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Sample records for hydrochloric acid separating

  1. Hydrochloric acid poisoning

    Science.gov (United States)

    Hydrochloric acid is a clear, poisonous liquid. It is highly corrosive, which means it immediately causes severe damage, such ... poisoning due to swallowing or breathing in hydrochloric acid. This article is for information only. Do NOT ...

  2. Separation of molybdenum(VI) by extraction with n-octylaniline from hydrochloric acid medium

    International Nuclear Information System (INIS)

    Sawant, S.S.; Anuse, M.A.; Chavan, M.B.

    1997-01-01

    N-Octylaniline in benzene was used for the extractive separation of molybdenum(VI) from hydrochloric acid medium. Molybdenum(VI) was extracted quantitatively from 10 ml aqueous solution 1.5M in hydrochloric acid and 10M in lithium chloride into 10 ml of 10% n-octylaniline in benzene. It was stripped from the organic phase with 5% aqueous ammonia solution and estimated spectrophotometrically with thiocyanate at 465 nm. The interference of various ions has been studied in detail and conditions have been established for the determination of molybdenum(VI) in synthetic mixtures and alloy samples. (author)

  3. Danburite decomposition by hydrochloric acid

    International Nuclear Information System (INIS)

    Mamatov, E.D.; Ashurov, N.A.; Mirsaidov, U.

    2011-01-01

    Present article is devoted to decomposition of danburite of Ak-Arkhar Deposit of Tajikistan by hydrochloric acid. The interaction of boron containing ores of Ak-Arkhar Deposit of Tajikistan with mineral acids, including hydrochloric acid was studied. The optimal conditions of extraction of valuable components from danburite composition were determined. The chemical composition of danburite of Ak-Arkhar Deposit was determined as well. The kinetics of decomposition of calcined danburite by hydrochloric acid was studied. The apparent activation energy of the process of danburite decomposition by hydrochloric acid was calculated.

  4. Separation of metal ions by anion exchange in mixtures of hydrochloric acid and hydrofluoric acid

    International Nuclear Information System (INIS)

    Faris, J.P.

    1978-12-01

    Distribution coefficients were determined for the adsorption of more than 40 elements on anion-exchange resins from mixtures of HCl (0.1 to 12M) and HF (0.1-8M). Two resins, Dowex 1 x 10, 200 to 400 mesh and Dowex 1 x 4, 100 to 200 mesh, were used. Distribution coefficients were also determined for the adsorption of many elements on both resins from 0.1 to 12M HCl and 0.1 to 12M HF. Anion exchange in the presence of HF was found useful for separating impurities from various materials for their subsequent determination, and specific procedures used in our spectrochemical laboratory for this purpose are outlined. The results of a literature search on the use of anion exchange in hydrofluoric acid and fluoride-containing media are presented in an extensive bibliography. 404 references, 9 tables

  5. Separation of Rhenium from Lead-Rich Molybdenite Concentrate via Hydrochloric Acid Leaching Followed by Oxidative Roasting

    Directory of Open Access Journals (Sweden)

    Guanghui Li

    2016-11-01

    Full Text Available Lead-rich molybdenite is a typical rhenium-bearing molybdenum resource in China, which has not been efficiently utilized due to its high contents of lead and gangue minerals. In this study, hydrochloric acid was used for preliminarily removing lead and calcite from a lead-rich molybdenite concentrate. Oxidative roasting-ammonia leaching was then carried out for separation of rhenium and extraction of molybdenum. The hydrochloric acid leaching experiments revealed that 93.6% Pb and 97.4% Ca were removed when the leaching was performed at 95 °C for 10 min with HCl concentration of 8 wt. % and liquid-solid ratio of 5 (mL/g. The results of direct oxidative roasting indicated that 89.3% rhenium was volatilized from the raw concentrate after roasting at 600 °C for 120 min in air. In contrast, the rhenium volatilization was enhanced distinctly to 98.0% after the acid-leached concentrate (leaching residue was roasted at 550 °C for 100 min. By the subsequent ammonia leaching, 91.5% molybdenum was leached out from the calcine produced from oxidative roasting of the acid-leached concentrate, while only 79.3% Mo was leached from the calcine produced by roasting molybdenite concentrate without pretreatment.

  6. Hydrochloric acid leach of Agnew Lake uranium concentrate

    International Nuclear Information System (INIS)

    Haque, K.E.; Ipekoglue, B.

    1981-10-01

    Hydrochloric acid leaching was conducted on the radioactive mineral concentrate separated from the Agenw Lake uranium ore. Leach tests conducted at the optimum conditions (75 0 C; 36 hours; 66.0 Kg HCl/tonne; solid:liquid -1:1) resulted in the extraction of 87% uranium and 84% radium. The radionuclide level of the residue was U-0.016%, Th-0.24% and Ra-65 pCi/g solids. However to obtain a residue almost free of radium (i.e., Ra level at the detection limit: 4-6 pCi/g solids), the first stage leach residue was further treated with hydrochloric acid. The radium level in the best second stage leach residue was also above the target level. Therefore, multistage (3 or 4) hydrochloric acid and/or neutral chloride leaching is recommended to obtain tailings almost free of radionuclide

  7. Hydrochloric acid recycling from chlorinated hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Sowieja, D. [Sulzer Escher Wyss GmbH, Ravensburg (Germany); Schaub, M. [Sulzer Chemtech Ltd., Winterthur (Switzerland)

    1993-12-31

    Chlorinated hydrocarbons present a major ecological hazard since most of them are only poorly biodegradable. Incineration is an economical process for their destruction, however the usually recovered sodium or calcium chlorides do not present a value and their disposal may even be very costly. Recovery of hydrochloric acid may therefore present an economical solution, mainly were large quantities of highly chlorinated compounds can be processed (author) 6 refs., 4 figs., 1 tab.

  8. Hydrochloric acid recycling from chlorinated hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Sowieja, D [Sulzer Escher Wyss GmbH, Ravensburg (Germany); Schaub, M [Sulzer Chemtech Ltd., Winterthur (Switzerland)

    1994-12-31

    Chlorinated hydrocarbons present a major ecological hazard since most of them are only poorly biodegradable. Incineration is an economical process for their destruction, however the usually recovered sodium or calcium chlorides do not present a value and their disposal may even be very costly. Recovery of hydrochloric acid may therefore present an economical solution, mainly were large quantities of highly chlorinated compounds can be processed (author) 6 refs., 4 figs., 1 tab.

  9. Leachability of nitrided ilmenite in hydrochloric acid

    OpenAIRE

    Swanepoel, J.J.; van Vuuren, D.S.; Heydenrych, M.

    2011-01-01

    Titanium nitride in upgraded nitrided ilmenite (bulk of iron removed) can selectively be chlorinated to produce titanium tetrachloride. Except for iron, most other components present during this low temperature (ca. 200°C) chlorination reaction will not react with chlorine. It is therefore necessary to remove as much iron as possible from the nitrided ilmenite. Hydrochloric acid leaching is a possible process route to remove metallic iron from nitrided ilmenite without excessive dissolution o...

  10. Separation of carrier-free rhodium isotopes from ruthenium cyclotron targets by the extraction of nitrosylruthenium from hydrochloric acid solution

    International Nuclear Information System (INIS)

    Haasbroek, F.J.; Strelow, F.W.E.; Van der Walt, T.N.

    1981-01-01

    A method is presented for the separation of rhodium isotopes from ruthenium cyclotron targets. After bombardment with deuterons and dissolution of the target material, the ruthenium is converted into a nitrosyl complex by treatment with hydroxylammonium chloride. Aluminium and other elements which have been introduced in the dissolution step, are separated by cation exchange. Ruthenium is then separated by extraction with a mixture of tri-n-butyl phosphate and hexane (4:1), leaving the rhodium in the aqueous phase. No ruthenium is found in the rhodium fraction and the recovery of rhodium is better than 90 per cent [af

  11. Separation of zirconium through extraction in hydrochloric medium with tri-n-octilamine and its spectrophotometric determination with chloroanilic acid

    International Nuclear Information System (INIS)

    Floh, B.; Abrao, A.; Federgruen, L.

    1976-01-01

    A procedure is outlined for the spectrophotometric determination of zirconium using its complex with chloroanilic acid in HC10 4 2M. Interfering elements like Fe, Zn, U, Cy, Cd, Sb, Co, Pb, Hg, Tl, Pt, Au, Pd, Ga, In, Mo and W are previously extracted with tri-n-octylamine 7,5%-benzene from 4 M HCL. Then, the acid content of the solution is ascertained to 10 M HCL and zirconium is extracted with the amine. Nb is a strong interference, being extracted by the amine as well as zirconium and absorbing at the same region as zirconium chloroanilate. Zirconium is stripped from the organic phase with Na 2 CO 3 . The colour development is done with chloroanilic acid in 2 M HC10 4 and the measurements at 340 nm. The method allows the determination of 5 micrograms of Zr. The work curve covers the 0.2 - 2.0 μg Zr/mL range. The procedure is being applied to the determination of zirconium in several alloys and in samples containing zinc, magnesium, iron, aluminium, uranium and thorium [pt

  12. Polarography of niobium in hydrochloric acid

    International Nuclear Information System (INIS)

    Henrion, G.; Adler, F.; Andreas, B.

    1978-01-01

    Dependence between the limiting current and the concentration of niobium and hydrochloric acid has been investigated. With the decrease of niobium concentration the hydrolysis and condensation reactions proceed slower. The time dependence of condensation is shown using ethylene glycol which delays the condensation because of complexation of Nb(5). Hydroxylamine hydrochloride increases the limiting current by a kinetic effect by one order of magnitude which was observed clearly by cyclic voltammetry. Even small amounts of ethylene glycol suppress the kinetic effect. Polarographic determination of niobium in HCl as a supporting electrolyte is possible in concentration above 10 M only. Addition of ethylene glycol and hydroxylamine hydrochloride enables determination of small amounts of niobium in 4 M HCl. (author)

  13. 46 CFR 153.557 - Special requirements for hydrochloric acid.

    Science.gov (United States)

    2010-10-01

    ... CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and... system that carries hydrochloric acid must be lined with: (1) Natural rubber; (2) Neoprene; or (3) A material approved for hydrochloric acid tanks by the Commandant (CG-522). (b) Containment systems for...

  14. Extraction of rare earths and hydrochloric acid by trialkylphosphine oxide

    International Nuclear Information System (INIS)

    Mikhajlichenko, A.I.; Karmannikov, V.P.; Klimenko, M.A.; Fedulova, T.V.

    1983-01-01

    Extraction of rare earth chlorides and hydrochloric acid by trialkylphosphine oxide with different radicals (POR) (RR' 2 PO-POR, where RR'=alkyl of a normal structure, containing 7 to 9 carbon atoms, R=isoamyl) has been studied. Distribution of lanthanum-, neodymium-, lutetium- and yttrium chlorides during extraction with 1.28 mol/l POR solution in white spirit is investigated in the salt concentration range in the equilibrium aqueous phase from 0 to 2.8 mol/l. Lanthanide distribution coefficients increase with an increase in the order number of elements, with the separation coefficients of two extreme members of the series (Lu and La) for chlorides and nitrates constituting 100 and 80, respectively microquantities of Ln against the background of macroquantities of La is 2.6 mol/l. According to the results of measurements of viscosity, electric conductivity and water content in the extracts a conclusion is made on the state of salt in the organic phase. In the systems POR-LnCl 3 -HCl-H 2 O the hydrochloric acid extraction increases with an increase in the rare earth chloride concentration and order number of the element

  15. Use of cationites for separation of transplutonium elements from other elements from aqueous and aqua-alcohol solutions of hydrochloric and nitric acids

    International Nuclear Information System (INIS)

    Guseva, L.I.; Tikhomirova, G.S.

    1984-01-01

    The behaviour of Am, Cm, Pu and certain fragment elements (Cs, Sr, Y, Zr, Nb, Ru, Eu) on cationite dauex-50 in aqueous and aqueous-alcohol solutions of HCl and HNO 3 has been studied. Dependences of distribution coefficients and separation factors of the elements on the acid concentration and alcohol content in the solutions are presented. The sorption of TPE by cationite from HCl and HNO 3 solutions in the presence of alcohol is shown to increase over the range of concentrations studied (from 0.5 mol/L to 4-5 mol/L), which is explained by the salting-out effect of alcohol. The distribution coefficients of TPE in the solutions, containing >= 50% alcohol, constitute >= 10 2 . The distribution coefficients of the fragment elements in the presence of alcohol also increase, but to a considerably lesser extent, which results in a better separation. The study of the washing-out curves has shown that, to separate TPE from fragment elements on cationites, both HCl and HNO 3 solutions can be used, at that, in the case of aqueous solutions a better separation is attained at acid concentration, equal to 1 mol/L, and in the case of eluating by aqueous-alcohol solutions a good separation is achieved at hig-her concentrations of the acids as well

  16. Enhancement of hydrolysis of Chlorella vulgaris by hydrochloric acid.

    Science.gov (United States)

    Park, Charnho; Lee, Ja Hyun; Yang, Xiaoguang; Yoo, Hah Young; Lee, Ju Hun; Lee, Soo Kweon; Kim, Seung Wook

    2016-06-01

    Chlorella vulgaris is considered as one of the potential sources of biomass for bio-based products because it consists of large amounts of carbohydrates. In this study, hydrothermal acid hydrolysis with five different acids (hydrochloric acid, nitric acid, peracetic acid, phosphoric acid, and sulfuric acid) was carried out to produce fermentable sugars (glucose, galactose). The hydrothermal acid hydrolysis by hydrochloric acid showed the highest sugar production. C. vulgaris was hydrolyzed with various concentrations of hydrochloric acid [0.5-10 % (w/w)] and microalgal biomass [20-140 g/L (w/v)] at 121 °C for 20 min. Among the concentrations examined, 2 % hydrochloric acid with 100 g/L biomass yielded the highest conversion of carbohydrates (92.5 %) into reducing sugars. The hydrolysate thus produced from C. vulgaris was fermented using the yeast Brettanomyces custersii H1-603 and obtained bioethanol yield of 0.37 g/g of algal sugars.

  17. Surface roughness of composite resins subjected to hydrochloric acid.

    Science.gov (United States)

    Roque, Ana Carolina Cabral; Bohner, Lauren Oliveira Lima; de Godoi, Ana Paula Terossi; Colucci, Vivian; Corona, Silmara Aparecida Milori; Catirse, Alma Blásida Concepción Elizaur Benitez

    2015-01-01

    The purpose of this study was to determine the influence of hydrochloric acid on surface roughness of composite resins subjected to brushing. Sixty samples measuring 2 mm thick x 6 mm diameter were prepared and used as experimental units. The study presented a 3x2 factorial design, in which the factors were composite resin (n=20), at 3 levels: microhybrid composite (Z100), nanofilled composite (FiltekTM Supreme), nanohybrid composite (Ice), and acid challenge (n=10) at 2 levels: absence and presence. Acid challenge was performed by immersion of specimens in hydrochloric acid (pH 1.2) for 1 min, 4 times per day for 7 days. The specimens not subjected to acid challenge were stored in 15 mL of artificial saliva at 37 oC. Afterwards, all specimens were submitted to abrasive challenge by a brushing cycle performed with a 200 g weight at a speed of 356 rpm, totaling 17.8 cycles. Surface roughness measurements (Ra) were performed and analyzed by ANOVA and Tukey test (p≤0.05). Surface roughness values were higher in the presence (1.07±0.24) as compared with the absence of hydrochloric acid (0.72±0.04). Surface roughness values were higher for microhybrid (1.01±0.27) compared with nanofilled (0.68 ±0.09) and nanohybrid (0.48±0.15) composites when the specimens were not subjects to acid challenge. In the presence of hydrochloric acid, microhybrid (1.26±0.28) and nanofilled (1.18±0,30) composites presents higher surface roughness values compared with nanohybrid (0.77±0.15). The hydrochloric acid affected the surface roughness of composite resin subjected to brushing.

  18. On-line Determination of Hydrochloric Acid in Process Effluent ...

    African Journals Online (AJOL)

    Prof Van Staden

    The sample is sandwiched between two titrants in a holding coil, with the volume of the first base being twice to that of the second one and channeled by flow reversal through a reaction coil to the potentiometric sensor. A linear relationship between peak width and logarithm of the hydrochloric acid concentration was.

  19. Effect of Hydrochloric Acid, Mechanical Scarification, Wet Heat ...

    African Journals Online (AJOL)

    Michael Horsfall

    mechanical scarification and 50% hydrochloric acid were found to induce germination of the ... are mixed with Moringa oloifera leaves to prepare a source and are also ... ability to fix atmospheric nitrogen in soil and the seeds are reported to ...

  20. Decomposition of aluminosilicate ores of Afghanistan by hydrochloric acid

    International Nuclear Information System (INIS)

    Mamatov, E.D.; Khomidi, A.K.

    2015-01-01

    Present article is devoted to decomposition of aluminosilicate ores of Afghanistan by hydrochloric acid. The physicochemical properties of initial aluminosilicate ores were studied by means of X-ray phase, differential-thermal analysis methods. The chemical and mineral composition of aluminosilicate ores was considered. The kinetics of acid decomposition of aluminosilicate ores composed of two stages was studied as well. The flowsheets of complex processing of aluminium comprising ores by means of chloric and acid methods were proposed.

  1. Nontoxic corrosion inhibitors for N80 steel in hydrochloric acid

    OpenAIRE

    M. Yadav; Debasis Behera; Usha Sharma

    2016-01-01

    The purpose of this paper is to evaluate the protective ability of 1-(2-aminoethyl)-2-oleylimidazoline (AEOI) and 1-(2-oleylamidoethyl)-2-oleylimidazoline (OAEOI) as corrosion inhibitors for N80 steel in 15% hydrochloric acid, which may find application as eco-friendly corrosion inhibitors in acidizing processes in petroleum industry. Different concentrations of synthesized inhibitors AEOI and OAEOI were added to the test solution (15% HCl) and the corrosion inhibition of N80 steel in hydroch...

  2. Potential for the use of hydrochloric acid in fission reactor fuel recycle

    International Nuclear Information System (INIS)

    Mailen, J.C.; Bell, J.T.

    1985-01-01

    The chemistry and the effects of the use of hydrochloric acid as the aqueous phase in fuel recycle are surveyed. Available data are sufficient to suggest that separations of actinides and fission products can be at least as good in an HCl-trialkyl amine system as in Purex. Advantages of the HCl system are simpler operations of the off-gas system, better separation of neptunium from uranium and plutonium, better control of oxidation states of the dissolved species, and simpler recycle of the acid. A possible advantage is the more complete dissolution of the fission products, leaving very little insoluble residue. Disadvantages include lack of development of methods for dissolution of oxide fuel in hydrochloric acid, the requirement for processing equipment constructed of titanium, possible complications in the waste-handling system, and the dissolution of much of the cladding in the case of stainless-steel clad fuel

  3. 90Y and 90Sr separation from hydrochloric acid solutions using TODGA as the extractant by solvent extraction and SLM methods

    International Nuclear Information System (INIS)

    Dutta, S.; Raut, D.R.; Mohapatra, P.K.; Manchanda, V.K.

    2010-01-01

    Yttrium-90 is an important radionuclide known for its therapeutic application in nuclear medicine. It is a pure β-emitter with no associated gamma rays and decays to stable daughter 90 Zr. Suitability of this isotope is because of its short half-life (t 1/2 = 64.2 hrs) and high β emissions (E max = 2.28 MeV. An important source of 90 Y is through the decay of 90 Sr, which produces carrier free isotope. 90 Sr (t 1/2 28 yrs) attains secular equilibrium with 90 Y in a short period and can serve as a long term source for the latter isotope because of relatively long half-life of the parent isotope. Solvent extraction studies with N,N,N',N'-tetra-octyldiglycolamide (TODGA) has shown that Y(III) is well extracted in 6 M HCI while at the same time, extraction of Sr(II) is very low leading to a separation factor (D Y /D Sr = 60,000). This property of TODGA can be exploited for the separation of Y from Sr. In the present work, Supported Liquid Membrane (SLM) based separation of Y and Sr has been explored using TODGA as the carrier

  4. 1.7.2. The hydrochloric acid decomposition of pre-baked kaolin clays and siallites

    International Nuclear Information System (INIS)

    Mirsaidov, U.M.; Mirzoev, D.Kh.; Boboev, Kh.E.

    2016-01-01

    Present article of book is devoted to hydrochloric acid decomposition of pre-baked kaolin clays and siallites. The chemical composition of kaolin clays and siallites was determined. The influence of temperature, process duration, acid concentration on hydrochloric acid decomposition of pre-baked kaolin clays and siallites was studied. The optimal conditions of hydrochloric acid decomposition of pre-baked kaolin clays and siallites were determined.

  5. Nontoxic corrosion inhibitors for N80 steel in hydrochloric acid

    Directory of Open Access Journals (Sweden)

    M. Yadav

    2016-11-01

    Full Text Available The purpose of this paper is to evaluate the protective ability of 1-(2-aminoethyl-2-oleylimidazoline (AEOI and 1-(2-oleylamidoethyl-2-oleylimidazoline (OAEOI as corrosion inhibitors for N80 steel in 15% hydrochloric acid, which may find application as eco-friendly corrosion inhibitors in acidizing processes in petroleum industry. Different concentrations of synthesized inhibitors AEOI and OAEOI were added to the test solution (15% HCl and the corrosion inhibition of N80 steel in hydrochloric acid medium containing inhibitors was tested by weight loss, potentiodynamic polarization and AC impedance measurements. Influence of temperature (298–323 K on the inhibition behavior was studied. Surface studies were performed by using FTIR spectra and SEM. Both the inhibitors, AEOI and OAEOI at 150 ppm concentration show maximum efficiency 90.26% and 96.23%, respectively at 298 K in 15% HCl solution. Both the inhibitors act as mixed corrosion inhibitors. The adsorption of the corrosion inhibitors at the surface of N80 steel is the root cause of corrosion inhibition.

  6. Studies on removal of plutonium from oxalic acid containing hydrochloric acid solutions

    Energy Technology Data Exchange (ETDEWEB)

    Ghadse, D R; Noronha, D M; Joshi, A R [Fuel Chemistry Division, Bhabha Atomic Research Centre, Mumbai (India)

    1994-06-01

    Solution containing hydrochloric acid, oxalic acid and considerable quantities of plutonium may be generated while recycling of scrap produced during the metallic fuel fabrication. Plutonium from such waste is normally recovered by anion exchange method after the destruction of oxalic acid using suitable oxidising agent. Solvent extraction and ion exchange methods are being explored in this laboratory for recovery of Pu from oxalic acid containing HCl solutions without prior destruction of oxalic acid. This paper describes the results on the determination of distribution ratios for extraction of Pu(IV) from hydrochloric acid using Aliquot-336 or HDEHP under varying experimental conditions. (author). 5 refs., 5 tabs.

  7. Effect of Hydrochloric Acid Concentration on the Conversion of Sugarcane Bagasse to Levulinic Acid

    Science.gov (United States)

    Anggorowati, Heni; Jamilatun, Siti; Cahyono, Rochim B.; Budiman, Arief

    2018-01-01

    Levulinic acid is a new green platform chemical used to the synthesis of a variety of materials for numerous applications such as fuel additives, polymers and resins. It can be produced using renewable resources such as biomass like sugarcane bagasse which are cheap and widely available as waste in Indonesia. In this study, sugarcane bagasse was hydrolyzed using hydrochloric acid with a solid liquid ratio 1:10. The effects of hydrochloric acid concentration at temperature of 180 °C and reaction time of 30 min were studied. The presence of levulinic acid in product of hydrolysis was measured with gas chromatography (GC). It was found that the highest concentration of levulinic acid was obtained at 1 M hydrochloric acid in 25.56 yield%.

  8. FERMENTABLE SUGARS FROM Lupinus rotundiflorus BIOMASS BY HYDROCHLORIC ACID HYDROLYSIS

    Directory of Open Access Journals (Sweden)

    Mario A. Ruiz-López

    2011-02-01

    Full Text Available It is of general interest to produce fermentable carbohydrates from plant biomass. However, obtaining monosaccharides requires some effort, due to the intricate structure of the cell wall lignocellulosic complex. The aim of this study was to apply a simple two-stage hydrolysis process, using only concentrated hydrochloric acid, to generate fermentable carbohydrates from L. rotundiflorus biomass. First and second stage acid concentrations were 32% and 42.6%. Total monosaccharide yields with respect to dry matter after the first stage, second stage, and the overall process, were 27.5%, 21.0% and 48.4%, respectively. Xylose was the main first stage carbohydrate in the hydrolysate, followed by glucose, arabinose, and galactose. After the second stage only glucose and a small amount of xylose were detected. The polysaccharide hydrolysis was eased by overall low lignin content. Some advantages of this method were the use of a single hydrolyzing agent and that most of the polysaccharides were hydrolyzed in reasonably high yields. The acceptable yield, relative simplicity, the use of most of the biomass along with the wide availability, low cost of the chemicals, and the ample supply of lupines, would facilitate the scaling of these laboratory studies to pilot and industrial levels.

  9. Utilization of hydrochloric acid wastes of titanium-magnesium plants for reprocessing of rare earth mineral raw material

    International Nuclear Information System (INIS)

    Nikonov, V.N.; Troyanker, L.S.; Mikhlin, E.B.

    1979-01-01

    The possibility of using hydrochloric acid wastes of gas purifying plants in rare earth production is studied in laboratory conditions. It is shown that during sorption leaching of a rare earth product using the KU-2X8 cationite instead the reactive hydrochloric acid one may use hydrochloric acid wastes; rare earth element and yttrium extraction in both cases is identical

  10. Hydrochloric acid: an overlooked driver of environmental change.

    Science.gov (United States)

    Evans, Chris D; Monteith, Don T; Fowler, David; Cape, J Neil; Brayshaw, Susan

    2011-03-01

    Research on the ecosystem impacts of acidifying pollutants, and measures to control them, has focused almost exclusively on sulfur (S) and nitrogen (N) compounds. Hydrochloric acid (HCl), although emitted by coal burning, has been overlooked as a driver of ecosystem change because most of it was considered to redeposit close to emission sources rather than in remote natural ecosystems. Despite receiving little regulatory attention, measures to reduce S emissions, and changes in energy supply, have led to a 95% reduction in United Kingdom HCl emissions within 20 years. Long-term precipitation, surface water, and soil solution data suggest that the near-disappearance of HCl from deposition could account for 30-40% of chemical recovery from acidification during this time, affecting both near-source and remote areas. Because HCl is highly mobile in reducing environments, it is a more potent acidifier of wetlands than S or N, and HCl may have been the major driver of past peatland acidification. Reduced HCl loadings could therefore have affected the peatland carbon cycle, contributing to increases in dissolved organic carbon leaching to surface waters. With many regions increasingly reliant on coal for power generation, HCl should be recognized as a potentially significant constituent of resulting emissions, with distinctive ecosystem impacts.

  11. Rare earth elements recycling from waste phosphor by dual hydrochloric acid dissolution

    International Nuclear Information System (INIS)

    Liu, Hu; Zhang, Shengen; Pan, Dean; Tian, Jianjun; Yang, Min; Wu, Maolin; Volinsky, Alex A.

    2014-01-01

    Highlights: • The article provides a new method for recycling rare earth (RE) from waste phosphor. • When compared with the traditional methods, leach rate was much higher. • Y–Eu concentrate and Tb–Ce concentrate were obtained successively. • It would reduce the burden of later extraction, separation and purification. - Abstract: This paper is a comparative study of recycling rare earth elements from waste phosphor, which focuses on the leaching rate and the technical principle. The traditional and dual dissolution by hydrochloric acid (DHA) methods were compared. The method of dual dissolution by hydrochloric acid has been developed. The Red rare earth phosphor (Y 0.95 Eu 0.05 ) 2 O 3 in waste phosphor is dissolved during the first step of acid leaching, while the Green phosphor (Ce 0.67 Tb 0.33 MgAl 11 O 19 ) and the Blue phosphor (Ba 0.9 Eu 0.1 MgAl 10 O 17 ) mixed with caustic soda are obtained by alkali sintering. The excess caustic soda and NaAlO 2 are removed by washing. The insoluble matter is leached by the hydrochloric acid, followed by solvent extraction and precipitation (the DHA method). In comparison, the total leaching rate of the rare earth elements was 94.6% by DHA, which is much higher than 42.08% achieved by the traditional method. The leaching rate of Y, Eu, Ce and Tb reached 94.6%, 99.05%, 71.45%, and 76.22%, respectively. DHA can decrease the consumption of chemicals and energy. The suggested DHA method is feasible for industrial applications

  12. Rare earth elements recycling from waste phosphor by dual hydrochloric acid dissolution

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hu [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Zhang, Shengen, E-mail: zhangshengen@mater.ustb.edu.cn [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Pan, Dean; Tian, Jianjun; Yang, Min; Wu, Maolin [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Volinsky, Alex A. [Department of Mechanical Engineering, University of South Florida, Tampa, FL 33620 (United States)

    2014-05-01

    Highlights: • The article provides a new method for recycling rare earth (RE) from waste phosphor. • When compared with the traditional methods, leach rate was much higher. • Y–Eu concentrate and Tb–Ce concentrate were obtained successively. • It would reduce the burden of later extraction, separation and purification. - Abstract: This paper is a comparative study of recycling rare earth elements from waste phosphor, which focuses on the leaching rate and the technical principle. The traditional and dual dissolution by hydrochloric acid (DHA) methods were compared. The method of dual dissolution by hydrochloric acid has been developed. The Red rare earth phosphor (Y{sub 0.95}Eu{sub 0.05}){sub 2}O{sub 3} in waste phosphor is dissolved during the first step of acid leaching, while the Green phosphor (Ce{sub 0.67}Tb{sub 0.33}MgAl{sub 11}O{sub 19}) and the Blue phosphor (Ba{sub 0.9}Eu{sub 0.1}MgAl{sub 10}O{sub 17}) mixed with caustic soda are obtained by alkali sintering. The excess caustic soda and NaAlO{sub 2} are removed by washing. The insoluble matter is leached by the hydrochloric acid, followed by solvent extraction and precipitation (the DHA method). In comparison, the total leaching rate of the rare earth elements was 94.6% by DHA, which is much higher than 42.08% achieved by the traditional method. The leaching rate of Y, Eu, Ce and Tb reached 94.6%, 99.05%, 71.45%, and 76.22%, respectively. DHA can decrease the consumption of chemicals and energy. The suggested DHA method is feasible for industrial applications.

  13. Decomposition of pre calcined aluminium silicate ores of Afghanistan by hydrochloric acid

    International Nuclear Information System (INIS)

    Khomidi, A.K.; Mamatov, E.D.

    2015-01-01

    Present article is devoted to decomposition of pre calcined aluminium silicate ores of Afghanistan by hydrochloric acid. The physicochemical properties of initial aluminium silicate ores were studied by means of X-ray phase, differential thermal and silicate analysis. The chemical composition of aluminium containing ores was determined. The optimal conditions of interaction of initial and pre calcined siallites with hydrochloric acid were defined. The kinetics of acid decomposition of aluminium silicate ores was studied as well.

  14. Rinsing with antacid suspension reduces hydrochloric acid-induced erosion.

    Science.gov (United States)

    Alves, Maria do Socorro Coelho; Mantilla, Taís Fonseca; Bridi, Enrico Coser; Basting, Roberta Tarkany; França, Fabiana Mantovani Gomes; Amaral, Flávia Lucisano Botelho; Turssi, Cecilia Pedroso

    2016-01-01

    Mouthrinsing with antacids, following erosive episodes, have been suggested as a preventative strategy to minimize tooth surface loss due to their neutralizing effect. The purpose of this in situ study was to evaluate the effect of an antacid suspension containing sodium alginate, sodium bicarbonate and calcium carbonate in controlling simulated erosion of enamel of intrinsic origin. The experimental units were 48 slabs (3×3×2mm) of bovine enamel, randomly divided among 12 volunteers who wore palatal appliances with two enamel slabs. One of them was exposed extra-orally twice a day to 25mL of a hydrochloric acid (HCl) solution (0.01M, pH 2) for 2min. There were two independent phases, lasting 5 days each. In the first phase, according to a random scheme, half of the participants rinsed with 10mL of antacid suspension (Gaviscon(®), Reckitt Benckiser Healthcare Ltd.), while the remainder was rinsed with deionized water, for 1min. For the second phase, new slabs were inserted and participants switched to the treatment not received in the first stage. Therefore, the groups were as follows: (a) erosive challenge with HCl+antacid suspension; (b) erosive challenge with HCl+deionized water (DIW); (c) no erosive challenge+antacid suspension; (d) no erosive challenge+DIW. Specimens were assessed in terms of surface loss using optical profilometry and Knoop microhardness. The data were analyzed using repeated measures two-way analysis of variance and Tukey's tests. Compared to DIW rinses, surface loss of enamel was significantly lower when using an antacid rinse following erosive challenges (p=0.015). The Knoop microhardness of the enamel was significantly higher when the antacid rinse was used (p=0.026). The antacid suspension containing sodium alginate, sodium bicarbonate and calcium carbonate, rinsed after erosive challenges of intrinsic origin, reduced enamel surface loss. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. 1.6. The kinetics of hydrochloric acid decomposition of argillite of Chashma-Sang Deposit

    International Nuclear Information System (INIS)

    Mirsaidov, U.M.; Mirzoev, D.Kh.; Boboev, Kh.E.

    2016-01-01

    Present article of book is devoted to kinetics of hydrochloric acid decomposition of argillite of Chashma-Sang Deposit. It was defined that with temperature increasing the extraction rate of Al_2O_3 and Fe_2O_3 increases. The dependence of extraction rate of Al_2O_3 and Fe_2O_3 on process duration at hydrochloric acid decomposition of argillite was studied. The activation energy of the process was defined.

  16. Dissolution of Platinum in Hydrochloric Acid Under Industrial-Scale Alternating Current Polarization

    Science.gov (United States)

    Myrzabekov, B. E.; Bayeshov, A. B.; Makhanbetov, A. B.; Mishra, B.; Baigenzhenov, O. S.

    2018-02-01

    The electrochemical behavior of platinum in a hydrochloric acid solution under polarization by an industrial-scale alternating current has been investigated. For the electrical dissolution of platinum, titanium is used as an auxiliary electrode, which increases the yield of platinum dissolution by 12.5 pct. The influence of the concentration of hydrochloric acid, the current densities of the platinum and titanium electrodes, and the temperature of the electrolyte on the efficiency of the process of dissolving platinum have all been studied.

  17. 1.7. Acid decomposition of kaolin clays of Ziddi Deposit. 1.7.1. The hydrochloric acid decomposition of kaolin clays and siallites

    International Nuclear Information System (INIS)

    Mirsaidov, U.M.; Mirzoev, D.Kh.; Boboev, Kh.E.

    2016-01-01

    Present article of book is devoted to hydrochloric acid decomposition of kaolin clays and siallites. The chemical composition of kaolin clays and siallites was determined. The influence of temperature, process duration, acid concentration on hydrochloric acid decomposition of kaolin clays and siallites was studied. The optimal conditions of hydrochloric acid decomposition of kaolin clays and siallites were determined.

  18. Determination of uranium isotopes in environmental samples by anion exchange in sulfuric and hydrochloric acid media

    International Nuclear Information System (INIS)

    Popov, L.

    2016-01-01

    Method for determination of uranium isotopes in various environmental samples is presented. The major advantages of the method are the low cost of the analysis, high radiochemical yields and good decontamination factors from the matrix elements, natural and man-made radionuclides. The separation and purification of uranium is attained by adsorption with strong base anion exchange resin in sulfuric and hydrochloric acid media. Uranium is electrodeposited on a stainless steel disk and measured by alpha spectrometry. The analytical method has been applied for the determination of concentrations of uranium isotopes in mineral, spring and tap waters from Bulgaria. The analytical quality was checked by analyzing reference materials. - Highlights: • The method allows cost-effective determination of U isotopes. • High amounts of environmental samples can be analyzed. • High chemical yields, energy resolution and decontamination factors were achieved. • Uranium isotope concentrations in mineral waters from Bulgaria are presented.

  19. Indium sulfide precipitation from hydrochloric acid solutions of calcium and sodium chlorides

    International Nuclear Information System (INIS)

    Kochetkova, N.V.; Bayandina, Yu.E.; Toptygina, G.M.; Shepot'ko, A.O.

    1988-01-01

    The effect of precipitation duration, acid concentration, indium complexing with chloride ions on the process of indium sulfide chemical precipitation in hydrochloric acid solutions, precipitate composition and dispersity are studied. It is established that indium sulfide solubility increases in solutions with acid concentration exceeding 0.40-0.45 mol/l. Calcium and indium chloride addition to diluted hydrochloric solutions greatly increases the solubility of indium sulfide. The effect of calcium chloride on In 2 S 3 solubility is higher than that of sodium chloride

  20. Heavy metal recovery from electric arc furnace steel slag by using hydrochloric acid leaching

    Science.gov (United States)

    Wei, Lim Jin; Haan, Ong Teng; Shean Yaw, Thomas Choong; Chuah Abdullah, Luqman; Razak, Mus'ab Abdul; Cionita, Tezara; Toudehdehghan, Abdolreza

    2018-03-01

    Electric Arc Furnace steel slag (EAFS) is the waste produced in steelmaking industry. Environmental problem such as pollution will occur when dumping the steel slag waste into the landfill. These steel slags have properties that are suitable for various applications such as water treatment and wastewater. The objective of this study is to develop efficient and economical chlorination route for EAFS extraction by using leaching process. Various parameters such as concentration of hydrochloric acid, particle size of steel slag, reaction time and reaction temperature are investigated to determine the optimum conditions. As a result, the dissolution rate can be determined by changing the parameters, such as concentration of hydrochloric acid, particle size of steel slag, reaction time and reaction temperature. The optimum conditions for dissolution rates for the leaching process is at 3.0 M hydrochloric acid, particle size of 1.18 mm, reaction time of 2.5 hour and the temperature of 90°C.

  1. Intramolecular synergistic effect of glutamic acid, cysteine and glycine against copper corrosion in hydrochloric acid solution

    International Nuclear Information System (INIS)

    Zhang Daquan; Xie Bin; Gao Lixin; Cai Qirui; Joo, Hyung Goun; Lee, Kang Yong

    2011-01-01

    The corrosion protection of copper by glutamic acid, cysteine, glycine and their derivative (glutathione) in 0.5 M hydrochloric acid solution has been studied by the electrochemical impedance spectroscopy and cyclic voltammetry. The inhibition efficiency of the organic inhibitors on copper corrosion increases in the order: glutathione > cysteine > cysteine + glutamic acid + glycine > glutamic acid > glycine. Maximum inhibition efficiency for cysteine reaches about 92.9% at 15 mM concentration level. The glutathione can give 96.4% inhibition efficiency at a concentration of 10 mM. The molecular structure parameters were obtained by PM3 (Parametric Method 3) semi-empirical calculation. The intramolecular synergistic effect of glutamic acid, cysteine and glycine moieties in glutathione is attributed to the lower energy of the lowest unoccupied molecular orbital (E LUMO ) level and to the excess hetero-atom adsorption centers and the bigger coverage on the copper surface.

  2. Model Experiment of Thermal Runaway Reactions Using the Aluminum-Hydrochloric Acid Reaction

    Science.gov (United States)

    Kitabayashi, Suguru; Nakano, Masayoshi; Nishikawa, Kazuyuki; Koga, Nobuyoshi

    2016-01-01

    A laboratory exercise for the education of students about thermal runaway reactions based on the reaction between aluminum and hydrochloric acid as a model reaction is proposed. In the introductory part of the exercise, the induction period and subsequent thermal runaway behavior are evaluated via a simple observation of hydrogen gas evolution and…

  3. Corrosion inhibitors for aluminium in hydrochloric acid. Vanilline on aluminium 2S, 57S and 65S

    Energy Technology Data Exchange (ETDEWEB)

    Desai, M.N.

    1972-12-01

    So far, the only aldehyde reported in literature for the inhibition of the corrosion of aluminum in hydrochloric acid, is furfuraldehyde. This study reports vanilline as a corrosion inhibitor for aluminum alloys 2S, 57S, and 65S. These specifications for the alloys are listed. The influence of inhibitor concentration and time on inhibitor efficiency is given in tabular data and illustrated graphically. The corrosion of aluminum alloys 2S, 57S, and 65S increases with time and hydrochloric acid concentration. Polarization measurements indicate that the corrosion of aluminum alloys in hydrochloric acid is cathodically controlled. The behavior of vanilline as a corrosion inhibitor is very interesting. In 2.0N solution of hydrochloric acid, vanilline affords nearly complete protection (97 to 99%) to all the 3 aluminum alloys investigated up to 60 min. However, in 1.0N solutions of hydrochloric acid, the corrosion of aluminum 2S is severely accelerated by vanilline.

  4. Cefuroxime axetil: A commercially available drug as corrosion inhibitor for aluminum in hydrochloric acid solution

    OpenAIRE

    Ameh, Paul O.; Sani, Umar M.

    2016-01-01

    Cefuroxime axetil (CA) a prodrug was tested as corrosion inhibitor for aluminum in hydrochloric acid solution using thermometric, gasometric weight loss and scanning electron microscope (SEM) techniques. Results obtained showed that this compound has a good inhibiting properties for aluminum corrosion in acidic medium, with inhibition efficiencies values reaching 89.87 % at 0.5 g / L . It was also found out that the results from weight loss method are highly consistent with those obtained by ...

  5. Inhibitory effect of some carbazides on corrosion of aluminium in hydrochloric acid and sodium hydroxide solutions

    Energy Technology Data Exchange (ETDEWEB)

    Fouda, A.S. [El-Mansoura Univ. (Egypt). Dept. of Chemistry; Madkour, L.H. [Tanta Univ. (Egypt). Dept. of Chemistry; Elshafei, A.A. [El-Mansoura Univ. (Egypt). Dept. of Chemistry; Elasklany, A.H. [El-Mansoura Univ. (Egypt). Dept. of Chemistry

    1995-06-01

    The dissolution of aluminium in hydrochloric acid and sodium hydroxide solutions in the presence of semicarbazide, thiosemicarbazide and sym.diphenylcarbazide as corrosion inhibitors has been studied using thermometric, weight-loss and polarization methods. The three methods gave consistent results. The higher inhibition efficiency of these compounds in acidic than in alkaline madia may be due to the less negative potential of aluminium in hydrochloric acid solution, favouring adsorption of the additive. The adsorption of these compounds were found to obey Frumkin adsorption isotherm. Cathodic polarization measurements showed that these compounds are cathodic inhibitors and their adsorption in the double layer does not change the mechanism of the hydrogen evolution reaction. The results are analysed in terms of both molecular and cationic adsorption. (orig.)

  6. Investigation of the oxidation states of Pu isotopes in a hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Lee, M.H. [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, P. O. Box 105, Yuseong, Daejeon 305-353 (Korea, Republic of)], E-mail: mhlee@kaeri.re.kr; Kim, J.Y.; Kim, W.H.; Jung, E.C.; Jee, K.Y. [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, P. O. Box 105, Yuseong, Daejeon 305-353 (Korea, Republic of)

    2008-12-15

    The characteristics of the oxidation states of Pu in a hydrochloric acid solution were investigated and the results were applied to a separating of Pu isotopes from IAEA reference soils. The oxidation states of Pu(III) and Pu(IV) were prepared by adding hydroxylamine hydrochloride and sodium nitrite to a Pu stock solution, respectively. Also, the oxidation state of Pu(VI) was adjusted with concentrated HNO{sub 3} and HClO{sub 4}. The stability of the various oxidation states of plutonium in a HCl solution with elapsed time after preparation were found to be in the following order: Pu(III){approx}Pu(VI)>Pu(IV)>Pu(V). The chemical recoveries of Pu(IV) in a 9 M HCl solution with an anion exchange resin were similar to those of Pu(VI). This method for the determination of Pu isotopes with an anion exchange resin in a 9 M HCl medium was applied to IAEA reference soils where the activity concentrations of {sup 239,240}Pu and {sup 238}Pu in IAEA-375 and IAEA-326 were consistent with the reference values reported by the IAEA.

  7. Acid hydrolysis of corn stover using hydrochloric acid: Kinetic modeling and statistical optimization

    Directory of Open Access Journals (Sweden)

    Sun Yong

    2014-01-01

    Full Text Available The hydrolysis of corn stover using hydrochloric acid was studied. The kinetic parameters of the mathematical models for predicting the yields of xylose, glucose, furfural and acetic acid were obtained, and the corresponding xylose generation activation energy of 100 kJ/mol was determined. The characterization of corn stover using with different techniques during hydrolysis indicated an effective removal of xylan and the slightly alteration on the structures of cellulose and lignin. A 23five levels Central Composite Design (CCD was used to develop a statistical model for the optimization of process variables including acid concentration, pretreatment temperature and time. The optimum conditions determined by this model were found to be 108ºC for 80 minutes with acid concentration of 5.8%. Under these conditions, the maximised results are the following: xylose 19.93 g/L, glucose 1.2 g/L, furfural 1.5 g/L, acetic acid 1.3 g/L. The validation of the model indicates a good agreement between the experimental results and the predicted values.

  8. Kinetics of the Leaching Process of an Australian Gibbsitic Bauxite by Hydrochloric Acid

    Directory of Open Access Journals (Sweden)

    Aichun Zhao

    2016-01-01

    Full Text Available Gibbsitic bauxite from Australia was leached by hydrochloric acid in this work. Analysis on kinetics for the extraction of Al2O3 was quantitatively studied. It was concluded that the hydrochloric acid leaching process of gibbsitic bauxite was controlled by chemical reaction. Moreover, the mechanism for the dissolution followed the equation, ln⁡k=39.44-1.66×104(1/T, with an apparent activation energy of 137.90 kJ/mol, according to the equation of k=Ae-Ea/RT. This work aims to provide a good theory support for the process control by using a new method of alumina production from the low grade bauxite.

  9. The extraction of vanadium (IV) from hydrochloric acid solutions by tricaprylmethylammonium chloride and trioctylamine

    International Nuclear Information System (INIS)

    Nakamura, Takato; Sato, Taichi

    1980-01-01

    The extraction of vanadium (IV) from hydrochloric acid solutions by tricaprylmethylammonium chloride (R 3 RNCl, Aliquat-336) and trioctylamine (R 3 N, TOA) in benzene has been investigated under various conditions. In addition, the extraction behaviour of vanadium into the organic phase has been examined by spectrophotometry and electron spin resonance (ESR) spectroscopy. From the distribution data, it is concluded that the extractions of vanadium (IV) from hydrochloric acid solutions by Aliquat-336 and TOA are expressed as VOCl 3 - (aq) + R 3 R'NCl(org) reversible R 3 R'NVOCl 3 (org) + Cl - (aq) and VOCl 2 (aq) + R 3 NHCl(org) reversible R 3 NHVOCl 3 (org) The electronic spectral and ESR results suggest that the complexes, R 3 R'NVOCl 3 and R 3 NH.VOCl 3 , formed in the organic phase are not always stable, but easily hydrolized or oxidized. (author)

  10. Electrochemical studies of novel corrosion inhibitor for mild steel in 1 M hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Ahmed A. Al-Amiery

    2018-06-01

    Full Text Available The electrochemical performance of a novel organic corrosion inhibitor 6-(4-hydroxyphenyl-3-mercapto-7,8-dihydro-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine [HT3], for mild steel in 1 M hydrochloric acid is evaluated by potentiodynamic curves. The experimental results show that the investigated inhibitor [HT3], which can effectively retard the corrosion process that occurs to mild steel with a hydrochloric acid solution by providing a protective coating for the mild steel that, can be weakened by increasing the temperature. Furthermore, the inhibition efficiency of [HT3] increased with increasing the concentrations of the inhibitors and decreased with increasing temperature. Keywords: Corrosion, Inhibitor, Mild steel, Potentiodynamic polarization, HT3, NMR, FT-IR

  11. Interaction of Benzimidazoles and Benzotriazole: Its Corrosion Protection Properties on Mild Steel in Hydrochloric Acid

    Science.gov (United States)

    Ramya, K.; Mohan, Revathi; Joseph, Abraham

    2014-11-01

    Synergistic hydrogen-bonded interaction of alkyl benzimidazoles and 1,2,3-benzotrizole and its corrosion protection properties on mild steel in hydrochloric acid at different temperatures have been studied using polarization, EIS, adsorption, surface studies, and computational methods. The extent of synergistic interaction increases with temperature. Quantum chemical approach is used to calculate some electronic properties of the molecules and to ascertain the synergistic interaction, inhibitive effect, and molecular structures. The corrosion inhibition efficiencies and the global chemical reactivity relate to some parameters, such as total energy, E HOMO, E LUMO, and gap energy (Δ E). 1,2,3-Benzotrizole interacts with benzimidazoles derivatives up to a bond length of approximately 1.99 Å. This interaction represents the formation of a hydrogen bond between the 1,2,3-benzotrizole and benzimidazoles. This synergistic interaction of 1,2,3-benzotrizole and benzimidazole derivatives offers extended inhibition efficiency toward mild steel in hydrochloric acid.

  12. Extraction of copper zinc and iron from hydrochloric acid solutions by means of different extractants

    Energy Technology Data Exchange (ETDEWEB)

    Zhivkova, Svetlana [Institute of Chemical Engineering - Bulgarian Academy of Sciences, Sofia (Bulgaria)

    2011-07-01

    The extraction of copper, zinc and iron from hydrochloric acid solutions has been studied. The experiments have been carried out using various solvents, involving different extraction mechanisms – solvating, anion-exchange, cation-exchange, bifunctional . Mixtures of these extractants have been also used. The extraction properties of these extractant mixtures toward copper, zinc and iron, the effect of used modifiers and diluents have been also investigated. Key words: Copper, Zinc, Iron, Extraction, Extractant, Modifier, Diluent.

  13. Corrosion Inhibition of Mild Steel in Hydrochloric Acid by Sodium Lauryl Sulfate (SLS

    Directory of Open Access Journals (Sweden)

    Atul Kumar

    2008-01-01

    Full Text Available Effect of Sodium Lauryl Sulfate (SLS, a surfactant on corrosion of mild steel in 1 M hydrochloric acid was studied using three techniques namely: weight loss, electrochemical polarization and metallurgical research microscopy. Results obtained reveal that SLS is good inhibitor and shows very good corrosion inhibition efficiency (IE. The IE was found to vary with concentration of inhibitor and temperature. The electrochemical polarization result revealed that SLS is anodic in nature.

  14. Corrosion Inhibition of Mild Steel in Hydrochloric Acid by Sodium Lauryl Sulfate (SLS)

    OpenAIRE

    Atul Kumar

    2008-01-01

    Effect of Sodium Lauryl Sulfate (SLS), a surfactant on corrosion of mild steel in 1 M hydrochloric acid was studied using three techniques namely: weight loss, electrochemical polarization and metallurgical research microscopy. Results obtained reveal that SLS is good inhibitor and shows very good corrosion inhibition efficiency (IE). The IE was found to vary with concentration of inhibitor and temperature. The electrochemical polarization result revealed that SLS is anodic in nature.

  15. Inhibition of the corrosion of mild steel in hydrochloric acid by isatin ...

    African Journals Online (AJOL)

    The inhibition of corrosion of mild steel in hydrochloric acid by isatin glycine (ING) and isatin (IN) at 30-60 oC and concentrations of 0.0001 M to 0.0005 M was studied via weight loss method. At the highest inhibitor concentration studied ING exhibited inhibition efficiency of 87% while IN exhibited 84% at 60 oC. A chemical ...

  16. Selective liquid-liquid extraction of antimony(III from hydrochloric acid media by N-n-octylaniline in xylene

    Directory of Open Access Journals (Sweden)

    M. A. ANUSE

    2004-04-01

    Full Text Available N-n-Octylaniline in xylene was used for the extraction separation of antimony(III from hydrochloric acid media. Antimony(III was extracted quantitatively with 10 mL 4 % N-n-octylaniline in xylene. It was stripped from the organic phase with 0.5 M ammonia and estimated photometrically by the iodide method. The effect of metal ion, acid, reagent concentration and various foreign ions was investigated. The method affords binary and ternary separation of antimony(III from tellurium(IV, selenium(IV, lead(II, bismuth(III, tin(IV, germanium(IV, copper(II, gold(III, iron(III and zinc(II. The method is applicable for the analysis of synthetic mixtures, alloys and semiconductor thin films. It is fast, accurate and precise.

  17. Separation of rare earths from solutions of phosphoric acid

    International Nuclear Information System (INIS)

    Jones, E.A.

    1977-01-01

    Rare earths are separated from 6M phosphoric acid by adsorption onto cation resin BIORAD AG50W-X8. The phosphoric acid is then washed from the column, and the rare earths are eluted with 4M hydrochloric acid

  18. Investigating the Acid Failure of Aluminium Alloy in 2 M Hydrochloric Acid Using Vernonia amygdalina

    Directory of Open Access Journals (Sweden)

    Olugbenga A. Omotosho

    2012-04-01

    Full Text Available The acid failure of aluminium alloy in 2 M hydrochloric acid solution in the presence of Vernonia amygdalina extract was investigated using gasometric technique. Aluminium alloy coupons of dimension 4 cm by 1 cm were immersed in test solutions of free acid and also those containing extract volumes of 2, 3, 4 and 5 cm3 at ambient temperature for 30 minutes. The volumes of hydrogen gas evolved as a result of the rate of reaction were recorded and analyzed. Analysis revealed that maximum inhibitor efficiency which corresponds to the lowest corrosion rate was obtained at optimum inhibitor volumes of 5 cm3, with reduction in the corrosion rate observed to follow in order of increasing extract volumes. Adsorption study revealed that Temkin isotherm best described the metal surface interaction with the extract phytochemicals, with 12 minutes becoming the best exposure time for the phytochemicals to adsorb to the metal surface at all volumes. Statistical modelling of the corrosion rate yielded an important relationship suitable for estimating corrosion rate values once volumes of the extract is known. Microstructural studies, showed an indirect relationship between crack growth rates and extract volumes, while consistency of the irregular intermetallic phases increases with increasing extract volumes.

  19. Inhibitive Effect of Butyltin Trichloride on Dissolution and Localized Corrosion of Aluminium in Sodium Hydroxide and Hydrochloric Acid

    OpenAIRE

    Mourad, M.Y.; Ibrahim, E.H.; Seliman, S.A.

    1990-01-01

    The dissolution of aluminium in sodium hydroxide and hydrochloric acid in the presence of butyltin trichloride as corrosion inhibitor has been studied by hydrogen evolution and thermometric methods. Experimental findings indicate that the inhibition effect of butyltin trichloride takes place through an adsorption mechanism following the Frumkin's isotherm. Butyltin trichloride acts as a weakly adsorbed inhibitor in NaOH and as a strongly adsorbed inhibitor in hydrochloric acid medium. Wile...

