufactured products. The key attention is paid to the classification of waste produced by engineering production and to waste management within the company. Within the research, there were obtained data characterizing the time course of production of various waste types and these data were evaluated by means of statistical method using STATGRAPHICS. Based on the application of SWOT analysis, there is objectively assessed the waste management in the company in terms of strengths and weaknesses, as well as determination of the opportunities and potential threats. Results obtained by the SWOT analysis application have allowed to come to conclusion that the company RIBE Slovakia, k. s., Nitra factory has well organized waste management system. The fact that the waste management system is incorporated into the company management system can be considered as an advantage.

  15. Study on the behavior of heavy metals during thermal treatment of municipal solid waste (MSW) components.

    Science.gov (United States)

    Yu, Jie; Sun, Lushi; Wang, Ben; Qiao, Yu; Xiang, Jun; Hu, Song; Yao, Hong

    2016-01-01

    Laboratory experiments were conducted to investigate the volatilization behavior of heavy metals during pyrolysis and combustion of municipal solid waste (MSW) components at different heating rates and temperatures. The waste fractions comprised waste paper (Paper), disposable chopstick (DC), garbage bag (GB), PVC plastic (PVC), and waste tire (Tire). Generally, the release trend of heavy metals from all MSW fractions in rapid-heating combustion was superior to that in low-heating combustion. Due to the different characteristics of MSW fractions, the behavior of heavy metals varied. Cd exhibited higher volatility than the rest of heavy metals. For Paper, DC, and PVC, the vaporization of Cd can reach as high as 75% at 500 °C in the rapid-heating combustion due to violent combustion, whereas a gradual increase was observed for Tire and GB. Zn and Pb showed a moderate volatilization in rapid-heating combustion, but their volatilities were depressed in slow-heating combustion. During thermal treatment, the additives such as kaolin and calcium can react or adsorb Pb and Zn forming stable metal compounds, thus decreasing their volatilities. The formation of stable compounds can be strengthened in slow-heating combustion. The volatility of Cu was comparatively low in both high and slow-heating combustion partially due to the existence of Al, Si, or Fe in residuals. Generally, in the reducing atmosphere, the volatility of Cd, Pb, and Zn was accelerated for Paper, DC, GB, and Tire due to the formation of elemental metal vapor. TG analysis also showed the reduction of metal oxides by chars forming elemental metal vapor. Cu2S was the dominant Cu species in reducing atmosphere below 900 °C, which was responsible for the low volatility of Cu. The addition of PVC in wastes may enhance the release of heavy metals, while GB and Tire may play an opposite effect. In controlling heavy metal emission, aluminosilicate- and calcium-based sorbents can be co-treated with fuels. Moreover

  16. Mitigation of Hydrogen Gas Generation from the Reaction of Uranium Metal with Water in K Basin Sludge and Sludge Waste Forms

    Energy Technology Data Exchange (ETDEWEB)

    Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

    2011-06-08

    Prior laboratory testing identified sodium nitrate and nitrite to be the most promising agents to minimize hydrogen generation from uranium metal aqueous corrosion in Hanford Site K Basin sludge. Of the two, nitrate was determined to be better because of higher chemical capacity, lower toxicity, more reliable efficacy, and fewer side reactions than nitrite. The present lab tests were run to determine if nitrate’s beneficial effects to lower H2 generation in simulated and genuine sludge continued for simulated sludge mixed with agents to immobilize water to help meet the Waste Isolation Pilot Plant (WIPP) waste acceptance drainable liquid criterion. Tests were run at ~60°C, 80°C, and 95°C using near spherical high-purity uranium metal beads and simulated sludge to emulate uranium-rich KW containerized sludge currently residing in engineered containers KW-210 and KW-220. Immobilization agents tested were Portland cement (PC), a commercial blend of PC with sepiolite clay (Aquaset II H), granulated sepiolite clay (Aquaset II G), and sepiolite clay powder (Aquaset II). In all cases except tests with Aquaset II G, the simulated sludge was mixed intimately with the immobilization agent before testing commenced. For the granulated Aquaset II G clay was added to the top of the settled sludge/solution mixture according to manufacturer application directions. The gas volumes and compositions, uranium metal corrosion mass losses, and nitrite, ammonia, and hydroxide concentrations in the interstitial solutions were measured. Uranium metal corrosion rates were compared with rates forecast from the known uranium metal anoxic water corrosion rate law. The ratios of the forecast to the observed rates were calculated to find the corrosion rate attenuation factors. Hydrogen quantities also were measured and compared with quantities expected based on non-attenuated H2 generation at the full forecast anoxic corrosion rate to arrive at H2 attenuation factors. The uranium metal

  17. Mitigation of Hydrogen Gas Generation from the Reaction of Uranium Metal with Water in K Basin Sludge and Sludge Waste Forms

    International Nuclear Information System (INIS)

    Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

    2011-01-01

    Prior laboratory testing identified sodium nitrate and nitrite to be the most promising agents to minimize hydrogen generation from uranium metal aqueous corrosion in Hanford Site K Basin sludge. Of the two, nitrate was determined to be better because of higher chemical capacity, lower toxicity, more reliable efficacy, and fewer side reactions than nitrite. The present lab tests were run to determine if nitrate's beneficial effects to lower H2 generation in simulated and genuine sludge continued for simulated sludge mixed with agents to immobilize water to help meet the Waste Isolation Pilot Plant (WIPP) waste acceptance drainable liquid criterion. Tests were run at ∼60 C, 80 C, and 95 C using near spherical high-purity uranium metal beads and simulated sludge to emulate uranium-rich KW containerized sludge currently residing in engineered containers KW-210 and KW-220. Immobilization agents tested were Portland cement (PC), a commercial blend of PC with sepiolite clay (Aquaset II H), granulated sepiolite clay (Aquaset II G), and sepiolite clay powder (Aquaset II). In all cases except tests with Aquaset II G, the simulated sludge was mixed intimately with the immobilization agent before testing commenced. For the granulated Aquaset II G clay was added to the top of the settled sludge/solution mixture according to manufacturer application directions. The gas volumes and compositions, uranium metal corrosion mass losses, and nitrite, ammonia, and hydroxide concentrations in the interstitial solutions were measured. Uranium metal corrosion rates were compared with rates forecast from the known uranium metal anoxic water corrosion rate law. The ratios of the forecast to the observed rates were calculated to find the corrosion rate attenuation factors. Hydrogen quantities also were measured and compared with quantities expected based on non-attenuated H2 generation at the full forecast anoxic corrosion rate to arrive at H2 attenuation factors. The uranium metal

  18. Impact of the Municipal Solid Waste Łubna Landfill on Environmental Pollution by Heavy Metals

    Directory of Open Access Journals (Sweden)

    Barbara Gworek

    2016-10-01

    Full Text Available Landfills have been identified as potential sources of heavy metal pollution of the environment. The municipal solid waste Łubna landfill is one of the largest landfills in Poland. Its impact on heavy metal pollution (Cd, Pb, Zn, Cu, and Cr of groundwater, soil and plants has been thoroughly evaluated. Elevated levels of contamination have not been recorded in the vicinity of the landfill. The concentrations of heavy metals in soil from the vicinity of the landfill were similar to the geochemical background levels for the forest and farming soils of central Poland. The concentrations of heavy metals in European goldenrod (Solidago virgaurea L. and grasses (Poaceae did not exceed the baseline concentrations and did not indicate environmental pollution by heavy metals. The levels of the metal concentration in groundwater did not exceed the standards established for water intended for consumption.

  19. Fresh organic matter of municipal solid waste enhances phytoextraction of heavy metals from contaminated soil

    International Nuclear Information System (INIS)

    Salati, S.; Quadri, G.; Tambone, F.; Adani, F.

    2010-01-01

    In this study, the ability of the organic fraction of municipal solid wastes (OFMSW) to enhance heavy metal uptake of maize shoots compared with ethylenediamine disuccinic acid (EDDS) was tested on soil contaminated with heavy metals. Soils treated with OFMSW and EDDS significantly increased the concentration of heavy metals in maize shoots (increments of 302%, 66%, 184%, 169%, and 23% for Cr, Cu, Ni, Zn, and Pb with respect to the control and increments of 933%, 482%, 928%, 428%, and 5551% for soils treated with OFMSW and EDDS, respectively). In soil treated with OFMSW, metal uptake was favored because of the high presence of dissolved organic matter (DOM) (41.6x than soil control) that exhibited ligand properties because of the high presence of carboxylic acids. Because of the toxic effect of EDDS on maize plants, soil treated with OFMSW achieved the highest extraction of total heavy metals. - Organic fraction of MSW affects the bioavailability of heavy metals in soil.

  20. status evaluation of heavy metals in waste disposal sites of ...

    African Journals Online (AJOL)

    PROF EKWUEME

    samples were also collected through purposive sampling method within the Champion Breweries and Plasto Crown Company waste dump sites. (Figure 1) with the aid of a soil auger and put separately in labeled steriled containers. The same samples in the control site were equally collected. They were transported to the.

  1. [Correlation of Persistent Free Radicals, PCDD/Fs and Metals in Waste Incineration Fly Ash].

    Science.gov (United States)

    Wang, Tian-jiao; Chen, Tong; Zhan, Ming-xiu; Guo, Ying; Li, Xiao-dong

    2016-03-15

    Environmentally persistent free radicals (EPFRs) are relatively highly stable and found in the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Recent studies have concentrated on model dioxin formation reactions and there are few studies on actual waste incineration fly ash. In order to study EPFRs and the correlation with dioxins and heavy metals in waste incineration fly ash, the spins of EPFRs, concentration of PCDD/Fs and metals in samples from 6 different waste incinerators were detected. The medical waste incineration fly ash from Tianjin, municipal solid waste incineration fly ash from Jiangxi Province, black carbon and slag from municipal solid waste incinerator in Lanxi, Zhejiang Province, all contained EPFRs. Above all the signal in Tianjin sample was the strongest. Hydroxyl radicals, carbon-center radicals and semiquinone radicals were detected. Compared with other samples, Jiangxi fly ash had the highest toxic equivalent quantity (TEQ) of dioxins, up to 7.229 4 ng · g⁻¹. However, the dioxin concentration in the Tianjin sample containing the strongest EPFR signals was only 0.092 8 ng · g⁻¹. There was perhaps little direct numeric link between EPFRs and PCDD/Fs. But the spins of EPFRs in samples presented an increasing trend as the metal contents increased, especially with Al, Fe, Zn. The signal strength of radicals was purposed to be related to the metal contents. The concentration of Zn (0.813 7% ) in the Tianjin sample was the highest and this sample contained much more spins of oxygen-center radicals. We could presume the metal Zn had a greater effect on the formation of EPFRs, and was easier to induce the formation of radicals with a longer half-life period.

  2. Effect of heavy metals on earthworm activities during vermicomposting of municipal solid waste.

    Science.gov (United States)

    Kumar, Sunil; Sharma, Vishal; Bhoyar, R V; Bhattacharyya, J K; Chakrabarti, Tapan

    2008-02-01

    The effect of heavy metals on the activities of earthworm species Eudrillus eugineae was studied during vermicomposting of municipal solid waste (MSW) spiked with heavy metals. The activities of earthworms, in terms of growth and biomass production and number of cocoons produced, were monitored periodically, and the concentration of heavy metals in earthworms and substrates was determined at definite intervals. Laboratory-scale experiments were performed by mixing individual heavy metals in MSW. Copper, cadmium, chromium, lead, and zinc were selected for the study. The study concludes that heavy metals tend to accumulate in the body of earthworms; hence, the inherent concentration of heavy metals in the substrate before vermicomposting must be considered in view of composting of MSW and its application to soil. It was observed that copper and cadmium were toxic for the worms at 1.5 and 0.1 g/kg of the waste, respectively. The studies also suggest that earthworms are susceptible to the free form of heavy metals. Cadmium is the most toxic metal, followed by copper. Based on the investigation and observation, it was also found that earthworms should be separated from castings before the use of castings in soil amendments.

  3. Metal concentrations and distribution in paint waste generated during bridge rehabilitation in New York State.

    Science.gov (United States)

    Shu, Zhan; Axe, Lisa; Jahan, Kauser; Ramanujachary, Kandalam V; Kochersberger, Carl

    2015-09-01

    Between 1950 and 1980, lead and chromium along with other metals have been used in paint coatings to protect bridges from corrosion. In New York State with 4500 bridges in 11 Regions 2385 of the bridges have been rehabilitated and subsequently repainted after 1989 when commercial use of lead based paint was prohibited. The purpose of this research was to address the concentration and distribution of trace metals in the paint waste generated during bridge rehabilitation. Using hypothesis testing and stratified sampling theory, a representative sample size of 24 bridges from across the state was selected that resulted in 117 paint waste samples. Field portable X-ray fluorescence (FP-XRF) analysis revealed metal concentrations ranged from 5 to 168,090 mg kg(-1) for Pb, 49,367 to 799,210 mg kg(-1) for Fe, and 27 to 425,510 mg kg(-1) for Zn. Eighty percent of the samples exhibited lead concentrations greater than 5000 mg kg(-1). The elevated iron concentrations may be attributed to the application of steel grit as an abrasive blasting material routinely used by state Departments of Transportation in the paint removal process. Other metals including Ba and Cr were observed in the paint waste as well. As a result of the paint formulation, metals were found to be associated in the paint waste (Pb correlated with Cr (r=0.85)). The elevated metal concentrations observed raises concern over the potential impact of leaching from this waste stream. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Method of processing radioactive liquid wastes

    International Nuclear Information System (INIS)

    Shikata, Eiji; Nakamura, Haruto; Miyazaki, Kazuhide; Sato, Toshikazu; Ishii, Masato.

    1980-01-01

    Purpose: To effectively and economically eliminate toxic radioactive nuclides contained at an extremely low concentration of about 10 -6 - 10 -10 ppm in radioactive liquid wastes. Method: Radioactive liquid wastes are subjected to DC current electrolysis using aluminum or aluminum alloy as an anode. Toxic nuclides contained at an extremely low concentration in the liquid wastes are adsorbed onto aluminum hydroxide having intense activity formed from aluminum ions leached out from the anode and combined with hydroxyl ions. The process can effectively separate to remove the following radioactive nuclides: Cr-51, Co-53, Co-60 (heavy metal elements), La-140, Ce-143 (Lanthanoide elements), Pu-239, Np-239 (actinoid elements). (Ikeda, J.)

  5. Closing the Phosphorus Loop by Recovering Phosphorus From Waste Streams With Layered Double Hydroxide Nanocomposites and Converting the Product into an Efficient Fertilizer

    Science.gov (United States)

    Yan, H.; Shih, K.

    2015-12-01

    Phosphorus (P) recovery has been frequently discussed in recent decades due to the uncertain availability and uneven distribution of global phosphate rock reserves. Sorption technology is increasingly considered as a reliable, efficient and environmentally friendly P removal method from aqueous solution. In this study, a series of Mg-Al-based layered double hydroxide nanocomposites and their corresponding calcined products were fabricated and applied as phosphate adsorbents. The prepared samples were with average size at ~50 nm and self-assembled into larger particles in irregular shapes. The results of batch adsorption experiments demonstrated that calcination significantly enhanced the adsorption ability of LDHs for phosphorus, and the maximum adsorption capacity of calcined Mg-Al-LDH was as high as 100.7 mg-P/g. Furthermore, incorporation of Zr4+ and La3+ into LDH materials increases the sorption selectivity as well as sorption amount of phosphorus in LDHs, which was confirmed by experiments operated in synthetic human urine. For the first time ammonia (NH4OH) and potassium hydroxide (KOH) solutions were employed to desorb the P-loaded LDH. Identification of solids derived from two eluting solutions showed that struvite (MgNH4PO4•6H2O, MAP) was precipitated in ammonia solution while most phosphate was desorbed into liquid phase in KOH system without crystallization of potassium struvite (MgKPO4•6H2O) due to its higher solubility. Quantitative X-ray diffraction technique was used to determine struvite contents in obtained solids and the results revealed that ~ 30% of adsorbed P was transferred into struvite form in the sample extracted by 0.5M NH4OH. Leaching tests suggested that the phosphorus releasing kinetics of ammonia treated LDH was comparable to that of pure struvite product, indicating that postsorption Mg-Al-LDH desorbed with ammonia could serve as a slow-releasing fertilizer in agriculture (see Figure 1).

  6. Economic evaluation of an electrochemical process for the recovery of metals from electronic waste.

    Science.gov (United States)

    Diaz, Luis A; Lister, Tedd E

    2018-04-01

    As the market of electronic devices continues to evolve, the waste stream generated from antiquated technology is increasingly view as an alternative to substitute primary sources of critical a value metals. Nevertheless, the sustainable recovery of materials can only be achieved by environmentally friendly processes that are economically competitive with the extraction from mineral ores. Hence, This paper presents the techno-economic assessment for a comprehensive process for the recovery of metals and critical materials from e-waste, which is based in an electrochemical recovery (ER) technology. Economic comparison is performed with the treatment of e-waste via smelting, which is currently the primary route for recycling metals from electronics. Results indicate that the electrochemical recovery process is a competitive alternative for the recovery of value from electronic waste when compared with the traditional black Cu smelting process. A significantly lower capital investment, 2.9 kg e-waste per dollar of capital investment, can be achieved with the ER process vs. 1.3 kg per dollar in the black Cu smelting process. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Pressure leaching of metals from waste printed circuit boards using sulfuric acid

    Science.gov (United States)

    Jha, Manis K.; Lee, Jae-Chun; Kumari, Archana; Choubey, Pankaj K.; Kumar, Vinay; Jeong, Jinki

    2011-08-01

    Printed circuit boards (PCBs) are essential components of electronic equipments which contain various metallic values. This paper reports a hydrometallurgical recycling process for waste PCBs, which consists of the novel pretreatment consisting of organic swelling of PCBs followed by sulfuric acid leaching of metals from waste PCBs. To recycle the waste PCBs, experiments were carried out for the recovery of copper from the crushed and organic swelled materials of waste PCBs using sulfuric acid leaching in presence of hydrogen peroxide under atmospheric and pressure condition. The leaching of PCBs at 90°C, pulp density 100 g/L under atmospheric condition, using 6M sulfuric acid resulted in the dissolution of a minor amount of copper due to the presence of plastic coating on the surface of metallic layers. On the other hand, when the liberated metal sheets from organic swelled PCBs were treated with dilute sulfuric acid of concentration 2M along with hydrogen peroxide in an autoclave under oxygen atmosphere, the percentage recovery of copper was found to increase from 59.63% to 97.01% with an increase in hydrogen peroxide concentration from 5 to 15% (v/v) keeping constant pulp density 30 g/L.

  8. Autoclave reduction of jarosites and other metal sulfates : a new approach to major waste problems

    NARCIS (Netherlands)

    Hage, J.L.T.

    1999-01-01

    Industrial jarosite is a waste product of the zinc industry. It is considered a serious environmental problem, due to the quantity produced and the mobile hazardous metals it contains. Over 50 million tons are already stored worldwide. The jarosite sludge autoclave treatment process described in

  9. Devoluming method and device for radioactive metal wastes containing zirconium alloy

    International Nuclear Information System (INIS)

    Komatsu, Masahiko; Wada, Ryutaro.

    1996-01-01

    The present invention concerns a method of sealing radioactive metal wastes in a capsule and compressing the capsule for devoluming treatment. The method comprises a step of carrying radioactive metal wastes into a sealed chamber having a capacity somewhat greater than that of the capsule, a deaerating step of sucking the air in the sealed chamber to attain a substantially vacuum state, a compression-devoluming step of compression-devoluming the capsule by reducing the volume of the sealed chamber and a transporting step of transporting the devolumed capsule from the sealed chamber. The sealed chamber to which the capsule incorporated with radioactive metal wastes containing a zirconium alloy is carried is then deaerated into a substantially vacuum state. Even if ignitable powdery dusts are generated from the radioactive metal wastes crushed by compression-devoluming of the capsule in the succeeding compression-devoluming step, since the air necessary for ignition is not present, ignition of the powdery dusts is prevented. Alternatively, since the inside of the sealed chamber is filled with an inert gas, ignition of the powdery dusts can effectively be prevented. (N.H.)

  10. Removal of heavy metal contamination from peanut skin extracts by waste biomass adsorption

    Science.gov (United States)

    Polyphenols are a rapidly increasing portion of the nutraceutical and functional food marketplace. Peanut skins are a waste product which have potential as a low-cost source of polyphenols. Extraction and concentration of peanut skin extracts can cause normally innocuous levels of the heavy metal co...

  11. New Engineering Solutions in Creation of Mini-BOF for Metallic Waste Recycling

    Science.gov (United States)

    Eronko, S. P.; Gorbatyuk, S. M.; Oshovskaya, E. V.; Starodubtsev, B. I.

    2017-12-01

    New engineering solutions used in design of the mini melting unit capable of recycling industrial and domestic metallic waste with high content of harmful impurities are provided. High efficiency of the process technology implemented with its use is achieved due to the possibility of the heat and mass transfer intensification in the molten metal bath, controlled charge into it of large amounts of reagents in lumps and in fines, and cut-off of remaining process slag during metal tapping into the teeming ladle.

  12. New data on mineral forms of rare metals in phosphogypsum wastes

    Science.gov (United States)

    Samonov, A. E.

    2011-09-01

    Phosphogypsum is an industrial waste of the processing of Khibiny apatite concentrate into chemical fertilizers by sulfurous technology. This is a valuable and promising technogenous rare-metal feedstock. The samples of fresh and old phosphogypsum were studied using precision physical techniques of analytical electron microscopy and X-ray spectral microanalysis. These studies allowed the discovery of new and unusual mineral compositions including strontium and rare earth metals in mineral fractions of phosphogypsum. The appearance of a new generation of technogenous rare-metal raw material permits us to characterize the prospects of its industrial use and to develop nonwaste technologies of its complex treatment.

  13. Some potential strategies for the treatment of waste uranium metal and uranium alloys

    International Nuclear Information System (INIS)

    Burns, C.J.; Frankcom, T.M.; Gordon, P.L.; Sauer, N.N.

    1993-01-01

    Large quantities of uranium metal chips and turnings stored throughout the DOE Complex represent a potential hazard, due to the reactivity of this material toward air and water. Methods are being sought to mitigate this by conversion of the metal, via room temperature solutions routes, to a more inert oxide form. In addition, the recycling of uranium and concomitant recovery of alloying metals is a desirable goal. The emphasis of the authors' research is to explore a variety of oxidation and reduction pathways for uranium and its compounds, and to investigate how these reactions might be applied to the treatment of bulk wastes

  14. Heavy metal contamination of surface soil in electronic waste dismantling area: site investigation and source-apportionment analysis.

    Science.gov (United States)

    Jinhui Li; Huabo Duan; Pixing Shi

    2011-07-01

    The dismantling and disposal of electronic waste (e-waste) in developing countries is causing increasing concern because of its impacts on the environment and risks to human health. Heavy-metal concentrations in the surface soils of Guiyu (Guangdong Province, China) were monitored to determine the status of heavy-metal contamination on e-waste dismantling area with a more than 20 years history. Two metalloids and nine metals were selected for investigation. This paper also attempts to compare the data among a variety of e-waste dismantling areas, after reviewing a number of heavy-metal contamination-related studies in such areas in China over the past decade. In addition, source apportionment of heavy metal in the surface soil of these areas has been analysed. Both the MSW open-burning sites probably contained invaluable e-waste and abandoned sites formerly involved in informal recycling activities are the new sources of soil-based environmental pollution in Guiyu. Although printed circuit board waste is thought to be the main source of heavy-metal emissions during e-waste processing, requirement is necessary to soundly manage the plastic separated from e-waste, which mostly contains heavy metals and other toxic substances.

  15. Experimental design and process analysis for acidic leaching of metal-rich glass wastes.

    Science.gov (United States)

    Tuncuk, A; Ciftci, H; Akcil, A; Ognyanova, A; Vegliò, F

    2010-05-01

    The removal of iron, titanium and aluminium from colourless and green waste glasses has been studied under various experimental conditions in order to optimize the process parameters and to decrease the metal content in the waste glass by acidic leaching. Statistical design of experiments and ANOVA (analysis of variance) were performed in order to determine the main effects and interactions between the investigated factors (sample ratio, acid concentration, temperature and leaching time). A full factorial experiment was performed by sulphuric acid leaching of glass for metal removal. After treating, the iron content was 530 ppm, corresponding to 1880 ppm initial concentration of Fe(2)O(3) in the original colourless sample. This result is achieved using 1M H(2)SO( 4) and 30% sample ratio at 90(o)C leaching temperature for 2 hours. The iron content in the green waste glass sample was reduced from 3350 ppm initial concentration to 2470 ppm after treating.

  16. Development of Ceramic Coating on Metal Substrate using Industrial Waste and Ore Minerals

    Science.gov (United States)

    Bhuyan, S. K.; Thiyagarajan, T. K.; Mishra, S. C.

    2017-02-01

    The technological advancement in modern era has a boon for enlightening human life; but also is a bane to produce a huge amount of (industrial) wastes, which is of great concern for utilization and not to create environmental threats viz. polution etc. In the present piece of research work, attempts have been made to utilize fly ash (wastes of thermal power plants) and along with alumina bearing ore i.e. bauxite, for developing plasma spray ceramic coatings on metals. Fly ash and with 10 and 20% bauxite addition is used to deposit plasma spray coatings on a metal substrate. The surface morphology of the coatings deposited at different power levels of plasma spraying investigated through SEM and EDS analysis. The coating thickness is measured. The porosity levels of the coatings are evaluated. The coating hardness isalso measured. This piece of research work will be beneficial for future development and use of industrial waste and ore minerals for high-valued applications.

  17. Sodium Hydroxide and Calcium Hydroxide Hybrid Oxygen Bleaching with System

    Science.gov (United States)

    Doelle, K.; Bajrami, B.

    2018-01-01

    This study investigates the replacement of sodium hydroxide in the oxygen bleaching stage using a hybrid system consisting of sodium hydroxide calcium hydroxide. Commercial Kraft pulping was studied using yellow pine Kraft pulp obtained from a company in the US. The impact of sodium hydroxide, calcium hydroxide hybrid system in regard to concentration, reaction time and temperature for Kraft pulp was evaluated. The sodium hydroxide and calcium hydroxide dosage was varied between 0% and 15% based on oven dry fiber content. The bleaching reaction time was varied between 0 and 180 minutes whereas the bleaching temperature ranged between 70 °C and 110 °C. The ability to bleach pulp was measured by determining the Kappa number. Optimum bleaching results for the hybrid system were achieved with 4% sodium hydroxide and 2% calcium hydroxide content. Beyond this, the ability to bleach pulp decreased.

  18. Iodine Sequestration Using Delafossites and Layered Hydroxides

    Energy Technology Data Exchange (ETDEWEB)

    J.D. Pless; J.B. Chwirka; J.L. Krumhansl

    2006-03-28

    The objective of this document is to report on early success for sequestering {sup 129}I. Sorption coefficients (K{sub d}) for I{sup -} and IO{sub 3}{sup -} onto delafossites, spinels and layered metal hydroxides were measured in order to compare their applicability for sequestering {sup 129}I. The studies were performed using a dilute fluid composition representative of groundwater indigenous to the Yucca mountain area. Delafossites generally exhibited relatively poor sorption coefficients (< 10{sup 1.7} mL/g). In contrast, the composition of the layered hydroxides significantly affects their ability to sorb I. Cu/Al and Cu/Cr layered hydroxide samples exhibit K{sub d}'s greater than 10{sup 3} mL/g for both I{sup -} and IO{sub 3}{sup -}.

  19. Leaching of gold, silver and accompanying metals from circuit boards (PCBs waste

    Directory of Open Access Journals (Sweden)

    Jana Ficeriová

    2011-12-01

    Full Text Available Au-Ag noble metal wastes represent a wide range of waste types and forms, with various accompanying metallic elements.The presented leaching strategy for Au-Ag contained in circuit boards (PCBs aims at gaining gold and silver in the metallic form.Application of the proposed ammonium thiosulphate leaching process for the treatment of the above mentioned Au-Ag containing wastesrepresents a practical, economic and at the same time an ecological solution. The ammonium thiosulphate based leaching of gold and silverfrom PCBs waste, using crushing as a pretreatment, was investigated. It was possible to achieve 98 % gold and 93 % silver recovery within48 hours of ammonium thiosulphate leaching. This type of leaching is a better leaching procedure for recovery of gold and silver from PCBwaste than the classical toxic cyanide leaching. 84 % Cu, 82 % Fe, 77 % Al, 76 % Zn, 70 % Ni, 90 % Pd, 88 % Pb and 83 % Sn recovery ofthe accompanying metals was achieved, using sulphuric acid with hydrogen peroxide, sodium chloride and aqua regia. A four steps leachingprocess gave a very satisfactory yield and a more rapid kinetics for all observed metals solubilization than other technologies.

  20. Metal waste forms from treatment of EBR-II spent fuel

    International Nuclear Information System (INIS)

    Abraham, D. P.

    1998-01-01

    Demonstration of Argonne National Laboratory's electrometallurgical treatment of spent nuclear fuel is currently being conducted on irradiated, metallic driver fuel and blanket fuel elements from the Experimental Breeder Reactor-II (EBR-II) in Idaho. The residual metallic material from the electrometallurgical treatment process is consolidated into an ingot, the metal waste form (MWF), by employing an induction furnace in a hot cell. Scanning electron microscopy (SEM) and chemical analyses have been performed on irradiated cladding hulls from the driver fuel, and on samples from the alloy ingots. This paper presents the microstructures of the radioactive ingots and compares them with observations on simulated waste forms prepared using non-irradiated material. These simulated waste forms have the baseline composition of stainless steel - 15 wt % zirconium (SS-15Zr). Additions of noble metal elements, which serve as surrogates for fission products, and actinides are made to that baseline composition. The partitioning of noble metal and actinide elements into alloy phases and the role of zirconium for incorporating these elements is discussed in this paper

  1. Adsorption of heavy metals by agroforestry waste derived activated ...

    African Journals Online (AJOL)

    SAM

    2014-04-02

    Apr 2, 2014 ... harmful effect on human physiology causing various diseases and disorders among which are nervous and renal breakdown, brain damage and convulsions (Kula et al., 2008; Kazemipour et al., 2008; Farooq et al., 2010). Conventional techniques used for the removal of metals from wastewater include ...

  2. Heavy metals pollution at municipal solid waste dumpsites in Kano ...

    African Journals Online (AJOL)

    Soil samples collected from two major dumpsites each in Kano and Kaduna states were investigated for heavy metals pollution. Each of the dumpsite was divided into north, south, east and west. Four soil samples were collected at a depth of 0-15 cm from each part and pooled to form a composite sample. Soil samples from ...

  3. Speciation and leaching of trace metal contaminants from e-waste contaminated soils.

    Science.gov (United States)

    Cui, Jin-Li; Luo, Chun-Ling; Tang, Chloe Wing-Yee; Chan, Ting-Shan; Li, Xiang-Dong

    2017-05-05

    Primitive electrical and electronic waste (e-waste) recycling activities have caused serious environmental problems. However, little is known about the speciation and leaching behaviors of metal contaminants at e-waste contaminated sites. This study investigated trace metal speciation/mobilization from e-waste polluted soil through column leaching experiments involving irrigation with rainwater for almost 2.5 years. Over the experimental period, Cu and Zn levels in the porewater were 0.14±0.08mg/L, and 0.16±0.08mg/L, respectively, increasing to 0.33±0.16mg/L, and 0.69±0.28mg/L with plant growth. The amounts of Cu, Zn, and Pb released in surface soil (0-2cm) contributed 43.8%, 22.5%, and 13.8%, respectively, to the original levels. The released Cu and Zn were primarily caused by the mobilization of the carbonate species of metals, including Cu(OH) 2 , CuCO 3 , and Zn 5 (CO 3 ) 2 (OH) 6 , and amorphous Fe/Mn oxides associated fractions characterized by sequential extraction coupling with X-ray absorption spectroscopy. During the experiments, trace metals were not detected in the effluent, and the re-sequestration of trace metals was mainly attributed to the adsorption on the abundant Fe/Mn oxides in the sub-layer soil. This study quantitatively elucidated the molecular speciation of Cu and Zn in e-waste contaminated soil during the column leaching process. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Heavy Metal Leaching as Affected by Long-Time Organic Waste Fertilizer Application.

    Science.gov (United States)

    Lekfeldt, Jonas Duus Stevens; Holm, Peter E; Kjærgaard, Charlotte; Magid, Jakob

    2017-07-01

    The recycling of urban waste products as fertilizers in agriculture may introduce contaminants such as heavy metals into soil that may leach and contaminate groundwater. In the present study, we investigated the leaching of heavy metals from intact soil cores collected in the long-term agricultural field trial CRUCIAL. At the time of sampling, the equivalent of >100 yr of urban waste fertilizers following Danish legislation had been applied. The leaching of Cu was significantly increased in the treatments receiving organic waste products compared with the unfertilized control but remained below the permissible level following Danish drinking water guidelines. The leaching of Cu was controlled primarily by the topsoil Cu content and by the leaching of dissolved organic carbon (DOC) but at the same time significantly correlated with leaching of colloids in soils that had not received fertilizer or had received an organic fertilizer with a low concentration of Cu. The leaching of Zn, Cd, and Co was not significantly increased in urban waste-fertilized treatments. The leaching of Mo was elevated in accelerated waste treatments (both agricultural and urban), and the leaching of Mo was linked to the leaching of DOC. Since leaching of Cr and Pb was strongly linked to the level of colloid leaching, leaching of these metals was reduced in the urban waste treatments. Overall, the results presented should not raise concern regarding the agricultural use of urban waste products in agriculture as long as the relevant guidelines are followed. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  5. Exposure assessment of heavy metals in an e-waste processing area in northern Vietnam.

    Science.gov (United States)

    Oguri, Tomoko; Suzuki, Go; Matsukami, Hidenori; Uchida, Natsuyo; Tue, Nguyen Minh; Tuyen, Le Huu; Viet, Pham Hung; Takahashi, Shin; Tanabe, Shinsuke; Takigami, Hidetaka

    2018-04-15

    In developing countries, inappropriate recycling of e-waste has resulted in the environmental release of toxicants, including heavy metals, that may have deleterious health effects. In this study, we estimated daily metal intakes in five households in a Vietnamese village located in an e-waste processing area and assessed the health risk posed by exposure to the metals. Garden soil, floor dust, 24-h duplicate diet, and ambient air samples were collected from five households in northern Vietnam in January 2014. All samples were acid-digested, and contents of Cd, Cu, Mn, Pb, Sb, and Zn were measured by using ICP mass spectrometry and ICP atomic emission spectroscopy. In addition, the soil, dust, and diet samples were subjected to an bioaccessibility extraction test to determine bioaccessible metal concentrations. Hazard quotients were estimated from bioaccessible metal concentrations, provisional tolerable weekly intakes, and reference doses. Garden soil and floor dust were estimated to be mainly contributors to daily Pb intake, as indicated by calculations using bioaccessible metal concentrations and the U.S. Environmental Protection Agency soil plus dust ingestion rate. Diet was suggested to contribute significantly to daily Cd, Cu, Mn, Sb, and Zn intake. Estimated metal exposures via inhalation were negligible, as indicated by calculations using International Atomic Energy Agency reference inhalation rates. The maximum hazard quotients were calculated as 0.2 (Cd), 0.09 (Cu), 0.3 (Mn), 0.6 (Pb), 0.2 (Sb), and 0.5 (Zn), on the basis of bioaccessible metal concentrations. The contributions of Cd, Cu, Mn, Sb, and Zn except Pb to potential noncancer risk for adult residents of the five households in the e-waste processing area may be low. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Studies of corrosion in metallic container for storage of high level radioactive wastes

    International Nuclear Information System (INIS)

    Azkarate, I.; Madina, V.; Insausti, M.

    1999-01-01

    The metallic container is one of the most important barriers that, along with engineered and natural barriers, will isolate high level nuclear waste in saline and granite geological formations from the geosphere. However, general and localized corrosion modes such as stress corrosion cracking (SCC), pitting, crevice corrosion and hydrogen damage can be active under disposal conditions, so the corrosion behaviour of the metal container material must be carefully studied. Several metals and their alloys have been proposed for the fabrication of nuclear waste containers including carbon steels, stainless steels, titanium and titanium alloys and copper and copper-base alloys. Carbon steels and copper alloys are considered for the two rock formations, titanium is considered for salt environments and the stainless steel only in the case of a granite formation. (Author)

  7. Implication of heavy metals distribution for a municipal solid waste management system - a case study in Shanghai

    International Nuclear Information System (INIS)

    Zhang Hua; He Pinjing; Shao Liming

    2008-01-01

    Heavy metal contamination in municipal solid waste (MSW) is of increasing concern. The occurrence and distribution of heavy metals in MSW and their implications for the integrated MSW management system in mega-cities have been investigated by means of material flow analysis based on a case study of Shanghai in China. A good statistical basis was provided through a one-year monitoring program on the mass and metals composition of the waste from three MSW treatment facilities. The results showed that the main heavy metals in the MSW were Zn, Cr, Cu, and Pb (on average > 100 mg kg -1 ), followed by Ni, Cd, and Hg. The MSW contained higher levels of Cu and Ni in metals, Cr and Pb in plastics, and Pb and Zn in the inorganic fractions. Regardless of the sources, the statistically similar heavy metal contents in the organic fractions indicated that effective blending and diffusion of heavy metals had taken place throughout the MSW collection, transfer, transportation, and storage, leading to cross-contamination of the waste fractions. PU (composed of putrescible waste and miscellaneous indistinguishable particles) contributed the majority of the heavy metals to the MSW, followed by plastics, as a result of the predominance in the overall composition of PU and plastics rather than from differences in their heavy metal contents. Therefore, manual or mechanical separation of some significantly heavy metal-rich fractions alone is not sufficient to reduce the heavy metal contents in the MSW. Source separation of organic waste and the diversion of tailored inorganic waste such as hazardous components, construction and demolition waste, etc., are proposed to control the heavy metal contamination in MSW. For the mixed MSW management system, physicochemical fractionation to exclude particles containing high levels of heavy metals can be conducted

  8. Monitoring Metal Pollution Levels in Mine Wastes around a Coal Mine Site Using GIS

    Science.gov (United States)

    Sanliyuksel Yucel, D.; Yucel, M. A.; Ileri, B.

    2017-11-01

    In this case study, metal pollution levels in mine wastes at a coal mine site in Etili coal mine (Can coal basin, NW Turkey) are evaluated using geographical information system (GIS) tools. Etili coal mine was operated since the 1980s as an open pit. Acid mine drainage is the main environmental problem around the coal mine. The main environmental contamination source is mine wastes stored around the mine site. Mine wastes were dumped over an extensive area along the riverbeds, and are now abandoned. Mine waste samples were homogenously taken at 10 locations within the sampling area of 102.33 ha. The paste pH and electrical conductivity values of mine wastes ranged from 2.87 to 4.17 and 432 to 2430 μS/cm, respectively. Maximum Al, Fe, Mn, Pb, Zn and Ni concentrations of wastes were measured as 109300, 70600, 309.86, 115.2, 38 and 5.3 mg/kg, respectively. The Al, Fe and Pb concentrations of mine wastes are higher than world surface rock average values. The geochemical analysis results from the study area were presented in the form of maps. The GIS based environmental database will serve as a reference study for our future work.

  9. Disintegration and size reduction of slags and metals after melt refining of contaminated metallic wastes

    International Nuclear Information System (INIS)

    Heshmatpour, B.; Copeland, G.L.; Heestand, R.L.

    1981-04-01

    Melting under an oxidizing slag is an attractive method of decontaminating and reducing the volume of radioactively contaminated metal scrap. The contaminants are concentrated in a relatively small volume of slag, which leaves the metal essentially clean. A potential method of permanently disposing of the resulting slags (and metals if necessary) is emplacing them into deep shale by grout hydrofracture. Suspension in grout mixtures requires that the slag and metal be granular. The feasibility of size-reducing slags and disintegrating metals and subsequently incorporating both into grout mixtures was demonstrated. Various types of slags were crushed with a small jaw crusher into particles smaller than 3 mm. Several metals were also melted and water-blasted into coarse metal powder or shot ranging in size from 0.05 to 3 mm. A simple low-pressure water atomizer having a multiple nozzle with a converging-line jet stream was developed and used for this purpose. No significant slag dust and steam were generated during slag crushing and liquid-metal water-blasting tests, indicating that contamination can be well contained within the system. The crushed slags and the coarse metal powders were suspendable in group fluids, which indicates probable disposability by shale hydrofracture. The granulation of slags and metals facilitates their containment, transport, and storage

  10. Rare and Rare-Earth Metals in Coal Processing Waste

    Science.gov (United States)

    Cherkasova, Tatiana; Cherkasova, Elizaveta; Tikhomirova, Anastasia; Bobrovni-kova, Alyona; Goryunova, Irina

    2017-11-01

    An urgent issue for power plants operating on solid fuels (coal) is the issue of utilization or use of accumulated production waste - ash and slag materials - in the related production. Ash-slag materials are classified as "waste", usually grade 5; tens of millions of tons of them being pro-duced annually in the Kemerovo region, which threatens the ecology of the region. At the same time, ash and slag is a very promising raw material. The use of this material as a base for the final product allows us to signifi-cantly expand the possibilities of using coal. The most widespread is the system of ash and slag involving in construction or as a replacement for sand in road construction, or as an additive to building mixtures. However, there are both industrially valuable and environmentally dangerous ele-ments in ash-slag materials. Ash-slag materials can be considered as inde-pendent ore deposits located on the surface and requiring the costs of their extraction.

  11. Metal accumulation in wild plants surrounding mining wastes

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, R. Carrillo [Soil Chemistry, IRENAT, Colegio de Postgraduados, Carr, Mexico-Texcoco km 36.5, Montecillo, Mexico 56230 (Mexico)]. E-mail: crogelio@colpos.mx; Gonzalez-Chavez, M.C.A. [Soil Microbiology, IRENAT, Colegio de Postgraduados, Carr, Mexico-Texcoco km 36.5, Montecillo, Mexico 56230 (Mexico)]. E-mail: carmeng@colpos.mx

    2006-11-15

    Four sites were selected for collection of plants growing on polluted soil developed on tailings from Ag, Au, and Zn mines at the Zacatecas state in Mexico. Trace element concentrations varied between sites, the most polluted area was at El Bote mine near to Zacatecas city. The ranges of total concentration in soil were as follows: Cd 11-47, Ni 19-26, Pb 232-695, Mn 1132-2400, Cu 134-186 and Zn 116-827 mg kg{sup -1} air-dried soil weight. All soil samples had concentrations above typical values for non-polluted soils from the same soil types (Cd 0.6 {+-} 0.3, Ni 52 {+-} 4, Pb 41 {+-} 3 mg kg{sup -1}). However, for the majority of samples the DTPA-extractable element concentrations were less than 10% of the total. Some of the wild plants are potentially metal tolerant, because they were able to grow in highly polluted substrates. Plant metal analysis revealed that most species did not translocate metals to their aerial parts, therefore they behave as excluder plants. Polygonum aviculare accumulated Zn (9236 mg kg{sup -1}) at concentrations near to the criteria for hyperaccumulator plants. Jatropha dioica also accumulated high Zn (6249 mg kg{sup -1}) concentrations. - Polygonum aviculare and Jatropha dioica accumulated Zn at concentrations near to the criteria for hyperaccumulator plants.

  12. Metal accumulation in wild plants surrounding mining wastes.

    Science.gov (United States)

    González, R Carrillo; González-Chávez, M C A

    2006-11-01

    Four sites were selected for collection of plants growing on polluted soil developed on tailings from Ag, Au, and Zn mines at the Zacatecas state in Mexico. Trace element concentrations varied between sites, the most polluted area was at El Bote mine near to Zacatecas city. The ranges of total concentration in soil were as follows: Cd 11-47, Ni 19-26, Pb 232-695, Mn 1132-2400, Cu 134-186 and Zn 116-827 mg kg(-1) air-dried soil weight. All soil samples had concentrations above typical values for non-polluted soils from the same soil types (Cd 0.6+/-0.3, Ni 52+/-4, Pb 41+/-3mg kg(-1)). However, for the majority of samples the DTPA-extractable element concentrations were less than 10% of the total. Some of the wild plants are potentially metal tolerant, because they were able to grow in highly polluted substrates. Plant metal analysis revealed that most species did not translocate metals to their aerial parts, therefore they behave as excluder plants. Polygonum aviculare accumulated Zn (9236 mg kg(-1)) at concentrations near to the criteria for hyperaccumulator plants. Jatropha dioica also accumulated high Zn (6249 mg kg(-1)) concentrations.

  13. Evaluation of extractant-coated magnetic microparticles for the recovery of hazardous metals from waste solution

    International Nuclear Information System (INIS)

    Kaminski, M. D.

    1998-01-01

    A magnetically assisted chemical separation (MACS) process was developed earlier at Argonne National Laboratory (ANL). This compact process was designed for the separation of transuranics (TRU) and radionuclides from the liquid waste streams that exist at many DOE sites, with an overall reduction in waste volume requiring disposal. The MACS process combines the selectivity afforded by solvent extractant/ion exchange materials with magnetic separation to provide an efficient chemical separation. Recently, the MACS process has been evaluated with acidic organophosphorus extractants for hazardous metal recovery from waste solutions. Moreover, process scale-up design issues have been addressed with respect to particle filtration and recovery. Two acidic organophosphorus compounds have been investigated for hazardous metal recovery, bis(2,4,4-trimethylpentyl) phosphinic acid (Cyanexreg-sign 272) and bis(2,4,4-trimethylpentyl) dithiophosphinic acid (Cyanexreg-sign 301). Coated onto magnetic microparticles, these extractants demonstrated superior recovery of hazardous metals from solution, relative to what was expected on the basis of results from solvent extraction experiments. The results illustrate the diverse applications of MACS technology for dilute waste streams. Preliminary process scale-up experiments with a high-gradient magnetic separator at Oak Ridge National Laboratory have revealed that very low microparticle loss rates are possible

  14. Removal of heavy metals from aqueous phases using chemically modified waste Lyocell fiber

    Energy Technology Data Exchange (ETDEWEB)

    Bediako, John Kwame; Wei, Wei; Kim, Sok; Yun, Yeoung-Sang, E-mail: ysyun@jbnu.ac.kr

    2015-12-15

    Highlights: • Waste Lyocell fiber was chemically modified into cellulose xanthate. • The sorbent showed high affinity for Pb(II), Cd(II) and Cu(II) ions. • The sorbent also showed strong Cu(II) selectivity in Pb(II)–Cd(II)–Cu(II) ternary metal solutions. - Abstract: In this study, an outstanding performance of chemically modified waste Lyocell for heavy metals treatment is reported. The sorbent, which was prepared by a simple and concise method, was able to bind heavy metals such as Pb(II), Cu(II) and Cd(II), with very high efficiencies. The binding mechanisms were studied through adsorption and standard characterization tests such as scanning electron microscopy, energy-dispersive spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction analyses. Adsorption kinetics was very fast and attained equilibrium within 5 min in all metals studied. The maximum single metal uptakes were 531.29 ± 0.28 mg/g, 505.64 ± 0.21 mg/g, and 123.08 ± 0.26 mg/g for Pb(II), Cd(II) and Cu(II), respectively. In ternary metal systems, Cu(II) selectivity was observed and the underlying factors were discussed. The sorbent by its nature, could be very effective in treating large volumes of wastewater with the contact of very little amount.

  15. Study of the leaching of heavy metals from waste water sludge and incinerator's ash, using coupled thermostated columns and DTPA as complex agent; Estudio de la extraccion de metales pesados de lodos y cenizas de aguas residuales usando columnas termostatizadas acopladas y DTPA como agente complejante

    Energy Technology Data Exchange (ETDEWEB)

    Vite T, J.; Vite T, M.; Guerrero D, J.; Carreno de Leon, M.C. [Departamento de Estudios del Ambiente, Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    We studied the metallic composition from waste water sludge and incinerators ashes of an incinerator located in Toluca, Mexico, the qualitative studies were made using the Activation Analysis technique, and fluorescence X-ray techniques. The quantitative analysis of heavy metals in the wastes were made using Inductively coupled plasma atomic emission spectrometry (Icp-Aes). For leaching the samples, we used four coupled thermostated columns, each one had a p H of 2,5, 7 and 10. The flux of the air was of 1600 cc/min. The temperature was maintain constant in 60 Centigrade using a thermostated system. For this study we used 100 g of wastes mixed with mineral acid or sodium hydroxide to reach p H 2,5,7 and 10. We added a reducing and tensoactive agents and finally DTPA as complex agent. With this method, we obtain a better leaching efficiency using a complex agent. However the high DTPA cost, make this process expansive that is why we recommend to work with another classes of complex agents, that be cheaper to leach metals of different chemistry matrix. (Author)

  16. Waste Derived Sorbents and Their Potential Roles in Heavy Metal Remediation Applications

    Directory of Open Access Journals (Sweden)

    Chiang Y. W.

    2013-04-01

    Full Text Available Inorganic waste materials that have the suitable inherent characteristics could be used as precursors for the synthesis of micro- and mesoporous materials, which present great potential to be re-utilized as sorbent materials for heavy metal remediation. Three inorganic waste materials were studied in the present work: water treatment residuals (WTRs from an integrated drinking water/wastewater treatment plant, and fly ash and bottom ash samples from a municipal solid waste incinerator (MSWI. These wastes were converted into three sorbent materials: ferrihydrite-like materials derived from drying of WTRs, hydroxyapatite-like material derived from ultrasound assisted synthesis of MSWI fly ash with phosphoric acid solution, and a zeolitic material derived from alkaline hydrothermal conversion of MSWI bottom ash. The performance of these materials, as well as their equivalent commercially available counterparts, was assessed for the adsorption of multiple heavy metals (As, Cd, Co, Ni, Pb, Zn from synthetic solutions, contaminated sediments and surface waters; and satisfactory results were obtained. In addition, it was observed that the combination of sorbents into sorbent mixtures enhanced the performance levels and, where applicable, stabilized inherently mobile contaminants from the waste derived sorbents.

  17. Application of vacuum metallurgy to separate pure metal from mixed metallic particles of crushed waste printed circuit board scraps.

    Science.gov (United States)

    Zhan, Lu; Xu, Zhenming

    2008-10-15

    The principle of separating pure metal from mixed metallic particles (MMPs) byvacuum metallurgy is that the vapor pressures of various metals at the same temperature are different As a result, the metal with high vapor pressure and low boiling point can be separated from the mixed metals through distillation or sublimation, and then it can be recycled through condensation under a certain condition. The vacuum metallurgy separation (VMS) of MMPs of crushed waste printed circuit boards (WPCBs) has been studied in this paper. Theoretical analyses show that the MMPs (copper, zinc, bismuth, lead, and indium, for example) can be separated by vacuum metallurgy. The copper particles (0.15-0.20 mm) and zinc particles (<0.30 mm) were chosen to simulate the MMPs of crushed WPCBs. Experimental results show that the separated efficiency of zinc in the copper-rich particles achieves 96.19 wt % when the vacuum pressure is 0.01-0.10 Pa, the heating temperature is 1123 K, and the heating time is 105 min. Under this operation condition, the separated efficiency of zinc in the copper-rich particles from crushed WPCBs achieves 97.00 wt % and the copper purity increases from 90.68 to 99.84 wt %.

  18. Heavy Metals Removal from Sewage Sludge and Municipal Solid Waste (MSW by Co-Composting Process

    Directory of Open Access Journals (Sweden)

    Vahid Babaee Darzi

    2017-07-01

    Full Text Available Background & Aims of the Study: One of the most important pollutants in drinking water, air and soils is heavy metals. It is very harmful for humans and other live organisms. The purpose of this study was the usage of a co-composting process for removal of heavy metals from municipal solid waste and sewage sludge. Materials and Methods: This experimental study was a conducted sewage sludge and municipal solid waste. For collection of samples from urban solid waste composting and wastewater treatment plant, a 200 mL polyethylene bottles was used, samples after acidification were stored in a dark place at 4°C temperature until the metals analysis the heavy metals values remaining in the samples was measured by graphite furnace absorption spectrometer method (Varian, SpectrAA 240, Australia. In this study, we used SPSS version 16 for data processing; and they were also analyzed by descriptive statistics. Results: Result of this study showed that values of C/N in the first, second and third stage compost were 31.7, 27.3 and 41.8, respectively. Based on the result of this study the value of removal of Cd with 9.8 mg kg-1 in first stage and Cr, Cu and Zn with 89, 21 and 87.6 mg kg-1 in third stage were highest treatment. Conclusion: Our results show that co-composting process between many treatment processes having to be cost effective for heavy metal removal from solid waste and wastewater treatment.

  19. An environmentally friendly ball milling process for recovery of valuable metals from e-waste scraps.

    Science.gov (United States)

    Zhang, Zhi-Yuan; Zhang, Fu-Shen; Yao, TianQi

    2017-10-01

    The present study reports a mechanochemical (MC) process for effective recovery of copper (Cu) and precious metals (i.e. Pd and Ag) from e-waste scraps. Results indicated that the mixture of K 2 S 2 O 8 and NaCl (abbreviated as K 2 S 2 O 8 /NaCl hereafter) was the most effective co-milling reagents in terms of high recovery rate. After co-milling with K 2 S 2 O 8 /NaCl, soluble metallic compounds were produced and consequently benefit the subsequent leaching process. 99.9% of Cu and 95.5% of Pd in the e-waste particles could be recovered in 0.5mol/L diluted HCl in 15min. Ag was concentrated in the leaching residue as AgCl and then recovered in 1mol/L NH 3 solution. XRD and XPS analysis indicated that elemental metals in the raw materials were transformed into their corresponding oxidation state during ball milling process at low temperature, implying that solid-solid phase reactions is the reaction mechanism. Based on the results and thermodynamic parameters of the probable reactions, possible reaction pathways during ball milling were proposed. Suggestion on category of e-waste for ball milling process was put forward according to the experiment results. The designed metal recovery process of this study has the advantages of highly recovery rate and quick leaching speed. Thus, this study offers a promising and environmentally friendly method for recovering valuable metals from e-waste. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Spatial distribution of heavy metal contamination in soils near a primitive e-waste recycling site.

    Science.gov (United States)

    Quan, Sheng-Xiang; Yan, Bo; Yang, Fan; Li, Ning; Xiao, Xian-Ming; Fu, Jia-Mo

    2015-01-01

    The total concentrations of 12 heavy metals in surface soils (SS, 0-20 cm), middle soils (MS, 30-50 cm) and deep soils (DS, 60-80 cm) from an acid-leaching area, a deserted paddy field and a deserted area of Guiyu were measured. The results showed that the acid-leaching area was heavily contaminated with heavy metals, especially in SS. The mean concentrations of Ni, Cu, Zn, Cd, Sn, Sb and Pb in SS from the acid-leaching area were 278.4, 684.1, 572.8, 1.36, 3,472, 1,706 and 222.8 mg/kg, respectively. Heavy metal pollution in the deserted paddy field was mainly concentrated in SS and MS. The average values of Sb in SS and MS from the deserted paddy field were 16.3 and 20.2 mg/kg, respectively. However, heavy metal contamination of the deserted area was principally found in the DS. Extremely high concentrations of heavy metals were also observed at some special research sites, further confirming that the level of heavy metal pollution was very serious. The geoaccumulation index (Igeo) values revealed that the acid-leaching area was severely polluted with heavy metals in the order of Sb > Sn > Cu > Cd > Ni > Zn > Pb, while deserted paddy field was contaminated predominately by metals in the order of Sb > Sn > Cu. It was obvious that the concentrations of some uncommon contaminants, such as Sb and Sn, were higher than principal contaminants, such as Ni, Cu, Zn and Pb, suggesting that particular attention should be directed to Sn and Sb contamination in the future research of heavy metals in soils from e-waste-processing areas. Correlation analysis suggested that Li and Be in soils from the acid-leaching area and its surrounding environment might have originated from other industrial activities and from batteries, whereas Ni, Cu, Zn, Cd, Pb, Sn and Sb contamination was most likely caused by uncontrolled electronic waste (e-waste) processing. These results indicate the significant need for optimisation of e-waste-dismantling technologies and remediation of polluted soil

  1. Natural arsenic attenuation via metal arsenate precipitation in soils contaminated with metallurgical wastes: II. Cumulative evidence and identification of minor processes

    International Nuclear Information System (INIS)

    Gutiérrez-Ruiz, M.E.; Ceniceros-Gómez, A.E.; Villalobos, M.; Romero, F.; Santiago, P.

    2012-01-01

    Highlights: ► Aqueous As in soils surrounding a smelting plant decreased through a natural attenuation process. ► As in water extracts from soils matched thermodynamic equilibrium modeling results. ► Modeling indicates that lead arsenates of low-solubility control As mobility. ► Sequential chemical extractions are consistent with the solubility behavior of lead arsenates. ► Microscopic evidence of lead arsenates was obtained by HRTEM–EDS. - Abstract: Accurate identification of individual As species in contaminated environments is critical because the toxicology, mobility and adsorptive properties of this element may vary substantially with its chemical forms and oxidation states. The goal of this work was to relate the geochemical behavior of As in soils contaminated by a lead smelter in Mexico, with its chemical speciation, and to achieve direct identification of low-solubility poorly-crystalline metal arsenates. Arsenic was identified as the most mobile trace element in the wastes from the smelting plant. Arsenic solubility in soils was significantly lower than its solubility in wastes, showing natural attenuation of this element. Its solubility in soil was quantitatively described in selected samples through thermodynamic equilibrium modeling. The results indicated that As solubility is controlled by solid Pb and Cu arsenate formation. The behaviors of the sequential chemical extractions were consistent with the presence of the predicted arsenates. Microscopic evidence of the formation of solid metal arsenates were obtained in fine soil fractions of selected samples with high As contents, by using the following complementary techniques: X-ray diffraction, scanning electron microscopy and transmission electron microscopy, both coupled with energy dispersive X-ray spectroscopy, and the latter with a high angle annular dark field detector. All results supported the formation of low-solubility Pb arsenates as controlling As mobility in the samples

  2. The evaluation of solidifying performance of heavy metal waste using cementitious materials (2)

    International Nuclear Information System (INIS)

    Fujita, Hideki; Harasawa, Shuichi

    2005-02-01

    Some of radioactive waste generated from JNC's facilities contain the poisonous substances such as lead, cadmium and mercury. In order to establish an appropriate method of the treatment of these heavy metals, solidification performance was evaluated using cementitious materials. In this report, the solidification performance of lead and mercury, which accounts for relatively high ratio in total wastes, was evaluated. The results are summarized below: 1. The test of stabilization process of mercury. The conversion process from mercury to the powdery mercury sulfide (red) was examined on the beaker scale. As a result, it was confirmed that the conversion was possible using the liquid phase reaction at 80deg C by the addition of sulfur powder with the NaOH solution. After the process, the mercury concentration in the filtrate was relatively high (0.6 mass%), so it was judged that the reuse of the recovered mercury waste fluid was indispensable. 2. The fabrication and evaluation of solidified wastes. The solidified waste were fabricated with cementitious material, and were evaluated by the measurement of one-axis compressive strength, the elution ratio of lead, mercury and so on. Powdery lead sulfide and the mercury sulfide of reagent were used as model waste. (1) solidification test of the lead waste. It was confirmed one-axis compressive strength for all solidified waste to pass the technical standards 15 kg/cm 2 (1.5 Mpa) for homogeneously solidified waste as the Low-level Radioactive Waste Disposal Center in Aomori Prefecture, and as for the elution ratio of lead, it had obtained the better result (0.06 mg/L) at the case of solidification of sulfide lead 30 mass% packed in the total solidified waste by using Highly Fly-ash contained Silica fume Cement (HFSC) than standard value (0.3 mg/L) at Regulations of Waste Management and Public Cleansing Law. Additionally, it was confirmed the using admixture of the inorganic reducing agent such as the Iron (II) chloride

  3. Recovery of Precious and Base Metals from Waste Printed Circuit Boards Using a Sequential Leaching Procedure

    Science.gov (United States)

    Batnasan, Altansukh; Haga, Kazutoshi; Shibayama, Atsushi

    2018-02-01

    This paper considers the issue of recycling of waste printed circuit boards (WPCBs) containing precious and base metals in appreciable amounts. High-pressure oxidative leaching (HPOL) with dilute sulfuric acid resulted in removal of a significant amount of base metals from a WPCB ash sample obtained by incineration at 800°C. The parameters investigated in the precious metal leaching from WPCB residue after HPOL included the sulfuric acid concentration, thiourea concentration, oxidant concentration, leaching temperature, and leaching time. Recovery of gold, silver, and palladium of 100%, 81%, and 13% from the WPCB residue sample was achieved by thiourea leaching under optimized conditions. The results show that the efficiency of precious metal dissolution from the WPCB sample using thiourea solution depended strongly on the concentration of both thiourea and oxidant.

  4. Further studies on melting of radioactive metallic wastes from the dismantling of nuclear installations

    International Nuclear Information System (INIS)

    Diepenau, H.; Seidler, M.

    1991-01-01

    Melting of radioactive waste metal from the dismantling/refurbishing of nuclear installations is an acceptable way for nuclear waste recycling. This material can be used for the casting of qualified products such as type A- and type B-waste containers. The results of the melting facility -TAURUS- were used to build the industrial scale melting facility -CARLA- at Siempelkamp. The test results and the longterm-behaviour of the facility showed that the licensing conditions can be respected. The radiation exposure of workers was in the range of the admissible limit for non-exposed people. The radiation exposure of the environment is far below the value of the German Radiation Protection Law. The activity distribution within the product is homogeneous, so that its activity can be measured exactly before it is sent back in the nuclear area. By melting waste copper it is possible to respect the specific limits for unrestricted reuse, whereas for brass the limit for conditioned reuse in the industrial field was reached. Radioactive carbon can only be bound in form of small graphite lamellas or nodules in the cast iron; i.e. radioactive carbon can only be added to the melt as crushed material. During the research programme 2000 Mg of waste steel was melted at industrial scale and mainly products such as shielding blocks and waste containers were produced. 12 figs., 27 tabs., 6 refs

  5. Spatial assessment of soil contamination by heavy metals from informal electronic waste recycling in Agbogbloshie, Ghana.

    Science.gov (United States)

    Kyere, Vincent Nartey; Greve, Klaus; Atiemo, Sampson M

    2016-01-01

    This study examined the spatial distribution and the extent of soil contamination by heavy metals resulting from primitive, unconventional informal electronic waste recycling in the Agbogbloshie e-waste processing site (AEPS) in Ghana. A total of 132 samples were collected at 100 m intervals, with a handheld global position system used in taking the location data of the soil sample points. Observing all procedural and quality assurance measures, the samples were analyzed for barium (Ba), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn), using X-ray fluorescence. Using environmental risk indices of contamination factor and degree of contamination (C deg ), we analyzed the individual contribution of each heavy metal contamination and the overall C deg . We further used geostatistical techniques of spatial autocorrelation and variability to examine spatial distribution and extent of heavy metal contamination. Results from soil analysis showed that heavy metal concentrations were significantly higher than the Canadian Environmental Protection Agency and Dutch environmental standards. In an increasing order, Pb>Cd>Hg>Cu>Zn>Cr>Co>Ba>Ni contributed significantly to the overall C deg . Contamination was highest in the main working areas of burning and dismantling sites, indicating the influence of recycling activities. Geostatistical analysis also revealed that heavy metal contamination spreads beyond the main working areas to residential, recreational, farming, and commercial areas. Our results show that the studied heavy metals are ubiquitous within AEPS and the significantly high concentration of these metals reflect the contamination factor and C deg , indicating soil contamination in AEPS with the nine heavy metals studied.

  6. Spatial assessment of soil contamination by heavy metals from informal electronic waste recycling in Agbogbloshie, Ghana

    Science.gov (United States)

    Greve, Klaus; Atiemo, Sampson M.

    2016-01-01

    Objectives This study examined the spatial distribution and the extent of soil contamination by heavy metals resulting from primitive, unconventional informal electronic waste recycling in the Agbogbloshie e-waste processing site (AEPS) in Ghana. Methods A total of 132 samples were collected at 100 m intervals, with a handheld global position system used in taking the location data of the soil sample points. Observing all procedural and quality assurance measures, the samples were analyzed for barium (Ba), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn), using X-ray fluorescence. Using environmental risk indices of contamination factor and degree of contamination (Cdeg), we analyzed the individual contribution of each heavy metal contamination and the overall Cdeg. We further used geostatistical techniques of spatial autocorrelation and variability to examine spatial distribution and extent of heavy metal contamination. Results Results from soil analysis showed that heavy metal concentrations were significantly higher than the Canadian Environmental Protection Agency and Dutch environmental standards. In an increasing order, Pb>Cd>Hg>Cu>Zn>Cr>Co>Ba>Ni contributed significantly to the overall Cdeg. Contamination was highest in the main working areas of burning and dismantling sites, indicating the influence of recycling activities. Geostatistical analysis also revealed that heavy metal contamination spreads beyond the main working areas to residential, recreational, farming, and commercial areas. Conclusions Our results show that the studied heavy metals are ubiquitous within AEPS and the significantly high concentration of these metals reflect the contamination factor and Cdeg, indicating soil contamination in AEPS with the nine heavy metals studied. PMID:26987962

  7. Metal leachability, heavy metals, polycyclic aromatic hydrocarbons and polychlorinated biphenyls in fly and bottom ashes of a medical waste incineration facility.

    Science.gov (United States)

    Valavanidis, Athanasios; Iliopoulos, Nikiforos; Fiotakis, Konstantinos; Gotsis, George

    2008-06-01

    Medical waste from hospitals and other healthcare institutions has become an imperative environmental and public safety problem. Medical waste in Greece has become one of the most urgent environmental problems, because there are 14,000 tons produced annually, of which only a small proportion is incinerated. In the prefecture of Attica there is only one modern municipal medical waste incinerator (started 2004) burning selected infectious hospital waste (5-6 tons day(-1)). Fly and bottom residues (ashes) are collected and stored temporarily in barrels. High values of metal leachability prohibit the landfilling of these ashes, as imposed by EU directives. In the present study we determined quantitatively the heavy metals and other elements in the fly and bottom ashes of the medical waste incinerator, by inductively coupled plasma emission spectrometry (ICP) and by energy dispersive X-ray analysis (EDAX). Heavy metals, which are very toxic, such as Pb, Cd, Ni, Cr, Cu and Zn were found in high concentrations in both fly and bottom ashes. Metal leachability of fly and bottom ashes by water and kerosene was measured by ICP and the results showed that toxic metals in both ashes, such as Pb, Cr, Cd, Cu and Zn, have high leaching values. These values indicate that metals can become soluble and mobile if ash is deposited in landfills, thus restricting their burial according to EU regulations. Analysis of polychlorinated biphenyls and polycyclic aromatic hydrocarbons in fly and bottom ashes showed that their concentrations were very low. This is the first known study in Greece and the results showed that incineration of medical waste can be very effective in minimizing the most hazardous and infectious health-care waste. The presence of toxic metals with high leachability values remains an important draw back of incineration of medical waste and various methods of treating these residues to diminish leaching are been considered at present to overcome this serious technical

  8. Recovery of iron metal from waste water by aluminosilicates

    International Nuclear Information System (INIS)

    Nibou, D.; Amedjkouh, A.; Lebaili, S.

    1997-04-01

    The present work deals with the recovery of iron metal by ion exchange in using some aluminosilicates as NaY and NaX of different Si/AL rations, NaZSM-5 zeolites. These materials were synthetized by hydrothermaly processes using amorphous gels of silicium, alumina and alkali solution in water presence. The product samples were characterized by X ray diffraction and observed and analysed by scanning electronic microscopy method. The obtained results show that aluminosilicates seen to be very effective in iron recovery. The fixation rate was varied from 1 to 55% and the texture of these materials was also studies by X ray diffraction. It seems that the aluminosilicates structures still intact after ion exchange processes

  9. The effect of treatment with activated carbon on the metal content in reuse of lubricating oil waste

    Directory of Open Access Journals (Sweden)

    Riyanto

    2018-01-01

    Full Text Available The effect of treatment with activated carbon to the metal content in the reuse of lubricating oil waste has been done. Waste lubricating oil has treatment using 1-butanol and KOH as a solvent and coagulant. The research studies of the effect of activated carbon to the metals are Pb, Cr, Ca, Mg and Fe in lubrication oil waste after treatment. Waste lubricating oil treatment by the adsorption method using activated carbon with various weight are 0,5; 1,0; and 1,5 g. The metal concentrate was analysis after and before treatment using Atomic Adsorption Spectrophotometer (AAS. The analysis result shown the best weight of activated carbon for decreased of metals contains in lubricating oil waste is 1.5 g. Metal concentration of Pb, Cr, Ca, Mg and Fe in lubricating oil waste before treatment are 181.0002, 10.7198, 1019.0220, 325.8788 and 365.1329 mg/L (ppm, respectively. Metal concentration of Pb, Cr, Ca, Mg and Fe in lubricating oil waste after treatment are 47.5670, not detection, 2.6871, 44.3251 and 222.043 mg/L (ppm, respectively. Base on ASTM D5185 standard shown the Ca, Mg and Cr metals concentration according to the new lubricating oil quality standard. Pb and Fe metals concentration after process are still above the new lubricating oil quality standard. As a conclusion is activated carbon is a good material for treatment of waste lubricating oil, especially to reduce metal concentrations.

  10. Rare and Rare-Earth Metals in Coal Processing Waste

    Directory of Open Access Journals (Sweden)

    Cherkasova Tatiana

    2017-01-01

    Full Text Available An urgent issue for power plants operating on solid fuels (coal is the issue of utilization or use of accumulated production waste - ash and slag materials - in the related production. Ash-slag materials are classified as “waste”, usually grade 5; tens of millions of tons of them being pro-duced annually in the Kemerovo region, which threatens the ecology of the region. At the same time, ash and slag is a very promising raw material. The use of this material as a base for the final product allows us to signifi-cantly expand the possibilities of using coal. The most widespread is the system of ash and slag involving in construction or as a replacement for sand in road construction, or as an additive to building mixtures. However, there are both industrially valuable and environmentally dangerous ele-ments in ash-slag materials. Ash-slag materials can be considered as inde-pendent ore deposits located on the surface and requiring the costs of their extraction.

  11. Heavy metals in soil at a waste electrical and electronic equipment processing area in China.

    Science.gov (United States)

    Gu, Weihua; Bai, Jianfeng; Yao, Haiyan; Zhao, Jing; Zhuang, Xuning; Huang, Qing; Zhang, Chenglong; Wang, JingWei

    2017-11-01

    For the objective of evaluating the contamination degree of heavy metals and analysing its variation trend in soil at a waste electrical and electronic equipment processing area in Shanghai, China, evaluation methods, which include single factor index method, geo-accumulation index method, comprehensive pollution index method, and potential ecological risk index method, were adopted in this study. The results revealed that the soil at a waste electrical and electronic equipment processing area was polluted by arsenic, cadmium, copper, lead, zinc, and chromium. It also demonstrated that the concentrations of heavy metals were increased over time. Exceptionally, the average value of the metalloid (arsenic) was 73.31 mg kg -1 in 2014, while it was 58.31 mg kg -1 in the first half of 2015, and it was 2.93 times and 2.33 times higher than that of the Chinese Environmental Quality Standard for Soil in 2014 and the first half of 2015, respectively. The sequences of the contamination degree of heavy metals in 2014 and the first half of 2015 were cadmium > lead > copper > chromium > zinc and cadmium > lead > chromium > zinc > copper. From the analysis of the potential ecological risk index method, arsenic and cadmium had higher ecological risk than other heavy metals. The integrated ecological risk index of heavy metals (cadmium, copper, lead, zinc, and chromium) and metalloid (arsenic) was 394.10 in 2014, while it was 656.16 in the first half of 2015, thus documenting a strong ecological risk.

  12. Initial Evaluation of Processing Methods for an Epsilon Metal Waste Form

    Energy Technology Data Exchange (ETDEWEB)

    Crum, Jarrod V.; Strachan, Denis M.; Zumhoff, Mac R.

    2012-06-11

    During irradiation of nuclear fuel in a reactor, the five metals, Mo, Pd, Rh, Ru, and Tc, migrate to the fuel grain boundaries and form small metal particles of an alloy known as epsilon metal ({var_epsilon}-metal). When the fuel is dissolved in a reprocessing plant, these metal particles remain behind with a residue - the undissolved solids (UDS). Some of these same metals that comprise this alloy that have not formed the alloy are dissolved into the aqueous stream. These metals limit the waste loading for a borosilicate glass that is being developed for the reprocessing wastes. Epsilon metal is being developed as a waste form for the noble metals from a number of waste streams in the aqueous reprocessing of used nuclear fuel (UNF) - (1) the {var_epsilon}-metal from the UDS, (2) soluble Tc (ion-exchanged), and (3) soluble noble metals (TRUEX raffinate). Separate immobilization of these metals has benefits other than allowing an increase in the glass waste loading. These materials are quite resistant to dissolution (corrosion) as evidenced by the fact that they survive the chemically aggressive conditions in the fuel dissolver. Remnants of {var_epsilon}-metal particles have survived in the geologically natural reactors found in Gabon, Africa, indicating that they have sufficient durability to survive for {approx} 2.5 billion years in a reducing geologic environment. Additionally, the {var_epsilon}-metal can be made without additives and incorporate sufficient foreign material (oxides) that are also present in the UDS. Although {var_epsilon}-metal is found in fuel and Gabon as small particles ({approx}10 {micro}m in diameter) and has survived intact, an ideal waste form is one in which the surface area is minimized. Therefore, the main effort in developing {var_epsilon}-metal as a waste form is to develop a process to consolidate the particles into a monolith. Individually, these metals have high melting points (2617 C for Mo to 1552 C for Pd) and the alloy is

  13. Initial Evaluation of Processing Methods for an Epsilon Metal Waste Form

    International Nuclear Information System (INIS)

    Crum, Jarrod V.; Strachan, Denis M.; Zumhoff, Mac R.