  20. Extraction of magnesium from calcined dolomite ore using hydrochloric acid leaching

    Science.gov (United States)

    Royani, Ahmad; Sulistiyono, Eko; Prasetiyo, Agus Budi; Subagja, Rudi

    2018-05-01

    Magnesium is widely used in varieties industrial sector. Dolomite is one source of magnesium besides seawater. The extraction of magnesium from dolomite ores can be done by leaching process. In this work, the dolomite leaching to extract magnesium by hydrochloric acid was investigated. The leaching experiments were performed in a spherical glass batch reactor having a capacity of 1000 ml. The effects of the stirring speed, acid concentration, reaction temperature and liquid-solid ratio for each reaction time of 1; 2; and 3 h on the Mg leaching have been evaluated. 5 ml of solution sample were collected from the leached solutions, then it was filtered prior to analysis by ICP OES. The experimental results show that the magnesium extraction increases along with the increase of acid concentration, liquid-solid ratio and temperature. The optimum conditions for magnesium extraction were achieved at temperature 75 °C, extraction time 3 h, the HCl concentration of 2 M, the liquid-solid ratio 20 ml/g and stirring speed of 400 rpm. At this condition 98, 82 % of magnesium were extracted from dolomite. The conclusion obtained from this leaching process is that the magnesium can be extracted from dolomite by using hydrochloric acid solutions.

  1. Ginger extract as green corrosion inhibitor of mild steel in hydrochloric acid solution

    Science.gov (United States)

    Fidrusli, A.; Suryanto; Mahmood, M.

    2018-01-01

    Ginger extract as corrosion inhibitor from natural resources was studied to prevent corrosion of mild steel in acid media. Ginger rhizome was extracted to produce green corrosion inhibitor (G-1) while ginger powder bought at supermarket was also extract to form green corrosion inhibitor (G-2). Effectiveness of inhibitor in preventing corrosion process of mild steel was studied in 1.0 M of hydrochloric acid. The experiment of weight loss method and polarization technique were conducted to measure corrosion rate and inhibition efficiency of mild steel in solution containing 1.0 M of hydrochloric acid with various concentration of inhibitor at room temperature. The results showed that, the rate of corrosion dropped from 8.09 mmpy in solution containing no inhibitor to 0.72 mmpy in solution containing 150g/l inhibitor while inhibition efficiency up to 91% was obtained. The polarization curve in polarization experiments shows that the inhibition efficiency is 86% with high concentration of inhibitor. The adsorption of ginger extract on the surface of mild steel was observed by using optical microscope and the characterization analysis was done by using pH measurement method. When high concentration of green inhibitor in the acid solution is used, the pH at the surface of steel is increasing.

  2. Effect of beverages on bovine dental enamel subjected to erosive challenge with hydrochloric acid.

    Science.gov (United States)

    Amoras, Dinah Ribeiro; Corona, Silmara Aparecida Milori; Rodrigues, Antonio Luiz; Serra, Mônica Campos

    2012-01-01

    This study evaluated by an in vitro model the effect of beverages on dental enamel previously subjected to erosive challenge with hydrochloric acid. The factor under study was the type of beverage, in five levels: Sprite® Zero Low-calorie Soda Lime (positive control), Parmalat® ultra high temperature (UHT) milk, Ades® Original soymilk, Leão® Ice Tea Zero ready-to-drink low-calorie peach-flavored black teaand Prata® natural mineral water (negative control). Seventy-five bovine enamel specimens were distributed among the five types of beverages (n=15), according to a randomized complete block design. For the formation of erosive wear lesions, the specimens were immersed in 10 mL aqueous solution of hydrochloric acid 0.01 M for 2 min. Subsequently, the specimens were immersed in 20 mL of the beverages for 1 min, twice daily for 2 days at room temperature. In between, the specimens were kept in 20 mL of artificial saliva at 37ºC. The response variable was the quantitative enamel microhardness. ANOVA and Tukey's test showed highly significant differences (penamel exposed to hydrochloric acid and beverages. The soft drink caused a significantly higher decrease in microhardness compared with the other beverages. The black tea caused a significantly higher reduction in microhardness than the mineral water, UHT milk and soymilk, but lower than the soft drink. Among the analyzed beverages, the soft drink and the black tea caused the most deleterious effects on dental enamel microhardness.

  3. Solvent Extraction of Tungsten(VI) from Moderate Hydrochloric Acid Solutions with LIX 63

    Energy Technology Data Exchange (ETDEWEB)

    Truong, Hoai Thanh; Lee, Man Seung [Mokpo National University, Jeollanamdo (Korea, Republic of); Kim, Yong Hwan [Incheon Technology Service Centre, Incheon (Korea, Republic of)

    2017-06-15

    The solvent extraction of tungsten(VI) from hydrochloric acid solutions using 5,8-diethyl-7-hydroxydodecan-6-one oxime (LIX 63) was analyzed in solutions having an initial pH range from 2 to 5, by varying the concentration of metal and extractant. In our experimental range, the cationic exchange reaction as well as the solvation reaction occurred simultaneously. The cation exchange reaction was identified by applying a slope analysis method to the extraction data. The existence of cationic tungsten(VI) species was confirmed by ion exchange experiments with Diphonix resin at pH 3. Further study is needed to identify the nature of this tungsten cationic species.

  4. Investigation of copper(I sulphide leaching in oxidative hydrochloric acid solution

    Directory of Open Access Journals (Sweden)

    Branislav Marković

    2015-12-01

    Full Text Available Present work is focused on the copper (I sulphide leaching with sodium chloride in hydrochloric acid solution and with introduction of gaseous oxygen. Chemical reactions of leaching and their thermodynamic probabilities are predicted based on the literature data and products which were formed during the process and the overall leaching reaction was defined. The influence of temperature and time on the leaching degree of copper was experimentally determined. The quantity of dissolved copper increases with the increase of both investigated parameters. Elemental sulphur was formed as the main leaching product, precipitated at the particle surfaces and chloride ions have a role to disrupt the creation of this passive layer.

  5. Kinetic Aspects of Leaching Zinc from Waste Galvanizing Zinc by Using Hydrochloric Acid Solutions

    Science.gov (United States)

    Sminčáková, Emília; Trpčevská, Jarmila; Pirošková, Jana

    2017-10-01

    In this work, the results of acid leaching of flux skimmings coming from two plants are presented. Sample A contained two phases, Zn(OH)Cl and NH4Cl. In sample B, the presence of three phases, Zn5(OH)8Cl2·H2O, (NH4)2(ZnCl4) and ZnCl2(NH3)2, was proved. The aqueous solution of hydrochloric acid and distilled water was used as the leaching medium. The effects of the leaching time, temperature and concentration of the leaching medium on the zinc extraction were investigated. The apparent activation energy, E a = 4.61 kJ mol-1, and apparent reaction order n = 0.18 for sample A, and the values E a = 6.28 kJ mol-1 and n = 0.33 for sample B were experimentally determined. Zinc leaching in acid medium is a diffusion-controlled process.

  6. Pretreatment of corn stover for sugar production using dilute hydrochloric acid followed by lime.

    Science.gov (United States)

    Zu, Shuai; Li, Wen-zhi; Zhang, Mingjian; Li, Zihong; Wang, Ziyu; Jameel, Hasan; Chang, Hou-min

    2014-01-01

    In this study, a two stage process was evaluated to increase the sugar recovery. Firstly, corn stover was treated with diluted hydrochloric acid to maximize the xylose yield, and then the residue was treated with lime to alter the lignin structure and swell the cellulose surface. The optimal condition was 120 °C and 40 min for diluted hydrochloric acid pretreatment followed by lime pretreatment at 60 °C for 12h with lime loading at 0.1 g/g of substrate. The glucose and xylose yield was 78.0% and 97.0%, respectively, with cellulase dosage at 5 FPU/g of substrate. The total glucose yield increased to 85.9% when the cellulase loading was increased to 10 FPU/g of substrate. This two stage process was effective due to the swelling of the internal surface, an increase in the porosity and a decrease in the degree of polymerization. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Hydrochloric acid leaching of uranium, thorium, radium and rare-earth elements, from an Elliot lake radioactive ore

    International Nuclear Information System (INIS)

    Mahdy, M.A.

    1988-01-01

    Extraction of uranium by commercial methods using sulphuric acid developed a lot of environmental problems. To avoid such problems, other uranium extraction techniques have been adopted including fluorination, chlorination, chlorine assisted leaching, hydrochloric acid leaching, etc. This work is oriented towards the study of the factors controlling the hydrochloric acid leaching. The target of the study is to extract the total amount of U, Th, Ra-226 and rare earth elements. By using a suitable combination of the leaching factors, it was possible to achieve the designed target

  8. The Comparison of Hydrochloric Acid and Phosphoric Acid Treatments in the Preparation of Montmorillonite Catalysts for RNA Synthesis

    Science.gov (United States)

    Aldersley, Michael Frank; Joshi, Prakash C.; Huang, Yixing

    2017-09-01

    The treatment of clay minerals with a preliminary acid wash and titration to pH 7 has proven to generate catalysts for the most interesting of oligomerization reactions in which activated RNA-nucleotides generate oligomers up to 40-mers. Significantly, not all clay minerals become catalytic following this treatment and none are catalytic in the absence of such treatment. The washing procedure has been modified and explored further using phosphoric acid and the outcomes are compared to those obtained when clay samples are prepared following a hydrochloric acid wash.

  9. The Comparison of Hydrochloric Acid and Phosphoric Acid Treatments in the Preparation of Montmorillonite Catalysts for RNA Synthesis.

    Science.gov (United States)

    Aldersley, Michael Frank; Joshi, Prakash C; Huang, Yixing

    2017-09-01

    The treatment of clay minerals with a preliminary acid wash and titration to pH 7 has proven to generate catalysts for the most interesting of oligomerization reactions in which activated RNA-nucleotides generate oligomers up to 40-mers. Significantly, not all clay minerals become catalytic following this treatment and none are catalytic in the absence of such treatment. The washing procedure has been modified and explored further using phosphoric acid and the outcomes are compared to those obtained when clay samples are prepared following a hydrochloric acid wash.

  10. The criteria of critical runaway and stable temperatures of catalytic decomposition of hydrogen peroxide in the presence of hydrochloric acid

    International Nuclear Information System (INIS)

    Lu, K.-T.; Yang, C.-C.; Lin, P.-C.

    2006-01-01

    The hydrogen peroxide and hydrochloric acid are used in close proximity in the computer chip manufacture. The hydrochloric acid catalyzes an exothermic decomposition of hydrogen peroxide into oxygen and water. The accumulation of heat and non-condensable gas increases temperature and pressure in this reaction process always lead to runaway reaction and accident owing to inadvertent mixing. Thus, the chemical reaction hazard has to be clearly identified. Its critical runaway temperatures and unstable reaction criteria in this reaction process have to be determined urgently. In this investigation, we estimated its kinetic parameters at various volumetric ratios of the hydrogen peroxide to hydrochloric acid. Then, used these kinetic parameters to evaluate their critical temperatures and stable criteria in each reaction processes. The analytic results are important and useful for the design of safety system in the computer chip manufacture

  11. Kinetics of Ni3S2 sulfide dissolution in solutions of sulfuric and hydrochloric acids

    Science.gov (United States)

    Palant, A. A.; Bryukvin, V. A.; Vinetskaya, T. N.; Makarenkova, T. A.

    2008-02-01

    The kinetics of Ni3S2 sulfide (heazlewoodite) dissolution in solutions of hydrochloric and sulfuric acids is studied. The process under study in the temperature range of 30 90°C is found to occur in a kinetic regime and is controlled by the corresponding chemical reactions of the Ni3S2 decomposition by solutions of inorganic acids ( E a = 67 92 kJ/mol, or 16 22 kcal/mol). The only exception is the Ni3S2-HCl system at elevated temperatures (60 90°C). In this case, the apparent activation energy decreases sharply to 8.8 kJ/mol (2.1 kcal/mol), which is explained by the catalytic effect of gaseous chlorine formed under these conditions. The studies performed are related to the physicochemical substantiation of the hydrometallurgical processing of the copper-nickel converter mattes produced in the industrial cycle of the Norilsk Mining Company.

  12. Comparison of sulfuric and hydrochloric acids as catalysts in hydrolysis of Kappaphycus alvarezii (cottonii).

    Science.gov (United States)

    Meinita, Maria Dyah Nur; Hong, Yong-Ki; Jeong, Gwi-Taek

    2012-01-01

    In this study, hydrolysis of marine algal biomass Kappaphhycus alvarezii using two different acid catalysts was examined with the goal of identifying optimal reaction conditions for the formation of sugars and by-products. K. alvarezii were hydrolyzed by autoclave using sulfuric acid or hydrochloric acid as catalyst with different acid concentrations (0.1-1.0 M), substrate concentrations (1.0-13.5%), hydrolysis time (10-90 min) and hydrolysis temperatures (100-130 (°)C). A difference in galactose, glucose, reducing sugar and total sugar content was observed under the different hydrolysis conditions. Different by-product compounds such as 5-hydroxymethylfurfural and levulinic acid were also observed under the different reaction conditions. The optimal conditions for hydrolysis were achieved at a sulfuric acid concentration, temperature and reaction time of 0.2 M, 130 °C and 15 min, respectively. These results may provide useful information for the development of more efficient systems for biofuel production from marine biomass.

  13. Ruthenium (4) and ruthenium (3) state in hydrochloric acid solutions under microwave irradiation

    International Nuclear Information System (INIS)

    Bashilov, A.V.; Kuz'min, N.M.; Nesterov, A.A.; Runov, V.K.

    2000-01-01

    Reactions of hydration, poly- and depolymerization, oxidation-reduction processes with ruthenium (4) and ruthenium (3) participation are investigated in hydrochloric acid solutions under microwave irradiation by the methods of molecular absorption spectroscopy in UV visible region taking K 4 [Ru 2 OCl 10 ] as an example. Content of state forms of ruthenium (4) and ruthenium (3), absorption characteristics of forming complexes are calculated. Variation of microwave irradiation parameters and HCl concentration permits to prepare solutions containing [RuCl 6 ] 2+ (95 %) and [(RuOH) 2 (H 2 O) 6 (OH) 2 ] 4+ (98 %) preeminently predominant forms. The role of microwave effect directly is established taking as an example the process of ruthenium (4) hydration [ru

  14. The role of octanol in the extraction of hydrochloric acid by trilaurylamine dissolved in benzene

    International Nuclear Information System (INIS)

    Muhammed, M.A.

    1976-01-01

    The extraction of hydrochloric acid by trilaurylamine (TLA) dissolved in benzene was studied in the presence and in absence of n-octanol. The extraction of HCl was found to be enhanced by the addition of octanol to the organic phase. In order to explain this effect by means of the law of mass action, the systems TLA-HCl-benzene and n-octanol-HCl-benzene as well as TLA-octanol-benzene were also studied. It was found that TLA reacts with octanol to form a complex TLAROH, while the octanol itself associates in benzene to form dimers and tetramers, although it does not extract HCl alone from the dilute solutions used in the present study. The enhancement of the extraction of HCl by TLA upon the addition of n-octanol could be described by the formation of the species TLA.ROH.HCl and its stability constant was determined. (author)

  15. CORROSION INHIBITIVE PROPERTIES OF EXTRACT OF JATROPHA CURCAS LEAVES ON MILD STEEL IN HYDROCHLORIC ACID ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    J. Odusote

    2016-09-01

    Full Text Available Jatropha curcas leaves extract was tested as a green corrosion inhibitor for mild steel in aqueous hydrochloric acid solution using gravimetric and thermometric techniques. The results reveal that the inhibition efficiency vary with concentration of the leaf extract and the time of immersion. Maximum inhibition efficiency was found to be 95.92% in 2M HCl with 0.5 g/l concentration of the extract in gravimetric method, while 87.04% was obtained in thermometric method. The inhibiting effect was attributed to the presence of alkaloids, flavonoids, saponins, tannins and phenol in the extract. The adsorption processes of the Jatropha curcas leaves extract onto the mild steel is consistent with the assumptions of Langmuir isotherm model and also found to be spontaneous. From the results, a physical adsorption mechanism is proposed for the adsorption of Jatropha curcas leaves extract onto mild steel surface.

  16. Benzaldehyde, 2-hydroxybenzoyl hydrazone derivatives as inhibitors of the corrosion of aluminium in hydrochloric acid.

    Science.gov (United States)

    Fouda, A S; Gouda, M M; El-Rahman, S I

    2000-05-01

    The effect of benzaldehyde, 2-hydroxybenzoyl hydrazone derivatives on the corrosion of aluminium in hydrochloric acid has been investigated using thermometric and polarization techniques. The inhibitive efficiency ranking of these compounds from both techniques was found to be: 2>3>1>4. The inhibitors acted as mixed-type inhibitors but the cathode is more polarized. The relative inhibitive efficiency of these compounds has been explained on the basis of structure of the inhibitors and their mode of interaction at the surface. Results show that these additives are adsorbed on an aluminium surface according to the Langmuir isotherm. Polarization measurements indicated that the rate of corrosion of aluminium rapidly increases with temperature over the range 30-55 degrees C both in the absence and in the presence of inhibitors. Some thermodynamic data of the adsorption process are calculated and discussed.

  17. The Inhibitive Action Of Sodium Soya Sulphonate Towards The Corrosion Of Aluminium In Hydrochloric Acid

    OpenAIRE

    Mourad, M. Y.; Mead, A. I.; Seliman, S. A.

    1993-01-01

    The dissolution of aluminium in 2M hydrochloric acid in the presence of sodium soya sulphonate (SSS) as corrosion inhibitor has been studied using hydrogen evolution and thermometric methods. The two methods gave consistent results. The results obtained indicate that the inhibitive effect of the sulphonated mixture relates to chemisorption mechanism on the metal surface via the n electrons in the double bonds. تمت دراسة ذوبان الألمونيوم في محلول 2 مولارى من حمض الهيدروكلوريك في وجود سلفونا...

  18. Leaching of Titanium and Silicon from Low-Grade Titanium Slag Using Hydrochloric Acid Leaching

    Science.gov (United States)

    Zhao, Longsheng; Wang, Lina; Qi, Tao; Chen, Desheng; Zhao, Hongxin; Liu, Yahui; Wang, Weijing

    2018-05-01

    Acid-leaching behaviors of the titanium slag obtained by selective reduction of vanadium-bearing titanomagnetite concentrates were investigated. It was found that the optimal leaching of titanium and silicon were 0.7% and 1.5%, respectively. The titanium and silicon in the titanium slag were firstly dissolved in the acidic solution to form TiO2+ and silica sol, and then rapidly reprecipitated, forming hydrochloric acid (HCl) leach residue. Most of the silicon presented in the HCl leach residue as floccules-like silica gel, while most of the titanium was distributed in the nano-sized rod-like clusters with crystallite refinement and intracrystalline defects, and, as such, 94.3% of the silicon was leached from the HCl leach residue by alkaline desilication, and 96.5% of the titanium in the titanium-rich material with some rutile structure was then digested by the concentrated sulfuric acid. This provides an alternative route for the comprehensive utilization of titanium and silicon in titanium slag.

  19. Quantitative Leaching of a Spent Cell Phone Printed Circuit Board by Hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Alafara A. Baba

    2014-07-01

    Full Text Available This paper presents a kinetic data on the hydrometallurgical recovery of some metal ions from a printed circuit board (PCB of a spent cell phone by hydrochloric acid leaching. The effects of acid concentration, temperature and particle diameter on the dissolution efficiency at various leaching time intervals were examined. The results of the leaching investigations showed that the powdered cell phone dissolution increases with increasing acid concentration, system temperature with decreasing particle diameter at 360 rpm. With 2M HCl solution, about 88.49% of the sample was dissolved within 120 minutes using 0.075-0.112 mm particle diameter at 800 C. The results of the study indicated that the dissolution reaction could be represented by a shrinking core model with surface chemical reaction. A value of 0.61, 60.67 kJ/mol and 12.9s-1 were calculated as reaction order, activation energy and frequency factor, respectively for the dissolution process.

  20. Study and characterization of powder mackerel (Scomberomorus commerson) bone gelatin through hydrolysis of hydrochloric acid

    Science.gov (United States)

    Mardawati, E.; Sugandi, H.; Kayaputri, I. L.; Cahyana, Y.; Wira, D. W.; Pujianto, T.; Kastaman, R.

    2018-02-01

    Gelatin is one of the most common food additives in the food and beverage industry. Gelatin is generally made of leather or pig bones, causing concerns about the halal and safety of its product. Mackerel fish bone (Scomberomorus commerson) is a waste fish that has not been utilized well and it contains 18.6% of collagen so that it can be made into gelatin. The purpose of this research is to know the relation between HCl concentration with physical and chemical characteristics of gelatin and to know the best HCl concentration for gelatin production. Based on the physical and chemical analysis of gelatin, it is known that the concentration of hydrochloric acid influences the yield, viscosity, gel strength and pH produced. The higher HCl concentration there will be decrease in the pH value, gel strength, viscosity and protein. The yield will rise to the optimum point then decrease with respect to the high HCl concentration. Gelatin with 2% HCl concentration was the best treatment, with pH value 3.83, viscosity 3.65cP, gel strength 190.50 blooms which fulfilled British Standard, yield 10.16%, protein content 43.34%. It has functional group such as amino acids glycine, proline and hydroxyproline and 15 other amino acids, the gelatin group uptake in the region of amide wave numbers A, amides I, II and III, with a gelatin molecular weight of 290.35 g/mol.

  1. Controlled-potential coulometric determination of plutonium with a hydrochloric acid-sulfamic acid electrolyte and phosphate complexing

    International Nuclear Information System (INIS)

    Jackson, D.D.; Hollen, R.M.; Roensch, F.R.; Rein, J.E.

    1981-01-01

    Total plutonium is selectively determined by a controlled-potential coulometric method in which plutonium is reduced to Pu(III) at 0.25 V (vs. SCE) in a 5.5 M hydrochloric acid-0.015 M sulfamic acid electrolyte, diverse ions are oxidized at 0.57 V, phosphate is added to reduce the Pu(III)-Pu(IV) potential, and Pu(III) is oxidized to Pu(IV) at 0.68 V. None of more than 50 metal ions present in nuclear fuel-cycle material interferes. Many anions are without effect and most interfering ones are removed by preliminary fuming with perchloric acid. The apparatus described consists mainly of commercial components. The relative standard deviation is < 0.1% at the 5-mg plutonium level

  2. Surface chemical compositions and dispersity of starch nanocrystals formed by sulfuric and hydrochloric acid hydrolysis.

    Science.gov (United States)

    Wei, Benxi; Xu, Xueming; Jin, Zhengyu; Tian, Yaoqi

    2014-01-01

    Surface chemical compositions of starch nanocrystals (SNC) prepared using sulfuric acid (H2SO4) and hydrochloric acid (HCl) hydrolysis were analyzed by X-ray photoelectron spectroscopy (XPS) and FT-IR. The results showed that carboxyl groups and sulfate esters were presented in SNC after hydrolysis with H2SO4, while no sulfate esters were detected in SNC during HCl-hydrolysis. TEM results showed that, compared to H2SO4-hydrolyzed sample, a wider size distribution of SNC prepared by HCl-hydrolysis were observed. Zeta-potentials were -23.1 and -5.02 mV for H2SO4- and HCl-hydrolyzed SNC suspensions at pH 6.5, respectively. Nevertheless, the zeta-potential values decreased to -32.3 and -10.2 mV as the dispersion pH was adjusted to 10.6. After placed 48 h at pH 10.6, zeta-potential increased to -24.1 mV for H2SO4-hydrolyzed SNC, while no change was detected for HCl-hydrolyzed one. The higher zeta-potential and relative small particle distribution of SNC caused more stable suspensions compared to HCl-hydrolyzed sample.

  3. Surface chemical compositions and dispersity of starch nanocrystals formed by sulfuric and hydrochloric acid hydrolysis.

    Directory of Open Access Journals (Sweden)

    Benxi Wei

    Full Text Available Surface chemical compositions of starch nanocrystals (SNC prepared using sulfuric acid (H2SO4 and hydrochloric acid (HCl hydrolysis were analyzed by X-ray photoelectron spectroscopy (XPS and FT-IR. The results showed that carboxyl groups and sulfate esters were presented in SNC after hydrolysis with H2SO4, while no sulfate esters were detected in SNC during HCl-hydrolysis. TEM results showed that, compared to H2SO4-hydrolyzed sample, a wider size distribution of SNC prepared by HCl-hydrolysis were observed. Zeta-potentials were -23.1 and -5.02 mV for H2SO4- and HCl-hydrolyzed SNC suspensions at pH 6.5, respectively. Nevertheless, the zeta-potential values decreased to -32.3 and -10.2 mV as the dispersion pH was adjusted to 10.6. After placed 48 h at pH 10.6, zeta-potential increased to -24.1 mV for H2SO4-hydrolyzed SNC, while no change was detected for HCl-hydrolyzed one. The higher zeta-potential and relative small particle distribution of SNC caused more stable suspensions compared to HCl-hydrolyzed sample.

  4. Sodium phthalamates as corrosion inhibitors for carbon steel in aqueous hydrochloric acid solution

    International Nuclear Information System (INIS)

    Flores, Eugenio A.; Olivares, Octavio; Likhanova, Natalya V.; Dominguez-Aguilar, Marco A.; Nava, Noel; Guzman-Lucero, Diego; Corrales, Monica

    2011-01-01

    Highlights: → N-Alkyl-sodium phthalamates as corrosion inhibitors for industry in acidic medium. → Compounds behaved as mixed type inhibitors and followed Langmuir adsorption isotherm. → Efficiencies were proportional to aliphatic chain length and inhibitor concentration. → Iron complexes and chelates with phthalamates contributed to carbon steel protection. - Abstract: Three compounds of N-alkyl-sodium phthalamates were synthesized and tested as corrosion inhibitors for carbon steel in 0.5 M aqueous hydrochloric acid. Tests showed that inhibitor efficiencies were related to aliphatic chain length and dependent on concentration. N-1-n-tetradecyl-sodium phthalamate displayed moderate efficiency against uniform corrosion, 42-86% at 25 deg. C and 25-60% at 40 o C. Tests indicated that compounds behave as mixed type inhibitors where molecular adsorption on steel followed Langmuir isotherm, whereas thermodynamic suggested that a physisorption process occurred. XPS analysis confirmed film formation on surface, where Fe +2 complexes and Fe +2 chelates with phthalamates prevented steel from further corrosion.

  5. Highly improved synthesis of gold nanobipyramids by tuning the concentration of hydrochloric acid

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Ying; Zhu, Jian; Li, Jianjun; Zhao, Junwu, E-mail: nanoptzhao@163.com [Xi’an Jiaotong University, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology (China)

    2016-07-15

    Fabrication of gold nanobipyramids (Au BPs) has attracted great attention because they exhibit more advantageous plasmonic properties. In this study, Au BPs were synthesized by the well-known seeded growth in the presence of hydrochloric acid (HCl). The effects of the ingredients, including HCl, silver nitrate (AgNO{sub 3}), l-Ascorbic acid (AA), and seeds on the structure and yield of the Au BPs were systemically investigated. The results showed that the abundant HCl could improve the yield of Au BPs and decrease the longitudinal surface plasmon resonance wavelength. Under the circumstance of higher concentration of AA and AgNO{sub 3}, more byproducts were resulted. In addition, the effect of HCl under different ratios of seed solution to AA has also been studied. The results showed that the yield was less sensitive to HCl when the amount of seed solution was small. If substantial AA was added to the system, then abundant HCl should be introduced correspondingly to improve the yield of Au BPs.

  6. A simple procedure for preparing chitin oligomers through acetone precipitation after hydrolysis in concentrated hydrochloric acid.

    Science.gov (United States)

    Kazami, Nao; Sakaguchi, Masayoshi; Mizutani, Daisuke; Masuda, Tatsuhiko; Wakita, Satoshi; Oyama, Fumitaka; Kawakita, Masao; Sugahara, Yasusato

    2015-11-05

    Chitin oligomers are of interest because of their numerous biologically relevant properties. To prepare chitin oligomers containing 4-6 GlcNAc units [(GlcNAc)4-6], α- and β-chitin were hydrolyzed with concentrated hydrochloric acid at 40 °C. The reactant was mixed with acetone to recover the acetone-insoluble material, and (GlcNAc)4-6 was efficiently recovered after subsequent water extraction. Composition analysis using gel permeation chromatography and MALDI-TOF mass spectrometry indicated that (GlcNAc)4-6 could be isolated from the acetone-insoluble material with recoveries of approximately 17% and 21% from the starting α-chitin and β-chitin, respectively. The acetone precipitation method is highly useful for recovering chitin oligomers from the acid hydrolysate of chitin. The changes in the molecular size and higher-order structure of chitin during the course of hydrolysis were also analyzed, and a model that explains the process of oligomer accumulation is proposed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Furfuryl alcohol as corrosion inhibitor for N80 steel in hydrochloric acid

    International Nuclear Information System (INIS)

    Vishwanatham, S.; Haldar, N.

    2008-01-01

    The ability of furfuryl alcohol (FA) as corrosion inhibitor in controlling corrosion of N80 steel in 15% hydrochloric acid has been investigated. It is found that the percentage inhibition of FA increases almost linearly with its concentration (in the range 10 mM-80 mM) and attains about 91% at 80 mM. FA shows significant inhibition at higher temperatures also (∼82% at 60 deg. C;∼74% at 110 deg. C with 80 mM concentration). FA undergoes acid catalyzed polymerization under the experimental conditions to give polyfurfuryl alcohols (PFA) as evidenced by FTIR and NMR spectral data. Thermodynamic parameters for the corrosion of steel in presence and absence of the inhibitor have been calculated. The inhibitive action may be attributed to adsorption of inhibitor molecules on the active sites of the metal surface following Temkin adsorption isotherm. Potentiodynamic polarization curves indicate that FA acts as mixed type inhibitor. A plausible mechanism for the mode of inhibition has been proposed

  8. Surface Chemical Compositions and Dispersity of Starch Nanocrystals Formed by Sulfuric and Hydrochloric Acid Hydrolysis

    Science.gov (United States)

    Wei, Benxi; Xu, Xueming; Jin, Zhengyu; Tian, Yaoqi

    2014-01-01

    Surface chemical compositions of starch nanocrystals (SNC) prepared using sulfuric acid (H2SO4) and hydrochloric acid (HCl) hydrolysis were analyzed by X-ray photoelectron spectroscopy (XPS) and FT-IR. The results showed that carboxyl groups and sulfate esters were presented in SNC after hydrolysis with H2SO4, while no sulfate esters were detected in SNC during HCl-hydrolysis. TEM results showed that, compared to H2SO4-hydrolyzed sample, a wider size distribution of SNC prepared by HCl-hydrolysis were observed. Zeta-potentials were −23.1 and −5.02 mV for H2SO4- and HCl-hydrolyzed SNC suspensions at pH 6.5, respectively. Nevertheless, the zeta-potential values decreased to −32.3 and −10.2 mV as the dispersion pH was adjusted to 10.6. After placed 48 h at pH 10.6, zeta-potential increased to −24.1 mV for H2SO4-hydrolyzed SNC, while no change was detected for HCl-hydrolyzed one. The higher zeta-potential and relative small particle distribution of SNC caused more stable suspensions compared to HCl-hydrolyzed sample. PMID:24586246

  9. Study on tea leaves extract as green corrosion inhibitor of mild steel in hydrochloric acid solution

    Science.gov (United States)

    Hamdan, A. B.; Suryanto; Haider, F. I.

    2018-01-01

    Corrosion inhibitor from extraction of plant has been considered as the most preferable and most chosen technique to prevent corrosion of metal in acidic medium because of the environmental friendly factor. In this study, black tea leaves extraction was tested as corrosion inhibitor for mild steel in 0.1M of hydrochloric acid (HCl) with the absence and presence of corrosion inhibitor. The efficiency and effectiveness of black tea as corrosion inhibitor was tested by using corrosion weight loss measurement experiment was carried out with varies parameters which with different concentration of black tea extract solution. The extraction of black tea solution was done by using aqueous solvent method. The FT-IR result shows that black tea extract containing compounds such as catechin, caffeine and tannins that act as anti-corrosive reagents and responsible to enhance the effectiveness of black tea extract as corrosion inhibitor by forming the hydrophobic thin film through absorption process. As a result of weight loss measurement, it shows that loss in weight of mild steel reduces as the concentration of inhibitor increases. The surface analysis was done on the mild steel samples by using SEM.

  10. Impact of α-amylase combined with hydrochloric acid hydrolysis on structure and digestion of waxy rice starch.

    Science.gov (United States)

    Li, Hongyan; Zhu, Yanqiao; Jiao, Aiquan; Zhao, Jianwei; Chen, Xiaoming; Wei, Benxi; Hu, Xiuting; Wu, Chunsen; Jin, Zhengyu; Tian, Yaoqi

    2013-04-01

    The structure and in vitro digestibility of native waxy rice starch by the combined hydrolysis of α-amylase and hydrochloric acid were investigated in this study. The combined hydrolysis technique generated higher hydrolysis rate and extent than the enzymatic hydrolysis. The granular appearance and chromatograph profile demonstrated that α-amylase and hydrochloric acid exhibited different patterns of hydrolysis. The rise in the ratio of absorbance 1047/1022cm(-1), the melting temperature range (Tc-To), and the melting enthalpy (ΔH) were observed during the combined hydrolysis. These results suggest that α-amylase simultaneously cleaves the amorphous and crystalline regions, whereas the amorphous regions of starch granules are preferentially hydrolyzed during the acid hydrolysis. Furthermore, the combined hydrolysis increased rapidly digestible starch (RDS) while decreased slowly digestible starch (SDS) and resistant starch (RS), indicating that the hydrolysis mode affected the digestion property of native waxy rice starch. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Removing hydrochloric acid exhaust products from high performance solid rocket propellant using aluminum-lithium alloy.

    Science.gov (United States)

    Terry, Brandon C; Sippel, Travis R; Pfeil, Mark A; Gunduz, I Emre; Son, Steven F

    2016-11-05

    Hydrochloric acid (HCl) pollution from perchlorate based propellants is well known for both launch site contamination, as well as the possible ozone layer depletion effects. Past efforts in developing environmentally cleaner solid propellants by scavenging the chlorine ion have focused on replacing a portion of the chorine-containing oxidant (i.e., ammonium perchlorate) with an alkali metal nitrate. The alkali metal (e.g., Li or Na) in the nitrate reacts with the chlorine ion to form an alkali metal chloride (i.e., a salt instead of HCl). While this technique can potentially reduce HCl formation, it also results in reduced ideal specific impulse (ISP). Here, we show using thermochemical calculations that using aluminum-lithium (Al-Li) alloy can reduce HCl formation by more than 95% (with lithium contents ≥15 mass%) and increase the ideal ISP by ∼7s compared to neat aluminum (using 80/20 mass% Al-Li alloy). Two solid propellants were formulated using 80/20 Al-Li alloy or neat aluminum as fuel additives. The halide scavenging effect of Al-Li propellants was verified using wet bomb combustion experiments (75.5±4.8% reduction in pH, ∝ [HCl], when compared to neat aluminum). Additionally, no measurable HCl evolution was detected using differential scanning calorimetry coupled with thermogravimetric analysis, mass spectrometry, and Fourier transform infrared absorption. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Direct anodic hydrochloric acid and cathodic caustic production during water electrolysis

    Science.gov (United States)

    Lin, Hui-Wen; Cejudo-Marín, Rocío; Jeremiasse, Adriaan W.; Rabaey, Korneel; Yuan, Zhiguo; Pikaar, Ilje

    2016-02-01

    Hydrochloric acid (HCl) and caustic (NaOH) are among the most widely used chemicals by the water industry. Direct anodic electrochemical HCl production by water electrolysis has not been successful as current commercially available electrodes are prone to chlorine formation. This study presents an innovative technology simultaneously generating HCl and NaOH from NaCl using a Mn0.84Mo0.16O2.23 oxygen evolution electrode during water electrolysis. The results showed that protons could be anodically generated at a high Coulombic efficiency (i.e. ≥ 95%) with chlorine formation accounting for 3 ~ 5% of the charge supplied. HCl was anodically produced at moderate strengths at a CE of 65 ± 4% together with a CE of 89 ± 1% for cathodic caustic production. The reduction in CE for HCl generation was caused by proton cross-over from the anode to the middle compartment. Overall, this study showed the potential of simultaneous HCl and NaOH generation from NaCl and represents a major step forward for the water industry towards on-site production of HCl and NaOH. In this study, artificial brine was used as a source of sodium and chloride ions. In theory, artificial brine could be replaced by saline waste streams such as Reverse Osmosis Concentrate (ROC), turning ROC into a valuable resource.

  13. Corrosion Behavior of Ni3(Si,Ti + 2Mo in Hydrochloric Acid Solution

    Directory of Open Access Journals (Sweden)

    Gadang Priyotomo

    2013-10-01

    Full Text Available The corrosion behavior of Ni3(Si,Ti + 2Mo intermetallic compound (L12 and (L12 + Niss mixture region has been investigated using an immersion test, polarization method and surface analytical method (scanning electron microscope and energy-dispersive X-Ray spectrometry in 0.5 kmol/m3 hydrochloric acid (HCl solution at 303 K.  In addition, the results obtained were compared to those of the L12 single-phase Ni3(Si,Ti intermetallic compound and C 276 alloy.  It was found that Ni3(Si,Ti + 2Mo had the preferential dissolution of L12 with a lower Mo concentration compared to (L12 + Niss mixture region.  From the immersion test and polarization curves, Ni3(Si,Ti + 2Mo and C276 showed the lowest corrosion resistance and the highest corrosion resistance in the solution, respectively.  From this work, It implied that unlike C276, Ni3(Si,Ti +2Mo intermetallic compound was difficult to form a stable passive film in HCl solution as well as Ni3(Si,Ti in the same solution.

  14. Variation of structures of ingredients of desiccated coconut during hydrolysis by hydrochloric acid at low temperature

    Directory of Open Access Journals (Sweden)

    Jian XIONG

    2017-10-01

    Full Text Available Abstract Owing to the high content of lignocellulose, desiccated coconut become a healthy material for dietary fiber supplementation. In this study, the changes in solubility of the fibers of desiccated coconut were evaluated. The changes of the pHs and weight losses were studied. Furthermore, variations of the ingredient structures of desiccated coconut by hydrolysis by hydrochloric acid were characterized by Fourier transform infrared spectroscopy (FTIR, X-ray diffraction (XRD and scanning electron microscopy (SEM. After hydrolysis 30 s, the pHs of all systems increased, while six hours later, the pH of only system with initial pH = 1.00 decreased. The decline of pH only existed in hydrolysis systems with initial pH = 1.00, there is no relevant with the quantities of desiccated coconut. The lower initial pH of hydrolysis system was, the less the intrinsic viscosity of the desiccated coconut after hydrolysis was, the small the crystallinity was. After hydrolysis, the microstructure of the desiccated coconut become looser, and the secondary structure of the coconut protein became more stable and ordered. The results suggest that the hydrolysis of desiccated coconut mainly occurred in the branched chain and the non-crystalline region of lignocellulose, which transforms some insoluble dietary fiber into soluble dietary fiber. This improves the nutritional value of desiccated coconut.

  15. Effect of foods and drinks on primary tooth enamel after erosive challenge with hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Késsia Suênia Fidelis de MESQUITA-GUIMARÃES

    2015-01-01

    Full Text Available The aim of this study was to evaluate the effect of industrialised foods and drinks on primary tooth enamel previously eroded with hydrochloric acid (HCl. The crowns of one hundred two specimens were subjected to an erosive challenge with HCl and randomly divided into six groups (n = 17: Chocolate Milk (Toddynho® - Pepsico - negative control; Petit Suisse Yogurt (Danoninho® - Danone; Strawberry Yogurt (Vigor; Apple puree (Nestlé; Fermented Milk (Yakult® - Yakult; and Home Squeezed Style Orange Juice (del Valle - positive control. The 28-day immersion cycles for the test products were performed twice daily and were interspersed with exposure of the test substrate to artificial saliva. Measurements of enamel surface microhardness (SMH were performed initially, after immersion in HCl and at 7, 14, 21 and 28 days of experimentation. A two-way ANOVA, according to a split-plot design, followed by the sum of squares decomposition and Tukey’s test, revealed a significant effect for the interaction between Foods and Drinks and Length of Exposure (p < 0.00001. Orange juice resulted in greater mineral loss of enamel after 28 days. None of the test products was associated with recovery of tooth enamel microhardness.

  16. Activation of Graphene Oxide with Hydrochloric Acid for Nitrate Removal from Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Abolghasem Alighardashi

    2017-11-01

    Full Text Available Long-term drinking of nitrate-contaminated water poses a serious risk to human health. The present study explores the possibility of enhancing the adsorption capacity of graphene oxide via activation with hydrochloric acid for nitrate removal from aqueous solutions. Experiments were performed in a batch reactor in which such major factors as pH, reaction time, and concentrations of both graphene oxide (GO and activated graphene oxide (AGO were used as variables. Nitrate removal efficiency was investigated using the One-Way ANOVA statistical test and SPSS-16 software. The chemical composition and solid structure of the synthesized AGO were analyzed using FE-SEM coupled with energy dispersive spectrometry (EDS. The micropore volumes of the samples were determined using the BET and BJH. The predominant composition (52% of the synthesized AGO was C and its mean pore diameter was 26.896 nm. The maximum adsorption capacity of AGO was estimated at 3333.33 mg/g. Based on the results, the AGO nano-structure may be recomended as a new means for nitrate removal from aqueous solutions.

  17. Densities, molar volumes, and isobaric expansivities of (d-xylose+hydrochloric acid+water) systems

    International Nuclear Information System (INIS)

    Zhang Qiufen; Yan Zhenning; Wang Jianji; Zhang Hucheng

    2006-01-01

    Densities of (d-xylose+HCl+water) have been measured at temperature in the range (278.15 to 318.15) K as a function of concentration of both d-xylose and hydrochloric acid. The densities have been used to estimate the molar volumes and isobaric expansivity of the ternary solutions. The molar volumes of the ternary solutions vary linearly with mole fraction of d-xylose. The standard partial molar volumes V 2,φ - bar for d-xylose in aqueous solutions of molality (0.2, 0.4, 0.7, 1.1, 1.6, and 2.1) mol.kg -1 HCl have been determined. In the investigated temperature range, the relation: V 2,φ - bar =c 1 +c 2 {(T/K)-273.15} 1/2 , can be used to describe the temperature dependence of the standard partial molar volumes. These results have, in conjunction with the results obtained in water, been used to deduce the standard volumes of transfer, Δ t V - bar , of d-xylose from water to aqueous HCl solutions. An increase in the transfer volume of d-xylose with increasing HCl concentrations has been explained by the stronger interactions of H + with the hydrophilic groups of d-xylose

  18. Two pyrazine derivatives as inhibitors of the cold rolled steel corrosion in hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Deng Shuduan, E-mail: dengshuduan@163.co [Faculty of Wood Science and Decoration Technology, Southwest Forestry University, Kunming 650224 (China); Li Xianghong; Fu Hui [Department of Fundamental Courses, Southwest Forestry University, Kunming 650224 (China)

    2011-02-15

    Research highlights: Two pyrazine derivatives of 2-aminopyrazine (AP) and 2-amino-5-bromopyrazine (ABP) are good inhibitors for the corrosion of steel in 1.0 M HCl solution. The inhibition efficiency follows the order: ABP > AP. The substitution Br of ABP is the additional centre of adsorption and increases the electron density of pyrazine ring, which can facilitate its adsorption on the metal surface. For either ABP or AP, the adsorption obeys Langmuir adsorption isotherm. Both ABP and AP act as mixed-type inhibitors. - Abstract: The inhibition effect of two pyrazine derivatives of 2-aminopyrazine (AP) and 2-amino-5-bromopyrazine (ABP) on the corrosion of cold rolled steel (CRS) in 1.0 M hydrochloric acid (HCl) was studied by weight loss, potentiodynamic polarization curves, and electrochemical impedance spectroscopy (EIS) methods. The results show that both AP and ABP are good inhibitors, and inhibition efficiency follows the order: ABP > AP. The adsorption of each inhibitor on CRS surface obeys Langmuir adsorption isotherm. Potentiodynamic polarization curves show that two pyrazine derivatives act as mixed-type inhibitors. EIS spectra exhibit one capacitive loop and confirm the inhibitive ability.

  19. Two pyrazine derivatives as inhibitors of the cold rolled steel corrosion in hydrochloric acid solution

    International Nuclear Information System (INIS)

    Deng Shuduan; Li Xianghong; Fu Hui

    2011-01-01

    Research highlights: → Two pyrazine derivatives of 2-aminopyrazine (AP) and 2-amino-5-bromopyrazine (ABP) are good inhibitors for the corrosion of steel in 1.0 M HCl solution. → The inhibition efficiency follows the order: ABP > AP. The substitution Br of ABP is the additional centre of adsorption and increases the electron density of pyrazine ring, which can facilitate its adsorption on the metal surface. → For either ABP or AP, the adsorption obeys Langmuir adsorption isotherm. → Both ABP and AP act as mixed-type inhibitors. - Abstract: The inhibition effect of two pyrazine derivatives of 2-aminopyrazine (AP) and 2-amino-5-bromopyrazine (ABP) on the corrosion of cold rolled steel (CRS) in 1.0 M hydrochloric acid (HCl) was studied by weight loss, potentiodynamic polarization curves, and electrochemical impedance spectroscopy (EIS) methods. The results show that both AP and ABP are good inhibitors, and inhibition efficiency follows the order: ABP > AP. The adsorption of each inhibitor on CRS surface obeys Langmuir adsorption isotherm. Potentiodynamic polarization curves show that two pyrazine derivatives act as mixed-type inhibitors. EIS spectra exhibit one capacitive loop and confirm the inhibitive ability.

  20. Inhibition of the corrosion of mild steel in hydrochloric acid by isatin and isatin glycine

    Directory of Open Access Journals (Sweden)

    B.I. Ita

    2006-12-01

    Full Text Available The inhibition of corrosion of mild steel in hydrochloric acid by isatin glycine (ING and isatin (IN at 30-60 oC and concentrations of 0.0001 M to 0.0005 M was studied via weight loss method. At the highest inhibitor concentration studied ING exhibited inhibition efficiency of 87% while IN exhibited 84% at 60 oC. A chemical adsorption mechanism was proposed on the basis of the temperature effect and obtained average activation energy values of 143.9 kJ/mol for ING and 118.5 kJ/mol for IN. The two inhibitors were confirmed to obey the Langmuir adsorption isotherm equation at the concentrations studied. Also a first-order type of mechanism was proposed from the kinetic treatment of the result. The difference in the inhibitory properties of the inhibitors was explained in terms of the difference in their molecular structures and solubility rather than difference in molecular weights alone.

  1. Studies on the solvent extraction behaviour of Pu(IV) from nitric acid, nitric-perchloric acid and hydrochloric acids, by di,2-ethylhexyl phosphoric acid (HDEHP)

    International Nuclear Information System (INIS)

    Phal, D.G.; Kannan, S.K.; Ramakrishna, V.V.

    1994-01-01

    Extraction of plutonium (IV) from aqueous nitric acid, nitric-perchloric acid and hydrochloric acids by di,2-ethylhexyl phosphoric acid, the dimeric form of which is represented as H 2 Y 2 , in different diluents (dodecane, toluene and chloroform) was investigated. The composition of the extracted Pu(IV) species were found to be Pu(NO 3 ) 2 (HY) 2 , Pu(NO 3 )(ClO 4 )(HY 2 ) 2 , PuClY(HY 2 ) 2 and PuCl 2 (HY 2 ) 2 from nitric, nitric-perchloric and hydrochloric acids respectively, the last one being pre-dominant at high aqueous acidities (i.e. 5M HCl). Synergic enhancement in the extraction of Pu(IV) from different aqueous media, by the addition of thenoyltrifluoroacetone (HTTA) to HDEHP was also investigated and was attributed to the formation and extraction of the species PuX(TTA)(HY 2 ) 2 , and Pu(TTA) 2 (HY 2 ) 2 where X=Cl - or NO 3 - . The addition of the neutral extractant TOPO to H 2 Y 2 also resulted in synergism. The possible equilibria in these systems were inferred and the corresponding equilibrium constants determined. (author). 24 refs., 10 figs., 10 tabs

  2. Stepwise hydrochloric acid extraction of monazite hydroxides for the recovery of cerium lean rare earths, cerium, uranium and thorium

    International Nuclear Information System (INIS)

    Swaminathan, T.V.; Nair, V.R.; John, C.V.

    1988-01-01

    Monazite sand is normally processed by the caustic soda route to produce mixed rare earth chloride, thorium hydroxide and trisodium phosphate. Bulk of the mixed rare earth chloride is used for the preparation of FC catalysts. Recently some of the catalyst producers have shown preference to cerium depleted (lanthanum enriched) rare earth chloride rather than the natural rare earth chloride obtained from monazite. Therefore, a process for producing cerium depleted rare earth chloride, cerium, thorium and uranium from rare earth + thorium hydroxide obtained by treating monazite, based on stepwise hydrochloric acid extraction, was developed in the authors laboratory. The process involves drying of the mixed rare earth-thorium hydroxide cake obtained by monazite-caustic soda process followed by stepwise extraction of the dried cake with hydrochloric acid under specified conditions

  3. Removing hydrochloric acid exhaust products from high performance solid rocket propellant using aluminum-lithium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Terry, Brandon C., E-mail: terry13@purdue.edu [School of Aeronautics and Astronautics, Purdue University, Zucrow Laboratories, 500 Allison Rd, West Lafayette, IN 47907 (United States); Sippel, Travis R. [Department of Mechanical Engineering, Iowa State University, 2025 Black Engineering, Ames, IA 50011 (United States); Pfeil, Mark A. [School of Aeronautics and Astronautics, Purdue University, Zucrow Laboratories, 500 Allison Rd, West Lafayette, IN 47907 (United States); Gunduz, I.Emre; Son, Steven F. [School of Mechanical Engineering, Purdue University, Zucrow Laboratories, 500 Allison Rd, West Lafayette, IN 47907 (United States)

    2016-11-05

    Highlights: • Al-Li alloy propellant has increased ideal specific impulse over neat aluminum. • Al-Li alloy propellant has a near complete reduction in HCl acid formation. • Reduction in HCl was verified with wet bomb experiments and DSC/TGA-MS/FTIR. - Abstract: Hydrochloric acid (HCl) pollution from perchlorate based propellants is well known for both launch site contamination, as well as the possible ozone layer depletion effects. Past efforts in developing environmentally cleaner solid propellants by scavenging the chlorine ion have focused on replacing a portion of the chorine-containing oxidant (i.e., ammonium perchlorate) with an alkali metal nitrate. The alkali metal (e.g., Li or Na) in the nitrate reacts with the chlorine ion to form an alkali metal chloride (i.e., a salt instead of HCl). While this technique can potentially reduce HCl formation, it also results in reduced ideal specific impulse (I{sub SP}). Here, we show using thermochemical calculations that using aluminum-lithium (Al-Li) alloy can reduce HCl formation by more than 95% (with lithium contents ≥15 mass%) and increase the ideal I{sub SP} by ∼7 s compared to neat aluminum (using 80/20 mass% Al-Li alloy). Two solid propellants were formulated using 80/20 Al-Li alloy or neat aluminum as fuel additives. The halide scavenging effect of Al-Li propellants was verified using wet bomb combustion experiments (75.5 ± 4.8% reduction in pH, ∝ [HCl], when compared to neat aluminum). Additionally, no measurable HCl evolution was detected using differential scanning calorimetry coupled with thermogravimetric analysis, mass spectrometry, and Fourier transform infrared absorption.

  4. Removing hydrochloric acid exhaust products from high performance solid rocket propellant using aluminum-lithium alloy

    International Nuclear Information System (INIS)

    Terry, Brandon C.; Sippel, Travis R.; Pfeil, Mark A.; Gunduz, I.Emre; Son, Steven F.

    2016-01-01

    Highlights: • Al-Li alloy propellant has increased ideal specific impulse over neat aluminum. • Al-Li alloy propellant has a near complete reduction in HCl acid formation. • Reduction in HCl was verified with wet bomb experiments and DSC/TGA-MS/FTIR. - Abstract: Hydrochloric acid (HCl) pollution from perchlorate based propellants is well known for both launch site contamination, as well as the possible ozone layer depletion effects. Past efforts in developing environmentally cleaner solid propellants by scavenging the chlorine ion have focused on replacing a portion of the chorine-containing oxidant (i.e., ammonium perchlorate) with an alkali metal nitrate. The alkali metal (e.g., Li or Na) in the nitrate reacts with the chlorine ion to form an alkali metal chloride (i.e., a salt instead of HCl). While this technique can potentially reduce HCl formation, it also results in reduced ideal specific impulse (I_S_P). Here, we show using thermochemical calculations that using aluminum-lithium (Al-Li) alloy can reduce HCl formation by more than 95% (with lithium contents ≥15 mass%) and increase the ideal I_S_P by ∼7 s compared to neat aluminum (using 80/20 mass% Al-Li alloy). Two solid propellants were formulated using 80/20 Al-Li alloy or neat aluminum as fuel additives. The halide scavenging effect of Al-Li propellants was verified using wet bomb combustion experiments (75.5 ± 4.8% reduction in pH, ∝ [HCl], when compared to neat aluminum). Additionally, no measurable HCl evolution was detected using differential scanning calorimetry coupled with thermogravimetric analysis, mass spectrometry, and Fourier transform infrared absorption.

  5. Synthesis and characterization of a novel organic corrosion inhibitor for mild steel in 1 M hydrochloric acid

    Science.gov (United States)

    Ahmed, Mohammed H. Othman; Al-Amiery, Ahmed A.; Al-Majedy, Yasmin K.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar; Gaaz, Tayser Sumer

    2018-03-01

    The synthesis and characterization of a novel organic corrosion inhibitor (4-(3-mercapto-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazin-6-yl)phenol), for mild steel in 1 M hydrochloric acid (HCl) has been successfully reported for the first time. The inhibitor evaluated as corrosion inhibitor for mild steel in 1 M of Hydrochloric acid solution using electrochemical impedance spectroscopy (EIS), and electrochemical frequency modulation (EFM) measurement techniques. Changes in the impedance parameters suggested an adsorption of the inhibitor onto the mild steel surface, leading to the formation of protective films. The results show that the inhibition efficiencies increased with increasing the concentrations of the inhibitors and decreased with increasing temperature. The maximum inhibition efficiency up to 67% at the maximum concentration 0.5 mM. This shows that those inhibitors are effective in helping to reduce and slowing down the corrosion process that occurs to mild steel with a hydrochloric acid solution by providing an organic inhibitor for the mild steel that can be weakened by increasing the temperature. The adsorption process of the synthesized organic inhibitor depends on its electronic characteristics in addition to steric effects and the nature of metal surface, temperature degree and the varying degrees of surface-site activity. The synthesized inhibitor molecules were absorbed by metal surface and follow Langmuir isotherms.

  6. Synthesis and characterization of a novel organic corrosion inhibitor for mild steel in 1 M hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Mohammed H. Othman Ahmed

    2018-03-01

    Full Text Available The synthesis and characterization of a novel organic corrosion inhibitor (4-(3-mercapto-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazin-6-ylphenol, for mild steel in 1 M hydrochloric acid (HCl has been successfully reported for the first time. The inhibitor evaluated as corrosion inhibitor for mild steel in 1 M of Hydrochloric acid solution using electrochemical impedance spectroscopy (EIS, and electrochemical frequency modulation (EFM measurement techniques. Changes in the impedance parameters suggested an adsorption of the inhibitor onto the mild steel surface, leading to the formation of protective films. The results show that the inhibition efficiencies increased with increasing the concentrations of the inhibitors and decreased with increasing temperature. The maximum inhibition efficiency up to 67% at the maximum concentration 0.5 mM. This shows that those inhibitors are effective in helping to reduce and slowing down the corrosion process that occurs to mild steel with a hydrochloric acid solution by providing an organic inhibitor for the mild steel that can be weakened by increasing the temperature. The adsorption process of the synthesized organic inhibitor depends on its electronic characteristics in addition to steric effects and the nature of metal surface, temperature degree and the varying degrees of surface-site activity. The synthesized inhibitor molecules were absorbed by metal surface and follow Langmuir isotherms. Keywords: Corrosion, Inhibitor, Mild steel, EIS spectroscopy

  7. Evaluation tissue dissolution property of 2.5 % Sodium Hypochlorite Prepared by Hydrochloric Acid and Sodium Bicarbonate: An in vitro

    Directory of Open Access Journals (Sweden)

    Hamid Razavian

    2016-08-01

    Full Text Available Successful endodontic treatment requires chemical preparation in addition to mechanical preparation. The most common material for chemical preparations is sodium hypochlorite. One way to reduce the effects of pH adjustment is the use of sodium hypochlorite. The present paper was conducted to examine the effect of dilution with hydrochloric acid and sodium bicarbonate and reduce pH on ability of tissue solubility of sodium hypochlorite. The present study was conducted in vitro on bovine muscle tissue. Ability of tissue solubility was conducted in four groups respectively with active ingredient including 1 sodium hypochlorite diluted with distilled water 2 sodium hypochlorite diluted with sodium bicarbonate 3 sodium hypochlorite diluted with hydrochloric acid and finally 4 distilled water (control group. Each sample was firstly weighed and then placed in contact with 10 m/L solution for 60 minutes (five 12 -minute intervals. The sample was weighted every five minutes and solution was renewed. The results were analyzed using SPSS-21 Software based on variance analysis, Tukey and T-test (α=0.05. The findings showed that there was significant difference between first, second and third groups in terms of ability of tissue solubility. However, the tissue solubility in second and third groups was lower than first group and it was similar in second and third groups (P Value <0.001. Reduction of sodium bicarbonate PH using sodium hypochlorite and hydrochloric acid reduces ability of tissue solubility in sodium hypochlorite.

  8. Copper-promoted cementation of antimony in hydrochloric acid system: A green protocol

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Lian-Kui; Li, Ying-Ying; Cao, Hua-Zhen; Zheng, Guo-Qu, E-mail: zhenggq@zjut.edu.cn

    2015-12-15

    Highlights: • Antimony can be efficiently removed by cementation with copper powder. • Cemented antimony is in the form of Cu{sub 2}Sb. • Consumed copper powder is transformed to CuCl. • The cementation is a chemically controlled step. • No toxic stibine generates during the cementation process. - Abstract: A new method of recovering antimony in hydrochloric acid system by cementation with copper powder was proposed and carried out at laboratory scale. Thermodynamic analysis and cyclic voltammetry test were conducted to study the cementation process. This is a novel antimony removal technology and quite meets the requirements of green chemistry. The main cement product Cu{sub 2}Sb is a promising anodic material for lithium and sodium ion battery. And nearly all consumed copper powder are transformed into CuCl which is an important industrial material. The effect of reaction temperature, stoichiometric ratio of Cu to Sb(III), stirring rate and concentration of HCl on the cementation efficiency of antimony were investigated in detail. Optimized cementation condition is obtained at 60 °C for 120 min and stirring rate of 600 rpm with Cu/Sb(III) stoichiometric ratio of 6 in 3 mol L{sup −1} HCl. At this time, nearly all antimony can be removed by copper powder and the cementation efficiency is over 99%. The structure and morphologies of the cement products were characterized by X-ray diffraction and scanning electron microscopy, respectively. Results show that the reaction temperature has little influence on the morphology of the cement products which consist of particles with various sizes. The activation energy of the cementation antimony on copper is 37.75 kJ mol{sup −1}, indicating a chemically controlled step. Inductively coupled plasma mass spectrometry results show that no stibine generates during the cementation process.

  9. Adsorption and purification of radiogallium in hydrochloric acid and metal chloride solutions by non-ionic resin of macro-reticular type

    International Nuclear Information System (INIS)

    Imai, Kiyoko; Watari, Kazuo; Ohno, Shigeru; Ohmiya, Toshinobu; Kuroda, Emi; Izawa, Masami.

    1986-01-01

    Adsorption behavior of radiogallium ( 67 Ga, 68 Ga) on non-ionic MR resin (XAD-7) from hydrochloric acid, lithium chloride and other metal chloride solutions, and purification of 68 Ga by this resin were studied. Radiogallium was adsorbed on XAD-7 rapidly and quantitatively from the solution of higher chloride concentration than 6M. The adsorption behavior is similar to that obtained with 59 Fe and 195 Au previously. Based on adsorption data, elimination of trace amount of 68 Ge commonly contained in 68 Ga milked from a 68 Ge/ 68 Ga generator was tried. When 68 Ga-6M hydrochloric acid solution containing 68 Ge was passed through a XAD-7 column, all the activity was transferred on the column. After eliminating 68 Ge fraction with 3M hydrochloric acid, 68 Ga was obtained in high purity by eluting with 0.1M hydrochloric acid. (author)

  10. Characterization of Polyamide 66 membranes prepared by phase inversion using formic acid and hydrochloric acid such as solvents

    Directory of Open Access Journals (Sweden)

    Patrícia Poletto

    2011-12-01

    Full Text Available The membranes properties prepared from water/formic acid (FA/ polyamide 66 (PA66 and water/hydrochloric acid (HCl/polyamide 66 (PA 66 systems has been studied. The different solvents interact distinctly with the polymer, affecting the membrane morphology. The asymmetric structure of the membranes showed a dense top layer and a porous sublayer. The membranes M-HCl prepared from HCl/PA 66 system showed a larger dense layer (around 23 μm in compared to those prepared from FA/PA 66 system (M-FA (around 10 μm. The membrane morphology was a determinant factor in results of water absorption, porosity and pure water flux. The lower thickness of dense layer in M-FA membranes resulted in a higher water absorption and, consequently, porosity, approximately 50%, compared with M-HCl membranes, approximately 15%. The same trend was observed to permeate flux, the lower thickness of dense layer higher pure water flux.

  11. Inhibitive effect of a naturally-occurring substance, tobacco, on the dissolution of mild steel in hydrochloric acid

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, K; Srivastava, P

    1980-12-01

    A number of naturally-occurring substances has been found to be effective inhibitors for the dissolution of mild steel in hydrochloric acid. The alkaloids nicotine and papaverine, contained in natural products such as tobacco leaves and black pepper, have proved themselves as excellent inhibitors. Considering the low cost of tobacco leaves, detailed studies were made with these, and they have been found to form an effective inhibitor under all practical conditions. Adsorption studies based on weight-loss measurements showed that adsorption of inhibitor obeys Freundlich's adsorption isoth

  12. ESR study of /sup 99/Tc(II) complex formed by reduction of ammonium pertechnetate with ascorbic acid in concentrated hydrochloric acid

    Energy Technology Data Exchange (ETDEWEB)

    Kudo, T; Tsuchihashi, N; Ogata, T

    1987-07-30

    Paramagnetic /sup 99/Tc complex formed by the reduction of ammonium pertechnetate by ascorbic acid with excess sodium nitrite in concentrated hydrochloric acid was investigated by ESR technique. This complex had total electron spin S=1/2 and the obtained ESR parameters are 2.032, 2.043; and 264, 108 gauss, respectively. It was concluded that the formed species was low spin /sup 99/Tc(II) complex. (author) 13 refs.

  13. Growth and membrane fluidity of food-borne pathogen Listeria monocytogenes in the presence of weak acid preservatives and hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Ioannis eDiakogiannis

    2013-06-01

    Full Text Available This study addresses a major issue in microbial food safety, the elucidation of correlations between acid stress and changes in membrane fluidity of the pathogen Listeria monocytogenes. In order to assess the possible role that membrane fluidity changes play in L. monocytogenes tolerance to antimicrobial acids (acetic, lactic, hydrochloric acid at low pH or benzoic acid at neutral pH, the growth of the bacterium and the gel-to-liquid crystalline transition temperature point (Tm of cellular lipids of each adapted culture was measured and compared with unexposed cells. The Tm of extracted lipids was measured by Differential Scanning Calorimetry (DSC. A trend of increasing Tm values but not of equal extent was observed upon acid tolerance for all samples and this increase is not directly proportional to each acid antibacterial action. The smallest increase in Tm value was observed in the presence of lactic acid, which presented the highest antibacterial action. In the presence of acids with high antibacterial action such as acetic, hydrochloric acid or low antibacterial action such as benzoic acid, increased Tm values were measured. The Tm changes of lipids were also correlated with our previous data about fatty acid changes to acid adaptation. The results imply that the fatty acid changes are not the sole adaptation mechanism for decreased membrane fluidity (increased Tm. Therefore, this study indicates the importance of conducting an in-depth structural study on how acids commonly used in food systems affect the composition of individual cellular membrane lipid molecules.

  14. Modification of ntezi bentonite structure by hydrochloric acid: process kinetics and structural properties of the modified samples

    International Nuclear Information System (INIS)

    Ajemba, R.O.

    2014-01-01

    Bentonite from Ntezi was modified by reacting it with different concentrations of hydrochloric acid solutions. The modified samples were analysed by x-ray fluorescence. The kinetics of the modification reaction was studied by performing the experiment at different temperatures and times. Results of the analysis of the modified samples showed that the octahedral cations were removed which altered the chemical composition of the bentonite. The surface area and adsorptive capacity of the bentonite were improved after the modification. The kinetic studies showed that the acid modification reaction is controlled by the product layer diffusion and can be represented by (1-(l-X)/sup 1/3)/sup 2/ = k t; where, X is the fraction of the bentonite dissolved at time t. The activation energy was determined to be 24.98 kJ/mol. (author)

  15. 2.4. The kinetics of hydrochloric-acid decomposition of calcined concentrate of boron raw material of Ak-Arkhar Deposit

    International Nuclear Information System (INIS)

    Mirsaidov, U.M.; Kurbonov, A.S.; Mamatov, E.D.

    2015-01-01

    Present article is devoted to kinetics of hydrochloric-acid decomposition of calcined concentrate of boron raw material of Ak-Arkhar Deposit. The experimental data of dependence of hydrochloric-acid decomposition of calcined boron raw material for boron oxide extraction on temperature (20-80 deg C) and process duration (15-60 min) were considered. It was defined that at temperature increasing the boron oxide extraction from borosilicate raw material increases from 24.1 till 86.8%. The constants of decomposition rate of boron raw material were calculated.

  16. The Corrosion Behavior of Nickel and Inconel 600 in Sodium Hydroxide and Hydrochloric Acid Solution at 280 .deg. C

    International Nuclear Information System (INIS)

    Lee, Ihh Chong; Suk, Tae Won

    1980-01-01

    The corrosion behavior of nickel and Inconel 600 has been investigated by the weight change measurement method at pH ranges 3∼13 of the solution. The specimens were exposed to aqueous solutions in a static autoclave at 280 .deg. C for 210 hours. The pH of the solutions was adjusted by hydrochloric acid and sodium hydroxide and the dissolved oxygen concentration was fixed as 10 ppb by using pure nitrogen gas. Weight loss of Inconel 600 was much less than that of nickel over the tested pH ranges. At pH 9.5, nickel and Inconel 600 showed the minimum weight loss phenomenon and the values of weight loss were 1.5mg/dm 2 and 0.9mg/dm 2 , respectively. Microscopic examination showed that nickel surface was attacked uniformly, whereas Inconel 600 surface was not greatly

  17. Physical and chemical mechanism underlying ultrasonically enhanced hydrochloric acid leaching of non-oxidative roasting of bastnaesite.

    Science.gov (United States)

    Zhang, Dongliang; Li, Mei; Gao, Kai; Li, Jianfei; Yan, Yujun; Liu, Xingyu

    2017-11-01

    In this study, we investigated an alternative to the conventional hydrochloric acid leaching of roasted bastnaesite. The studies suggested that the rare earth oxyfluorides in non-oxidatively roasted bastnaesite can be selectively leached only at elevated temperatures Further, the Ce(IV) in oxidatively roasted bastnaesite does not leach readily at low temperatures, and it is difficult to induce it to form a complex with F - ions in order to increase the leaching efficiency. Moreover, it is inevitably reduced to Ce(III) at elevated temperatures. Thus, the ultrasonically-assisted hydrochloric acid leaching of non-oxidatively roasted bastnaesite was studied in detail, including, the effects of several process factors and the, physical and chemical mechanisms underlying the leaching process. The results show that the leaching rate for the ultrasonically assisted process at 55°C (65% rare earth oxides) is almost the same as that for the conventional leaching process at 85°C. Based on the obtained results, it is concluded that ultrasonic cavitation plays a key role in the proposed process, resulting not only in a high shear stress, which damages the solid surface, but also in the formation of hydroxyl radicals (OH) and hydrogen peroxide (H 2 O 2 ). Standard electrode potential analysis and experimental results indicate that Ce(III) isoxidized by the hydroxyl radicals to Ce(IV), which can be leached with F - ions in the form of a complex, and that the Ce(IV) can subsequently be reduced to Ce(III) by the H 2 O 2. This prevents the Cl - ions in the solution from being oxidized to form chlorine. These results imply that the ultrasonically-assisted process can be used for the leaching of non-oxidatively roasted bastnaesite at low temperatures in the absence of a reductant. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Nicotinic acid as a nontoxic corrosion inhibitor for hot dipped Zn and Zn-Al alloy coatings on steels in diluted hydrochloric acid

    Energy Technology Data Exchange (ETDEWEB)

    Ju Hong [Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071 (China); Graduate School, Chinese Academy of Sciences, Beijing 100039 (China); Li Yan [Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071 (China)], E-mail: yanlee@ms.qdio.ac.cn

    2007-11-15

    The inhibition effect of nicotinic acid for corrosion of hot dipped Zn and Zn-Al alloy coatings in diluted hydrochloric acid was investigated using quantum chemistry analysis, weight loss test, electrochemical measurement, and scanning electronic microscope (SEM) analysis. Quantum chemistry calculation results showed that nicotinic acid possessed planar structure with a number of active centers, and the populations of the Mulliken charge, the highest occupied molecular orbital (HOMO), and the lowest unoccupied molecular orbital (LUMO) were found mainly focused around oxygen and nitrogen atoms, and the cyclic of the benzene as well. The results of weight loss test and electrochemical measurement indicated that inhibition efficiency (IE%) increased with inhibitor concentration, and the highest inhibition efficiency was up to 96.7%. The corrosion inhibition of these coatings was discussed in terms of blocking the electrode reaction by adsorption of the molecules at the active centers on the electrode surface. It was found that the adsorption of nicotinic acid on coating surface followed Langmuir adsorption isotherm with single molecular layer, and nicotinic acid adsorbed on the coating surface probably by chemisorption. Nicotinic acid, therefore, can act as a good nontoxic corrosion inhibitor for hot dipped Zn and Zn-Al alloy coatings in diluted hydrochloric acid solution.

  19. Rapid anion exchange separation of fermium with mineral acid-methyl alcohol mixed media

    International Nuclear Information System (INIS)

    Usuda, S.; Shinohara, N.; Ichikawa, S.; Suzuki, T.

    1987-01-01

    Anion exchange separation of 250 Fm (30 m) synthesized by the 12 C+ 242 Pu and 16 O+ 238 U reactions was investigated with mineral acid-methyl alcohol mixed media at elevated temperature. Fermium was chromatographically separated from the other transplutonium elements, the target materials and an Al catcher foil by anion exchange with mixtures of nitric acid and methyl alcohol. By use of the mixed media of hydrochloric acid and methyl alcohol, Fm together with Cf was separated from Al, Am, Cm, Pu, U and from major fission products. The separation systems are suitable for rapid separation and immediate alpha-counting source preparation of Fm. (author) 22 refs.; 4 figs

  20. Di-n-butylamine as an inhibitor for the corrosion of aluminium alloys in hydrochloric acid solutions

    Energy Technology Data Exchange (ETDEWEB)

    Unni, V K.V.; Rama Char, T L

    1965-01-01

    Di-n-butylamine is a satisfactory inhibitor for the corrosion of aluminum-manganese alloy in hydrochloric acid solutions. Polarization studies indicate that the anode polarization is negligible, whereas the cathode polarization is appreciable and is increased by the inhibitor. The Tafel plot holds good in this case. The dissolution of the metal is electrochemical in character; the corrosion process appears to be under cathodic control. The efficiency increases with time, the effect being quite significant up to about 3 hr. It increases with increases in concentration of the inhibitor up to a certain value beyond which it is constant. The values increase with acid concentration up to 1.25 N., and remain practically unchanged thereafter. An acid concentration of 1.25 N. and an inhibitor concentration of 0.5 g per liter of nitrogen can be regarded as the optimum from the viewpoint of efficiency, the value being in the range 57-84%. The efficiency of the inhibitor for the aluminum-manganese alloy is about the same order as for pure aluminum. (10 refs.)

  1. A kinetic study of plutonium dioxide dissolution in hydrochloric acid using iron (II) as an electron transfer catalyst

    International Nuclear Information System (INIS)

    Fife, K.W.

    1996-09-01

    Effective dissolution of plutonium dioxide has traditionally been accomplished by contact with strong nitric acid containing a small amount of fluoride at temperatures of ∼ 100 C. In spite of these aggressive conditions, PuO 2 dissolution is sometimes incomplete requiring additional contact with the solvent. This work focused on an alternative to conventional dissolution in nitric acid where an electron transfer catalyst, Fe(II), was used in hydrochloric acid. Cyclic voltammetry was employed as an in-situ analytical technique for monitoring the dissolution reaction rate. The plutonium oxide selected for this study was decomposed plutonium oxalate with > 95% of the material having a particle diameter (< 70 microm) as determined by a scanning laser microscopy technique. Attempts to dry sieve the oxide into narrow size fractions prior to dissolution in the HCl-Fe(II) solvent system failed, apparently due to significant interparticle attractive forces. Although sieve splits were obtained, subsequent scanning laser microscopy analysis of the sieve fractions indicated that particle segregation was not accomplished and the individual sieve fractions retained a particle size distribution very similar to the original powder assemblage. This phenomena was confirmed through subsequent dissolution experiments on the various screen fractions which illustrated no difference in kinetic behavior between the original oxide assemblage and the sieve fractions

  2. Green approach to corrosion inhibition of mild steel in hydrochloric acid and sulphuric acid solutions by the extract of Murraya koenigii leaves

    Energy Technology Data Exchange (ETDEWEB)

    Quraishi, M.A., E-mail: maquraishi@rediffmail.com [Department of Applied Chemistry, Institute of Technology, Banaras Hindu University, Varanasi 221005 (India); Singh, Ambrish; Singh, Vinod Kumar [Udai Pratap Autonomous College, Varanasi 221002 (India); Yadav, Dileep Kumar; Singh, Ashish Kumar [Department of Applied Chemistry, Institute of Technology, Banaras Hindu University, Varanasi 221005 (India)

    2010-07-01

    The inhibition of the corrosion of mild steel in hydrochloric acid and sulphuric acid solutions by the extract of Murraya koenigii leaves has been studied using weight loss, electrochemical impedance spectroscopy (EIS), linear polarization and potentiodynamic polarization techniques. Inhibition was found to increase with increasing concentration of the leaves extract. The effect of temperature, immersion time and acid concentration on the corrosion behavior of mild steel in 1 M HCl and 0.5 M H{sub 2}SO{sub 4} with addition of extract was also studied. The inhibition was assumed to occur via adsorption of the inhibitor molecules on the metal surface. The adsorption of the extract on the mild steel surface obeys the Langmuir adsorption isotherm. The activation energy as well as other thermodynamic parameters (Q, {Delta}H*, and {Delta}S*) for the inhibition process was calculated. These thermodynamic parameters show strong interaction between inhibitor and mild steel surface. The results obtained show that the extract of the leaves of M. koenigii could serve as an effective inhibitor of the corrosion of mild steel in hydrochloric and sulphuric acid media.

  3. Interaction between amylose and 1-butanol during 1-butanol-hydrochloric acid hydrolysis of normal rice starch.

    Science.gov (United States)

    Hu, Xiuting; Wei, Benxi; Zhang, Bao; Li, Hongyan; Xu, Xueming; Jin, Zhengyu; Tian, Yaoqi

    2013-10-01

    The aim of this study was to examine the interaction between amylose and 1-butanol during the 1-butanol-hydrochloric acid (1-butanol-HCl) hydrolysis of normal rice starch. The interaction model between amylose and 1-butanol was proposed using gas chromatography-mass spectrometry (GC-MS), (13)C cross polarization and magic angle spinning NMR analysis ((13)C CP/MAS NMR), differential scanning calorimetry (DSC), and thermalgravimetric analysis (TGA). GC-MS data showed that another form of 1-butanol existed in 1-butanol-HCl-hydrolyzed normal rice starch, except in the form of free molecules absorbed on the starch granules. The signal of 1-butanol-HCl-hydrolyzed starch at 100.1 ppm appeared in the (13)C CP/MAS NMR spectrum, indicating that the amylose-1-butanol complex was formed. DSC and TGA data also demonstrated the formation of the complex, which significantly affected the thermal properties of normal rice starch. These findings revealed that less dextrin with low molecular weight formed might be attributed to resistance of this complex to acid during 1-butanol-HCl hydrolysis. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  4. Inhibition of Aluminium Corrosion in Hydrochloric Acid Using Nizoral and the Effect of Iodide Ion Addition

    OpenAIRE

    I. B. Obot; N. O. Obi-Egbedi

    2010-01-01

    The effect of nizoral (NZR) on the corrosion inhibition of aluminium alloy AA 1060 in 2 M HCl solution was investigated using the mylius thermometric technique. Results of the study revealed that nizoral acts as corrosion inhibitor for aluminium in the acidic medium. In general, at constant acid concentration, the inhibition efficiency increases with increase in the inhibitor concentration. The addition of KI to the inhibitor enhanced the inhibition efficiency to a considerable extent. The ad...

  5. Inhibition of Aluminium Corrosion in Hydrochloric Acid Using Nizoral and the Effect of Iodide Ion Addition

    Directory of Open Access Journals (Sweden)

    I. B. Obot

    2010-01-01

    Full Text Available The effect of nizoral (NZR on the corrosion inhibition of aluminium alloy AA 1060 in 2 M HCl solution was investigated using the mylius thermometric technique. Results of the study revealed that nizoral acts as corrosion inhibitor for aluminium in the acidic medium. In general, at constant acid concentration, the inhibition efficiency increases with increase in the inhibitor concentration. The addition of KI to the inhibitor enhanced the inhibition efficiency to a considerable extent. The adsorption of nizoral onto the aluminium surface was found to obey the Fruendlich adsorption isotherm. The value of the free energy for the adsorption process shows that the process is spontaneous.

  6. Transpassive dissolution of alloy 625, chromium, nickel, and molybdenum in high-temperature solutions containing hydrochloric acid and oxygen

    International Nuclear Information System (INIS)

    Kritzer, P.; Boukis, N.; Dinjus, E.

    2000-01-01

    Coupons of nickel, molybdenum, chromium, and the nickel-based Alloy 625 (UNS 06625) were corroded in strongly oxidizing hydrochloric acid (HCl) solutions at 350 C and a pressure (p) of 24 MPa, with reaction times between 0.75 h and 50 h. For Alloy 625, the effect of surface roughness also was investigated. Nickel and molybdenum showed strong material loss after only 5 h of reaction as a result of the instability of the solid oxides formed under experimental conditions. The attack on chromium started at the grain boundaries. At longer reaction times, thick, spalling oxide layers formed on the surface. The attack on Alloy 625 also started at the grain boundaries and at inclusions leading to the formation of small pits. On polished surfaces, the growth of these pits occurred faster than on nonpolished surfaces, but fewer pits grew. Corrosion products formed at the surface consisted of oxygen and chromium. On isolated spots, nickel- and chlorine-containing products also were found

  7. Magnesium hydroxide as the neutralizing agent for radioactive hydrochloric acid solutions

    International Nuclear Information System (INIS)

    Palmer, M.J.; Fife, K.W.

    1995-10-01

    The current technology at Los Alamos for removing actinides from acidic chloride waste streams is precipitation with approximately 10 M potassium hydroxide. Although successful, there are many inherent drawbacks to this precipitation technique which will be detailed in this paper. Magnesium hydroxide (K sp = 1.3 x 10 -11 ) has limited solubility in water and as a result of the common ion effect, cannot generate a filtrate with a pH greater than 9. At a pH of 9, calcium (K sp = 5.5 x 10 -6 ) will not coprecipitate as the hydroxide. This is an important factor since many acidic chloride feeds to hydroxide precipitation contain significant amounts of calcium. In addition, neutralization with Mg(OH) 2 produces a more filterable precipitate because neutralization occurs as the Mg(OH) 2 is dissolved by the acid rather than as a result of the much faster liquid/liquid reaction of KOH with the waste acid. This slower solid/liquid reaction allows time for crystal growth to occur and produces more easily filterable precipitates. On the other hand, neutralization of spent acid with strong KOH that yields numerous hydroxide ions in solution almost instantaneously forming a much larger volume of small crystallites that result in gelatinous, slow-filtering precipitates. Magnesium hydroxide also offers a safety advantage. Although mildly irritating, it is a weak base and safe and easy to handle. From a waste minimization perspective, Mg(OH) 2 offers many advantages. First, the magnesium hydroxide is added as a solid. This step eliminates the diluent water used in KOH neutralizations. Secondly, because the particle size of the precipitate is larger, more actinides are caught on the filter paper resulting in a smaller amount of actinide being transferred to the TA-50 Liquid Waste Treatment Facility. Third, the amount of solids that must be reprocessed is significantly smaller resulting in less waste generation from the downstream processes

  8. Simultaneous Recovery of Hydrogen and Chlorine from Industrial Waste Dilute Hydrochloric Acid

    Directory of Open Access Journals (Sweden)

    N. Paidimarri

    2016-01-01

    Full Text Available Recovery of chlorine from byproduct HCl has inevitable commercial importance in industries lately because of insufficient purity or too low concentration to recycle it. Instead it is being neutralized in industries before disposing to meet stringent environmental conditions. Although recovery through catalytic oxidation processes is studied since the 19th century, their high operating conditions combined with sluggish reaction kinetics and low single pass conversions make electrolysis a better alternative. The present motive of this work is to develop a novel electrolysis process which in contrast to traditional processes effectively recovers both hydrogen and chlorine from dilute HCl. For this, an electrolytic cell with an Anionic Exchange Membrane has been designed which only allows the passage of chlorine anions from catholyte to anolyte separating the gasses in a single step. The catholyte can be as low as 3.59 wt% because of fixed anolyte concentration of 1.99 wt% which minimizes oxygen formation. Preliminary results show that the simultaneous recovery of hydrogen and chlorine is possible with high conversion up to 98%. The maximum current density value for 4.96 cm2 membrane surface area (70% active surface area is 2.54 kAm−2, which is comparable with reported commercial processes. This study is expected to be useful for process intensification of the same in a continuous process environment.

  9. Extraction of heavy metals from MSWI fly ash using hydrochloric acid and sodium chloride solution.

    Science.gov (United States)

    Weibel, Gisela; Eggenberger, Urs; Kulik, Dmitrii A; Hummel, Wolfgang; Schlumberger, Stefan; Klink, Waldemar; Fisch, Martin; Mäder, Urs K

    2018-03-17

    Fly ash from municipal solid waste incineration contains a large potential for recyclable metals such as Zn, Pb, Cu and Cd. The Swiss Waste Ordinance prescribes the treatment of fly ash and recovery of metals to be implemented by 2021. More than 60% of the fly ash in Switzerland is acid leached according to the FLUWA process, which provides the basis for metal recovery. The investigation and optimization of the FLUWA process is of increasing interest and an industrial solution for direct metal recovery within Switzerland is in development. With this work, a detailed laboratory study on different filter cakes from fly ash leaching using HCl 5% (represents the FLUWA process) and concentrated sodium chloride solution (300 g/L) is described. This two-step leaching of fly ash is an efficient combination for the mobilization of a high percentage of heavy metals from fly ash (Pb, Cd ≥ 90% and Cu, Zn 70-80%). The depletion of these metals is mainly due to a combination of redox reaction and metal-chloride-complex formation. The results indicate a way forward for an improved metal depletion and recovery from fly ash that has potential for application at industrial scale. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Biological Activities of Hominis Placenta Herbal Acupuncture prepared by Hydrochloric Acid Hydrolysis

    Directory of Open Access Journals (Sweden)

    Geun-young Seo

    2010-06-01

    Full Text Available Reactive Oxygen Species(ROS are continuously produced at a high rate as a by-product of aerobic metabolism. Since tissue damage by free radical increases with age, the reactive oxygen species(ROS such as hydrogen peroxide(H2O2, nitric oxide(NO. Several lines of evidence provided that ROS appears to cause to develop aging-related various diseases such as cancer, arthritis, cardiovascular disease. In this study, we have conducted to investigate the biological activities of Hominis Placenta Herbal Acupuncture by measuring total polyphenol content, DPPH radical scavenging, ABTS radical scavenging, Superoxide dismutase(SOD-like activity, Nitrite scavenging ability in vitro. The total polyphenol contents of Hominis Placenta Herbal Acupuncture was 24.6㎖/㎖. Elctron donation ability on DPPH was 49.4%. The 2,2'-azinobis-3-ehtlbezothiazoline-6-sulfonic acid radical decolorization (ABTS was 50.01%, similar to the DPPH free radical scavenging. The superoxide dismutase (SOD-like activities of hominis placenta herbal acupuncture was 50.876%. The nitrite scavenging abilities at pH 1.5, pH 3.0, pH 6.0 were 52.8%, 29.4%, 15.4%, respectively; these abilities decreased as pH increased. We conclude that Hominis Placenta Herbal Acupuncture may be useful as potential sources of antioxidant.

  11. Preservation of urine free catecholamines and their free O-methylated metabolites with citric acid as an alternative to hydrochloric acid for LC-MS/MS-based analyses.

    Science.gov (United States)

    Peitzsch, Mirko; Pelzel, Daniela; Lattke, Peter; Siegert, Gabriele; Eisenhofer, Graeme

    2016-01-01

    Measurements of urinary fractionated metadrenalines provide a useful screening test to diagnose phaeochromocytoma. Stability of these compounds and their parent catecholamines during and after urine collection is crucial to ensure accuracy of the measurements. Stabilisation with hydrochloric acid (HCl) can promote deconjugation of sulphate-conjugated metadrenalines, indicating a need for alternative preservatives. Urine samples with an intrinsically acidic or alkaline pH (5.5-6.9 or 7.1-8.7, respectively) were used to assess stability of free catecholamines and their free O-methylated metabolites over 7 days of room temperature storage. Stabilisation with HCl was compared with ethylenediaminetetraacetic acid/metabisulphite and monobasic citric acid. Catecholamines and metabolites were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Free catecholamines and their O-methylated metabolites were stable in acidic urine samples over 7 days of room temperature storage, independent of the presence or absence of any stabilisation method. In contrast, free catecholamines, but not the free O-methylated metabolites, showed rapid degradation within 24 h and continuing degradation over 7 days in urine samples with an alkaline pH. Adjustment of alkaline urine samples to a pH of 3-5 with HCl or 4.8-5.4 with citric acid completely blocked degradation of catecholamines. Ethylenediaminetetraacetic acid/metabisulphite, although reducing the extent of degradation of catecholamines in alkaline urine, was largely ineffectual as a stabiliser. Citric acid is equally effective as HCl for stabilisation of urinary free catecholamines and minimises hazards associated with use of strong inorganic acids while avoiding deconjugation of sulphate-conjugated metabolites during simultaneous LC-MS/MS measurements of free catecholamines and their free O-methylated metabolites.

  12. The liquid-liquid extraction of chloro-(trichlorostannato)-rhodium(I/III) and -ruthenium (II) complexes from dilute hydrochloric acid into 4-methylpentan-2-one

    International Nuclear Information System (INIS)

    Wyrley-Birch, J.M.

    1984-10-01

    The effect of stannous chloride on the liquid-liquid extraction of rhodium and ruthenium from hydrochloric acid solutions into 4-methyl-pentan-2-one (MIBK)/hexane mixtures was studied in detail. Stannous chloride concentrations were found to considerably increase the efficiency of the extraction of rhodium and ruthenium into the organic phase. Chloro-(trichlorostannato)-rhodium (I/III) complexes were formed at room temperature. The rate of chloro-(trichlorostannato)-ruthenium (II) complex formation was extremely slow at room temperature, but increased on heating of the aqueous solutions. The amount of rhodium and ruthenium extracted into the organic phase depend on the Sn(II):M molar ratio, the HCl, H sup(+) and Cl sup(-) concentrations, as well as the equilibration time. A 119 Sn NMR study of the MIBK extracts, showed that the stoichiometry of the chloro-(trichlorostannato)-rhodium (I/III) complexes extracted into the organic phase was dependent on the Sn(II):Rh(III) molar ratio as well as the HCl, H sup(+) and Cl sup(-) concentrations in the aqueous phase. The predominant species observed in the organic phase from HCl solutions containing Sn(II):Rh(III) ratios >= 5:1, was shown to be an hydrido complex having the form [RhH(SnCl 3 ) 4 Cl] 3 sup(-) or [RhH(SnCl 3 ) 4 ]2 sup(-). An essentially quantitative separation of rhodium and ruthenium was achieved utilising the variation in the rates of rhodium-tin and ruthenium-tin complex formation

  13. Physicochemical and in vitro antioxidant properties of pectin extracted from hot pepper (Capsicum annuum L. var. acuminatum (Fingerh.)) residues with hydrochloric and sulfuric acids.

    Science.gov (United States)

    Xu, Honggao; Tai, Kedong; Wei, Tong; Yuan, Fang; Gao, Yanxiang

    2017-11-01

    Transformation of hot pepper residues to value-added products with concomitant benefits on environmental pollution would be of great value to capsicum oleoresin manufacturers. Pectin, a soluble dietary fiber with multiple functions, from hot pepper residues was investigated in this study. The extraction of hot pepper pectin using hydrochloric acid was first optimized using response surface methodology (RSM). The most efficient parameters for maximum hot pepper pectin yield (14.63%, dry basis) were a pH of 1.0, a temperature of 90 °C, an extraction time of 2 h and a liquid-to-solid ratio of 20 L g -1 . The pectin was mainly composed of uronic acids, and the major neutral sugars were galactose and glucose. The structure of hot pepper pectin was characterized by homogalacturonan and rhamnogalacturonan I elements. The physicochemical properties of hot pepper pectin extracted by sulfuric acid and hydrochloric acid were further investigated. The content of protein and degree of esterification in hot pepper pectin extracted with sulfuric acid solution (SP) were higher (P hot pepper pectin, hot pepper residues would be a new source to obtain pectin, and SP would be more preferred than HP. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  14. Conversion of Levulinic Acid from Various Herbaceous Biomass Species Using Hydrochloric Acid and Effects of Particle Size and Delignification

    Directory of Open Access Journals (Sweden)

    Indra Neel Pulidindi

    2018-03-01

    Full Text Available Acid catalyzed hydrothermal conversion of levulinic acid (LA from various herbaceous materials including rice straw (RS, corn stover (CS, sweet sorghum bagasse (SSB, and Miscanthus (MS was evaluated. With 1 M HCl, 150 °C, 5 h, 20 g/L solid loading, the yields of LA from untreated RS, CS, SSB and MS based on the glucan content were 60.2, 75.1, 78.5 and 61.7 wt %, respectively. It was also found that the particle size had no significant effect on LA conversion yield with >3 h reaction time. With delignification using simulated green liquor (Na2CO3-Na2S, 20 wt % total titratable alkali (TTA, 40 wt % sulfidity at 200 °C for 15 min, lignin removal was in the range of 64.8–91.2 wt %. Removal of both lignin and xylan during delignification increased the glucan contents from 33.0–44.3 of untreated biomass to 61.7–68.4 wt % of treated biomass. Delignified biomass resulted in much lower conversion yield (50.4–56.0 wt % compared to 60.2–78.5 wt % of untreated biomass. Nonetheless, the concentration of LA in the product was enhanced by a factor of ~1.5 with delignification.

  15. Extraction of gold(III) from hydrochloric acid solutions by CTAB/n-heptane/iso-amyl alcohol/Na{sub 2}SO{sub 3} microemulsion

    Energy Technology Data Exchange (ETDEWEB)

    Lu Wenjuan; Lu Yanmin; Liu Fei; Shang Kai; Wang Wei [Key Laboratory for Special Functional Aggregated Materials of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Yang Yanzhao, E-mail: yzhyang@sdu.edu.cn [Key Laboratory for Special Functional Aggregated Materials of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)

    2011-02-28

    The extraction of Au(III) from hydrochloric acid solutions by microemulsion was studied. The extraction experiments were carried out using cetyltrimethylammonium bromide (CTAB) as surfactant and iso-amyl alcohol as co-surfactant. Au(III) was found to be extracted into the microemulsion phase due to ion pair formation such as AuCl{sub 4}{sup -}CTAB{sup +}. The influence of temperature on the extraction of Au(III) has been investigated at temperatures ranging from 288 to 313 K. Temperature was found to decrease the distribution of Au(III). Thermodynamic parameters like enthalpy and entropy of the extraction, calculated by applying Van't Hoff equation, were -36.76 kJ mol{sup -1} and -84.87 J mol{sup -1} K{sup -1}, respectively. Furthermore, the influence of the concentrations of hydrogen ion and chloride anion on the extraction efficiency (E%) were verified. Au(III) was extracted quantitatively (E% > 99%) and selectively at the whole range of HCl concentrations (0.2-5 M). Recovery of gold from electrical waste and treatment of CTAB wastewater generated from the extraction were also discussed. Thus, the extraction of Au(III) from hydrochloric acid solutions by microemulsion is an effective approach.

  16. Ion exchange separation of carrier-free 140Ba and 140La from their equilibrium mixture using nitrilotriacetic acid and ascorbic acid as eluents

    International Nuclear Information System (INIS)

    Das, N.R.; Bhattacharyya, S.N.

    1982-01-01

    A simple cation exchange procedure for separation of 140 Ba- 140 La using Dowex 50W-X8 and nitrilotriacetic acid or ascorbic acid as the eluent has been described. The optimal separation of the daughter from the parent has been achieved using a 4% Na-nitrilotriacetate or Na-ascorbate solution at pH 7. The parent, 140 Ba, left in the column can be eluted with dilute hydrochloric acid or it can be retained in the column for milking off the daughter, 140 La, when needed. The radiochemical purity of the separated isotopes, 140 Ba and 140 La, were verified by γ-ray spectrometry. (author)

  17. Extraction of Sm(IIIand Nd(III with N,N,N’,N’-tetrabutyl-3-oxy-diglycolamidefrom hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Yang J.H.

    2013-01-01

    Full Text Available The extraction behavior of Sm(III and Nd(III with N,N,N’,N’-tetrabutyl-3-oxa-diglycolamide (TBDGA in 70% kerosene-30% n-octanol from hydrochloride acid wasstudied. The effect of hydrochloric acid concentration, extractant concentration,and temperature on the distribution of rare earth elementswas investigated. The extraction mechanism was established and the stoichiometry of the main extracted species was confirm to be SmCl3•2TBDGA and NdCl3•2TBDGA for Sm(III and Nd(III, respectively. The extraction distribution ratio decreases with an increase in temperature, which demonstrates that the extraction reaction is exothermic. The IR spectra of the loaded organic phase and free extractant were recorded and discussed.

  18. Alginate biopolymer as green corrosion inhibitor for copper in 1 M hydrochloric acid: Experimental and theoretical approaches

    Science.gov (United States)

    Jmiai, A.; El Ibrahimi, B.; Tara, A.; El Issami, S.; Jbara, O.; Bazzi, L.

    2018-04-01

    The anti-corrosion behavior of sodium alginate (SA) on copper in the 1 M hydrochloric medium was carried out using weight loss and electrochemical measurements. The obtained results show that the inhibition increases with SA concentration and then reaches a maximum of 83% at a concentration of 0.1 mg L-1. The effect of temperature on the reactions of copper corrosion inhibition and analyzing the thermodynamic parameters revealed that the mode of adsorption has a physical nature and obeys the Langmuir isotherm. The surface morphology was performed by scanning electron microscopy coupled with energy dispersive X-ray spectrometry and atomic force microscopy. To better understand the adsorption mechanism, describing the relationship between inhibitory ability and the molecular structure of SA, quantum calculations using density functional theory were performed. Monte Carlo simulation approache was performed to know well of the relationship between the inhibition ability and molecular structure of alginate.

  19. Electrochemical measurements for the corrosion inhibition of mild steel in 1 M hydrochloric acid by using an aromatic hydrazide derivative

    Directory of Open Access Journals (Sweden)

    P. Preethi Kumari

    2017-07-01

    Full Text Available The influence of an aromatic hydrazide derivative, 2-(3,4,5-trimethoxybenzylidene hydrazinecarbothioamide (TMBHC as corrosion inhibitor on mild steel in 1 M hydrochloric acid was studied by Tafel polarization and electrochemical impedance spectroscopy (EIS technique. The results showed that the inhibition efficiency (% IE of TMBHC increased with increasing inhibitor concentrations and also with increase in temperatures. TMBHC acted as a mixed type of inhibitor and its adsorption on mild steel surface was found to follow Langmuir’s adsorption isotherm. The evaluation of thermodynamic and activation parameters indicated that the adsorption of TMBHC takes place through chemisorption. The formation of protective film was further confirmed by scanning electron microscopy (SEM.

  20. Separation of uranium and other metals from commercial phosphoric acid by ion-exchange and voltammetric determination of uranium

    International Nuclear Information System (INIS)

    Ferreira, J.B.C.; Carvalho, F.M.S. de; Abrao, A.

    1985-11-01

    The separation of metals from crude commercial phosphoric acid is achieved by simple dilution and percolation through a strong cationic ion exchanger. Uranium, calcium, magnesium, manganese, iron and aluminum are quantitatively fixed by the exchanger and can be detected or analysed after their complete elution with 6 M HCI. Titanium and zirconium are only partially retained. Specially for its separation and determination uranium is retained selectively by the resin from the phosphoric acid-EDTA solution, the column is washed with water and then eluted with hydrochloric acid. Uranium is analyzed by voltametry with the hanging drop mercury electrode. (Author) [pt

  1. Hydrothermal synthesis of highly crystalline RuS2 nanoparticles as cathodic catalysts in the methanol fuel cell and hydrochloric acid electrolysis

    International Nuclear Information System (INIS)

    Li, Yanjuan; Li, Nan; Yanagisawa, Kazumichi; Li, Xiaotian; Yan, Xiao

    2015-01-01

    Highlights: • Highly crystalline RuS 2 nanoparticles have been first synthesized by a “one-step” hydrothermal method. • The product presents a pure cubic phase of stoichiometric ratio RuS 2 with average particle size of 14.8 nm. • RuS 2 nanoparticles were used as cathodic catalysts in methanol fuel cell and hydrochloric acid electrolysis. • The catalyst outperforms commercial Pt/C in methanol tolerance and stability towards Cl − . - Abstract: Highly crystalline ruthenium sulfide (RuS 2 ) nanoparticles have been first synthesized by a “one-step” hydrothermal method at 400 °C, using ruthenium chloride and thiourea as reactants. The products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy/energy disperse spectroscopy (SEM/EDS), thermo gravimetric-differential thermal analyze (TG-DTA), transmission electron microscopy equipped with selected area electron diffraction (TEM/SAED). Fourier transform infrared spectra (IR), and X-ray photoelectron spectroscopy (XPS). XRD result illustrates that the highly crystalline product presents a pure cubic phase of stoichiometric ratio RuS 2 and the average particle size is 14.8 nm. SEM and TEM images display the products have irregular shape of 6–25 nm. XPS analyst indicates that the sulfur exists in the form of S 2 2− . Cyclic voltammetry (CV), rotating disk electrode (RDE), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) measurements are conducted to evaluate the electrocatalytic activity and stability of the highly crystalline RuS 2 nanoparticles in oxygen reduction reaction (ORR) for methanol fuel cell and hydrochloric acid electrolysis. The results illustrate that RuS 2 is active towards oxygen reduction reaction. Although the activity of RuS 2 is lower than that of Pt/C, the RuS 2 catalyst outperforms commercial Pt/C in methanol tolerance and stability towards Cl −

  2. Characterization of the Unusual Product from the Reaction between Cobalt(II) Chloride, Ethane-1,2-diamine, and Hydrochloric Acid: An Undergraduate Project Involving an Unknown Metal Complex.

    Science.gov (United States)

    Curtis, Neil F.; And Others

    1986-01-01

    Discusses the need for student research-type chemistry projects based upon "unknown" metal complexes. Describes an experiment involving the product from the reaction between cobalt(II) chloride, ethane-1,2-diamine (en) and concentrated hydrochloric acid. Outlines the preparation of the cobalt complex, along with procedure, results and…

  3. Molecular and crystal structures of the products of crystallization of (N'-furfurylidene)isonicotinoylhydrazide from aqueous solutions of hydrochloric and acetic acids

    International Nuclear Information System (INIS)

    Chuev, I.I.; Nikonova, L.A.; Atovmyan, E.G.; Utenyshev, A.N.; Aldoshin, S.M.

    2001-01-01

    Crystals of (N ' -furfurylidene)isonicotinoylhydrazide (I), which have been isolated from a water-methanol solution of hydrochloric acid (Ia) and an aqueous solution (∼50%) of acetic acid (Ib), are studied by X-ray diffraction. In Ia, the nitrogen atom of the pyridine ring is protonated. In the crystal, the intermolecular C=O···HN(Py) hydrogen bonds link the I · H + cations into chains which are bound through centrosymmetric NH···W···Cl - ···W ' ···H ' N ' bridges. In molecule Ib, no protonation occurs; however, its pyridine N atom is blocked by the hydroxyl H atom of a solvate molecule of acetic acid. Crystals Ib have a layered structure. The crystallization water molecule is involved in the formation of three intermolecular hydrogen bonds, namely, those with the H atom of the amide group and the carbonyl O atoms of molecule I and an acetic acid molecule of the neighboring layer

  4. Plutonium and americium separation from salts

    International Nuclear Information System (INIS)

    Hagan, P.G.; Miner, F.J.

    1976-01-01

    Salts or materials containing plutonium and americium are dissolved in hydrochloric acid, heated, and contacted with an alkali metal carbonate solution to precipitate plutonium and americium carbonates which are thereafter readily separable from the solution

  5. Preliminary Study on the Kinetics and Mechanism of the Oxidation of Naphthol Green B by Dichromate Ion in Aqueous Hydrochloric Acid Medium

    Directory of Open Access Journals (Sweden)

    Bako Myek

    2014-04-01

    Full Text Available The kinetics of the oxidation of naphthol green B (NGB3- by Cr2O7 2- has been studied in aqueous hydrochloric acid medium at an ionic strength, I = 0.50 mol dm-3 (NaCl, H+ =1.0  10-4 mol dm-3 (HCl and T = 25  1C. The redox reaction displayed a stoichiometry of 1:1 and obeys the rate law: -dNGB3-/dt = k2NGB3-]Cr2O7 2- . The second order rate constant increases with increase in acid concentration and in the ionic strength of reaction medium. The rates of reaction displayed a positive salt effect. Addition of acrylonitrile to a partially reacted mixture in the presence of excess methanol did not lead to gel formation. Added cations and anions inhibited the naphthol green B - Cr2O7 2- reaction. Results of the Michaelis – Menten plot gave no evidence of intermediate complex formation during the course of the reaction. Based on the results obtained, the reaction is believed to proceed through the outersphere mechanistic pathway.

  6. Hydrothermal synthesis of highly crystalline RuS{sub 2} nanoparticles as cathodic catalysts in the methanol fuel cell and hydrochloric acid electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yanjuan [Key Laboratory of Marine Chemistry Theory and Technology, Minisry of Education Ocean University of China, Qingdao, 266100 (China); College of Material Science and Engineering, Key Laboratory of Automobile Materials of Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Li, Nan, E-mail: lin@jlu.edu.cn [College of Material Science and Engineering, Key Laboratory of Automobile Materials of Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Yanagisawa, Kazumichi [Research Laboratory of Hydrothermal Chemistry, Kochi University, Kochi 780-8520 (Japan); Li, Xiaotian [College of Material Science and Engineering, Key Laboratory of Automobile Materials of Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Yan, Xiao [Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012 (China)

    2015-05-15

    Highlights: • Highly crystalline RuS{sub 2} nanoparticles have been first synthesized by a “one-step” hydrothermal method. • The product presents a pure cubic phase of stoichiometric ratio RuS{sub 2} with average particle size of 14.8 nm. • RuS{sub 2} nanoparticles were used as cathodic catalysts in methanol fuel cell and hydrochloric acid electrolysis. • The catalyst outperforms commercial Pt/C in methanol tolerance and stability towards Cl{sup −}. - Abstract: Highly crystalline ruthenium sulfide (RuS{sub 2}) nanoparticles have been first synthesized by a “one-step” hydrothermal method at 400 °C, using ruthenium chloride and thiourea as reactants. The products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy/energy disperse spectroscopy (SEM/EDS), thermo gravimetric-differential thermal analyze (TG-DTA), transmission electron microscopy equipped with selected area electron diffraction (TEM/SAED). Fourier transform infrared spectra (IR), and X-ray photoelectron spectroscopy (XPS). XRD result illustrates that the highly crystalline product presents a pure cubic phase of stoichiometric ratio RuS{sub 2} and the average particle size is 14.8 nm. SEM and TEM images display the products have irregular shape of 6–25 nm. XPS analyst indicates that the sulfur exists in the form of S{sub 2}{sup 2−}. Cyclic voltammetry (CV), rotating disk electrode (RDE), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) measurements are conducted to evaluate the electrocatalytic activity and stability of the highly crystalline RuS{sub 2} nanoparticles in oxygen reduction reaction (ORR) for methanol fuel cell and hydrochloric acid electrolysis. The results illustrate that RuS{sub 2} is active towards oxygen reduction reaction. Although the activity of RuS{sub 2} is lower than that of Pt/C, the RuS{sub 2} catalyst outperforms commercial Pt/C in methanol tolerance and stability towards Cl{sup −}.

  7. Physicochemical aspects of decomposition of silica-alumina ores of argillites and green clays of Chashma-Sang Deposit of the Republic of Tajikistan by hydrochloric and nitric acids

    International Nuclear Information System (INIS)

    Kayumov, A.M.

    2018-01-01

    The purpose of work is to study the processes of decomposition of silica-alumina ores of argillites and green clays of Chashma-Sang Deposit of the Republic of Tajikistan by hydrochloric and nitric acids in temperature interval 20-98 deg C with the using of methods of selective extraction of valuable materials; elaboration of rational conditions of decomposition of raw material. Physicochemical properties of initial aluminium comprising ores, intermediate and final products of processing of argillites and green clays have been studied. Kinetic parameters of processes at acidic decomposition of argillites and green clays have been studied as well. The kinetic parameters of processes of decomposition of green clays and argillites by nitric and hydrochloric acids have been calculated. The flowsheet of complex processing of green clays and argillites of Chashma-Sang Deposit has been elaborated.

  8. Studies on rapid ion-exchange separation of the transplutonium elements with mineral acid-methanol mixed media

    International Nuclear Information System (INIS)

    Usuda, Shigekazu

    1989-03-01

    In order to study properties of short-lived transplutonium nuclides synthesized by heavy-ion bombardment, three methods for rapid separation of tri-valent transplutonium elements by ion-exchange chromatography with mineral acid-methanol mixed media at elevated temperature were investigated. The first separation method was anion-exchange chromatography with nitric acid-methanol mixed media. The second method was anion-exchange choromatography with dilute hydrochloric acid-methanol mixed media. The third method was improved cation-exchange chromatography with single-column operation using the mixed media of hydrochloric acid and methanol. The separation methods developed were found applicable to studies on synthesis of the trans-plutonium nuclides, 250 Fm (T 1/2 :30 min), 244,245,246 Cf (T 1/2 :20 min, 46 min and 35.7 h, respectively) from the 16 O + 238 U and 12 C + 242 Pu reactions, and on the decay property of 245 Cf. Attempts to search for new actinide nuclides, such as 240 U and neutron deficient nuclides of Am, Cm and Bk, were made by a quick purification. The separation system was also applied to the rapid and effective separation of Nd, Am and Cm from spent nuclear fuel samples, for burn-up determination. (J.P.N.) 242 refs

  9. 40 CFR 63.1218 - What are the standards for hydrochloric acid production furnaces that burn hazardous waste?

    Science.gov (United States)

    2010-07-01

    ... acid production furnaces that burn hazardous waste? 63.1218 Section 63.1218 Protection of Environment... production furnaces that burn hazardous waste? (a) Emission limits for existing sources. You must not...% DRE. If you burn the dioxin-listed hazardous wastes F020, F021, F022, F023, F026, or F027 (see § 261...

  10. Porous media investigation before and after hydrochloric acid injection on a pre-salt carbonate coquinas sample.

    Science.gov (United States)

    Machado, A C; Teles, A P; Pepin, A; Bize-Forest, N; Lima, I; Lopes, R T

    2016-04-01

    Porous space characterization of carbonate rocks is an important aid in petroleum exploration from carbonate reservoir. In this study, X-ray microtomography technique was applied to evaluate total porosity of a coquina sample extracted from pre-salt reservoir, in Brazil, before and after acid injection. Two image processing program were used in order to assess performance. The results showed that microtomography has potential to compute porosity of coquina samples and provides information about rock porous network. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Xanthium strumarium leaves extracts as a friendly corrosion inhibitor of low carbon steel in hydrochloric acid: Kinetics and mathematical studies

    Directory of Open Access Journals (Sweden)

    Anees A. Khadom

    2018-06-01

    Full Text Available Corrosion inhibition of low carbon steel in 1 M HCl was investigated in absence and presence of Xanthium strumarium leaves (XSL extracts as a friendly corrosion inhibitor. The effect of temperature and inhibitor concentration was studied using weight loss method. The result obtained shown that Xanthium strumarium leaves extracts act as an inhibitor for low carbon steel in HCl and reduces the corrosion rate. The inhibition efficiency was found to increases with increase in inhibitor concentration and temperature. Higher inhibition efficiency was 94.82% at higher level of inhibitor concentration and temperature. The adsorption of Xanthium strumarium leaves extracts was found to obey Langmuir adsorption isotherm model. The values of the free energy of adsorption was more than −20 kJ/mol, which is indicative of mixed mode of physical and chemical adsorption. Keywords: Corrosion, Green inhibitor, Natural extracts, Low carbon steel, Acid, Adsorption

  12. Inhibition of the corrosion of steel in hydrochloric acid solution by some organic molecules containing the methylthiophenyl moiety

    International Nuclear Information System (INIS)

    Nataraja, S.E.; Venkatesha, T.V.; Manjunatha, K.; Poojary, Boja; Pavithra, M.K.; Tandon, H.C.