    2012-01-01

    During irradiation of nuclear fuel in a reactor, the five metals, Mo, Pd, Rh, Ru, and Tc, migrate to the fuel grain boundaries and form small metal particles of an alloy known as epsilon metal ((var e psilon)-metal). When the fuel is dissolved in a reprocessing plant, these metal particles remain behind with a residue - the undissolved solids (UDS). Some of these same metals that comprise this alloy that have not formed the alloy are dissolved into the aqueous stream. These metals limit the waste loading for a borosilicate glass that is being developed for the reprocessing wastes. Epsilon metal is being developed as a waste form for the noble metals from a number of waste streams in the aqueous reprocessing of used nuclear fuel (UNF) - (1) the (var e psilon)-metal from the UDS, (2) soluble Tc (ion-exchanged), and (3) soluble noble metals (TRUEX raffinate). Separate immobilization of these metals has benefits other than allowing an increase in the glass waste loading. These materials are quite resistant to dissolution (corrosion) as evidenced by the fact that they survive the chemically aggressive conditions in the fuel dissolver. Remnants of (var e psilon)-metal particles have survived in the geologically natural reactors found in Gabon, Africa, indicating that they have sufficient durability to survive for ∼ 2.5 billion years in a reducing geologic environment. Additionally, the (var e psilon)-metal can be made without additives and incorporate sufficient foreign material (oxides) that are also present in the UDS. Although (var e psilon)-metal is found in fuel and Gabon as small particles (∼10 (micro)m in diameter) and has survived intact, an ideal waste form is one in which the surface area is minimized. Therefore, the main effort in developing (var e psilon)-metal as a waste form is to develop a process to consolidate the particles into a monolith. Individually, these metals have high melting points (2617 C for Mo to 1552 C for Pd) and the alloy is expected

  14. Native fungi as metal remediators: Silver myco-accumulation from metal contaminated waste-rock dumps (Libiola Mine, Italy).

    Science.gov (United States)

    Cecchi, Grazia; Marescotti, Pietro; Di Piazza, Simone; Zotti, Mirca

    2017-03-04

    Metal contamination constitutes a major source of pollution globally. Many recent studies emphasized the need to develop cheap and green technologies for the remediation or reclamation of environmental matrices contaminated by heavy metals. In this context, fungi are versatile organisms that can be exploited for bioremediation activities. In our work, we tested silver (Ag) bioaccumulation capabilities of three microfungal strains (Aspergillus alliaceus Thom & Church, Trichoderma harzianum Rifai, Clonostachys rosea (Link) Schroers, Samuels, Seifert & W. Gams) isolated from a silver polluted site. The aim was to select silver tolerant native strains and test their potential silver uptake. Among the three species tested, T. harzianum was the most efficient strain to tolerate and accumulate silver, showing an uptake capability of 153 mg L -1 taken at the Ag concentration of 330 mg L -1 . Our study highlights the potential use of native microfungi spontaneously growing in sulphide-rich waste rock dumps, for silver bioaccumulation and bioremediation.

  15. Biorecovered precious metals from industrial wastes: single-step conversion of a mixed metal liquid waste to a bioinorganic catalyst with environmental application.

    Science.gov (United States)

    Mabbett, Amanda N; Sanyahumbi, Douglas; Yong, Ping; Macaskie, Lynne E

    2006-02-01

    The complete and continuous reduction of 1 mM Cr(VI) to Cr(III) was achieved in a flow-through reactor using a novel bioinorganic catalyst ("MM-bio-Pd(0)"), which was produced by single-step reduction of platinum group metals (PGM) from industrial waste solution onto biomass of Desulfovibrio desulfuricans ATCC 29577. Two flow-through reactor systems were compared using both "MM-bioPd(0)" and chemically reduced Pd(0). Reactors containing the latter removed Cr(VI) for 1 week only at the expense of formate as the electron donor, whereas the former gave complete Cr(VI) removal for 3 months of continuous operation. Mass balance analysis showed 100% reduction of Cr(VI) to soluble Cr(III) in the bioreactor exit solution. With the use of electron paramagnetic resonance (EPR) no intermediate Cr(V) species could be detected. Pd(0) was biodeposited similarly using Escherichia coliMC4100 and "bio-Pd(0)". The latter was used to recover Pd(II) from two acidic industrial waste leachates to generate two types of "MM-bio-Pd(0)": "SI-bio-Pd(0)" and "SII-bio-Pd(0)", respectively. The biomaterial composition was comparable in both cases, and the catalytic activity was related inversely to the amount of chloride in the waste leachate from which it was derived.

  16. A Potential Bio-Sorbent for Heavy Metals in the Remediation of Waste Water

    Directory of Open Access Journals (Sweden)

    Mohammad Laskar

    2016-12-01

    Full Text Available Bay leaves are used for flavoring in cold drinks production, in bakery goods, sauces, confectionary products and liquors. The waste generated from these sources has been valorized by attempting the remediation of waste water. Hence, adsorption of toxic metals onto Bay leaves has been investigated after optimizing the experimental parameters, namely the pH, contact time, adsorbent and Zn (II concentrations as well as the temperature of the equilibrium mixture (consisting of the metal solution in contact with the adsorbent. The participation of the constituent functional groups, of the adsorbent, was ascertained with Fourier Transform spectroscopic studies. The mode of adsorption was examined by employing important isotherm models, namely Langmuir, Freundlich and Dubinin-Radushkevich models. The adsorption process was found to follow pseudo-first order kinetic model and also followed the intraparticle diffusion up to 60 minutes of contact time. The thermodynamic parameters suggest the spontaneous nature of adsorption

  17. INAA of toxic heavy metals in solid wastes from Indian cities

    International Nuclear Information System (INIS)

    Garg, A.N.; Ramakrishna, V.V.S.; Singh, V.

    1997-01-01

    Solid wastes and sewage sludges in metropolitan cities are potential health hazards due to toxic heavy metal pollutants. Sewage sludges from six Indian cities viz., Ahmedabad, Bikaner, Bombay, Calcutta, Jaipur, Kanpur and solid wastes from six different disposal sites of the capital city of Delhi have been analyzed for 26 elements (As, Au, Ba, Br, Co, Cr, Cs, Cu, Eu, Fe, Hg, Hf, K, La, Mg, Mn, Mo, Na, P, Rb, Sb, Sc, Se, Sr, Th and Zn) by employing instrumental neutron activation analysis (INAA). Sewage sludges from Bombay after different treatments (settled, digested, aerobic, anaerobic) along with several environmental SRMs were also analyzed. An attempt has been made to attribute the pollutant sources to the degree of urbanisation and industrialization of the city. Role of treatment processes in the removal/retention of heavy metals is discussed. (author)

  18. Metal recovery from municipal solid waste incineration bottom ash (MSWIBA): state of the art, potential and environmental benefits

    DEFF Research Database (Denmark)

    Allegrini, Elisa; Holtze, Maria S.; Astrup, Thomas Fruergaard

    Incineration has a central role in the waste management system in Denmark (e.g. 52% of the household waste) resulting in approximately 726000t of solid residues each year. However, the targets imposed by the Danish Waste Strategy and the increasing discussions about resource in waste raise an issue...... on resource losses through waste incineration. In this framework, this study provides actual data on the state of the art of the recovery of resource in MSWIBA in Denmark (i.e. metals), on the potential for further recovery and on the environmental benefits or burdens assessed through the Life Cycle...

  19. Perovskite–Ni composite: A potential route for management of radioactive metallic waste

    Energy Technology Data Exchange (ETDEWEB)

    Mahadik, Pooja Sawant; Sengupta, Pranesh, E-mail: sengupta@barc.gov.in; Halder, Rumu; Abraham, G.; Dey, G.K.

    2015-04-28

    Highlights: • Management of radioactive Ni based metallic wastes. • Microstructure of Ni/NiO–perovskite composite. • Interaction of Ni/NiO–perovskite composite with simulated high level waste glass melt. - Abstract: Management of nickel – based radioactive metallic wastes is a difficult issue. To arrest the release of hazardous material to the environment it is proposed to develop perovskite coating for the metallic wastes. Polycrystalline BaCe{sub 0.8}Y{sub 0.2}O{sub 3−δ} perovskite with orthorhombic structure has been synthesized by sol–gel route. Crystallographic analyses show, the perovskite belong to orthorhombic Pmcn space group at room temperature, and gets converted to orthorhombic Incn space group at 623 K, cubic Pm3m space group (with a = 4.434 Å) at 1173 K and again orthorhombic Pmcn space group at room temperature after cooling. Similar observations have been made from micro-Raman study as well. Microstructural studies of BaCe{sub 0.8}Y{sub 0.2}O{sub 3−δ}–NiO/Ni composites showed absence of any reaction product at the interface. This suggests that both the components (i.e. perovskite and NiO/Ni) of the composite are compatible to each other. Interaction of BaCe{sub 0.8}Y{sub 0.2}O{sub 3−δ}–NiO/Ni composites with simulated barium borosilicate waste glass melt also did not reveal any reaction product at the interfaces. Importantly, uranium from the waste glass melt was found to be partitioned within BaCe{sub 0.8}Y{sub 0.2}O{sub 3−δ} perovskite structure. It is therefore concluded that BaCe{sub 0.8}Y{sub 0.2}O{sub 3−δ} can be considered as a good coating material for management of radioactive Ni based metallic wastes.

  20. Informal e-waste recycling: environmental risk assessment of heavy metal contamination in Mandoli industrial area, Delhi, India.

    Science.gov (United States)

    Pradhan, Jatindra Kumar; Kumar, Sudhir

    2014-01-01

    Nowadays, e-waste is a major source of environmental problems and opportunities due to presence of hazardous elements and precious metals. This study was aimed to evaluate the pollution risk of heavy metal contamination by informal recycling of e-waste. Environmental risk assessment was determined using multivariate statistical analysis, index of geoaccumulation, enrichment factor, contamination factor, degree of contamination and pollution load index by analysing heavy metals in surface soils, plants and groundwater samples collected from and around informal recycling workshops in Mandoli industrial area, Delhi, India. Concentrations of heavy metals like As (17.08 mg/kg), Cd (1.29 mg/kg), Cu (115.50 mg/kg), Pb (2,645.31 mg/kg), Se (12.67 mg/kg) and Zn (776.84 mg/kg) were higher in surface soils of e-waste recycling areas compared to those in reference site. Level exceeded the values suggested by the US Environmental Protection Agency (EPA). High accumulations of heavy metals were also observed in the native plant samples (Cynodon dactylon) of e-waste recycling areas. The groundwater samples collected form recycling area had high heavy metal concentrations as compared to permissible limit of Indian Standards and maximum allowable limit of WHO guidelines for drinking water. Multivariate analysis and risk assessment studies based on total metal content explains the clear-cut differences among sampling sites and a strong evidence of heavy metal pollution because of informal recycling of e-waste. This study put forward that prolonged informal recycling of e-waste may accumulate high concentration of heavy metals in surface soils, plants and groundwater, which will be a matter of concern for both environmental and occupational hazards. This warrants an immediate need of remedial measures to reduce the heavy metal contamination of e-waste recycling sites.

  1. Heavy metal contamination of soil and water in the vicinity of an abandoned e-waste recycling site: implications for dissemination of heavy metals.

    Science.gov (United States)

    Wu, Qihang; Leung, Jonathan Y S; Geng, Xinhua; Chen, Shejun; Huang, Xuexia; Li, Haiyan; Huang, Zhuying; Zhu, Libin; Chen, Jiahao; Lu, Yayin

    2015-02-15

    Illegal e-waste recycling activity has caused heavy metal pollution in many developing countries, including China. In recent years, the Chinese government has strengthened enforcement to impede such activity; however, the heavy metals remaining in the abandoned e-waste recycling site can still pose ecological risk. The present study aimed to investigate the concentrations of heavy metals in soil and water in the vicinity of an abandoned e-waste recycling site in Longtang, South China. Results showed that the surface soil of the former burning and acid-leaching sites was still heavily contaminated with Cd (>0.39 mg kg(-1)) and Cu (>1981 mg kg(-1)), which exceeded their respective guideline levels. The concentration of heavy metals generally decreased with depth in both burning site and paddy field, which is related to the elevated pH and reduced TOM along the depth gradient. The pond water was seriously acidified and contaminated with heavy metals, while the well water was slightly contaminated since heavy metals were mostly retained in the surface soil. The use of pond water for irrigation resulted in considerable heavy metal contamination in the paddy soil. Compared with previous studies, the reduced heavy metal concentrations in the surface soil imply that heavy metals were transported to the other areas, such as pond. Therefore, immediate remediation of the contaminated soil and water is necessary to prevent dissemination of heavy metals and potential ecological disaster. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Perovskite-Ni composite: a potential route for management of radioactive metallic waste.

    Science.gov (United States)

    Mahadik, Pooja Sawant; Sengupta, Pranesh; Halder, Rumu; Abraham, G; Dey, G K

    2015-04-28

    Management of nickel - based radioactive metallic wastes is a difficult issue. To arrest the release of hazardous material to the environment it is proposed to develop perovskite coating for the metallic wastes. Polycrystalline BaCe0.8Y0.2O3-δ perovskite with orthorhombic structure has been synthesized by sol-gel route. Crystallographic analyses show, the perovskite belong to orthorhombic Pmcn space group at room temperature, and gets converted to orthorhombic Incn space group at 623K, cubic Pm3m space group (with a=4.434Å) at 1173K and again orthorhombic Pmcn space group at room temperature after cooling. Similar observations have been made from micro-Raman study as well. Microstructural studies of BaCe0.8Y0.2O3-δ-NiO/Ni composites showed absence of any reaction product at the interface. This suggests that both the components (i.e. perovskite and NiO/Ni) of the composite are compatible to each other. Interaction of BaCe0.8Y0.2O3-δ-NiO/Ni composites with simulated barium borosilicate waste glass melt also did not reveal any reaction product at the interfaces. Importantly, uranium from the waste glass melt was found to be partitioned within BaCe0.8Y0.2O3-δ perovskite structure. It is therefore concluded that BaCe0.8Y0.2O3-δ can be considered as a good coating material for management of radioactive Ni based metallic wastes. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Layered double hydroxides

    DEFF Research Database (Denmark)

    López Rayo, Sandra; Imran, Ahmad; Hansen, Hans Chr. Bruun

    2017-01-01

    A novel zinc (Zn) fertilizer concept based on Zn doped layered double hydroxides (Zn-doped Mg-Fe-LDHs) has been investigated. Zn-doped Mg-Fe-LDHs were synthetized, their chemical composition was analyzed and their nutrient release was studied in buffered solutions with different pH values. Uptake...

  4. Pollution control and resource reuse for alkaline hydrometallurgy of amphoteric metal hazardous wastes

    CERN Document Server

    Youcai, Zhao

    2017-01-01

    This book provides a comprehensive description of alkaline hydrometallurgy of amphoteric metal hazardous wastes. Topics focus on leaching of zinc and lead hazardous wastes, purification of leach solution of zinc and lead, electrowinning of zinc and lead from purified alkaline solutions, chemical reactions taking place in the production flowsheets, thermodynamic and spent electrolyte regeneration, alkaline hydrometallurgy of low-grade smithsonite ores, recovery of molybdenum and tungsten using ion flotation and solvent extraction processes and their application in chemical synthesis of Nb and Ta inorganic compounds, and industrial scale production of 1500-2000 t/a zinc powder using alkaline leaching–electrowinning processes. Processes described are cost-effective, generate lesser secondary pollutants, and have been applied widely in China. Readers that will find the book appealing include solid waste engineers, environmental managers, technicians, recycling coordinators, government officials, undergraduates ...

  5. Heavy metal uptake from municipal waste compost by the earthworm Eisenia foetida (Savigny 1826)

    Energy Technology Data Exchange (ETDEWEB)

    Fleckenstein, J.; Graff, O.

    1982-01-01

    The uptake of heavy metals and toxic elements by the adult earthworms Eisenia foetida kept in municipal waste compost for 55 and 104 days and by the juveniles was investigated. The uptake of Cu, Zn and Ni increased to constant levels, which appear to be regulated by the physiology of the earthworms. In contrary to this Cd, Hg and As continued to accumulate in the tissues of the earthworms throughout the exposure time. The Pb concentration ratio increased also, but was low (< 0.05). The living conditions for the earthworms in municipal waste compost were satisfactory but the results demonstrate that their use for biological conversion of waste compost to biomass for further animal nutrition is limited by the accumulation of cadmium and mercury.

  6. Barrier capacity of weathered coal mining wastes with respect to heavy metal and organic contaminants

    International Nuclear Information System (INIS)

    Twardowska, I.; Jarosinska, B.

    1992-01-01

    Some types of weathered, buffered coal mining wastes (CMW), being essentially heterogenous and complex mineralogical system of developed surface area, under certain conditions could be widely applicable for binding a variety of contaminants both inorganic in cationic or anionic form, and organic compounds. The experiments reported earlier, showed excellent Cr(VI)-binding capacity of CMW. In this paper, experiments on simultaneous removal of heavy metals Cr t , Cu 2+ , Zn 2+ and Cd 2+ from highly (pH 2.5) and mildly acidic solutions (pH 4.0), as well as of organic compounds and color reduction in leachate from solid industrial waste dump (foundry wastes) will be presented

  7. Manufacture and inspection of metal containers for the storage of waste contaminated with caesium-137

    International Nuclear Information System (INIS)

    Brito, M.J.D.; Moreira, M.S.

    1998-01-01

    Several stages are described of the design and manufacture of a prototype unit and 15 metal cylindrical containers for the storage of contaminated waste generated by the radiological accident of Goiania in 1987. The tasks involved technicians from the Nuclear Technology Development Centre (CDTN) of Belo Horizonte and the co-authors, who conducted inspections in the period between 10 March 1993 and 18 May 1993 at the foundry in Goiania. (author)

  8. Policy Statement: Clarification of the Dilution Prohibition and Combustion of Inorganic Metal-Bearing Hazardous Wastes for Land Disposal Restrictions

    Science.gov (United States)

    This memorandum sets out a Statement of Policy under the RCRA clarifying the application of the Land Disposal Restrictions (LDR) prohibition on dilution (see 40 CFR 268.3) to combustion of certain inorganic metal-bearing hazardous wastes.

  9. X-ray diffraction of the diminution in the concentration of heavy metals from industrial waste water sludge

    International Nuclear Information System (INIS)

    Carreno de Leon, M.C.

    1996-01-01

    We worked with an apparatus and process patented for Jaime Vite Torres, in the United States of America, for extracting simultaneously toxic and value metals from foundry sands. In this research, we used similar devices to remove toxic metals of waste water sludge. Generation of solid wastes including dangerous in 1992 in Mexico were 450,000 ton/day in accordance with the National Institut of Ecology (INE-SEDESOL 1992). With the apparatus and process of the present work we obtained two important points, whic are: a) the recovery of metals in solution which can be recycled and, b) an important reduction in the toxic of the wastes which one treated can be handled as normal waste with important savings. From among the metals which it is possible to recover one can mention among others: Au, Pt, Ag, Cr, Mn, Co, Pb, Al, Ni and others. (Author)

  10. Innovative approach for the valorization of useful metals from waste electric and electronic equipment (WEEE)

    Science.gov (United States)

    Soare, V.; Burada, M.; Dumitrescu, D. V.; Constantin, I.; Soare, V.; Popescu, A.-M. J.; Carcea, I.

    2016-08-01

    Waste electric and electronic equipment are an important secondary source of rare and precious metals and their processing through ecological technologies constitutes a major concern in the European Union and significantly contributes to the reduction of environmental pollution and to the preservation of valuable resources of nonferrous metals. The paper presents an innovative approach for the complex valorization of useful metals contained in WEEE. The method consists in the melting of WEEE in a furnace in a microwave field at temperatures of 1000 ÷1200°C, for the complete separation of the metallic fraction from the organic components. The gases resulting from the melting process were also treated/neutralized in a microwave environment and the obtained metallic bulk (multi-component alloy) was processed through combined hydrometallurgical and electrochemical methods. The major elements in the metallic bulk (Cu, Sn, Zn, Pb) were separated/recovered by anodic dissolution, respectively by leaching in nitric acid followed by cementation using various agents, or by electrodeposition. Depending on the electrochemical parameters, cathodic deposits consisting of Cu, with a purity higher than 99.9%, or of Cu-Sn and Cu-Sn-Zn alloys were obtained. Silver was valorized by leaching/precipitation with NaCl and the gold concentrated in the anodic slime will be recovered by thiourea extraction. The experiments performed demonstrate the possibility of ecological and efficient processing of WEEE in a microwave field and the recovery of nonferrous and precious metals through combined hydrometallurgical and electrochemical methods.

  11. Treatment of metallurgical wastes : recovery of metal values from smelter slags by pressure oxidative leaching

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y.; Perederiy, I.; Papangelakis, V.G. [Toronto Univ., ON (Canada). Dept. of Chemical Engineering and Applied Chemistry

    2008-07-01

    Vast quantities of slag are produced and dumped as waste by-products during the production of base metals by smelting operations. These slags contain large amounts of valuable metals which lead to a decrease in metal yield and, combined with the entrapped sulphur, pose a danger to the environment. The dissolution of fayalite is important for the selective recovery of valuable metals and the cleanup of slags in high pressure oxidative leaching. The nature of base metals and iron in solidified slag must be investigated in order to understand the mechanism of the process. This paper discussed the application of powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM) for the characterization of a smelter slag microstructure. The study used leaching tests with the same smelter slag to measure and monitor the results of leaching, including metal extraction levels, the extent of iron dissolution as well as impurity contents. The paper provided information on the experiment with particular reference to slag leaching, chemical analysis, and characterization. It was concluded that slag consists of several solid phases with base metal sulfide and oxide droplets entrapped in the fayalite matrix or silica regions. Therefore, nickel, copper, cobalt, and zinc need to be exposed either chemically or mechanically to promote their recovery. 21 refs., 4 tabs., 5 figs.

  12. Yucca Mountain project canister material corrosion studies as applied to the electrometallurgical treatment metallic waste form

    Energy Technology Data Exchange (ETDEWEB)

    Keiser, D.D.

    1996-11-01

    Yucca Mountain, Nevada is currently being evaluated as a potential site for a geologic repository. As part of the repository assessment activities, candidate materials are being tested for possible use as construction materials for waste package containers. A large portion of this testing effort is focused on determining the long range corrosion properties, in a Yucca Mountain environment, for those materials being considered. Along similar lines, Argonne National Laboratory is testing a metallic alloy waste form that also is scheduled for disposal in a geologic repository, like Yucca Mountain. Due to the fact that Argonne`s waste form will require performance testing for an environment similar to what Yucca Mountain canister materials will require, this report was constructed to focus on the types of tests that have been conducted on candidate Yucca Mountain canister materials along with some of the results from these tests. Additionally, this report will discuss testing of Argonne`s metal waste form in light of the Yucca Mountain activities.

  13. Enhanced bioleaching efficiency of metals from E-wastes driven by biochar

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shuhua; Zheng, Yue; Yan, Weifu; Chen, Lixiang [CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 (China); University of Chinese Academy of Sciences, Beijing, 100049 (China); Dummi Mahadevan, Gurumurthy [CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 (China); Zhao, Feng, E-mail: fzhao@iue.ac.cn [CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 (China)

    2016-12-15

    Electronic wastes (E-wastes) contain a huge amount of valuable metals that are worth recovering. Bioleaching has attracted widespread attention as an environment-friendly and low-cost technology for the recycling of E-wastes. To avoid the disadvantages of being time-consuming or having a relatively low efficiency, biochar with redox activity was used to enhance bioleaching efficiency of metals from a basic E-waste (i.e., printed circuit boards in this study). The role of biochar was examined through three basic processes: Carbon-mediated, Sulfur-mediated and Iron-mediated bioleaching pathways. Although no obvious enhancement of bioleaching performance was observed in the C-mediated and S-mediated systems, Fe-mediated bioleaching was significantly promoted by the participation of biochar, and its leaching time was decreased by one-third compared with that of a biochar-free system. By mapping the dynamic concentration of Fe(II) and Cu(II), biochar was proved to facilitate the redox action between Fe(II) to Fe(III), which resulted in effective leaching of Cu. Two dominant functional species consisting of Alicyclobacillus spp. and Sulfobacillus spp. may cooperate in the Fe-mediated bioleaching system, and the ratio of these two species was regulated by biochar for enhancing the efficiency of bioleaching. Hence, this work provides a method to improve bioleaching efficiency with low-cost solid redox media.

  14. Heavy metal contamination in soils and vegetables near an e-waste processing site, South China.

    Science.gov (United States)

    Luo, Chunling; Liu, Chuanping; Wang, Yan; Liu, Xiang; Li, Fangbai; Zhang, Gan; Li, Xiangdong

    2011-02-15

    Environmental pollution due to uncontrolled e-waste recycling activities has been reported in a number of locations of China. In the present study, metal pollution to the surrounding environment from a primitive e-waste processing facility was investigated. Soils at sites where e-waste is burned in the open air, those of surrounding paddy fields and vegetable gardens, as well as common vegetable samples were collected and analyzed for heavy metals. The results showed that the soils of former incineration sites had the highest concentrations of Cd, Cu, Pb, and Zn with mean values of 17.1, 11,140, 4500, and 3690 mg kg(-1), respectively. The soils of nearby paddy fields and vegetable gardens also had relatively high concentrations of Cd and Cu. In the edible tissues of vegetables, the concentrations of Cd and Pb in most samples exceeded the maximum level permitted for food in China. Sequential leaching tests revealed that the Cu, Pb, and Zn were predominantly associated with the residual fraction, followed by the carbonate/specifically adsorbed phases with the exception of Cd, which was mainly in the extractable form in paddy fields and vegetable soils. The data showed that uncontrolled e-waste processing operations caused serious pollution to local soils and vegetables. The cleaning up of former incineration sites should be a priority in any future remediation program. Copyright © 2010 Elsevier B.V. All rights reserved.

  15. Enhanced bioleaching efficiency of metals from E-wastes driven by biochar

    International Nuclear Information System (INIS)

    Wang, Shuhua; Zheng, Yue; Yan, Weifu; Chen, Lixiang; Dummi Mahadevan, Gurumurthy; Zhao, Feng

    2016-01-01

    Electronic wastes (E-wastes) contain a huge amount of valuable metals that are worth recovering. Bioleaching has attracted widespread attention as an environment-friendly and low-cost technology for the recycling of E-wastes. To avoid the disadvantages of being time-consuming or having a relatively low efficiency, biochar with redox activity was used to enhance bioleaching efficiency of metals from a basic E-waste (i.e., printed circuit boards in this study). The role of biochar was examined through three basic processes: Carbon-mediated, Sulfur-mediated and Iron-mediated bioleaching pathways. Although no obvious enhancement of bioleaching performance was observed in the C-mediated and S-mediated systems, Fe-mediated bioleaching was significantly promoted by the participation of biochar, and its leaching time was decreased by one-third compared with that of a biochar-free system. By mapping the dynamic concentration of Fe(II) and Cu(II), biochar was proved to facilitate the redox action between Fe(II) to Fe(III), which resulted in effective leaching of Cu. Two dominant functional species consisting of Alicyclobacillus spp. and Sulfobacillus spp. may cooperate in the Fe-mediated bioleaching system, and the ratio of these two species was regulated by biochar for enhancing the efficiency of bioleaching. Hence, this work provides a method to improve bioleaching efficiency with low-cost solid redox media.

  16. Evaluation of physical, chemical and heavy metal concentration of food waste composting

    Directory of Open Access Journals (Sweden)

    Abdul Kadir Aeslina

    2017-01-01

    Full Text Available In this study, food waste composting with rice husk and coconut fibre as compost medium were carried out. Two types of different fermentation liquids were prepared which were fermented liquid (banana peel and fermented liquid from fermented soybeans. During the composting process, a compost samples for a twenty week duration at an interval time of two weeks. Among the physico-chemical parameters that were tested were temperature, moisture content, pH value, Total Nitrogen, Total Phosphorous, Potassium and Total Organic Carbon and Carbon Nitrogen ratio. Heavy metals such as copper, cadmium, lead, nickel and arsenic were observed and analysed. From this study, it was found that, the temperature increased during the thermophilic phase while there was gradually increase of Total Nitrogen, Total Phosphorous and Potassium from the beginning till the end of the composting process. It was also found that the total organic carbon (TOC and the carbon nitrogen ratio decreased significantly during the decomposition process. Traces amounts of heavy metals were also detected and remains below the standard Malaysian Environmental regulations. It was concluded that, the composting process was faster with processed food waste followed by combination of processed food waste and raw. Raw food waste were demonstrated the lowest degradation rate.

  17. Metals in coastal zones impacted with urban and industrial wastes: Insights on the metal accumulation pattern in fish species

    Science.gov (United States)

    La Colla, Noelia S.; Botté, Sandra E.; Marcovecchio, Jorge E.

    2018-05-01

    The pollution of aquatic environments is a worldwide problem of difficult solution since these areas are used for the disposal and dilution of anthropogenic wastes. This study evaluated the concentrations of Cd, Cu, Ni and Zn in the gills, liver and muscle tissues of six economically important fish species from the Bahía Blanca estuary in Argentina, a coastal environment that is under anthropogenic pressure. Metal contents in 147 fish samples were determined by digestion and a subsequent analysis with an ICP OES. The concentrations (μg/g, wet weight) of each metal in the fish tissues ranged from below the limit of detection for the four metals to 5.2 in the case of Cd, 340 for Cu, 20 for Ni, and 101 for Zn. The results suggested that metal burden in fishes varied with the species and metal elements, with Cd, Cu and Zn mean maximum accumulation towards the liver tissue. Ni showed a high number of samples with concentrations below the limit of detection. Among species, Cynoscion guatucupa was found to have the highest concentrations of Cu and Zn in the liver tissues, whereas the gills and liver tissues of Mustelus schmitti showed the lowest levels of Ni and Zn. As regards the human health risks, two samples of muscle tissue belonging to C. guatucupa reached to Cd levels that exceeded the permissible levels for human consumption. Moreover, the estimated daily intakes calculated suggest that people would not experience significant health risks from the intake of individual metals through fish consumption.

  18. Capture of organic iodides from nuclear waste by metal-organic framework-based molecular traps.

    Science.gov (United States)

    Li, Baiyan; Dong, Xinglong; Wang, Hao; Ma, Dingxuan; Tan, Kui; Jensen, Stephanie; Deibert, Benjamin J; Butler, Joseph; Cure, Jeremy; Shi, Zhan; Thonhauser, Timo; Chabal, Yves J; Han, Yu; Li, Jing

    2017-09-07

    Effective capture of radioactive organic iodides from nuclear waste remains a significant challenge due to the drawbacks of current adsorbents such as low uptake capacity, high cost, and non-recyclability. We report here a general approach to overcome this challenge by creating radioactive organic iodide molecular traps through functionalization of metal-organic framework materials with tertiary amine-binding sites. The molecular trap exhibits a high CH 3 I saturation uptake capacity of 71 wt% at 150 °C, which is more than 340% higher than the industrial adsorbent Ag 0 @MOR under identical conditions. These functionalized metal-organic frameworks also serve as good adsorbents at low temperatures. Furthermore, the resulting adsorbent can be recycled multiple times without loss of capacity, making recyclability a reality. In combination with its chemical and thermal stability, high capture efficiency and low cost, the adsorbent demonstrates promise for industrial radioactive organic iodides capture from nuclear waste. The capture mechanism was investigated by experimental and theoretical methods.Capturing radioactive organic iodides from nuclear waste is important for safe nuclear energy usage, but remains a significant challenge. Here, Li and co-workers fabricate a stable metal-organic framework functionalized with tertiary amine groups that exhibits high capacities for radioactive organic iodides uptake.

  19. Capture of organic iodides from nuclear waste by metal-organic framework-based molecular traps

    KAUST Repository

    Li, Baiyan

    2017-09-01

    Effective capture of radioactive organic iodides from nuclear waste remains a significant challenge due to the drawbacks of current adsorbents such as low uptake capacity, high cost, and non-recyclability. We report here a general approach to overcome this challenge by creating radioactive organic iodide molecular traps through functionalization of metal-organic framework materials with tertiary amine-binding sites. The molecular trap exhibits a high CH3I saturation uptake capacity of 71 wt% at 150 °C, which is more than 340% higher than the industrial adsorbent Ag0@MOR under identical conditions. These functionalized metal-organic frameworks also serve as good adsorbents at low temperatures. Furthermore, the resulting adsorbent can be recycled multiple times without loss of capacity, making recyclability a reality. In combination with its chemical and thermal stability, high capture efficiency and low cost, the adsorbent demonstrates promise for industrial radioactive organic iodides capture from nuclear waste. The capture mechanism was investigated by experimental and theoretical methods.Capturing radioactive organic iodides from nuclear waste is important for safe nuclear energy usage, but remains a significant challenge. Here, Li and co-workers fabricate a stable metal-organic framework functionalized with tertiary amine groups that exhibits high capacities for radioactive organic iodides uptake.

  20. Valorization of mine rejects and industrial wastes for the recovery of some strategic and critical metals

    International Nuclear Information System (INIS)

    Sreenivas, T.; Dey, G K.; Anand Rao, K.

    2017-01-01

    Strategic and critical metals (SCM) resources form important components in safety and security design of any country. Uneven distribution of SCM resources as well as lack of technical expertise in manufacture of end-products makes many nations vulnerable to external pulls and pressures. India is making determined bid to surmount these difficulties by constantly upgrading its scientific and engineering expertise to address issues related to resources and materials manufacturing technologies. It is a well known fact that India is a resource starved country with respect to many of the strategic and critical metals (SCM). The demand for the SCM is met mostly by import of finished products and to a lesser extent by recycle of used products. In these days of growing inclination towards 'sustainable development' valorization of industrial waste for securing valuable metals including those of SCM category is worth pursuing, more so for a country like India. With this premise, we present in this paper representative case studies which depict technical feasibility of using industrial waste as a source for some important SCM, namely Nd, Y, Co and W. The wastes used for valorization are the mine tailings or rejects of different ores like copper, gold, uranium and fly ash generated from a coal-fired thermal power plant. (author)

  1. Persimmon leaf bio-waste for adsorptive removal of heavy metals from aqueous solution.

    Science.gov (United States)

    Lee, Seo-Yun; Choi, Hee-Jeong

    2018-03-01

    The aim of this study was to investigate heavy metal removal using waste biomass adsorbent, persimmon leaves, in an aqueous solution. Persimmon leaves, which are biomaterials, have a large number of hydroxyl groups and are highly suitable for removal of heavy metals. Therefore, in this study, we investigated the possibility of removal of Cu, Pb, and Cd in aqueous solution by using raw persimmon leaves (RPL) and dried persimmon leaves (DPL). Removal of heavy metals by RPL and DPL showed that DPL had a 10%-15% higher removal than RPL, and the order of removal efficiency was found to be Pb > Cu > Cd. The pseudo-second order model was a better fit to the heavy metal adsorption experiments using RPL and DPL than the pseudo-first order model. The adsorption of Cu, Pb, and Cd by DPL was more suitable with the Freundlich isothermal adsorption and showed an ion exchange reaction which occurred in the uneven adsorption surface layer. The maximum adsorption capacity of Cu, Pb, and Cd was determined to be 19.42 mg/g, 22.59 mg/g, and 18.26 mg/g, respectively. The result of the adsorption experiments showed that the n value was higher than 2 regardless of the dose, indicating that the heavy metal adsorption on DPL was easy. In the thermodynamic experiment, ΔG° was a negative value, and ΔH° and ΔS° were positive values. It can be seen that the heavy metal adsorption process using DPL was spontaneous in nature and was an endothermic process. Moreover, as the temperature increased, the adsorption increased, and the affinity of heavy metal adsorption to DPL was very good. This experiment, in which heavy metals are removed using the waste biomass of persimmon leaves is an eco-friendly new bioadsorbent method because it can remove heavy metals without using chemicals while utilizing waste recycling. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Selective chelation-supercritical fluid extraction of metal ions from waste materials

    International Nuclear Information System (INIS)

    Wai, C.N.; Laintz, K.E.; Yonker, C.R.