    2011-01-01

    Highlights: → Acid corrosion inhibition. → Work in small concentration. → Effective at higher temperature. → Effect of different functional groups, cyclisation and aromaticity. - Abstract: The corrosion inhibition effect of 2-[4-(methylthio) phenyl] acetohydrazide (HYD), 2-{[4-(methylthio) phenyl] acetyl} hydrazinecarbothioamide (TAD) and 5-[4-(methylthio) benzyl]-4H-1,2,4-triazole-3-thiol (TRD) on steel in 1.0 M HCl was investigated by mass loss and electrochemical methods. The effect of concentration, temperature and immersion time was studied. The results indicated that the compounds are efficient, mixed type and pursue Flory-Huggins adsorption isotherm. The inhibition efficiency at lower concentration of inhibitor decreased with temperature while at higher concentration, it is retained and the calculated free energy attributes this to comprehensive adsorption. The efficiency stands in the order TRD > TAD > HYD and is confirmed by the Quantum studies.

  13. Rapid ion-exchange separations of actinides

    International Nuclear Information System (INIS)

    Usuda, Shigekazu

    1988-01-01

    For the purpose of studying short-lived actinide nuclides, three methods for rapid ion exchange separation of actinide elements with mineral acid-alcohol mixed media were developed: anion exchange with nitric acid-methyl alcohol mixed media to separate the transplutonium and rare earth elements from target material, U or Pu and Al catcher foils; anion exchange with hydrochloric acid-methyl alcohol media to separate Am+Cm, Bk and Cf+Fm from the target, catcher foils and major fission products; and cation exchange with hydrochloric acid-methyl alcohol media and with concentrated hydrochloric acid to separate the transplutonium elements as a group from the rare earths after eliminating the large amounts of U, Al, Cu, Fe etc. The methods enable one to perform rapid and effective separation at elevated temperature (90 deg C) and immediate source preparation for alpha-ray spectrometry. (author) 47 refs.; 10 figs

  14. The effect of alloyed nitrogen or dissolved nitrate ions on the anodic behaviour of austenitic stainless steel in hydrochloric acid

    International Nuclear Information System (INIS)

    Shahrabi, T.

    2004-01-01

    The anodic behaviour of high purity stainless steels, based on a 316L composition, has been studied at room temperature in HCl solutions from 1 to 6 M. For all acid concentrations, the presence of 0.22% nitrogen has little or no effect on the active dissolution kinetics at low over-potentials. The effect on the critical current density for passivation is also small for low HCl concentrations ( 4.5 M), no passivation occurs and again nitrogen has little effect. However, for HCl concentrations around 4 M nitrogen reversibly impedes active dissolution at a few hundred mA cm -2 . The effect does not appear to be an oxide passivation, but is more likely to be due to surface enrichment of nitrogen atoms. Implications for localized corrosion are discussed. An effect similar to that of nitrogen alloying is reproduced on a nitrogen free alloy by adding 2 M NaNO 3 to a 4M HCl solution. This effect is distinct from the passivation of salt-covered surfaces and may be preferable to the latter as an explanation of the increase in pitting potential by nitrate additions to NaCl solutions. Passivation under a salt film is retained to explain the passivation of growing pits above the inhibition potential. (authors)

  15. Ex Vivo Liver Experiment of Hydrochloric Acid-Infused and Saline-Infused Monopolar Radiofrequency Ablation: Better Outcomes in Temperature, Energy, and Coagulation

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Xiong-ying; Gu, Yang-kui; Huang, Jin-hua, E-mail: huangjh@sysucc.org.cn; Gao, Fei; Zou, Ru-hai; Zhang, Tian-qi [Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China (China)

    2016-04-15

    ObjectiveTo compare temperature, energy, and coagulation between hydrochloric acid-infused radiofrequency ablation (HAIRFA) and normal saline-infused radiofrequency ablation (NSIRFA) in ex vivo porcine liver model.Materials and Methods30 fresh porcine livers were excised in 60 lesions, 30 with HAIRFA and the other 30 with NSIRFA. Both modalities used monopolar perfusion electrode connected to a RF generator set at 103 °C and 30 W. In each group, ablation time was set at 10, 20, or 30 min (10 lesions from each group at each time). We compared tissue temperatures (at 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 cm away from the electrode tip), average power, deposited energy, deposited energy per coagulation volume (DEV), coagulation diameters, coagulative volume, and spherical ratio between the two groups.ResultsTemperature–time curves showed that HAIRFA provided progressively greater heating than that of NSIRFA. At 30 min, mean average power, deposited energy, coagulation volumes (113.67 vs. 12.28 cm{sup 3}) and diameters, and increasing in tissue temperature were much greater with HAIRFA (P < 0.001 for all), except DEV was lower (456 vs. 1396 J/cm{sup 3}, P < 0.001). The spherical ratio was closer to 1 with HAIRFA (1.23 vs. 1.46). Coagulation diameters, volume, and average power of HAIRFA increased significantly with longer ablation times. While with NSIRFA, these characteristics were stable till later 20 min, except the power decreased with longer ablation times.ConclusionsHAIRFA creates much larger and more spherical lesions by increasing overall energy deposition, modulating thermal conductivity, and transferring heat during ablation.

  16. Effects of chopping, and soaking in water, hydrochloric acidic and calcium hydroxide solutions on the nutritional value of Acacia villosa for goats

    International Nuclear Information System (INIS)

    Wina, E.; Tangendjaja, B.; Susana, I.W.R.

    2005-01-01

    Acacia villosa, a thornless shrub legume, has potential as a feed supplement for ruminants if anti-nutritional factors, especially tannins, can be overcome. The effects of chopping and soaking the leaves on the amounts of tannin in the extracting solution and that left in the recovered leaves were studied. The tannin and non-tannin phenolics were solubilized in the extracting solution and the amount was increased with the soaking time. Soaking in calcium hydroxide solution, hydrochloric acid or water removed 41-76% of tannin and total phenolics removed from the recovered leaves. Soaking of the leaves also removed fermentable materials and reduced the gas production. In the first of two digestibility experiments, three groups of goats received one of these diets, those were: (1) sugar cane tops: unsoaked Acacia leaves (7:3), (2) sugar cane tops: water soaked Acacia leaves (7:3) and (3) sugar cane tops: water soaked Acacia leaves (7:3) + 100 g/day of cassava flour. Live weight of goats was measured every 2 weeks and a large increase in average daily gain was obtained for goats fed diet containing water soaked leaves and cassava flour (71 g/day) compared to those fed diet containing unsoaked leaves and water soaked leaves (38.9 and 44.7 g/day, respectively) (P 0.05) found in intake or digestibility between unsoaked and soaked leaves. In conclusion, soaking reduced tannin in Acacia leaves, improved digestibility and intake of Acacia leaves. In the presence of cassava flour, soaking improved average daily gain. Diets supplemented with water soaked Acacia leaves probably also need an energy supplement and cassava flour is one of the feed ingredients that is satisfactory. (author)

  17. Effects of chopping, and soaking in water, hydrochloric acidic and calcium hydroxide solutions on the nutritional value of Acacia villosa for goats

    Energy Technology Data Exchange (ETDEWEB)

    Wina, E. [Research Institute for Animal Production, Bogor (Indonesia)]. E-mail: winabudi@yahoo.com; Tangendjaja, B.; Susana, I.W.R. [Research Institute for Animal Production, Bogor (Indonesia)

    2005-08-19

    Acacia villosa, a thornless shrub legume, has potential as a feed supplement for ruminants if anti-nutritional factors, especially tannins, can be overcome. The effects of chopping and soaking the leaves on the amounts of tannin in the extracting solution and that left in the recovered leaves were studied. The tannin and non-tannin phenolics were solubilized in the extracting solution and the amount was increased with the soaking time. Soaking in calcium hydroxide solution, hydrochloric acid or water removed 41-76% of tannin and total phenolics removed from the recovered leaves. Soaking of the leaves also removed fermentable materials and reduced the gas production. In the first of two digestibility experiments, three groups of goats received one of these diets, those were: (1) sugar cane tops: unsoaked Acacia leaves (7:3), (2) sugar cane tops: water soaked Acacia leaves (7:3) and (3) sugar cane tops: water soaked Acacia leaves (7:3) + 100 g/day of cassava flour. Live weight of goats was measured every 2 weeks and a large increase in average daily gain was obtained for goats fed diet containing water soaked leaves and cassava flour (71 g/day) compared to those fed diet containing unsoaked leaves and water soaked leaves (38.9 and 44.7 g/day, respectively) (P < 0.05). In the second digestibility experiment, the three diets were: (1) sugar cane tops: unsoaked Acacia (7:3), (2) sugar cane tops water soaked Acacia (7:3), (3) sugar cane tops: calcium hydroxide soaked Acacia (7:3). A supplement of 100 g/day of cassava flour was added to each of these three diets. In both digestibility experiments, soaking improved intake and digestibility of Acacia leaves, and cassava flour increased the intake, but when all the diets contained cassava flour, there was no significant difference (P > 0.05) found in intake or digestibility between unsoaked and soaked leaves. In conclusion, soaking reduced tannin in Acacia leaves, improved digestibility and intake of Acacia leaves. In the

  18. Effect of a low-viscosity adhesive resin on the adhesion of metal brackets to enamel etched with hydrochloric or phosphoric acid combined with conventional adhesives.

    Science.gov (United States)

    Yetkiner, Enver; Ozcan, Mutlu; Wegehaupt, Florian Just; Wiegand, Annette; Eden, Ece; Attin, Thomas

    2013-12-01

    This study investigated the effect of a low-viscosity adhesive resin (Icon) applied after either hydrochloric (HCl) or phosphoric acid (H3PO4) on the adhesion of metal brackets to enamel. Failure types were analyzed. The crowns of bovine incisors (N = 20) were sectioned mesio-distally and inciso-gingivally, then randomly assigned to 4 groups according to the following protocols to receive mandibular incisor brackets: 1) H3PO4 (37%)+TransbondXT (3M UNITEK); 2) H3PO4 (37%)+Icon+TransbondXT; 3) HCl (15%)+Icon (DMG)+TransbondXT 4) HCl (15%)+Icon+Heliobond (Ivoclar Vivadent)+TransbondXT. Specimens were stored in distilled water at 37°C for 24 h and thermocycled (5000x, 5°C to 55°C). The shear bond strength (SBS) test was performed using a universal testing machine (1 mm/min). Failure types were classified according to the Adhesive Remnant Index (ARI). Contact angles of adhesive resins were measured (n = 5 per adhesive) on ceramic surfaces. No significant difference in SBS was observed, implying no difference between combinations of adhesive resins and etching agents (p = 0.712; ANOVA). The Weibull distribution presented significantly lower Weibull modulus (m) of group 3 (m = 2.97) compared to other groups (m = 5.2 to 6.6) (p group 1 (45.4 ± 7.9) > group 2 (44.2 ± 10.6) > group 3 (42.6 ± 15.5). While in groups 1, 3, and 4 exclusively an ARI score of 0 (no adhesive left on tooth) was observed, in group 2, only one specimen demonstrated score 1 (less than half of adhesive left on tooth). Contact angle measurements were as follows: Icon (25.86 ± 3.81 degrees), Heliobond (31.98 ± 3.17 degrees), TransbondXT (35 ± 2.21 degrees). Icon can be safely used with the conventional adhesives tested on surfaces etched with either HCl or H3PO4.

  19. Investigation of rare earths sorption from sulfuric- and hydrochloric media

    International Nuclear Information System (INIS)

    Nikonov, V.N.; Mikhlin, E.B.; Norina, T.M.; Afonina, T.A.

    1978-01-01

    A rate of equilibrium attainment has been studied during REE sorption from sulfuric and hydrochloric acid solutions and pulps. It has been shown that equilibrium upon sorption from hydrochloric acid solutions is attained faster than from sulfuric acid solutions. Equilibrium upon sorption from pulps is attained considerably slower than upon sorption from solutions. In all cases REM of cerium subgroup are sorbed better. An effect has been studied of the medium acidity on sorbability of REM and elements of iron and calcium impurities. It has been established that sorbability of these elements decreases with increasing acid concentration. Selectivity of REM sorption from sulfuric acid solutions decreases with a rise in H 2 SO 4 concentration in the solution. For hydrochloric acid solutions it remains constant in a wide range of HCl concentrations. Sorption leaching of REM from concentrates and cakes of sulfuric and hydrochloric acids in the presence of KU-2 leads to high technical and economic indexes: extraction with respect to the total amount of REM and yttrium into a commercial product is 76-86% for sulfuric acid solutions and 81-90% for hydrochloric solutions

  20. The sorption of acids in cellular side of apple pressing

    International Nuclear Information System (INIS)

    Asoev, M.G.; Mukhiddinov, Z.K.

    1994-01-01

    Equilibrium swell of sample refuse after separation of water is use for study of sorption of hydrochloric acid. Quantity adsorb acids set a price to difference her concentration before and after equilibrium sorption

  1. Investigation of adsorption and inhibitive effect of acid red GRE (183 dye on the corrosion of carbon steel in hydrochloric acid media

    Directory of Open Access Journals (Sweden)

    M. Abd El-raouf

    2015-09-01

    Full Text Available The adsorption and corrosion inhibitive effect of acid red GRE (183 dye on carbon steel alloy in 1 M HCl solutions was studied using various techniques. Results of weight loss, Tafel polarization measurements and electrochemical impedance spectroscopy (EIS techniques show that this compound has fairly good inhibiting properties for steel corrosion in acidic bath; with efficiency around 96% at a concentration of 50 ppm. The inhibition is of a mixed anodic–cathodic nature. Factors affecting the corrosion process have been calculated and discussed. Acid red GRE (183 dye was shown to be an inhibitor in the acidic corrosion. Inhibition efficiency increased with acid red GRE (183 dye concentration but decreased with rise in temperature, corrosion inhibition is attributed to the adsorption of acid red GRE (183 dye on the carbon steel surface via a physical adsorption mechanism. Langmuir isotherm is found to provide an accurate description of the adsorption behavior of the investigated azo compound. The nature of the protective film was investigated using SEM and EDX techniques.

  2. Influence of several nonferrous metals in the treatment of residual liquors from hydrochloric acid pickling processes. Influencia de diversos metales no ferreos en el tratamiento de lejias residuales de decapado con acido clorhidrico

    Energy Technology Data Exchange (ETDEWEB)

    Negro, C.; Cobos, M.A.; Latorre, R.; Dufour, J.; Formoso, A.; Lopez, F.

    1994-01-01

    In the oxiprecipitation of waste liquors from siderurgical processes of pickling with hydrochloric acid, several kinds of iron oxides and oxihydroxides are obtained: alpha-FeOOH, gamma-FeOOH, Fe[sub 3]O[sub 4], gamma-Fe[sub 2]O[sub 3]. Fe[sub 2]O[sub 3].1,2H[sub 2]O, etc. These products can be used like pigments in the painting industry and like raw materials for the obtaining of ferrites. Varying the operation conditions, the presence of these products can be changed greatly, obtaining different mixtures of them. The presence of non-ferrous metals catalyzes and modifies the mechanism of the reaction, yielding pure products. This simplifies their later industrial applications. The aim of this work is to determine the influence of Cu(II), Zn(II), Mo(VI) and Al(III) on the oxiprecipitation of residual liquors from hydrochloric acid pickling processes, selecting the most favourable operation conditions at which it is possible to obtain products for industrial applications.

  3. Study of Temperature Effect on the Corrosion Inhibition of C38 Carbon Steel Using Amino-tris(Methylenephosphonic Acid in Hydrochloric Acid Solution

    Directory of Open Access Journals (Sweden)

    Najoua Labjar

    2011-01-01

    Full Text Available Tafel polarization method was used to assess the corrosion inhibitive and adsorption behaviours of amino-tris(methylenephosphonic acid (ATMP for C38 carbon steel in 1 M HCl solution in the temperature range from 30 to 60∘C. It was shown that the corrosion inhibition efficiency was found to increase with increase in ATMP concentration but decreased with temperature, which is suggestive of physical adsorption mechanism. The adsorption of the ATMP onto the C38 steel surface was found to follow Langmuir adsorption isotherm model. The corrosion inhibition mechanism was further corroborated by the values of kinetic and thermodynamic parameters obtained from the experimental data.

  4. Alteration of the phospho- or neutral lipid content and fatty acid composition in Listeria monocytogenes due to acid adaptation mechanisms for hydrochloric, acetic and lactic acids at pH 5.5 or benzoic acid at neutral pH.

    Science.gov (United States)

    Mastronicolis, Sofia K; Berberi, Anita; Diakogiannis, Ioannis; Petrova, Evanthia; Kiaki, Irene; Baltzi, Triantafillia; Xenikakis, Polydoros

    2010-10-01

    This study provides a first approach to observe the effects on Listeria monocytogenes of cellular exposure to acid stress at low or neutral pH, notably how phospho- or neutral lipids are involved in this mechanism, besides the fatty acid profile alteration. A thorough investigation of the composition of polar and neutral lipids from L. monocytogenes grown at pH 5.5 in presence of hydrochloric, acetic and lactic acids, or at neutral pH 7.3 in presence of benzoic acid, is described relative to cells grown in acid-free medium. The results showed that only low pH values enhance the antimicrobial activity of an acid. We suggest that, irrespective of pH, the acid adaptation response will lead to a similar alteration in fatty acid composition [decreasing the ratio of branched chain/saturated straight fatty acids of total lipids], mainly originating from the neutral lipid class of adapted cultures. Acid adaptation in L. monocytogenes was correlated with a decrease in total lipid phosphorus and, with the exception of cells adapted to benzoic acid, this change in the amount of phosphorus reflected a higher content of the neutral lipid class. Upon acetic or benzoic acid stress the lipid phosphorus proportion was analysed in the main phospholipids present: cardiolipin, phosphatidylglycerol, phosphoaminolipid and phosphatidylinositol. Interestingly only benzoic acid had a dramatic effect on the relative quantities of these four phospholipids.

  5. Liquid-liquid extraction/separation of platinum(IV) and rhodium(III) from acidic chloride solutions using tri-iso-octylamine

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jin-Young, E-mail: jinlee@kigam.re.kr [Metals Recovery Department, Minerals Resources Research Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), 92 Gahangno, Yuesong-gu, Daejeon 305-350 (Korea, Republic of); Rajesh Kumar, J., E-mail: rajeshkumarphd@rediffmail.com [Metals Recovery Department, Minerals Resources Research Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), 92 Gahangno, Yuesong-gu, Daejeon 305-350 (Korea, Republic of); Kim, Joon-Soo; Park, Hyung-Kyu; Yoon, Ho-Sung [Metals Recovery Department, Minerals Resources Research Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), 92 Gahangno, Yuesong-gu, Daejeon 305-350 (Korea, Republic of)

    2009-08-30

    Liquid-liquid extraction/separation of platinum(IV) and rhodium(III) from acidic chloride solutions was carried out using tri-iso-octylamine (Alamine 308) as an extractant diluted in kerosene. The percentage extraction of platinum(IV) and rhodium(III) increased with increase in acid concentration up to 8 mol L{sup -1}. However, at 10 mol L{sup -1} HCl concentration, the extraction behavior was reversed, indicating the solvation type mechanism during extraction. The quantitative extraction of {approx}98% platinum(IV) and 36% rhodium(III) was achieved with 0.01 mol L{sup -1} Alamine 308. The highest separation factor (S.F. = 184.7) of platinum(IV) and rhodium(III) was achieved with 0.01 mol L{sup -1} Alamine 308 at 1.0 mol L{sup -1} of hydrochloric acid concentration. Alkaline metal salts like sodium chloride, sodium nitrate, sodium thiocyanate, lithium chloride, lithium nitrate, potassium chloride and potassium thiocyanate used for the salting-out effect. LiCl proved as best salt for the extraction of platinum(IV). Temperature effect demonstrates that the extraction process is exothermic. Hydrochloric acid and thiourea mixture proved to be better stripping reagents when compared with other mineral acids and bases.

  6. Inhibitor efficiency in long-time protection of steel tanks for the chemical surface preparation against local corrosion by process solutions containing hydrochloric acid; Inhibitorwirksamkeit beim Langzeitschutz von Stahlbehaeltern fuer die chemische Oberflaechenvorbereitung gegen oertliche Korrosion durch salzsaeurehaltige Prozessloesungen

    Energy Technology Data Exchange (ETDEWEB)

    Stieglitz, U.; Schulz, W.D. [Institut fuer Korrosionsschutz Dresden GmbH, Gostritzer Str. 61-63, D-01217 Dresden (Germany)

    2004-02-01

    The efficiency of prevailing acid inhibitors is examined by age hardening heavy tank-steel plates in technically usual hot-galvanizing solutions for 1000 hours. With acid inhibitors local corrosion emerged as shallow pit formation first and foremost in hydrochlorid acid pickles (20 g/l HCl) at ambient temperature as well as in cleaners containing hydrochloric acid (10-30 g/l HCl) at 40 C when other conditions also applied. Above all, local corrosion was produced if the inhibitor concentration became too low (0.2 g/l) in connection with a minimum hydrochloric acid concentration (10-30 g/l). However, oxidizing agents like iron(III)-ions (5-10 g/l), atmospheric oxygen and free chlorine (100-1000 mg/l) lead to local corrosion, too. Local corrosion did not emerge in rinse baths (2-10 g/l HCl) and fluxing material solutions of zinc chloride and ammonium chloride (pH value: 2.0-5.5). Here uniform corrosion developed. Acid inhibitors turned out to be very effective against uniform corrosion in the examined long-time period (inhibiting values up to 99%). (Abstract Copyright [2004], Wiley Periodicals, Inc.) [German] Die Wirksamkeit handelsueblicher Saeureinhibitoren wird durch eine Auslagerung von Grobblechen aus Behaelterstahl ueber 1000 Stunden in technisch gebraeuchlichen Loesungen der Feuerverzinkung untersucht. Oertliche Korrosion ist als Muldenkorrosion in Gegenwart von Saeureinhibitoren vor allem in Salzsaeurebeizen (20 g/l HCl) bei Raumtemperatur und in salzsaeurehaltigen Reinigern (10-30 g/l HCl) bei 40 C aufgetreten, wenn Zusatzbedingungen erfuellt sind. Oertliche Korrosion wird vorwiegend durch eine Unterschreitung der Inhibitorkonzentration (0,2 g/l) in Verbindung mit einer minimalen Salzsaeurekonzentration (10-30 g/l) ausgeloest. Aber auch Oxidationsmittel wie Eisen(III)-Ionen (5-10 g/l), Luftsauerstoff und freies Chlor (100-1000 mg/l) fuehren zu oertlicher Korrosion. In Spuelbaedern (2-10 g/l HCl) und Flussmittelloesungen aus Zinkchlorid und Ammoniumchlorid (p

  7. Separation and determination of some carboxylic acids by capillary electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Sladkov, V.; Fourest, B

    2006-07-01

    Separation and determination of some organic acids, mono-carboxylic (formic and acetic), dicarboxylic (oxalic and tartaric), tricarboxylic (citric) acids and aromatic acids (phtalic, benzoic, mellitic and trimellitic), by capillary electrophoresis are reviewed. The method development parameters, such as separation and injection mode, are discussed. Special attention is paid to the comparison of different detection types (spectroscopic and electrochemical). The optimisation of the carrier electrolyte composition (choice of carrier electrolyte, effect of pH, ionic strength, electro-osmotic flow modifier) is treated. Different additives (alkali-earth and transition metal ions, cyclodextrins and alcohol), which are often used for improving organic acid separation, are also considered. (authors)

  8. Separation and determination of some carboxylic acids by capillary electrophoresis

    International Nuclear Information System (INIS)

    Sladkov, V.; Fourest, B.

    2006-01-01

    Separation and determination of some organic acids, mono-carboxylic (formic and acetic), dicarboxylic (oxalic and tartaric), tricarboxylic (citric) acids and aromatic acids (phtalic, benzoic, mellitic and trimellitic), by capillary electrophoresis are reviewed. The method development parameters, such as separation and injection mode, are discussed. Special attention is paid to the comparison of different detection types (spectroscopic and electrochemical). The optimisation of the carrier electrolyte composition (choice of carrier electrolyte, effect of pH, ionic strength, electro-osmotic flow modifier) is treated. Different additives (alkali-earth and transition metal ions, cyclodextrins and alcohol), which are often used for improving organic acid separation, are also considered. (authors)

  9. Cs separation from nitric acid solutions of radioactive waste

    International Nuclear Information System (INIS)

    Heckmann, K.; Pieronczyk, W.; Strnad, J.; Feldmaier, F.

    1989-01-01

    It was the objective of this study to selectively separate active caesium (Cs-134 and Cs-137) from acid radioactive waste solutions (especially MAW and HAWC). The following 'strategy' was designed for a separation process: synthesis of reagents which are acid-resistant and selective for caesium; precipitation of Cs + and separation of the precipitates by filtration or centrifugation or precipitation of Cs + and separation of the precipitates by flotation; caesium separation by liquid-liquid extraction. As precipitating agents, sodium tetraphenylborate (kalignost) and several of its fluorine derivatives were examined. (orig./RB) [de

  10. Separation of caesium-137 from fission products using phosphotungstic acid

    International Nuclear Information System (INIS)

    Murthy, T.S.; Balasubramaniam, K.R.; Ananthakrishnan, M.; Varma, R.N.

    1977-01-01

    Separation of caesium 137 from fission products using phosphotungstic acid is reported. Phosphotungstate caesium is precipitated as caesium from fission product waste solution in acid medium and subsequently purified. Separation of phosphate and tungstate ions has been done using a typical hydrous oxide like alumina. The exchange capacity of alumina for phosphate and tungstate ions, and the purity of the product are determined. Results are discussed. Based on the findings a procedure is recommended for caesium 137 separation. (A.K.)

  11. Isotachophoresis. The separation of amino acids

    NARCIS (Netherlands)

    Everaerts, F.M.; Put, van der A.J.M.

    1970-01-01

    There are several instrumental methods of analysis available for amino acids. The most important ones are ion-exchange chromatography (Stein and Moore), gas chromatography and paper chromatography. These techniques all have various disadvantages; the time for analysis may be long or the sample

  12. 'Americium(III)/trivalent lanthanides' separation using organothiophosphinic acids

    International Nuclear Information System (INIS)

    Hill, C.; Madic, C.; Baron, P.; Ozawa, Masaki; Tanaka, Yasumasa.

    1997-01-01

    The present paper describes the extraction of neodymium and other lanthanides by saponified Cyanex 301 acid. The saponification of commercial Cyanex 301 acid favoured the extraction of macro concentrations of neodymium from sodium nitrate aqueous solutions (pH eq ∼ 4). The amount of lanthanide extracted in the organic phase always reached the third of the initial concentration of saponified Cyanex 301 acid, which assumed a cation exchange mechanism to occur during the extraction. No nitrate anion took part in the complex formation. This paper also compares the abilities of purified Cyanex 301, Cyanex 302 and Cyanex 272 acids to extract and separate 241 Am(III) from 152 Eu(III). Very high separation factors S.F. Am/Eu were observed in the case of purified Cyanex 301 acid. Finally some studies are presented herein using tri-n-butylphosphate (TBP) as a synergistic extractant with Cyanex 301 acid to separate actinides from trivalent lanthanide. (author)

  13. Separation of ions in acidic solution by capillary electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Thornton, Michelle [Iowa State Univ., Ames, IA (United States)

    1997-10-08

    Capillary electrophoresis (CE) is an effective method for separating ionic species according to differences in their electrophoretic mobilities. CE separations of amino acids by direct detection are difficult due to their similar electrophoretic mobilities and low absorbances. However, native amino acids can be separated by CE as cations at a low pH by adding an alkanesulfonic acid to the electrolyte carrier which imparts selectivity to the system. Derivatization is unnecessary when direct UV detection is used at 185 nm. Simultaneous speciation of metal cations such as vanadium (IV) and vanadium (V) can easily be performed without complexation prior to analysis. An indirect UV detection scheme for acidic conditions was also developed using guanidine as the background carrier electrolyte (BCE) for the indirect detection of metal cations. Three chapters have been removed for separate processing. This report contains introductory material, references, and general conclusions. 80 refs.

  14. Amine-oxide hybrid materials for acid gas separations

    KAUST Repository

    Bollini, Praveen; Didas, Stephanie A.; Jones, Christopher W.

    2011-01-01

    Organic-inorganic hybrid materials based on porous silica materials functionalized with amine-containing organic species are emerging as an important class of materials for the adsorptive separation of acid gases from dilute gas streams

  15. Spectroscopic studies and thermal analysis of mononuclear metal complexes with moxifloxacin and 2,2‧-bipyridine and their effects on acute lung injury induced by hydrochloric acid in rats

    Science.gov (United States)

    El-Hamid, S. M. Abd; El-Demerdash, R. S.; Arafat, H. F. H.; Sadeek, S. A.

    2017-12-01

    The article describes the interaction of Y(III), Zr(IV), La(III), Ce(IV) and U(VI) with moxifloxacin hydrochloride and 2,2‧-bipyridine. Characterization of complexes was made by elemental analyses, molar conductivity, magnetic moment measurements and spectral measurements e.g. IR, UV-Vis., 1H NMR and mass as well as thermal analyses (TG and DTG). The molar conductivity shows that the complexes are electrolytes nature. Spectroscopic investigation of the solid complexes studied here indicate that moxifloxacin hydrochloride and 2,2‧-bipyridine are coordinated to the metal ions in a neutral bidentate manner. After complete characterization, the chemical formulae of the complexes were established. The calculated bond length and force constant, F(Udbnd O), in the uranyl complex are 1.756 Å and 637.90 Nm-1, respectively. Kinetic and thermodynamic parameters were determined using Coats-Redfern and Horowitz-Metzger equations. Establishment of hydrochloric acid that induce acute lung injury (ALI) in rats by intratracheal administration through damaging the alveolar epithelium and activation of the neutrophil and subsequent oxidative stress by increasing malondialdehyde (MDA), tumor necrosis factor (TNF-α) and neutrophil, which were confirmed by histopathological investigation while decreasing in antioxidant enzymes and lymphocytes. Whereas treatment with mixed-ligand metal complexes significantly decrease MDA, TNF-α and neutrophils and increase antioxidant and lymphocytes.

  16. Chromatographic separation of europium and gadolinum mixtures by ethylenediaminedisuccinic acid

    International Nuclear Information System (INIS)

    Kolleganov, M.Yu.; Nazarov, P.P.; Martynenko, L.I.; Mtrofanova, N.D.; Spitsyn, V.I.

    1985-01-01

    Comparative investigation of chromatographic separation of impurities of Eu and Gd micro- and macroquantities by means of ethylenediaminedisuccinic (EDDS) and ethylene-diaminetetraacetic (EDTA) acids is performed. It is shown that EDTA is a sufficiently effective agent for separation of this pair of elements. The values of EU and Gd separation coefficients obtained in experiments with RE microquantities are not realized at Eu-Gd, macroquantities separation which probably is connected with the influence of polymerization processes in the systems containing RE and EDDS complexes

  17. Interference effects from coexisting fatty acids on elaidic acid separation by fractionating crystallization: A model study

    DEFF Research Database (Denmark)

    Jala, Ram Chandra Reddy; Guo, Zheng; Bjerring, Thomas

    2010-01-01

    A multi-stage temperature-programmed fractionating crystallization process was carried out to examine the effects of the presence of stearic acid (SA), oleic acid (OA), and linoleic acid (LA) on the separation of elaidic acid (EA). The results showed that the efficiency of fractionating...

  18. Lanthanides separation by counter - current electrophoretic using α - hydroxyisobutyric acid

    International Nuclear Information System (INIS)

    Alleluia, I.B.

    1975-01-01

    Studies about counter-current electrophoretic separation of rare earth metal ions using α-hydroxyisobutyric acid as complexing electrolyte are discussed. La, Pr, Nd, Sm and Eu were separated and fractions with purities better than 99,9% were obtained, using neutron activation analysis. A relation between the first stability constant of the α-hydroxyisobutyrate/lanthanide complexes and their migration velocities were observed. (M.J.C.) [pt

  19. The water soluble composite poly(vinylpyrrolidone–methylaniline: A new class of corrosion inhibitors of mild steel in hydrochloric acid media

    Directory of Open Access Journals (Sweden)

    R. Karthikaiselvi

    2017-02-01

    Full Text Available In recent years poly methyl aniline has been reported as one of the efficient corrosion inhibitors of mild steel in acidic media. In view of the major limitation of the insolubility of polymethyl aniline PMA, we propose to convert PMA into a water soluble composite using supporting polymer polyvinylpyrrolidone to get higher solubility and corrosion inhibition efficiency. The water soluble composite poly(vinylpyrrolidone-methyl aniline was synthesized by chemical oxidative polymerization and its inhibitive effect on mild steel in 1 M HCl has been investigated using weight loss and electrochemical techniques (potentiodynamic polarization studies and impedance spectroscopy. SEM and EDX analyses are carried out to establish a protective film formation on the metal surface.

  20. Correlating electronic structure with corrosion inhibition potentiality of some bis-benzimidazole derivatives for mild steel in hydrochloric acid: Combined experimental and theoretical studies

    International Nuclear Information System (INIS)

    Dutta, Alokdut; Saha, Sourav Kr.; Banerjee, Priyabrata; Sukul, Dipankar

    2015-01-01

    Highlights: • Bis-benzimidazole derivatives as good corrosion inhibitors for mild steel in acid. • Simultaneous both way electron-transfer is expected to occur during adsorption. • Role of molecular conformation on inhibition efficiency is demonstrated. • Good correlation between inhibition efficiency and molecular parameters established. • MD simulation results support experimental observations. - Abstract: Four different bis-benzimidazole (BBI) derivatives, tested as potential corrosion inhibitors for mild steel in 1 M HCl, have revealed good inhibition efficiency for long period of exposure. Inhibitors impart high resistance towards charge transfer across metal–electrolyte interface and behave broadly as mixed type. DFT calculations are used to correlate inhibition potentiality with intrinsic molecular parameters. From the optimized geometry of BBI derivatives, electron distribution in HOMO and LUMO and Fukui indices of each atom, possible modes of interaction of BBI derivatives with mild steel surface have been predicted. Energy corresponding to inhibitor-metal surface interaction is evaluated following molecular dynamics simulation

  1. Inhibition Effects of a Synthesized Novel 4-Aminoantipyrine Derivative on the Corrosion of Mild Steel in Hydrochloric Acid Solution together with Quantum Chemical Studies

    Directory of Open Access Journals (Sweden)

    Abu Bakar Mohamad

    2013-06-01

    Full Text Available 1,5-Dimethyl-4-((2-methylbenzylideneamino-2-phenyl-1H-pyrazol-3(2H-one (DMPO was synthesized to be evaluated as a corrosion inhibitor. The corrosion inhibitory effects of DMPO on mild steel in 1.0 M HCl were investigated using electrochemical impedance spectroscopy (EIS, potentiodynamic polarization, open circuit potential (OCP and electrochemical frequency modulation (EFM. The results showed that DMPO inhibited mild steel corrosion in acid solution and indicated that the inhibition efficiency increased with increasing inhibitor concentration. Changes in the impedance parameters suggested an adsorption of DMPO onto the mild steel surface, leading to the formation of protective films. The novel synthesized corrosion inhibitor was characterized using UV-Vis, FT-IR and NMR spectral analyses. Electronic properties such as highest occupied molecular orbital energy, lowest unoccupied molecular orbital energy (EHOMO and ELUMO, respectively and dipole moment (μ were calculated and discussed. The results showed that the corrosion inhibition efficiency increased with an increase in the EHOMO values but with a decrease in the ELUMO value.

  2. Inhibition Effects of a Synthesized Novel 4-Aminoantipyrine Derivative on the Corrosion of Mild Steel in Hydrochloric Acid Solution together with Quantum Chemical Studies

    Science.gov (United States)

    Junaedi, Sutiana; Al-Amiery, Ahmed A.; Kadihum, Abdulhadi; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar

    2013-01-01

    1,5-Dimethyl-4-((2-methylbenzylidene)amino)-2-phenyl-1H-pyrazol-3(2H)-one (DMPO) was synthesized to be evaluated as a corrosion inhibitor. The corrosion inhibitory effects of DMPO on mild steel in 1.0 M HCl were investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, open circuit potential (OCP) and electrochemical frequency modulation (EFM). The results showed that DMPO inhibited mild steel corrosion in acid solution and indicated that the inhibition efficiency increased with increasing inhibitor concentration. Changes in the impedance parameters suggested an adsorption of DMPO onto the mild steel surface, leading to the formation of protective films. The novel synthesized corrosion inhibitor was characterized using UV-Vis, FT-IR and NMR spectral analyses. Electronic properties such as highest occupied molecular orbital energy, lowest unoccupied molecular orbital energy (EHOMO and ELUMO, respectively) and dipole moment (μ) were calculated and discussed. The results showed that the corrosion inhibition efficiency increased with an increase in the EHOMO values but with a decrease in the ELUMO value. PMID:23736696

  3. DFT theoretical study of 7-R-3methylquinoxalin-2(1H)-thiones (R=H; CH3; Cl) as corrosion inhibitors in hydrochloric acid

    International Nuclear Information System (INIS)

    El Adnani, Z.; Mcharfi, M.

    2013-01-01

    Highlights: ► A theoretical study of three quinoxaline derivatives. ► We try to explain their experimental mild steel corrosion inhibition efficiencies. ► The solvent effect was also depicted using the PCM model. ► Most of the global reactivity descriptors agree well with the experimental results. ► The results show that the sulphur atom is probably the main adsorption site. - Abstract: Quantum chemical approach at B3LYP/6-31G(d,p) level of theory, was used to calculate some structural and electronic properties of three quinoxaline derivatives, recently reported as mild steel corrosion inhibitors in acidic media, to ascertain the correlation between their experimental inhibitive efficiencies and some of the computed parameters. The results of most of the global reactivity descriptors show that the experimental and theoretical studies agree well and confirm that Me-Q=S is a better inhibitor than Q=S and Cl-Q=S, respectively. In addition, the local reactivity, analyzed through Fukui functions, show that the sulphur atom will be the main adsorption site.

  4. Survival of Escherichia coli O157:H7 in synthetic gastric fluid after cold and acid habituation in apple juice or trypticase soy broth acidified with hydrochloric acid or organic acids.

    Science.gov (United States)

    Uljas, H E; Ingham, S C

    1998-08-01

    Extreme acid tolerance of Escherichia coli O157:H7 has raised doubts about the safety of acidic foods. This study examined whether prior storage in acidic and/or cold conditions enhanced survival of E. coli O157:H7 in synthetic gastric fluid (SGF). Three E. coli O157:H7 strains were stored in trypticase soy broth (TSB; acidified with HCl, malic acid, citric acid, or lactic acid) or pH 3.5 and 6.5 (nonacidic control) apple juice at 4 and 21 degrees C for acids, suggesting that juice constituents other than organic acids protect E. coli O157:H7. Refrigeration combined with low pH best protected cells in apple juice and acidified TSB, but, compared to the nonacidic control, only acidified TSB enhanced subsequent survival in pH 2.5 SGF. Equal survival in SGF occurred after storage in pH 3.5 or 6.5 apple juice at 4 degrees C, suggesting that low temperature alone in apple juice enhanced acid tolerance. Two strains stored at 4 degrees C in TSB containing malic or citric acid subsequently survived better in SGF than cells stored in nonacidified TSB but poorer than cells stored in the presence of HCl. These differences reflect the higher pKa of these organic acids. However, subsequent survival of these strains in SGF was poorer after refrigerated storage in apple juice than in TSB containing citric or malic acids. Cells stored in lactic acid were most likely to be completely eliminated upon transfer to SGF. Differences in survival in storage media or SGF related to strain, storage conditions, or acidifier were consistent and often statistically significant (P acidic beverages may not be affected by the type of acidifier used, the subsequent survival in SGF of this pathogen may be critically dependent on this factor.

  5. Non toxic biodegradable cationic gemini surfactants as novel corrosion inhibitor for mild steel in hydrochloric acid medium and synergistic effect of sodium salicylate: Experimental and theoretical approach

    Energy Technology Data Exchange (ETDEWEB)

    Mobin, Mohammad, E-mail: drmmobin@hotmail.com; Aslam, Ruby; Aslam, Jeenat

    2017-04-15

    Two biodegradable, non toxic cationic gemini surfactants having ester linkage in the spacer namely, C{sub m}H{sub 2m+1}(CH{sub 3}){sub 2}N{sup +}(CH{sub 2}COOCH{sub 2}){sub 2}N{sup +}(CH{sub 3}){sub 2}C{sub m}H{sub 2m+1}.2Cl{sup -} (m-E2-m, m = 12, 14), were synthesized and characterized using elemental analysis, FT-IR and {sup 1}H-NMR. The corrosion inhibition performance of synthesized compounds separately and in combination with sodium salicylate (SS), along with the nature and stability of inhibitive film, for mild steel (MS) in 1 M HCl solution at 30–60 °C was evaluated using weight loss, potentiodynamic polarization, EIS, UV–visible spectroscopy, FTIR, SEM/EDAX, TGA and quantum chemical calculations. Results of the studies confirm m-E2-m as effective corrosion inhibitor for MS in HCl; the inhibition effect being synergistically strengthened in presence of SS. The synthesized compounds act as mixed type inhibitor and adsorb on MS surface in accordance with Langmuir adsorption isotherm. Experimentally measured inhibition efficiencies are correlated with the molecular parameters obtained using PM6 semi-empirical method. Empirical results are in good agreement with the theoretical predictions. - Graphical abstract: (a) Optimized geometry of studied inhibitors by PM6 method with (b) HOMO and (c) LUMO orbital occupation. - Highlights: • Environment friendly gemini surfactants were studied as corrosion inhibitor for MS. • Studied compounds act as good inhibitor for MS corrosion in 1 M HCl at 30–60 °C. • η of inhibitors is synergistically increased in presence of sodium salicylate. • The synthesized cationic gemini surfactants act as mixed-type inhibitor. • Experimentally obtained results are in good agreement with theoretical results.

  6. ac impedance, X-ray photoelectron spectroscopy and density functional theory studies of 3,5-bis(n-pyridyl)-1,2,4-oxadiazoles as efficient corrosion inhibitors for carbon steel surface in hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Outirite, Moha; Lagrenee, Michel; Lebrini, Mounim [Unite de Catalyse et de Chimie du Solide, UMR-CNRS 8181, ENSCL, B.P. 90108, F-59652 Villeneuve d' Ascq Cedex (France); Traisnel, Michel; Jama, Charafeddine [Laboratoire des Procedes d' Elaboration des Revetements Fonctionnels, PERF UMR-CNRS 8008, ENSCL, B.P. 90108, F-59652 Villeneuve d' Ascq Cedex (France); Vezin, Herve [Laboratoire de Chimie Organique et Macromoleculaire, UMR-CNRS 8009, USTL Bat C4, F-59655 Villeneuve d' Ascq Cedex (France); Bentiss, Fouad, E-mail: fbentiss@enscl.f [Laboratoire de Chimie de Coordination et d' Analytique, Faculte des Sciences, Universite Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco)

    2010-02-01

    The corrosion inhibition properties of a new class of oxadiazole derivatives, namely 3,5-bis(n-pyridyl)-1,2,4-oxadiazoles (n-DPOX) for C38 carbon steel corrosion in 1 M HCl medium were analysed by electrochemical impedance spectroscopy (EIS). An adequate structural model of the interface was used and the values of the corresponding parameters were calculated and discussed. The experimental results showed that these compounds are excellent inhibitors for the C38 steel corrosion in acid solution and that the protection efficiency increased with increasing the inhibitors concentration. Electrochemical impedance data demonstrate that the addition of the n-DPOX derivatives in the corrosive solution decreases the charge capacitance and simultaneously increases the function of the charge/discharge of the interface, facilitating the formation of an adsorbed layer over the steel surface. Adsorption of these inhibitors on the steel surface obeys to the Langmuir adsorption isotherm. X-ray photoelectron spectroscopy (XPS) and the thermodynamic data of adsorption showed that inhibition of steel corrosion in normal hydrochloric solution by n-DPOX is due to the formation of a chemisorbed film on the steel surface. Quantum chemical calculations using the Density Functional Theory (DFT) and the Quantitative Structure Activity Relationship (QSAR) approach were performed on n-DPOX derivatives to determine the relationship between molecular structure and their inhibition efficiencies. The results of the quantum chemical calculations and experimental inhibition efficiency were subjected to correlation analysis and indicate that their inhibition effect is closely related to E{sub HOMO}, E{sub LUMO}, and dipole moment (mu).

  7. Separation of thulium, ytterbium and lutetium from uranium

    International Nuclear Information System (INIS)

    Lopez, G.H.

    1987-01-01

    The behaviour at different temperatures, shaking times and hydrochloric acid concentrations on the solvent extraction system UO 2 2+ - (Tm 3+ , Yb 3+ , Lu 3+ ) - H 2 O - HCl - TBP was studied. Quantitative determinations of the elements were performed by visible spectrophotometry and X-ray fluorescence. The uranyl ion was efficiently extracted by TBP from an aqueous hydrochloric acid solution (4-7M) shaken during 10 minutes at room temperature. On these conditions the separation factors for uranium from thulium and ytterbium were found to be 3000 and from lutetium 140. (author)

  8. Leachability of nitrided ilmenite in hydrochloric acid

    CSIR Research Space (South Africa)

    Swanepoel, JJ

    2010-10-01

    Full Text Available Titanium nitride in upgraded nitrided ilmenite (bulk of iron removed) can selectively be chlorinated to produce titanium tetrachloride. Except for iron, most other components present during this low temperature (ca. 200 °C) chlorination reaction...

  9. Improvement in HPLC separation of acetic acid and levulinic acid in the profiling of biomass hydrolysate.

    Science.gov (United States)

    Xie, Rui; Tu, Maobing; Wu, Yonnie; Adhikari, Sushil

    2011-04-01

    5-Hydroxymethylfurfural (HMF) and furfural could be separated by the Aminex HPX-87H column chromatography, however, the separation and quantification of acetic acid and levulinic acid in biomass hydrolysate have been difficult with this method. In present study, the HPLC separation of acetic acid and levulinic acid on Aminex HPX-87H column has been investigated by varying column temperature, flow rate, and sulfuric acid content in the mobile phase. The column temperature was found critical in resolving acetic acid and levulinic acid. The resolution for two acids increased dramatically from 0.42 to 1.86 when the column temperature was lowered from 60 to 30 °C. So did the capacity factors for levulinic acid that was increased from 1.20 to 1.44 as the column temperature dropped. The optimum column temperature for the separation was found at 45 °C. Variation in flow rate and sulfuric acid concentration improved not as much as the column temperature did. Published by Elsevier Ltd.

  10. Separation of Transfer Ribonucleic Acids by Reverse Phase Chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Kelmers, A. D.; Novelli, G. David; Stulberg, M. P.

    1965-10-01

    Numerous experimental techniques for the separation of transfer ribonucleic acids have been successful in preparing partially purified fractions of several specific t-RNAs. Many of the existing methods have depended upon the differential solubility of specific t-RNAs in complex two-phase systems (1-6) and the separation was achieved by means of counter-current extraction techniques. Column chromatography experiments using cellulose exchangers, (7,8) methylated albumin (9,10) or with solvent phases supported on inert material (11-13) have also shown partial separation of specific t-RNAs. Paper chromatographic procedures have produced partial resolutions of t-RNA.14 Methods involving chemical treatment of specific t-RNAs have been reported (15-19).

  11. Separation and preconcentration of actinides from acidic media by extraction chromatography

    International Nuclear Information System (INIS)

    Horwitz, E. Philip; Chiarizia, Renato; Dietz, Mark L.; Diamond, Herbert; Nelson, Donald M.

    1993-01-01

    A systematic examination of the effect of nitric and hydrochloric acid concentrations and of macro levels of selected elements on the sorption of actinide ions by a novel extraction chromatographic resin comprised of a solution of octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide in tri-n-butyl phosphate supported on an inert polymeric substrate is described. Actinide sorption is demonstrated to be most efficient at high (>1 M) nitric acid concentrations, although tetra- and hexavalent actinides are strongly retained even from dilute (e.g., 0.05 M) nitric acid solutions. Macro concentrations of several common anions (e.g., PO 4 3- and SO 4 2- ) or complexing agents (e.g., oxalic acid) are shown not to adversely affect the sorption of trivalent actinides, while reducing the sorption of tetravalents. Such effects, together with oxidation state adjustments, are shown to provide a basis for the sequential elution of individual actinides and for actinide isolation from environmental and biological matrices

  12. Acetic acid denaturing pulsed field capillary electrophoresis for RNA separation.

    Science.gov (United States)

    Li, Zhenqing; Dou, Xiaoming; Ni, Yi; Sumitomo, Keiko; Yamaguchi, Yoshinori

    2010-10-01

    Based on our previous work of in-capillary denaturing polymer electrophoresis, we present a study of RNA molecular separation up to 6.0 kilo nucleotide by pulsed field CE. This is the first systematic investigation of electrophoresis of a larger molecular mass RNA in linear hydroxyethylcellulose (HEC) under pulsed field conditions. The parameters that may influence the separation performance, e.g. gel polymer concentration, modulation depth and pulse frequency, are analyzed in terms of resolution and mobility. For denaturing and separating RNA in the capillary simultaneously, 2 M acetic acid was added into the HEC polymer to serve as separation buffer. Result shows that (i) in pulsed field conditions, RNA separation can be achieved in a wide range of concentration of HEC polymer, and RNA fragments between 0.3 and 0.6 kilo nucleotide are sensitive to the polymer concentration; (ii) under certain pulsed field conditions, RNA fragments move linearly as the modulation depth increases; (iii) 12.5 Hz is the resonance frequency for RNA reorientation time and applied frequency.

  13. Separation of viable lactic acid bacteria from fermented milk

    Directory of Open Access Journals (Sweden)

    Tomohiko Nishino

    2018-04-01

    Full Text Available Probiotics are live microorganisms that provide health benefits to humans. Some lactic acid bacteria (LAB are probiotic organisms used in the production of fermented foods, such as yogurt, cheese, and pickles. Given their widespread consumption, it is important to understand the physiological state of LAB in foods such as yogurt. However, this analysis is complicated, as it is difficult to separate the LAB from milk components such as solid curds, which prevent cell separation by dilution or centrifugation. In this study, we successfully separated viable LAB from yogurt by density gradient centrifugation. The recovery rate was >90 %, and separation was performed until the stationary phase. Recovered cells were observable by microscopy, meaning that morphological changes and cell viability could be directly detected at the single-cell level. The results indicate that viable LAB can be easily purified from fermented milk. We expect that this method will be a useful tool for the analysis of various aspects of probiotic cells, including their enzyme activity and protein expression. Keywords: Food analysis, Microbiology

  14. Separation of uranium(VI) by liquid-solid extraction with tri-n-octylphosphine oxide diluted with naphthalene

    International Nuclear Information System (INIS)

    Shigetomi, Y.; Kojima, T.; Kamba, H.; Yamamoto, Y.

    1980-01-01

    Liquid-liquid distribution with tri-n-octylphosphine oxide (TOPO) and molten naphthalene has been investigated for the extraction of 20 metals from nitric acid and hydrochloric acid solutions. Uranium is quantitatively extracted from 1 M nitric acid or hydrochloric acid by using 100 mg of TOPO and 200 mg of naphthalene and shaking for 5 min at 80 0 C, and separated from transition metals, alkaline earth metals and rare earth metals (except scandium). Addition of naphthalene increases the extraction efficiency. (Auth.)

  15. Separation of uranium from molybdenum by alkyl phosphoric acid extraction

    Energy Technology Data Exchange (ETDEWEB)

    Zhongshi, Li

    1986-08-01

    The regularities of separation of uranium from molybdenum by alkyl phosphoric acid extraction are described. Two parameters, i.e., density ratio of uranium to molybdenum in organic phase at first stage and density of uranium in raffinate at last stage are presented. The relationship between these parameters and purity of molybdenum and uranium products is given. The method of adjusting and controlling these parameters in experiments and production is worked out. The technical key problem in comprehensive utilization of sedimentary type uranium ore containing molybdenum with close concentration of these to elements has been solved.

  16. Diphosphonic acid complexants for improved separation efficiency of transuranic elements

    International Nuclear Information System (INIS)

    Nash, K.L.

    1994-01-01

    A study was made of the thermodynamics of protonation and complexation of Eu(III), Th(IV), and U(VI) by a series of simple diphosphonic acid chelating agents to assess the potential for application in actinide waste processing. It was found that the strongest complexes are formed with ligands having two phosphonate binding groups on the same C atom (1,1-diphosphonates) and that the water-soluble complexes are formed with protonated ligand species. More efficient separation/recovery processes could be designed using these ligands

  17. Distillation Separation of Hydrofluoric Acid and Nitric Acid from Acid Waste Using the Salt Effect on Vapor-Liquid Equilibrium

    Science.gov (United States)

    Yamamoto, Hideki; Sumoge, Iwao

    2011-03-01

    This study presents the distillation separation of hydrofluoric acid with use of the salt effect on the vapor-liquid equilibrium for acid aqueous solutions and acid mixtures. The vapor-liquid equilibrium of hydrofluoric acid + salt systems (fluorite, potassium nitrate, cesium nitrate) was measured using an apparatus made of perfluoro alkylvinylether. Cesium nitrate showed a salting-out effect on the vapor-liquid equilibrium of the hydrofluoric acid-water system. Fluorite and potassium nitrate showed a salting-in effect on the hydrofluoric acid-water system. Separation of hydrofluoric acid from an acid mixture containing nitric acid and hydrofluoric acid was tested by the simple distillation treatment using the salt effect of cesium nitrate (45 mass%). An acid mixture of nitric acid (5.0 mol · dm-3) and hydrofluoric acid (5.0 mol · dm-3) was prepared as a sample solution for distillation tests. The concentration of nitric acid in the first distillate decreased from 5.0 mol · dm-3 to 1.13 mol · dm-3, and the concentration of hydrofluoric acid increased to 5.41 mol · dm-3. This first distillate was further distilled without the addition of salt. The concentrations of hydrofluoric acid and nitric acid in the second distillate were 7.21 mol · dm-3 and 0.46 mol · dm-3, respectively. It was thus found that the salt effect on vapor-liquid equilibrium of acid mixtures was effective for the recycling of acids from acid mixture wastes.

  18. Novel reprocessing methods with nuclide separation for volume reduction of high level radioactive waste

    International Nuclear Information System (INIS)

    Suzuki, Tatsuya

    2015-01-01

    We have proposed the reprocessing system with nuclide separation processes based on the chromatographic technique in the hydrochloric acid solution system. Our proposing system consists of the dissolution process, the reprocessing process, the MA separation process, and nuclide separation processes. In our proposing processes, the pyridine resin is used as a main separation media. We expect that our proposing will contribute to that volume reduction of high level radioactive waste by combining the transmutation techniques, usage of valuable elements, and so on. (author)

  19. Thermal decomposition of hydroiodic acid and hydrogen separation

    International Nuclear Information System (INIS)

    Yeheskel, J.; Leger, D.; Courvoisier, P.

    1978-01-01

    The reaction of decomposition of hydroiodic acid is included in a promising water splitting process (sulfur-iodine cycle). An experimental program is running in order to overcome some basic difficulties and data shortcomings which stand in the way of achieving that target. The core of the experimental system is the palladium silver (23% Ag) membrane tube reactor in which the feed gas entered the inner side of the tube. Four series of different kinds of experiments have been performed: 1) diffusion of hydrogen from a pure feed hydrogen stream through the membrane; the results are statistically analyzed due to the present correlations of the H 2 specific permeability as a function of temperature and pressure (up to 600 0 C and 20 bar); 2) separation of hydrogen from a binary feed mixture H 2 -He; a mathematical model is developed for this operation; 3) indication of the poisoning effect of a little amount of hydroiodic acid on the hydrogen pereability; this effect is partly reversible at high temperatures; 4) a performance of one continuous experiment of HI decomposition into the membrane tube at steady pressure and temperature of 8 bar and 500 0 C; the results prove the catalytic activity of the membrane surface

  20. Bifidobacterium breve with α-linolenic acid and linoleic acid alters fatty acid metabolism in the maternal separation model of irritable bowel syndrome.

    Science.gov (United States)

    Barrett, Eoin; Fitzgerald, Patrick; Dinan, Timothy G; Cryan, John F; Ross, R Paul; Quigley, Eamonn M; Shanahan, Fergus; Kiely, Barry; Fitzgerald, Gerald F; O'Toole, Paul W; Stanton, Catherine

    2012-01-01

    The aim of this study was to compare the impact of dietary supplementation with a Bifidobacterium breve strain together with linoleic acid & α-linolenic acid, for 7 weeks, on colonic sensitivity and fatty acid metabolism in rats. Maternally separated and non-maternally separated Sprague Dawley rats (n = 15) were orally gavaged with either B. breve DPC6330 (10(9) microorganisms/day) alone or in combination with 0.5% (w/w) linoleic acid & 0.5% (w/w) α-linolenic acid, daily for 7 weeks and compared with trehalose and bovine serum albumin. Tissue fatty acid composition was assessed by gas-liquid chromatography and visceral hypersensitivity was assessed by colorectal distension. Significant differences in the fatty acid profiles of the non-separated controls and maternally separated controls were observed for α-linolenic acid and arachidonic acid in the liver, oleic acid and eicosenoic acid (c11) in adipose tissue, and for palmitoleic acid and docosahexaenoic acid in serum (pbreve DPC6330 to MS rats significantly increased palmitoleic acid, arachidonic acid and docosahexaenoic acid in the liver, eicosenoic acid (c11) in adipose tissue and palmitoleic acid in the prefrontal cortex (pbreve DPC6330 to non separated rats significantly increased eicosapentaenoic acid and docosapentaenoic acid in serum (pbreve DPC6330 in combination with linoleic acid and α-linolenic acid to maternally separated rats significantly increased docosapentaenoic acid in the serum (pbreve DPC6330 with fatty acid supplementation to non-separated rats significantly increased liver and serum docosapentaenoic acid (pbreve DPC6330 influenced host fatty acid metabolism. Administration of B. breve DPC6330 to maternally separated rats significantly modified the palmitoleic acid, arachidonic acid and docosahexaenoic acid contents in tissues. The effect was not observed in non-separated animals.

  1. Amine-oxide hybrid materials for acid gas separations

    KAUST Repository

    Bollini, Praveen

    2011-01-01

    Organic-inorganic hybrid materials based on porous silica materials functionalized with amine-containing organic species are emerging as an important class of materials for the adsorptive separation of acid gases from dilute gas streams. In particular, these materials are being extensively studied for the adsorption of CO 2 from simulated flue gas streams, with an eye towards utilizing these materials as part of a post-combustion carbon capture process at large flue gas producing installations, such as coal-fired electricity-generating power plants. In this Application Article, the utilization of amine-modified organic-inorganic hybrid materials is discussed, focusing on important attributes of the materials, such as (i) CO 2 adsorption capacities, (ii) adsorption and desorption kinetics, and (iii) material stability, that will determine if these materials may one day be useful adsorbents in practical CO 2 capture applications. Specific research needs and limitations associated with the current body of work are identified. © 2011 The Royal Society of Chemistry.

  2. Contributions to anionexchange separation of metal ions in mixed aqueous-organic solvent systems

    International Nuclear Information System (INIS)

    Cunha-Campos, C.

    1986-01-01

    In the first chapter of the thesis a method is described for the determination of iron, copper, manganese, nickel, cobalt and uranium in samples of manganese nodules. After dissolution of the sample in a mixture of concentrated hydrochloric-nitric acids, the elements are adsorbed on a column of the strongly basic anion-exchange resin Dowex 1 from a medium consisting of 80% cyclohexanone 10% methanol and 10% 1M hydrochloric acid. Following removal of iron by washing the resin bed with a mixture of the same composition, 90% methanol-10% 1M hydrochloric containing ascorbic acid is passed through the column to eluate manganese, nickel and cobalt. Subsequently, 4M hydrochloric acid-1% hydrogen peroxid solution and 1M hydrochloric acid are used to elute copper and uranium, respectively. The elements were determined quantitatively by ICP-OES, except for uranium which was determined by fluorimetry. The method was used successfully for the determination of mg and p.p.m. quantities of these elements in samples of manganese nodules. In the second chapter of the thesis a procedure is described for the determination of cadmium, lead, zinc and uranium in samples of Austrian mineral waters. After acidification, the sample was heated to expell CO 2 and the elements in the presence of 8-hydroxyquinoline are extracted into chloroform at pH-7. Then the metals are adsorbed on a column of the strongly basic anion-exchange resin Dowex 1 from a medium consisting of 55% chloroform, 36% methanol and 9% 12M hydrochloric acid. After simultaneous elution of the elements with 1M nitric acid, a portion of the eluate was passed through another column containing the same resin to separate uranium from the other elements. The uranium was determined fluorimetrically and cadmium, lead and zinc by atomic absorption spectroscopy. The method was successfully used for the quantitative determination of these elements in mineral water samples. (Author)

  3. SEPARATION OF EUROPIUM FROM OTHER LANTHANIDE RAE EARTHS BY SOLVENT EXTRACTION

    Science.gov (United States)

    Peppard, D.F.; Horwitz, E.P.; Mason, G.W.

    1963-02-12

    This patent deals with a process of separating europium from other lanthanides present in aqueous hydrochloric or sulfuric acid solutions. The europium is selectively reduced to the divalent state with a divalent chromium salt formed in situ from chromium(III) salt plus zinc amalgam. The other trivalent lanthanides are then extracted away from the divalent europium with a nitrogen-flushed phosphoric acid ester or a phosphonic acid ester. (AEC)

  4. Specific bile acid radioimmunoassays for separate determinations of unconjugated cholic acid, conjugated cholic acid and conjugated deoxycholic acid in serum and their clinical application

    International Nuclear Information System (INIS)

    Matern, S.; Gerok, W.

    1977-01-01

    Specific radioimmunoassays for separate determinations of serum unconjugated cholic, conjugated cholic and conjugated deoxycholic acids have been developed. Prior to the radioimmunoassay, extraction of serum bile acids was performed with Amberlite XAD-2. Unconjugated cholic acid was separated from glyco- and taurocholic acids by thin-layer chromatography. At 50% displacement of bound labeled glyco[ 3 H]cholic acid using antiserum obtained after immunization with cholic acid-bovine serum albumin-conjugate the cross-reactivity of taurocholic acid was 100%, cholic acid 80%, glycochenodeoxycholic acid 10%, chenodeoxycholic acid 7%, conjugated deoxycholic acid 3%, and conjugated lithocholic acid 3 H]cholic acid was linear on a logit-log plot from 5 to 80 pmol of unlabeled glycocholic acid. Fasting serum conjugated cholic acid in healthy subjects was 0.68 +- 0.34 μmol/l. Unconjugated cholic acid was determined by a solid phase radioimmunoassay using the cholic acid antibody chemically bound to Sepharose. The displacement curve of [ 3 H]cholic acid in the solid phase radioimmunoassay was linear on a logit-log plot from 5 to 200 pmol of unlabeled cholic acid. The coefficient of variation between samples was 5%. Fasting serum conjugated deoxycholic acid concentrations in 10 healthy subjects ranged from 0.18 to 0.92 μmol/l determined by a radioimmunoassay using antiserum obtained after immunization with deoxycholic acid-bovine serum albumin-conjugate. The clinical application of these bile acid radioimmunoassays is shown by an 'oral cholate tolerance test' as a sensitive indicator of liver function and by an 'oral cholyglycine tolerance test' as a useful test for bile acid absorption. (orig.) [de

  5. Separation of platinum metals by theirs extraction as sulfides

    International Nuclear Information System (INIS)

    Pilipenko, A.T.; Ryabushko, O.P.; Ty Van Mak

    1978-01-01

    Separation of platinum metals by means of their sediment in the form of sulfides with subsequent extraction is studied. The optimum conditions of metal sulfide extraction are determined, the metal output dependence from acidness and aqueous phase composition and also the organic solvent nature are investigated. Ruthenium concentration was determined photometrically. Ruthenium sulfide is extracted by butyl spirit from 1-4 normal hydrochloric acid. The maximum extraction grade of 63% is reached in 3.2-normal acid. When the mixture of acetic and hydrochloric acids (2:1) is used for decomposition of ruthenium tiosalts, the grade of ruthenium extraction by amyl spirit or the mixture of anyl and butyl spirits (1:1) constitutes 100%

  6. Separation and recovery of organic acids from fermented kitchen ...

    African Journals Online (AJOL)

    Organic acids produced from anaerobic digestion of kitchen waste were recovered using a new integrated method which consisted of freezing and thawing, centrifugation, filtration and evaporation. The main organic acid produced was lactic acid (98%). After the freezing and thawing process, 73% of the total suspended ...

  7. The separation of trace elements in manganese dioxide

    International Nuclear Information System (INIS)

    Jones, E.A.; Dixon, K.

    1981-01-01

    Separations from manganese are discribed for (a)Al(III), Mo(VI), V(V), and Ti(IV), and (b)trace elements in general. In the first separation, a combined anion-cation exchange, the oxalate complexes are absorbed onto the anionic BIO.RAD 1-X8 resin. V(V) and Al(III) are then eluted into a cation-exchange column from which they are eluted successively, Mo(VI) and Ti(IV) then being eluted from the anionic resin. In the second separation, up to 2g of manganese is absorbed onto BIO.RAD AG 50W-X8 resin, from which V(V) is eluted with dilute hydrochloric acid prior to the elution of Co(II), Cu(II), Zn(II), Cd(II), Fe(III), As(III), Sb(III), Mo(VI), W(VI), and Sn(II) with a mixture of 1 M hydrochloric acid, 80 per cent acetone, and 0,1 per cent hydrogen peroxide. Mn(11) is eluted next with a mixture of 0,75M hydrochloric acid and 90 per cent acetone, after which the remaining cations are eluted with 4M hydrochloric acid. Satisfactory recoveries ranging from 0,8 to 60 mg/l were obtained for 18 of the 21 elements tested. After concentration by evaporation, final measurements were made by the use of atomic-absorption spectrophotometry, or direct-reading spectrometry with excitation from an inductively coupled plasma source. Comparative results were obtained with atomic-absorption procedures where the manganese was not separated. However, the separation procedure can reduce the time required for analysis by the direct method because it limits the number of dilutions necessary and eliminates the need for the use of the method of additions to compensate for interferences from manganese

  8. The separation of U and Y by D2EHPA

    International Nuclear Information System (INIS)

    Dwi-Biyantoro; Subagiono, R.; Rosyidin; Kris-Tri-Basuki; Tri-Handini; Purwoto

    1996-01-01

    The separation of uranium and yttrium in hydrochloric acid was extracted by D 2 EHPA in dodecane. This process used liquid-liquid extraction method. The variables studied were the concentration of hydrochloric acid, the concentration of extractant, time of extraction, and the temperature of extraction. The data evaluation of the research showed that the optimum condition was as follows: the concentration of HCI = 0.2 M, the concentration of extractant = 0.15 M D 2 EHPA, the time of extraction = 15 minutes, and the temperature of extraction = 20 o C. It was found that the distribution coefficient of uranium was = 34.43, the distribution coefficient of yttrium was = 2.20, and the separation factor of U-Y= 15.65

  9. Ion exchange separation of low boric acid concentrations from water

    International Nuclear Information System (INIS)

    Kysela, J.; Brabec, J.; Peterka, F.

    1975-01-01

    Boric acid poisoning of the moderator of the TR-O experimental heavy water reactor was studied. The possibility is discussed of removing boric acid from heavy water by means of a strong basic anion exchanger, below the residual concentration of 0.01 mg B/l. Measurements of the usable capacities of the strong basic anion exchanger Zerollit FF showed that the penetration of boric acid during the sorption period does not exceed the value of 0.015 mg B/l. The dependence was found of capacity on the boric acid concentration in the solution. Analytical methods used to determine B in water are also described. (author)

  10. Bifidobacterium breve with α-linolenic acid and linoleic acid alters fatty acid metabolism in the maternal separation model of irritable bowel syndrome.

    Directory of Open Access Journals (Sweden)

    Eoin Barrett

    Full Text Available The aim of this study was to compare the impact of dietary supplementation with a Bifidobacterium breve strain together with linoleic acid & α-linolenic acid, for 7 weeks, on colonic sensitivity and fatty acid metabolism in rats. Maternally separated and non-maternally separated Sprague Dawley rats (n = 15 were orally gavaged with either B. breve DPC6330 (10(9 microorganisms/day alone or in combination with 0.5% (w/w linoleic acid & 0.5% (w/w α-linolenic acid, daily for 7 weeks and compared with trehalose and bovine serum albumin. Tissue fatty acid composition was assessed by gas-liquid chromatography and visceral hypersensitivity was assessed by colorectal distension. Significant differences in the fatty acid profiles of the non-separated controls and maternally separated controls were observed for α-linolenic acid and arachidonic acid in the liver, oleic acid and eicosenoic acid (c11 in adipose tissue, and for palmitoleic acid and docosahexaenoic acid in serum (p<0.05. Administration of B. breve DPC6330 to MS rats significantly increased palmitoleic acid, arachidonic acid and docosahexaenoic acid in the liver, eicosenoic acid (c11 in adipose tissue and palmitoleic acid in the prefrontal cortex (p<0.05, whereas feeding B. breve DPC6330 to non separated rats significantly increased eicosapentaenoic acid and docosapentaenoic acid in serum (p<0.05 compared with the NS un-supplemented controls. Administration of B. breve DPC6330 in combination with linoleic acid and α-linolenic acid to maternally separated rats significantly increased docosapentaenoic acid in the serum (p<0.01 and α-linolenic acid in adipose tissue (p<0.001, whereas feeding B. breve DPC6330 with fatty acid supplementation to non-separated rats significantly increased liver and serum docosapentaenoic acid (p<0.05, and α-linolenic acid in adipose tissue (p<0.001. B. breve DPC6330 influenced host fatty acid metabolism. Administration of B. breve DPC6330 to maternally separated

  11. Separation and recovery of organic acids from fermented kitchen ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-11-02

    Nov 2, 2009 ... Figure 1 shows the recovery process of organic acids from fermen- ted kitchen waste. ... freezing process was carried out using a deep freezer at -30°C for overnight. .... few factors which affect the production of lactic acid in the.

  12. Separation of transfer ribonucleic acids on polystyrene anion exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Singhal, R.P.; Griffin, G.D.; Novelli, G.D.

    1976-11-16

    The transfer RNA separation by chromatography on strong-base-polystyrene exchange materials is examined and compared with the widely used reversed-phase chromatography. Results indicate important differences in some transfer RNA (tRNA) elution patterns by the anion-exchange chromatography, as compared with the reversed-phase chromatography. Transfer RNAs containing hydrophobic groups are adsorbed more strongly. The anion exchanger has twice the number of theoretical plates. Single peaks of tRNA/sub 2//sup Glu/ and tRNA/sub 1//sup Phe/ obtained from the reversed-phase column give multiple peaks on polystyrene anion-exchange chromatography. All six leucine tRNAs (Escherichia coli) and differences in tRNA populations synthesized during early and late stages of the dividing lymphocytes from normal human blood can be characterized by the anion-exchange chromatography. Different separation profiles are obtained by two separation systems for tyrosine tRNAs from mouse liver and mouse-plasma-cell tumor. The results indicate that, in contrast to the reversed-phase chromatography, strong-base-polystyrene anion-exchange chromatography is capable of separating tRNAs with minor structural differences.

  13. Chromatographic separation of metal ions by means of paper treated with trioctyl - phosphate, Annex 7

    Energy Technology Data Exchange (ETDEWEB)

    Cvjeticanin, N M; Cvoric, J D; Obrenovic-Paligoric, I D [Institute of Nuclear Sciences Boris Kidric, Laboratorija za visoku aktivnost, Vinca, Beograd (Serbia and Montenegro)

    1963-12-15

    This chromatographic behaviour of uranium, thorium and some other metal ions and long-lived fission products was investigated on paper treated with trioctyl-phosphate. Hydrochloric, nitric, sulphuric and perchloric acids in concentrations of 0.1-10 N were used as the elution agents. The R{sub f} values of the ions investigated, which show the possibility of the inter separation of some cations, are given as a function of the concentration of acids (author)

  14. Selective separation of indium by iminodiacetic acid chelating resin

    International Nuclear Information System (INIS)

    Fortes, M.C.B.; Benedetto, J.S.; Martins, A.H.

    2007-01-01

    - Indium can be recovered by treating residues, flue dusts, slags, and metallic intermediates in zinc smelting. This paper investigates the adsorption characteristics of indium and iron on an iminodiacetic acid chelating resin, Amberlite R IRC748 (Rohm and Haas Co.-USA). High concentrations of iron are always present in the aqueous feed solution of indium recovery. In addition, the chemical behaviour of iron in adsorptive systems is similar to that of indium. The metal concentrations in the aqueous solution were based on typical indium sulfate leach liquor obtained from zinc hydrometallurgical processing in a Brazilian plant. The ionic adsorption experiments were carried out by the continuous column method. Amberlite R IRC748 resin had a high affinity for indium under acidic conditions. Indium ions adsorbed onto the polymeric resin were eluted with a 0.5 mol/dm 3 sulphuric acid solution passed through the resin bed in the column. 99.5% pure indium sulfate aqueous solution was obtained using the iminodiacetic acid chelating resin Amberlite R IRC748. (author)

  15. The separation and determination of fatty acids by isotopic dilution and radiogas-liquid chromatography

    International Nuclear Information System (INIS)

    Beardsley, D.A.

    1981-01-01

    A number of static phases have been evaluated for the GLC separation of fatty acids. Of those investigated, only AT 1200 was capable of resolving the isomeric forms of the acids. A radiogas-liquid chromatographic method incorporating isotopic dilution analysis has been developed for the determination of n-butyric acid. The proposed method has been applied to the determination of the acid in hydrolysed butter fat and milk chocolate extracts. (author)

  16. Possible prebiotics and gallic acid separations from jackfruit seed extract

    Directory of Open Access Journals (Sweden)

    Kulchanat Prasertsit

    2015-06-01

    Full Text Available A large amount of jackfruit seeds can be extracted for possible prebiotics and phenolics (gallic acid and purified by crystallization and solid phase extraction (SPE, respectively. The studied parameters for crystallization were mixing speed, crystallizing temperature and cooling rate while the studied parameters for SPE were feed concentration, feed flow rate and length to diameter ratio (L/D of the extraction column. The optimal condition for the crystallization provided the crystal yield of 0.028 g crystal /g dry extract at 100 rpm mixing speed, 58°C crystallizing temperature and 1°C /min cooling rate. Molecular weight analysis of the crystals indicated that the crystals can be fructo-oligosaccharide or raffinose. The optimal condition for SPE obtaining gallic acid 92 percent yield was at 4% w/v feed concentration with 3 mL/min flow rate and L/D of 15.3. Finally a high temperature can degrade both possible prebiotic and gallic acid.

  17. Process for the separation of proteins from acid whey

    Energy Technology Data Exchange (ETDEWEB)

    Mirabel, B

    1980-01-01

    Acid whey from cheese or casein manufacture (pH less than 4.6) and containing about 5.2 g protein/l is passed through a cation exchange resin (of silica coated with a copolymer of styrene/vinyltriethoxysilane carrying SO/sub 3/H functional groups). The proteins adsorbed on the resin (alpha-lactalbumin, beta-lactoglobulin, serum albumin and immunoglobulins) are eluated with an 0.1 M ammonia solution, concentrated under vacuum and freeze-dried, obtaining a final product with 88% undenatured protein. The products are for use in the food and pharmaceutical industries and for dietetic and veterinary purposes.

  18. Magnetically separable nanoferrite-anchored glutathione: Aqueous homocoupling of arylboronic acids under microwave irradiation

    Science.gov (United States)

    A highly active, stable and magnetically separable glutathione based organocatalyst provided good to excellent yields to symmetric biaryls in the homocoupling of arylboronic acids under microwave irradiation. Symmetrical biaryl motifs are present in a wide range of natural p...

  19. Separation of Am, Cm from Pm by elution chromatography with DTPA-lactic acid mixed solution

    International Nuclear Information System (INIS)

    Wei Liansheng; Zhang Zuyi; Zhong Jiahua

    1988-01-01

    The effect of various factors on the separation of Am and Cm from Pm in the cation exchange-DPTA (diethylenetiaminepenlaacetic acid)-lactic acid system is studied, such as the concentration of DTPA, pH of the eluant, temperature and flow rate. Separation results show that the recovery of Am and Cm is 99.18% and the decontamination factor of Am, Cm from Pm is 431

  20. Method for separating mono- and di-octylphenyl phosphoric acid esters

    International Nuclear Information System (INIS)

    Arnold, W.D. Jr.

    1977-01-01

    A method for separating mono-octylphenyl phosphoric acid ester and di-octylphenyl phosphoric acid ester from a mixture thereof comprises reacting the ester mixture with a source of lithium or sodium ions to form a mixture of the phosphate salts; contacting the salt mixture with an organic solvent which causes the dioctylphenyl phosphate salt to be dissolved in the organic solvent phase and the mono-octylphenyl phosphate salt to exist in a solid phase; separating the phases; recovering the phosphate salts from their respective phases; and acidifying the recovered salts to form the original phosphoric acid esters

  1. Radiochemical separation from111In from Cd and Cu by Ion exchange chromatography

    International Nuclear Information System (INIS)

    Yavari, R.; Khanchi, A. R.; Rafii, H.; Maragheh, M. G.; Farajzadeh, M. A.

    2005-01-01

    In this work, during the nuclear reaction of nat Cd (p, xn) 111 In, the irradiated cadmium target was dissolved in 3 M nitric acid. It was passed through a cation exchange column, containing 4 g. of AG 5OW-X8, and then was separated from cadmium and copper impurities by using a simple two stage procedure. At the first stage, cadmium was eluted with acetone-water-hydrobromic acid solution. At the second stage, indium was eluted with acetone-water-hydrochloric acid solution. The effluent was evaporated to dry and the residue was dissolved in 0.01M hydrochloric acid. The overall yield of the procedure was 95 ± 1 percent and the amount of cadmium and copper contamination were 0.3 and 0.1 ppm, respectively

  2. A review of physical properties of separators for valve-regulated lead/acid batteries

    Energy Technology Data Exchange (ETDEWEB)

    Zguris, G.C. [Hovosorb Separators, Hollingsworth and Vose Co., West Groton, MA (United States)

    1996-03-01

    The microglass separator has been used from the conception of valve-regulated lead/acid (VRLA) technology. There is increasing recognition that the separator has a critical role in battery performance. Research is supporting the position that compression exerted by the separator has an important role in premature capacity loss. Some companies have suggested that the separator compression set/creep plays a critical role in the battery failure mechanism in float applications. ALABC studies have shown that designs with higher compression improve the cycle life of batteries. Increasing numbers of manufacturers are designing their separators around the end-application of the battery. The separator in a VRLA battery is not an inactive spacer/barrier, as in a flooded lead/acid cell. Instead, these separators function as a key element, the third electrode. This paper reviews aspects of the microglass separator used in VRLA batteries. Information is provided to make a better separator selection, since a 100% microglass media, or any recombinant battery separator mat (RBSM) for a VRLA battery has a critical role in assuring the performance of the battery. A poor design can thus decrease the expected life of the battery. (orig.)

  3. Separation of uranium by extraction with foamed plastics

    International Nuclear Information System (INIS)

    Korkisch, J.

    1983-07-01

    Polyurethane foams are frequently used for the extraction and separation of inorganic and organic species. The attraction of the materials lies in their favourable hydrodynamic properties obviating the need for the forced-flow conditions associated with conventional chromatographic-type column packing of small particles. The research work described has been directed to providing information on the extraction and separation of uranium (and thorium) by an open-cell polyurethane foam from media containing nitrates and from hydrochloric acid systems. The influence of many different experimental parameters (concentrations, acidity, impregnation of the foam with organic extractants) on the extraction was investigated. Based on the results of these investigations two methods were developed to separate uranium from nitric acid solution and from hydrochloric acid solution, respectively. The first uses calcium or aluminium nitrate salting and foam impregnated with Aliquat 336, the second ascorbic acid addition and TOPO-impregnated foam. The methods separate uranium and thorium from each other and from most other elements and can be used analytically or in the purification of uranium from impure plant products such as yellow cake

  4. Ligand exchange chromatography for analysis and preparative separation of tritium-labelled amino acids

    International Nuclear Information System (INIS)

    Zolotarev, Yu.A.; Zaitsev, D.A.; Penkina, V.I.; Dostavalov, I.N.; Myasoedov, N.F.

    1988-01-01

    Racemic tritium-labelled amino acids were separated into optical isomers by chromatography on a chiral polyacrylamide sorbent filled with copper ions. The polyacrylamide sorbent is synthesized by Mannich's reaction through the action of formaldehyde and L-phenylalanine upon polyacrylamide Biogel P-4 in an alkali phosphate buffer. Tritium-labelled amino acids are eluted by a weak alkali solution of ammonium carbonate. Data are presented on the ligand exchange chromatography of amino acids depending on the degree to which the sorbent is filled with copper ions and on the eluent concentration. Amino acids are isolated from the eluent on short columns filled with sulfonated cation exchanger in the H + form. HPLC on modified silica gel sorbents is also used for the analysis of tritium-labelled optically active amino acids. Amino acids are eluted by a weakly acidic water-methanol solution containing ammonium acetate. UV and scintillation flow type detectors are used. (author) 7 refs.; 8 figs

  5. Separation of copper-64 from copper phthalocyanine

    International Nuclear Information System (INIS)

    Battaglin, R.I.M.

    1979-01-01

    The separation of copper-64 from irradiated copper phthalocyanine by Szilard-Chalmers effect is studied. Two methods of separation are used: one of them is based on the dissolution of the irradiated dry compound in concentrated sulfuric acid following its precipitation in water. In the other one the compound is irradiated with water in paste form following treatment with water and hydrochloric acid. The influence of the crystal form of the copper phthalocyanine on the separation yield of copper-64 is shown. Preliminary tests using the ionic exchange technique for purification and changing of copper-64 sulfate to chloride form are carried out. The specific activity using the spectrophotometric technique, after the determination of the copper concentration in solution of copper-64, is calculated. (Author) [pt

  6. Solvent extraction separations of trivalent lanthanide and actinide ions using an aqueous aminomethanediphosphonic acid

    International Nuclear Information System (INIS)

    Jensen, M. P.

    1998-01-01

    The possibility of separating the trivalent lanthanides, represented by EU 3+ , and actinides, represented by Cf 3+ , using HDEHP in toluene and an aqueous phase containing N-piperidinomethane-1,1-diphosphotic acid, PMDPA, has been investigated. This modified aqueous phase offers potential advantages over the diethylenetriaminepentaacetic acid based TALSPEAK process because of the improved complexation properties of PMDPA in acidic solutions, and the ability to decompose PMDPA before disposal. Extraction experiments were conducted at 25 C in 2 M NaClO 4 between -log [H + ] 1 and 2. The studies enabled us to derive the aqueous phase speciation, the stability constants of the aqueous complexes, and the Cf/Eu separation factors. Despite the presence of an amino group in PMDPA that should favor the retention of the actinides in the aqueous phase, the Cf/Eu separation factors are near unity under the conditions studied

  7. Optimization of methanol crystallization for highly efficient separation of palmitic acid from palm fatty acid mixture using response surface methodology

    Directory of Open Access Journals (Sweden)

    A. A.W. Japir

    2018-01-01

    Full Text Available The objective of the current study was to develop parameters for the separation of palmitic acid (PA from a crude palm oil saturated fatty acid (SFAs mixture by using the methanol crystallization method. The conditions of methanol crystallization were optimized by the response surface methodology (RSM with the D-optimal design. The procedure of developing the solvent crystallization method was based on various different parameters. The fatty acid composition was carried out using a gas chromatography flame ionization detector (GC-FID as fatty acid methyl esters. The highest percentage of SFAs was more than 96% with the percentage yield of 87.5% under the optimal conditions of fatty acids-to-methanol ratio of 1: 20 (w/v, the crystallization temperature of -15 °C, and the crystallization time of 24 hours, respectively. The composition of separated SFAs in the solid fraction contains 96.7% of palmitic acid (C16:0 as a dominant component and 3.3% of stearic acid (C18:0. The results showed that utilizing methanol as a crystallization solvent is recommended because of its high efficiency, low cost, stability, availability, comparative ease of recovery and its ability to form needle-like crystals which have good filtering and washing characteristics.

  8. Optimization of methanol crystallization for highly efficient separation of palmitic acid from palm fatty acid mixture using response surface methodology

    International Nuclear Information System (INIS)

    Japir, A.A.W.; Salimon, J.; Derawi, D.; Yahaya, B.H.; Jamil, M.S.M.; Yusop, M.R.

    2017-01-01

    The objective of the current study was to develop parameters for the separation of palmitic acid (PA) from a crude palm oil saturated fatty acid (SFAs) mixture by using the methanol crystallization method. The conditions of methanol crystallization were optimized by the response surface methodology (RSM) with the D-optimal design. The procedure of developing the solvent crystallization method was based on various different parameters. The fatty acid composition was carried out using a gas chromatography flame ionization detector (GC-FID) as fatty acid methyl esters. The highest percentage of SFAs was more than 96% with the percentage yield of 87.5% under the optimal conditions of fatty acids-to-methanol ratio of 1: 20 (w/v), the crystallization temperature of -15 °C, and the crystallization time of 24 hours, respectively. The composition of separated SFAs in the solid fraction contains 96.7% of palmitic acid (C16:0) as a dominant component and 3.3% of stearic acid (C18:0). The results showed that utilizing methanol as a crystallization solvent is recommended because of its high efficiency, low cost, stability, availability, comparative ease of recovery and its ability to form needle-like crystals which have good filtering and washing characteristics. [es

  9. SEPARATION OF HAFNIUM FROM ZIRCONIUM

    Science.gov (United States)

    Overholser, L.B.; Barton, C.J. Sr.; Ramsey, J.W.

    1960-05-31

    The separation of hafnium impurities from zirconium can be accomplished by means of organic solvent extraction. The hafnium-containing zirconium feed material is dissolved in an aqueous chloride solution and the resulting solution is contacted with an organic hexone phase, with at least one of the phases containing thiocyanate. The hafnium is extracted into the organic phase while zirconium remains in the aqueous phase. Further recovery of zirconium is effected by stripping the onganic phase with a hydrochloric acid solution and commingling the resulting strip solution with the aqueous feed solution. Hexone is recovered and recycled by means of scrubbing the onganic phase with a sulfuric acid solution to remove the hafnium, and thiocyanate is recovered and recycled by means of neutralizing the effluent streams to obtain ammonium thiocyanate.

  10. Separation of transuranium elements from high-level waste by extraction with diisodecyl phosphoric acid

    International Nuclear Information System (INIS)

    Morita, Y.; Kubota, M.; Tani, S.

    1991-01-01

    Separation of transuranic elements (TRU) by extraction with diisodecyl phosphoric acid (DIDPA) has been studied to develop a partitioning process for high-level waste (HLW). In the present study, experiments of counter-current continuous extraction and back-extraction using a miniature mixer-settler were carried out to find the optimum process condition for the separation of Np initially in the pentavalent state and to examine the extraction behaviors of fission and corrosion products. (J.P.N.)

  11. 59Ni and 63Ni separation from boric acid concentrates produced at NPP

    International Nuclear Information System (INIS)

    Fisera, O.

    2010-01-01

    Procedure for direct separation of radionickel from boric acid concentrate was developed. Quantitative separation from 100 mL of real concentrate on the column filled with 3 mL of PAN-DMG composite material was achieved. PAN-DMG material (dimethylglyoxime in porous beads of polyacrylonitrile) was compared with Ni Resin and DMG-PAN material exhibited higher sorption capacity for nickel than Ni Resin. (author)

  12. ARCA II - a new apparatus for fast, repetitive HPLC separations

    International Nuclear Information System (INIS)

    Schaedel, M.; Bruechle, W.; Jaeger, E.; Schimpf, E.; Kratz, J.V.; Scherer, U.W.; Zimmermann, H.P.

    1989-04-01

    The microcomputer controlled Automated Rapid Chemistry Apparatus, ARCA, is described in its newly designed version for the study of chemical properties of element 105 in aqueous solutions. This improved version, ARCA II, is adapted to the needs of fast and repetitive separations to be carried out in a chemically inert automated micro high performance liquid chromatography system. As an example, the separation of several group IIIB, IVB, and VB elements in the system triisooctylamine/hydrochloric acid within 30 s is demonstrated. Furthermore, a new method for the fast preparation of samples for α-particle spectroscopy by evaporation of the aqueous effluent with an intense light source is presented. (orig.)

  13. Review and assessment of technologies for the separation of cesium from acidic media

    Energy Technology Data Exchange (ETDEWEB)

    Orth, R.J.; Brooks, K.P.; Kurath, D.E.

    1994-09-01

    A preliminary literature survey has been conducted to identify and evaluate methods for the separation of cesium from acidic waste. The most promising solvent extraction, precipitation, and ion exchange methods, along with some of the attributes for each method, are listed. The main criteria used in evaluating the separation methods were as follows: (1) good potential for cesium separation must be demonstrated (i.e., cesium decontamination factors on the order of 50 to 100). (2) Good selectivity for cesium over bulk components must be demonstrated. (3) The method must show promise for evolving into a practical and fairly simple process. (4) The process should be safe to operate. (5) The method must be robust (i.e., capable of separating cesium from various acidic waste types). (6) Secondary waste generation must be minimized. (7) The method must show resistance to radiation damage. The most promising separation methods did not necessarily satisfy all of the above criteria, thus key areas requiring further development are suggested for each method. The report discusses in detail these and other areas requiring further development, as well as alternative solvent extraction, precipitation, ion exchange, and {open_quote}other{close_quote} technologies that, based on current information, show less promise for the separation of cesium from acidic wastes because of significant process limitations. When appropriate, the report recommends areas of future development.

  14. Absorptive glass-mat separators for valve-regulated lead/acid batteries - thoughts on compression

    Energy Technology Data Exchange (ETDEWEB)

    Zguris, G.C. [Hovosorb Separators, Hollingsworth and Vose Co., West Groton, MA (United States)

    1997-07-01

    In the past few years valve-regulated lead/acid (VRLA) batteries have come under increased study. Their use has become more widespread, yet their expected life has not always been realized. This paper discusses some thoughts relating to the property of compression of the microglass separator and the impact of compression on VRLA battery life. Ideas are suggested for the design engineer to consider in selecting a battery separator. Additionally, several long-term battery separator tests are described. As more is learned about the complex interactions that are taking place in the VRLA recombination process, a greater appreciation is being given to the role of the separator. Today, battery designers can help improve expected battery performance by incorporating the latest information regarding battery separators, compression factors, and impact on life. (orig.)

  15. Separation of free fatty acids from high free fatty acid crude palm oil using short-path distillation

    Science.gov (United States)

    Japir, Abd Al-Wali; Salimon, Jumat; Derawi, Darfizzi; Bahadi, Murad; Yusop, Muhammad Rahimi

    2016-11-01

    The separation of free fatty acids (FFAs) was done by using short-path distillation (SPD). The separation parameters was at their boiling points, a feed amount of 2.3 mL/min, an operating pressure of 10 Torr, a condenser temperature of 60°C, and a rotor speed of 300 rpm. The physicochemical characteristics of oil before and after SPD were determined. The results showed that FFA % of 8.7 ± 0.3 and 0.9 ± 0.1 %, iodine value of 53.1 ± 0.4 and 52.7 ± 0.5 g I2/100 g, hydroxyl value of 32.5 ± 0.6 and 13.9 ± 1.1 mg KOH/g, unsaponifiable value of 0.31 ± 0.01 and 0.20 ± 0.15%, moisture content of 0.31 ± 0.01 and 0.24 ± 0.01 % for high free fatty acid crude palm oil before and after distillation, respectively. Gas chromatography (GC) results showed that the major fatty acids in crude palm oil (CPO) were palmitic acid (44.4% - 45%) followed by oleic acid (39.6% - 39.8%). In general, high free fatty acid crude palm oil after molecular distillation (HFFA-CPOAM) showed admirably physicochemical properties.

  16. Large-scale separation of amino acids by continuous displacement chromatography

    Energy Technology Data Exchange (ETDEWEB)

    DeCarli, J.P. II; Carta, G.; Byers, C.H.

    1989-10-01

    Continuous annular chromatography (CAC) is a developing technology that allows truly continuous chromatographic separations. Previous work has demonstrated the utility of this technology for the separation of various materials by isocratic elution on a bench scale. Novel applications and improved operation of the process were studied in this work, demonstrating that CAC is a versatile apparatus which is capable of separations at high throughput. Three specific separation systems were investigated. Pilot-scale separations at high loadings were performed using an industrial sugar mixture as an example of scale-up for isocratic separations. Bench-scale experiments of a low concentration metal ion mixture were performed to demonstrate stepwise elution, a chromatographic technique which decreases dilution and increases sorbent capacity. Finally, the separation of mixtures of amino acids by ion exchange was investigated to demonstrate the use of displacement development on the CAC. This technique, which perhaps has the most potential, when applied to the CAC allowed simultaneous separation and concentration of multicomponent mixtures on a continuous basis. Mathematical models were developed to describe the CAC performance and optimize the operating conditions. For all the systems investigated, the continuous separation performance of the CAC was found to be very nearly the same as the batchwise performance of conventional chromatography. The technology appears, thus, to be very promising for industrial applications.

  17. A broad look at separator material technology for valve-regulated lead/acid batteries

    Energy Technology Data Exchange (ETDEWEB)

    Zguris, G.C. [Hollingsworth and Vose, West Groton, MA (United States)

    1998-05-18

    Recent research has proved the importance of a constant force of 40 kPa or greater on the paste solidus-grid interface. This has lead to increased interest in re-examining the microglass separator and the system that the plate-separator interaction forms. This renewed interest has resulted in new separator ideas and the revisiting of concepts tried in the early days of valve-regulated lead/acid (VRLA) technology. The paper is divided into two parts. The first part examines some past separator developments that have been tried but are presently not accepted by the general VRLA community. This is due to the excellent performance of the microglass separator used so successfully during the last 20 years. Many fundamental questions that need to be asked regarding the selection of a new separator system have long ago been forgotten. The second part of the paper reviews some fundamental aspects of separator selection, and some important attributes that the separator must provide based on current knowledge of the separator system. Attributes such as toughness, corrosion resistance, compression, wicking, stratification, porosity and conformability are discussed. (orig.)

  18. cis,cis-Muconic acid: separation and catalysis to bio-adipic acid for nylon-6,6 polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Vardon, Derek R.; Rorrer, Nicholas A.; Salvachúa, Davinia; Settle, Amy E.; Johnson, Christopher W.; Menart, Martin J.; Cleveland, Nicholas S.; Ciesielski, Peter N.; Steirer, K. Xerxes; Dorgan, John R.; Beckham, Gregg T.

    2016-01-01

    cis,cis-Muconic acid is a polyunsaturated dicarboxylic acid that can be produced renewably via the biological conversion of sugars and lignin-derived aromatic compounds. Subsequently, muconic acid can be catalytically converted to adipic acid -- the most commercially significant dicarboxylic acid manufactured from petroleum. Nylon-6,6 is the major industrial application for adipic acid, consuming 85% of market demand; however, high purity adipic acid (99.8%) is required for polymer synthesis. As such, process technologies are needed to effectively separate and catalytically transform biologically derived muconic acid to adipic acid in high purity over stable catalytic materials. To that end, this study: (1) demonstrates bioreactor production of muconate at 34.5 g L-1 in an engineered strain of Pseudomonas putida KT2440, (2) examines the staged recovery of muconic acid from culture media, (3) screens platinum group metals (e.g., Pd, Pt, Rh, Ru) for activity and leaching stability on activated carbon (AC) and silica supports, (4) evaluates the time-on-stream performance of Rh/AC in a trickle bed reactor, and (5) demonstrates the polymerization of bio-adipic acid to nylon-6,6. Separation experiments confirmed AC effectively removed broth color compounds, but subsequent pH/temperature shift crystallization resulted in significant levels of Na, P, K, S and N in the crystallized product. Ethanol dissolution of muconic acid precipitated bulk salts, achieving a purity of 99.8%. Batch catalysis screening reactions determined that Rh and Pd were both highly active compared to Pt and Ru, but Pd leached significantly (1-9%) from both AC and silica supports. Testing of Rh/AC in a continuous trickle bed reactor for 100 h confirmed stable performance after 24 h, although organic adsorption resulted in reduced steady-state activity. Lastly, polymerization of bio-adipic acid with hexamethyldiamine produced nylon-6,6 with comparable properties to its petrochemical counterpart

  19. Separation of fatty acid methyl esters by GC-online hydrogenation × GC.

    Science.gov (United States)

    Delmonte, Pierluigi; Fardin-Kia, Ali Reza; Rader, Jeanne I

    2013-02-05

    The separation of fatty acid methyl esters (FAME) provided by a 200 m × 0.25 mm SLB-IL111 capillary column is enhanced by adding a second dimension of separation ((2)D) in a GC × GC design. Rather than employing two GC columns of different polarities or using different elution temperatures, the separation in the two-dimensional space is achieved by altering the chemical structure of selected analytes between the two dimensions of separation. A capillary tube coated with palladium is added between the first dimension of separation ((1)D) column and the cryogenic modulator, providing the reduction of unsaturated FAMEs to their fully saturated forms. The (2)D separation is achieved using a 2.5 m × 0.10 mm SLB-IL111 capillary column and separates FAMEs based solely on their carbon skeleton. The two-dimensional separation can be easily interpreted based on the principle that all the saturated FAMEs lie on a straight diagonal line bisecting the separation plane, while the FAMEs with the same carbon skeleton but differing in the number, geometric configuration or position of double bonds lie on lines parallel to the (1)D time axis. This technique allows the separation of trans fatty acids (FAs) and polyunsaturated FAs (PUFAs) in a single experiment and eliminates the overlap between PUFAs with different chain lengths. To our knowledge, this the first example of GC × GC in which a chemical change is instituted between the two dimensions to alter the relative retentions of components and identify unsaturated FAMEs.

  20. Separation and purification of hyaluronic acid by glucuronic acid imprinted microbeads

    Energy Technology Data Exchange (ETDEWEB)

    Akdamar, H.Acelya; Sarioezlue, Nalan Yilmaz [Department of Biology, Anadolu University, Eskisehir (Turkey); Ozcan, Ayca Atilir; Ersoez, Arzu [Department of Chemistry, Anadolu University, Eskisehir (Turkey); Denizli, Adil [Department of Chemistry, Hacettepe University, Ankara (Turkey); Say, Ridvan, E-mail: rsay@anadolu.edu.tr [Department of Chemistry, Anadolu University, Eskisehir (Turkey); BIBAM (Plant, Drug and Scientific Researches Center), Anadolu University, Eskisehir (Turkey)

    2009-05-05

    The purification of hyaluronic acid (HA) is relatively significant to use in biomedical applications. The structure of HA is formed by the repetitive units of glucuronic acid and N-acetyl glucosamine. In this study, glucuronic acid-imprinted microbeads have been supplied for the purification of HA from cell culture (Streptococcus equi). Histidine-functional monomer, methacryloylamidohistidine (MAH) was chosen as the metal-complexing monomer. The glucuronic acid-imprinted poly(ethyleneglycoldimethacrylate-MAH-Copper(II)) [p(EDMA-MAH-Cu{sup 2+})] microbeads have been synthesized by typical suspension polymerization procedure. The template glucuronic acid has been removed by employing 5 M methanolic KOH solution. p(EDMA-MAH-Cu{sup 2+}) microbeads have been characterized by elemental analysis, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) images and swelling studies. Moreover, HA adsorption experiments have been performed in a batch experimental set-up. Purification of HA from cell culture supernatant has been also investigated by determining the hyaluronidase activity using purified HA as substrate. The glucuronic acid imprinted p(EDMA-MAH-Cu{sup 2+}) particles can be used many times with no significant loss in adsorption capacities. Also, the selectivity of prepared molecular imprinted polymers (MIP) has been examined. Results have showed that MIP particles are 19 times more selective for glucuronic acid than N-acetylglucose amine.

  1. Phase Engineering of Perovskite Materials for High-Efficiency Solar Cells: Rapid Conversion of CH3NH3PbI3 to Phase-Pure CH3NH3PbCl3 via Hydrochloric Acid Vapor Annealing Post-Treatment.

    Science.gov (United States)

    Zhou, Weiran; Zhou, Pengcheng; Lei, Xunyong; Fang, Zhimin; Zhang, Mengmeng; Liu, Qing; Chen, Tao; Zeng, Hualing; Ding, Liming; Zhu, Jun; Dai, Songyuan; Yang, Shangfeng

    2018-01-17

    Organometal halide CH 3 NH 3 PbI 3 (MAPbI 3 ) has been commonly used as the light absorber layer of perovskite solar cells (PSCs), and, especially, another halide element chlorine (Cl) has been often incorporated to assist the crystallization of perovskite film. However, in most cases, a predominant MAPbI 3 phase with trace of Cl - is obtained ultimately and the role of Cl involvement remains unclear. Herein, we develop a low-cost and facile method, named hydrochloric acid vapor annealing (HAVA) post-treatment, and realize a rapid conversion of MAPbI 3 to phase-pure MAPbCl 3 , demonstrating a new concept of phase engineering of perovskite materials toward efficiency enhancement of PSCs for the first time. The average grain size of perovskite film after HAVA post-treatment increases remarkably through an Ostwald ripening process, leading to a denser and smoother perovskite film with reduced trap states and enhanced crystallinity. More importantly, the generation of MAPbCl 3 secondary phase via phase engineering is beneficial for improving the carrier mobility with a more balanced carrier transport rate and enlarging the band gap of perovskite film along with optimized energy level alignment. As a result, under the optimized HAVA post-treatment time (2 min), we achieved a significant enhancement of the power conversion efficiency (PCE) of the MAPbI 3 -based planar heterojunction-PSC device from 14.02 to 17.40% (the highest PCE reaches 18.45%) with greatly suppressed hysteresis of the current-voltage response.

  2. Analytical and preparative separation of organic acids from water by extraction with trioctylamine

    International Nuclear Information System (INIS)

    Eberle, S.H.; Hoyer, O.; Knobel, K.P.; Hodenberg, S. von

    1977-12-01

    The extraction of pure organic acids and of humic and ligninsulfonic acid from water by a solution of trioctylamine in chloroform was investigated (technical grade amine = ALAMINE). Quantitative separation is achieved by double extraction with 5% ALAMINE at pH 3,5 - 4. The acids may be back-extracted with dilute sodium hydroxide solution. Procedures are described for the analytical extraction of water samples of 200 to 2.000 ml and for the flow-through processing of large water volumes. (orig.) [de

  3. Separation of aliphatic carboxylic acids and benzenecarboxylic acids by ion-exclusion chromatography with various cation-exchange resin columns and sulfuric acid as eluent.

    Science.gov (United States)

    Ohta, Kazutoku; Ohashi, Masayoshi; Jin, Ji-Ye; Takeuchi, Toyohide; Fujimoto, Chuzo; Choi, Seong-Ho; Ryoo, Jae-Jeong; Lee, Kwang-Pill

    2003-05-16

    The application of various hydrophilic cation-exchange resins for high-performance liquid chromatography (sulfonated silica gel: TSKgel SP-2SW, carboxylated silica gel: TSKgel CM-2SW, sulfonated polymethacrylate resin: TSKgel SP-5PW, carboxylated polymethacrylate resins: TSKgel CM-5PW and TSKgel OA-Pak A) as stationary phases in ion-exclusion chromatography for C1-C7 aliphatic carboxylic acids (formic, acetic, propionic, butyric, isovaleric, valeric, isocaproic, caproic, 2-methylhexanoic and heptanoic acids) and benzenecarboxylic acids (pyromellitic, trimellitic, hemimellitic, o-phthalic, m-phthalic, p-phthalic, benzoic, salicylic acids and phenol) was carried out using diluted sulfuric acid as the eluent. Silica-based cation-exchange resins (TSKgel SP-2SW and TSKgel CM-2SW) were very suitable for the ion-exclusion chromatographic separation of these benzenecarboxylic acids. Excellent simultaneous separation of these benzenecarboxylic acids was achieved on a TSKgel SP-2SW column (150 x 6 mm I.D.) in 17 min using a 2.5 mM sulfuric acid at pH 2.4 as the eluent. Polymethacrylate-based cation-exchange resins (TSKgel SP-5PW, TSKgel CM-5PW and TSKgel OA-Pak A) acted as advanced stationary phases for the ion-exclusion chromatographic separation of these C1-C7 aliphatic carboxylic acids. Excellent simultaneous separation of these C1-C7 acids was achieved on a TSKgel CM-5PW column (150 x 6 mm I.D.) in 32 min using a 0.05 mM sulfuric acid at pH 4.0 as the eluent.

  4. SEPARATION OF T-MAZ ETHOXYLATED SORBITAN FATTY ACID ESTERS BY SUPERCRITICAL FLUID CHROMATOGRAPHY

    Science.gov (United States)

    The application of supercritical fluid chromatography (SFC) to the analysis of T-MAZ ethoxylated sorbitan fatty acid esters is described. FC separation methods utilize a density programming technique and a 50 um I.D. capillary column. his work demonstrates that capillary column S...

  5. Microsystems for anion exchange separation of radionuclides in nitric acid media

    Energy Technology Data Exchange (ETDEWEB)

    Losno, M.; Brennetot, R.; Mariet, C. [DEN/Service d' Etudes Analytiques et de Reactivite des Surfaces - SEARS, CEA, Centre de Saclay, Universite Paris-Saclay, F-91191, Gif sur Yvette (France); Ferrante, I.; Descroix, S. [MMBM Group, Institut Curie Research Center, CNRS UMR 168, Paris (France)

    2016-07-01

    An efficient and reproducible photo-polymerized poly(ethylene glycol methacrylate methacrylate-co- allyl methacrylate) monolith was synthesized and a photo-grafting process based on the ene-thiol click-chemistry has been performed to give anion exchange properties to the monolith. Since their introduction in the early 1990's polymethacrylate monoliths have emerged as a powerful alternative for microscale separations or sample treatment. Their relatively simple implementation in columns with small internal diameters makes them particularly attractive for the new chromatographic challenges of complex matrices analysis and on-chip separations. Despite their relatively poor ion-exchange capacity due to their highly porous structure, their use as anion exchangers is of large interest for nuclear analysis as numerous separations are based on this process. This paper presents a systematic study of the synthesis of the polymeric porous monolith and the versatile and robust functionalization method developed for the specific strong acidic media used in radiochemical procedures. The robustness of the stationary phase was tested in concentrated nitric acid. It appears that the C-S bond formed via thiol-ene chemistry is strong enough to be used to graft function of interest for separation in strong nitric acid medium. The photo-grafted anion exchanger, a quaternary ammonium, presents sufficient resistance to be used for radionuclide separation in [HNO{sub 3}]=5 mol.L{sup -1}so the next step is its integration in the cyclo olefin copolymer (COC) micro-system.

  6. Dissolution Kinetics of Icel-Aydincik Dolomite in Hydrochloric Acid

    African Journals Online (AJOL)

    NJD

    Department of Mining Engineering, Faculty of Engineering and Architecture, Cukurova University, Balcali, ... 65 °C. It was observed that heterogeneous chemical reactions ..... Dolomite, Ph.D. thesis, Cukurova University, Adana, Turkey, 2004.

  7. The development of 126Sn separation procedure by means of TBP resin

    International Nuclear Information System (INIS)

    Andris, Boris; Bena, Jozef

    2016-01-01

    Separation possibilities of 126 Sn with a new extraction-chromatographic material TBP Resin were studied. Suitable conditions for tin separation were determined in hydrochloric acid medium. 126 Sn was concentrated on TBP resin from 6 mol L -1 HCl and was eluted with 0.1 mol L -1 HCl. A purification step to remove 137 Cs with AMP-PAN column was necessary to obtain sufficiently purified samples which were directly measured with gamma spectrometry for 126 Sn activity. Separation of 126 Sn from a raw sludge sample was done according to proposed procedure, 126 Sn was detected and its activity was determined. (author)

  8. Separation of hafnium from zirconium in sulfuric acid solutions using pressurized ion exchange

    International Nuclear Information System (INIS)

    Hurst, F.J.