    1993-01-01

    The removal of toxic organics, metals, and radioisotopes from solids or liquids is a major concern in the treatment of industrial and nuclear wastes. For this reason, developing methods for selective separation of toxic metals and radioactive materials from solutions of complex matrix is an important problem in environmental research. Recent developments indicate supercritical fluids are good solvents for organic compounds. Many gases become supercritical fluids under moderate temperatures and pressures. For example, the critical temperature and pressure of carbon dioxide are 31 degrees C and 73 atm, respectively. The high diffusivity, low viscosity, and T-P dependence of solvent strength are some attractive properties of supercritical fluid extraction (SFE). Since CO 2 offers the additional benefits of stability and non-toxicity, the SFE technique avoids generation of organic liquid waste and exposure of personnel to toxic solvents. While direct extraction of metal ions by supercritical fluids is highly inefficient, these ions when complexed with organic ligands become quite soluble in supercritical fluids. Specific ligands can be used to achieve selective extraction of metal ions in this process. After SFE, the fluid phase can be depressurized for precipitation of the metal chelates and recycled. The ligand can also be regenerated for repeated use. The success of this selective chelation-supercritical fluid extraction (SC-SFE) process depends on a number of factors including the efficiencies of the selective chelating agents, solubilities of metal chelates in supercritical fluids, rate of extraction, ease of regeneration of the ligands, etc. In this report, the authors present recent results on the studies of the solubilities of metal chelates in supercritical CO 2 , experimental ions from aqueous solution, and the development of selective chelating agents (ionizable crown ethers) for the extraction of lanthanides and actinides

  3. Metals removal from spent salts

    Science.gov (United States)

    Hsu, Peter C.; Von Holtz, Erica H.; Hipple, David L.; Summers, Leslie J.; Brummond, William A.; Adamson, Martyn G.

    2002-01-01

    A method and apparatus for removing metal contaminants from the spent salt of a molten salt oxidation (MSO) reactor is described. Spent salt is removed from the reactor and analyzed to determine the contaminants present and the carbonate concentration. The salt is dissolved in water, and one or more reagents may be added to precipitate the metal oxide and/or the metal as either metal oxide, metal hydroxide, or as a salt. The precipitated materials are filtered, dried and packaged for disposal as waste or can be immobilized as ceramic pellets. More than about 90% of the metals and mineral residues (ashes) present are removed by filtration. After filtration, salt solutions having a carbonate concentration >20% can be spray-dried and returned to the reactor for re-use. Salt solutions containing a carbonate concentration ion exchange column, which yields salt solutions that contain less than 1.0 ppm of contaminants.

  4. The concentrations of trace metals in plants from phosphogypsum waste heap in Wiślinka, northern Poland

    Directory of Open Access Journals (Sweden)

    Boryło A.

    2013-04-01

    Full Text Available The aim of this work was determination of trace metals (Pb, Zn, Ni, Cu and Fe in different plants collected in the vicinity of phosphogypsum waste heap in Wiślinka (northern Poland. The concentrations of trace metals were determined by two methods: AAS (atomic absorption spectrometry and OES-ICP (atomic emission spectrometry with inductively coupled plasma. Enhanced levels of iron were observed in all the analyzed samples. This fact can be explained by the higher content of iron in the groundwaters of Žuławy Wiślane, where concentration of iron was 60 mg/l. The trace metals concentrations in plant samples from phosphogypsum waste heap recorded in this study are generally higher than in control sites. In this study the relationship is shown between atmospheric trace metals deposition and elevated trace metals element concentrations in plants and topsoils, especially in the vicinity of phoshpogypsum waste heap.

  5. METAL TOLERANCE ANALYSIS OF MICROFUNGI ISOLATED FROM METAL CONTAMINATED SOIL AND WASTE WATER

    Directory of Open Access Journals (Sweden)

    Mathan Jayaraman

    2014-08-01

    Full Text Available The influence of Cr6+, Pb2+, Cu2+, Ni2+, Zn2+ and Cd2+ on the development of 24 fungi was investigated for Metal Tolerance Index (MTI at 1mg ml-1 Cr6+, Pb2+, Cu2+, Ni2+, Zn2+ and Cd2+ concentrations and also for Minimum Inhibitory Concentration (MIC. The MIC ranged from 0.5 to 1.5 mg ml-1 depending on the isolate Aspergillus, Fusarium and Penicillium sp. were tested for their metal tolerance index. Out of these Aspergillus flavus (ED4 shows a better tolerance index of 0.80 Cr6+, 0.72 for Pb2+ , 0.63 for Cu2+, 0.58 for Ni2+, 0.46 for Zn2+ and 0.60 Cd2+ for MIC value for the removal of heavy metals from contaminated soil and wastewaters.

  6. Sources of heavy metal contamination in Swedish wood waste used for combustion

    International Nuclear Information System (INIS)

    Krook, J.; Martensson, A.; Eklund, M.

    2006-01-01

    In this paper, wood waste (RWW) recovered for heat production in Sweden was studied. Previous research has concluded that RWW contains elevated amounts of heavy metals, causing environmental problems during waste management. This study extends previous work on RWW by analysing which pollution sources cause this contamination. Using existing data on the metal contents in various materials, and the amounts of these materials in RWW, the share of the elevated amounts of metals in RWW that these materials explain was quantified. Six different materials occurring in RWW were studied and the results show that they explain from 70% to 100% of the amounts of arsenic, chromium, lead, copper and zinc in RWW. The most important materials contributing to contamination of RWW are surface-treated wood, industrial preservative-treated wood, plastic and galvanised fastening systems. These findings enable the development and evaluation of strategies aiming to decrease pollution and resource loss from handling RWW. It is argued that source separation and measures taken further downstream from the generation site, such as treatment, need to be combined to substantially decrease the amount of heavy metals in RWW

  7. Investigation of heavy metal partitioning influenced by flue gas moisture and chlorine content during waste incineration.

    Science.gov (United States)

    Li, Qinghai; Meng, Aihong; Jia, Jinyan; Zhang, Yanguo

    2010-01-01

    The impact of moisture on the partitioning of the heavy metals including Pb, Zn, Cu and Cd in municipal solid waste (MSW) was studied in a laboratory tubular furnace. A thermodynamic investigation using CHEMKIN software was performed to compare the experimental results. Simulated waste, representative of typical MSW with and without chlorine compounds, was burned at the background temperature of 700 and 950 degrees C, respectively. In the absence of chlorine, the moisture content has no evident effect on the volatility of Pb, Zn and Cu at either 700 or 950 degrees C, however, as flue gas moisture increasing the Cd distribution in the bottom ash increased at 700 degrees C and reduced at 950 degrees C, respectively. In the presence of chlorine, the flue gas moisture reduced the volatility of Pb, Zn and Cu due to the transformation of the more volatile metal chlorides into less volatile metal oxides, and the reduction became significant as chlorine content increase. For Cd, the chlorine promotes its volatility through the formation of more volatile CdCl2. As a result, the increased moisture content increases the Pb, Zn, Cu and Cd concentrations in the bottom ash, which limits the utilization of the bottom ash as a construction material. Therefore, in order to accumulate heavy metals into the fly ash, MSW should be dried before incineration.

  8. Metal recovery by bioleaching of sulfidic mining wastes — Application to a European case study

    Science.gov (United States)

    Guézennec, A. G.; Jacob, J.; Joulian, C.; Dupraz, S.; Menard, Y.; d'Hugues, P.

    The non-energy extractive industry (NEEI) of the EU-25 generated a direct turnover of about €40 billion, and provided employment to about 250000 people in 16629 companies in 2004. The use of primary raw materials in the production of other branches of EU industry means they have a central role in guaranteeing industrial and economic sustainability. Nevertheless current demand exceeds production, and so the EU is heavily dependent on minerals and metals imports. In this context of securing access to metals, turning mining wastes into new resources of currently unexploited valuable metals is an important challenge. The mining wastes can contain base and precious metals, but also metalloids and rare earth elements that are nowadays considered as highly critical for the industrial development of the European Union. Nevertheless, the development of alternative routes to conventional processing is still required in order to decrease the cost associated to the treatment of these unconventional resources which are more complex in composition and with lower grades.

  9. A simple scheme to determine potential aquatic metal toxicity from mining wastes

    Science.gov (United States)

    Wildeman, T.R.; Smith, K.S.; Ranville, J.F.

    2007-01-01

    A decision tree (mining waste decision tree) that uses simple physical and chemical tests has been developed to determine whether effluent from mine waste material poses a potential toxicity threat to the aquatic environment. For the chemical portion of the tree, leaching tests developed by the United States Geological Survey, the Colorado Division of Minerals and Geology (Denver, CO), and a modified 1311 toxicity characteristic leaching procedure (TCLP) test of the United States Environmental Protection Agency have been extensively used as a surrogate for readily available metals that can be released into the environment from mining wastes. To assist in the assessment, element concentration pattern graphs (ECPG) are produced that compare concentrations of selected groups of elements from the three leachates and any water associated with the mining waste. The MWDT makes a distinction between leachates or waters with pH less than or greater than 5. Generally, when the pH values are below 5, the ECPG of the solutions are quite similar, and potential aquatic toxicity from cationic metals, such as Pb, Cu, Zn, Cd, and Al, is assumed. Below pH 5, these metals are mostly dissolved, generally are not complexed with organic or inorganic ligands, and hence are more bioavailable. Furthermore, there is virtually no carbonate alkalinity at pH less than 5. All of these factors promote metal toxicity to aquatic organisms. On the other hand, when the pH value of the water or the leachates is above 5, the ECPG from the solutions are variable, and inferred aquatic toxicity depends on factors in addition to the metals released from the leaching tests. Hence, leachates and waters with pH above 5 warrant further examination of their chemical composition. Physical ranking criteria provide additional information, particularly in areas where waste piles exhibit similar chemical rankings. Rankings from physical and chemical criteria generally are not correlated. Examples of how this

  10. Assessing metal contamination from construction and demolition (C&D) waste used to infill wetlands: using Deroceras reticulatum (Mollusca: Gastropoda).

    Science.gov (United States)

    Staunton, John A; Mc Donnell, Rory J; Gormally, Michael J; Williams, Chris D; Henry, Tiernan; Morrison, Liam

    2014-11-01

    Large quantities of construction and demolition waste (C&D) are produced globally every year, with little known about potential environmental impacts. In the present study, the slug, Deroceras reticulatum (Mollusca: Gastropoda) was used as the first biomonitor of metals (Ag, As, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, Se, Ti, Tl, V and Zn) on wetlands post infilling with construction and demolition (C&D) waste. The bioaccumulation of As, Ba, Cd, Co, Sb, Se and Tl were found to be significantly elevated in slugs collected on C&D waste when compared to unimproved pastures (control sites), while Mo, Se and Sr had significantly higher concentrations in slugs collected on C&D waste when compared to known contaminated sites (mining locations), indicating the potential hazardous nature of C&D waste to biota. Identifying exact sources for these metals within the waste can be problematic, due to its heterogenic nature. Biomonitors are a useful tool for future monitoring and impact studies, facilitating policy makers and regulations in other countries regarding C&D waste infill. In addition, improving separation of C&D waste to allow increased reuse and recycling is likely to be effective in reducing the volume of waste being used as infill, subsequently decreasing potential metal contamination.

  11. Environmental effects of heavy metals derived from the e-waste recycling activities in China: a systematic review.

    Science.gov (United States)

    Song, Qingbin; Li, Jinhui

    2014-12-01

    As the world's leading manufacturing country, China has become the largest dumping ground for e-waste, resulting in serious pollution of heavy metals in China. This study reviews recent studies on environmental effects of heavy metals from the e-waste recycling sites in China, especially Taizhou, Guiyu, and Longtang. The intensive uncontrolled processing of e-waste in China has resulted in the release of large amounts of heavy metals in the local environment, and caused high concentrations of metals to be present in the surrounding air, dust, soils, sediments and plants. Though the pollution of many heavy metals was investigated in the relevant researches, the four kinds of heavy metals (Cu, Pb, Cd and Cr) from e-waste recycling processes attracted more attention. The exceedance of various national and international standards imposed negative effects to the environment, which made the local residents face with the serious heavy metal exposure. In order to protect the environment and human health, there is an urgent need to control and monitor the informal e-waste recycling operations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Formal recycling of e-waste leads to increased exposure to toxic metals: an occupational exposure study from Sweden.

    Science.gov (United States)

    Julander, Anneli; Lundgren, Lennart; Skare, Lizbet; Grandér, Margaretha; Palm, Brita; Vahter, Marie; Lidén, Carola

    2014-12-01

    Electrical and electronic waste (e-waste) contains multiple toxic metals. However, there is currently a lack of exposure data for metals on workers in formal recycling plants. The objective of this study was to evaluate workers' exposure to metals, using biomarkers of exposure in combination with monitoring of personal air exposure. We assessed exposure to 20 potentially toxic metals among 55 recycling workers and 10 office workers at three formal e-waste recycling plants in Sweden. Workers at two of the plants were followed-up after 6 months. We collected the inhalable fraction and OFC (37-mm) fraction of particles, using personal samplers, as well as spot samples of blood and urine. We measured metal concentrations in whole blood, plasma, urine, and air filters using inductively coupled plasma-mass spectrometry following acid digestion. The air sampling indicated greater airborne exposure, 10 to 30 times higher, to most metals among the recycling workers handling e-waste than among the office workers. The exposure biomarkers showed significantly higher concentrations of chromium, cobalt, indium, lead, and mercury in blood, urine, and/or plasma of the recycling workers, compared with the office workers. Concentrations of antimony, indium, lead, mercury, and vanadium showed close to linear associations between the inhalable particle fraction and blood, plasma, or urine. In conclusion, our study of formal e-waste recycling shows that workers performing recycling tasks are exposed to multiple toxic metals. Copyright © 2014. Published by Elsevier Ltd.

  13. REPORT ON QUALITATIVE VALIDATION EXPERIMENTS USING LITHIUM-ALUMINUM LAYERED DOUBLE-HYDROXIDES FOR THE REDUCTION OF ALUMINUM FROM THE WASTE TREATMENT PLANT FEEDSTOCK

    International Nuclear Information System (INIS)

    Huber, H.J.; Duncan, J.B.; Cooke, G.A.

    2010-01-01

    A process for removing aluminum from tank waste simulants by adding lithium and precipitating Li-Al-dihydroxide (Lithiumhydrotalcite, (LiAl 2 (OH) 6 ) + X - ) has been verified. The tests involved a double-shell tank (DST) simulant and a single-shell tank (SST) simulant. In the case of the DST simulant, the product was the anticipated Li-hydrotalcite. For the SST simulant, the product formed was primarily Li-phosphate. However, adding excess Li to the solution did result in the formation of traces of Li-hydrotalcite. The Li-hydrotalcite from the DST supernate was an easily filterable solid. After four water washes the filter cake was a fluffy white material made of < 100 (micro)m particles made of smaller spheres. These spheres are agglomerates of ∼ 5 (micro)m diameter platelets with < 1 (micro)m thickness. Chemical and mineralogical analyses of the filtrate, filter cake, and wash waters indicate a removal of 90+ wt% of the dissolved Al for the DST simulant. For the SST simulant, the main competing reaction to the formation of lithium hydrotalcite appears to be the formation of lithium phosphate. In case of the DST simulant, phosphorus co-precipitated with the hydrotalcite. This would imply the added benefit of the removal of phosphorus along with aluminum in the pre-treatment part of the waste treatment and immobilization plant (WTP). For this endeavor to be successful, a serious effort toward process parameter optimization is necessary. Among the major issues to be addressed are the dependency of the reaction yield on the solution chemistry, as well as residence times, temperatures, and an understanding of particle growth.

  14. Electronic spectra of anions intercalated in layered double hydroxides

    Indian Academy of Sciences (India)

    Transition metal complexes intercalated in layered double hydroxides have a different electronic structure as compared to their free state owing to their confinement within the interlayer gallery. UV–Vis absorptions of the intercalated complex anions show a significant shift as compared to their free state. The ligand to metal ...

  15. Multiple antibiotic resistances in metal tolerant E. coli from hospital waste water.

    Science.gov (United States)

    Alam, Manzar; Imran, Mohd

    2014-01-01

    Study of antibiotic resistance was done among the metal tolerant E. coli isolates from hospital wastewater at Lucknow city. Metal tolerance was determined in terms of visible growth on metal amended plates at their varying concentrations. MICs were also determined among all metal tolerant E. coli isolates. All the isolates showed their MIC in between 100-2000 µg/ml while maximum isolates demonstrated their MICs at 400, 800 and 1600 µg/ml against all the metal tested. 23.07% of the isolates showed their MIC at 2000 µg/ml against Ni(3+). Multiple antibiotic resistances were recorded among all the metal resistant E.coli isolates. A high level of resistance was observed against Methicillin (86.53%) followed by penicillin (73.07%), Cephradin (57.69%), Rifampicin (34.61%), Erythromycin (26.92%), Nalidixic acids (25%), Chloramphenicol (3.84%) and least to Gentamycine (1.92%). Streptomycin was recorded most effective against E.coli isolates among the entire antibiotic tested. Antimicrobial resistance observed among the bacteria from the aquatic system contaminated with hospital wastes may be threatful for the environment and public health both.

  16. Leaching behavior of heavy metals from municipal solid wastes incineration (MSWI) fly ash used in concrete

    International Nuclear Information System (INIS)

    Shi Huisheng; Kan Lili

    2009-01-01

    The characteristics of municipal solid waste incineration (MSWI) fly ash, surface leaching toxicity and successive leaching concentration of heavy metals from MSWI fly ash-cement hardened pastes were studied. And, the relationships between leaching concentrations of heavy metals and leaching time were also discussed. Experimental results showed that immobilization effect of cement on MSWI fly ash is good. Even if MSWI fly ash-cement hardened pastes were damaged, the leaching toxicity is still in a safety range. In early leaching stage, the surface leaching rate is relatively a little high, up to 10 -5 -10 -4 cm d -1 order of magnitude, in the later time of leaching, its rate rapidly declined, down to 10 -7 . Most of leached heavy metals are produced at early ages. The leaching concentration of heavy metals and leaching time has strong positive relationships. In factual utilizing circumstances, heavy metals' leaching from MSWI fly ash-cement hardened pastes is a very slow and gradually diluting process. The leaching toxicity of heavy metals is far lower than that of the National Standard of China, and minimum harmful matters can be contained and released in the environment. Reusing of MSWI fly ash as partial replacement for cement in concrete mixes is potentially feasible.

  17. Recycling of non-metallic fractions from waste electrical and electronic equipment (WEEE): a review.

    Science.gov (United States)

    Wang, Ruixue; Xu, Zhenming

    2014-08-01

    The world's waste electrical and electronic equipment (WEEE) consumption has increased incredibly in recent decades, which have drawn much attention from the public. However, the major economic driving force for recycling of WEEE is the value of the metallic fractions (MFs). The non-metallic fractions (NMFs), which take up a large proportion of E-wastes, were treated by incineration or landfill in the past. NMFs from WEEE contain heavy metals, brominated flame retardant (BFRs) and other toxic and hazardous substances. Combustion as well as landfill may cause serious environmental problems. Therefore, research on resource reutilization and safe disposal of the NMFs from WEEE has a great significance from the viewpoint of environmental protection. Among the enormous variety of NMFs from WEEE, some of them are quite easy to recycle while others are difficult, such as plastics, glass and NMFs from waste printed circuit boards (WPCBs). In this paper, we mainly focus on the intractable NMFs from WEEE. Methods and technologies of recycling the two types of NMFs from WEEE, plastics, glass are reviewed in this paper. For WEEE plastics, the pyrolysis technology has the lowest energy consumption and the pyrolysis oil could be obtained, but the containing of BFRs makes the pyrolysis recycling process problematic. Supercritical fluids (SCF) and gasification technology have a potentially smaller environmental impact than pyrolysis process, but the energy consumption is higher. With regard to WEEE glass, lead removing is requisite before the reutilization of the cathode ray tube (CRT) funnel glass, and the recycling of liquid crystal display (LCD) glass is economically viable for the containing of precious metals (indium and tin). However, the environmental assessment of the recycling process is essential and important before the industrialized production stage. For example, noise and dust should be evaluated during the glass cutting process. This study could contribute

  18. Sample preparation of waste water to determine metallic contaminants by X-ray fluorescence spectroscopy

    International Nuclear Information System (INIS)

    Gonzalez Olivos, Javier.

    1987-01-01

    Trace X-ray fluorescence spectroscopy analysis in liquid samples is preceded by sample preparation, which usually consists in the precipitation of the metallic ions and concentration over a thin cellulose filter. The samples preparation of waste water by this method is not efficient, due to the great amount of organic and insoluble matter that they contain. The purpose of this work was to determine the optimal value of pH in order to adsorbe all the insoluble matter contained in a waste water sample in the activated charcoal, so that the metallic ions could be precipitated and concentrated on a thin filter and determinated by X-ray fluorescence spectroscopy. A survey about the adsorption of some ions in activated charcoal in function of the pH was made for the following: Cr 3+ , Fe 3+ , Ni 2+ , Cu 2+ , Zn 2+ , Se 2+ , Hg 2+ , and Pb 2+ . It was observed that at pH 0, the ions are not adsorbed, but Cu 2+ and Zn 2+ are adsorbed in small amount; at pH 14, the ions are adsorbed, excluding Se, which is not adsorbed at any value of pH. If a waste water sample is treated at pH 0 with activated charcoal to adsorbe the organic and insoluble matter, most of the metallic ions are not adsorbed by the activated charcoal and could be precipitated with APDC (ammonium 1-pirrolidine dithio carbamate salt) and concentrated on a thin filter. The analysis of the metallic ions contained on the filter and those adsorbed in the activated charcoal by X-ray fluorescence spectroscopy, gave the total amount of the ions in the sample. (author)

  19. 40 CFR 62.14103 - Emission limits for municipal waste combustor metals, acid gases, organics, and nitrogen oxides.

    Science.gov (United States)

    2010-07-01

    ... combustor metals, acid gases, organics, and nitrogen oxides. 62.14103 Section 62.14103 Protection of... combustor metals, acid gases, organics, and nitrogen oxides. (a) The emission limits for municipal waste... nitrogen oxides in excess of the emission limits listed in table 2 of this subpart for affected facilities...

  20. 40 CFR 60.33b - Emission guidelines for municipal waste combustor metals, acid gases, organics, and nitrogen oxides.

    Science.gov (United States)

    2010-07-01

    ... combustor metals, acid gases, organics, and nitrogen oxides. 60.33b Section 60.33b Protection of Environment..., acid gases, organics, and nitrogen oxides. (a) The emission limits for municipal waste combustor metals... oxygen. (d) For approval, a State plan shall include emission limits for nitrogen oxides at least as...

  1. 40 CFR 60.52b - Standards for municipal waste combustor metals, acid gases, organics, and nitrogen oxides.

    Science.gov (United States)

    2010-07-01

    ... metals, acid gases, organics, and nitrogen oxides. 60.52b Section 60.52b Protection of Environment... § 60.52b Standards for municipal waste combustor metals, acid gases, organics, and nitrogen oxides. (a... (total mass), corrected to 7 percent oxygen. (d) The limits for nitrogen oxides are specified in...

  2. Decreased vaccine antibody titers following exposure to multiple metals and metalloids in e-waste-exposed preschool children

    NARCIS (Netherlands)

    Lin, Xinjiang; Xu, Xijin; Zeng, Xiang; Xu, Long; Zeng, Zhijun; Huo, Xia

    We explored acquired immunity resulting from vaccination in 3 to 7-year-old children, chronically exposed to multiple heavy metals and metalloids, in an e-waste recycling area (Guiyu, China). Child blood levels of ten heavy metals and metalloids, including lead (Pb), arsenic (As), mercury (Hg),

  3. Mesoporous layer-by-layer ordered nanohybrids of layered double hydroxide and layered metal oxide: highly active visible light photocatalysts with improved chemical stability.

    Science.gov (United States)

    Gunjakar, Jayavant L; Kim, Tae Woo; Kim, Hyo Na; Kim, In Young; Hwang, Seong-Ju

    2011-09-28

    Mesoporous layer-by-layer ordered nanohybrids highly active for visible light-induced O(2) generation are synthesized by self-assembly between oppositely charged 2D nanosheets of Zn-Cr-layered double hydroxide (Zn-Cr-LDH) and layered titanium oxide. The layer-by-layer ordering of two kinds of 2D nanosheets is evidenced by powder X-ray diffraction and cross-sectional high resolution-transmission electron microscopy. Upon the interstratification process, the original in-plane atomic arrangements and electronic structures of the component nanosheets remain intact. The obtained heterolayered nanohybrids show a strong absorption of visible light and a remarkably depressed photoluminescence signal, indicating an effective electronic coupling between the two component nanosheets. The self-assembly between 2D inorganic nanosheets leads to the formation of highly porous stacking structure, whose porosity is controllable by changing the ratio of layered titanate/Zn-Cr-LDH. The resultant heterolayered nanohybrids are fairly active for visible light-induced O(2) generation with a rate of ∼1.18 mmol h(-1) g(-1), which is higher than the O(2) production rate (∼0.67 mmol h(-1) g(-1)) by the pristine Zn-Cr-LDH material, that is, one of the most effective visible light photocatalysts for O(2) production, under the same experimental condition. This result highlights an excellent functionality of the Zn-Cr-LDH-layered titanate nanohybrids as efficient visible light active photocatalysts. Of prime interest is that the chemical stability of the Zn-Cr-LDH is significantly improved upon the hybridization, a result of the protection of the LDH lattice by highly stable titanate layer. The present findings clearly demonstrate that the layer-by-layer-ordered assembly between inorganic 2D nanosheets is quite effective not only in improving the photocatalytic activity of the component semiconductors but also in synthesizing novel porous LDH-based hybrid materials with improved chemical

  4. Industrial wastes as low-cost potential adsorbents for the treatment of wastewater laden with heavy metals.

    Science.gov (United States)

    Ahmaruzzaman, M

    2011-08-10

    Industrial wastes, such as, fly ash, blast furnace slag and sludge, black liquor lignin, red mud, and waste slurry, etc. are currently being investigated as potential adsorbents for the removal of the heavy metals from wastewater. It was found that modified industrial wastes showed higher adsorption capacity. The application of low-cost adsorbents obtained from the industrial wastes as a replacement for costly conventional methods of removing heavy metal ions from wastewater has been reviewed. The adsorption mechanism, influencing factors, favorable conditions, and competitive ions etc. on the adsorption of heavy metals have also been discussed in this article. From the review, it is evident that certain industrial waste materials have demonstrated high removal capacities for the heavy metals laden with wastewater. However, it is to be mentioned that adsorption capacities of the adsorbents vary depending on the characteristics of the adsorbents, the extent of chemical modification and the concentration of adsorbates. There are also few issues and drawbacks on the utilization of industrial wastes as low-cost adsorbents that have been addressed. In order to find out the practical utilization of industrial waste as low-cost adsorbents on the commercial scale, more research should be conducted in this direction. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Textural and chemical characterizations of adsorbent prepared from palm shell by potassium hydroxide impregnation at different stages.

    Science.gov (United States)

    Guo, Jia; Lua, Aik Chong

    2002-10-15

    Preparation and characterization of activated carbon from palm shell, a carbonaceous agricultural solid waste, by potassium hydroxide treatment at different stages were studied. The effects of activation temperature and chemical to sample ratio on the characteristics of the activated carbon were investigated. Fixed-bed adsorption of sulfur dioxide (SO(2)) gas was carried out to evaluate the adsorptive capacity of the samples. Desorption tests were conducted to verify the occurrence of chemisorption due to some surface functional groups or of chemical reaction between SO(2) and KOH. It was found that pre-impregnation of raw palm shell was involved in replacement of some hydrogen ions with potassium ions to form cross-linked complexes, which retarded the tar formation during carbonization, resulting in a relatively high yield. Moreover, these potassium ions accelerated the reaction as catalysts during gasification of chars by carbon dioxide. For chars with mid-impregnation, potassium hydroxide acted in two ways: (i) formation of metallic potassium by dehydration and (ii) conversion into potassium carbonate. Metallic potassium intercalated to the carbon matrix accounted for pore development and potassium carbonate layer prevented the sample from over burn-off. Post-impregnation of final products modified the textural characteristics of the sample as some pore entrances were blocked by chemicals. However, potassium hydroxide enhanced the amount of SO(2) uptaken via formation of potassium sulfite.

  6. Screening of heavy metal containing waste types for use as raw material in Arctic clay-based bricks

    DEFF Research Database (Denmark)

    Belmonte, Louise Josefine; Ottosen, Lisbeth M.; Kirkelund, Gunvor Marie

    2016-01-01

    In the vulnerable Arctic environment, the impact of especially hazardous wastes can have severe consequences and the reduction and safe handling of these waste types are therefore an important issue. In this study, two groups of heavy metal containing particulate waste materials, municipal solid...... waste incineration (MSWI) fly and bottom ashes and mine tailings (i.e., residues from the mineral resource industry) from Greenland were screened in order to determine their suitability as secondary resources in clay-based brick production. Small clay discs, containing 20 or 40% of the different...... particulate waste materials, were fired and material properties and heavy metal leaching tests were conducted before and after firing. Remediation techniques (washing in distilled water and electrodialytical treatment) applied to the fly ash reduced leaching before firing. The mine tailings and bottom ash...

  7. Directions of development of research methods in the assessment of leaching of heavy metals from mineral waste

    Directory of Open Access Journals (Sweden)

    Król Anna

    2016-01-01

    Full Text Available There are many test methods to assess the level of the release of heavy metals into the environment from mineral waste materials. Leaching methods can be different depending on the leaching time periods, leaching dynamics, sample preparation method or the pH of the elution medium. In Poland, little attention is paid to the research on the relationship between the leaching of particular heavy metals from mineral wastes and changes in environmental conditions, including the pH of the environment. Tests being carried out abroad have started to pay great attention to the pH-dependent impact of the environment and the liquid being in contact with the material on the degree of leaching contaminants from wastes. The solubility of all metals depends on the value of the pH. Authors of the paper will try to prove that Polish methods of waste characterization is incomplete and inconsistent with opinions prevailing in the global literature. The procedure described in the Polish standards are insufficient to determine the actual level of leaching of heavy metals having regard to the impact of multiple external conditions on the level of leaching of heavy metals. Paper will present a directions of development of research methods in the assessment of leaching of heavy metals from mineral waste.

  8. Development of waste packages for TRU-disposal. 5. Development of cylindrical metal package for TRU wastes

    International Nuclear Information System (INIS)

    Mine, Tatsuya; Mizubayashi, Hiroshi; Asano, Hidekazu; Owada, Hitoshi; Otsuki, Akiyoshi

    2005-01-01

    Development of the TRU waste package for hulls and endpieces compression canisters, which include long-lived and low sorption nuclides like C-14 is essential and will contribute a lot to a reasonable enhancement of safety and economy of the TRU-disposal system. The cylindrical metal package made of carbon steel for canisters to enhance the efficiency of the TRU-disposal system and to economically improve their stacking conditions was developed. The package is a welded cylindrical construction with a deep drawn upper cover and a disc plate for a bottom cover. Since the welding is mainly made only for an upper cover and a bottom disc plate, this package has a better containment performance for radioactive nuclide and can reduce the cost for construction and manufacturing including its welding control. Furthermore, this package can be laid down in pile for stacking in the circular cross section disposal tunnel for the sedimentary rock, which can drastically minimize the space for disposal tunnel as mentioned previously in TRU report. This paper reports the results of the study for application of newly developed metal package into the previous TRU-disposal system and for the stacking equipment for the package. (author)

  9. Comparison of soil heavy metal pollution caused by e-waste recycling activities and traditional industrial operations.

    Science.gov (United States)

    He, Kailing; Sun, Zehang; Hu, Yuanan; Zeng, Xiangying; Yu, Zhiqiang; Cheng, Hefa

    2017-04-01

    The traditional industrial operations are well recognized as an important source of heavy metal pollution, while that caused by the e-waste recycling activities, which have sprouted in some developing countries, is often overlooked. This study was carried out to compare the status of soil heavy metal pollution caused by the traditional industrial operations and the e-waste recycling activities in the Pearl River Delta, and assess whether greater attention should be paid to control the pollution arising from e-waste recycling activities. Both the total contents and the chemical fractionation of major heavy metals (As, Cr, Cd, Ni, Pb, Cu, and Zn) in 50 surface soil samples collected from the e-waste recycling areas and 20 soil samples from the traditional industrial zones were determined. The results show that the soils in the e-waste recycling areas were mainly polluted by Cu, Zn, As, and Cd, while Cu, Zn, As, Cd, and Pb were the major heavy metals in the soils from the traditional industrial zones. Statistical analyses consistently show that Cu, Cd, Pb, and Zn in the surface soils from both types of sites were contributed mostly by human activities, while As, Cr, and Ni in the soils were dominated by natural background. No clear distinction was found on the pollution characteristic of heavy metals in the surface soils between the e-waste recycling areas and traditional industrial zones. The potential ecological risk posed by heavy metals in the surface soils from both types of sites, which was dominated by that from Cd, ranged from low to moderate. Given the much shorter development history of e-waste recycling and its largely unregulated nature, significant efforts should be made to crack down on illegal e-waste recycling and strengthen pollution control for related activities.

  10. Scoping evaluation of the technical capabilities of DOE sites for disposal of hazardous metals in mixed low-level waste

    International Nuclear Information System (INIS)

    Gruebel, M.M.; Waters, R.D.; Langkopf, B.S.

    1997-05-01

    A team of analysts designed and conducted a scoping evaluation to estimate the technical capabilities of fifteen Department of Energy sites for disposal of the hazardous metals in mixed low-level waste (i.e., waste that contains both low-level radioactive materials and hazardous constituents). Eight hazardous metals were evaluated: arsenic, barium, cadmium, chromium, lead, mercury, selenium, and silver. The analysis considered transport only through the groundwater pathway. The results are reported as site-specific estimates of maximum concentrations of each hazardous metal in treated mixed low-level waste that do not exceed the performance measures established for the analysis. Also reported are site-specific estimates of travel times of each hazardous metal to the point of compliance

  11. Heavy Metals in Soils and Vegetables Irrigated with Urban Grey Waste Water in Fagge, Kano, Nigeria.

    Science.gov (United States)

    Chiroma, T M; Ebewele, R O; Hymore, F K

    2014-01-01

    There is currently an increased consumption of vegetables within the local urban community. However, contamination of these vegetables with heavy metals poses a potential health hazard. Consequently, the potential contamination problem due to the effect of levels of some heavy metals (Fe, Mg, Zn, Mn, Cu and Cr) in soils and vegetables irrigated with drainage urban grey waste water were investigated. The maximum levels of Fe, Zn, Mn, Cu and Cr in the urban grey waste waters were respectively 2.8, 2.1, 19.5, 2.3 and 143.1 times, higher than the maximum recommended concentrations of these metals: 5.0 μg/mL, 2.0 μg/mL, 0.2 μg/mL, 0.2 μg/mL and 0.1 μg/mL, respectively, for irrigation waters. The soils were found to be contaminated with these metals to levels that range between 24 to 84 percent contaminations. Although the heavy metals concentration ranking in vegetable parts vary with plant specie, the concentrations of Fe, Zn, Mn, Cu and Cr in most parts of the vegetables were above their critical concentrations of 750 - 1000 μg/g, 100 - 400 μg/g, 300 - 500 μg/g, 20 - 100 μg/g and 5 - 30 μg/g, respectively, in plants. This suggests potential toxicity of these parts of vegetables. It was however found that over 40 percent of the concentrations of Fe, Mg, Zn and Cu in Onions, Fe in Okro, Cr in Bushgreen, Cu in Roselle and Zn, Cu in Carrot leaves can be easily removed by washing the leaves with water. However, only Cu concentration in Onions and Bushgreen leaves met the acceptable permissible level in plants after washing.

  12. Chemicals, metals, and pesticide pits waste unit low induction number electromagnetic survey

    Energy Technology Data Exchange (ETDEWEB)

    Cumbest, R.J.; Mohon, D.