    1981-01-01

    High-resolution pressurized ion exchange has been used successfully to study and separate hafnium and zirconium sulfate complexes by chromatographic elution from Dowex 50W-X8 (15 to 25 μm) resin with sulfuric acid solutions. Techniques were developed to continuously monitor the column effluents for zirconium and hafnium by reaction with fluorometric and colorimetric reagents. Since neither reagent was specific for either metal ion, peak patterns were initially identified by using the stable isotopes 90 Zr and 180 Hf as fingerprints of their elution position. Distribution ratios for both zirconium and hafnium decrease as the inverse fourth power of the sulfuric acid concentration below 2N and as the inverse second power at higher acid concentration. The hafnium-to-zirconium separation factor is approximately constant (approx. 8) over the 0.5 to 3N range. Under certain conditions, an unseparated fraction was observed that was not retained by the resin. The amount of this fraction which is thought to be a polymeric hydrolysis product appears to be a function of metal and sulfuric acid concentrations. Conditions are being sought to give the highest zirconium concentration and the lowest acid concentration that can be used as a feed material for commercial scale-up in the continuous annular chromatographic (CAC) unit without formation of the polymer

  9. Recovery and separation of rare-earth elements, barium, and strontium from bastnasite with sulfuric acid

    International Nuclear Information System (INIS)

    Eisele, J.A.; Bauer, D.J.

    1974-01-01

    A bench-scale investigation was made of a concentrated H 2 SO 4 reaction for recovering and separating rare earth elements, barium, and strontium from a bastnaesite ore and byproduct. Barium and strontium were dissolved in the concentrated acid and precipitated as a mixed product by water dilution. Separation of strontium from barium was effected by reaction with Na 2 CO 3 solution, followed by a dilute acid leach of the SrCO 3 formed. After removing the barium and strontium from bastnaesite ore, the rare-earth elements were roasted to water-soluble sulfates. The rare earth sulfate solution was subsequently processed by solvent extraction to produce rare-earth oxides low in lead and magnesium. (U.S.)

  10. Study of a dense metal membrane reactor for hydrogen separation from hydroiodic acid decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Tosti, Silvano; Borelli, Rodolfo; Borgognoni, Fabio [ENEA, Dipartimento FPN, C.R. ENEA Frascati, Via E. Fermi 45, Frascati, Roma I-00044 (Italy); Favuzza, Paolo; Tarquini, Pietro [ENEA, Dipartimento TER, C.R. ENEA Casaccia, Via Anguillarese 301, Roma (Italy); Rizzello, Claudio [Tesi Sas, Via Bolzano 28, Roma (Italy)

    2008-10-15

    A membrane reactor has been studied for separating the hydrogen produced by the dissociation of hydroiodic acid in the thermochemical-sulfur iodine process. A dense metal membrane tube of wall thickness 0.250 mm has been considered in this analysis for hosting a fixed-bed catalyst: the selective separation of hydrogen from an azeotropic H{sub 2}O-HI mixture has been studied in the temperature range of 700-800 K. The materials being considered for the construction of the membrane tube are niobium and tantalum; as a matter of fact, the most commonly used Pd-Ag membranes cannot withstand the corrosive environment generated by the hydroiodic acid. The Damkohler-Peclet analysis has been used for designing the membrane reactor, while a finite element method has simulated its behaviour: the effect of the temperature and pressure on the HI conversion and hydrogen yield has been evaluated. (author)

  11. Separation of glycols from dilute aqueous solutions via complexation with boronic acids

    Energy Technology Data Exchange (ETDEWEB)

    Randel, L.A.; King, C.J.

    1991-07-01

    This work examines methods of separating low molecular weight glycols from dilute aqueous solution. Extraction into conventional solvents is generally not economical, since, in the literature reviewed, distribution ratios for the two- to four-carbon glycols are all less than one. Distribution ratios can be increased, however, by incorporating into the organic phase an extracting agent that will complex with the solute of interest. The extracting agent investigated in this work is 3-nitrophenylboronic acid (NPBA). NPBA, a boric acid derivative, reversibly complexes with many glycols. The literature on complexation of borate and related compounds with glycols, including mechanistic data, measurement techniques, and applications to separation processes, provides information valuable for designing experiments with NPBA and is reviewed herein. 88 refs., 15 figs., 24 tabs.

  12. Effect of hydrocarbon radical length of fatty acid collectors on flotation separation process of thorium ions

    International Nuclear Information System (INIS)

    Skrylev, L.D.; Perlova, O.V.; Sazonova, V.F.

    1991-01-01

    It is shown experimentally that the degree of flotation separation of thorium ions collected by their means increases firstly (potassium laurate), then decreases (potassium tridecanate) and after that increases again (potassium palminate) when increasing the length of the hydrocarbon radical of potassium soaps of saturated fatty acids. The first increase of the collector efficiency is due to the decrease of solubility of thorium-containing sublates, and drop and further increase is due to the change in colloidchemical properties of sublates

  13. The selective conversion of glutamic acid in amino acid mixtures using glutamate decarboxylase--a means of separating amino acids for synthesizing biobased chemicals.

    Science.gov (United States)

    Teng, Yinglai; Scott, Elinor L; Sanders, Johan P M

    2014-01-01

    Amino acids (AAs) derived from hydrolysis of protein rest streams are interesting feedstocks for the chemical industry due to their functionality. However, separation of AAs is required before they can be used for further applications. Electrodialysis may be applied to separate AAs, but its efficiency is limited when separating AAs with similar isoelectric points. To aid the separation, specific conversion of an AA to a useful product with different charge behavior to the remaining compounds is desired. Here the separation of L-aspartic acid (Asp) and L-glutamic acid (Glu) was studied. L-Glutamate α-decarboxylase (GAD, Type I, EC 4.1.1.15) was applied to specifically convert Glu into γ-aminobutyric acid (GABA). GABA has a different charge behavior from Asp therefore allowing a potential separation by electrodialysis. Competitive inhibition and reduced operational stability caused by Asp could be eliminated by maintaining a sufficiently high concentration of Glu. Immobilization of GAD does not reduce the enzyme's initial activity. However, the operational stability was slightly reduced. An initial study on the reaction operating in a continuous mode was performed using a column reactor packed with immobilized GAD. As the reaction mixture was only passed once through the reactor, the conversion of Glu was lower than expected. To complete the conversion of Glu, the stream containing Asp and unreacted Glu might be recirculated back to the reactor after GABA has been removed. Overall, the reaction by GAD is specific to Glu and can be applied to aid the electrodialysis separation of Asp and Glu. © 2014 American Institute of Chemical Engineers.

  14. Review and assessment of technologies for the separation of strontium from alkaline and acidic media

    International Nuclear Information System (INIS)

    Orth, R.J.; Kurath, D.E.

    1994-01-01

    A literature survey has been conducted to identify and evaluate methods for the separation of strontium from acidic and alkaline media as applied to Hanford tank waste. The most promising methods of solvent extraction, precipitation, and ion exchange are described. The following criteria were used for evaluating the separation methods: Appreciable strontium removal must be demonstrated; Strontium selectivity over bulk components must be demonstrated; The method must show promise for evolving into a practical and fairly simple process; The process should be safe to operate; The method must be robust (i.e., capable of separating strontium from various waste types); Secondary waste generation must be minimized; and The method must show resistance to radiation damage. The methods discussed did not necessarily satisfy all of the above criteria; thus, key areas requiring further development are also given for each method. Less promising solvent extraction, precipitation, and ion exchange methods were also identified; areas for potential development are included in this report

  15. Separation and accumulation of acitinides with the aid of a phosphoric acid polymer

    International Nuclear Information System (INIS)

    Novikov, A.; Geckeler, K.E.

    1993-01-01

    A new method for the separation and enrichment of actinides based on the use of polymer reagents is presented, in this study, poly(ethyleneimine methylphosphonic acid) was used for the interaction with actinide ions in the homogeneous phase. In conjunction with membrane filtration this reagent allows both the separation and the enrichment of actinides from dilute solutions. The retention profiles for the series of actinides U(VI), Np(V), Pu(IV), Am(III), Cm(III), Cf(III) were investigated at different pH. Retention differences between 0% and 100% were found depending on the actinide element and pH. Thus, these elements can be separated and enriched form aqueous solutions of binary or multi-component mixtures. (orig.)

  16. Boronic Acid-Based Approach for Separation and Immobilization of Glycoproteins and Its Application in Sensing

    Directory of Open Access Journals (Sweden)

    Lin Liu

    2013-10-01

    Full Text Available Glycoproteins influence a broad spectrum of biological processes including cell-cell interaction, host-pathogen interaction, or protection of proteins against proteolytic degradation. The analysis of their glyco-structures and concentration levels are increasingly important in diagnosis and proteomics. Boronic acids can covalently react with cis-diols in the oligosaccharide chains of glycoproteins to form five- or six-membered cyclic esters. Based on this interaction, boronic acid-based ligands and materials have attracted much attention in both chemistry and biology as the recognition motif for enrichment and chemo/biosensing of glycoproteins in recent years. In this work, we reviewed the progress in the separation, immobilization and detection of glycoproteins with boronic acid-functionalized materials and addressed its application in sensing.

  17. Chiral separation of amino acids in biological fluids by micellar electrokinetic chromatography with laser-induced fluorescence detection.

    Science.gov (United States)

    Thorsén, G; Bergquist, J

    2000-08-18

    A method is presented for the chiral analysis of amino acids in biological fluids using micellar electrokinetic chromatography (MEKC) and laser-induced fluorescence (LIF). The amino acids are derivatized with the chiral reagent (+/-)-1-(9-anthryl)-2-propyl chloroformate (APOC) and separated using a mixed micellar separation system. No tedious pre-purification of samples is required. The excellent separation efficiency and good detection capabilities of the MEKC-LIF system are exemplified in the analysis of urine and cerebrospinal fluid. This is the first time MEKC has been reported for chiral analysis of amino acids in biological fluids. The amino acids D-alanine, D-glutamine, and D-aspartic acid have been observed in cerebrospinal fluid, and D-alanine and D-glutamic acid in urine. To the best of our knowledge no measurements of either D-alanine in cerebrospinal fluid or D-glutamic acid in urine have been presented in the literature before.

  18. Synergistic effects on enantioselectivity of zwitterionic chiral stationary phases for separations of chiral acids, bases, and amino acids by HPLC.

    Science.gov (United States)

    Hoffmann, Christian V; Pell, Reinhard; Lämmerhofer, Michael; Lindner, Wolfgang

    2008-11-15

    In an attempt to overcome the limited applicability scope of earlier proposed Cinchona alkaloid-based chiral weak anion exchangers (WAX) and recently reported aminosulfonic acid-based chiral strong cation exchangers (SCX), which are conceptionally restricted to oppositely charged solutes, their individual chiral selector (SO) subunits have been fused in a combinatorial synthesis approach into single, now zwitterionic, chiral SO motifs. The corresponding zwitterionic ion-exchange-type chiral stationary phases (CSPs) in fact combined the applicability spectra of the parent chiral ion exchangers allowing for enantioseparations of chiral acids and amine-type solutes in liquid chromatography using polar organic mode with largely rivaling separation factors as compared to the parent WAX and SCX CSPs. Furthermore, the application spectrum could be remarkably expanded to various zwitterionic analytes such as alpha- and beta-amino acids and peptides. A set of structurally related yet different CSPs consisting of either a quinine or quinidine alkaloid moiety as anion-exchange subunit and various chiral or achiral amino acids as cation-exchange subunits enabled us to derive structure-enantioselectivity relationships, which clearly provided strong unequivocal evidence for synergistic effects of the two oppositely charged ion-exchange subunits being involved in molecular recognition of zwitterionic analytes by zwitterionic SOs driven by double ionic coordination.

  19. Ultraviolet-absorbing organic anions in uremic serum separated by capillary zone electrophoresis, and quantification of hippuric acid

    NARCIS (Netherlands)

    Schoots, A.C.; Verheggen, T.P.E.M.; Vries, de P.M.J.M.; Everaerts, F.M.

    1990-01-01

    Organic anions accumulated in blood serum of patients with chronic renal failure were separated by a novel technique: closed-system capillary zone electrophoresis (CZE) in a pH6 carrier-electrolyte system. Hippuric acid (HA), p-hydroxyhippuric acid, and uric acid were identified by their co-elution

  20. On-Chip Microfluidic Components for In Situ Analysis, Separation, and Detection of Amino Acids

    Science.gov (United States)

    Zheng, Yun; Getty, Stephanie; Dworkin, Jason; Balvin, Manuel; Kotecki, Carl

    2013-01-01

    The Astrobiology Analytical Laboratory at GSFC has identified amino acids in meteorites and returned cometary samples by using liquid chromatography-electrospray ionization time-of-flight mass spectrometry (LCMS). These organic species are key markers for life, having the property of chirality that can be used to distinguish biological from non-biological amino acids. One of the critical components in the benchtop instrument is liquid chromatography (LC) analytical column. The commercial LC analytical column is an over- 250-mm-long and 4.6-mm-diameter stainless steel tube filled with functionized microbeads as stationary phase to separate the molecular species based on their chemistry. Miniaturization of this technique for spaceflight is compelling for future payloads for landed missions targeting astrobiology objectives. A commercial liquid chromatography analytical column consists of an inert cylindrical tube filled with a stationary phase, i.e., microbeads, that has been functionalized with a targeted chemistry. When analyte is sent through the column by a pressurized carrier fluid (typically a methanol/ water mixture), compounds are separated in time due to differences in chemical interactions with the stationary phase. Different species of analyte molecules will interact more strongly with the column chemistry, and will therefore take longer to traverse the column. In this way, the column will separate molecular species based on their chemistry. A lab-on-chip liquid analysis tool was developed. The microfluidic analytical column is capable of chromatographically separating biologically relevant classes of molecules based on their chemistry. For this analytical column, fabrication, low leak rate, and stationary phase incorporation of a serpentine microchannel were demonstrated that mimic the dimensions of a commercial LC column within a 5 10 1 mm chip. The microchannel in the chip has a 75- micrometer-diameter oval-shaped cross section. The serpentine

  1. Preparative separation of chlorogenic acid by centrifugal partition chromatography from highbush blueberry leaves (Vaccinium corymbosum L.).

    Science.gov (United States)

    Kim, Sang-Min; Shang, Ya Fang; Um, Byung-Hun

    2010-01-01

    Blueberries (genus Vaccinium) have gained worldwide focus because of the high anthocyanin content of their fruits. In contrast, the leaves of blueberry have not attracted any attention, even though they contain large quantities of chlorogenic acid, a strong antioxidant compound. The aim of this investigation was the quantification and preparative isolation of chlorogenic acid (5-caffeoylquinic acid, 5-CQA) from blueberry leaves using a new separation scheme, centrifugal partition chromatography (CPC). A water fraction containing a high concentration of 5-CQA (14.5% of dry weight extract) was obtained by defatting a crude methanol extract from blueberry leaves. CPC was applied to isolate 5-CQA from this water fraction using a two-phase solvent system of ethyl acetate-ethanol-water at a volume ratio 4:1:5 (v/v/v). The flow-rate of mobile phase was 2 mL/min with the ascending mode while rotating at 1200 rpm. The eluate was monitored at 330 nm. The structure of chlorogenic acid in the CPC fraction was confirmed with HPLC, UV, ESI/MS and NMR spectra. The HPLC chromatogram showed that the fractions collected by CPC contained chlorogenic acid with 96% purity based on peak area percentage. The total amount of chlorogenic acid isolated from 0.5 g of a water fraction was 52.9 mg, corresponding to 10.6% of the water fraction. The isolated compound was identified successively as 5-CQA with MS (parent ion at m/z 355.1 [M + H](+)) and (1)H NMR spectra [caffeoyl moiety in the down field (δ 6.0-8.0 ppm) and quinic acid moiety in the up field (δ 2.0-5.5 ppm)]. 5-CQA was successfully isolated from blueberry leaves by the CPC method in a one-step procedure, indicating a further potential use for blueberry leaves. Copyright © 2010 John Wiley & Sons, Ltd.

  2. CZE separation of strawberry anthocyanins with acidic buffer and comparison with HPLC.

    Science.gov (United States)

    Comandini, Patrizia; Blanda, Giampaolo; Cardinali, Andrea; Cerretani, Lorenzo; Bendini, Alessandra; Caboni, Maria Fiorenza

    2008-10-01

    Anthocyanins, the major colourants of strawberries, are polar pigments that are positively charged at low pH. Herein, we have assessed a new analytical method for the separation of anthocyanins using CZE. Acidic buffer solutions (pH pigments in the cation flavylium form and achieve high molar absorptivity at 510 nm. These spectral properties enabled us to identify strawberry anthocyanins in a preliminary stage by detection in the visible range, although the method was optimised at 280 nm to obtain the best S/N. The effects of buffer composition highlighted the necessity of adding an organic modifier to the running buffer to obtain a suitable separation. The electrophoretic method permitted the separation of the three main anthocyanins of strawberry extracts, namely pelargonidin 3-glucoside (Pg-glu), pelargonidin 3-rutinoside and cyanidin 3-glucoside. The electrophoretic results, expressed as retention time and separation efficiency of the major anthocyanin (Pg-glu), were compared to those achieved in HPLC, the analytical technique traditionally used for the investigation of anthocyanins in vegetable matrix. The content of Pg-glu in strawberries (cv. Camarosa), calculated with HPCE and HPLC methods, resulted respectively in 11.41 mg/L and 11.37 mg/L.

  3. Comparison of GC stationary phases for the separation of fatty acid methyl esters in biodiesel fuels.

    Science.gov (United States)

    Goding, Julian C; Ragon, Dorisanne Y; O'Connor, Jack B; Boehm, Sarah J; Hupp, Amber M

    2013-07-01

    The fatty acid methyl ester (FAME) content of biodiesel fuels has traditionally been determined using gas chromatography with a polar stationary phase. In this study, a direct comparison of the separation of FAMEs present in various biodiesel samples on three polar stationary phases and one moderately polar stationary phase (with comparable column dimensions) was performed. Retention on each column was based on solubility in and polarity of the phase. Quantitative metrics describing the resolution of important FAME pairs indicate high resolution on all polar columns, yet the best resolution, particularly of geometric isomers, is achieved on the cyanopropyl column. In addition, the separation of four C18 monounsaturated isomers was optimized and the elution order determined on each column. FAME composition of various biodiesel fuel types was determined on each column to illustrate (1) chemical differences in biodiesels produced from different feedstocks and (2) chemical similarities in biodiesels of the same feedstock type produced in different locations and harvest seasons.

  4. Influence of modifiers on the separation of dysprosium from neodymium using organophosphorus acid derivates

    Energy Technology Data Exchange (ETDEWEB)

    Elwert, Tobias; Schwarz, Sabrina; Goldmann, Daniel [TU Clausthal, Clausthal-Zellerfeld (Germany). Lehrstuhl fuer Rohstoffaufbereitung und Recycling

    2016-01-15

    The aim of this study was to investigate the applicability of three organophosphorus acid derivates (D2EHPA, EHEHPA and Cyanex 572) for the separation of terbium and dysprosium from praseodymium and neodymium from NdFeB magnets in chloride solution. A special focus was put on the effect of phase modifiers. The investigations revealed that all extractants show in general a similar extraction behavior but the extraction is shifted to higher pH values in the order D2EHPA < EHEHPA < Cyanex 572. Therefore, and due to higher realizable loadings, EHEHPA and Cyanex 572 are more suitable for the investigated separation problem than D2EHPA. Whereas EHEHPA requires 1-decanol as phase modifier, Cyanex 572 can be employed without modifier addition.

  5. Facile Separation of 5-O-Galloylquinic Acid from Chinese Green Tea Extract using Mesoporous Zirconium Phosphate.

    Science.gov (United States)

    Ma, Yilong; Shang, Yafang; Zhu, Danye; Wang, Caihong; Zhong, Zhifeng; Xu, Ziyang

    2016-05-01

    5-O-Galloylquinic acid from green tea and other plants is attracting increasing attention for its antioxidant and antileishmanial bioactivities. It is always isolated using a silica column, a Sephadex column and high-performance liquid chromatography (HPLC) methods, which are either laborious or instrument dependent. To develop a new method to easily separate 5-O-galloylquinic acid. Mesoporous zirconium phosphate (m-ZrP) was prepared to conveniently separate 5-O-galloylquinic acid from Chinese green tea extract, and the target compound was easily obtained by simple steps of adsorption, washing and desorption. The effects of the green tea extraction conditions, extract concentrations, and m-ZrP adsorption/desorption dynamics on the 5-O-galloylquinic acid separation were evaluated. 5-O-Galloylquinic acid that was separated from a 70% ethanol extract of green tea was of moderate HPLC purity (92%) and recovery (88%), and an increased non-specific binding of epigallocatechin gallate (EGCG) on m-ZrP was observed in the diluted tea extract. The times for maximal adsorption of 5-O-galloylquinic acid in 70% ethanol extract and maximal desorption of 5-O-galloylquinic acid in 0.4% phosphoric acid solution were confirmed as 7 h and 5 h, respectively. A facile method to separate 5-O-galloylquinic acid from Chinese green tea extract using m-ZrP was established. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  6. Separation of water and oil by poly (acrylic acid)-coated stainless steel mesh prepared by radiation crosslinking

    Energy Technology Data Exchange (ETDEWEB)

    Nho, Young Chang; Shin, Jung Woong; Park, Jong Seok; Lim, Young Mook; Jeun, Joon Pyo; Kang, Phil Hyun [Research Division for Industry and Environment, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2015-05-15

    The stainless steel mesh coated with poly(acrylic acid) hydrogel was fabricated and applied for the separation of water and oil. The stainless steel mesh was immersed in aqueous poly (acrylic acid) solution, and then irradiated by radiation to introduce poly(acrylic acid) hydrogel on the surface of mesh by crosslinking. It was possible to separate oil and water from mixtures of oil/water effectively using the hydrogel-coated mesh. The effect of irradiation dose, coating thickness, size of mesh on the separation efficiency was examined.

  7. Improved separation of conjugated fatty acid methyl esters by silver ion-high-performance liquid chromatography.

    Science.gov (United States)

    Sehat, N; Rickert, R; Mossoba, M M; Kramer, J K; Yurawecz, M P; Roach, J A; Adlof, R O; Morehouse, K M; Fritsche, J; Eulitz, K D; Steinhart, H; Ku, Y

    1999-04-01

    Operating from one to six silver ion-high-performance liquid chromatography (Ag+-HPLC) columns in series progressively improved the resolution of the methyl esters of conjugated linoleic acid (CLA) isomeric mixtures from natural and commercial products. In natural products, the 8 trans, 10 cis-octadecadienoic (18:2) acid was resolved from the more abundant 7 trans, 9 cis-18:2, and the 10 trans, 12 cis-18:2 was separated from the major 9 cis, 11 trans-18:2 peak. In addition, both 11 trans, 13 cis-18:2 and 11 cis, 13 trans-18:2 isomers were found in natural products and were separated; the presence of the latter, 11 cis, 13 trans-18:2, was established in commercial CLA preparations. Three Ag+-HPLC columns in series appeared to be the best compromise to obtain satisfactory resolution of most CLA isomers found in natural products. A single Ag+-HPLC column in series with one of several normal-phase columns did not improve the resolution of CLA isomers as compared to that of the former alone. The 20:2 conjugated fatty acid isomers 11 cis, 13 trans-20:2 and 12 trans, 14 cis-20:2, which were synthesized by alkali isomerization from 11 cis, 14 cis-20:2, eluted in the same region of the Ag+-HPLC chromatogram just before the corresponding geometric CLA isomers. Therefore, CLA isomers will require isolation based on chain length prior to Ag+-HPLC separation. The positions of conjugated double bonds in 20:2 and 18:2 isomers were established by gas chromatography-electron ionization mass spectrometry as their 4,4-dimethyloxazoline derivatives. The double-bond geometry was determined by gas chromatography-direct deposition-Fourier transform infrared spectroscopy and by the Ag+-HPLC relative elution order.

  8. Separation of 2-aminobenzoic acid-derivatized glycosaminoglycans and asparagine-linked glycans by capillary electrophoresis.

    Science.gov (United States)

    Sato, Kae; Sato, Kiichi; Okubo, Akira; Yamazaki, Sunao

    2005-01-01

    A capillary electrophoresis method was developed for the analysis of oligosaccharides combined with derivatization with 2-aminobenzoic acid. Glycosaminoglycan delta-disaccharides were effectively resolved on a fused-silica capillary tube using 150 mM borate, pH 8.5, as a running electrolyte solution. This analytical method was applied to the identification of glycosaminoglycan in combination with enzymatic digestion. The separation of N-glycans or glucose-oligomers was performed with a phosphate buffer containing polyethylene glycol or borate as an electrolyte solution. This method is expected to be useful in the determination of oligosaccharide structures in a glycoprotein.

  9. Electrochemical properties of polyolefin nonwoven fabric modified with carboxylic acid group for battery separator

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Seong-Ho; Kang, Hae-Jeong; Ryu, Eun-Nyoung; Lee, Kwang-Pill E-mail: kplee@kyungpook.ac.kr

    2001-07-01

    Carboxylic acid group was introduced by radiation-induced grafting of acrylic acid (AAc) onto polyolefine nonwoven fabric (PNF), wherein the PNF comprises at least about 60% of a polyethylene having a melting temperature at {approx}132 deg. C and no more than about 40% of a second polypropylene having a lower melting temperature at {approx}162 deg. C, for a battery separator. The AAc-grafted PNF was characterized by XPS, SEM, DSC, TGA and porosimeter. The wetting speed, electrolyte retention, electrical resistance, and tensile strength were evaluated after grafting of AAc. It was found that the wetting speed, electrolyte retention, thickness, and ion-exchange capacity increased, whereas the electrical resistance decreased with increasing grafting yield. The tensile strength decreased with increasing grafting yield, whereas the elongation decreased with increasing grafting yield. (author)

  10. Electrochemical properties of polyolefine nonwoven fabric modified with carboxylic acid group for battery separator

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Seong-Ho; Park, Keung-Shik; Kang, Hae-Jeong; Ryu, Eun-Nyoung; Lee, Pill-Kwang [Department of Chemistry Graduate School, Kyungpook National University, Taegu (Korea)

    2000-07-01

    Carboxylic acid group was introduced by radiation-induced grafting of acrylic acid (AAc) onto polyolefine nonwoven fabric (PNF), wherein the PNF comprises at least about 60% of a polyethylene having a melting temperature at {approx}132degC and no more than about 40% of a second polypropylene having a lower melting temperature at {approx}162degC, for a battery separator. The AAc-grafted PNF was characterized by XPS, SEM, DSC, TGA and porosimeter. The wetting speed, electrolyte retention, electrical resistance, and tensile strength were evaluated after grafting of AAc. It was found that the wetting speed, electrolyte retention, thickness, and ion-exchange capacity increased, whereas the electrical resistance decreased with increasing grafting yield. The tensile strength decreased with increasing grafting yield, whereas the elongation decreased with increasing grafting yield. (author)

  11. A method of sample preparation for N15 determination in amino acids separated by paper chromatography

    International Nuclear Information System (INIS)

    Secer, M.

    1988-01-01

    The amino acids separated with two dimensional paper chromatography were isolated in two ways which make their 15 N determination possible 1) After developing the spots of chromatograms with ninhydrin they were cut out and shaken 30' with 2 ml dist. H 2 O. To destroy the ninhydrin-NH 3 colour complex, the extraction solution was heated in boiling waterbath for 10' and then 0.5 ml 2 N HCl was added to the solution and continued to heat for further 10'. For the 15 N determination of amino acids by emissionspectrometer this colour complex must be destroyed completely. It was reached with adding 2 ml 30% H 2 O 2 to the solution and heating it 5' in 100 0 C waterbath. After the evaporation of colourless solution under IR-lamp at 70 0 C, the white powder was dissolved with 50 ul dist. H 2 O and centrifuged 10'. The clear supernatant was used to gain N 2 gas by the CuO/CaO combustion. N 2 gas is necessary for the 15 N/ 14 N ratio determination by emissionsspectrometer. 2) In the second way, the destroying of ninhydrin-NH 3 colour complex was easier and quicker this way the spots were eluted (extracted) with 50% alcohol and 30% H 2O2 with 1:1 ratio. After shaking the solution 30', it turns quite colourless. It means that the ninhydrin-NH 3 colour complex was completely destroyed. Further works have been done as described in the first way. We have found out that one amino acid should have 10-20 ug N in it to assess the 15 N enrichment. In order to attain this quantity of N for certain amino acids, the spots of three separately run chromatograms were combined

  12. Electrochemical membrane reactor: In situ separation and recovery of chromic acid and metal ions

    International Nuclear Information System (INIS)

    Khan, Jeeshan; Tripathi, Bijay P.; Saxena, Arunima; Shahi, Vinod K.

    2007-01-01

    An electrochemical membrane reactor with three compartments (anolyte, catholyte and central compartment) based on in-house-prepared cation- and anion-exchange membrane was developed to achieve in situ separation and recovery of chromic acid and metal ions. The physicochemical and electrochemical properties of the ion-exchange membrane under standard operating conditions reveal its suitability for the proposed reactor. Experiments using synthetic solutions of chromate and dichromate of different concentrations were carried out to study the feasibility of the process. Electrochemical reactions occurring at the cathode and anode under operating conditions are proposed. It was observed that metal ion migrated through the cation-exchange membrane from central compartment to catholyte and OH - formation at the cathode leads to the formation of metal hydroxide. Simultaneously, chromate ion migrated through the anion-exchange membrane from central compartment to the anolyte and formed chromic acid by combining H + produced their by oxidative water splitting. Thus a continuous decay in the concentration of chromate and metal ion was observed in the central compartment, which was recovered separately in the anolyte and catholyte, respectively, from their mixed solution. This process was completely optimized in terms of operating conditions such as initial concentration of chromate and metal ions in the central compartment, the applied cell voltage, chromate and metal ion flux, recovery percentage, energy consumption, and current efficiency. It was concluded that chromic acid and metal ions can be recovered efficiently from their mixed solution leaving behind the uncharged organics and can be reused as their corresponding acid and base apart from the purifying water for further applications

  13. Uracil in formic acid hydrolysates of deoxyribonucleic acid

    Science.gov (United States)

    Schein, Arnold H.

    1966-01-01

    1. When DNA is hydrolysed with formic acid for 30min. at 175° and the hydrolysate is chromatographed on paper with propan-2-ol–2n-hydrochloric acid, in addition to expected ultraviolet-absorbing spots corresponding to guanine, adenine, cytosine and thymine, an ultraviolet-absorbing region with RF similar to that of uracil can be detected. Uracil was separated from this region and identified by its spectra in acid and alkali, and by its RF in several solvent systems. 2. Cytosine, deoxyribocytidine and deoxyribocytidylic acid similarly treated with formic acid all yielded uracil, as did a mixture of deoxyribonucleotides. 3. Approx. 4% of deoxyribonucleotide cytosine was converted into uracil by the formic acid treatment. ImagesFig. 1. PMID:5949371

  14. Sequential enzymatic synthesis and separation of 13N-L-glutamic acid and 13N-L-alanine

    International Nuclear Information System (INIS)

    Cohen, M.B.; Spolter, L.; MacDonald, M.; Chang, C.C.; Takahashi, J.

    1975-01-01

    The sequential enzymatic synthesis and separation of 13 N-L-glutamic acid and 13 N-L-alanine are described. Basically, that involves the synthesis of 13 N-L-glutamic acid by one enzyme, the transamination of the labeled glutamic acid to form 13 N-L-alanine by a second enzyme, and the separation of the two amino acids by rapid column chromatography. The 13 N-L-alanine was evaluated in animals by imaging and tissue distribution studies and showed good potential as a pancreatic imaging agent

  15. Liquid-liquid phase separation in internally mixed magnesium sulfate/glutaric acid particles

    Science.gov (United States)

    Wu, Feng-Min; Wang, Xiao-Wei; Jing, Bo; Zhang, Yun-Hong; Ge, Mao-Fa

    2018-04-01

    The confocal Raman microscopy is utilized to investigate the liquid-liquid phase separation (LLPS) of mixed magnesium sulfate/glutaric acid (MgSO4/GA) droplets deposited on a hydrophobic polytetrafluoroethylene (PTFE) substrate and a hydrophilic quartz substrate. Raman spectra collected from different regions of the mixed droplets provide detailed information of component distributions for MgSO4 and GA. During the dehydration process, the MgSO4/GA mixed particles show the initial liquid-liquid phase separation between 85% and 80% relative humidity (RH) on both the hydrophobic and hydrophilic substrates. For the droplets deposited on the two substrates, the inner phase of droplets is dominated by aqueous MgSO4, which is surrounded by a rich GA organic layer due to the surface tension effects. In addition, the crystallization of GA could be observed in the organic aqueous phase while it is inhibited in the inner MgSO4 phase due to the effects of gel formation of MgSO4 at low RH. The Raman spectra reveal that with decreasing RH the morphology of the mixed droplet evolves from a uniform droplet to the structure of LLPS with the GA crystallizing in the outer layer and MgSO4 gel formed in the inner phase. These findings contribute to the further understanding of the role of interactions between inorganic salts and organic acids on the morphological evolution and environmental effects of atmospheric aerosols under ambient RH conditions.

  16. The removal of uranium from acidic media using ion exchange and/or extraction chromatography

    International Nuclear Information System (INIS)

    FitzPatrick, J.R.; Schake, B.S.; Murphy, J.; Holmes, K.; West, M.H.

    1996-06-01

    The separation and purification of uranium from either nitric acid or hydrochloric acid media can be accomplished by using either solvent extraction or ion-exchange. Over the past two years at Los Alamos, emerging programs are focused on recapturing the expertise required to do limited, small-quantity processing of enriched uranium. During this period of time, we have been investigating ion-addition, waste stream polishing is associated with this effort in order to achieve more complete removal of uranium prior to recycle of the acid. Extraction chromatography has been demonstrated to further polish the uranium from both nitric and hydrochloric acid media thus allowing for a more complete recovery of the actinide material and creation of less waste during the processing steps

  17. Studies on Benzo-DODA encapsulated polymeric beads for separation of Pu from acidic solution

    International Nuclear Information System (INIS)

    Singh, K.K.; Panja, S.; Kumar, M.; Ruhela, R.; Tripathi, S.C.; Singh, A.K.; Hubli, R.C.; Bajaj, P.N.

    2014-01-01

    High level liquid waste (HLLW) generated during the reprocessing of spent fuel contains a few mg of Pu per litre of waste volume. Therefore, there is a need for selective separation of Pu from above solution as well as other such acidic waste streams. The widely used technology for separation and recovery of metal ions from radioactive wastes is liquid-liquid extraction.Though, such technologies play major role in all the bulk separation processes, they have marked limitations involving the losses of extractant in aqueous phase, third phase problems at higher metal loading, etc. These limitations have necessitated the exploration of advance, more efficient and technically feasible alternatives. In this regard it is thought that solid-liquid based Extractant Encapsulated Polymeric Beads (EEPBs) may solve some of the problems. Benzodioxodiamide (BenzoDODA) is a recently reported extractant for the separation of plutonium from radioactive waste, containing nitric acid. BenzoDODA extractant encapsulated polymeric beads were prepared by phase inversion technique and found to be quite stable as no significant structural deformation or leaching out of the extractant was observed in 4.0 M HNO 3 solution, up to studied equilibration time of 8 days. These beads have been characterized by FT-IR, TGA and SEM techniques to gain insight into their structure and morphology. Morphology and porosity of the beads, as studied by the SEM analysis, indicate that the surface of the beads is quite rough, and has enough porosity. Thermo gravimetric analysis of the synthesized composite beads shows a weight loss of ∼74% during the heating from room temperature to 120℃, due to the loss of water present in the swollen beads. Such high water content also confirms that the beads have enough porosity for efficient exchange of metal ions.The synthesized beads were evaluated, for their ability to absorb Pu from acidic solution. The kinetics measurement showed that about 45 min of

  18. Effect of complexing reagents on the ionization constant of boric acid and its relation to isotopic exchange separation factor

    International Nuclear Information System (INIS)

    Sharma, B.K.; Subramanian, R.; Mathur, P.K.

    1991-01-01

    The effect of change in concentration of complexing reagents having two or more hydroxyl groups, viz., ethylene glycol, propylene glycol, dextrose and mannitol on the ionization constant of boric acid has been studied by pH-metric titration method. The effect of increase in ionization constant of boric acid on isotopic exchange separation factor for the separation of isotopes of boron by ion exchange chromatography has been studied by the batch method. (author). 9 refs

  19. Synthesis of Homoveratric Acid-Imprinted Polymers and Their Evaluation as Selective Separation Materials

    Directory of Open Access Journals (Sweden)

    Mariusz Dana

    2011-05-01

    Full Text Available A bulk polymerization method was used to easily and efficiently prepare homo-veratric acid (3,4-dimethoxyphenylacetic acid-imprinted polymers from eight basic monomers: 2-vinylpyridine, 4-vinylpyridine, 1-vinylimidazole, N-allylaniline, N-allylpiperazine, allylurea, allylthiourea, and allylamine, in the presence of homoveratric acid as a template in N,N-dimethylformamide as a porogen. The imprinted polymer prepared from allylamine had the highest affinity to the template, showing an imprinting factor of 3.43, and allylamine polymers MIP8/NIP8 were selected for further studies. Their binding properties were analyzed using the Scatchard method. The results showed that the imprinted polymers have two classes of heterogeneous binding sites characterized by two pairs of Kd, Bmax values: Kd(1 = 0.060 μmol/mL, Bmax(1 = 0.093 μmol/mg for the higher affinity binding sites, and Kd(2 = 0.455 μmol/mL, Bmax(2 = 0.248 μmol/mg for the lower affinity binding sites. Non-imprinted polymer has only one class of binding site, with Kd = 0.417 μmol/mL and Bmax = 0.184 μmol/mg. A computational analysis of the energies of the prepolymerization complexes was in agreement with the experimental results. It showed that the selective binding interactions arose from cooperative three point interactions between the carboxylic acid and the two methoxy groups in the template and amino groups in the polymer cavities. Those results were confirmed by the recognition studies performed with the set of structurally related compounds. Allylamine polymer MIP8 had no affinity towards biogenic amines. The obtained imprinted polymer could be used for selective separation of homoveratric acid.

  20. Selective adsorption of benzhydroxamic acid on fluorite rendering selective separation of fluorite/calcite

    Science.gov (United States)

    Jiang, Wei; Gao, Zhiyong; Khoso, Sultan Ahmed; Gao, Jiande; Sun, Wei; Pu, Wei; Hu, Yuehua

    2018-03-01

    Fluorite, a chief source of fluorine in the nature, usually coexists with calcite mineral in ore deposits. Worldwide, flotation techniques with a selective collector and/or a selective depressant are commonly preferred for the separation of fluorite from calcite. In the present study, an attempt was made to use benzhydroxamic acid (BHA) as a collector for the selective separation of fluorite from calcite without using any depressant. Results obtained from the flotation experiments for single mineral and mixed binary minerals revealed that the BHA has a good selective collecting ability for the fluorite when 50 mg/L of BHA was used at pH of 9. The results from the zeta potential and X-ray photoelectron spectroscopy (XPS) indicated that the BHA easily chemisorbs onto the fluorite as compared to calcite. Crystal chemistry calculations showed the larger Ca density and the higher Ca activity on fluorite surface mainly account for the selective adsorption of BHA on fluorite, leading to the selective separation of fluorite from calcite. Moreover, a stronger hydrogen bonding with BHA and the weaker electrostatic repulsion with BHA- also contribute to the stronger interaction of BHA species with fluorite surface.

  1. Development of a field-suitable test method to evaluate the danger of hydrogen embrittlement due to hydrochloric acid pickling bathes and comparison of the effectiveness of pickling inhibitors; Entwicklung eines praxisgeeigneten Pruefverfahrens zur Bewertung des Wasserstoffgefaehrdungspotenzials von Salzsaeurebeizen und zum Vergleich der Wirksamkeit von Inhibitoren

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder-Rentrop, I.; Landgrebe, R.; Berger, C.; Hasselmann, U. [Institut fuer Werkstoffkunde, Staatliche Materialpruefungsanstalt Darmstadt, TU Darmstadt, Grafenstrasse 2, 64283 Darmstadt (Germany)

    2005-11-01

    Within the scope of the before hot dip galvanizing necessary treatment in pickling bathes, which are mostly run with hydrochloric acid the possibility of development of atomic hydrogen on the steel surface is given. The subsequent described trials aimed at making the process of hot dip galvanizing of high tensile fasteners, which are possibly susceptible of cracking due to influences of hydrogen because of their high tensile strength, more controllable under aspects of quality assurance and possibly improve the process. The field-suitable test method for process monitoring of inhibited pickling bathes is realized by tension tests. The test method works with locking rings according to DIN 471 in a specially developed tensioning device. The safety of the indication of the test method is proved by the comparison of the results with those achieved with other test methods achieved with the same pickling bathes. The ''safety of iteration'' of the developed test method is proved by similar results of trials with samples from different charges of production and heat treatment. As a consequence the tension test is qualified as test method for the field. In addition it requires little time and expenses, is easy to handle and has a robust and fault-tolerant construction. With the testing scheme developed during the project it is moreover possible to evaluate capaciously the effectiveness of inhibitors for the pickling of high-tensile fasteners. (Abstract Copyright [2005], Wiley Periodicals, Inc.) [German] Bei der im Rahmen einer Feuerverzinkung notwendigen Beizbehandlung, die zumeist in Salzsaeure vorgenommen wird, kann es zur Entwicklung von atomarem Wasserstoff an der Stahloberflaeche kommen. Ziel der nachfolgend dargestellten Untersuchungen war, den Prozess der Feuerverzinkung von hochfesten Schrauben, die aufgrund der geforderten hohen Zugfestigkeiten in einem sproedbruchanfaelligen Werkstoffzustand vorliegen koennen, insbesondere unter Aspekten der

  2. [Analyze nanofiltration separation rule of chlorogenic acid from low concentration ethanol by Donnan effect and solution-diffusion effect].

    Science.gov (United States)

    Li, Cun-Yu; Liu, Li-Cheng; Jin, Li-Yang; Li, Hong-Yang; Peng, Guo-Ping

    2017-07-01

    To separate chlorogenic acid from low concentration ethanol and explore the influence of Donnan effect and solution-diffusion effect on the nanofiltration separation rule. The experiment showed that solution pH and ethanol volume percent had influences on the separation of chlorogenic acid. Within the pH values from 3 to 7 for chlorogenic acid in 30% ethanol, the rejection rate of chlorogenic acid was changed by 70.27%. Through the response surface method for quadratic regression model, an interaction had been found in molecule weight cut-off, pH and ethanol volume percent. In fixed nanofiltration apparatus, the existence states of chlorogenic acid determinedits separation rules. With the increase of ethanol concentration, the free form chlorogenic acid was easily adsorbed, dissolved on membrane surface and then caused high transmittance due to the solution-diffusion effect. However, at the same time, due to the double effects of Donnan effect and solution-diffusion effect, the ionic state of chlorogenic acid was hard to be adsorbed in membrane surface and thus caused high rejection rate. The combination of Box-Behnken design and response surface analysis can well optimize the concentrate process by nanofiltration, and the results showed that nanofiltration had several big advantages over the traditional vacuum concentrate technology, meanwhile, and solved the problems of low efficiency and serious component lossesin the Chinese medicines separation process for low concentration organic solvent-water solution. Copyright© by the Chinese Pharmaceutical Association.

  3. Feasibility of isotachochromatography as a method for the preparative separation of weak acids and weak bases. I. Theoretical considerations

    NARCIS (Netherlands)

    Kooistra, C.; Sluyterman, L.A.A.E.

    1988-01-01

    The fundamental equation of isotachochromatography, i.e., isotachophoresis translated into ion-exchange chromatography, has been derived for weak acids and weak bases. Weak acids are separated on strong cation exchangers and weak bases on strong anion exchangers. According to theory, the elution

  4. Preparative separation and purification of rosmarinic acid from perilla seed meal via combined column chromatography.

    Science.gov (United States)

    Tang, Weizhuo; Sun, Baoshan; Zhao, Yuqing

    2014-02-01

    In this study, the preparative separation and purification of rosmarinic acid (RA) from perilla seed meal (PSM), which is a by-product of edible oil production, was achieved using combined column chromatography over macroporous and polyamide resins. To optimize the RA enrichment process, the performance and separation characteristics of nine selected macroporous resins with different chemical and physical properties were investigated. SP825 resin was the most effective: the content of RA increased from 0.27% in the original extract to 16.58% in the 50% ethanol fraction (a 61.4-fold increase). During further purification treatment on polyamide resin, 90.23% pure RA could be obtained in the 70% ethanol fraction. RA with a higher purity (>95%) could also be easily obtained using one crystallization operation. The proposed method is simple, easily operated, cost-effective, and environmentally friendly and is suitable for both large-scale RA production and waste management. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Separation and purification of γ-aminobutyric acid from fermentation broth by flocculation and chromatographic methodologies.

    Science.gov (United States)

    Gao, Qiang; Duan, Qiang; Wang, Depei; Zhang, Yunze; Zheng, Chunyang

    2013-02-27

    To date, the multifunctional γ-aminobutyric acid (GABA) is mainly produced by microbial fermentation in industry. The purpose of this study was to find an effective method for separation and purification of 31.2 g/L initial GABA from the fermentation broth of Enterococcus raffinosus TCCC11660. To remove the impurities from fermentation broth, flocculation pretreatment using chitosan and sodium alginate was first implemented to facilitate subsequent filtration. Ultrafiltration followed two discontinuous diafiltration steps to effectively remove proteins and macromolecular pigments, and the resulting permeate was further decolored by DA201-CII resin at a high decoloration ratio and GABA recovery. Subsequently, ion exchange chromatography (IEC) with Amberlite 200C resin and gradient elution were applied for GABA separation from glutamate and arginine. Finally, GABA crystals of 99.1% purity were prepared via warm ethanol precipitation twice. Overall, our results reveal that the successive process including flocculation, filtration, ultrafiltration, decoloration, IEC, and crystallization is promising for scale-up GABA extraction from fermentation broth.

  6. Separation and concentration of lead, uranium and copper using polystyrene resins functionalised with azobenzylphosphonic acid ligands

    International Nuclear Information System (INIS)

    Ueda, Kazumasa; Sato, Yuko; Yoshimura, Osamu; Yamamoto, Yoshikazu

    1988-01-01

    Two polystyrene resins functionalised with azobenzylphosphonic acid ligands were synthesised and applications for the concentration, separation and determination of micro- or milligram concentrations of metal ions were studied. Physical and chemical properties such as specific mass, water content and ion-exchange capacity were measured and the characteristics of the resins were examined. The resins were especially useful for the concentration of Pbsup(II), Usup(VI) and Cusup(II) by batch and column operations, and effective separations of Pbsup(II) from Group VIII and IIB ions could be achieved by selecting the eluents. Trace amounts of Pbsup(II), Usup(VI), Cusup(II), Mnsup(II), Znsup(II) and Fesup(III) were quantitatively retained on the resin columns at neutral pH and easily recovered by elution with 2M HCl and 2M HNO 3 . The resins were successfully applied to the concentration of trace amounts of metals in river and sea waters prior to spectroscopic determinations. (author)

  7. Effects of brief milling and acid treatment on two ordered and disordered kaolinite structures

    Czech Academy of Sciences Publication Activity Database

    Valášková, M.; Barabaszová, K.; Hundáková, M.; Ritz, M.; Plevová, Eva

    2011-01-01

    Roč. 54, č. 1 (2011), s. 70-76 ISSN 0169-1317 R&D Projects: GA ČR GA105/08/1398 Grant - others:GA ČR(CZ) GA205/09/0352 Institutional research plan: CEZ:AV0Z30860518 Keywords : kaolinite * milling * hydrochloric acid Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.474, year: 2011 http://www.sciencedirect.com/science/article/pii/S0169131711002675

  8. Comparison of alkali fusion and acid digestion methods for radiochemical separation of Uranium from dietary samples

    International Nuclear Information System (INIS)

    Kamesh Viswanathan, B.; Arunachalam, Kantha D.; Sathesh Kumar, A.; Jayakrishana, K.; Shanmugamsundaram, H.; Rao, D.D.

    2014-01-01

    Several methods exist for separation and measurement of uranium in dietary samples such as neutron activation analysis (NAA), alpha spectrometric determination, inductively coupled plasma mass spectrometry (ICP-MS) and fluorimetry. For qualitative determination of activity, NAA and alpha spectrometry are said to be superior to evaluate the isotopes of uranium ( 238 U, 234 U and 235 U). In case of alpha spectrometry, the samples have to undergo radiochemical analysis for separation from other elements for uranium detection. In our studies, uranium was determined in food matrices by acid digestion (AD) and alkali fusion (AF) methods. The recovery yield of uranium in food matrices was compared in order to get consistent yield. The average activity levels of 238 U and 234 U in food samples were calculated based on recovery yield of 232 U in the samples. The average recovery of 232 U in AD method was 22 ± 8% and in AF method, it was 14.9 ± 1.3%. The spread is more in AD method than the AF method from their mean. The lowest recovery of 232 U was found in AF method. This is due to the interference of other elements in the sample during electroplating. Experimental results showed that the uranium separation by AD method has better recovery than the AF method. The consistency in recovery of 232 U was better for AF method, which was lower than the AD method. However, overall for both the methods, the recovery can be termed as poor and need rigorous follow up studies for consistently higher recoveries (>50%) in these type of biological samples. There are reports indicating satisfactory recoveries of around 80% with 232 U as tracer in the food matrices

  9. Anaerobic digestion of glucose with separated acid production and methane formation

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, R J; Zoetemeyer, R J; Van Deursen, A; Van Andel, J G

    1979-01-01

    In a two-phase anaerobic-digestion system, with separate reactors for the acidification and methane fermentation phases, the glucose of a 1% glucose solution was almost completely converted into biomass and gases. The acid reactor was operated at 30/sup 0/C and a pH of 6.0, with a retention time of 10 h. The main products of the acid-forming phase were hydrogen, carbon dioxide, butyrate and acetate. On a molar base, these products represented over 96% of all products formed. On average, 12% of the COD content of the influent was evolved as hydrogen. The effluent of the first reactor was pumped to the methane reactor after passing through a storage vessel. The methane reactor was operated at 30/sup 0/C, pH 7.8 and a retention time of 100 h. Approximately 98% of the organic substances fed to this reactor were converted to methane, carbon dioxide and biomass. About 11% of the glucose fed to the digesting system was converted to bacterial mass.

  10. Anaerobic digestion of gucose with separated acid production and methane formation

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, A; Zoetemeyer, R J; van Deursen, A; van Andel, J G

    1979-01-01

    In a two-phase anaerobic-digestion system, with separate reactors for the acidification phase and the methane fermentation phase, the Universiteit van Amsterdam found the glucose of a 1% glucose solution (sucrose/starch-containing wastewater from agricultural industries) to be almost completely converted into biomass and gases. The acid reactor was operated at 86/sup 0/F (30/sup 0/C) and pH 6.0, with a retention time of 10 hr. The main products of the acid-forming phase were hydrogen, carbon dioxide, butyrate, and acetate. On a molar base, these products represented over 96% of all products formed. On the average, 12% of the chemical-oxygen-demand content of the influent was evolved as hydrogen. The effluent of the first reactor went to the methane reactor after passing through a storage vessel. The methane reactor operated at 86/sup 0/F (30/sup 0/C), pH 7.8, and a retention time of 100 hr. Approximately 98% of the organic substances fed to this reactor was converted to methane, carbon dioxide, and biomass. About 11% of the glucose fed to the digesting system was converted to bacterial mass.

  11. Effect of temperature on acid-base equilibria in separation techniques. A review.

    Science.gov (United States)

    Gagliardi, Leonardo G; Tascon, Marcos; Castells, Cecilia B

    2015-08-19

    Studies on the theoretical principles of acid-base equilibria are reviewed and the influence of temperature on secondary chemical equilibria within the context of separation techniques, in water and also in aqueous-organic solvent mixtures, is discussed. In order to define the relationships between the retention in liquid chromatography or the migration velocity in capillary electrophoresis and temperature, the main properties of acid-base equilibria have to be taken into account for both, the analytes and the conjugate pairs chosen to control the solution pH. The focus of this review is based on liquid-liquid extraction (LLE), liquid chromatography (LC) and capillary electrophoresis (CE), with emphasis on the use of temperature as a useful variable to modify selectivity on a predictable basis. Simplified models were evaluated to achieve practical optimizations involving pH and temperature (in LLE and CE) as well as solvent composition in reversed-phase LC. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Separating natural acidity from anthropogenic acidification in the spring flood of northern Sweden

    International Nuclear Information System (INIS)

    Laudon, Hjalmar

    2000-01-01

    Spring flood is an occasion for transient hydrochemical changes that profoundly effect the biodiversity of the aquatic ecosystem. Spring flood is also very susceptible to anthropogenic acidification. Belief that acid deposition is primarily responsible for pH decline during spring flood has been an important factor in the decision to spend close to one billion Swedish crowns to lime surface waters in northern Sweden during the last decade. The objective of this work is to present an operational tool, the Boreal Dilution Model (BDM), for separating and quantifying the anthropogenic and natural contributions to episodic acidification during spring flood episodes in northern Sweden. The limited data requirements of 10-15 stream water samples before and during spring flood make the BDM suitable for widespread use in environmental monitoring programs. This creates a possibility for distinguishing trends and spatial patterns in the human impact as well as natural pH decline. The results from applying the BDM, and a one point 'pBDM' version of the model, in northern Sweden demonstrate that the anthropogenic component associated with spring flood episodes is now generally limited. Instead it is the combination of natural organic acidity and dilution of the buffering capacity that is the major driving mechanism of episodic acidity during spring flood events in the region. While the anthropogenic component of episodic acidification generally contributes 0.1 to 0.3 pH units to the natural pH decline of up to 2.5 pH units, the current regional extent of areas that are severely affected by anthropogenically driven episodes is approximately 6%. Prior to the initiation of the Swedish Environmental Protection Agency's 'Episode Project' the limited spring flood data together with lack of a systematic methodology for determining liming candidates forced the liming authorities to base the remediation strategy in northern Sweden on biological indications. But, since there are more

  13. Chiral separation of dansyl amino acids in capillary electrophoresis using mono-(3-methyl-imidazolium)-beta-cyclodextrin chloride as selector.

    Science.gov (United States)

    Tang, Weihua; Ong, Teng Teng; Ng, Siu-Choon

    2007-06-01

    Enantioseparations of fourteen dansyl amino acids were achieved by using a positively-charged single-isomer beta-cyclodextrin, mono-(3-methyl-imidazolium)-beta-cyclodextrin chloride, as a chiral selector. Separation parameters such as buffer pH, selector concentration, separation temperature, and organic modifier were investigated for the enantioseparation in order to achieve the maximum possible resolution. Chiral separation of dansyl amino acids was found to be highly dependent on pH since the degree of protonation of these amino acids can alter the strength of electrostatic interaction and/or inclusion complexation between each enantiomer and chiral selector. In general, the chiral resolution of dansyl amino acids was enhanced at higher pH, which indicates that the carboxylate group on the analytes may interact with the imidazolium group of cationic cyclodextrin. For most analytes, a distinct maximum in enantioresolution was obtained at pH 8.0. Moreover, the chiral separation can be further improved by careful tuning of the separation parameters such as higher selector concentration (e.g. 10 mM), lower temperature, and addition of methanol. Enantioseparation of a standard mixture of these dansyl amino acids was further achieved in a single run within 30 min.

  14. Effects of prone and supine position on oxygenation and inflammatory mediator in a hydrochloric acid-induced lung dysfunction in rats Efeitos da posição prona e supina na oxigenação e mediador inflamatório na disfunção pulmonar induzida por ácido clorídrico em ratos

    Directory of Open Access Journals (Sweden)

    Wagner Rogério Souza de Oliveira

    2008-10-01

    Full Text Available PURPOSE: To compare the effectiveness of mechanical ventilation of supine versus prone position in hydrochloric acid (HCl-induced lung dysfunction. METHODS: Twenty, adult, male, Wistar-EPM-1 rats were anesthetized and randomly grouped (n=5 animals per group as follows: CS-MV (mechanical ventilation in supine position; CP-MV (mechanical ventilation in prone position; bilateral instillation of HCl and mechanical ventilation in supine position (HCl+S; and bilateral instillation of HCl and mechanical ventilation in prone position (HCl+P. All groups were ventilated for 180 minutes. The blood partial pressures of oxygen and carbon dioxide were measured in the time points 0 (zero; 10 minutes before lung injury for stabilization, and at the end of times acid injury, 60, 120 and 180 minutes of mechanical ventilation. At the end of experiment the animals were euthanized, and bronchoalveolar lavages (BALs were taken to determine the contents of total proteins, inflammatory mediators, and lungs wet-to-dry ratios. RESULTS: In the HCl+P group the partial pressure of oxygen increased when compared with HCl+S (128.0±2.9 mmHg and 111.0±6.7 mmHg, respectively within 60 minutes. TNF-α levels in BAL do not differ significantly in the HCl+P group (516.0±5.9 pg/mL, and the HCl+S (513.0±10.6 pg/mL. CONCLUSION: The use of prone position improved oxygenation, but did not reduce TNF-α in BAL upon lung dysfunction induced by HCl.OBJETIVO: Comparar os efeitos da ventilação mecânica em posição prona versus supina na disfunção pulmonar induzida por ácido clorídrico (HCl. MÉTODOS: Vinte ratos, adultos, Wistar-EPM-1 foram anestesiados e distribuídos aleatoriamente em grupos (n=5 animais por grupo: CS-MV (controle, ventilado mecanicamente em posição supina; CP-MV (controle, ventilado mecanicamente em posição prona; instilação bilateral de HCl e ventilação mecânica em posição supina (HCl+S ou ventilação em posição prona (HCl+P. Todos os grupos

  15. SEPARATION OF SATURED AND UNSATURATED FATTY ACIDS FROM PALM FATTY ACIDS DISTILLATES IN CONTINUOUS MULTISTAGE COUNTERCURRENT COLUMNS WITH SUPERCRITICAL CARBON DIOXIDE AS SOLVENT: A PROCESS DESIGN METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Nélio Teixeira MACHADO

    1997-12-01

    Full Text Available In this work the separation of multicomponent mixtures in counter-current columns with supercritical carbon dioxide has been investigated using a process design methodology. First the separation task must be defined, then phase equilibria experiments are carried out, and the data obtained are correlated with thermodynamic models or empirical functions. Mutual solubilities, Ki-values, and separation factors aij are determined. Based on this data possible operating conditions for further extraction experiments can be determined. Separation analysis using graphical methods are performed to optimize the process parameters. Hydrodynamic experiments are carried out to determine the flow capacity diagram. Extraction experiments in laboratory scale are planned and carried out in order to determine HETP values, to validate the simulation results, and to provide new materials for additional phase equilibria experiments, needed to determine the dependence of separation factors on concetration. Numerical simulation of the separation process and auxiliary systems is carried out to optimize the number of stages, solvent-to-feed ratio, product purity, yield, and energy consumption. Scale-up and cost analysis close the process design. The separation of palmitic acid and (oleic+linoleic acids from PFAD-Palm Fatty Acids Distillates was used as a case study.

  16. Hot test of a TALSPEAK procedure for separation of actinides and lanthanides using recirculating DTPA-lactic acid solution

    International Nuclear Information System (INIS)

    Persson, G.; Svantesson, I.; Wingefors, S.; Liljenzin, J.O.

    1984-01-01

    Results are reported from a hot test of a TALSPEAK type process for separation of higher actinides (Am, Cm) from lanthanides. Actinides and lanthanides are extracted by 1 M HDEHP and separated by selective strip of the actinides, using a mixture of DTPA and lactic acid (reversed TALSPEAK process). In order to minimize the generation of secondary waste, a procedure using recirculating DTPA-Lactic acid solution has been developed. A separation factor between Am and Eu of 132 was achieved. In regard to separations of Am and Cm from commercial HLLW (high level liquid wastes), the factor corresponds to 1.5% of the lanthanide group remaining with the actinides. The loss of Am was about 0.2%. 9 figures, 3 tables

  17. Towards multimodal HPLC separations on humic acid-bonded aminopropyl silica: RPLC and HILIC behavior.

    Science.gov (United States)

    Gezici, Orhan; Kara, Hüseyin

    2011-09-15

    The stationary phase characteristics of the material obtained through immobilization of humic acid (HA) to aminopropyl silica (APS) via amide-bond formation were investigated. The material was characterized in terms of elemental analysis, FTIR, thermogravimetric analyses, pH point of zero charge measurements, potentiometric titrations, and contact angle measurements. Amount of HA bonded to APS was determined from the elemental analysis results, and found as 170 mgHA/gAPS. Stability of the material was studied in aqueous media at different pH values, and amount of HA released at pH=8 did not exceed 2% of the total immobilized HA. Stationary phase characteristics of the well-characterized material were investigated in an HPLC system by using some low-molecular weight polar compounds (i.e. some nucleosides and nucleobases) as test solutes. Effect of some experimental variables such as column conditioning, composition of mobile phase, and temperature on the chromatographic behavior of the studied compounds was studied. Role of ammonium solutions at different pH values on retentive properties of the species was also studied. Retention factors (k') versus volume percentage of organic modifier exhibited a U-curve, which was evaluated as an indication for RPLC/HILIC mixed-mode behavior of the stationary phase. Orthogonality between RPLC and HILIC modes was analyzed through geometric approach, and found as 48.5%. Base-line separation for the studied groups of compounds was achieved under each studied mode, and some differentiations were observed in elution order of the compounds depending on the HPLC mode applied. Chromatograms recorded under RPLC and HILIC modes were compared with those recorded on APS under similar conditions, and thus the influence/importance of HA immobilization process was evaluated in detail. In light of the obtained results, immobilized HA is represented as a useful stationary phase for HPLC separations. Copyright © 2011 Elsevier B.V. All rights

  18. Chromatographic separation of rhenium in alumina-methanol/sulfuric acid system

    International Nuclear Information System (INIS)

    Oguma, Koichi

    1983-01-01

    The adsorption behavior of a number of metals on alumina was surveyed in a methanol-(0.005 -- 0.5) M H 2 SO 4 (3 : 1 v/v) developing solvent by thin-layer chromatography. Over the acid concentration range tested, Re(VII) does not favor the alumina phase to any great extent while the most other metals are strongly adsorbed on alumina. These findings allowed to establish a column chromatographic technique for selective separation of rhenium in a methanol-0.05 M H 2 SO 4 (3 : 1 v/v) eluent. The separation technique thus established was applied to molybdenite analysis for rhenium. About 100-mg powdered sample containing ca. 100 ppm rhenium was decomposed with HNO 3 and then evaporated nearly to dryness. The residue was dissolved in NH 4 OH and the excess NH 4 OH was expelled by evaporation to dryness. The residue was dissolved in 2.5-ml 0.5 M H 2 SO 4 and 10-ml water, the insoluble materials filtered off, and the filtrate diluted to exactly 25 ml with water. A 10-ml aliquot of this solution was mixed with 30-ml methanol and the mixture was passed through a column (diameter 15 mm, bed height 30 mm) containing 5 g of alumina. The column was then washed with 20 ml of a methanol-0.05 M H 2 SO 4 (3 : 1 v/v) mixture. Rhenium was recovered from the loaded solution and the subsequent washings, and was determined spectrophotometrically with Methylene Blue as a chromogenic reagent. The values obtained from four samples of molybdenite are in good agreement with those obtained by neutron activation analysis. The relative standard deviation (n = 4; calculated from the range) was between 2.0 and 5.2 %. (author)

  19. Separating NaCl and AlCl3·6H2O Crystals from Acidic Solution Assisted by the Non-Equilibrium Phase Diagram of AlCl3-NaCl-H2O(-HCl Salt-Water System at 353.15 K

    Directory of Open Access Journals (Sweden)

    Huaigang Cheng

    2017-08-01

    Full Text Available Extracting AlCl3·6H2O from acid leaching solution through crystallization is one of the key processes to extracting aluminum from fly ash, coal gangue and other industrial solid wastes. However, the obtained products usually have low purity and a key problem is the lack of accurate data for phase equilibrium. This paper presented the non-equilibrium phase diagrams of AlCl3-NaCl-H2O (HCl salt-water systems under continuous heating and evaporation conditions, which were the main components of the acid leaching solution obtained through a sodium-assisted activation hydrochloric acid leaching process. The ternary system was of a simple eutonic type under different acidities. There were three crystalline regions; the crystalline regions of AlCl3·6H2O, NaCl and the mixture AlCl3·6H2O/NaCl, respectively. The phase diagram was used to optimize the crystallization process of AlCl3·6H2O and NaCl. A process was designed to evaporate and remove NaCl at the first stage of the evaporation process, and then continue to evaporate and crystallize AlCl3·6H2O after solid-liquid separation. The purities of the final salt products were 99.12% for NaCl and up to 97.35% for AlCl3·6H2O, respectively.

  20. Anion exchange separation of the light lanthanoids with nitric acid-methyl alcohol mixed media at elevated temperature

    International Nuclear Information System (INIS)

    Usuda, S.; Magara, M.

    1987-01-01

    Anion exchange chromatography with nitric acid-methyl alcohol mixed media at elevated temperature was applied to mutual separation of the light lanthanoids, La, Ce, Pr, Nd and Pm. The individual elements could be effectively separated from each other, main fission products and actinoids with 0.01M HNO 3 -90% CH 3 OH or 0.5M HNO 3 -80% CH 3 OH eluent at 90 deg C. (author) 14 refs.; 3 tables

  1. Polyvinyl-alcohol-based magnetic beads for rapid and efficient separation of specific or unspecific nucleic acid sequences

    International Nuclear Information System (INIS)

    Oster, J.; Parker, Jeffrey; Brassard, Lothar

    2001-01-01

    The versatile application of polyvinyl-alcohol-based magnetic M-PVA beads is demonstrated in the separation of genomic DNA, sequence specific nucleic acid purification, and binding of bacteria for subsequent DNA extraction and detection. It is shown that nucleic acids can be obtained in high yield and purity using M-PVA beads, making sample preparation efficient, fast and highly adaptable for automation processes

  2. Separation of Molybdenum from Acidic High-Phosphorus Tungsten Solution by Solvent Extraction

    Science.gov (United States)

    Li, Yongli; Zhao, Zhongwei

    2017-10-01

    A solvent-extraction process for deep separation of molybdenum from an acidic high-phosphate tungsten solution was developed using tributyl phosphate (TBP) as the extractant and hydrogen peroxide (H2O2) as a complexing agent. The common aqueous complexes of tungsten and molybdenum (PMoxW12-xO40 3-, x = 0-12) are depolymerized to {PO4[Mo(O)2(O-O)]4}3- and {PO4[W(O)2(O-O)]4}3- by H2O2. The former can be preferentially extracted by TBP. The extractant concentration, phase contact time, H2O2 dosage, and H2SO4 concentration were optimized. By employing 80% by volume TBP, O:A = 1:1, 1.0 mol/L H2SO4, 1.0 mol/L H3PO4, a contact time of 2 min, and a molar ratio of H2O2/(W + Mo) equal to 1.5, 60.2% molybdenum was extracted in a single stage, while limiting tungsten co-extraction to 3.2%. An extraction isotherm indicated that the raffinate could be reduced to <0.1 g/L Mo in six stages of continuous counter-current extraction.

  3. Separation of trivalent actinide from lanthanide by a solvent extraction technique using imidazoledithiocarboxylic acid

    International Nuclear Information System (INIS)

    Miyashita, S.; Yanaga, M.; Okuno, K.; Suganuma, H.; Satoh, I.

    2006-01-01

    The extraction behavior of 241 Am and 152,154 Eu by a solvent extraction technique using imidazoledithiocarboxylic acid (IMD) were investigated. Although the solubility of IMD into organic solvent is very poor, it was improved by the formation of ion pair with hydrophobic cation, such as tetrabutylammonium ion (TBA + ) or tetraoctylammonium ion (TOA + ). The obtained tetrabutylammonium imidazole-dithiocarboxylate (TBA + IMD - ) and tetraoctylammonium imidazoledithiocarboxylate (TOA + TMD - ) are able to solve into various organic solvents, for example cyclohexanone, chloroform and nitrobenzene, but not to solve into nonpolar alkane. The radionuclides of Am(III) and Eu(III) are able to be extracted in the region of 2 eq + IMD - /cyclohexanone and TOA + IMD - /cyclohexanone. The distribution ratio of Am(III) is higher than that of Eu(III) when the organic phase is 0.1 M TBA + IMD - /cyclohexanone and the aqueous phase is 1.0 M (H,Na)NO 3 . The separation factor (Am(III)/Eu(III)) at pH eq =5.5 is ca. 30. In the region of pH>6, the distribution ratios of Am(III) and Eu(III) in the system described above showed constant values, respectively. (author)

  4. Advanced Acid Gas Separation Technology for the Utilization of Low Rank Coals

    Energy Technology Data Exchange (ETDEWEB)

    Kloosterman, Jeff

    2012-12-31

    Air Products has developed a potentially ground-breaking technology – Sour Pressure Swing Adsorption (PSA) – to replace the solvent-based acid gas removal (AGR) systems currently employed to separate sulfur containing species, along with CO{sub 2} and other impurities, from gasifier syngas streams. The Sour PSA technology is based on adsorption processes that utilize pressure swing or temperature swing regeneration methods. Sour PSA technology has already been shown with higher rank coals to provide a significant reduction in the cost of CO{sub 2} capture for power generation, which should translate to a reduction in cost of electricity (COE), compared to baseline CO{sub 2} capture plant design. The objective of this project is to test the performance and capability of the adsorbents in handling tar and other impurities using a gaseous mixture generated from the gasification of lower rank, lignite coal. The results of this testing are used to generate a high-level pilot process design, and to prepare a techno-economic assessment evaluating the applicability of the technology to plants utilizing these coals.

  5. Simultaneous separation and detection of actinides in acidic solutions using an extractive scintillating resin.

    Science.gov (United States)

    Roane, J E; DeVol, T A

    2002-11-01

    An extractive scintillating resin was evaluated for the simultaneous separation and detection of actinides in acidic solutions. The transuranic extractive scintillating (TRU-ES) resin is composed of an inert macroporous polystyrene core impregnated with organic fluors (diphenyloxazole and 1,4-bis-(4-methyl-5-phenyl-2-oxazolyl)benzene) and an extractant (octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide in tributyl phosphate). The TRU-ES resin was packed into FEP Teflon tubing to produce a flow cell (0.2-mL free column volume), which is placed into a scintillation detection system to obtain pulse height spectra and time series data during loading and elution of actinides onto/from the resin. The alpha-particle absolute detection efficiencies ranged from 77% to 96.5%, depending on the alpha energy and quench. In addition to the on-line analyses, off-line analyses of the effluent can be conducted using conventional detection methods. The TRU-ES resin was applied to the quantification of a mixed radionuclide solution and two actual waste samples. The on-line characterization of the mixed radionuclide solution was within 10% of the reported activities whereas the agreement with the waste samples was not as good due to sorption onto the sample container walls and the oxidation state of plutonium. Agreement between the on-line and off-line analyses was within 35% of one another for both waste samples.

  6. Separation of actinides and lanthanides from acidic nuclear wastes by supported liquid membranes

    International Nuclear Information System (INIS)

    Danesi, P.R.; Chiarizia, R.; Rickert, P.; Horwitz, E.P.

    1985-01-01

    Supported liquid membranes, SLM, consisting of a solution of 0.25 M octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) and 0.75 M tributylphosphate (TBP) in decalin absorbed on thin microporous polypropylene supports, have been studied for their ability to perform selective separations and concentrations of actinide and lanthanide ions from synthetic acidic nuclear wastes. The permeability coefficients of selected actinides (Am, Pu, U, Np) and of some of the other major components of the wastes have been measured using SLMs in flat-sheet and hollow-fiber configurations. The results have shown that with the thin (25 μm) flat-sheet SLMs, using Celgard 2500 as support, the membrane permeation process is mainly controlled by the rate of diffusion through the aqueous boundary layers. With the thicker (430 μm) hollow-fiber SLMs, using Accurel hollow-fibers as support, the membrane permeation process is controlled by the rate of diffusion through both the SLM and the aqueous boundary layers. Hollow-fibers SLMs exhibited lower permeability coefficients and longer life-times. The experiments have shown that the actinides can be very efficiently removed from the synthetic waste solutions to the point that the resulting solution could be considered a non-transuranic waste (less than 100 mCi/g of disposed form). The work has demonstrated that actinide removal from synthetic waste solutions is a feasible chemical process at the laboratory scale level

  7. Applications of electrochemically-modulated liquid chromatography (EMLC): Separations of aromatic amino acids and polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Li [Iowa State Univ., Ames, IA (United States)

    1998-03-27

    The research in this thesis explores the separation capabilities of a new technique termed electrochemically-modulated liquid chromatography (EMLC). The thesis begins with a general introduction section which provides a literature review of this technique as well as a brief background discussion of the two research projects in each of the next two chapters. The two papers which follow investigate the application of EMLC to the separation of a mixture of aromatic amino acids and of a mixture of polycyclic aromatic hydrocarbons (PAHs). The last section presents general conclusions and summarizes the thesis. References are compiled in the reference section of each chapter. The two papers have been removed for separate processing.

  8. Membrane fractionation of herring marinade for separation and recovery of fats, proteins, amino acids, salt, acetic acid and water

    DEFF Research Database (Denmark)

    Fjerbæk Søtoft, Lene; Lizarazu, Juncal Martin; Razi Parjikolaei, Behnaz

    2015-01-01

    In the production of marinated herring, nearly one ton of acidic saline marinade is produced per 1.5 tons herring fillet. This spent marinade contains highly valuable compounds such as proteins and amino acids. Membranes are suited to recover these substances. In this work, six membrane stages...... containing sugars, amino acids and smaller peptides and a NF permeate containing salt and acetic acid ready for reuse. 42% of the spent marinade is recovered to substitute fresh water and chemicals. The Waste water amount is reduced 62.5%. Proteins are concentrated 30 times, while amino acids and smaller...

  9. Cryochromatography: a method for the separation of phosphoglycerides according to the number and length of saturated fatty acid components

    International Nuclear Information System (INIS)

    Henderson, R.F.; Clayton, M.H.

    1974-01-01

    A thin layer chromatographic method utilizing ultracold temperatures has been developed to separate phosphoglycerides containing only long-chain saturated fatty acids from phosphoglycerides containing fatty acids with any degree of unsaturation. The method is direct, nondiluting, and nondestructive. Since the surfactant lipids found in lung contain only long-chain, saturated fatty acids, the method should be particularly useful to those in lung lipid research. Studies on the uptake of labeled precursors into the lung surfactant lipids as well as work on quantitation of surfactant lecithins in the lung can be facilitated by this method. (U.S.)

  10. Method to separate lignin-rich solid phase from acidic biomass suspension at an acidic pH

    Science.gov (United States)

    Yasarla, Kumar Lakshmi Rakesh; Ramarao, Bandaru V; Amidon, Thomas

    2017-09-05

    A method of separating a lignin-rich solid phase from a solution suspension, by pretreating a lignocellulosic biomass with a pretreatment fluid having remove soluble components, colloidal material and primarily lignin containing particles; separating the pretreated lignocellulosic biomass from the pretreatment fluid with soluble components, colloidal material and primarily lignin containing particles; flocculating the separated pretreatment fluid with soluble components, colloidal material and primarily lignin containing particles using polyethylene oxide (i.e., PEO) or cationic Poly acrylamide (i.e., CPAM) as a flocculating agent; and filtering the flocculated separated pretreatment fluid with soluble components, colloidal material and primarily lignin containing particles to remove agglomerates.

  11. Separation and determination of the enantiomers of lactic acid and 2-hydroxyglutaric acid by chiral derivatization combined with GC-MS.

    Science.gov (United States)

    Ding, Xuemei; Lin, Shuhai; Weng, Hongbo; Liang, Jianying

    2018-03-30

    Lactic acid and 2-hydroxyglutaric acid are chiral metabolites that have two distinct d and l enantiomers with distinct biochemical properties. Perturbations of single enantiomeric form have been found to be closely related to certain diseases. The ability to differentiate the d and l enantiomers is therefore important for these disease studies. Herein, we describe a method for the separation and determination of lactic acid and 2-hydroxyglutaric acid enantiomers by chiral derivatization (with l-menthol and acetyl chloride) combined with gas chromatography and mass spectrometry. The two pairs of enantiomers mentioned above exhibited linear calibration curves with correlation coefficient (R 2 ) exceeding 0.99. The measured data were accurate in the acceptable recovery range of 88.17-102.30% with inter-day and intra-day precisions (relative standard deviations) in the 4.23-17.26% range. The limits of detection for d- lactic acid, l-lactic acid, d-2-hydroxyglutaric acid and l-2-hydroxyglutaric acid were 0.13, 0.11, 1.12 and 1.16 μM, respectively. This method was successfully applied to analyze mouse plasma. The d-lactic acid levels in type 2 diabetes mellitus mouse plasma were observed to be significantly higher (P lactic acid may serve as an indicator for type 2 diabetes mellitus. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  12. Separation Mechanism of Fatty Acids from Waste Cooking Oil and Its Flotation Performance in Iron Ore Desiliconization

    Directory of Open Access Journals (Sweden)

    Wenda Guo

    2017-12-01

    Full Text Available Using the mixed fatty acids (MFA produced by waste cooking oil as flotation collectors directly, the flotation effect is usually not satisfactory, especially at lower temperature, which may be due to the presence of large amounts of saturated fatty acids. In this study, waste cooking oil was separated into saturated fatty acids (SFA and unsaturated fatty acids (UFA. The separation mechanism was studied by molecular simulation based on quantum and molecular mechanics. SFA and UFA were analyzed by iodine value, melting point measurement and Fourier transform infrared (FT-IR spectroscopy to check the result of the separation. The micro-flotation and bench-scale flotation tests were performed to investigate the flotation differences between SFA and UFA. The results showed that the poor flotation performance of waste cooking oil was due to the large amount of SFA in presence. If the SFA was separated out, the TFe grade and recovery of the flotation concentrates would be increased by 4.09 and 2.70 percentage points, respectively and the SiO2 grade would be 4.03 percentage points lower at the same time. This study would provide technical supports and theoretical guidance for the waste cooking oil application in the field of mineral processing.

  13. Feasibility of isotachochromatography as a method for the preparative separation of weak acids and weak bases. II. Experimental verification

    NARCIS (Netherlands)

    Kooistra, C.; Sluyterman, L.A.A.E.

    1988-01-01

    The theory of isotachochromatography has been verified and proved to be essentially correct. Acetate was used as a leading buffer and mostly serine as a terminal buffer to separate acids with pKa values intermediate between those of the leading and terminal buffers on a column of Dowex 50W-X2.

  14. Fluorescent boronic acid terminated polymer grafted silica particles synthesized via click chemistry for affinity separation of saccharides

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zhifeng, E-mail: 897061147@qq.com; Deng, Peihong; Tang, Siping; Li, Junhua

    2014-07-01

    Boronic acids are important for effective separation of biological active cis-diols. For the purpose of constructing a new type of saccharide-sensitive material which can not only provide convenient separation but also improve the access of boronic acid to guest molecules, the fluorogenic boronic acid terminated, thermo-sensitive polymers (BA-polyNIPAm) were grafted to an alkyne modified silica gel through the exploitation of click chemistry. The BA-polyNIPAm grafted silica gel (BA-polyNIPAm-SG) was characterized by FT-IR, fluorescence spectra, fluorescence microscopy, elemental analysis (EA), thermal gravimetric analysis (TGA), scanning electron microscope (SEM) and so on. BA-polyNIPAm-SG displayed affinity binding ability for saccharides under physiological pH value and allowed saccharides to be conveniently separated from solution. The maximum binding capacities for fructose and glucose are 83.2 μmol/g and 70.4 μmol/g polymer, respectively. The intensity of fluorescence emission of BA-polyNIPAm-SG increased with the increasing of fructose concentration. The present study provides a new kind of composite material which contains moveable and flexible grippers for recognizing and binding guest molecules. - Highlights: • Fluorogenic boronic acid terminated polymers were conjugated to silica particle. • The prepared material can conveniently separate saccharides from solution. • The prepared material displays increased fluorescence emission upon binding fructose.

  15. Fluorescent boronic acid terminated polymer grafted silica particles synthesized via click chemistry for affinity separation of saccharides

    International Nuclear Information System (INIS)

    Xu, Zhifeng; Deng, Peihong; Tang, Siping; Li, Junhua

    2014-01-01

    Boronic acids are important for effective separation of biological active cis-diols. For the purpose of constructing a new type of saccharide-sensitive material which can not only provide convenient separation but also improve the access of boronic acid to guest molecules, the fluorogenic boronic acid terminated, thermo-sensitive polymers (BA-polyNIPAm) were grafted to an alkyne modified silica gel through the exploitation of click chemistry. The BA-polyNIPAm grafted silica gel (BA-polyNIPAm-SG) was characterized by FT-IR, fluorescence spectra, fluorescence microscopy, elemental analysis (EA), thermal gravimetric analysis (TGA), scanning electron microscope (SEM) and so on. BA-polyNIPAm-SG displayed affinity binding ability for saccharides under physiological pH value and allowed saccharides to be conveniently separated from solution. The maximum binding capacities for fructose and glucose are 83.2 μmol/g and 70.4 μmol/g polymer, respectively. The intensity of fluorescence emission of BA-polyNIPAm-SG increased with the increasing of fructose concentration. The present study provides a new kind of composite material which contains moveable and flexible grippers for recognizing and binding guest molecules. - Highlights: • Fluorogenic boronic acid terminated polymers were conjugated to silica particle. • The prepared material can conveniently separate saccharides from solution. • The prepared material displays increased fluorescence emission upon binding fructose

  16. Formation of iron oxides from acid mine drainage and magnetic separation of the heavy metals adsorbed iron oxides

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Hee Won; Kim, Jeong Jin; Kim, Young Hun [Andong National University, Andong (Korea, Republic of); Ha, Dong Woo [Korea Electrotechnology Research Institute, Changwon (Korea, Republic of)

    2016-03-15

    There are a few thousand abandoned metal mines in South Korea. The abandoned mines cause several environmental problems including releasing acid mine drainage (AMD), which contain a very high acidity and heavy metal ions such as Fe, Cu, Cd, Pb, and As. Iron oxides can be formed from the AMD by increasing the solution pH and inducing precipitation. Current study focused on the formation of iron oxide in an AMD and used the oxide for adsorption of heavy metals. The heavy metal adsorbed iron oxide was separated with a superconducting magnet. The duration of iron oxide formation affected on the type of mineral and the degree of magnetization. The removal rate of heavy metal by the adsorption process with the formed iron oxide was highly dependent on the type of iron oxide and the solution pH. A high gradient magnetic separation (HGMS) system successfully separated the iron oxide and harmful heavy metals.

  17. Studies on entrained DNPPA separation by charcoal adsorption from aqueous solutions generated during uranium recovery from strong phosphoric acid

    International Nuclear Information System (INIS)

    Singh, D.K.; Vijayalakshmi, R.; Singh, H.

    2010-01-01

    During the separation of metal ions by solvent extraction technique in hydrometallurgical operations, organic solvents either get entrained or dissolved in various types of aqueous streams, which need to be separated out to prevent environmental pollution and solvent loss. Generally entrained solvents are separated on plant scale by parallel plate separators or by froth floatation cells, while the dissolved solvents are recovered either by organic diluent wash or by charcoal adsorption. A novel process has been developed to recover uranium from merchant grade phosphoric acid (MGA) employing synergistic mixture of DNPPA (di-nonyl phenyl phosphoric acid ) and TOPO (tri-n-octyl phosphine oxide) dissolved in petrofin. After recovery of uranium, MGA has to be returned to the host company for the production of fertilizer. This MGA has to be free from any contamination due to DNPPA and TOPO. Separation of DNPPA and TOPO from MGA by diluent wash method has been reported. There is no information available in literature for the separation of DNPPA and TOPO from such aqueous streams by carbon adsorption. The present investigation describes the methodology based on charcoal adsorption study (batch and continuous column operation) to separate DNPPA from MGA. Three different types of charcoal namely coconut shell based, coal based and pelletized charcoal were evaluated for DNPPA separation from MGA containing 100 mg/L DNPPA. It was found that the % DNPPA adsorptions in single contact (0.5g C/50 ml) were 57, 34 and 10 in coconut shell, coal based and pelletised charcoal respectively. Based on the results, the coconut shell based charcoal was selected for further study. Adsorption of DNPPA by coconut shell based charcoal was investigated by carrying out the experiments with 50 ml MGA containing 770 mg/L DNPPA by adding 1 to 7 g charcoal respectively in separate beakers

  18. Quantitative radio-chemical separation of calcium, strontium and barium

    International Nuclear Information System (INIS)

    Dupuis, M.C.; Dupuis, M.; Le Nagard, M.; Michot, H.

    1965-01-01

    A method for separation of Ca 45 , Sr 89 and Ba 140 has been developed for the radiochemical determination of these isotopes in a solution of fission with a large concentration of mineral salts. After removal of most fission products by solvent extraction (TTA-MIBK) at different pH, the alkaline earths are extracted from the aqueous phase at pH 9. After recovery with diluted hydrochloric acid, the three elements are adsorbed on cationic resin Dowex 50 and eluted sequentially with ammonium α - Hydroxy iso-butyrate using gradient concentration and pH. Ca 45 and Sr 89 are measured by β - counting and Ba 140 by γ spectrometry. The chemical yield approximates 80 per cent for calcium, and 70 per cent for strontium and barium. The decontamination factor is 10 5 for most fission products. Four separations can be performed in twenty hours. (authors) [fr

  19. Radiochemical studies in chemical separation and spectrographic determination of rare earths in thorium oxide matrix (Preprint No. RA.06)

    International Nuclear Information System (INIS)

    Adya, V.C.; Dhawale, B.A.; Rajeshwari, B.; Bangia, T.R.; Sastry, M.D.

    1989-01-01

    A chemical separation procedure was standardised for the separation of traces of rare earths from ThO 2 matrix using HDEHP (Di 2-ethyl hexyl phosphoric acid). The studies were carried out using both nitric acid and hydrochloric acid medium in different concentrations. The extraction studies were also carried out using radioactive isotopes of rare earths viz. 141 Ce, 152-154 Eu, 153 Gd, 170 Tm etc. The extraction was effective in both media. In 0.1 M HDEHP/xylene and 3 M HNO 3 , Ce was partially extracted into organic phase. So HCl/xylene medium was chosen for extraction purposes. The recovery was confirmed by both gamma counting and emission spectropgraphic method. It was found to be quantitative within experimental error. The separation procedure development here was used for determination of rare earths in thorium oxide matrix by emission spectrographic method. (author)

  20. Experimental and Model Studies on Continuous Separation of 2-Phenylpropionic Acid Enantiomers by Enantioselective Liquid-Liquid Extraction in Centrifugal Contactor Separators.

    Science.gov (United States)

    Feng, Xiaofeng; Tang, Kewen; Zhang, Pangliang; Yin, Shuangfeng

    2016-03-01

    Multistage enantioselective liquid-liquid extraction (ELLE) of 2-phenylpropionic acid (2-PPA) enantiomers using hydroxypropyl-β-cyclodextrin (HP-β-CD) as extractant was studied experimentally in a counter-current cascade of centrifugal contactor separators (CCSs). Performance of the process was evaluated by purity (enantiomeric excess, ee) and yield (Y). A multistage equilibrium model was established on the basis of single-stage model for chiral extraction of 2-PPA enantiomers and the law of mass conservation. A series of experiments on the extract phase/washing phase ratio (W/O ratio), extractant concentration, the pH value of aqueous phase, and the number of stages was conducted to verify the multistage equilibrium model. It was found that model predictions were in good agreement with the experimental results. The model was applied to predict and optimize the symmetrical separation of 2-PPA enantiomers. The optimal conditions for symmetric separation involves a W/O ratio of 0.6, pH of 2.5, and HP-β-CD concentration of 0.1 mol L(-1) at a temperature of 278 K, where eeeq (equal enantiomeric excess) can reach up to 37% and Yeq (equal yield) to 69%. By simulation and optimization, the minimum number of stages was evaluated at 98 and 106 for eeeq > 95% and eeeq > 97%. © 2016 Wiley Periodicals, Inc.

  1. Selected nutrient contents, fatty acid composition, including conjugated linoleic acid, and retention values in separable lean from lamb rib loins as affected by external fat and cooking method.

    Science.gov (United States)

    Badiani, Anna; Montellato, Lara; Bochicchio, Davide; Anfossi, Paola; Zanardi, Emanuela; Maranesi, Magda

    2004-08-11

    Proximate composition and fatty acid profile, conjugated linoleic acid (CLA) isomers included, were determined in separable lean of raw and cooked lamb rib loins. The cooking methods compared, which were also investigated for cooking yields and true nutrient retention values, were dry heating of fat-on cuts and moist heating of fat-off cuts; the latter method was tested as a sort of dietetic approach against the more traditional former type. With significantly (P cooking losses, dry heating of fat-on rib-loins produced slightly (although only rarely significantly) higher retention values for all of the nutrients considered, including CLA isomers. On the basis of the retention values obtained, both techniques led to a minimum migration of lipids into the separable lean, which was higher (P cooking of the class of CLA isomers (including that of the nutritionally most important isomer cis-9,trans-11) was more similar to that of the monounsaturated than the polyunsaturated fatty acids.

  2. Equilibrium and non-equilibrium extraction separation of rare earth metals in presence of diethylenetriaminepentaacetic acid in aqueous phase

    International Nuclear Information System (INIS)

    Azis, Abdul; Teramoto, Masaaki; Matsuyama, Hideto.

    1995-01-01

    Equilibrium and non-equilibrium extraction separations of rare earth metals were carried out in the presence of chelating agent in the aqueous phase. The separation systems of the rare earth metal mixtures used were Y/Dy, Y/Ho, Y/Er and Y/Tm, and the chelating agent and the extractant were diethylenetriaminepentaacetic acid (DTPA) and bis (2,4,4-trimethylpentyl) phosphinic acid (CYANEXR 272), respectively. For Y/Dy and Y/Ho systems, higher selectivities were obtained in equilibrium separation compared with those in non-equilibrium separation. On the other hand, the selectivities in non-equilibrium separation were higher for Y/Er and Y/Tm systems. In the separation condition suitable to each system, the addition of DTPA to the aqueous phase was found to be very effective for obtaining higher selectivities. The distribution ratios of the rare earth metals and the selectivities in the equilibrium separations obtained experimentally were thoroughly analyzed by considering various equilibria such as the extraction equilibrium and the complex formation equilibrium between rare earth metals and DTPA in the aqueous phase. Moreover, the extraction rates and the selectivities in the non-equilibrium separations were also analyzed by the extraction model considering the dissociation reactions of the rare earth metal-DTPA complexes in the aqueous stagnant layer. Based on these analyses, we presented an index which is useful for selecting the optimum operation mode. Using this index, we can predict that the selectivities under equilibrium conditions are higher than those under non-equilibrium conditions for Y/Dy and Y/Ho systems, while for Y/Er and Y/Tm systems, higher selectivities are obtained under non-equilibrium conditions. The experimental results were in agreement with predictions by this index. Further, the selectivities in various systems including other chelating agents and extractants were discussed based on this index. (J.P.N.)

  3. Chiral separation of α-cyclohexylmandelic acid enantiomers by high-speed counter-current chromatography with biphasic recognition

    Science.gov (United States)

    Tong, Shengqiang

    2010-01-01

    This work concentrates on a novel chiral separation technology named biphasic recognition applied to resolution of α-cyclohexylmandelic acid enantiomers by high-speed counter-current chromatography (HSCCC). The biphasic chiral recognition HSCCC was performed by adding lipophilic (−)-2-ethylhexyl tartrate in the organic stationary phase and hydrophilic hydroxypropyl-β-cyclodextrin in the aqueous mobile phase, which preferentially recognized the (−)-enantiomer and (+)-enantiomer, respectively. The two-phase solvent system composed of n-hexane-methyl tert-butyl ether-water (9:1:10, v/v/v) with the above chiral selectors was selected according to the partition coefficient and separation factor of the target enantiomers. Various parameters involved in the chiral separation were investigated, namely the types of the chiral selector (CS); the concentration of each chiral selector; pH of the mobile phase; and the separation temperature. The mechanism involved in this biphasic recognition chiral separation by HSCCC was discussed. Langmuirian isotherm was employed to estimate the loading limits for each chiral selector. The overall experimental results show that the HSCCC separation of enantiomer based on biphasic recognition is much more efficient than the traditional monophasic recognition chiral separation, since it utilizes the cooperation of both lipophilic and hydrophilic chiral selectors. PMID:20303497

  4. Application of Taguchi method for separation of uranium from acetate bearing wastewater using hydroxamic acid based sorbent

    International Nuclear Information System (INIS)

    Satpati, S.K.; Hareendran, K.; Roy, S.B.; Vaidya, A.; Bankar, V.; Dasgupta, K.; Pal, S.

    2016-01-01

    Separation and recovery of uranium from effluent of nuclear facility has drawn immense attention in separation science research. The acetic acid based uranium solution effluent generated in uranium metal powder production facility was targeted for the study. Solid state separation technique has been employed using hydroxamic acid based chelating sorbent because of several advantages. In the study, the sorbent performances have been evaluated for its important parameters like isotherm, efficiency and kinetics. The equilibrium adsorption capacity (q e ) and distribution coefficient (K d ) of U(VI) have been evaluated as 3.24 mg/g sorbent and 805 ml/g sorbent respectively. Uranium has been recovered using HCl solution. Uranium removal from the feed was found to be more than 95% and the recovery of uranium was more than 99% from the adsorbed phase. Elution process is faster than sorption process. Taguchi optimization method has been applied for designing experimental study and also to identify the optimum operational conditions for uranium separation process.The developed process is useful for separation and recovery of uranium from acetate bearing wastewater generated in uranium processing facilities

  5. Separation of zirconium and hafnium from acompanying elements by paper chromatography in the systems of alcohol-acid

    International Nuclear Information System (INIS)

    Lebedeva, G.G.; Viktorova, M.E.

    1980-01-01

    Solvents have been chosen and investigated which provide expressed separation of zirconium and hafnium at the analysis of mineral raw materials by paper chromatography. The systems with HNO 3 and HCl containing methyl, ethyl, propyl and butyl alcohols have been studied as mobile phases for separation of zirconium and hafnium. It has been shown that alcohol contents and solvent acidity affect the Rsub(f) value of these elements. The C 2 H 5 OH-5MHCl and C 2 H 5 OH-5MHNO 3 systems are most optimal for pre-concentration of zirconium and hafnium

  6. Separation of tungsten and rhenium on alumina

    Directory of Open Access Journals (Sweden)

    MILOVAN SM. STOILJKOVIC

    2004-09-01

    Full Text Available The conditions for the efficient separation of tungsten(VI and rhenium (VII on alumina were established. The distribution coefficients Kd for tungstate and perrhenate anions, as well as the separation factors a (a = KdWO42-/Kd ReO4- were determined using hydrochloric or nitric acid as the aqueous media. A solution of sodium chloride in the pH range 2–6 was also examined. Under all the tested experimental conditions, alumina is a much better adsorbent for tungsten than for rhenium. The obtained results indicated that the best separation of these two elements is achieved when 0.01– 0.1 mol dm-3 HCl or 1.0 mol dm-3 HNO3 are used as the aqueous media. If NaCl is used as the aqueous phase, the best separation is achieved with 0.20 mol dm-3 NaCl, pH 4–6. Under these experimental conditions, the breakthrough and saturation capacities of alumina for tungsten at pH 4 are 17 and 26 mg W/g Al2O3, respectively. With increasing pH, these values decrease. Thus, at pH 6 they are only 4 and 13 mg W/g Al2O3, respectively.

  7. Survey of knowledge of hazards of chemicals potentially associated with the advanced isotope separation processes

    International Nuclear Information System (INIS)

    Chester, R.O.; Kirkscey, K.A.; Randolph, M.L.

    1979-09-01

    Hazards of chemical potentially associated with the advanced isotope separation processes are estimated based on open literature references. The tentative quantity of each chemical associated with the processes and the toxicity of the chemical are used to estimate this hazard. The chemicals thus estimated to be the most potentially hazardous to health are fluorine, nitric acid, uranium metal, uranium hexafluoride, and uranium dust. The estimated next most hazardous chemicals are bromine, hydrobromic acid, hydrochloric acid, and hydrofluoric acid. For each of these chemicals and for a number of other process-associated chemicals the following information is presented: (1) any applicable standards, recommended standards and their basis; (2) a brief discussion to toxic effects including short exposure tolerance, atmospheric concentration immediately hazardous to life, evaluation of exposures, recommended control procedures, chemical properties, and a list of any toxicology reviews; and (3) recommendations for future research

  8. Survey of knowledge of hazards of chemicals potentially associated with the advanced isotope separation processes

    Energy Technology Data Exchange (ETDEWEB)

    Chester, R.O.; Kirkscey, K.A.; Randolph, M.L.

    1979-09-01

    Hazards of chemical potentially associated with the advanced isotope separation processes are estimated based on open literature references. The tentative quantity of each chemical associated with the processes and the toxicity of the chemical are used to estimate this hazard. The chemicals thus estimated to be the most potentially hazardous to health are fluorine, nitric acid, uranium metal, uranium hexafluoride, and uranium dust. The estimated next most hazardous chemicals are bromine, hydrobromic acid, hydrochloric acid, and hydrofluoric acid. For each of these chemicals and for a number of other process-associated chemicals the following information is presented: (1) any applicable standards, recommended standards and their basis; (2) a brief discussion to toxic effects including short exposure tolerance, atmospheric concentration immediately hazardous to life, evaluation of exposures, recommended control procedures, chemical properties, and a list of any toxicology reviews; and (3) recommendations for future research.

  9. Physical chemistry and engineering of membranes for fat - fatty acid separations

    NARCIS (Netherlands)

    Keurentjes, J.

    1991-01-01

    Fatty acids have to be removed from non-mineral oil for several purposes. In the refining of edible oils and fats they have to be removed as a contaminant. In the enzymatic hydrolysis of oils, a high content in fatty acids results in a reduced conversion rate. In order to maintain a

  10. Quantification of fatty acids as methyl esters and phospholipids in cheese samples after separation of triacylglycerides and phospholipids.

    Science.gov (United States)

    Hauff, Simone; Vetter, Walter

    2009-03-23

    Determination of the individual fatty acid composition of neutral- and phospholipids as well as the phospholipid content of dairy food and other foodstuffs are important tasks in life sciences. For these purposes, a method was developed for the separation of lipids (standards of triolein and diacylphosphatidylcholines as well as three cheese samples) by solid-phase extraction using a self-packed column filled with partly deactivated silica. Non-halogenated solvents were used for the elution of the lipid classes. Cyclohexane/ethyl acetate (1:1, v/v) served for the elution of neutral lipids, while polar lipids were eluted with three solvents (ethyl acetate/methanol, methanol, and methanol/water) into one fraction. The separated lipid fractions were transesterified and the individual fatty acids were quantified by using gas chromatography coupled to electron ionization mass spectrometry (GC/EI-MS) in the selected ion monitoring (SIM) mode. The recovery rate for standard phosphatidylcholines was approximately 90% and cross-contamination from neutral lipids was negligible. The method was applied to cheese samples. Quantitative amounts of individual fatty acids in the phospholipid fraction were camembert, cheese. Differences in the fatty acid pattern of neutral and polar lipids were detected. The quantity of the fatty acids determined in the phospholipid fraction was divided by the factor 0.7 in order to convert the fatty acid content into the phospholipid content of the cheese samples. This factor is based on the contribution of 16:0 to dipalmitoylphosphatidylcholine (DPPC). The resulting DPPC equivalents (DPPC(eq)) were found to be representative for the average contribution of fatty acids to all classes of phospholipids in dairy products. Using this approach, the phospholipid content of lipids from mozzarella, camembert, and goat cream cheese was 0.60%, 1.42% and 0.79%, respectively.

  11. INVESTIGATION OF THE PROCESS OF TARTARIC ACID SEPARATION ON AMBERLITE XAD2 IMPREGNATED WITH AMBERLITE LA-2

    Directory of Open Access Journals (Sweden)

    N. Marchitan

    2012-12-01

    Full Text Available This work describes an investigation of the process of reactive ion-exchange separation of tartaric acid from model systems with macroreticular resin AmberliteXAD2 impregnated with liquid ion-exchanger Amberlite LA-2 in batch equipment.The condition of Amberlite XAD2 impregnation process was investigated. Freudlichand Langmuir equations were verified and values of enthalpy, entropy and Gibbs energy were calculated. This article is an extended abstract of a communicationpresented at the Conference Ecological Chemistry 2012.

  12. Titrimetric determination of thiocyanate in solutions of the hafnium-zirconium separation process

    International Nuclear Information System (INIS)

    Vazquez, Cristina; Botbol, Moises; Hernandez, M.H.

    1980-01-01

    The control of the thiocyanate concentration is necessary during the process of separating hafnium from zirconium by the hexone-thiocyanate method. Said control is carried out by titrimetric determination of thiocyanate in aqueous and organic solutions containing hydrochloric acid and ammonium thiocyanate in presence or absence of zirconium and/or hafnium. The method consists in a redox volumetric analysis using a cerium (IV) salt as titrating agent, and ferroine as the final point indicator. Owing to the instability of thiocyanate in an acid medium it is necessary to know previously if the decomposition of solutions with different concentration of ammonium thiocyanate and hydrochloric acid may have an influence upon the analytic results or may even invalidate them. In order to obtain reliable results, it must be taken into account that the stability of the solutions depends on the thiocyanate concentration, the acidity and the time elapsed from the moment the sample is taken until the test is performed. The decomposition process can be slowed down by cooling the solutions. This method allows to control the plant and does not require any special equipment. (M.E.L) [es

  13. Separation of saccharides derivatized with 2-aminobenzoic acid by capillary electrophoresis and their structural consideration by nuclear magnetic resonance.

    Science.gov (United States)

    He, Liping; Sato, Kae; Abo, Mitsuru; Okubo, Akira; Yamazaki, Sunao

    2003-03-01

    Saccharides including mono- and disaccharides were quantitatively derivatized with 2-aminobenzoic acid (2-AA). These derivatives were then separated by capillary zone electrophoresis with UV detection using 50mM sodium phosphate buffer as the running electrolyte solution. In particular, the saccharide derivatives with the same molecular weight as 2-AA aldohexoses (mannose and glucose) and 2-AA aldopentoses (ribose and xylose) were well separated. The underlying reasons for separation were explored by studying their structural data using 1H and 13C NMR. It was found that the configurational difference between their hydroxyl group at C2 or C3 could cause the difference in Stokes' radii between their molecules and thus lead to different electrophoretic mobilities. The correlation between the electrophoretic behavior of these carbohydrate derivatives and their structures was studied utilizing the calculated molecular models of the 2-AA-labeled mannose, glucose, ribose, and xylose.

  14. Synergistic extraction and separation of yttrium from heavy rare earths using mixture of sec-octylphenoxy acetic acid and bis(2,4,4-trimethylpentyl)phosphinic acid

    International Nuclear Information System (INIS)

    Sun Xiaobo; Zhao Junmei; Meng Shulan; Li Deqian

    2005-01-01

    Synergistic extraction and separation of yttrium (Y) from heavy rare earths (HRE) in chloride medium using mixture of sec-octylphenoxy acetic acid (CA-12, HA) and bis(2,4,4-trimethylpentyl)phosphinic acid (Cyanex272, HL) in n-heptane has been investigated. The synergistic enhancement coefficients, R max , were obtained for Ho 3+ (5.12), Y 3+ (5.34), Er 3+ (7.04), Tm 3+ (7.50), Yb 3+ (13.12) and Lu 3+ (17.58). The separation factors (SF) between Y 3+ and HRE were obtained, and it was found that Er 3+ would form the new complex as ErH 6 A 4 L 5 in the mixture system. A cation exchange mechanism was proposed. The equilibrium constant, formation constant and thermodynamic parameters such as ΔG = -18.48 kJ/mol, ΔH = -1.36 kJ/mol and ΔS = 0.058 kJ/mol were determined. The CA-12 and Cyanex272 mixture system showed higher extraction efficiency, larger separation factors as well as excellent stripping behaviors. The application potential of the mixture system to separate Y from HRE has been discussed

  15. Quantification of fatty acids as methyl esters and phospholipids in cheese samples after separation of triacylglycerides and phospholipids

    International Nuclear Information System (INIS)

    Hauff, Simone; Vetter, Walter

    2009-01-01

    Determination of the individual fatty acid composition of neutral- and phospholipids as well as the phospholipid content of dairy food and other foodstuffs are important tasks in life sciences. For these purposes, a method was developed for the separation of lipids (standards of triolein and diacylphosphatidylcholines as well as three cheese samples) by solid-phase extraction using a self-packed column filled with partly deactivated silica. Non-halogenated solvents were used for the elution of the lipid classes. Cyclohexane/ethyl acetate (1:1, v/v) served for the elution of neutral lipids, while polar lipids were eluted with three solvents (ethyl acetate/methanol, methanol, and methanol/water) into one fraction. The separated lipid fractions were transesterified and the individual fatty acids were quantified by using gas chromatography coupled to electron ionization mass spectrometry (GC/EI-MS) in the selected ion monitoring (SIM) mode. The recovery rate for standard phosphatidylcholines was ∼90% and cross-contamination from neutral lipids was negligible. The method was applied to cheese samples. Quantitative amounts of individual fatty acids in the phospholipid fraction were eq ) were found to be representative for the average contribution of fatty acids to all classes of phospholipids in dairy products. Using this approach, the phospholipid content of lipids from mozzarella, camembert, and goat cream cheese was 0.60%, 1.42% and 0.79%, respectively

  16. Chiral separations of mandelic acid by HPLC using molecularly imprinted polymers

    OpenAIRE

    Hung, Chin-Yin; Huang, Han-Hung; Hwang, Ching-Chiang

    2005-01-01

    Styrene is used in a variety of chemical industries. Environmental and occupational exposures to styrene occur predominantly through inhalation. The major metabolite of styrene is present in two enantiomeric forms, chiral R- and S- hydroxy-1-phenyl-acetic acid (R-and S-mandelic acid, MA). Thus, the concentration of MA, particularly of its enantiomers, has been used in urine tests to determine whether workers have been exposed to styrene. This study describes a method of analyzing mandelic aci...

  17. Spectrophotometric determination of uranium by previous extraction chromatography separation in polimetalic mineral, phosphorites and technological licours

    International Nuclear Information System (INIS)

    Moreno Bermudez, J.; Cabrera Quevedo, C.; Alfonso Mendez, L.; Rodriguez Aguilera, M.

    1994-01-01

    The development of an analytical procedure for spectrophotometric determination of uranium in polimetalic mineral, phosphorites and technological licours is described. The method is based on the previous separation of interfering elements by extraction chromatography and on spectrophotometric determination of uranium (IV) with arsenazo III in concentrated hydrochloric acid. Tributyl phosphate impregnate on politetrafluoroethylene is used as stationary phase and 5.5 M nitric acid is used as movie phase. The influence of matrix-component elements was studies. The development procedure was applied to real samples, being the results compared with those obtained by other well established analytical methods like gamma-spectrometry, laser fluorimetric, spectrophotometry previous uranium separation by liquid liquid extraction and anion exchange. The reproducibility is evaluated and the detection limited has been established for each studied matrix. A procedure for correcting the thorium interference has been developed for samples with a Th/ 3U8O higher than 0.2

  18. Separation of 99Tc from irradiated molybdenum oxide by extraction with trioctilamine

    International Nuclear Information System (INIS)

    Carvalho, O.G. de.

    1979-01-01

    A separation method of sup( 99 m)Tc, from irradiated molybdenum oxide, by extraction with trioctilamino in 1,2 dichloroethane, 2% v/v is studied. Two preliminary studies are done: 1) Stablishment of the shaking time necessary to reach the equilibrium between the organic and the aqueous phase; 2) Choice of the concentration of solution of TOA in 1,2 dichloroethane to obtain the best separation conditions of sup( 99 m)Tc. After stablishing these two parameters, the study of extraction in solutions of hydrochloric nitric and sulfuric acids in different concentrations is done, followed by the study of the variation of extraction percentage of sup( 99 m)Tc in relation to the molybdenum oxide mass and the back-extraction of sup( 99 m)Tc to the aqueous phase with solutions of perchloric acid 1,0 and 0,1 N and ammonium hydroxide 1,0 N. (Author) [pt

  19. tRNA acceptor-stem and anticodon bases embed separate features of amino acid chemistry

    Science.gov (United States)

    Carter, Charles W.; Wolfenden, Richard

    2016-01-01

    abstract The universal genetic code is a translation table by which nucleic acid sequences can be interpreted as polypeptides with a wide range of biological functions. That information is used by aminoacyl-tRNA synthetases to translate the code. Moreover, amino acid properties dictate protein folding. We recently reported that digital correlation techniques could identify patterns in tRNA identity elements that govern recognition by synthetases. Our analysis, and the functionality of truncated synthetases that cannot recognize the tRNA anticodon, support the conclusion that the tRNA acceptor stem houses an independent code for the same 20 amino acids that likely functioned earlier in the emergence of genetics. The acceptor-stem code, related to amino acid size, is distinct from a code in the anticodon that is related to amino acid polarity. Details of the acceptor-stem code suggest that it was useful in preserving key properties of stereochemically-encoded peptides that had developed the capacity to interact catalytically with RNA. The quantitative embedding of the chemical properties of amino acids into tRNA bases has implications for the origins of molecular biology. PMID:26595350

  20. Separation and immobilization of Sr and Cs contained in acidic media by using inorganic ion-exchangers. Literature survey

    Energy Technology Data Exchange (ETDEWEB)

    Yamagishi, Isao [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-07-01

    The present study deals with the survey of inorganic ion-exchangers suitable for separation and immobilization of Sr and Cs contained in acidic high-level liquid waste. The stabilities of published waste forms and their preparation processes were evaluated from the standpoint of conversion of exchangers containing Sr and Cs into appropriate waste forms. The essential results are below. (1) For separation and immobilization of Cs, crystalline silicotitanate seems to be the most promising exchanger. Insoluble ferrocyanides and phosphates are not suitable for immobilization without additives. Mordenite is inexpensive and commercially available but it would dissolve in highly acidic media. (2) For selective separation of Sr, there is no promising exchanger up to now. It is necessary either to modify separation condition or to synthesize a novel exchanger. (3) Soluble salts, glasses and ceramics are proposed as a storage or disposal form of separated Sr and Cs. Ceramics sintered by hot-pressing are favorable waste forms of inorganic ion-exchangers but their leachabilities and thermal conductivities are largely influenced by qualities of products. Crystallinity of a sintered exchanger depends on its composition. Exchanges of low Cs contents are often converted into amorphous materials whose chemical stabilities depend on solubilities of components of exchangers. (4) A new exchanger to be synthesized is crystalline and selective toward Sr and Cs. One meq/g is enough for Sr and Cs capacities, which are restricted by thermal and transmutation effects. Composition of the exchanger should be selected from the point of a scenario of separation and disposal. The solubilities of SiO{sub 2}, TiO{sub 2}, ZrO{sub 2}, Nb{sub 2}O{sub 5} and Ta{sub 2}O{sub 5} are low in acidic media and those of Al{sub 2}O{sub 3}, TiO{sub 2} and ZrO{sub 2}, in disposal circumstances. (5) Future works are optimization of separation scheme including development of exchangers, simplification of

  1. Study of the isotopic exchange associated with ionic exchange for the radiochemical separation of 233-Th

    International Nuclear Information System (INIS)

    Sepulveda Munita, C.J.A.