    1995-06-01

    An electromagnetic survey was conducted at the Chemicals, Metals, and Pesticide Waste Unit to identify any buried metallic objects that may be present in the materials used to fill and cover the pits after removal of pit debris. The survey was conducted with a Geonics EM-31 Terrain Conductivity Meter along north - south oriented traverses with 5-ft station intervals to produce a 5-ft by 5-ft square grid node pattern. Both conductivity and in-phase components were measured at each station for vertical dipole orientation with the common axis of the dipoles in the north - south and east - west orientations. The conductivity data clearly show elevated conductivities (2.1 to 7.0 mS/m) associated with the material over the pits, as compared with the surrounding area that is characterized by lower conductivities (1 to 2 mS/m). This is probably the result of the higher clay content of the fill material relative to the surrounding area, which has a higher sand to clay ratio and the presence of a plastic cover beneath the fill that has probably trapped water. Many metal objects are present in the survey area including manhole covers, monitoring well heads, metal, signs, drain culverts, abandoned wells, and BP waste unit marker balls. AU of these exhibit associated conductivity and in-phase anomalies of various magnitude. In addition to these anomalies that can be definitely associated with surface sources, conductivity and in-phase anomalies are also present with no obvious surface source. These anomalies are probably indicative of subsurface buried metallic objects. A high concentration of these objects appears to be present in the southwest corner of the survey area.

  13. Eco-toxicity and metal contamination of paddy soil in an e-wastes recycling area

    International Nuclear Information System (INIS)

    Zhang Junhui; Hang Min

    2009-01-01

    Paddy soil samples taken from different sites in an old primitive electronic-waste (e-waste) processing region were examined for eco-toxicity and metal contamination. Using the environmental quality standard for soils (China, Grade II) as reference, soil samples of two sites were weakly contaminated with trace metal, but site G was heavily contaminated with Cd (6.37 mg kg -1 ), and weakly contaminated with Cu (256.36 mg kg -1 ) and Zn (209.85 mg kg -1 ). Zn appeared to be strongly bound in the residual fraction (72.24-77.86%), no matter the soil was metal contaminated or not. However, more than 9% Cd and 16% Cu was present in the non-residual fraction in the metal contaminated soils than in the uncontaminated soil, especially for site G and site F. Compared with that of the control soil, the micronucleus rates of site G and site F soil treatments increased by 2.7-fold and 1.7-fold, respectively. Low germination rates were observed in site C (50%) and site G (50%) soil extraction treated rice seeds. The shortest root length (0.2377 cm) was observed in site G soil treated groups, which is only 37.57% of that of the control soil treated groups. All of the micronucleus ratio of Vicia faba root cells, rice germination rate and root length after treatment of soil extraction indicate the eco-toxicity in site F and G soils although the three indexes are different in sensitivity to soil metal contamination.

  14. Function of all-metal separators for waste fuels. Phase 1; Funktion av allmetallseparatorer foer avfallsbraenslen. Etapp 1

    Energy Technology Data Exchange (ETDEWEB)

    Jacoby, Juergen; Wrangensten, Lars

    2004-08-01

    Various waste incineration facilities, which use different types of waste fuels, have difficulties with a high content of non-magnetic metal, especially aluminum in their fuels. Aluminum may melt on the grate and can lead to corrosion or fouling in the furnace. Additionally, a high content of aluminum in the flyash may cause difficulties in terms of storage or further use of the ash as e.g. construction material. The industrial demand for efficient separators for non-magnetic metals from a fuel stream is rather large. There is however some uncertainty in the performance and efficiency of metal separators. Two types of separators can be found, the first type is called eddy current separator, the other type is based upon a metal detector with a sorting unit in the form of a chute or similar afterwards. An eddy current separator consists of a fast rotating drum containing several permanent magnets with alternating polarity. Due to the rotation, the change in the magnetic field induces eddy currents in conducting materials. The eddy currents cause a force in non-magnetic metal, the Lorentz force, which repels the material away from the rotating drum while all other material follows the systems flow direction. Systems equipped with a metal detector activate a mechanical sorting device, separate chute or air nozzles, when a metal particle is detected. In contrast to eddy current separators all types of metals can be detected and sorted out by systems based on metal detector. Several technical solutions for metal separation supplied by various manufacturers are described in the report. The companies have been asked to supply product information on the working principle, technical data, efficiency and limits for different types of metals. Two reference power plants have been visited and their experiences with all-metal separators are described. Haendeloeverket in Norrkoeping uses eddy current separators for separation of non-magnetic metals from household waste

  15. Evaluation of heavy metal leaching from spent household batteries disposed in municipal solid waste.

    Science.gov (United States)

    Karnchanawong, Somjai; Limpiteeprakan, Pawena

    2009-02-01

    Batch leaching tests and simulated landfill lysimeter tests were performed to evaluate the contents of heavy metals leached from spent batteries in the municipal solid waste. The toxicity characteristic leaching procedure was utilized to perform the batch leaching tests of 36 spent batteries. Four lysimeters were prepared with battery contents ranging from 0% to 100% by weight for column tests, and the experiments were performed at ambient temperature. The age of all the batteries used in the study ranged from freshly disposed up to approximately 3 years old. The results from the batch tests showed that the type of battery influenced the heavy metal concentrations in the leached solutions. The lysimeter experiment results illustrated that at lower pH levels more metals are leached than at higher pH levels. The increasing amount of batteries disposed in landfills can contribute to the leaching of more metals, especially Mn and Zn, into the environment. These results indicate that the direct disposal of spent household batteries into a MSW landfill can increase the heavy metal contents in the landfill leachate.

  16. Behavior of metals in ash melting and gasification-melting of municipal solid waste (MSW).

    Science.gov (United States)

    Jung, C H; Matsuto, T; Tanaka, N

    2005-01-01

    In this study, metal behavior in ash-melting and municipal solid waste (MSW) gasification-melting facilities were investigated. Eight ash-melting and three MSW gasification-melting facilities with a variety of melting processes and feedstocks were selected. From each facility, melting furnace fly ash (MFA) and molten slag were sampled, and feedstock of the ash-melting processes was also taken. For the ash melting process, the generation rate of MFA was well correlated with the ratio of incineration fly ash (IFA) in feedstock, and this was because MFA was formed mostly by mass transfer from IFA and a limited amount from bottom ash (BA). Distribution ratios of metal elements to MFA were generally determined by volatility of the metal element, but chlorine content in feedstock had a significant effect on Cu and a marginal effect on Pb. Distribution ratio of Zn to MFA was influenced by the oxidizing atmosphere in the furnace. High MFA generation and distribution ratio of non-volatile metals to MFA in gasification-melting facilities was probably caused by carry-over of fine particles to the air pollution control system due to large gas volume. Finally, dilution effect was shown to have a significant effect on metal concentration in MFA.

  17. Uranium and other heavy metal resistance and accumulation in bacteria isolated from uranium mine wastes.

    Science.gov (United States)

    Choudhary, Sangeeta; Islam, Ekramul; Kazy, Sufia K; Sar, Pinaki

    2012-01-01

    Ten bacterial strains isolated from uranium mine wastes were characterized in terms of their uranium and other metal resistance and accumulation. 16S rRNA gene sequence analysis identified the strains as members of genera Bacillus, Serratia, and Arthrobacter. Strains were able to utilize various carbon sources, particularly aromatic hydrocarbons, grow at broad pH and temperature ranges and produce non specific acid phosphatase relevant for metal phosphate precipitation in contaminated environment. The isolates exhibited high uranium and other heavy metals (Ni, Co, Cu and Cd) resistance and accumulation capacities. Particularly, Arthrobacter sp. J001 and Bacillus sp. J003 were superior in terms of U resistance at low pH (pH 4.0) along with metals and actinides (U and Th) removal with maximum cell loading of 1088 μmol U, 1293 μmol Th, 425 μmol Cu, 305 μmol Cd, 377 μmol Zn, 250 μmol Ni g(-1) cell dry wt. Genes encoding P(1B)-type ATPases (Cu-CPx and Zn-CPx) and ABC transporters (nik) as catalytic tools for maintaining cellular metal homeostasis were detected within several Bacillus spp., with possible incidence of horizontal gene transfer for the later gene showing phylogenetic lineage to α Proteobacteria members. The study provides evidence on intrinsic abilities of indigenous bacteria from U-mine suitable for survival and cleaning up of contaminated mine sites.

  18. Equilibrium and kinetics studies of heavy metal ions biosorption on green algae waste biomass.

    Science.gov (United States)

    Bulgariu, Dumitru; Bulgariu, Laura

    2012-01-01

    The biosorption of Pb(II), Cd(II), and Co(II), respectively, from aqueous solution on green algae waste biomass was investigated. The green algae waste biomass was obtained from marine green algae after extraction of oil, and was used as low-cost biosorbent. Batch shaking experiments were performed to examine the effects of initial solution pH, contact time and temperature. The equilibrium biosorption data were analyzed using two isotherm models (Langmuir and Freundlich) and two kinetics models (pseudo-first order and pseudo-second order). The results indicate that Langmuir model provide best correlation of experimental data, and the pseudo-second order kinetic equation could best describe the biosorption kinetics of considered heavy metals. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Membranes prepared by radiation grafting of binary monomers for adsorption of heavy metals from industrial wastes

    Science.gov (United States)

    Hegazy, El-Sayed A.; Kamal, H.; Maziad, N.; Dessouki, A. M.

    1999-05-01

    Preparation of synthetic membranes using simultaneous radiation grafting of acrylic acid (AAc) and styrene (Sty) as individually and in binary monomer mixture onto low density polyethylene (LDPE) has been carried out. The effect of preparation conditions such as irradiation dose, monomer concentration, comonomer composition, and solvent on the grafting yield was investigated. Characterization and some properties of the prepared membranes using different analytical techniques are studied, accordingly the possibility of its practical use in industrial waste treatment is determined. The swelling behavior, electrical conductivity, thermal stability, and mechanical properties of the membranes were investigated as a function of the grafting degree. The prepared cation-exchange membranes possessed good electrical and mechanical properties, high thermal stability and possess good characteristics for separation processes. These membranes have also good affinity toward the adsorption or chelation with Fe 3+ and Pb 2+ ions either in mixture containing other metals or if exists alone in the waste solution.

  20. Magnetic Adsorption Method for the Treatment of Metal Contaminated Aqueous Waste

    International Nuclear Information System (INIS)

    Cotten, G.B.; Eldredge, H.B.; Navratil, J.D.

    1999-01-01

    There have been many recent developments in separation methods used for treating radioactive and non-radioactive metal bearing liquid wastes. These methods have included adsorption, ion exchange, solvent extraction and other chemical and physical techniques. To date very few, if any, of these processes can provide a low cost and environmentally benign solution. Recent research into the use of magnetite for wastewater treatment indicates the potential for magnetite both cost and environment drivers. A brief review of recent work in using magnetite as a sorbent is presented as well as recent work performed in our laboratory using supported magnetite in the presence of an external magnetic field. The application to groundwater and other aqueous waste streams is discussed. Recent research has focused on supporting magnetite in an economical (as compared to the magnetic polymine-epichlorohydrine resin) and inert (non-reactive, chemically or otherwise) environment that promotes both adsorption and satisfactory flow characteristics

  1. Determination of Different Metals in Steel Waste Samples Using laser Induced Breakdown Spectroscopy

    Directory of Open Access Journals (Sweden)

    A. H. Bakry

    2007-12-01

    Full Text Available Elemental analysis of waste samples collected from steel products manufacturing plant (SPS located at industrial city of Jeddah, Saudi-Arabia has been carried out using Laser Induced Breakdown Spectroscopy (LIBS. The 1064 nm laser radiations from a Nd:YAG laser at an irradiance of 7.6  1010 W cm –2 were used. Atomic emission spectra of the elements present in the waste samples were recorded in the 200 – 620 nm region. Elements such as Fe, W, Ti, Al, Mg, Ca, S, Mn, and Na were detected in these samples. Quantitative determination of the elemental concentration was obtained for these metals against certified standard samples. Parametric dependences of LIBS signal intensity on incident laser energy and time delay between the laser pulse and data acquisition system were also carried out.

  2. Wear Behavior of Aluminium Metal Matrix Composite Prepared from Industrial Waste.

    Science.gov (United States)

    Xavier, L Francis; Suresh, Paramasivam

    2016-01-01

    With an increase in the population and industrialization, a lot of valuable natural resources are depleted to prepare and manufacture products. However industrialization on the other hand has waste disposal issues, causing dust and environmental pollution. In this work, Aluminium Metal Matrix Composite is prepared by reinforcing 10 wt% and 20 wt% of wet grinder stone dust particles an industrial waste obtained during processing of quarry rocks which are available in nature. In the composite materials design wear is a very important criterion requiring consideration which ensures the materials reliability in applications where they come in contact with the environment and other surfaces. Dry sliding wear test was carried out using pin-on-disc apparatus on the prepared composites. The results reveal that increasing the reinforcement content from 10 wt% to 20 wt% increases the resistance to wear rate.

  3. Isolation of Metals from Liquid Wastes: Reactive Scavenging in Turbulent Thermal Reactors

    International Nuclear Information System (INIS)

    Jost O.L. Wendt; Alan R. Kerstein; Alexander Scheeline; Arne Pearlstein; William Linak

    2003-01-01

    The Overall project demonstrated that toxic metals (cesium Cs and strontium Sr) in aqueous and organic wastes can be isolated from the environment through reaction with kaolinite based sorbent substrates in high temperature reactor environments. In addition, a state-of-the art laser diagnostic tool to measure droplet characteristic in practical 'dirty' laboratory environments was developed, and was featured on the cover of a recent edition of the scientific journal ''applied Spectroscopy''. Furthermore, great strides have been made in developing a theoretical model that has the potential to allow prediction of the position and life history of every particle of waste in a high temperature, turbulent flow field, a very challenging problem involving as it does, the fundamentals of two phase turbulence and of particle drag physics

  4. Wear Behavior of Aluminium Metal Matrix Composite Prepared from Industrial Waste

    Directory of Open Access Journals (Sweden)

    L. Francis Xavier

    2016-01-01

    Full Text Available With an increase in the population and industrialization, a lot of valuable natural resources are depleted to prepare and manufacture products. However industrialization on the other hand has waste disposal issues, causing dust and environmental pollution. In this work, Aluminium Metal Matrix Composite is prepared by reinforcing 10 wt% and 20 wt% of wet grinder stone dust particles an industrial waste obtained during processing of quarry rocks which are available in nature. In the composite materials design wear is a very important criterion requiring consideration which ensures the materials reliability in applications where they come in contact with the environment and other surfaces. Dry sliding wear test was carried out using pin-on-disc apparatus on the prepared composites. The results reveal that increasing the reinforcement content from 10 wt% to 20 wt% increases the resistance to wear rate.

  5. Magnetic Adsorption Method for the Treatment of Metal Contaminated Aqueous Waste

    Energy Technology Data Exchange (ETDEWEB)

    G. B. Cotten (Parsons); J. D. Navratil (INEEL); H. B. Eldredge (U of Idaho)

    1999-03-01

    There have been many recent developments in separation methods used for treating radioactive and non-radioactive metal bearing liquid wastes. These methods have included adsorption, ion exchange, solvent extraction and other chemical and physical techniques. To date very few, if any, of these processes can provide a low cost and environmentally benign solution. Recent research into the use of magnetite for wastewater treatment indicates the potential for magnetite both cost and environment drivers. A brief review of recent work in using magnetite as a sorbent is presented as well as recent work performed in our laboratory using supported magnetite in the presence of an external magnetic field. The application to groundwater and other aqueous waste streams is discussed. Recent research has focused on supporting magnetite in an economical (as compared to the magnetic polymine-epichlorohydrine resin) and inert (non-reactive, chemically or otherwise) environment that promotes both adsorption and satisfactory flow characteristics.

  6. Isolation of Metals from Liquid Wastes: Reactive Scavenging in Turbulent Thermal Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Jost O.L. Wendt; Alan R. Kerstein; Alexander Scheeline; Arne Pearlstein; William Linak

    2003-08-06

    The Overall project demonstrated that toxic metals (cesium Cs and strontium Sr) in aqueous and organic wastes can be isolated from the environment through reaction with kaolinite based sorbent substrates in high temperature reactor environments. In addition, a state-of-the art laser diagnostic tool to measure droplet characteristic in practical 'dirty' laboratory environments was developed, and was featured on the cover of a recent edition of the scientific journal ''applied Spectroscopy''. Furthermore, great strides have been made in developing a theoretical model that has the potential to allow prediction of the position and life history of every particle of waste in a high temperature, turbulent flow field, a very challenging problem involving as it does, the fundamentals of two phase turbulence and of particle drag physics.

  7. Recovery of metals from waste printed circuit boards by supercritical water pre-treatment combined with acid leaching process.

    Science.gov (United States)

    Xiu, Fu-Rong; Qi, Yingying; Zhang, Fu-Shen

    2013-05-01

    Waste printed circuit boards (PCBs) contain a large number of metals such as Cu, Sn, Pb, Cd, Cr, Zn, and Mn. In this work, an efficient and environmentally friendly process for metals recovery from waste PCBs by supercritical water (SCW) pre-treatment combined with acid leaching was developed. In the proposed process, waste PCBs were pre-treated by SCW, then the separated solid phase product with concentrated metals was subjected to an acid leaching process for metals recovery. The effect of SCW pre-treatment on the recovery of different metals from waste PCBs was investigated. Two methods of SCW pre-treatment were studied: supercritical water oxidation (SCWO) and supercritical water depolymerization (SCWD). Experimental results indicated that SCWO and SCWD pre-treatment had significant effect on the recovery of different metals. SCWO pre-treatment was highly efficient for enhancing the recovery of Cu and Pb, and the recovery efficiency increased significantly with increasing pre-treatment temperature. The recovery efficiency of Cu and Pb for SCWO pre-treatment at 420°C was 99.8% and 80%, respectively, whereas most of the Sn and Cr were immobilized in the residue. The recovery of all studied metals was enhanced by SCWD pre-treatment and increased along with pre-treatment temperature. Up to 90% of Sn, Zn, Cr, Cd, and Mn could be recovered for SCWD pre-treatment at 440°C. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Recovering metals from sewage sludge, waste incineration residues and similar substances with hyperaccumulative plants

    Science.gov (United States)

    Kisser, Johannes; Gattringer, Heinz; Iordanopoulos-Kisser, Monika

    2015-04-01

    Sewage sludges as well as ashes from waste incineration plants are known accumulation sinks of many elements that are either important nutrients for biological organisms (phosphorus, potassium, magnesium, etc.) or valuable metals when considered on their own in pure form (nickel, chrome, zinc, etc.); they are also serious pollutants when they occur in wild mixtures at localized anthropogenic end- of-stream points. Austria and many other countries have to import up to 90% of the material inputs of metals from abroad. These primary resources are becoming more expensive as they become more scarce and remaining deposits more difficult to mine, which is a serious concern for industrialized nations. Basic economic and strategic reasoning demands an increase in recycling activities and waste minimization. Technologies to recover metals in a reasonable and economically relevant manner from very diffuse sources are practically non-existent or require large amounts of energy and chemicals, which pose environmental risks. On the other hand agriculture uses large volumes of mineral fertilizers, which are often sourced from mines as well, and thus are also subject to the same principle of finiteness and potential shortage in supply. These converted biological nutrients are taken up by crops and through the food chain and human consumption end up in sewage systems and in wastewater treatment plants in great quantities. The metabolized nutrients mostly do not return to agriculture, but due to contamination with heavy metals are diverted to be used as construction aggregates or are thermally treated and end up rather uselessly in landfills. The project BIO-ORE aimed to explore new pathways to concentrate metals from diluted sources such as sewage sludge and wastewater by using highly efficient biological absorption and transport mechanisms. These enzymatic systems from plants work with very little energy input. The process is called bioaccumulation and can be most effectively

  9. Synthesis, structure refinement and chromate sorption characteristics of an Al-rich bayerite-based layered double hydroxide

    Energy Technology Data Exchange (ETDEWEB)

    Britto, Sylvia, E-mail: sylviabritto11@gmail.com; Kamath, P. Vishnu

    2014-07-01

    “Imbibition” of Zn{sup 2+} ions into the cation vacancies of bayerite–Al(OH){sub 3} and NO{sub 3}{sup −} ions into the interlayer gallery yields an Al-rich layered double hydroxide with Al/Zn ratio ∼3. NO{sub 3}{sup −} ions are intercalated with their molecular planes inclined at an angle to the plane of the metal hydroxide slab and bonded to it by hydrogen bonds. Rietveld refinement of the structure shows that the monoclinic symmetry of the precursor bayerite is preserved in the product, showing that the imbibition is topochemical in nature. The nitrate ion is labile and is quantitatively replaced by CrO{sub 4}{sup 2−} ions from solution. The uptake of CrO{sub 4}{sup 2−} ions follows a Langmuir adsorption isotherm, thus showing that the hydroxide is a candidate material for green chemistry applications for the removal of CrO{sub 4}{sup 2−} ions from waste water. Rietveld refinement of the structure of the hydroxide after CrO{sub 4}{sup 2−} inclusion reveals that the CrO{sub 4}{sup 2−} ion is intercalated with one of its 2-fold axes parallel to the b-crystallographic axis of the crystal, also the principal 2 axis of the monoclinic cell. - Graphical abstract: The structure of the [Zn–Al4-nitrate] LDH viewed along the a-axis. - Highlights: • Synthesis of Al-rich layered double hydroxide with Al/Zn ratio ∼3. • Rietveld refinement indicates that the imbibition of Zn into Al(OH){sub 3} is topochemical in nature. • The uptake of CrO{sub 4}{sup 2−} ions follows a Langmuir adsorption isotherm.

  10. Selective extraction and recovery of rare earth metals from phosphor powders in waste fluorescent lamps using an ionic liquid system

    International Nuclear Information System (INIS)

    Yang, Fan; Kubota, Fukiko; Baba, Yuzo; Kamiya, Noriho; Goto, Masahiro

    2013-01-01

    Highlights: • Recycling of rare earth metals from fluorescent lamps was conducted by ionic liquid-mediated extraction. • Acid leaching from a waste phosphor powder was carried out using sulfuric and nitric acids. • An ionic liquid was used as extracting solvent for the rare earth metals. • Selective extraction of rare earth metals from leach solutions was attained. •The extracting ionic liquid phase was recyclable in the recovery process. -- Abstract: The recycling of rare earth metals from phosphor powders in waste fluorescent lamps by solvent extraction using ionic liquids was studied. Acid leaching of rare earth metals from the waste phosphor powder was examined first. Yttrium (Y) and europium (Eu) dissolved readily in the acid solution; however, the leaching of other rare earth metals required substantial energy input. Ionization of target rare earth metals from the waste phosphor powders into the leach solution was critical for their successful recovery. As a high temperature was required for the complete leaching of all rare earth metals, ionic liquids, for which vapor pressure is negligible, were used as an alternative extracting phase to the conventional organic diluent. An extractant, N, N-dioctyldiglycol amic acid (DODGAA), which was recently developed, showed a high affinity for rare earth metal ions in liquid–liquid extraction although a conventional commercial phosphonic extractant did not. An effective recovery of the rare earth metals, Y, Eu, La and Ce, from the metal impurities, Fe, Al and Zn, was achieved from the acidic leach solution of phosphor powders using an ionic liquid containing DODGAA as novel extractant system

  11. Recycling of non-metallic fractions from waste printed circuit boards: A review

    International Nuclear Information System (INIS)

    Guo Jiuyong; Guo Jie; Xu Zhenming

    2009-01-01

    The major economic driving force for recycling of waste printed circuit boards (PCBs) is the value of the metallic fractions (MFs) of PCBs. The non-metallic fractions (NMFs), which take up almost 70 wt% of waste PCBs, were treated by combustion or land filling in the past. However, combustion of the NMFs will cause the formation of highly toxic polybrominated dibenzodioxins and dibenzofurans (PBDD/Fs) while land filling of the NMFs will lead to secondary pollution caused by heavy metals and brominated flame retardants (BFRs) leaching to the groundwater. Therefore, recycling of the NMFs from waste PCBs is drawing more and more attention from the public and the governments. Currently, how to recycle the NMFs environmental soundly has become a significant topic in recycling of waste PCBs. In order to fulfill the better resource utilization of the NMFs, the compositions and characteristics of the NMFs, methods and outcomes of recycling the NMFs from waste PCBs and analysis and treatment for the hazardous substances contained in the NMFs were reviewed in this paper. Thermosetting resin matrix composites, thermoplastic matrix composites, concrete and viscoelastic materials are main applications for physical recycling of the NMFs. Chemical recycling methods consisting of pyrolysis, gasification, supercritical fluids depolymerization and hydrogenolytic degradation can be used to convert the NMFs to chemical feedstocks and fuels. The toxicity characteristic leaching procedure (TCLP) and synthetic precipitation leaching procedure (SPLP) can be used to determine the toxicity characteristic (TC) of the NMFs and to evaluate the environmental safety of products made from the recycled NMFs. It is believed that physical recycling of the NMFs has been a promising recycling method. Much more work should be done to develop comprehensive and industrialized usage of the NMFs recycled by physical methods. Chemical recycling methods have the advantages in eliminating hazardous substances

  12. TREATMENT OF METAL-LADEN HAZARDOUS WASTES WITH ADVANCED CLEAN COAL TECHNOLOGY BY-PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    James T. Cobb, Jr.; Ronald D. Neufeld; Jana Agostini

    1999-06-01

    This sixteenth quarterly report describes work done during the sixteenth three-month period of the University of Pittsburgh's project on the ''Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.'' This report describes the activities of the project team during the reporting period. The principal work has focused upon new laboratory evaluation of samples from Phase 1, discussions with MAX Environmental Technologies, Inc., on the field work of Phase 2, giving a presentation, and making and responding to several outside contacts.

  13. TREATMENT OF METAL-LADEN HAZARDOUS WASTES WITH ADVANCED CLEAN COAL TECHNOLOGY BY-PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    James T. Cobb, Jr.; Ronald D. Neufeld; Jana Agostini

    1999-01-01

    This seventeenth quarterly report describes work done during the seventeenth three-month period of the University of Pittsburgh's project on the ''Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.'' This report describes the activities of the project team during the reporting period. The principal work has focused upon new laboratory evaluation of samples from Phase 1, discussions with MAX Environmental Technologies, Inc., on the field work of Phase 2, giving a presentation, submitting a manuscript and making and responding to one outside contact.

  14. TREATMENT OF METAL-LADEN HAZARDOUS WASTES WITH ADVANCED CLEAN COAL TECHNOLOGY BY-PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    James T. Cobb, Jr.; Ronald D. Neufeld; Jana Agostini

    1999-05-11

    This fifteenth quarterly report describes work done during the fifteenth three-month period of the University of Pittsburgh's project on the ''Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.'' This report describes the activities of the project team during the reporting period. The principal work has focused upon new laboratory evaluation of samples from Phase 1, discussions with MAX Environmental Technologies, Inc., on the field work of Phase 2, preparing and giving presentations, and making and responding to several outside contacts.

  15. Drop Dynamics and Speciation in Isolation of Metals from Liquid Wastes by Reactive Scavenging

    Energy Technology Data Exchange (ETDEWEB)

    Arne J. Pearlstein; Alexander Scheeline

    2002-08-30

    Computational and experimental studies of the motion and dynamics of liquid drops in gas flows were conducted with relevance to reactive scavenging of metals from atomized liquid waste. Navier-Stoke's computations of deformable drops revealed a range of conditions from which prolate drops are expected, and showed how frajectiones of deformable drops undergoing deceleration can be computed. Experimental work focused on development of emission fluorescence, and scattering diagnostics. The instrument developed was used to image drop shapes, soot, and nonaxisymmetric departures from steady flow in a 22kw combustor

  16. TREATMENT OF METAL-LADEN HAZARDOUS WASTES WITH ADVANCED CLEAN COAL TECHNOLOGY BY-PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    James T. Cobb, Jr.; Ronald D. Neufeld; Jana Agostini

    1999-05-10

    This fourteenth quarterly report describes work done during the fourteenth three-month period of the University of Pittsburgh's project on the ''Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.'' This report describes the activities of the project team during the reporting period. The principal work has focused upon new laboratory evaluation of samples from Phase 1, discussions with MAX Environmental Technologies, Inc., on the field work of Phase 2, preparing presentations, and making and responding to two outside contacts.

  17. Recent Developments in Microbiological Approaches for Securing Mine Wastes and for Recovering Metals from Mine Waters

    Directory of Open Access Journals (Sweden)

    D. Barrie Johnson

    2014-04-01

    Full Text Available Mining of metals and coals generates solid and liquid wastes that are potentially hazardous to the environment. Traditional methods to reduce the production of pollutants from mining and to treat impacted water courses are mostly physico-chemical in nature, though passive remediation of mine waters utilizes reactions that are catalysed by microorganisms. This paper reviews recent advances in biotechnologies that have been proposed both to secure reactive mine tailings and to remediate mine waters. Empirical management of tailings ponds to promote the growth of micro-algae that sustain populations of bacteria that essentially reverse the processes involved in the formation of acid mine drainage has been proposed. Elsewhere, targeted biomineralization has been demonstrated to produce solid products that allow metals present in mine waters to be recovered and recycled, rather than to be disposed of in landfill.

  18. Recovery of Cu and valuable metals from E-waste using thermal plasma treatment

    Science.gov (United States)

    Mitrasinovic, Aleksandar; Pershin, Larry; Wen, John Z.; Mostaghimi, Javad

    2011-08-01

    A thermal plasma treatment was employed for economical recovery of valuable metals from e-waste. Cu-clad plates that simulated circuit boards were fed at the bottom of the reactor and treated with a plasma jet at temperatures between 385 and 840°C. Organic components of the Cu-clad plates were decomposed and contributed to the increased temperature of the offgas. Due to the low temperatures at the base of the reactor, the analyzed samples did not show losses characteristic for the plasma processes such as evaporation or metal oxidation. After plasma treatment, Cu foils were separated from the fiber glass and other solid residues allowing a complete recovery. Solid residues of the plates at the bottom of the reactor were crunched into small particles, allowing easy recycling or use as construction material.

  19. Selective extraction and recovery of rare earth metals from phosphor powders in waste fluorescent lamps using an ionic liquid system.

    Science.gov (United States)

    Yang, Fan; Kubota, Fukiko; Baba, Yuzo; Kamiya, Noriho; Goto, Masahiro

    2013-06-15

    The recycling of rare earth metals from phosphor powders in waste fluorescent lamps by solvent extraction using ionic liquids was studied. Acid leaching of rare earth metals from the waste phosphor powder was examined first. Yttrium (Y) and europium (Eu) dissolved readily in the acid solution; however, the leaching of other rare earth metals required substantial energy input. Ionization of target rare earth metals from the waste phosphor powders into the leach solution was critical for their successful recovery. As a high temperature was required for the complete leaching of all rare earth metals, ionic liquids, for which vapor pressure is negligible, were used as an alternative extracting phase to the conventional organic diluent. An extractant, N, N-dioctyldiglycol amic acid (DODGAA), which was recently developed, showed a high affinity for rare earth metal ions in liquid-liquid extraction although a conventional commercial phosphonic extractant did not. An effective recovery of the rare earth metals, Y, Eu, La and Ce, from the metal impurities, Fe, Al and Zn, was achieved from the acidic leach solution of phosphor powders using an ionic liquid containing DODGAA as novel extractant system. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Pollutant emissions during pyrolysis and combustion of waste printed circuit boards, before and after metal removal

    Energy Technology Data Exchange (ETDEWEB)

    Ortuño, Nuria; Conesa, Juan A., E-mail: ja.conesa@ua.es; Moltó, Julia; Font, Rafael

    2014-11-15

    The constant increase in the production of electronic devices implies the need for an appropriate management of a growing number of waste electrical and electronic equipment. Thermal treatments represent an interesting alternative to recycle this kind of waste, but particular attention has to be paid to the potential emissions of toxic by-products. In this study, the emissions from thermal degradation of printed circuit boards (with and without metals) have been studied using a laboratory scale reactor, under oxidizing and inert atmosphere at 600 and 850 °C. Apart from carbon oxides, HBr was the main decomposition product, followed by high amounts of methane, ethylene, propylene, phenol and benzene. The maximum formation of PAHs was found in pyrolysis at 850 °C, naphthalene being the most abundant. High levels of 2-, 4-, 2,4-, 2,6- and 2,4,6-bromophenols were found, especially at 600 °C. Emissions of PCDD/Fs and dioxin-like PCBs were quite low and much lower than that of PBDD/Fs, due to the higher bromine content of the samples. Combustion at 600 °C was the run with the highest PBDD/F formation: the total content of eleven 2,3,7,8-substituted congeners (tetra- through heptaBDD/Fs) was 7240 and 3250 ng WHO{sub 2005}-TEQ/kg sample, corresponding to the sample with and without metals, respectively. - Highlights: • Thermal decomposition of printed circuit boards (with and without metals) is studied. • Important differences were found at the different experimental conditions. • Emission of brominated pollutants is much higher than that of chlorinated. • Metal enhances emission of halogenated compounds. • An increase in the temperature produces the destruction of pollutants.

  1. Biosorption of heavy metals in polluted water, using different waste fruit cortex

    Science.gov (United States)

    Kelly-Vargas, Kevin; Cerro-Lopez, Monica; Reyna-Tellez, Silvia; Bandala, Erick R.; Sanchez-Salas, Jose Luis

    The biosorption capacity of different cortex fruit wastes including banana (Musa paradisiaca), lemon (Citrus limonum) and orange (Citrus sinensis) peel were evaluated. In order to perform these experiments, grinded dried cortexes were used as package in 100 mm high, 10 mm i.d. columns. The grinded material was powdered in a mortar and passed through a screen in order to get two different particle sizes, 2 and 1 mm, for all powders. To estimate the biosorption capabilities of the tested materials, different heavy metals were passed through the columns and the elution filtrate reloaded different times to increase the retention of metals. The heavy metals used were prepared as synthetic samples at 10 mg/L of Pb(NO3)2, Cd(NO3)2, and Cu(NO3)2·6H2O using primary standards. In preliminary experiments using banana cortex, it was found that material with 1 mm of particle size showed higher retention capability (up to12%) than the material with 2 mm of particle size. Considering these results, 1 mm particle size material was used in further experiments with the other waste materials. It was found that for Pb and Cu removal, lemon and orange cortex showed better biosorption capability when compared with banana cortex (up to 15% less for Pb and 48% less for Cu). For Cd, banana cortex showed better biosorption capability 57% (67.2 mg/g of cortex) more than orange (28.8 mg/g of cortex), and 82% more than lemon (12 mg/g of cortex). Reload of the columns with the filtrate after passing through the column improved the removal capability of all the materials tested from 10% to 50% depending on the cortex and metal tested.

  2. Re-Processing of Mining Waste: An Alternative Way to Secure Metal Supplies of European Union

    Science.gov (United States)

    Guézennec, Anne-Gwénaelle; Bodénan, Françoise; Bertrand, Guillaume; Fuentes, Annabelle; Bellenfant, Gael; Lemière, Bruno; d'Hugues, Patrick; Cassard, Daniel; Save, Maurice

    In France, a recently started project handled by the French geological survey (BRGM) is aimed at identifying interesting old mining wastes deposits at the national level and assessing the metal recovery potential of these dumps. By crossing several databases and information from BRGM archives, 95 old mining sites with sizeable tailings dumps were identified. Selection criteria used to draw up this list were chosen mainly on the basis of the "Criticality Report" compiled for the European Commission in 2010, in which 14 mineral raw materials — 12 critical metals- have been explicitly named as highly critical for the industrial development of the European Union. In most of these mines which date back hundreds of years or more, only a single or at best a couple of metals were extracted with processes whose performances were considerably lower than those used today. Knowing the type of ore commodities and the processes characteristics, it has been thus possible to assess the presence of valuable elements for each tailings dump. From this list an Ag-Pb French abandoned mine has then been selected as a case study to evaluate the potential of extraction of metals still remaining in the tailings with special focus on Ag and Sb. A global site characterization methodology is proposed which can be extrapolated to other sites according to key parameters.

  3. Studies and determination of heavy metals in waste tyres and their impacts on the environment

    International Nuclear Information System (INIS)

    Shakya, P.R.; Shrestha, P.; Tamrakar, C.S.; Bhattarai, P.

    2006-01-01

    Uncontrolled burning of waste vehicle tyres causing environmental pollution has become a popular practice in developing countries like Nepal. Such activities were banned in many countries considering the environment and public health hazards but the official ban was ignored in many countries like Nepal. An experiment was conducted in a laboratory scale in an attempt to understand the potential discharge of trace metals content in Kathmandu Valley due to scrap tyre fires. For this purpose, four tyre types viz., CYCN, CSKR, BTIN and BBJP were collected representing the first two categories from passenger car and the last two from motorbike. An Atomic Absorption Spectrophotometer (AAS) was used for determination of metal concentration. Among the five heavy metals determined, Zn was detected in significantly high levels in all the tested tyre samples whereas Cd and Cr were found significantly less in many of them. The concentrations of Cd, Cr, Fe, Pb and Zn ranged from 0.020 - 27.1 micro g/g, 0.14 - 1.18 micro g/g, 17.8 - 381 micro g/g, 0.96 - 458 micro g/g and 3.95 - 8.21 micro g/g respectively. It was found that the metal concentration also varied with the tyre types and qualities. The potential discharge of the metals per representative scrap tyre mass was also estimated. Results indicate that the metal pollutants due to the uncontrolled burning of the scrap tyres could significantly contribute to deteriorate the environmental condition of the Valley. (author)

  4. Seasonal variations of coastal sedimentary trace metals cycling: insight on the effect of manganese and iron (oxy)hydroxides, sulphide and organic matter.

    Science.gov (United States)

    Dang, Duc Huy; Lenoble, Véronique; Durrieu, Gaël; Omanović, Dario; Mullot, Jean-Ulrich; Mounier, Stéphane; Garnier, Cédric

    2015-03-15

    The combination of analysis, multivariate treatment (PCA) and chemical speciation calculation confirmed the control of Fe, Mn, sulphide and organic matter on metals dynamics in coastal sediments (0-5 cm surface sediments and sediments cores) of Toulon Bay (NW Mediterranean). The temporal monitoring of the physic-chemical parameters as well as the dissolved/particulate minor (Fe/Mn) and trace elements (i.e. Ag, Cd, Co, Cu, Ni, Pb, Zn, …) concentrations in porewaters and sediments were assessed. Multivariate treatment revealed different behaviours for marine elements, terrestrial ones and contaminants. Seasonal variations of metals mobilization in porewater were observed, related to diagenesis activity. Element mobility was studied by selective extractions (ascorbate, acid and alkaline) on sediments. Thermodynamic simulation (PHREEQC) was performed to calculate the elemental dissolved speciation, the mineral saturation index and then to simulate the solid/liquid interaction through precipitation processes, studying the contrasted influence of dissolved organic matter and sulphide. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Migration of Hazardous Substances Through Soil. Part 2. Determination of the Leachability of Metals from Five Industrial Wastes and Their Movement within Soil

    Science.gov (United States)

    1985-08-01

    spent brines emerging from the electrolysis cells are treated, and the mercury is precipitated as the brine is concentrated and recycled. About 80 percent...block -- mb~er)Industrial wastes Chlorine production brine waste Electrplating wcste Toxic metals Nickel Cbt,’rpium battery waste Cadmium Inorganic...may be t1- oly mecil if concern and then only if the waste is co- disposed with municipai refuse. Chlorine production brine waste such as the sample

  6. Test plan for immobilization of salt-containing surrogate mixed wastes using polyester resins

    International Nuclear Information System (INIS)

    Biyani, R.K.; Douglas, J.C.; Hendrickson, D.W.

    1997-01-01

    Past operations at many Department of Energy (DOE) sites have resulted in the generation of several waste streams with high salt content. These wastes contain listed and characteristic hazardous constituents and are radioactive. The salts contained in the wastes are primarily chloride, sulfate, nitrate, metal oxides, and hydroxides. DOE has placed these types of wastes under the purview of the Mixed Waste Focus Area (MWFA). The MWFA has been tasked with developing and facilitating the implementation of technologies to treat these wastes in support of customer needs and requirements. The MWFA has developed a Technology Development Requirements Document (TDRD), which specifies performance requirements for technology owners and developers to use as a framework in developing effective waste treatment solutions. This project will demonstrate the use of polyester resins in encapsulating and solidifying DOE's mixed wastes containing salts, as an alternative to conventional and other emerging immobilization technologies

  7. A dipeptide-based superhydrogel: Removal of toxic dyes and heavy metal ions from waste water.

    Science.gov (United States)

    Nandi, Nibedita; Baral, Abhishek; Basu, Kingshuk; Roy, Subhasish; Banerjee, Arindam

    2017-01-01

    A short peptide-based molecule has been found to form a strong hydrogel at phosphate buffer solution of pH 7.46. The hydrogel has been characterized thoroughly using various techniques including field emission scanning electron microscopy (FE-SEM), wide angle powder X-ray diffraction (PXRD), and rheological analysis. It has been observed from FE-SEM images that entangled nanofiber network is responsible for gelation. Rheological investigation demonstrates that the self-assembly of this synthetic dipeptide results in the formation of mechanically strong hydrogel with storage modulus (G') around 10 4 Pa. This gel has been used for removing both cationic and anionic toxic organic dyes (Brilliant Blue, Congo red, Malachite Green, Rhodamine B) and metal ions (Co 2+ and Ni 2+ ) from waste water. Moreover, only a small amount of the gelator is required (less than 1 mg/mL) for preparation of this superhydrogel and even this hydrogel can be reused three times for dye/metal ion absorption. This signifies the importance of the hydrogel towards waste water management. © 2016 Wiley Periodicals, Inc.

  8. Development and testing of a method for coating metallic wastes by thermosetting resins

    International Nuclear Information System (INIS)

    Tassigny, C. de

    1985-01-01

    Decommissioning of nuclear installations produces large-sized metallic components difficult to be compacted or to be inserted in the usual containers. The purpose of this study was to develop a coating procedure for low and medium activity wastes, in order to: - fix the contamination of the waste by a first appropriate layer; - protect this layer from mechanical shocks by a second thick layer; - reduce the diffusion of radionuclides. The study has proven the feasibility of depositing epoxy resins by electrostatic spraying in a nuclear environment on steel sub-strata with an efficiency higher than 95%; showing that it is possible to work in closed ventilated rooms without risk of clogging the filters. Two layers of epoxy resin are sufficient to fix contamination with a factor of 8600; their thickness (about 30 μm) nevertheless limits their use to this application. To reduce diffusion of radionuclides (Co-60 and Cs-137), polyurethane resins were chosen with which it is possible to obtain a thick coating in only a short time. Their properties of fixing the contamination, retaining of radionuclides and resistance to impact, have been assessed. First application of the procedure on a contaminated metallic bellow coming from dismantling of nuclear reactor, has been carried out

  9. Isolation of Metals from Liquid Wastes: Reactive Scavenging in Turbulent Thermal Reactors

    Energy Technology Data Exchange (ETDEWEB)

    William Linak

    2004-12-16

    Sorption of cesium and strontium on kaolinite powders was investigated as a means to minimize the emissions of these metals during certain high temperature processes currently being developed to isolate and dispose of radiological and mixed wastes. In this work, non-radioactive aqueous cesium acetate or strontium acetate was atomized down the center of a natural gas flame supported on a variable-swirl burner in a refractory-lined laboratory-scale combustion facility. Kaolinite powder was injected at a post-flame location in the combustor. Cesium readily vaporizes in the high temperature regions of the combustor, but was reactively scavenged onto dispersed kaolinite. Global sorption mechanisms of cesium vapor on kaolinite were quantified, and are related to those available in the literature for sodium and lead. Both metal adsorption and substrate deactivation steps are important, and so there is an optimum temperature, between 1400 and 1500 K, at which maximum sorption occurs. The presence of chlorine inhibits cesium sorption. In contrast to cesium, and in the absence of chlorine, strontium was only partially vaporized and was, therefore, only partially scavengeable. The strontium data did not allow quantification of global kinetic mechanisms of interaction, although equilibrium arguments provided insight into the effects of chlorine on strontium sorption. These results have implications for the use of sorbents to control cesium and strontium emissions during high temperature waste processing including incineration and vitrification.

  10. New immobilisation methods for radioactive waste. Metal composite and other systems

    International Nuclear Information System (INIS)

    Ozhovan, M.

    2004-01-01

    New immobilisation hosts and technologies are presented. Some new approaches as crystalline hosts, polyphase crystalline forms (SYNROC), polyphase forms (composites), metal matrix immobilisation are discussed. The potential use and chemical properties and radiation durability of minerals Monazite, Zircon and Zirconolite, Hollandite, Apatites, Britolite and NZP are presented. The most famous polyphase ceramic for nuclear waste immobilisation is SYNROC. The properties of SYNROC and a comparison of SYNROC matrix parameters with nuclear waste glasses is made. Glass composites may be used to immobilise long-lived radionuclides (e.g. An) by incorporating them into the more durable crystalline phases, whereas the short-lived radionuclides may be accommodated in the less durable vitreous phase. An example of such glass composite is so-called SYNROC-glass, which is a glass-composite material with SYNROC crystalline phases in a vitreous matrix. The new technological approaches discussed in the paper are: melting, sintering, thermochemical method. The features and advantages of metal matrix immobilization are also discussed

  11. Technical assessment of processes to enable recycling of low-level contaminated metal waste

    Energy Technology Data Exchange (ETDEWEB)

    Reimann, G.A.

    1991-10-01

    Accumulations of metal waste exhibiting low levels of radioactivity (LLCMW) have become a national burden, both financially and environmentally. Much of this metal could be considered as a resource. The Department of Energy was assigned the task of inventorying and classifying LLCMW, identifying potential applications, and applying and/or developing the technology necessary to enable recycling. One application for recycled LLCMW is high-quality canisters for permanent repository storage of high-level waste (HLW). As many as 80,000 canisters will be needed by 2035. Much of the technology needed to decontaminate LLCMW has already been developed, but no integrated process has been described, even on a pilot scale, for recycling LLCMW into HLW canisters. This report reviews practices for removal of radionuclides and for producing low carbon stainless steel. Contaminants that readily form oxides may be reduced to below de minimis levels and combined with a slag. Most of the radioactivity remaining in the ingot is concentrated in the inclusions. Radionuclides that chemically resemble the elements that comprise stainless steel can not be removed effectively. Slag compositions, current melting practices, and canister fabrication techniques were reviewed.

  12. Optimization of process parameters for heavy metals biosorption onto mustard waste biomass

    Directory of Open Access Journals (Sweden)

    Nemeş Lăcrămioara (Negrilă

    2016-01-01

    Full Text Available Mustard waste biomass was tested as a biosorbent for the removal of Pb(II, Zn(II and Cd(II from aqueous solution. This strategy may be a sustainable option for the utilization of such wastes. The influence of the most important operating parameters of the biosorption process was analyzed in batch experiments, and optimal conditions were found to include initial solution pH 5.5, 5.0 g biosorbent/L, 2 hours of contact time and high temperature. Kinetics analyses show that the maximum of biosorption was quickly reached and could be described by a pseudo-second order kinetic model. The equilibrium data were well fitted by the Langmuir model, and the highest values of maximum biosorption capacity were obtained with Pb(II, followed by Zn(II and Cd(II. The thermodynamic parameters of the biosorption process (ΔG, ΔH and ΔS were also evaluated from isotherms. The results of this study suggest that mustard waste biomass can be used for the removal of heavy metals from aqueous media.

  13. Effect of bacterial inoculants on phytomining of metals from waste incineration bottom ash.

    Science.gov (United States)

    Rosenkranz, Theresa; Kidd, Petra; Puschenreiter, Markus

    2018-03-01

    Waste incineration bottom ash is considered a secondary resource for valuable trace elements (TE), which is currently neglected in most European countries. Phytomining could potentially recover valuable TE from such waste materials but is still at an exploratory stage with many challenges. The use of bioaugmentation to improve plant growth and TE accumulation of metal-tolerant high biomass plants growing on waste incineration bottom ash was evaluated. Bacterial strains that were previously isolated from rhizosphere, roots and contaminated soil were selected according to their plant growth promoting characteristics and tolerance to the bottom ash substrate. Those selected bacterial strains were tested for their beneficial effects on Nicotiana tabacum and Salix smithiana with regards to phytomining. The rhizobacterial strain Rhodococcus erythropolis P30 enhanced the shoot dry weight of N. tabacum by on average 57% compared to the control plants. Several bacterial inoculants enhanced biomass production and the nutritional status of S. smithiana. Moreover, those bacterial strains previously described to enhance biomass production of N. tabacum and members of the Salicaceae on TE-contaminated soils, also enhanced biomass production of these species on bottom ash. However, bacterial inoculants could not enhance trace element accumulation in plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Bio-leaching of toxic metals from geothermal waste. A preliminary engineering analysis

    Energy Technology Data Exchange (ETDEWEB)

    Dobryn, D.G.; Brisson, A.L.; Lee, C.M.; Roll, S.M.

    1986-02-01

    The feasibility of a biological facility to treat geothermal sludge from a base case 50-MW double-flash geothermal power plant in the Imperial Valley, California was evaluated. The effect of sludge and nutrient concentration, agitation air bubbling and sterility on the rate of metal solubilization by the bacteria Thiobacillus thiooxidans and ferrooxidans was examined. All experiments were performed in batch flasks and monitored daily for bacterial growth. T. Thiooxidans leached 36% of the zinc in the sludge after 288 hr but leached little chromium. T. ferrooxidans removed 60% of the chromium in the sludge after 250 hr but did not leach zinc. Sludge to medium ratios of greater than 10% were toxic to the microorganisms studied. the experimental results were used to design a biological solid-waste treatment plant. The design basis used was 5 wt % sludge in the leaching vessel with a residence time of 10 days. The non-regulated waste resulting from the treatment plant could be used for land fill or construction materials. The total capital cost for the bio-leaching plant is $3.3 million with an annual operating cost of $690,000. The total cost of this plant is about 0.2 cents/kWh of electricity produced, which is essentially the same cost as hauling the solid waste to a hazardous disposal site. This cost accounts for about 5% of the cost of producing electricity from geothermal power (4 cent/kWh).

  15. Systems engineering approach for the reuse of metallic waste from NPP decommissioning and dose evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Hyung Woo; Kim, Chang Lak [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2017-03-15

    The oldest commercial reactor in South Korea, Kori-1 Nuclear Power Plant (NPP), will be shut down in 2017. Proper treatment for decommissioning wastes is one of the key factors to decommission a plant successfully. Particularly important is the recycling of clearance level or very low level radioactively contaminated metallic wastes, which contributes to waste minimization and the reduction of disposal volume. The aim of this study is to introduce a conceptual design of a recycle system and to evaluate the doses incurred through defined work flows. The various architecture diagrams were organized to define operational procedures and tasks. Potential exposure scenarios were selected in accordance with the recycle system, and the doses were evaluated with the RESRAD-RECYCLE computer code. By using this tool, the important scenarios and radionuclides as well as impacts of radionuclide characteristics and partitioning factors are analyzed. Moreover, dose analysis can be used to provide information on the necessary decontamination, radiation protection process, and allowable concentration limits for exposure scenarios.

  16. Self-healing properties of recycled asphalt mixtures containing metal waste: An approach through microwave radiation heating.

    Science.gov (United States)

    González, A; Norambuena-Contreras, J; Storey, L; Schlangen, E

    2018-05-15

    The concept of self-healing asphalt mixtures by bitumen temperature increase has been used by researchers to create an asphalt mixture with crack-healing properties by microwave or induction heating. Metals, normally steel wool fibers (SWF), are added to asphalt mixtures prepared with virgin materials to absorb and conduct thermal energy. Metal shavings, a waste material from the metal industry, could be used to replace SWF. In addition, reclaimed asphalt pavement (RAP) could be added to these mixtures to make a more sustainable road material. This research aimed to evaluate the effect of adding metal shavings and RAP on the properties of asphalt mixtures with crack-healing capabilities by microwave heating. The research indicates that metal shavings have an irregular shape with widths larger than typical SWF used with asphalt self-healing purposes. The general effect of adding metal shavings was an improvement in the crack-healing of asphalt mixtures, while adding RAP to mixtures with metal shavings reduced the healing. The average surface temperature of the asphalt samples after microwave heating was higher than temperatures obtained by induction heating, indicating that shavings are more efficient when mixtures are heated by microwave radiation. CT scan analysis showed that shavings uniformly distribute in the mixture, and the addition of metal shavings increases the air voids. Overall, it is concluded that asphalt mixtures with RAP and waste metal shavings have the potential of being crack-healed by microwave heating. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Road soil retention of heavy metals leached from Municipal Solid Waste Incinerator bottom ash used in road construction

    OpenAIRE

    BOUVET, M

    2003-01-01

    Economic stakes of raw materials and harmful effects linked to waste landfill lead to the re-use of alternative materials like Municipal Solid Waste Incinerator (MSWI) bottom ash in road construction . MSWI bottom ash has a high heavy metal content, which can leach and infiltrate into the underlying soil, under the effect of rainfall infiltration through the road. The assessment of MSWI bottom ash re-use eco-compatibility implies to study the solubility and the retention of heavy metals in th...

  18. Precious metals and rare earth elements in municipal solid waste--sources and fate in a Swiss incineration plant.

    Science.gov (United States)

    Morf, Leo S; Gloor, Rolf; Haag, Olaf; Haupt, Melanie; Skutan, Stefan; Di Lorenzo, Fabian; Böni, Daniel

    2013-03-01

    In Switzerland many kinds of waste, e.g. paper, metals, electrical and electronic equipment are separately collected and recycled to a large extent. The residual amount of municipal solid waste (MSW) has to be thermally treated before final disposal. Efforts to recover valuable metals from incineration residues have recently increased. However, the resource potential of critical elements in the waste input (sources) and their partitioning into recyclable fractions and residues (fate) is unknown. Therefore, a substance flow analysis (SFA) for 31 elements including precious metals (Au, Ag), platinum metal group elements (Pt, Rh) and rare earth elements (La, Ce, etc.) has been conducted in a solid waste incinerator (SWI) with a state-of-the-art bottom ash treatment according to the Thermo-Re® concept. The SFA allowed the determination of the element partitioning in the SWI, as well as the elemental composition of the MSW by indirect analysis. The results show that the waste-input contains substantial quantities of precious metals, such as 0.4 ± 0.2mg/kg Au and 5.3 ± 0.7 mg/kg Ag. Many of the valuable substances, such as Au and Ag are enriched in specific outputs (e.g. non-ferrous metal fractions) and are therefore recoverable. As the precious metal content in MSW is expected to rise due to its increasing application in complex consumer products, the results of this study are essential for the improvement of resource recovery in the Thermo-Re® process. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Chemical associations and mobilization of heavy metals in fly ash from municipal solid waste incineration.

    Science.gov (United States)

    Weibel, Gisela; Eggenberger, Urs; Schlumberger, Stefan; Mäder, Urs K

    2017-04-01

    This study focusses on chemical and mineralogical characterization of fly ash and leached filter cake and on the determination of parameters influencing metal mobilization by leaching. Three different leaching processes of fly ash from municipal solid waste incineration (MSWI) plants in Switzerland comprise neutral, acidic and optimized acidic (+ oxidizing agent) fly ash leaching have been investigated. Fly ash is characterized by refractory particles (Al-foil, unburnt carbon, quartz, feldspar) and newly formed high-temperature phases (glass, gehlenite, wollastonite) surrounded by characteristic dust rims. Metals are carried along with the flue gas (Fe-oxides, brass) and are enriched in mineral aggregates (quartz, feldspar, wollastonite, glass) or vaporized and condensed as chlorides or sulphates. Parameters controlling the mobilization of neutral and acidic fly ash leaching are pH and redox conditions, liquid to solid ratio, extraction time and temperature. Almost no depletion for Zn, Pb, Cu and Cd is achieved by performing neutral leaching. Acidic fly ash leaching results in depletion factors of 40% for Zn, 53% for Cd, 8% for Pb and 6% for Cu. The extraction of Pb and Cu are mainly limited due to a cementation process and the formation of a PbCu 0 -alloy-phase and to a minor degree due to secondary precipitation (PbCl 2 ). The addition of hydrogen peroxide during acidic fly ash leaching (optimized acidic leaching) prevents this reduction through oxidation of metallic components and thus significantly higher depletion factors for Pb (57%), Cu (30%) and Cd (92%) are achieved. The elevated metal depletion using acidic leaching in combination with hydrogen peroxide justifies the extra effort not only by reduced metal loads to the environment but also by reduced deposition costs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Application of insoluble tannin to recovery of uranium, TRU and heavy metals elements form radioactive liquid waste

    International Nuclear Information System (INIS)

    Hamaguchi, Kazuhiko; Shirato, Wataru; Nakamura, Yasuo; Matsumura, Tatsuro; Takeshita, Kenji; Nakano, Yoshio

    1999-01-01

    Mitsubishi Nuclear Fuel Co., Ltd. (MNF) has developed a new adsorbent, TANNIX (tread mark), for the recovery of uranium, TRU and heavy metal elements in the liquid waste, in which TANNIX derived from a natural tannin polymer. TANNIX has same advantages that handling is easier than that of standard IX-resin, and that the volume of secondary waste is reduced by burning the used TANNIX. We have replaced its radioactive liquid waste treatment system from the conventional co-precipitation process to adsorption process by using TANNIX. TANNIX was founded to be more effective for the recovery of Pu, TRU, and hexavalent chromium Cr-(VI) as well as Uranium. (author)

  1. Fiscal Year 2010 Summary Report on the Epsilon-Metal Phase as a Waste Form for 99 Tc

    Energy Technology Data Exchange (ETDEWEB)

    Strachan, Denis M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Crum, Jarrod V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buck, Edgar C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Riley, Brian J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zumhoff, Mac R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2010-09-30

    Epsilon metal (ε-metal) is generated in nuclear fuel during irradiation. This metal consists of Pd, Ru, Rh, Mo, and some Te. These accumulate at the UO2 grain boundaries as small (ca 5 µm) particles. These metals have limited solubility in the acid used to dissolve fuel during reprocessing and in typical borosilicate glass. These must be treated separately to improve overall waste loading in glass. This low solubility and their survival in 2 Gy-old natural reactors led us to investigate them as a waste form for the immobilization of 99Tc and 107Pd, two very long-lived isotopes.

  2. High-sensitive detection by direct interrogation of 14 MeV Acc neutrons, (1). Uranium-contained metal matrix in a waste dram

    International Nuclear Information System (INIS)

    Haruyama, Mitsuo; Takase, Misao; Tobita, Hiroshi; Mori, Takamasa

    2004-01-01

    Previously, authors reported that the 14 MeV-neutron direct interrogation method has made possible measure for the discrimination of clearance levels of concrete solidification uranium waste. In this paper, applicability of the method to metal waste matrix is discussed based on the results of simulation experiments by the continuation energy Monte Carlo calculation code (MVP). The problem is that self-neutron moderation effect in a waste cannot be expected when a waste matrix is metal. To solve this, a moderator is adopted so as to surround a metal waste drum and to slow down suitably a 14 MeV neutrons. The simulation calculation showed that this effect is satisfactorily large. The detection limit of radioactivity concentration to 4.5% enriched uranium has been found to be 0.0973 Bq/g in the metal waste model of 215.59 kg gross weight, in which 61 pipes are stuffed into its drum. Moreover, the position-dependent sensitivity difference in a metal waste drum can be settled as small as to ±13.5%. In conclusion, it can be said that 14 MeV-neutron direct interrogation method can be applied to the waste of a metal system: the detection sensitivity is high enough and the position-dependent sensitivity difference is small admittedly. Hence the method can be applied also to discrimination measurement of the clearance level of metal uranium waste. (author)

  3. Metal content in fruit-bodies and mycorrhizas of Pisolithus arrhizus from zinc wastes in Poland

    Directory of Open Access Journals (Sweden)

    Katarzyna Turnau

    2014-08-01

    Full Text Available Pisolithus arrhizus has been selected for investigation as one of the ectomycorrhizal species most resistant to stress factors. Metal content in fruit-bodies and mycorrhizas was estimated to evaluate their role as bioindicators and to check whether mycorrhizas have any special properties for heavy metal accumulation. Fruit-bodies and mycorrhizas were collected from zinc wastes in Katowice-Wełnowiec and analyzed using conventional atomic absorption spectroscopy and energy dispersive spectroscopy accompanying scanning electron microscopy. Differences in tendencies to accumulate metals within sporophores and mycorrhizas were found. The fruit-bodies accumulated Al (up to 640 µg g-1, while high concentrations of Al, Zn, Fe, Ca and Si were noted in the outer mantle of the mycorrhizas. in the material secreted and in the mycelium wali. The content of elements varied depending on the agę of mycorrhizas. The ability of extramatrical mycelium and hyphae forming mycorrhizal mantle to immobilize potentially toxic elements might indicate biofiltering properties though thc next step should include investigations on ability of the fungus to prevent element uptake by the plant.

  4. Recovering metallic fractions from waste electrical and electronic equipment by a novel vibration system.

    Science.gov (United States)

    Habib, Muddasar; Miles, Nicholas J; Hall, Philip

    2013-03-01

    The need to recover and recycle valuable resources from Waste Electrical and Electronic Equipment (WEEE) is of growing importance as increasing amounts are generated due to shorter product life cycles, market expansions, new product developments and, higher consumption and production rates. The European Commission (EC) directive, 2002/96/EC, on WEEE became law in UK in January 2007 setting targets to recover up to 80% of all WEEE generated. Printed Wire Board (PWB) and/or Printed Circuit Board (PCB) is an important component of WEEE with an ever increasing tonnage being generated. However, the lack of an accurate estimate for PCB production, future supply and uncertain demands of its recycled materials in international markets has provided the motivation to explore different approaches to recycle PCBs. The work contained in this paper focuses on a novel, dry separation methodology in which vertical vibration is used to separate the metallic and non-metallic fractions of PCBs. When PCBs were comminuted to less than 1mm in size, metallic grades as high as 95% (measured by heavy liquid analysis) could be achieved in the recovered products. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. PHYSICO-CHEMICAL PROPERTIES OF THE SOLID AND LIQUID WASTE PRODUCTS FROM THE HEAVY METAL CONTAMINATED ENERGY CROPS GASIFICATION PROCESS

    Directory of Open Access Journals (Sweden)

    Sebastian Werle

    2017-02-01

    Full Text Available The paper presents the results of basic physico-chemical properties of solid (ash and liquid (tar waste products of the gasification process of the heavy metal contaminated energy crops. The gasification process has carried out in a laboratory fixed bed reactor. Three types of energy crops: Miscanthus x giganteus, Sida hermaphrodita and Spartina Pectinata were used. The experimental plots were established on heavy metal contaminated arable land located in Bytom (southern part of Poland, Silesian Voivodship.

  6. Comparison of Collection Schemes of Municipal Solid Waste Metallic Fraction: The Impacts on Global Warming Potential for the Case of the Helsinki Metropolitan Area, Finland

    Directory of Open Access Journals (Sweden)

    Kari Heiskanen

    2012-10-01

    Full Text Available In this research article the sustainability of different practices to collect the metal fraction of household waste in the Helsinki metropolitan area, Finland is examined. The study is carried out by calculating and comparing the greenhouse gas reduction potential of optional practices for collecting the metal fraction of household waste in the Helsinki metropolitan area, Finland. In order to locate the greenhouse gas reduction potential of the separate collection of the metallic fraction of municipal solid waste (MSW collected from residential sources, a comparative carbon footprint analysis using Life Cycle Assessment (LCA on six different waste management scenarios is carried out. The modeled system consisted of a waste collection system, transportation, and different waste management alternatives, including on-site separation, separation at the waste management facility as well as metallurgical recovery of separated scrap. The results show that, in terms of greenhouse gas emissions, separate collection and recycling of the metallic fraction of solid MSW at residential properties is the preferable option compared to a scenario with no source sorting and incineration of everything. According to this research scenario where the metal fraction of solid household waste was not source-separated or collected separately have clearly higher greenhouse gas emissions compared to all the other scenarios with separate collection for metals. In addition, metal recycling by regional collection points has considerably lower greenhouse gas emission potential than metal recycling by collection directly from residential properties.

  7. Contamination and risk of heavy metals in soils and sediments from a typical plastic waste recycling area in North China.

    Science.gov (United States)

    Tang, Zhenwu; Zhang, Lianzhen; Huang, Qifei; Yang, Yufei; Nie, Zhiqiang; Cheng, Jiali; Yang, Jun; Wang, Yuwen; Chai, Miao

    2015-12-01

    Plastic wastes are increasingly being recycled in many countries. However, available information on the metals released into the environment during recycling processes is rare. In this study, the contamination features and risks of eight heavy metals in soils and sediments were investigated in Wen'an, a typical plastic recycling area in North China. The surface soils and sediments have suffered from moderate to high metal pollution and in particular, high Cd and Hg pollution. The mean concentrations of Cd and Hg were 0.355 and 0.408 mg kg(-1), respectively, in the soils and 1.53 and 2.10 mg kg(-1), respectively, in the sediments. The findings suggested that there is considerable to high potential ecological risks in more than half of the soils and high potential ecological risk in almost all sediments. Although the health risk levels from exposure to soil metals were acceptable for adults, the non-carcinogenic risks to local children exceeded the acceptable level. Source assessment indicated that heavy metals in soils and sediments were mainly derived from inputs from poorly controlled plastic waste recycling operations in this area. The results suggested that the risks associated with heavy metal pollution from plastic waste recycling should be of great concern. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Spatial assessment of potential ecological risk of heavy metals in soils from informal e-waste recycling in Ghana

    Directory of Open Access Journals (Sweden)

    Vincent Nartey Kyere

    2017-10-01

    Full Text Available The rapidly increasing annual global volume of e-waste, and of its inherently valuable fraction, has created an opportunity for individuals in Agbogbloshie, Accra, Ghana to make a living by using unconventional, uncontrolled, primitive and crude procedures to recycle and recover valuable metals from this waste. The current form of recycling procedures releases hazardous fractions, such as heavy metals, into the soil, posing a significant risk to the environment and human health. Using a handheld global positioning system, 132 soil samples based on 100 m grid intervals were collected and analysed for cadmium (Cd, chromium (Cr, copper (Cu, mercury (Hg, lead (Pb and zinc (Zn. Using geostatistical techniques and sediment quality guidelines, this research seeks to assess the potential risk these heavy metals posed to the proposed Korle Ecological Restoration Zone by informal e-waste processing site in Agbogbloshie, Accra, Ghana. Analysis of heavy metals revealed concentrations exceeded the regulatory limits of both Dutch and Canadian soil quality and guidance values, and that the ecological risk posed by the heavy metals extended beyond the main burning and dismantling sites of the informal recyclers to the school, residential, recreational, clinic, farm and worship areas. The heavy metals Cr, Cu, Pb and Zn had normal distribution, spatial variability, and spatial autocorrelation. Further analysis revealed the decreasing order of toxicity, Hg>Cd>Pb> Cu>Zn>Cr, of contributing significantly to the potential ecological risk in the study area.

  9. Spatial assessment of potential ecological risk of heavy metals in soils from informal e-waste recycling in Ghana.

    Science.gov (United States)

    Kyere, Vincent Nartey; Greve, Klaus; Atiemo, Sampson Manukure; Ephraim, James

    2017-01-01

    The rapidly increasing annual global volume of e-waste, and of its inherently valuable fraction, has created an opportunity for individuals in Agbogbloshie, Accra, Ghana to make a living by using unconventional, uncontrolled, primitive and crude procedures to recycle and recover valuable metals from this waste. The current form of recycling procedures releases hazardous fractions, such as heavy metals, into the soil, posing a significant risk to the environment and human health. Using a handheld global positioning system, 132 soil samples based on 100 m grid intervals were collected and analysed for cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), lead (Pb) and zinc (Zn). Using geostatistical techniques and sediment quality guidelines, this research seeks to assess the potential risk these heavy metals posed to the proposed Korle Ecological Restoration Zone by informal e-waste processing site in Agbogbloshie, Accra, Ghana. Analysis of heavy metals revealed concentrations exceeded the regulatory limits of both Dutch and Canadian soil quality and guidance values, and that the ecological risk posed by the heavy metals extended beyond the main burning and dismantling sites of the informal recyclers to the school, residential, recreational, clinic, farm and worship areas. The heavy metals Cr, Cu, Pb and Zn had normal distribution, spatial variability, and spatial autocorrelation. Further analysis revealed the decreasing order of toxicity, Hg>Cd>Pb> Cu>Zn>Cr, of contributing significantly to the potential ecological risk in the study area.

  10. Spatial assessment of potential ecological risk of heavy metals in soils from informal e-waste recycling in Ghana

    Science.gov (United States)

    Greve, Klaus; Atiemo, Sampson Manukure

    2017-01-01

    The rapidly increasing annual global volume of e-waste, and of its inherently valuable fraction, has created an opportunity for individuals in Agbogbloshie, Accra, Ghana to make a living by using unconventional, uncontrolled, primitive and crude procedures to recycle and recover valuable metals from this waste. The current form of recycling procedures releases hazardous fractions, such as heavy metals, into the soil, posing a significant risk to the environment and human health. Using a handheld global positioning system, 132 soil samples based on 100 m grid intervals were collected and analysed for cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), lead (Pb) and zinc (Zn). Using geostatistical techniques and sediment quality guidelines, this research seeks to assess the potential risk these heavy metals posed to the proposed Korle Ecological Restoration Zone by informal e-waste processing site in Agbogbloshie, Accra, Ghana. Analysis of heavy metals revealed concentrations exceeded the regulatory limits of both Dutch and Canadian soil quality and guidance values, and that the ecological risk posed by the heavy metals extended beyond the main burning and dismantling sites of the informal recyclers to the school, residential, recreational, clinic, farm and worship areas. The heavy metals Cr, Cu, Pb and Zn had normal distribution, spatial variability, and spatial autocorrelation. Further analysis revealed the decreasing order of toxicity, Hg>Cd>Pb> Cu>Zn>Cr, of contributing significantly to the potential ecological risk in the study area. PMID:29056034

  11. Microbial assisted phyto extraction of metals and growth of soybean (glycine max l. merrill) on industrial waste water contaminated soil

    International Nuclear Information System (INIS)

    Ali, I.; Bano, A.

    2012-01-01

    Pots experiments were made to investigate the role of effective microorganisms (EM) in improving phyto extraction of metals (Cd/sup +2/ and Mn/sup +2/) and growth of soybean plant in industrial waste water polluted soil. Waste water applications to soil were made in four different dilutions (i.e. 25%, 50%, 75% and 100%). Effective microorganisms were added into waste water prior to application. Effect of treatments on growth parameters was studied. The Cd/sup +2/ and Mn/sup +2/ concentrations in different parts of plant were measured by Atomic Absorption Spectrophotometer. Plant height significantly increased at all treatments except at 25% waste water treatment. Plant dry biomass and oil contents in seed significantly increased with all treatments compared to control but were higher at low concentration of waste water. Waste water treatments significantly increased the Cd and Mn accumulation in plant while inoculation of EM further enhanced the metals accumulation. The maximum accumulation of Cd and Mn found in plant treated with 100% waste water in combination with effective microorganisms. At harvest, the Cd/sup +2/ concentration decreased in leaves but increased in roots followed by stem > seeds, while, Mn/sup +2/ accumulation increased in leaves followed by roots > stem > seeds. Conclusively, EM enhanced the phyto extraction of Cd and Mn and also increased the oil contents in soybean on polluted soil. These findings suggest further investigation to find out a suitable concentration of industrial waste water in combination with EM for better growth of soybean and improving phyto extraction of metals. (author)

  12. Interaction of pristine hydrotalcite-like layered double hydroxides ...

    Indian Academy of Sciences (India)

    Metal oxides in general have surface acidic sites, but for exceptional circumstances, are not expected to mineralize CO2. Given their intrinsic basicity and an expandable interlayer gallery, the hydrotalcite-like layered double hydroxides (LDHs) are expected to be superior candidate materials for CO2 mineralization.

  13. Systematic review of potential health risks posed by pharmaceutical, occupational and consumer exposures to metallic and nanoscale aluminum, aluminum oxides, aluminum hydroxide and its soluble salts

    Science.gov (United States)

    Willhite, Calvin C.; Karyakina, Nataliya A.; Yokel, Robert A.; Yenugadhati, Nagarajkumar; Wisniewski, Thomas M.; Arnold, Ian M. F.; Momoli, Franco; Krewski, Daniel

    2016-01-01

    leads to intrinsic apoptosis. In contrast, the toxicity of the insoluble Al oxides depends primarily on their behavior as particulates. Aluminum has been held responsible for human morbidity and mortality, but there is no consistent and convincing evidence to associate the Al found in food and drinking water at the doses and chemical forms presently consumed by people living in North America and Western Europe with increased risk for Alzheimer’s disease (AD). Neither is there clear evidence to show use of Al-containing underarm antiperspirants or cosmetics increases the risk of AD or breast cancer. Metallic Al, its oxides, and common Al salts have not been shown to be either genotoxic or carcinogenic. Aluminum exposures during neonatal and pediatric parenteral nutrition (PN) can impair bone mineralization and delay neurological development. Adverse effects to vaccines with Al adjuvants have occurred; however, recent controlled trials found that the immunologic response to certain vaccines with Al adjuvants was no greater, and in some cases less than, that after identical vaccination without Al adjuvants. The scientific literature on the adverse health effects of Al is extensive. Health risk assessments for Al must take into account individual co-factors (e.g., age, renal function, diet, gastric pH). Conclusions from the current review point to the need for refinement of the PTWI, reduction of Al contamination in PN solutions, justification for routine addition of Al to vaccines, and harmonization of OELs for Al substances. PMID:25233067

  14. Irradiation effect on leaching behavior and form of heavy metals in fly ash of municipal solid waste incinerator

    International Nuclear Information System (INIS)

    Nam, Sangchul; Namkoong, Wan

    2012-01-01

    Highlights: ► No research has been done to examine effect of electron beam irradiation on leaching behavior of heavy metals in fly ash. ► Electron beam irradiation on fly ash had significant effect on heavy metal leaching. ► Leaching potential of heavy metals in fly ash differed among metal species tested (Pb, Zn, Cu). ► Metal forms in the ash were analyzed to explain the difference. ► The difference could be explained by metal form change. - Abstract: Fly ash from a municipal solid waste incinerator (MSWI) is commonly classified as hazardous waste. High-energy electron beam irradiation systems have gained popularity recently as a clean and promising technology to remove environmental pollutants. Irradiation effects on leaching behavior and form of heavy metals in MSWI fly ash have not been investigated in any significant detail. An electron beam accelerator was used in this research. Electron beam irradiation on fly ash significantly increased the leaching potential of heavy metals from fly ash. The amount of absorbed dose and the metal species affected leaching behavior. When electron beam irradiation intensity increased gradually up to 210 kGy, concentration of Pb and Zn in the leachate increased linearly as absorbed dose increased, while that of Cu underwent no significant change. Concentration of Pb and Zn in the leachate increased up to 15.5% (10.7 mg/kg), and 35.6% (9.6 mg/kg) respectively. However, only 4.8% (0.3 mg/kg) increase was observed in the case of Cu. The results imply that irradiation has significant effect on the leaching behavior of heavy metals in fly ash, and the effect is quite different among the metal species tested in this study. A commonly used sequential extraction analysis which can classify a metal species into five forms was conducted to examine any change in metal form in the irradiated fly ash. Notable change in metal form in fly ash was observed when fly ash was irradiated. Change in Pb form was much greater than that of

  15. Use of scalp hair as indicator of human exposure to heavy metals in an electronic waste recycling area

    Energy Technology Data Exchange (ETDEWEB)

    Wang Thanh; Fu Jianjie; Wang Yawei; Liao Chunyang [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, P.O. Box 2871, Beijing 100085 (China); Tao Yongqing [Shangyu Environmental Protection Bureau, 312300 Shaoxing, Zhejiang (China); Jiang Guibin, E-mail: gbjiang@rcees.ac.c [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, P.O. Box 2871, Beijing 100085 (China)

    2009-08-15

    Scalp hair samples were collected at an electronic waste (e-waste) recycling area and analyzed for trace elements and heavy metals. Elevated levels were found for Cu and Pb with geometric means (GMs) at 39.8 and 49.5 mug/g, and the levels of all elements were found in the rank order Pb > Cu >> Mn > Ba > Cr > Ni > Cd > As > V. Besides Cu and Pb, Cd (GM: 0.518 mug/g) was also found to be significantly higher compared to that in hair samples from control areas. Differences with age, gender, residence status and villages could be distinguished for most of the elements. The high levels of Cd, Cu and Pb were likely found to be originated from e-waste related activities, and specific sources were discussed. This study shows that human scalp hair could be a useful biomarker to assess the extent of heavy metal exposure to workers and residents in areas with intensive e-waste recycling activities. - Human scalp hair samples can be used to indicate environmental and occupational exposure of heavy metals due to intensive electronic waste recycling activities.

  16. Development of Chemosorbent Based on Metallic Waste for Cleaning Mine Water From Molybdenum

    Directory of Open Access Journals (Sweden)

    Alexander Evgenyevich Isakov

    2018-01-01

    Full Text Available The article presents the results of hydrochemical studies of water objects, located in the impact zone of one of the largest mining enterprises in the Russian Federation – JSC “Apatite”. According to the monitoring studies, the source of surface water pollution with molybdenum was determined, geochemical assessment of the molybdenum transformation in the system “ore-bearing rocks – mine water – surface water” was performed. In order to reduce the technogenic load on the surface water located in the considered area, the way of large-tonnage mine waters purificationfrom molybdenum was proposed. The method involves using the chemical sorbent based on waste metals. The method of sewage purificationwill allow solving one of the key environmental problems of the considered enterprise and, in addition, to improve the environmental situation in the considered area as well as the quality of the local population life.

  17. Extraction of heavy metals from municipal solid waste incinerator (MSWI) bottom ash with organic solutions.

    Science.gov (United States)

    Van Gerven, T; Cooreman, H; Imbrechts, K; Hindrix, K; Vandecasteele, C

    2007-02-09

    Municipal solid waste incinerator (MSWI) bottom ash often cannot be recycled as construction material in Flanders, because leaching of Cu exceeds the limit value of 0.5mg/kg. Leaching of other components such as Mo and Sb is critical as well, but limit values for these elements are to date only informal. A treatment technique was investigated to lower pollutant leaching: extraction with solutions of organic complexants to remove Cu. Six different solutions were used, of which washing with citric acid and ammonium citrate decreases Cu leaching to below the limit value. Extraction was then performed with different concentrations of ammonium citrate. Subsequent washing of the extracted material with distilled water appears to be vital to remove all residual ammonium citrate. Extraction with a 0.2M solution of ammonium citrate followed by three washing steps decreases metal leaching to below the limit values.

  18. Removal heavy metals and sulphate from waste waters by sulphate-reducing bacteria

    Directory of Open Access Journals (Sweden)

    Kušnierová Mária

    2000-09-01

    Full Text Available This article is devoted to the process of bacterial sulphate reduction, which is used to removal of heavy metals and sulphate ions from waste waters.The life of animals and plants depends on the existence of microscopic organisms – microorganisms (MO, which play an important role in cycle changes of biogenic elements on the earth. The sulphur cycle in the nature is considered as one of the oldest and most significant biological systems (Fig. 1. The sulphate-reducing bacteria (SRB miss the assimilatory part of the cycle and produce sulphides. The microbial population of this dissimilatory part is called “sulfuretum”. The SRB can be found in anaerobic mud and sediments of freshwater, thermal or non-thermal sulphur springs, mining waters from sulphide deposits, oil deposits, sea and ocean beds, and in the gastrointestinal tract of man and animals. The SRB represent a group of chemoorganotrophic, strictly anaerobic and gramnegative bacteria, which exhibit a great morphological and physiological diversity. Despite of their considerable morphological variety, they have one property in common, which is the ability to utilise preferentially sulphates (occasionally sulphites, thiosulphates, tetrathionates as electron acceptors, which are reduced to sulphides, during anaerobic respiration. The electron donors in these processes are simple organic compounds as lactate, malate, etc.,(heterotrophically reduction or gaseous hydrogen (autotrophically reduction. SRB can produce a considerable amount of hydrogen sulphide, which reacts easily in aqueous solution with the cations of heavy metals, forming metal sulphides that have low solubility. The bacterial sulphate reduction can be used for the treatment of acid mine drainage waters, which is considered to be the major problem associated with mining activities.In order to remove heavy metals from waste waters, e.g., from galvanizing plants, mine waters (Smolnik, Šobov locality and metallurgic plants (works

  19. Determination of metal additives and bromine in recycled thermoplasts from electronic waste by TXRF analysis.

    Science.gov (United States)

    Fink, H; Panne, U; Theisen, M; Niessner, R; Probst, T; Lin, X

    2000-01-01

    A new method for analysis of metal additives in recycled thermoplasts from electronic waste was developed, based on dissolving the samples in an organic solvent and subsequent analysis of the corresponding solutions or suspensions by total-reflection X-ray fluorescence spectroscopy (TXRF). The procedure proved to be considerably less time consuming than the conventional digestion of the polymer matrix. Additives containing Ti, Zn, Br, Cd, Sn, Sb, and Pb were analyzed in a hundred randomly selected samples from recycling, which provided an overview of the range of elemental concentrations in thermoplasts utilized for consumer electronics. The results were validated independently by instrumental neutron activation analysis (INAA), subsequent regression analysis confirmed the trueness of the chosen approach.

  20. Determining heavy metals in spent compact fluorescent lamps (CFLs) and their waste management challenges: some strategies for improving current conditions.

    Science.gov (United States)

    Taghipour, Hassan; Amjad, Zahra; Jafarabadi, Mohamad Asghari; Gholampour, Akbar; Norouz, Prviz

    2014-07-01

    From environmental viewpoint, the most important advantage of compact fluorescent lamps (CFLs) is reduction of green house gas emissions. But their significant disadvantage is disposal of spent lamps because of containing a few milligrams of toxic metals, especially mercury and lead. For a successful implementation of any waste management plan, availability of sufficient and accurate information on quantities and compositions of the generated waste and current management conditions is a fundamental prerequisite. In this study, CFLs were selected among 20 different brands in Iran. Content of heavy metals including mercury, lead, nickel, arsenic and chromium was determined by inductive coupled plasma (ICP). Two cities, Tehran and Tabriz, were selected for assessing the current waste management condition of CFLs. The study found that waste generation amount of CFLs in the country was about 159.80, 183.82 and 153.75 million per year in 2010, 2011 and 2012, respectively. Waste generation rate of CFLs in Iran was determined to be 2.05 per person in 2012. The average amount of mercury, lead, nickel, arsenic and chromium was 0.417, 2.33, 0.064, 0.056 and 0.012 mg per lamp, respectively. Currently, waste of CFLs is disposed by municipal waste stream in waste landfills. For improving the current conditions, we propose by considering the successful experience of extended producer responsibility (EPR) in other electronic waste management. The EPR program with advanced recycling fee (ARF) is implemented for collecting and then recycling CFLs. For encouraging consumers to take the spent CFLs back at the end of the products' useful life, a proportion of ARF (for example, 50%) can be refunded. On the other hand, the government and Environmental Protection Agency should support and encourage recycling companies of CFLs both technically and financially in the first place. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Mixed waste treatment with a mediated electrochemical process

    International Nuclear Information System (INIS)

    Hickman, R.G.; Gray, L.W.; Chiba, Z.

    1991-01-01

    The process described in this paper is intended to convert mixed waste containing toxic organic compounds (not heavy metals) to ordinary radioactive waste, which is treatable. The process achieves its goal by oxidizing hydrocarbons to CO 2 and H 2 O. Other atoms that may be present in the toxic organic generally are converted to nonhazardous anions such as sulfate and phosphate. This electro chemical conversion is performed at conditions of temperature and pressure that are just moderately above ambient conditions. Gaseous hydroxides and oxyhydroxides that are formed by many radionuclides during incineration cannot form in this process. 1 ref., 3 figs

  2. Kinetic study of liquid-phase adsorptive removal of heavy metal ions by almond tree (Terminalia catappa L. leaves waste

    Directory of Open Access Journals (Sweden)

    Michael Horsfall Jnr

    2007-04-01

    Full Text Available The kinetic sorption of five metal ions – Al3+, Cr6+, Zn2+, Ag+ and Mn2+- from aqueous solution onto almond tree leaves (ATL waste in single component system has been studied. The experimental data was analyzed in terms of intraparticle diffusion and rate of adsorption, thus comparing transport mechanism and chemical sorption processes. The sorption rates based on the pseudo-second order rate constants for the five metal ions are 0.018 (Al3+, 0.016 (Cr6+, 0.023 (Zn2+, 0.021 (Ag+ and 0.022 (Mn2+ g/mg.min. The adsorption rates are rapid and within 180 min of agitation more than 85 percent of these metal ions has been removed from solution by the ATL waste biomass. The kinetic data suggest that the overall adsorption process is endothermic, and that the rate-limiting step is a surface diffusion controlled process. The results from this study have revealed that the ATL waste, which is hitherto an environmental nuisance, has the ability to adsorb metal ions from solution and the data are relevant for optimal design of wastewater treatment plants. The low cost and easy availability of ATL waste make potential industrial application a strong possibility.

  3. Electrodialytic removal of heavy metals from municipal solid waste incineration fly ash using ammonium citrate as assisting agent

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Ottosen, Lisbeth M.; Villumsen, Arne

    2005-01-01

    Electrodialytic remediation, an electrochemically assisted separation method, has previ-ously shown potential for removal of heavy metals from municipal solid waste incineration (MSWI) fly ashes. In this work electrodialytic remediation of MSWI fly ash using ammonium citrate as assisting agent wa...

  4. Immobilization of metals in contaminated soil from E-waste recycling site by dairy-manure-derived biochar.

    Science.gov (United States)

    Chen, Zhiliang; Zhang, Jianqiang; Liu, Minchao; Wu, Yingxin; Yuan, Zhihui

    2017-08-24

    E-waste is a growing concern around the world and varieties of abandoned E-waste recycling sites, especially in urban area, need to remediate immediately. The impacts of dairy-manure-derived biochars (BCs) on the amelioration of soil properties, the changes in the morphologies as well as the mobility of metals were studied to test their efficacy in immobilization of metals for a potential restoration of vegetation landscape in abandoned E-waste recycling site. The amendment with BCs produced positive effects on bioavailability and mobility reduction for Pb, Cd, Zn and Cu depending on BC ratio and incubation time. The BCs promoted the transformation of species of heavy metals to a more stable fraction, and the metals concentrations in Toxicity Characteristic Leaching Procedure extract declined significantly, especially Pb and Cu. Besides, the BCs ameliorated the substrate with increasing the soil pH, cations exchangeable capacity and available phosphorous, which suggested BC as a potential amendment material for abandoned E-waste recycling sites before restoration of vegetation landscape. Generally, the BC modified by alkaline treatment has a higher efficacy, probably due to increase of specific surface area and porosity as well as the functional groups after alkaline treatment.

  5. Effects of climate change on the toxicity of soils polluted by metal mine wastes to Enchytraeus crypticus

    NARCIS (Netherlands)

    Gonzalez Alcaraz, M.N.; Tsitsiou, E.; Wieldraaijer, R.; Verweij, R.A.; van Gestel, C.A.M.

    2015-01-01

    The present study aimed to assess the effects of climate change on the toxicity of metal-polluted soils. Bioassays with Enchytraeus crypticus were performed in soils polluted by mine wastes (mine tailing, forest, and watercourse) and under different combinations of temperature (20°C and 25°C) and

  6. Electrodialytic removal of heavy metals from municipal solid waste incineration fly ash using ammonium citrate as assisting agent

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Ottosen, Lisbeth M.; Villumsen, Arne

    2005-01-01

    Electrodialytic remediation, an electrochemically assisted separation method, has previ-ously shown potential for removal of heavy metals from municipal solid waste incineration (MSWI) fly ashes. In this work electrodialytic remediation of MSWI fly ash using ammonium citrate as assisting agent...

  7. Leaching characteristics of heavy metals and brominated flame retardants from waste printed circuit boards

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Xiaoyu [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China); Guo, Jie, E-mail: guojie@ecust.edu.cn [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China); Lin, Kuangfei [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China); Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237 (China); Huang, Kai; Deng, Jingjing [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China)

    2013-02-15

    Highlights: ► Cu and Pb were the most leachable heavy metals in WPCBs according to TCLP and SPLP. ► Penta-BDE congeners were dominated in all extracts. ► High dissolved organic matter condition promoted the BFRs leaching rate. ► Leaching from WPCBs was a significant emission source of BFRs in landfill. -- Abstract: Leaching assessment on five heavy metals (copper, zinc, lead, nickel and cadmium) and two brominated flame retardants (BFRs), polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol A (TBBPA), from waste printed circuit boards (WPCBs) were conducted using various leaching methods. The mean leaching concentrations of copper were the highest in both toxicity characteristic leaching procedures (TCLP) and synthetic precipitation leaching procedures (SPLP) tests at 8.6 mg/L and 1.1 mg/L, while only lead (6.2 mg/L) exceeded the TCLP criteria and Chinese EPA regulatory limit (both 5.0 mg/L). However, PBDEs and TBBPA were not detected in TCLP and SPLP tests. Then the BFRs leaching trends and potential leachabilities were further investigated in actual landfill leachates using a modified method. Leaching characteristics that fast-leaching initially followed by slow-desorption over time were generally observed. In landfill leachate tests, the highest leaching concentrations of PBDEs and TBBPA were determined at 30.39 and 12.27 μg/L. Meanwhile, the highest leaching rates were estimated to reach 0.08% and 1.00%, respectively, which were significantly influenced by the dissolved organic carbon contents of extracts, the hydrophobicities of target BFRs and the specific surface areas of WPCBs materials. These results proved that leaching from WPCBs was a significant emission source of BFRs in landfill and electronic waste recycling dumpsite.

  8. Chemical properties of heavy metals in typical hospital waste incinerator ashes in China.

    Science.gov (United States)

    Zhao, Lijuan; Zhang, Fu-Shen; Wang, Kaisheng; Zhu, Jianxin

    2009-03-01

    Incineration has become the main mechanism for hospital waste (HW) disposal in China after the outbreak of Severe Acute Respiratory Syndrome (SARS) in 2003. However, little information is available on the chemical properties of the resulting ashes. In the present study, 22HW ash samples, including 14 samples of bottom ash and eight samples of fly ash, were collected from four typical HW incineration plants located across China. Chemical analysis indicated that the HW ashes contained large amounts of metal salts of Al, Ca, Fe, K, Mg, Na with a concentration range of 1.8-315gkg(-1). Furthermore, the ashes contained high concentrations of heavy metals such as Ag, As, Ba, Bi, Cd, Cr, Cu, Mn, Ni, Pb, Ti, Sb, Sn, Sr, Zn with a vast range of 1.1-121,411mgkg(-1), with higher concentrations found in the fly ash samples. Sequential extraction results showed that Ba, Cr, Ni and Sn are present in the residual fraction, while Cd existed in the exchangeable and carbonate fractions. As, Mn, Zn existed in the Fe-Mn oxide fraction, Pb was present in the Fe-Mn oxide and residual fractions, and Cu was present in the organic matter fraction. Furthermore, toxicity characteristic leaching procedure (TCLP) results indicated that leached amounts of Cd, Cu and Pb from almost all fly ash samples exceeded the USEPA regulated levels. A comparison between the HW ashes and municipal solid waste (MSW) ash showed that both HW bottom ash and fly ash contained higher concentrations of Ag, As, Bi, Cd, Cr, Cu, Pb, Ti, and Zn. This research provides critical information for appropriate HW incineration ash management plans.

  9. The use of waste mussel shells for the adsorption of dyes and heavy metals

    Science.gov (United States)

    Papadimitriou, Chrysi A.; Krey, Grigorios; Stamatis, Nikolaos; Kallaniotis, Argyris

    2016-04-01

    Mussel culture is very important sector of the Greek agricultural economy. The majority of mussel culture activities take place in the area of Central Macedonia, Greece, 60% of total mussel production in Greece producing almost 12 tons of waste mussels shells on a daily basis. Currently there is no legislation concerning the disposal of mussel shells. In the present study the waste shells were used for the removal of dyes and heavy metals from aqueous solutions while powdered mussel shells were added in activated sludge processes for the removal of hexavalent chromium. Mussel shells were cleaned, dried and then crushed in order to form a powder. Powdered mussels shells were used in standard adsorption experiments for the removal of methylene blue and methyl red as well as for the removal of Cr (VI), Cd and Cu. Moreover the powdered mussel shells were added in laboratory scale activated sludge reactors treating synthetic wastewater with hexavalent chromium, in order investigate the effects in activated sludge processes and their potential attribution to the removal of hexavalent chromium. Adsorption experiments indicated almost 100% color removal, while adsorption was directly proportional to the amount of powdered mussel shells added in each case. The isotherms calculated for the case of methylene blue indicated similar adsorption capacity and properties to those of the commercially available activated carbon SAE 2, Norit. High removal efficiencies were observed for the metals, especially in the case of chromium and copper. The addition of powdered mussel shells in the activated sludge processes enhanced the removal of chromium and phosphorus, while enabled the formation of heavier activated sludge flocs and thus enhanced the settling properties of the activated sludge.

  10. Bioaccumulation of heavy metals and two organochlorine pesticides (DDT and BHC) in crops irrigated with secondary treated waste water.

    Science.gov (United States)

    Mishra, Virendra K; Upadhyay, Alka R; Tripathi, B D

    2009-09-01

    Four crop plants Oryza sativa (rice), Solanum melongena (brinjal), Spinacea oleracea (spinach) and Raphanus sativus (radish) were grown to study the impact of secondary treated municipal waste water irrigation. These plants were grown in three plots each of 0.5 ha, and irrigated with secondary treated waste water from a sewage treatment plant. Sludge from the same sewage treatment plant was applied as manure. Cultivated plants were analyzed for accumulation of heavy metals and pesticides. Results revealed the accumulation of six heavy metals cadmium (Cd), chromium (Cr), iron (Fe), copper (Cu), nickel (Ni), and zinc (Zn) as well as two pesticides [1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane; DDT] and benzene hexa chloride (BHC). Order of the plants for the extent of bioaccumulation was S. oleracea > R. sativus > S. melongena > O. sativa. The study has shown the secondary treated waste water can be a source of contamination to the soil and plants.

  11. Heavy metal immobilization and microbial community abundance by vegetable waste and pine cone biochar of agricultural soils.

    Science.gov (United States)

    Igalavithana, Avanthi Deshani; Lee, Sung-Eun; Lee, Young Han; Tsang, Daniel C W; Rinklebe, Jörg; Kwon, Eilhann E; Ok, Yong Sik

    2017-05-01

    In order to determine the efficacy of vegetable waste and pine cone biochar for immobilization of metal/metalloid (lead and arsenic) and abundance of microbial community in different agricultural soils, we applied the biochar produced at two different temperatures to two contaminated soils. Biochar was produced by vegetable waste, pine cone, and their mixture (1:1 ww -1 ) at 200 °C (torrefied biomass) and 500 °C (biochar). Contaminated soils were incubated with 5% (ww -1 ) torrefied biomass or biochar. Sequential extraction, thermodynamic modeling, and scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy were used to evaluate the metal immobilization. Microbial communities were characterized by microbial fatty acid profiles and microbial activity was assessed by dehydrogenase activity. Vegetable waste and the mixture of vegetable waste and pine cone biochar exhibited greater ability for Pb immobilization than pine cone biochar and three torrefied biomass, and vegetable waste biochar was found to be most effective. However, torrefied biomass was most effective in increasing both microbial community and dehydrogenase activity. This study confirms that vegetable waste could be a vital biomass to produce biochar to immobilize Pb, and increase the microbial communities and enzyme activity in soils. Biomass and pyrolytic temperature were not found to be effective in the immobilization of As in this study. Copyright © 2017. Published by Elsevier Ltd.

  12. Investigation of metallic, ceramic, and polymeric materials for engineered barrier applications in nuclear-waste packages

    International Nuclear Information System (INIS)

    Westerman, R.E.

    1980-10-01

    An effort to develop licensable engineered barrier systems for the long-term (about 1000 yr) containment of nuclear wastes under conditions of deep continental geologic disposal has been underway at Pacific Northwest Laboratory since January 1979, under the auspices of the High-Level Waste Immobilization Program. In the present work, the barrier system comprises the hard or structural elements of the package: the canister, the overpack(s), and the hole sleeve. A number of candidate metallic, ceramic, and polymeric materials were put through mechanical, corrosion, and leaching screening tests to determine their potential usefulness in barrier-system applications. Materials demonstrating adequate properties in the screening tests will be subjected to more detailed property tests, and, eventually, cost/benefit analyses, to determine their ultimate applicability to barrier-system design concepts. The following materials were investigated: two titanium alloys of Grade 2 and Grade 12; 300 and 400 series stainless steels, Inconels, Hastelloy C-276, titanium, Zircoloy, copper-nickel alloys and cast irons; total of 14 ceramic materials, including two grades of alumina, plus graphite and basalt; and polymers such as polyamide-imide, polyarylene, polyimide, polyolefin, polyphenylene sulfide, polysulfone, fluoropolymer, epoxy, furan, silicone, and ethylene-propylene terpolymer (EPDM) rubber. The most promising candidates for further study and potential use in engineered barrier systems were found to be rubber, filled polyphenylene sulfide, fluoropolymer, and furan derivatives

  13. Characteristics and evaluation on heavy metal contamination in Changchun municipal waste landfill after closure.

    Science.gov (United States)

    Zhou, Xu-dan; Zhao, Chun-li; Qu, Tong-bao; Wang, Ying; Guo, Tai-jun; Sun, Xiao-gang

    2015-07-01

    In the present study, comprehensive investigation on the spot and typical investigation method were used to assess Mn, Zn, Pb, Cd, Cr, Ni, As and Cu level, pH value, organic matter, total nitrogen and total phosphorus contents in soil of Changchun municipal waste landfill. The results showed that soil in the closure area of Changchun municipal waste landfill was alkaline in nature and the average value of organic matter, total nitrogen and total phosphorus contents were lower than that in normal black soil in Changchun City of Jilin Province. Single factor indices of As, Pb and Cr content was > 1, where P(As) was 1.131, P(Pb) 1.061 and P(Cr) 1.092 mildly contaminated. In different sample spots but the same landfill time, the comprehensive Nemerow contamination indexes of 7a (5 #) and 7a (2 #) were P(2 comprehensive) = 1.176 and P(5 comprehensive) = 1.229. The performance value of of heavy metal contamination in soil was similar and there was a low ecological risk.

  14. Anticipated Degradation Modes of Metallic Engineered Barriers for High-Level Nuclear Waste Repositories

    Science.gov (United States)

    Rodríguez, Martín A.

    2014-03-01

    Metallic engineered barriers must provide a period of absolute containment to high-level radioactive waste in geological repositories. Candidate materials include copper alloys, carbon steels, stainless steels, nickel alloys, and titanium alloys. The national programs of nuclear waste management have to identify and assess the anticipated degradation modes of the selected materials in the corresponding repository environment, which evolves in time. Commonly assessed degradation modes include general corrosion, localized corrosion, stress-corrosion cracking, hydrogen-assisted cracking, and microbiologically influenced corrosion. Laboratory testing and modeling in metallurgical and environmental conditions of similar and higher aggressiveness than those expected in service conditions are used to evaluate the corrosion resistance of the materials. This review focuses on the anticipated degradation modes of the selected or reference materials as corrosion-resistant barriers in nuclear repositories. These degradation modes depend not only on the selected alloy but also on the near-field environment. The evolution of the near-field environment varies for saturated and unsaturated repositories considering backfilled and unbackfilled conditions. In saturated repositories, localized corrosion and stress-corrosion cracking may occur in the initial aerobic stage, while general corrosion and hydrogen-assisted cracking are the main degradation modes in the anaerobic stage. Unsaturated repositories would provide an oxidizing environment during the entire repository lifetime. Microbiologically influenced corrosion may be avoided or minimized by selecting an appropriate backfill material. Radiation effects are negligible provided that a thick-walled container or an inner shielding container is used.

  15. Potential environmental impacts of light-emitting diodes (LEDs): metallic resources, toxicity, and hazardous waste classification.

    Science.gov (United States)

    Lim, Seong-Rin; Kang, Daniel; Ogunseitan, Oladele A; Schoenung, Julie M

    2011-01-01

    Light-emitting diodes (LEDs) are advertised as environmentally friendly because they are energy efficient and mercury-free. This study aimed to determine if LEDs engender other forms of environmental and human health impacts, and to characterize variation across different LEDs based on color and intensity. The objectives are as follows: (i) to use standardized leachability tests to examine whether LEDs are to be categorized as hazardous waste under existing United States federal and California state regulations; and (ii) to use material life cycle impact and hazard assessment methods to evaluate resource depletion and toxicity potentials of LEDs based on their metallic constituents. According to federal standards, LEDs are not hazardous except for low-intensity red LEDs, which leached Pb at levels exceeding regulatory limits (186 mg/L; regulatory limit: 5). However, according to California regulations, excessive levels of copper (up to 3892 mg/kg; limit: 2500), Pb (up to 8103 mg/kg; limit: 1000), nickel (up to 4797 mg/kg; limit: 2000), or silver (up to 721 mg/kg; limit: 500) render all except low-intensity yellow LEDs hazardous. The environmental burden associated with resource depletion potentials derives primarily from gold and silver, whereas the burden from toxicity potentials is associated primarily with arsenic, copper, nickel, lead, iron, and silver. Establishing benchmark levels of these substances can help manufacturers implement design for environment through informed materials substitution, can motivate recyclers and waste management teams to recognize resource value and occupational hazards, and can inform policymakers who establish waste management policies for LEDs.

  16. Atmospheric emissions of typical toxic heavy metals from open burning of municipal solid waste in China

    Science.gov (United States)

    Wang, Yan; Cheng, Ke; Wu, Weidong; Tian, Hezhong; Yi, Peng; Zhi, Guorui; Fan, Jing; Liu, Shuhan

    2017-03-01

    Municipal solid waste (MSW) contains considerable hazardous components and the widely-distributed open MSW burning in heavily-populated urban areas can cause direct exposure of hazardous materials to citizens. By determining the best available representation of composition-varying and time-varying emission factors with fuzzy mathematics method and S-shape curves, a comprehensive atmospheric emission inventories of 9 typical toxic heavy metals (THMs, e.g. mercury (Hg), arsenic (As), lead (Pb), cadmium (Cd), chromium (Cr), selenium (Se), copper (Cu), zinc (Zn), and nickel (Ni)) from open MSW burning activities in China is established during the period of 2000-2013 for the first time. Further, the emissions in 2013 are allocated at a high spatial resolution of 0.5° × 0.5° grid by surrogate indexes. The results show that 9 typical THMs emissions from open MSW burning are estimated at 21.25 t for Hg, 131.52 t for As, 97.12 t for Pb, 10.12 t for Cd, 50.58 t for Cr, 81.95 t for Se, 382.42 t for Cu, 1790.70 t for Zn, and 43.50 t for Ni, respectively. In terms of spatial variation, the majority of emissions are concentrated in relatively developed and densely-populated regions, especially for the eastern, central and southern regions. Moreover, future emissions are also projected for the period of 2015-2030 based on different scenarios of the independent and collaborative effects of control proposals including minimizing waste, improving MSW incineration ratio, and enhancing waste sorting and recycling, etc. The collaborative effect of the above proposals is expected to bring the most effective reduction to THMs emissions from open MSW burning in China except for Hg. The results will be supplementary to all anthropogenic emissions and useful for relevant policy-making and the improvement of urban air quality as well as human health.

  17. 21 CFR 184.1631 - Potassium hydroxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium hydroxide. 184.1631 Section 184.1631 Food... Specific Substances Affirmed as GRAS § 184.1631 Potassium hydroxide. (a) Potassium hydroxide (KOH, CAS Reg... pellets, flakes, sticks, lumps, and powders. Potassium hydroxide is obtained commercially from the...

  18. Hydroxide catalysts for lignin depolymerization

    Energy Technology Data Exchange (ETDEWEB)

    Beckham, Gregg T; Biddy, Mary J.; Kruger, Jacob S.; Chmely, Stephen C.; Sturgeon, Matthew

    2017-10-17

    Solid base catalysts and their use for the base-catalyzed depolymerization (BCD) of lignin to compounds such as aromatics are presented herein. Exemplary catalysts include layered double hydroxides (LDHs) as recyclable, heterogeneous catalysts for BCD of lignin.

  19. Hydroxide catalysts for lignin depolymerization

    Energy Technology Data Exchange (ETDEWEB)

    Beckham, Gregg T.; Biddy, Mary J.; Chmely, Stephen C.; Sturgeon, Matthew

    2017-04-25

    Solid base catalysts and their use for the base-catalyzed depolymerization (BCD) of lignin to compounds such as aromatics are presented herein. Exemplary catalysts include layered double hydroxides (LDHs) as recyclable, heterogeneous catalysts for BCD of lignin.

  20. Relation between leaching characteristics of heavy metals and physical properties of fly ashes from typical municipal solid waste incinerators.

    Science.gov (United States)

    Ni, Peng; Li, Hailong; Zhao, Yongchun; Zhang, Junying; Zheng, Chuguang

    2017-09-01

    Due to the alkalinity and high concentration of potentially hazardous heavy metals, fly ash from a municipal solid waste (MSW) incinerator is classified as hazardous waste, which should be of particular concern. Physical and chemical characterizations of the contrasted fly ashes were investigated to explore the relation between leaching characteristics of heavy metals and physical properties of fly ashes. The results showed that CaClOH, NaCl, Ca(OH) 2 , KCl and SiO 2 were primary mineral compositions in the MSWI fly ashes, and the particle size distribution of fly ash ranged between 10 μm and 300 μm. The smaller the particle size distribution of fly ash, the larger the BET-specific surface area, which was beneficial to the leaching of heavy metals. As a result of various pores, it easily accumulated heavy metals as well. The leaching tests exhibited a high leachability of heavy metals and the leaching concentration of Pb in almost all of the fly ash samples went far beyond the Standard for Pollution Control on the Landfill Site of Municipal Solid Waste. Thereupon, it is necessary to establish proper disposal systems and management strategies for environmental protection based on the characteristics of MSW incineration (MSWI) fly ash in China.

  1. An LCA model for waste incineration enhanced with new technologies for metal recovery and application to the case of Switzerland.

    Science.gov (United States)

    Boesch, Michael E; Vadenbo, Carl; Saner, Dominik; Huter, Christoph; Hellweg, Stefanie

    2014-02-01

    A process model of municipal solid waste incinerators (MSWIs) and new technologies for metal recovery from combustion residues was developed. The environmental impact is modeled as a function of waste composition as well as waste treatment and material recovery technologies. The model includes combustion with a grate incinerator, several flue gas treatment technologies, electricity and steam production from waste heat recovery, metal recovery from slag and fly ash, and landfilling of residues and can be tailored to specific plants and sites (software tools can be downloaded free of charge). Application of the model to Switzerland shows that the treatment of one tonne of municipal solid waste results on average in 425 kg CO2-eq. generated in the incineration process, and 54 kg CO2-eq. accrue in upstream processes such as waste transport and the production of operating materials. Downstream processes, i.e. residue disposal, generates 5 kg CO2-eq. Savings from energy recovery are in the range of 67 to 752 kg CO2-eq. depending on the assumptions regarding the substituted energy production, while the recovery of metals from slag and fly ash currently results in a net saving of approximately 35 kg CO2-eq. A similar impact pattern is observed when assessing the MSWI model for aggregated environmental impacts (ReCiPe) and for non-renewable resource consumption (cumulative exergy demand), except that direct emissions have less and no relevance, respectively, on the total score. The study illustrates that MSWI plants can be an important element of industrial ecology as they provide waste disposal services and can help to close material and energetic cycles. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Leaching for recovery of copper from municipal solid waste incineration fly ash: influence of ash properties and metal speciation.

    Science.gov (United States)

    Lassesson, Henric; Fedje, Karin Karlfeldt; Steenari, Britt-Marie

    2014-08-01

    Recovery of metals occurring in significant amounts in municipal solid waste incineration fly ash, such as copper, could offer several advantages: a decreased amount of potentially mobile metal compounds going to landfill, saving of natural resources and a monetary value. A combination of leaching and solvent extraction may constitute a feasible recovery path for metals from municipal solid waste incineration fly ash. However, it has been shown that the initial dissolution and leaching is a limiting step in such a recovery process. The work described in this article was focused on elucidating physical and chemical differences between two ash samples with the aim of explaining the differences in copper release from these samples in two leaching methods. The results showed that the chemical speciation is an important factor affecting the release of copper. The occurrence of copper as phosphate or silicate will hinder leaching, while sulphate and chloride will facilitate leaching. © The Author(s) 2014.

  3. Plant and fungal biodiversity from metal mine wastes under remediation at Zimapan, Hidalgo, Mexico

    International Nuclear Information System (INIS)

    Ortega-Larrocea, Maria del Pilar; Xoconostle-Cazares, Beatriz; Maldonado-Mendoza, Ignacio E.; Carrillo-Gonzalez, Rogelio; Hernandez-Hernandez, Jani; Garduno, Margarita Diaz; Lopez-Meyer, Melina; Gomez-Flores, Lydia; Gonzalez-Chavez, Ma. del Carmen A.

    2010-01-01

    Plant establishment, presence of arbuscular mycorrhizal fungi (AMF) and other rhizospheric fungi were studied in mine wastes from Zimapan, Hidalgo state, Mexico, using a holistic approach. Two long-term afforested and three non-afforested mine tailings were included in this research. Fifty-six plant species belonging to 29 families were successfully established on the afforested sites, while unmanaged tailings had only a few native plant species colonizing the surrounding soils. Almost all plant roots collected were associated to AMF in these sites. The genus Glomus was the most abundant AMF species found in their rhizosphere; however, the Acaulospora genus was also observed. Other rhizospheric fungi were identified by 18S rDNA sequencing analysis. Their role in these substrates, i.e. biocontrol, pollutant- and organic matter-degradation, and aides that increase plant metal tolerance is discussed. Our results advance the understanding of fungal diversity in sites polluted with metals and present alternative plants for remediation use. - Rhizospheric fungi and organic matter encourage plant vegetation of tailings by pioneers and colonizing species.

  4. Plant and fungal biodiversity from metal mine wastes under remediation at Zimapan, Hidalgo, Mexico.

    Science.gov (United States)

    Ortega-Larrocea, María del Pilar; Xoconostle-Cázares, Beatriz; Maldonado-Mendoza, Ignacio E; Carrillo-González, Rogelio; Hernández-Hernández, Jani; Garduño, Margarita Díaz; López-Meyer, Melina; Gómez-Flores, Lydia; González-Chávez, Ma del Carmen A

    2010-05-01

    Plant establishment, presence of arbuscular mycorrhizal fungi (AMF) and other rhizospheric fungi were studied in mine wastes from Zimapan, Hidalgo state, Mexico, using a holistic approach. Two long-term afforested and three non-afforested mine tailings were included in this research. Fifty-six plant species belonging to 29 families were successfully established on the afforested sites, while unmanaged tailings had only a few native plant species colonizing the surrounding soils. Almost all plant roots collected were associated to AMF in these sites. The genus Glomus was the most abundant AMF species found in their rhizosphere; however, the Acaulospora genus was also observed. Other rhizospheric fungi were identified by 18S rDNA sequencing analysis. Their role in these substrates, i.e. biocontrol, pollutant- and organic matter-degradation, and aides that increase plant metal tolerance is discussed. Our results advance the understanding of fungal diversity in sites polluted with metals and present alternative plants for remediation use. Copyright 2009 Elsevier Ltd. All rights reserved.

  5. Fate of metals and emissions of organic pollutants from torrefaction of waste wood, MSW, and RDF.

    Science.gov (United States)

    Edo, Mar; Skoglund, Nils; Gao, Qiuju; Persson, Per-Erik; Jansson, Stina

    2017-10-01

    Torrefaction of municipal solid waste (MSW), refuse-derived fuel (RDF), and demolition and construction wood (DC) was performed at 220°C and a residence time of 90min in a bench-scale reactor. The levels of toxic polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) contained in emission from the torrefaction process were evaluated. In addition, main ash-forming elements and trace metals in the raw feedstock and char were determined. The use of MSW in fuel blends with DC resulted in lower PCDD and PCDF emissions after torrefaction, compared with the RDF blends. The migration of chlorine from the feedstock to the gas phase reduces the chlorine content of the char which may reduce the risk of alkali chloride-corrosion in char combustion. However, trace metals catalytically active in the formation of PCDD and PCDF remain in the char, thereby may promote PCDD and PCDF formation during subsequent char combustion for energy recovery; this formation is less extensive than when the feedstock is used. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Coffee-Waste Templating of Metal Ion-Substituted Cobalt Oxides for the Oxygen Evolution Reaction.

    Science.gov (United States)

    Yu, Mingquan; Chan, Candace K; Tüysüz, Harun

    2018-02-09

    A facile and scalable method using coffee waste grounds as a hard template has been developed to fabricate nanostructured Co 3 O 4 for the oxygen evolution reaction (OER). Co 3 O 4 incorporating metals with different valences (M/Co=1:4; M=Cu, Ni, Fe, Cr, and W) were also prepared with similar sheet-like structures comprising nanosized crystallites. After detailed characterization by X-ray diffraction, electron microscopy, and nitrogen sorption, the oxides were employed as OER electrocatalysts. Substitution of octahedral and tetrahedral sites of the spinel structure with divalent and trivalent transition metals (Cu, Ni, Fe, and Cr) increased the activity of Co 3 O 4 for the OER, whereas incorporation of hexavalent W led to formation of a second crystal phase and significantly higher electrocatalytic performance. Furthermore, this method is easily scaled up for mass production of Co 3 O 4 with the same nanostructure, which is highly desirable for large-scale application. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Fate of heavy metals during municipal solid waste incineration in Shanghai.

    Science.gov (United States)

    Zhang, Hua; He, Pin-Jing; Shao, Li-Ming

    2008-08-15

    The transfer behavior of heavy metals during municipal solid waste (MSW) incineration was investigated based on 2-year field measurements in two large-scale incinerators in Shanghai. Great temporal and spatial diversification was observed. Most of Hg and Cd were evaporated and then removed by air pollution control (APC) system through condensation and adsorption processes, thus being enriched in the fine APC residues particles. Cr, Cu, and Ni were transferred into the APC residues mainly by entrainment, and distributed uniformly in the two residues flows, as well as in the ash particles with different sizes. Pb and Zn in the APC residues were from both entrainment and evaporation, resulting in the higher concentrations (two to four times) compared with the bottom ash. Arsenic was transported into the flue gas mainly by evaporation, however, its transfer coefficient was lower. Though the heavy metals contents in the APC residues were higher than that in bottom ash, more than 80% of As, Cr, Cu, and Ni, 74-94% of Zn, as well as 46-79% of Pb remained in the bottom ash, due to its high mass ratio (85-93%) in the residues. While 47-73% of Cd and 60-100% of Hg were transferred into the APC residues, respectively.

  8. ACIDIC REMOVAL OF METALS FROM FLUIDIZED CATALYTIC CRACKING CATALYST WASTE ASSISTED BY ELECTROKINETIC TREATMENT

    Directory of Open Access Journals (Sweden)

    R. B. G. Valt

    2015-06-01

    Full Text Available AbstractOne of the main uses of catalysts in the oil industry is in the fluidized catalytic cracking process, which generates large quantities of waste material after use and regeneration cycles and that can be treated by the electrokinetic remediation technique, in which the contaminant metals are transported by migration. In this study, deactivated FCC catalyst was characterized before and after the electrokinetic remediation process to evaluate the amount of metal removed, and assess structural modifications, in order to indicate a possible use as an adsorbent material. The analyses included pH measurement and the concentration profile of vanadium ions along the reactor, X-ray microtomography, X-ray fluorescence, BET analysis and DTA analysis. The results indicated that 40% of the surface area of the material was recovered in relation to the disabled material, showing an increase in the available area for the adsorption. The remediation process removed nearly 31% of the vanadium and 72% of the P2O5 adhering to the surface of the catalyst, without causing structural or thermal stability changes.

  9. Plant and fungal biodiversity from metal mine wastes under remediation at Zimapan, Hidalgo, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ortega-Larrocea, Maria del Pilar [Departamento de Edafologia, Instituto de Geologia, Universidad Nacional Autonoma de Mexico (UNAM) (Mexico); Xoconostle-Cazares, Beatriz [Departamento de Biotecnologia y Bioingenieria, Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional, Av. IPN 2508, Zacatenco 07360, D.F. (Mexico); Maldonado-Mendoza, Ignacio E. [Centro Interdisciplinario de Investigacion para el Desarrollo Integral Regional (CIIDIR)-Instituto Politecnico Nacional - Unidad Sinaloa, Blvd. Juan de Dios Batiz Paredes No. 250, Guasave, Sinaloa 81101 (Mexico); Carrillo-Gonzalez, Rogelio [Programa de Edafologia, Colegio de Postgraduados en Ciencias Agricolas, Campus Montecillo, Carretera Mexico-Texcoco, km 36.5, Texcoco, Estado de Mexico 56230 (Mexico); Hernandez-Hernandez, Jani [Departamento de Edafologia, Instituto de Geologia, Universidad Nacional Autonoma de Mexico (UNAM) (Mexico); Garduno, Margarita Diaz [Universidad Autonoma Chapingo, Carretera Mexico-Texcoco, km 38.5, Chapingo, Estado de Mexico 56230 (Mexico); Lopez-Meyer, Melina [Centro Interdisciplinario de Investigacion para el Desarrollo Integral Regional (CIIDIR)-Instituto Politecnico Nacional - Unidad Sinaloa, Blvd. Juan de Dios Batiz Paredes No. 250, Guasave, Sinaloa 81101 (Mexico); Gomez-Flores, Lydia [Departamento de Biotecnologia y Bioingenieria, Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional, Av. IPN 2508, Zacatenco 07360, D.F. (Mexico); Gonzalez-Chavez, Ma. del Carmen A., E-mail: carmeng@colpos.m [Programa de Edafologia, Colegio de Postgraduados en Ciencias Agricolas, Campus Montecillo, Carretera Mexico-Texcoco, km 36.5, Texcoco, Estado de Mexico 56230 (Mexico)

    2010-05-15

    Plant establishment, presence of arbuscular mycorrhizal fungi (AMF) and other rhizospheric fungi were studied in mine wastes from Zimapan, Hidalgo state, Mexico, using a holistic approach. Two long-term afforested and three non-afforested mine tailings were included in this research. Fifty-six plant species belonging to 29 families were successfully established on the afforested sites, while unmanaged tailings had only a few native plant species colonizing the surrounding soils. Almost all plant roots collected were associated to AMF in these sites. The genus Glomus was the most abundant AMF species found in their rhizosphere; however, the Acaulospora genus was also observed. Other rhizospheric fungi were identified by 18S rDNA sequencing analysis. Their role in these substrates, i.e. biocontrol, pollutant- and organic matter-degradation, and aides that increase plant metal tolerance is discussed. Our results advance the understanding of fungal diversity in sites polluted with metals and present alternative plants for remediation use. - Rhizospheric fungi and organic matter encourage plant vegetation of tailings by pioneers and colonizing species.

  10. Uranium biomineralization by a metal resistant Pseudomonas aeruginosa strain isolated from contaminated mine waste.

    Science.gov (United States)

    Choudhary, Sangeeta; Sar, Pinaki

    2011-02-15

    Uranium biomineralization by a metal-resistant Pseudomonas aeruginosa strain isolated from uranium mine waste was characterized for its potential in bioremediation. Uranium resistance, its cellular localization and chemical nature of uranium-bacteria interaction were elucidated. Survival and uranium biomineralization from mine water were investigated using microcosm experiments. The selected bacterium showed U resistance and accumulation (maximum of 275 mg U g(-1)cell dry wt.) following incubation in 100 mg U L(-1), pH 4.0, for 6 h. Transmission electron microscopy and X-ray diffraction analyses revealed that bioaccumulated uranium was deposited within the cell envelope as needle shaped U-phosphate compounds that attain crystallinity only at pH 4.0. A synergistic involvement of deprotonated phosphate and carboxyl moieties in facilitating bioprecipitation of uranium was evident from FTIR analysis. Based on these findings we attribute the localized U sequestration by this bacterium as innocuous complex to its possible mechanism of uranium resistance. Microcosm data confirmed that the strain can remove soluble uranium (99%) and sequester it as U oxide and phosphate minerals while maintaining its viability. The study showed that indigenous bacteria from contaminated site that can survive uranium and other heavy metal toxicity and sequester soluble uranium as biominerals could play important role in uranium bioremediation. Copyright © 2010 Elsevier B.V. All rights reserved.

  11. Physical and thermal waste utilisation in the nonferrous metal industry; Stoffliche und thermische Abfallverwertung in der Nichteisenmetallindustrie

    Energy Technology Data Exchange (ETDEWEB)

    Sowa, F. [DMT-Gesellschaft fuer Forschung und Pruefung mbH, Essen (Germany)

    1998-09-01

    In its amended form the German Household Waste Technical Code favours physical and thermal utilisation of wastes against dumping. Industrial processes offer various ways of utilising wastes with a high calorific value, e.g. in nonferrous metal production. Besides portraying this branch of industry in Germany the present paper investigates to what extent this topic has already found coverage and what potential it holds for the utilisation of wastes. By way of example it describes a successful demonstration of the physical utilisation of sewage sludge in lead production. [Deutsch] Die Neugestaltung der TA Siedlungsabfall favorisiert die thermische und stoffliche Verwertung von Abfallstoffen gegenueber der Deponierung. Moeglichkeiten fuer die Verwertung heizwertreicher Abfaelle bieten auch industrielle Produktionsprozesse, z.B. auch in der Nichteisenmetallerzeugung. Neben einer Charakterisierung der Branche wird untersucht, inwieweit dieses Thema bereits aufgegriffen worden ist und welches Verwertungspotential zur Verfuegung steht. An einem Beispiel wird die erfolgreiche Demonstration der stofflichen Verwertung von Klaerschlamm in der Bleierzeugung dargestellt. (orig.)

  12. Concentration and transportation of heavy metals in vegetables and risk assessment of human exposure to bioaccessible heavy metals in soil near a waste-incinerator site, South China.

    Science.gov (United States)

    Li, Ning; Kang, Yuan; Pan, Weijian; Zeng, Lixuan; Zhang, Qiuyun; Luo, Jiwen

    2015-07-15

    There is limited study focusing on the bioaccumulation of heavy metals in vegetables and human exposure to bioaccessible heavy metals in soil. In the present study, heavy metal concentrations (Cr, Ni, Cu, Pb and Cd) were measured in five types of vegetables, soil, root, and settled air particle samples from two sites (at a domestic waste incinerator and at 20km away from the incinerator) in Guangzhou, South China. Heavy metal concentrations in soil were greater than those in aerial parts of vegetables and roots, which indicated that vegetables bioaccumulated low amount of heavy metals from soil. The similar pattern of heavy metal (Cr, Cd) was found in the settled air particle samples and aerial parts of vegetables from two sites, which may suggest that foliar uptake may be an important pathway of heavy metal from the environment to vegetables. The highest levels of heavy metals were found in leaf lettuce (125.52μg/g, dry weight) and bitter lettuce (71.2μg/g) for sites A and B, respectively, followed by bitter lettuce and leaf lettuce for sites A and B, respectively. Swamp morning glory accumulated the lowest amount of heavy metals (81.02μg/g for site A and 53.2μg/g for site B) at both sites. The bioaccessibility of heavy metals in soil ranged from Cr (2%) to Cu (71.78%). Risk assessment showed that Cd and Pb in soil samples resulted in the highest non-cancer risk and Cd would result in unacceptable cancer risk for children and risk. The non-dietary intake of soil was the most important exposure pathway, when the bioaccessibility of heavy metals was taken into account. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Combined ultrasonic and bioleaching treatment of hospital waste incinerator bottom ash with simultaneous extraction of selected metals.

    Science.gov (United States)

    Anjum, Fozia; Shahid, Muhammad; Bukhari, ShaziaAnwer; Potgieter, J Herman

    2014-01-01

    The mineralogy, as well as elemental composition, of the incinerated hospital waste (HW) ashes are not well known and need to be investigated for the safe handling and disposal of such ash. A study was conducted to investigate the chemical composition, mineralogy and bioleaching of selected metals from incinerated HW bottom ash using Aspergillus niger under the combined effect ofultrasonic radiation. Different techniques were utilized to determine the elemental composition (Electron Dispersive X-ray Spectroscopy [EDX], atomic absorption spectrophotometry, inductively coupled plasma-optical emission spectroscopy, ultraviolet-visible light spectrophotometer) and mineralogy (X-ray Diffraction) of the raw sample, as well as the bioleached samples. Chemical leaching tests were performed to determine the effect of different organic acids on metals dissolution. Microbes were tested for acid production and leaching capabilities of selected metals from medical waste (MW) bottom ash. Wet chemical and EDX analyses showed that the ash was enriched with metallic elements like Na, K, Ca, Fe and Al with a concentration range of 22-115 (g/kg). Furthermore, the ash contained heavy metals such as Cu, Cr, Ni, Sn and Ti in the range of 0.51-21.74 (mg/kg). Citric and oxalic acids generated by fungi could be important leaching agents acting to dissolve these metals. Under ultrasonic treatment, metals dissolution by the acidic metabolites was at its maximum after just 9 d of leaching. The results showed that the dissolution of metals was much higher in citric and oxalic acid than with other acids. Extraction of metals from incinerated MW ash indicated that this ash may be a potential source of metals in the future.

  14. An LCA model for waste incineration enhanced with new technologies for metal recovery and application to the case of Switzerland

    Energy Technology Data Exchange (ETDEWEB)

    Boesch, Michael E. [Aveny GmbH, Schwandenholzstr. 212, CH-8046 Zürich (Switzerland); Vadenbo, Carl, E-mail: vadenbo@ifu.baug.ethz.ch [ETH Zurich, Institute of Environmental Engineering, Schafmattstrasse 6, CH-8093 Zurich (Switzerland); Saner, Dominik [Swiss Post, Communications, Politics and Social Responsibility, Viktoriastrasse 21, P.O. Box, CH-3030 Berne (Switzerland); Huter, Christoph [City of Zürich, ERZ Entsorgung - Recycling Zürich, Hagenholzstrasse 110, P.O. Box, CH-8050 Zürich (Switzerland); Hellweg, Stefanie [ETH Zurich, Institute of Environmental Engineering, Schafmattstrasse 6, CH-8093 Zurich (Switzerland)

    2014-02-15

    Highlights: • An enhanced process-based LCA model for MSWI is featured and applied in case study. • LCA modeling of recent technological developments for metal recovery from fly ash. • Net release from Swiss MSWI 133 kg CO{sub 2}-eq/tonne waste from attributional LCA perspective. • Net savings from a consequential LCA perspective reach up to 303 kg CO{sub 2}-eq/tonne waste. • Impacts according to ReCiPe and CExD show similar pattern to climate change. - Abstract: A process model of municipal solid waste incinerators (MSWIs) and new technologies for metal recovery from combustion residues was developed. The environmental impact is modeled as a function of waste composition as well as waste treatment and material recovery technologies. The model includes combustion with a grate incinerator, several flue gas treatment technologies, electricity and steam production from waste heat recovery, metal recovery from slag and fly ash, and landfilling of residues and can be tailored to specific plants and sites (software tools can be downloaded free of charge). Application of the model to Switzerland shows that the treatment of one tonne of municipal solid waste results on average in 425 kg CO{sub 2}-eq. generated in the incineration process, and 54 kg CO{sub 2}-eq. accrue in upstream processes such as waste transport and the production of operating materials. Downstream processes, i.e. residue disposal, generates 5 kg CO{sub 2}-eq. Savings from energy recovery are in the range of 67 to 752 kg CO{sub 2}-eq. depending on the assumptions regarding the substituted energy production, while the recovery of metals from slag and fly ash currently results in a net saving of approximately 35 kg CO{sub 2}-eq. A similar impact pattern is observed when assessing the MSWI model for aggregated environmental impacts (ReCiPe) and for non-renewable resource consumption (cumulative exergy demand), except that direct emissions have less and no relevance, respectively, on the total

  15. Impact of metals in surface matrices from formal and informal electronic-waste recycling around Metro Manila, the Philippines, and intra-Asian comparison

    International Nuclear Information System (INIS)

    Fujimori, Takashi; Takigami, Hidetaka; Agusa, Tetsuro; Eguchi, Akifumi; Bekki, Kanae; Yoshida, Aya; Terazono, Atsushi; Ballesteros, Florencio C.

    2012-01-01

    Highlights: ► We quantified 11 metals in surface matrices from e-waste recycling sites at the Philippines. ► Dust had statistical higher levels of metal contamination and health risk compared to soil. ► Formal and informal sites had different metal contaminations. ► Intra-Asian comparison provided common insight on metal contamination from e-waste recycling. - Abstract: We report concentrations, enrichment factors, and hazard indicators of 11 metals (Ag, As, Cd, Co, Cu, Fe, In, Mn, Ni, Pb, and Zn) in soil and dust surface matrices from formal and informal electronic waste (e-waste) recycling sites around Metro Manila, the Philippines, referring to soil guidelines and previous data from various e-waste recycling sites in Asia. Surface dust from e-waste recycling sites had higher levels of metal contamination than surface soil. Comparison of formal and informal e-waste recycling sites (hereafter, “formal” and “informal”) revealed differences in specific contaminants. Formal dust contained a mixture of serious pollutant metals (Ni, Cu, Pb, and Zn) and Cd (polluted modestly), quite high enrichment metals (Ag and In), and crust-derived metals (As, Co, Fe, and Mn). For informal soil, concentration levels of specific metals (Cd, Co, Cu, Mn, Ni, Pb, and Zn) were similar among Asian recycling sites. Formal dust had significantly higher hazardous risk than the other matrices (p < 0.005), excluding informal dust (p = 0.059, almost significant difference). Thus, workers exposed to formal dust should protect themselves from hazardous toxic metals (Pb and Cu). There is also a high health risk for children ingesting surface matrices from informal e-waste recycling sites.

  16. Waste management - sewage - special wastes

    International Nuclear Information System (INIS)

    1987-01-01

    The 27 papers represent a cross-section of the subject waste management. Particular attention is paid to the following themes: waste avoidance, waste product utilization, household wastes, dumping technology, sewage sludge treatments, special wastes, seepage from hazardous waste dumps, radioactive wastes, hospital wastes, purification of flue gas from waste combustion plants, flue gas purification and heavy metals, as well as combined sewage sludge and waste product utilization. The examples given relate to plants in Germany and other European countries. 12 papers have been separately recorded in the data base. (DG) [de

  17. Environmental impacts of unmanaged solid waste at a former base metal mining and ore processing site (Kirki, Greece).

    Science.gov (United States)

    Liakopoulos, Alexandros; Lemière, Bruno; Michael, Konstantinos; Crouzet, Catherine; Laperche, Valérie; Romaidis, Ioannis; Drougas, Iakovos; Lassin, Arnault

    2010-11-01

    The Kirki project aimed to identify, among the mining waste abandoned at a mine and processing plant, the most critical potential pollution sources, the exposed milieus and the main pathways for contamination of a littoral area. This was accompanied by the definition of a monitoring network and remedial options. For this purpose, field analytical methods were extensively used to allow a more precise identification of the source, to draw relevant conceptual models and outline a monitoring network. Data interpretation was based on temporal series and on a geographical model. A classification method for mining waste was established, based on data on pollutant contents and emissions, and their long-term pollution potential. Mining waste present at the Kirki mine and plant sites comprises (A) extraction waste, mainly metal sulfide-rich rocks; (B) processing waste, mainly tailings, with iron and sulfides, sulfates or other species, plus residues of processing reagents; and (C) other waste, comprising leftover processing reagents and Pb-Zn concentrates. Critical toxic species include cadmium and cyanide. The stormy rainfall regime and hilly topography favour the flush release of large amounts of pollutants. The potential impacts and remedial options vary greatly. Type C waste may generate immediate and severe chemical hazards, and should be dealt with urgently by careful removal, as it is localised in a few spots. Type B waste has significant acid mine drainage potential and contains significant amounts of bioavailable heavy metals and metalloids, but they may also be released in solid form into the surface water through dam failure. The most urgent action is thus dams consolidation. Type A waste is by far the most bulky, and it cannot be economically removed. Unfortunately, it is also the most prone to acid mine drainage (seepage pH 1 to 2). This requires neutralisation to prevent acid water accelerating heavy metals and metalloids transfer. All waste management options

  18. The use of a biodegradable chelator for enhanced phytoextraction of heavy metals by Festuca arundinacea from municipal solid waste compost and associated heavy metal leaching.

    Science.gov (United States)

    Zhao, Shulan; Jia, Lina; Duo, Lian

    2013-02-01

    In a column experiment with horizontal permeable barriers, the effects of a biodegradable chelator-nitrilotriacetic acid (NTA) on the uptake of heavy metals from municipal solid waste (MSW) compost by Festuca arundinacea and metal leaching were investigated. The use of NTA was effective in increasing Cu, Pb, and Zn uptakes in shoots of two crops of F. arundinacea. In columns with barriers and treated with 20 mmol NTA per kg MSW compost, metal uptakes by the first and second crop of F. arundinacea were, respectively, 3.8 and 4.0 times for Pb, and 1.8 and 1.7 times for Zn greater with the added NTA than without it. Though NTA application mobilized metals, it caused only slight leaching of metals from MSW compost. Permeable barriers positioned between compost and soil effectively reduced metal leaching. NTA-assisted phytoextraction by turfgrass with permeable barriers to cleanup heavy metal contaminated MSW compost should be environmentally safe. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Tetrabromobisphenol A and heavy metal exposure via dust ingestion in an e-waste recycling region in Southeast China.

    Science.gov (United States)

    Wu, Yuanyuan; Li, Yanyan; Kang, Duan; Wang, Jingjing; Zhang, Yanfang; Du, Dongli; Pan, Bishu; Lin, Zhenkun; Huang, Changjiang; Dong, Qiaoxiang

    2016-01-15

    This study was designed to investigate a prevalent brominated flame retardant tetrabromobisphenol A (TBBPA) and four heavy metals of Pb, Cr, As, Cd in dust samples (52 indoor and 52 outdoor) collected from residential houses in an e-waste recycling area in Southeast China. For TBBPA, the mean concentration in indoor dust (3435 ng/g, dw) was higher than that in outdoor dust (1998 ng/g, dw). For heavy metals, the mean concentrations of Pb, Cr, As, Cd were 399, 151, 48.13, and 5.85 mg/kg in indoor dust, respectively, and were 328, 191, 17.59, and 4.07 mg/kg in outdoor dust, respectively. Except for As, concentrations of TBBPA and other metals decreased with the increased distance away from the e-waste recycling center, suggesting significant contribution of e-waste activities. The daily exposure doses of TBBPA ranged from 0.04 to 7.50 ng/kg-bw/day for adults and from 0.31 to 58.54 ng/kg-bw/day for children, representing the highest values reported to date for TBBPA exposure via dust ingestion. Daily exposure doses of Cr, As, and Cd were all below the reference doses. However, daily exposure dose of Pb for children in areas near the e-waste processing center was above the reference dose, posing significant health concern for children in that region. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Reduction of heavy metals in residues from the dismantling of waste electrical and electronic equipment before incineration.

    Science.gov (United States)

    Long, Yu-Yang; Feng, Yi-Jian; Cai, Si-Shi; Hu, Li-Fang; Shen, Dong-Sheng

    2014-05-15

    Residues disposal from the dismantling of waste electrical and electronic equipment are challenging because of the large waste volumes, degradation-resistance, low density and high heavy metal content. Incineration is advantageous for treating these residues but high heavy metal contents may exist in incinerator input and output streams. We have developed and studied a specialized heavy metal reduction process, which includes sieving and washing for treating residues before incineration. The preferable screen aperture for sieving was found to be 2.36mm (8 meshes) in this study; using this screen aperture resulted in the removal of approximately 47.2% Cu, 65.9% Zn, 26.5% Pb, 55.4% Ni and 58.8% Cd from the residues. Subsequent washing further reduces the heavy metal content in the residues larger than 2.36mm, with preferable conditions being 400rpm rotation speed, 5min washing duration and liquid-to-solid ratio of 25:1. The highest cumulative removal efficiencies of Cu, Zn, Pb, Ni and Cd after sieving and washing reached 81.1%, 61.4%, 75.8%, 97.2% and 72.7%, respectively. The combined sieving and washing process is environmentally friendly, can be used for the removal of heavy metals from the residues and has benefits in terms of heavy metal recycling. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Heavy metal removal and recovery using microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Wilde, E.W. (Westinghouse Savannah River Co., Aiken, SC (United States)); Benemann, J.R. (Benemann (J.R.), Pinole, CA (United States))

    1991-02-01

    Microorganisms -- bacteria, fungi, and microalgae -- can accumulate relatively large amounts of toxic heavy metals and radionuclides from the environment. These organisms often exhibit specificity for particular metals. The metal content of microbial biomass can be a substantial fraction of total dry weight with concentration factors (metal in dry biomass to metal in solution) exceeding one million in some cases. Both living and inert (dead) microbial biomass can be used to reduce heavy metal concentrations in contaminated waters to very low levels -- parts per billion and even lower. In many respects (e.g. specificity, residual metal concentrations, accumulation factors, and economics) microbial bioremoval processes can be superior to conventional processes, such as ion exchange and caustic (lime or hydroxide) precipitation for heavy metals removal from waste and contaminated waters. Thus, bioremoval could be developed to contribute to the clean-up of wastes at the Savannah River Site (SRS) and other DOE facilities. However, the potential advantages of bioremoval processes must still be developed into practical operating systems. A detailed review of the literature suggests that appropriate bioremoval processes could be developed for the SRS. There is great variability from one biomass source to another in bioremoval capabilities. Bioremoval is affected by pH, other ions, temperature, and many other factors. The biological (living vs. dead) and physical (immobilized vs. dispersed) characteristics of the biomass also greatly affect metal binding. Even subtle differences in the microbial biomass, such as the conditions under which it was cultivated, can have major effects on heavy metal binding.

  2. Heavy metal removal and recovery using microorganisms

    International Nuclear Information System (INIS)

    Wilde, E.W.; Benemann, J.R.

    1991-02-01

    Microorganisms -- bacteria, fungi, and microalgae -- can accumulate relatively large amounts of toxic heavy metals and radionuclides from the environment. These organisms often exhibit specificity for particular metals. The metal content of microbial biomass can be a substantial fraction of total dry weight with concentration factors (metal in dry biomass to metal in solution) exceeding one million in some cases. Both living and inert (dead) microbial biomass can be used to reduce heavy metal concentrations in contaminated waters to very low levels -- parts per billion and even lower. In many respects (e.g. specificity, residual metal concentrations, accumulation factors, and economics) microbial bioremoval processes can be superior to conventional processes, such as ion exchange and caustic (lime or hydroxide) precipitation for heavy metals removal from waste and contaminated waters. Thus, bioremoval could be developed to contribute to the clean-up of wastes at the Savannah River Site (SRS) and other DOE facilities. However, the potential advantages of bioremoval processes must still be developed into practical operating systems. A detailed review of the literature suggests that appropriate bioremoval processes could be developed for the SRS. There is great variability from one biomass source to another in bioremoval capabilities. Bioremoval is affected by pH, other ions, temperature, and many other factors. The biological (living vs. dead) and physical (immobilized vs. dispersed) characteristics of the biomass also greatly affect metal binding. Even subtle differences in the microbial biomass, such as the conditions under which it was cultivated, can have major effects on heavy metal binding

  3. A practical approach for solving disposal of rubber waste: Leachability of heavy metals from foamed concrete containing rubber powder waste (RPW)

    Science.gov (United States)

    Kadir, Aeslina Abdul; Hassan, Mohd Ikhmal Haqeem; Sarani, Noor Amira; Yatim, Fatin Syahirah Mohamed; Jaini, Zainorizuan Mohd

    2017-09-01

    Enormous disposal of rubber wastes has become an issue with the facts that all tires have its own life span. Inefficient disposal method of RPW from used tire can cause environmental impact as the heavy metals content in tire can easily leach out thus causing contamination to the soil and waterways. The goals of this study is to identify the heavy metals content of rubber powder waste (RPW) and to determine the potential of leachability of heavy metals from foamed concrete containing different percentages of RPW. Therefore, this study is focused on the leachability of RPW incorporated in foamed concrete. Different percentages of RPW were incorporated in foamed concrete (0%, 6%, 12% and 18%) for the investigation. Leachability tests were done by using toxicity characteristic leaching procedure (TCLP) on crushed samples of foamed concrete incorporated with RPW and were analyzed by using inductive coupled plasma mass spectrometry (ICP-MS). The results from XRF indicated that RPW is high in metals such as Zn, Cu, Ba and Co. The highest concentration of heavy metals in raw RPW is Zn with 51403 ppm which is exceeded USEPA (2010) maximum contaminant level (MCL) of Zn with only 5 ppm. After RPW had been incorporated into a foamed concrete, the results demonstrated that the Zn, Cu, Ba and Co heavy metals were less leached and complied with USEPA standard. The incorporation of RPW into foamed concrete in this study demonstrated that it could be a potential alternative raw material for concrete thus enhancing the possibility of its reuse in safe and sustainable way.

  4. Efficiency Evaluation of Food Waste Materials for the Removal of Metals and Metalloids from Complex Multi-Element Solutions.

    Science.gov (United States)

    Massimi, Lorenzo; Giuliano, Antonella; Astolfi, Maria Luisa; Congedo, Rossana; Masotti, Andrea; Canepari, Silvia

    2018-02-26

    Recent studies have shown the potential of food waste materials as low cost adsorbents for the removal of heavy metals and toxic elements from wastewater. However, the adsorption experiments have been performed in heterogeneous conditions, consequently it is difficult to compare the efficiency of the individual adsorbents. In this study, the adsorption capacities of 12 food waste materials were evaluated by comparing the adsorbents' efficiency for the removal of 23 elements from complex multi-element solutions, maintaining homogeneous experimental conditions. The examined materials resulted to be extremely efficient for the adsorption of many elements from synthetic multi-element solutions as well as from a heavy metal wastewater. The 12 adsorbent surfaces were analyzed by Fourier transform infrared spectroscopy and showed different types and amounts of functional groups, which demonstrated to act as adsorption active sites for various elements. By multivariate statistical computations of the obtained data, the 12 food waste materials were grouped in five clusters characterized by different elements' removal efficiency which resulted to be in correlation with the specific adsorbents' chemical structures. Banana peel, watermelon peel and grape waste resulted the least selective and the most efficient food waste materials for the removal of most of the elements.

  5. Efficiency Evaluation of Food Waste Materials for the Removal of Metals and Metalloids from Complex Multi-Element Solutions

    Directory of Open Access Journals (Sweden)

    Lorenzo Massimi

    2018-02-01

    Full Text Available Recent studies have shown the potential of food waste materials as low cost adsorbents for the removal of heavy metals and toxic elements from wastewater. However, the adsorption experiments have been performed in heterogeneous conditions, consequently it is difficult to compare the efficiency of the individual adsorbents. In this study, the adsorption capacities of 12 food waste materials were evaluated by comparing the adsorbents’ efficiency for the removal of 23 elements from complex multi-element solutions, maintaining homogeneous experimental conditions. The examined materials resulted to be extremely efficient for the adsorption of many elements from synthetic multi-element solutions as well as from a heavy metal wastewater. The 12 adsorbent surfaces were analyzed by Fourier transform infrared spectroscopy and showed different types and amounts of functional groups, which demonstrated to act as adsorption active sites for various elements. By multivariate statistical computations of the obtained data, the 12 food waste materials were grouped in five clusters characterized by different elements’ removal efficiency which resulted to be in correlation with the specific adsorbents’ chemical structures. Banana peel, watermelon peel and grape waste resulted the least selective and the most efficient food waste materials for the removal of most of the elements.

  6. Waste management of printed wiring boards: a life cycle assessment of the metals recycling chain from liberation through refining.

    Science.gov (United States)

    Xue, Mianqiang; Kendall, Alissa; Xu, Zhenming; Schoenung, Julie M

    2015-01-20

    Due to economic and societal reasons, informal activities including open burning, backyard recycling, and landfill are still the prevailing methods used for electronic waste treatment in developing countries. Great efforts have been made, especially in China, to promote formal approaches for electronic waste management by enacting laws, developing green recycling technologies, initiating pilot programs, etc. The formal recycling process can, however, engender environmental impact and resource consumption, although information on the environmental loads and resource consumption is currently limited. To quantitatively assess the environmental impact of the processes in a formal printed wiring board (PWB) recycling chain, life cycle assessment (LCA) was applied to a formal recycling chain that includes the steps from waste liberation through materials refining. The metal leaching in the refining stage was identified as a critical process, posing most of the environmental impact in the recycling chain. Global warming potential was the most significant environmental impact category after normalization and weighting, followed by fossil abiotic depletion potential, and marine aquatic eco-toxicity potential. Scenario modeling results showed that variations in the power source and chemical reagents consumption had the greatest influence on the environmental performance. The environmental impact from transportation used for PWB collection was also evaluated. The results were further compared to conventional primary metals production processes, highlighting the environmental benefit of metal recycling from waste PWBs. Optimizing the collection mode, increasing the precious metals recovery efficiency in the beneficiation stage and decreasing the chemical reagents consumption in the refining stage by effective materials liberation and separation are proposed as potential improvement strategies to make the recycling chain more environmentally friendly. The LCA results provide

  7. Long-Term Experimental Determination of Solubilities of Micro-Crystalline Nd(III) Hydroxide in High Ionic Strength Solutions: Applications to Nuclear Waste Management [A Pitzer Model for Am(III)/Nd(III) hydroxide solubility in NaCl-H2O at 298.15 K to high ionic strengths: Experimental validation and model applications

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Yongliang [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Carlsbad Programs Group; Kirkes, Leslie Dawn [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Carlsbad Programs Group; Marrs, Cassandra [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Carlsbad Programs Group

    2017-12-01

    In this paper, the experimental results from long-term solubility experiments on micro crystalline neodymium hydroxide, Nd(OH)3(micro cr), in high ionic strength solutions at 298.15 K under well-constrained conditions are presented. The starting material was synthesized according to a well-established method in the literature.