    1983-01-01

    The isotopic ion exchange procedure is applied in order to establish an analytical method for the determination of thorium by means of the 233 Th activity, when the presence of interfering elements does not allow a direct non-destructive activation analysis. The separation is based on the retention of 233 Th by a thorium saturated resin, due to the isotopic exchange effect, and subsequent elution of the interfering radioisotopes with a solution of thorium in diluted hydrochloric acid. The interfering elements were those which either present a great affinity for the resin or emit gamma rays with energies close to that of 233 Th (86.6 KeV), when a NaI(Tl) detector is used to obtain the gama-ray spectra of the irradiated samples. The equilibrium time for the thorium isotopic ion exchange and the distribution coefficients for the interfering elements were determined by using Bio-Rad AG 50W resins (100-200 mesh), with 4% to 8% of divinylbenzene. The best separation conditions were established in terms of the thorium and hydrochloric acid concentrations in the solution, the resin cross-linking degree, and the solution flow through the resin. The analytical method was applied to the determination of thorium in samples of ammonium diuranate as well in standard rock samples from the United States Geological Survey. The sensitivity, precision and accuracy of the method are also discussed. (Author) [pt

  2. DTDGA impregnated XAD-16 beads for separation and recovery of palladium from acidic wastes

    International Nuclear Information System (INIS)

    Singh, Krishan Kant; Kanagare, Anant B.; Bairwa, K.K.; Manmohan Kumar; Bajaj, Parma N.; Ruhela, Ritesh; Singh, Ajoy K.; Hubli, Rajendra C.

    2014-01-01

    In the present study DTDGA extractant impregnated XAD16 polymeric beads (DTDGA- XAD16) were synthesized by wet chemical method and the beads were characterized by various techniques viz. FT-IR, Optical microscopy, SEM and TGA. The DTDGA-XAD 16 beads were evaluated for separation and recovery of palladium from high level waste solutions (HLW)

  3. Synthesis and characterization of new biopolymeric microcapsules containing DEHPA-TOPO extractants for separation of uranium from phosphoric acid solutions.

    Science.gov (United States)

    Outokesh, Mohammad; Tayyebi, Ahmad; Khanchi, Alireza; Grayeli, Fatemeh; Bagheri, Ghodrat

    2011-01-01

    A novel microcapsule adsorbent for separation of uranium from phosphoric acid solutions was developed by immobilizing the di(2-ethylhexyl) phosphoric acid-trioctyl phosphine oxide extractants in the polymeric matrix of calcium alginate. Physical characterization of the microcapsules was accomplished by scanning electron microscopy and thermogravimetric techniques. Equilibrium experiments revealed that both ion exchange and solvent extraction mechanisms were involved in the adsorption of [Formula: see text] ions, but the latter prevailed in a wider range of acid concentration. According to the results of kinetics study, at low acidity level, the rate controlling step was slow chemical reaction of [Formula: see text] ions with the microdroplets of extractant, whereas it changed to intraparticle diffusion at higher acid concentration. The study also attempted identification of the diffusion paths of the ions within the microcapsules, and the mechanism of change of mass transfer rate during the uptake process. The prepared microcapsules preserved their entire capacity after three cycles of adsorption, and their breakthrough behaviour was well fitted by a new formula derived from shrinking core model.

  4. Process for denitrating waste solutions containing nitric acid actinides simultaneously separating the actinides

    International Nuclear Information System (INIS)

    Gompper, K.

    1984-01-01

    The invention should reduce the acid and nitrate content of waste solutions containing nitric acid as much as possible, should reduce the total salt content of the waste solution, remove the actinides contained in it by precipitation and reduce the α radio-activity in the remaining solution, without having to worry about strong reactions or an increase in the volume of the waste solution. The invention achieves this by mixing the waste solution with diethyl oxalate at room temperature and heating the mixture to at least 80 0 C. (orig.) [de

  5. Impact of Sampling and Cellular Separation on Amino Acid Determinations in Drosophila Hemolymph.

    Science.gov (United States)

    Cabay, Marissa R; Harris, Jasmine C; Shippy, Scott A

    2018-04-03

    The fruit fly is a frequently used model system with a high degree of human disease-related genetic homology. The quantitative chemical analysis of fruit fly tissues and hemolymph uniquely brings chemical signaling and compositional information to fly experimentation. The work here explores the impact of measured chemical content of hemolymph with three aspects of sample collection and preparation. Cellular content of hemolymph was quantitated and removed to determine hemolymph composition changes for seven primary amine analytes. Hemolymph sampling methods were adapted to determine differences in primary amine composition of hemolymph collected from the head, antenna, and abdomen. Also, three types of anesthesia were employed with hemolymph collection to quantitate effects on measured amino acid content. Cell content was found to be 45.4 ± 22.1 cells/nL of hemolymph collected from both adult and larvae flies. Cell-concentrated fractions of adult, but not larvae, hemolymph were found to have higher and more variable amine content. There were amino acid content differences found between all three areas indicating a robust method to characterize chemical markers from specific regions of a fly, and these appear related to physiological activity. Methods of anesthesia have an impact on hemolymph amino acid composition related to overall physiological impact to fly including higher amino acid content variability and oxygen deprivation effects. Together, these analyses identify potential complications with Drosophila hemolymph analysis and opportunities for future studies to relate hemolymph content with model physiological activity.

  6. Process Intensification of Enzymatic Fatty Acid Butyl Ester Synthesis Using a Continuous Centrifugal Contactor Separator

    NARCIS (Netherlands)

    Ilmi, Miftahul; Abduh, Muhammad Yusuf; Hommes, Arne; Winkelman, Jozef; Hidayat, C.; Heeres, Hero

    2018-01-01

    Fatty acid butyl esters were synthesized from sunflower oil with 1-butanol using a homogeneous Rhizomucor miehei lipase in a biphasic organic (triglyceride, 1-butanol, hexane)– water (with enzyme) system in a continuous setup consisting of a cascade of a stirred tank reactor and a continuous

  7. Method for separation of Cs from acid solution dissolving radionuclides and microanalysis of solution with ICP-AES

    International Nuclear Information System (INIS)

    Kanazawa, Toru; Hidaka, Akihide; Kudo, Tamotsu; Nakamura, Takehiko; Fuketa, Toyoshi

    2004-06-01

    The VEGA (Verification Experiments of radionuclides Gas/Aerosol release) program is being performed at JAERI to understand mechanisms of radionuclides release from irradiated fuel during severe accidents. As a part of evaluation in the program, the mass balances of released and deposited FP (Fission Products) onto the test apparatus are estimated from gamma ray measurement for acid solution leached from the apparatus, but short-life nuclides are difficult to be measured because those in the VEGA fuel have been mostly depleted due to cooling for several years. Moreover, the radionuclides without emitting gamma rays and very small quantity of elements cannot be quantified by gamma ray measurement. Therefore, a microanalysis by ICP-AES (Inductively Coupled Plasma - Atomic Emission Spectrometry) for the acid solution leached from VEGA apparatuses is being applied to evaluate the released and deposited masses for those elements. Since Cs-134 and -137, which are major FP dissolved in the solution, have high intensity of gamma ray spectrum, they have to be removed from the solution before the microanalysis in order to avoid contamination of ICP system and to decrease exposure to gamma ray. In this report, methods for separation of Cs from acid solution were reviewed and the applicability of them to the ICP-AES analysis was discussed. The method for Cs separation using the inorganic ion exchanger, AMP (Ammonium Molybdate Phosphate) was applied to the solutions of cold and hot test and the effectiveness was examined. The results showed that more than 99.9% of Cs could be removed from the test solutions, and once removed Sb by AMP was recovered by using a complexing agent such as citric acid. Next, the method was applied to an acid solution leached from VEGA-3 apparatus, and ICP-AES analysis was performed for it. The analysis showed that amount of U, Sr and Zr were successfully quantified. Most of elements to be analyzed were measurable except for Sb, Ag and Sn, although

  8. Plasma surface tantalum alloying on titanium and its corrosion behavior in sulfuric acid and hydrochloric acid

    Science.gov (United States)

    Wei, D. B.; Chen, X. H.; Zhang, P. Z.; Ding, F.; Li, F. K.; Yao, Z. J.

    2018-05-01

    An anti-corrosion Ti-Ta alloy coating was prepared on pure titanium surface by double glow plasma surface alloying technology. Electrochemical corrosion test was applied to test the anti-corrosion property of Ti-Ta alloy layer. The microstructure and the phase composition of Ti-Ta alloy coating were detected before and after corrosion process by means of scanning electron microscope (SEM), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). The results showed that the Ta-Ti alloy layer has a thickness of about 13-15 μm, which is very dense without obvious defects such as pores or cracks. The alloy layer is composed mainly of β-Ta and α-Ti. The Ta alloy layer improves the anti-corrosion property of pure titanium. A denser and more durable TiO2 formed on the surface Ta-Ti alloy layer after immersing in strong corrosive media may account for the excellent corrosion resistant.

  9. SEPARATION OF p-AMINOBENZOIC ACID BY REACTIVE EXTRACTION. 1. MECHANISM AND INFLUENCING FACTORS

    Directory of Open Access Journals (Sweden)

    DAN CASCAVAL

    2008-09-01

    Full Text Available The comparative study on the reactive extraction of p-aminobenzoic acid with Amberlite LA-2 and D2EHPA in two solvents with different polarity (n-heptane and dichloromethane indicated that the extractant type and solvent polarity control the extraction mechanism. Thus, the reactive extraction with Amberlite LA-2 occurs by means of the interfacial formation of an aminic adduct with three extractant molecules in low-polar solvent, or of an salt with one extractant molecule in higher polar solvent. Similarly, the extraction with D2EHPA is based on the formation of an acidic adduct with two extractant molecules in n-heptane, or of a salt with one extractant molecule in dichloromethane. The most efficient extraction has been reached for the combination Amberlite LA-2-dichloromethane.

  10. Quantification of fatty acids as methyl esters and phospholipids in cheese samples after separation of triacylglycerides and phospholipids

    Energy Technology Data Exchange (ETDEWEB)

    Hauff, Simone [University of Hohenheim, Institute of Food Chemistry, Garbenstrasse 28, D-70599 Stuttgart (Germany); Vetter, Walter [University of Hohenheim, Institute of Food Chemistry, Garbenstrasse 28, D-70599 Stuttgart (Germany)], E-mail: w-vetter@uni-hohenheim.de

    2009-03-23

    Determination of the individual fatty acid composition of neutral- and phospholipids as well as the phospholipid content of dairy food and other foodstuffs are important tasks in life sciences. For these purposes, a method was developed for the separation of lipids (standards of triolein and diacylphosphatidylcholines as well as three cheese samples) by solid-phase extraction using a self-packed column filled with partly deactivated silica. Non-halogenated solvents were used for the elution of the lipid classes. Cyclohexane/ethyl acetate (1:1, v/v) served for the elution of neutral lipids, while polar lipids were eluted with three solvents (ethyl acetate/methanol, methanol, and methanol/water) into one fraction. The separated lipid fractions were transesterified and the individual fatty acids were quantified by using gas chromatography coupled to electron ionization mass spectrometry (GC/EI-MS) in the selected ion monitoring (SIM) mode. The recovery rate for standard phosphatidylcholines was {approx}90% and cross-contamination from neutral lipids was negligible. The method was applied to cheese samples. Quantitative amounts of individual fatty acids in the phospholipid fraction were <0.002-0.29% of total lipids from camembert, <0.002-0.12% of total lipids from mozzarella, and <0.002-0.18% of total lipids in a goat cream cheese. Differences in the fatty acid pattern of neutral and polar lipids were detected. The quantity of the fatty acids determined in the phospholipid fraction was divided by the factor 0.7 in order to convert the fatty acid content into the phospholipid content of the cheese samples. This factor is based on the contribution of 16:0 to dipalmitoylphosphatidylcholine (DPPC). The resulting DPPC equivalents (DPPC{sub eq}) were found to be representative for the average contribution of fatty acids to all classes of phospholipids in dairy products. Using this approach, the phospholipid content of lipids from mozzarella, camembert, and goat cream cheese

  11. Separation of transition-metal and 8-hydroxyquinoline-5-sulfonic acid complexes using ion-pair liquid chromatography

    International Nuclear Information System (INIS)

    Basova, E.M.; Demurov, L.M.; Shpigun, O.A.; Van Iyuchun'

    1994-01-01

    The retention of chelates of Fe(3), Cu(2), Co(2), Ni(2), Zn(2), Cd(2), Hg(2), and Pb)(2) with 8-hydroxyquinoline-5-sulfonic acid depending on the concentration of cetyltrimethylammonium bromide, acetonitrile, and pH of the mobile phase was investigated using the ion-pair reversed-phase high-performance liquid chromatography on separon C 18 . Under the optimum conditions, the separation of mixtures of Fe(3), Co(2) and Ni(2) is performed within 8 to 12 min

  12. Spectrographic determination of lanthanides in high-purity uranium compounds, after chromatographic separation by alumina-hydrofluoric acid

    International Nuclear Information System (INIS)

    Lordello, A.R.; Abrao, A.

    1979-01-01

    A method is presented for the determination of fourteen rare earth elements in high-purity uranium compounds by emission spectrography. The rare earths are chromatographically separated from uranium by using alumina-hydrofluoric acid. Lanthanum is used both as collector and internal standard. The technique of excitation involves a total consumption of the sample in a 17 ampere direct current arc. The range of determination is about 0.005 to 0.5 μg/g uranium. The coefficient of variation for Pr, Ho, Dy, Er, Tm, Lu, Gd and Tb amounts to 10%. (Author) [pt

  13. Separation behavior of octadecadienoic acid isomers and identification of cis- and trans-isomers using gas chromatography.

    Science.gov (United States)

    Shibamoto, Shigeaki; Gooley, Andrew; Yamamoto, Kouhei

    2015-01-01

    Using a strongly polar cyanopropyl capillary column we have investigated the gas chromatography (GC) separation behaviors of 24 octadecadienoic acid methyl ester (18:2ME) isomers compared against saturated methyl stearate (18:0ME) and arachidic acid methyl ester (20:0ME), and the dependency on the GC column temperature. The 24 isomers were obtained by performing cis-to trans-isomerization of six regioisomers: five of the 18:2ME isomers were prepared by the partial reduction of methyl α-linolenate and methyl γ-linolenate C18 trienoic acids with different double bond positions, whereas the sixth isomer, 18:2ME (c5, c9), was obtained from a raw constituent fatty acid methyl ester (FAME) sample extracted from Japanese yew seeds. There are no reference standards commercially available for 18:2ME isomers, and in elucidating the elution order of these isomers this study should help the future identification of cis- and trans-type of 18:2ME. We also report the identification method of cis- and trans-type of FAME using equivalent chain lengths and attempt the identification of cis- and trans-type of 18:2ME isomers from partially hydrogenated canola oil.

  14. Separation of bismuth from gram amounts of thallium and silver by cation-exchange chromatography in nitric acid.

    Science.gov (United States)

    Meintjies, E; Strelow, F W; Victor, A H

    1987-04-01

    Traces and small amounts of bismuth can be separated from gram amounts of thallium and silver by successively eluting these elements with 0.3M and 0.6M nitric acid from a column containing 13 ml (3 g) of AG50W-X4, a cation-exchanger (100-200 mesh particle size) with low cross-linking. Bismuth is retained and can be eluted with 0.2M hydrobromic acid containing 20% v/v acetone, leaving many other trace elements absorbed. Elution of thallium is quite sharp, but silver shows a small amount of tailing (less than 1 gmg/ml silver in the eluate) when gram amounts are present, between 20 and 80 mug of silver appearing in the bismuth fraction. Relevant elution curves and results for the analysis of synthetic mixtures containing between 50 mug and 10 mg of bismuth and up to more than 1 g of thallium and silver are presented, as well as results for bismuth in a sample of thallium metal and in Merck thallium(I) carbonate. As little as 0.01 ppm of bismuth can be determined when the separation is combined with electrothermal atomic-absorption spectrometry.

  15. Separation of phenolic acids from sugarcane rind by online solid-phase extraction with high-speed counter-current chromatography.

    Science.gov (United States)

    Geng, Ping; Fang, Yingtong; Xie, Ronglong; Hu, Weilun; Xi, Xingjun; Chu, Qiao; Dong, Genlai; Shaheen, Nusrat; Wei, Yun

    2017-02-01

    Sugarcane rind contains some functional phenolic acids. The separation of these compounds from sugarcane rind is able to realize the integrated utilization of the crop and reduce environment pollution. In this paper, a novel protocol based on interfacing online solid-phase extraction with high-speed counter-current chromatography (HSCCC) was established, aiming at improving and simplifying the process of phenolic acids separation from sugarcane rind. The conditions of online solid-phase extraction with HSCCC involving solvent system, flow rate of mobile phase as well as saturated extent of absorption of solid-phase extraction were optimized to improve extraction efficiency and reduce separation time. The separation of phenolic acids was performed with a two-phase solvent system composed of butanol/acetic acid/water at a volume ratio of 4:1:5, and the developed online solid-phase extraction with HSCCC method was validated and successfully applied for sugarcane rind, and three phenolic acids including 6.73 mg of gallic acid, 10.85 mg of p-coumaric acid, and 2.78 mg of ferulic acid with purities of 60.2, 95.4, and 84%, respectively, were obtained from 150 mg sugarcane rind crude extracts. In addition, the three different elution methods of phenolic acids purification including HSCCC, elution-extrusion counter-current chromatography and back-extrusion counter-current chromatography were compared. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Determination of diphenylarsinic acid, phenylarsonic acid and inorganic arsenic in drinking water by graphite-furnace atomic-absorption spectrometry after simultaneous separation and preconcentration with solid-phase extraction disks.

    Science.gov (United States)

    Hagiwara, Kenta; Inui, Tetsuo; Koike, Yuya; Nakamura, Toshihiro

    2013-01-01

    A simple method of graphite-furnace atomic-absorption spectrometry (GFAAS) after solid-phase extraction (SPE) was developed for the determination of diphenylarsinic acid (DPAA), phenylarsonic acid (PAA), and inorganic arsenic (iAs) in drinking water. This method involves the simultaneous collection of DPAA, PAA, and iAs using three stacked SPE disks, i.e., an Empore SDB-XD disk (the upper layer), an activated carbon disk (the middle layer), and a Cation-SR disk loaded with Zr and Ca (ZrCa-CED; the lower layer). A 200-mL aqueous sample was adjusted to pH 3 with nitric acid and passed through the SPE disks at a flow rate of 15 mL min(-1), to concentrate DPAA on the SDB-XD disk, PAA on the activated carbon disk, and iAs on the ZrCa-CED. The As compounds were eluted from the disks with 10 mL of ethanol containing 0.5 mol L(-1) ammonia solution for DPAA, 20 mL of 1 mol L(-1) ammonia solution for PAA, and 20 mL of 6 mol L(-1) hydrochloric acid for iAs. The eluates of DPAA, PAA, and iAs were diluted to 20, 25, and 25 mL, respectively, with deionized water, and then analyzed by GFAAS. The detection limits of As (three-times the standard deviation (n = 3) of the blank values) were 0.13 and 0.16 μg L(-1) at enrichment factors of 10 and 8, respectively, using a 200-mL water sample. Spike tests with 2 μg (10 μg L(-1)) of DPAA, PAA, and iAs in 200 mL of tap water and bottled drinking water showed good recoveries (96.1-103.8%).

  17. Application of liquid-liquid extraction in separation of rare earths [Paper No. : V-6

    International Nuclear Information System (INIS)

    Deshpande, S.M.; Krishnan, N.P.K.; Murthy, T.K.S.; Swaminathan, T.V.

    1979-01-01

    The rare earths consist of fifteen elements which have very similar chemical properties and are difficult to separate from each other. Since they exist together in all naturally occurring minerals their separation is one of the important and difficult aspects of their technology. Liquid-liquid extraction has proved to be an efficient technique for their separation. The two important extraction systems that find practical and large scale application, the nitric acid + tri-n-butyl phosphate, and mineral acid (particularly hydrochloric acid) + organo phosphoric acid (like di-2-ethyl hexyl phosphoric acid), are briefly reviewed. The factors affecting the extraction and separation of rare earths in the two systems are discussed. On an industrial scale the extraction process is very often employed for an initial concentration of the desired rare earths from complex mixtures. The final purification is generally achieved by the ion exchange method. The utility of the solvent extraction process for the upgrading of selected rare earths-europium, samarium and gadolinium-from a mixed rare earth chloride, derived from monazite, is illustrated by the work carried out in this laboratory and pilot plant operation at the Alwaye plant of M/s. Indian Rare Earths Ltd. (author)

  18. Limiting factors in the pro-oxidants production with the use of fatty acids mixture separated from soapstock

    Directory of Open Access Journals (Sweden)

    V. I. Korchagin

    2017-01-01

    Full Text Available The synthesis of prooxidants - carboxylates of variable valence metals (iron, copper and cobalt was carried with the use of a mixture of fatty acids with an acid number of 100-120 mg KOH / g, separated from the soapstock, which is a liquid waste of oil- and fatproduction. Carboxylates of variable valency metals were synthesized in a high-energy ultrasound field using a generator USG13-0.1 / 22. Mixed thermal and ultrasound effects contribute to an increase in the yield of metal carboxylates. The maximum yield of prooxidates was over 84% (by weight.When carrying out the synthesis of carboxylates of metals of variable valence, ion activity was revealed in the exchange reactions with sodium salts on the basis of a mixture of fatty acids in the following order: Co2+ >Cu2+ >Fe2+. The synthesis of carboxylates of variable valence metals is a multifactor system and depends on temperature regimes, metal activity, viscosity and structural characteristics of a fatty acids mixture. The formation of metal carboxylates was carried out in a water-alcohol medium at a high rate for the heterogeneous systems, which are the exchange reactions between strong alkali salts and carbon acids. It should be noted that an increase in the synthesis temperature above 60 ° C with simultaneous ultrasound exposure reduced the yield of products and influenced the quality composition of the carboxylates of metals of variable valency.We should also take into account that ultrasound impact allows to obtain a prooxidant of the required dispersity and it is extremely important in the production of multifunctional and targeted additives. The use of ultrasound fields of high intensity in the synthesis of carboxylates of metals of variable valence is preferable in a less viscous medium due to the better ultrasound spread

  19. Extraction of Collagen from Chicken Feet with Various Acidic Solutions and Soaking Time

    Directory of Open Access Journals (Sweden)

    Prayitno Prayitno

    2007-05-01

    Full Text Available The objective of this research was to know the ability of various acidic solutions on dissolving collagen  chicken feet, with different soaked time.  Each acid 5 percent (v/v, collagen extraction was done by washing chicken feet and then cutted into small pieces and finally grinded.  Every 100 gram treatment was soaked in acetic acid (a1, citric acid (a2, lactic acid (a3 and hydrochloric acid (a4, for 12, 24 and 36 hours.  Precipitated collagen in the filtrate was 5 percent NaOH to reach the neutral pH (pH 7.  Collagen precipitate was separated by filtration usingfilter paper and then  rendement was calculated, HPLC was used to determin amino acid composition, and SDS-PAGE was use determin the type of collagen.  This experiment use factorial completely randomized design (CRD 4 x 3 and three time replication.   Result showed that lactic acid has highest capability to dissolve collagen, while citric acid the lowest.  Combination of acid solution and soaking time had significant (P<0.01 effect on dissolving collagen of chicken feet.  Extracted collagen in all acid solution, hassame amino acid, composition but different in percentage of amino acid molecules.  Collagen type in treatment combination was the same, but for soaking time of 36 hours revealed some peptide band.  Lactic acid had highest capability of collagen extraction in chicken feet than citric acid, acetic acid and hydrochloric acid with soaking time of 12, 24 and 36 hours.  It was estimated that extracted collagen can be grouped to type I consisted of two chain of a1. (Animal Production 9(2: 99-104 (2007   Key Words : Chicken feet, acids, soaking time, collagen

  20. Iminodiacetic acid functionalised organopolymer monoliths: application to the separation of metal cations by capillary high-performance chelation ion chromatography.

    Science.gov (United States)

    Moyna, Áine; Connolly, Damian; Nesterenko, Ekaterina; Nesterenko, Pavel N; Paull, Brett

    2013-03-01

    Lauryl methacrylate-co-ethylene dimethacrylate monoliths were polymerised within fused silica capillaries and subsequently photo-grafted with varying amounts of glycidyl methacrylate (GMA). The grafted monoliths were then further modified with iminodiacetic acid (IDA), resulting in a range of chelating ion-exchange monoliths of increasing capacity. The IDA functional groups were attached via ring opening of the epoxy group on the poly(GMA) structure. Increasing the amount of attached poly(GMA), via photo-grafting with increasing concentrations of GMA, from 15 to 35%, resulted in a proportional and controlled increase in the complexation capacity of the chelating monoliths. Scanning capacitively coupled contactless conductivity detection (sC(4)D) was used to characterise and verify homogenous distribution of the chelating ligand along the length of the capillaries non-invasively. Chelation ion chromatographic separations of selected transition and heavy metals were carried out, with retention factor data proportional to the concentration of grafted poly(GMA). Average peak efficiencies of close to 5,000 N/m were achieved, with the isocratic separation of Na, Mg(II), Mn(II), Co(II), Cd(II) and Zn(II) possible on a 250-mm-long monolith. Multiple monolithic columns produced to the same recipes gave RSD data for retention factors of ions). The monolithic chelating ion-exchanger was applied to the separation of alkaline earth and transition metal ions spiked in natural and potable waters.

  1. Advanced Acid Gas Separation Technology for Clean Power and Syngas Applications

    Energy Technology Data Exchange (ETDEWEB)

    Amy, Fabrice [Air Products and Chemicals Inc., Allentown, PA (United States); Hufton, Jeffrey [Air Products and Chemicals Inc., Allentown, PA (United States); Bhadra, Shubhra [Air Products and Chemicals Inc., Allentown, PA (United States); Weist, Edward [Air Products and Chemicals Inc., Allentown, PA (United States); Lau, Garret [Air Products and Chemicals Inc., Allentown, PA (United States); Jonas, Gordon [Air Products and Chemicals Inc., Allentown, PA (United States)

    2015-06-30

    Air Products has developed an acid gas removal technology based on adsorption (Sour PSA) that favorably compares with incumbent AGR technologies. During this DOE-sponsored study, Air Products has been able to increase the Sour PSA technology readiness level by successfully operating a two-bed test system on coal-derived sour syngas at the NCCC, validating the lifetime and performance of the adsorbent material. Both proprietary simulation and data obtained during the testing at NCCC were used to further refine the estimate of the performance of the Sour PSA technology when expanded to a commercial scale. In-house experiments on sweet syngas combined with simulation work allowed Air Products to develop new PSA cycles that allowed for further reduction in capital expenditure. Finally our techno economic analysis of the use the Sour PSA technology for both IGCC and coal-to-methanol applications suggests significant improvement of the unit cost of electricity and methanol compared to incumbent AGR technologies.

  2. Recovery of fluorine, uranium, and rare earth metal values from phosphoric acid by-product brine raffinate

    International Nuclear Information System (INIS)

    Wamser, C.A.; Bruen, C.P.

    1976-01-01

    A method for recovering substantially all of the fluorine and uranium values and at least 90 percent of the rare earth metal values from brine raffinate obtained as by-product in the production of phosphoric acid by the hydrochloric acid decomposition of tricalcium phosphate minerals is described. A basically reacting compound is added to the brine raffinate to effect a pH 9 or greater, whereby fluorine, uranium and rare earth metal values are simultaneously precipitated. These values may then be separately recovered from the precipitate by known processes

  3. Simultaneous separation and quantitation of amino acids and polyamines of forest tree tissues and cell cultures within a single high-performance liquid chromatography run using dansyl derivatization

    Science.gov (United States)

    Rakesh Minocha; Stephanie Long

    2004-01-01

    The objective of the present study was to develop a rapid HPLC method for simultaneous separation and quantitation of dansylated amino acids and common polyamines in the same matrix for analyzing forest tree tissues and cell cultures. The major modifications incorporated into this method as compared to previously published HPLC methods for separation of only dansyl...

  4. Separation of Be and Al for AMS using single-step column chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Binnie, Steven A., E-mail: sbinnie@uni-koeln.de [Institute for Geology und Mineralogy, University of Cologne, 4-6 Greinstrasse, Cologne D-50939 (Germany); Dunai, Tibor J.; Voronina, Elena; Goral, Tomasz [Institute for Geology und Mineralogy, University of Cologne, 4-6 Greinstrasse, Cologne D-50939 (Germany); Heinze, Stefan; Dewald, Alfred [University of Cologne, Institut für Kernphysik, Zülpicher Str. 77, Cologne D-50937 (Germany)

    2015-10-15

    With the aim of simplifying AMS target preparation procedures for TCN measurements we tested a new extraction chromatography approach which couples an anion exchange resin (WBEC) to a chelating resin (Beryllium resin) to separate Be and Al from dissolved quartz samples. Results show that WBEC–Beryllium resin stacks can be used to provide high purity Be and Al separations using a combination of hydrochloric/oxalic and nitric acid elutions. {sup 10}Be and {sup 26}Al concentrations from quartz samples prepared using more standard procedures are compared with results from replicate samples prepared using the coupled WBEC–Beryllium resin approach and show good agreement. The new column procedure is performed in a single step, reducing sample preparation times relative to more traditional methods of TCN target production.

  5. Separation of Be and Al for AMS using single-step column chromatography

    Science.gov (United States)

    Binnie, Steven A.; Dunai, Tibor J.; Voronina, Elena; Goral, Tomasz; Heinze, Stefan; Dewald, Alfred

    2015-10-01

    With the aim of simplifying AMS target preparation procedures for TCN measurements we tested a new extraction chromatography approach which couples an anion exchange resin (WBEC) to a chelating resin (Beryllium resin) to separate Be and Al from dissolved quartz samples. Results show that WBEC-Beryllium resin stacks can be used to provide high purity Be and Al separations using a combination of hydrochloric/oxalic and nitric acid elutions. 10Be and 26Al concentrations from quartz samples prepared using more standard procedures are compared with results from replicate samples prepared using the coupled WBEC-Beryllium resin approach and show good agreement. The new column procedure is performed in a single step, reducing sample preparation times relative to more traditional methods of TCN target production.

  6. Desorption of uranium from titanium-activated carbon composite adsorbent with acidic eluent, 2

    International Nuclear Information System (INIS)

    Hirotsu, Takahiro; Fujii, Ayako; Sakane, Kohji; Katoh, Shunsaku; Sugasaka, Kazuhiko

    1984-01-01

    The desorption of uranium from the granular titanium-activated carbon composite adsorbent (concentration of uranium: 25.5 mg/1-Ad), which adsorbed uranium from natural sea water, was examined by the column process with acidic eluent at room temperature. The column operation was able to be carried out without destruction of the granular adsorbent by the generation of the carbon dioxide, and free from disturbance of the eluent flow by precipitate of calcium sulfate dihydrate with sulfuric acid eluent. The amount of acid consumption by the adsorbent was 0.87 eq/1-Ad. The alkaline earth metals were eluted in the range of elution volume below 2 1/1-Ad, whereas uranium, iron, and titanium were eluted above 2 1/1-Ad. Therefore, uranium was separable from the alkaline earth metals which were adsorbed in the most quantity in the adsorbent. In the range of elution volume 2 to 12 1/1-Ad, the percentage of desorbed uranium and the concentration ratio of uranium were 80 %, 680 with 0.5 N sulfuric acid, and 59 %, 490 with 0.5 N hydrochloric acid, respectively. The percentage of dissolved titanium (DTI) was 0.3 % with 0.5 N sulfuric acid, 0.26 % with 0.5 N hydrochloric acid in the same range. (author)

  7. On the Integration Role of Solvents in Process Synthesis-Design-Intensification: Application to DMC/MeOH separation

    DEFF Research Database (Denmark)

    Gani, Rafiqul; Babi, Deenesh Kavi

    2015-01-01

    extractive distillation. In extractive distillation the solvent affects the relative volatility of the two key compounds to be separated. In other words, for a two column distillation sequence configuration, the lighter boiling compound is obtained as the top product of the first distillation column...... of the better replacements for methyl tert-butyl ether. Methanol (MeOH) is used as a common raw material in the production of DMC, for example, using phosgene with hydrochloric acid as the by-product, using carbon monoxide and oxygen with water as the by-product, using a cyclic carbonate with a glycol as the by...... the best separation system, with the focus on solvent generation, screening and verification for extractive distillation for the separation of MeOH and DMC. The three stage approach will be presented and it will be shown that existing solvent candidates found in the literature are already generated...

  8. Extraction and Separation of Uranium (VI) and Thorium (IV) Using Tri-n-dodecylamine Impregnated Resins

    International Nuclear Information System (INIS)

    Metwally, E.; Saleh, A.Sh.; El-Naggar, H.A.

    2005-01-01

    Extraction of U(VI) and Th(IV) from chloride and nitrate solutions with tri-n- dodecylamine impregnated on Amberlite XAD4, was investigated. The distribution of U(VI) and Th(IV) was studied at different concentrations of acid, salting-out agent, extractant, aqueous metal ion and other parameters. Absorption spectral studies have been investigated for uranium species in both aqueous HCl solution and the resin phase. From these studies, it is suggested that the tetrachloro complex of U(VI) is formed in the extraction of uranium (VI) from hydrochloric acid solutions by TDA impregnated resin. Stripping of the extracted U(VI) and Th(IV) was assayed with HCl and HNO 3 . Finally, the separation of uranium from thorium and fission products in HCl media was achieved

  9. Acid in perchloroethylene scrubber solutions used in HTGR fuel preparation processes. Analytical chemistry studies

    International Nuclear Information System (INIS)

    Lee, D.A.

    1979-02-01

    Acids and corrosion products in used perchloroethylene scrubber solutions collected from HTGR fuel preparation processes have been analyzed by several analytical methods to determine the source and possible remedy of the corrosion caused by these solutions. Hydrochloric acid was found to be concentrated on the carbon particles suspended in perchloroethylene. Filtration of carbon from the scrubber solutions removed the acid corrosion source in the process equipment. Corrosion products chemisorbed on the carbon particles were identified. Filtered perchloroethylene from used scrubber solutions contained practically no acid. It is recommended that carbon particles be separated from the scrubber solutions immediately after the scrubbing process to remove the source of acid and that an inhibitor be used to prevent the hydrolysis of perchloroethylene and the formation of acids

  10. Application of hydrochloric cyclopentolate eye drops in the mydriasis test and optometry for children with hyperopia

    Directory of Open Access Journals (Sweden)

    Hong-Ping Yin

    2016-02-01

    Full Text Available AIM:To observe and study the comprehensive application effect of hydrochloric cyclopentolate eye drops in the mydriasis test and optometry for children with hyperopia.METHODS:Eighty-four children with hyperopia who were intervened with mydriasis test and optometry in our hospital from February 2014 to March 2015 were selected as the research object,and they were intervened with mydriasis test and optometry by tropicamide or hydrochloric cyclopentolate eye drops. The diopter, pupil diameter and residual regulation before administration and at different time after administration of the two methods were compared,and the detected results of the two groups with different severity degree were compared too.RESULTS:The diopter, pupil diameter and residual regulation before administration of the two eye drops had no significant differences(all P>0.05,while the residual regulation after using hydrochloric cyclopentolate eye drops at 20, 40, 60min and 24h were all smaller than those after using tropicamide(all PP>0.05. The pupil diameter of the two groups at 48h after administration both had no significant differences to those before administration(all P>0.05.CONCLUSION:The comprehensive application effect of hydrochloric cyclopentolate eye drops in the mydriasis test and optometry of children with hyperopia is better,and its paralysis effect for ciliaris is obvious.

  11. Separation and determination of strontium-90 in burnout nuclear fuel

    International Nuclear Information System (INIS)

    Khermann, A.; Katsvinkel', I.

    1975-01-01

    Developed was a simple and selective chromatographic method of the separation of strontium-90, by the content of which it is possible to judge about the degree of nuclear fuel burnup. Among the studied ion exchangers for strontium separation the best results are exhibited by strongly acidic organic cationite, i.e. vofatite (on the base of styrene, 8%-divinylbenzene) in the H + form. Elution was performed by hydrochloric or oxalic acids. The method allows to achieve a high degree of Sr-90 purification from other fission products. Using the method the Sr-90 content was determined in burnup fuel of the fuel elements of EK-10 type. At the fuel storage period less than 2 years it becomes necessary to determine both Sr-90 and Sr-89. Determination of Sr-90 in the presence of Sr-89 was made by daughter product of Sr-90 - Y-90, which is separated in ion-exchange coloumn. Some other methods of Sr-90 determination in the presence of Sr-89 are noted

  12. Batch Simulation of Rare Earths Extractive Separation by Di (2-Ethylhexyl) Phosphoric Acid and Tributylphosphate in Kerosene

    International Nuclear Information System (INIS)

    Kraikaew, Jarunee; Srinuttakul, Wanee

    2004-01-01

    Liquid-liquid extraction is applied to separate individual rare earths. In this research, 6-stage continuous countercurrent solvent extraction was simulated to extract rare earths from rare earth nitrate solution, which was obtained from monazite processing, to estimate the possible optimum operating conditions for pilot or industrial plants. The solvent(S) per feed(F) ratio (S/F) was varied from 1 to 3. The organic are 1.0 and 1.5 Molars (M) Di (2-ethylhexyl) phosphoric acid (D2EHPA) in kerosene. 50% tributylphosphate (TBP) in kerosene was applied for comparison. It was found that D2EHPA was a good extracting agent for heavy rare earths while TBP extracted well both light and heavy rare earths. After extraction with TBP and D2EHPA, the extraction efficiency at solvent per feed ratio (S/F) =2 and 3 showed a slight difference. S/F =2 was selected commercially for operation

  13. The potential for disinfection of separated faecal matter by urea and by peracetic acid for hygienic nutrient recycling.

    Science.gov (United States)

    Vinnerås, B; Holmqvist, A; Bagge, E; Albihn, A; Jönsson, H

    2003-09-01

    No efficient, reliable, and scale independent disinfection methods for toilet waste are available today for safe recycling of plant nutrients. Therefore, two chemical treatment methods, addition of urea or of PAA (a quaternary mixture of 15% peracetic acid, 15% hydrogen peroxide and 30% acetic acid), were evaluated for disinfection of faecal matter.Degradation of the added urea resulted in 30 g of ammonia nitrogen per kilogram of treated matter and a pH increase to approximately 9.3. This produced an efficient disinfection of E. coli, Enterococcus spp., and Salmonella spp. within 3 weeks (>6log(10) reduction) and a reduction of the chemical resistant Salmonella typhimurium 28b phage, corresponding to a decimal reduction within 7.5 days. No viable Ascaris suum eggs were found after 50 days of treatment. No reduction of spore forming Clostridia spp. was observed. Urea treatment proved to be efficient for disinfection of source separated faecal matter in a scale independent method used for safe recycling of nutrients found in the faecal matter.PAA reduced all of the above indicator organisms within 12 h after application. For this faecal material, with a dry matter content of approximately 10%, an addition of 0.5-1% of PAA (active substance, corresponding to 3.3-6.7% of the Proxitane 15 used) was required before no viable organisms were found in the material. However, this was not tested for the A. suum. No viable spore-forming bacteria or phages were detected. A high rate of bacteria regrowth occurred at 0.15% dosage and 5 days of treatment. PAA is an efficient alternative for disinfection of separated faeces if a rapid treatment is needed.

  14. [Separation of p-aminobenzenearsonic acid and its oxide by ion-pair reversed-phase high performance liquid chromatography].

    Science.gov (United States)

    Kang, J; Ma, X; Meng, L; Ma, D

    1999-05-01

    To study the separation of p-aminobenzenearsonic acid (PABAA) and its oxide, p-aminophenylarsine oxide (PAPAO), both the absorption spectra were scanned at the wavelengths from 200 nm to 380 nm. PABAA had absorption maximum at 254 nm and PAPAO 258 nm. The effects of salt concentration, column temperature, methanol and ion-pair agent concentrations on the capacity factor were investigated. Compounds of high polarity showed almost no retention on reversed-phase column; as the volume fraction of the methanol decreased from 90% to 10%, the retention time of PABAA gradually increased with broad peak, and partially eluted when methanol volume fraction being below 20%. With temperature rising, the retention time of PABAA was decreased. But PABAA capacity factor can be increased by selecting an appropriate salt concentration for the mobile phase. The cetyltrimethyl and tetrabutyl ammonium ions were separately added as ion-pair agents to the mobile phase containing methanol in phosphate buffer of 10 mmol/L, the changes of retention time were observed. The mechanism of retention based on reversed phase ion-pair model is proposed. Besides, the retention behaviour is also influenced by size exclusion in stationary phase as well as polar interactions with residual silanol group on the silica surface.

  15. Separation of rare earths by means of acid organophosphorous compounds. Structure-activity study by molecular simulation

    International Nuclear Information System (INIS)

    Fourcot, Fabrice

    1991-01-01

    The increasing number of industrial applications of rare earths has resulted in an increased demand in purified rare earths whereas their separation is difficult due to their high chemical similarity. The search for a better separation leads to the search for more selective extraction agents. Organophosphorous compounds appear to be the most selective. As the search for new extraction agents resulting in high lanthanide extraction efficiency or in a better selectivity between rare earths has been mainly empiric, this research thesis aims at developing a molecular simulation method which allows the number of molecules to be synthesized and tested to be reduced. After having briefly recalled general knowledge on liquid-liquid extraction and on rare earths, and described calculation methods (quantum methods, methods based on molecular mechanics, conformational analysis, methods of charge calculation), the author proposes a critical review of literature related to rare earth liquid-liquid extraction by organophosphorous acids with respect to the used extraction agent. The molecular modelling issue is then addressed by describing ways to apply it to extraction problems, faced problems, brought solutions and obtained results

  16. Extraction and separation of U(VI and Th(IV from hydrobromic acid media using Cyanex-923 extractant

    Directory of Open Access Journals (Sweden)

    Ghag Snehal M.

    2010-01-01

    Full Text Available A systematic study of the solvent extraction of uranium(VI and thorium(IV from hydrobromic acid media was performed using the neutral phosphine oxide extractant Cyanex-923 in toluene. These metal ions were found to be quantitatively extracted with Cyanex-923 in toluene in the acidity range 5x10-5-1x10-4 M and 5x10-5-5x10-3 M, respectively, and they are stripped from the organic phase with 7.0 M HClO4 and 2.0- 4.0 M HCl, respectively. The effect of the equilibrium period, diluents, diverse ions and stripping agent on the extraction of U(VI and Th(IV was studied. The stoichiometry of the extracted species of these metal ions was determined based on the slope analysis method. The extraction reactions proceed by solvation and their probable extracted species found in the organic phase were UO2Br2•2Cyanex-923 and ThBr4•2Cyanex-923. Based on these results, a sequential procedure for their separation from each other was developed.

  17. Enantiomeric separation of some demethylated analogues of clofibric acid by capillary zone electrophoresis and nano-liquid chromatography.

    Science.gov (United States)

    Fantacuzzi, Marialuigia; Bettoni, Giancarlo; D'Orazio, Giovanni; Fanali, Salvatore

    2006-03-01

    The enantiomeric separation of some demethylated analogues of clofibric acid, namely 2-(6-chloro-benzothiazol-2-ylsulfanyl)-, 2-(6-methoxy-benzothiazol-2-ylsulfanyl)-, 2-(quinolin-2-yloxy)-, 2-(6-chloro-quinolin-2-yloxy)-, 2-(7-chloro-quinolin-4-yloxy)-propionic acid (compounds A-E, respectively), has been studied by CZE and nano-LC using for the first technique two beta-CD derivatives and vancomycin added to the BGE and vancomycin-modified silica particles for the second one, with the aim to find the optimum experimental conditions for the baseline resolution. The type and the concentration of the chiral selector added to the BGE, the buffer pH, the type of organic modifier and its concentration, the capillary temperature and the applied voltage played a very important role in the enantioresolution of the analysed compounds. The use of 6-monodeoxy-6-monoamino-beta-CD allowed to achieve baseline resolution of four of five clofibric acid derivatives in less than 10 min while heptakis-(2,3,6-tri-O-methyl)-beta-CD partially resolved the same compounds in their enantiomers. Employing vancomycin as the chiral selector in CZE, the counter-current partial filling method was chosen achieving baseline resolution of four analytes. All the studied compounds were enantioresolved employing a capillary column packed with vancomycin stationary phase by nano-LC, and the resolution was strongly influenced by the concentration of the organic modifier and by the pH of the mobile phase. The best results were achieved at pH 4.5 in presence of 60% of methanol (MeOH). However, longer analysis times were observed in the experiments carried out by nano-LC.

  18. Highly efficient high-performance liquid chromatographic separation of xylene isomers and phthalate acid esters on a homemade DUT-67(Zr) packed column.

    Science.gov (United States)

    Chen, Sha; Li, Xiao-Xin; Feng, Fan; Li, Sumei; Han, Jia-Hui; Jia, Zi-Yi; Shu, Lun; Somsundaran, P; Li, Jian-Rong

    2018-04-16

    In this study, the baseline separations of xylene isomers and phthalate acid esters on a homemade DUT-67(Zr) packed column were achieved, respectively. The high selectivity for xylene isomers and phthalate acid esters was obtained with the increase of temperature and decrease of the retention time. The hydrophobicity of xylene isomers and phthalate acid esters caused the different separation time on the DUT-67(Zr) packed column. The relative standard deviation values of retention time, peak area, peak height and half peak width for five repeat separation of the xylene isomers were 0.26-0.35, 2.11-2.26, 1.51-2.03, and 0.29-0.77%, and the values of the phthalate acid esters on DUT-67(Zr) column were 0.1-0.4, 4.4-5.2, 3.9-6.3, and 0.6-2.1%, respectively. The thermodynamic properties indicated that the separation of xylene isomers was controlled by ΔH and ΔS, but the separation of phthalate acid esters was mainly controlled by ΔS. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  19. Separations chemistry

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Results of studies on the photochemistry of aqueous Pu solutions and the stability of iodine in liquid and gaseous CO 2 are reported. Progress is reported in studies on: the preparation of macroporous bodies filled with oxides and sulfides to be used as adsorbents; the beneficiation of photographic wastes; the anion exchange adsorption of transition elements from thiosulfate solutions; advanced filtration applications of energy significance; high-resolution separations; and, the examination of the separation agents, octylphenylphosphoric acid (OPPA) and trihexyl phosphate (THP)

  20. Energy-dispersive X-ray fluorescence analysis of traces of heavy metals (Mn, Fe, Co, Ni, Cu, Zn, Ta, Pb, U) in mineral waters after separation on the cellulose-exchanger Hyphan

    International Nuclear Information System (INIS)

    Burba, P.; Lieser, K.H.

    1979-01-01

    Trace elements in mineral water are separated in small columns on the cellulose-exchanger Hyphan, eluted by diluted hydrochloric acid, bound on 100 mg of Hyphan by shaking and determined by energy-dispersive X-ray fluorescence. The following heavy metals can be analysed quantitatively if present in water in concentrations >= 1 ppb: Mn, Fe, Co, Ni, Cu, Zn, Ta, Pb and U. Several commercial mineral waters, a sodium chloride spring and seawater were analyzed for trace elements. The results obtained by X-ray fluorescence and by atomic absorption agree within the limits of error. (orig.) [de

  1. Effect of thermal annealing on a novel polyamide–imide polymer membrane for aggressive acid gas separations

    KAUST Repository

    Vaughn, Justin T.

    2012-05-01

    A fluorinated, 6FDA based polyamide-imide is investigated for the purification of CH 4 from CO 2 and H 2S containing gas streams. Dense polymer films were thermally annealed and showed that increased annealing temperatures at constant annealing time caused transport behavior that does not resemble physical aging. Free volume increased after annealing at 200°C for 24h relative to annealing at 150°C for the same time. CO 2 and CH 4 permeabilities and diffusivities did not decrease as a result of the higher annealing temperature, and in fact, were shown to increase slightly. A change to the intrinsic microstructure that cannot be described by simple, densification based physical aging is hypothesized to be the reason for this trend. Furthermore, annealing increased CO 2 induced plasticization resistance and a temperature of 200°C was shown to have the greatest effect on plasticization suppression. Annealing at 200°C for 24h suppressed pure gas CO 2 plasticization up to 450psia. Fluorescence spectroscopy revealed increased intramolecular charge transfer, which is presumably due to increased electron conjugation over the N-phenyl bond. Additionally, intermolecular charge transfer increased with thermal annealing, as inferred from fluorescence intensity measurements and XRD patterns. 50/50 CO 2/CH 4 mixed gas permeation measurements reveal stable separation performance up to 1000psia. Ternary mixed gas feeds containing toluene/CO 2/CH 4 and H 2S/CO 2/CH 4 show antiplasticization, but more importantly, selectivity losses due to plasticization did not occur up to 900psia of total feed pressure. These results show that the polyamide-imide family represents a promising class of separation materials for aggressive acid gas purifications. © 2012 Elsevier B.V.

  2. Effect of thermal annealing on a novel polyamide–imide polymer membrane for aggressive acid gas separations

    KAUST Repository

    Vaughn, Justin T.; Koros, William J.; Johnson, J.R.; Karvan, Oguz

    2012-01-01

    A fluorinated, 6FDA based polyamide-imide is investigated for the purification of CH 4 from CO 2 and H 2S containing gas streams. Dense polymer films were thermally annealed and showed that increased annealing temperatures at constant annealing time caused transport behavior that does not resemble physical aging. Free volume increased after annealing at 200°C for 24h relative to annealing at 150°C for the same time. CO 2 and CH 4 permeabilities and diffusivities did not decrease as a result of the higher annealing temperature, and in fact, were shown to increase slightly. A change to the intrinsic microstructure that cannot be described by simple, densification based physical aging is hypothesized to be the reason for this trend. Furthermore, annealing increased CO 2 induced plasticization resistance and a temperature of 200°C was shown to have the greatest effect on plasticization suppression. Annealing at 200°C for 24h suppressed pure gas CO 2 plasticization up to 450psia. Fluorescence spectroscopy revealed increased intramolecular charge transfer, which is presumably due to increased electron conjugation over the N-phenyl bond. Additionally, intermolecular charge transfer increased with thermal annealing, as inferred from fluorescence intensity measurements and XRD patterns. 50/50 CO 2/CH 4 mixed gas permeation measurements reveal stable separation performance up to 1000psia. Ternary mixed gas feeds containing toluene/CO 2/CH 4 and H 2S/CO 2/CH 4 show antiplasticization, but more importantly, selectivity losses due to plasticization did not occur up to 900psia of total feed pressure. These results show that the polyamide-imide family represents a promising class of separation materials for aggressive acid gas purifications. © 2012 Elsevier B.V.

  3. Fast comprehensive two-dimensional gas chromatography method for fatty acid methyl ester separation and quantification using dual ionic liquid columns.

    Science.gov (United States)

    Nosheen, Asia; Mitrevski, Blagoj; Bano, Asghari; Marriott, Philip J

    2013-10-18

    Safflower oil is a complex mixture of C18 saturated and unsaturated fatty acids amongst other fatty acids, and achieving separation between these similar structure components using one dimensional gas chromatography (GC) may be difficult. This investigation aims to obtain improved separation of fatty acid methyl esters in safflower oil, and their quantification using comprehensive two-dimensional GC (GC×GC). Here, GC×GC separation is accomplished by the coupling of two ionic liquid (IL) column phases: the combination of SLB-IL111 with IL59 column phases was finally selected since it provided excellent separation of a FAME standard mixture, as well as fatty acids in safflower and linseed oil, compared to other tested column sets. Safflower oil FAME were well separated in a short run of 16min. FAME validation was demonstrated by method reproducibility, linearity over a range up to 500mgL(-1), and limits of detection which ranged from 1.9mgL(-1) to 5.2mgL(-1) at a split ratio of 20:1. Quantification was carried out using two dilution levels of 200-fold for major components and 20-fold for trace components. The fatty acids C15:0 and C17:0 were not reported previously in safflower oil. The SLB-IL111/IL59 column set proved to be an effective and novel configuration for separation and quantification of vegetable and animal oil fatty acids. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Separating nano graphene oxide from the residual strong-acid filtrate of the modified Hummers method with alkaline solution

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Xuebing, E-mail: xuebinghu2010@gmail.com [Key Laboratory of Inorganic Membrane, Jingdezhen Ceramic Institute, Jingdezhen 333001 (China); Key Laboratory of Inorganic Coating Materials, Shanghai Institute of Ceramics, Chinese Academy of Science, Shanghai 201800 (China); Yu, Yun, E-mail: yunyush@mail.sic.ac.cn [Key Laboratory of Inorganic Coating Materials, Shanghai Institute of Ceramics, Chinese Academy of Science, Shanghai 201800 (China); Wang, Yongqing; Zhou, Jianer [Key Laboratory of Inorganic Membrane, Jingdezhen Ceramic Institute, Jingdezhen 333001 (China); Song, Lixin [Key Laboratory of Inorganic Coating Materials, Shanghai Institute of Ceramics, Chinese Academy of Science, Shanghai 201800 (China)

    2015-02-28

    Graphical abstract: By adding an alkaline (NaOH or KOH) solution, the unprecipitated nano graphene oxide undergoes fast aggregation from the residual strong-acid filtrate of the modified Hummers method and forms the stable floccules when the pH value of the filtrate is about 1.7. The acid–base interaction with the surface functional groups of the carbon layers plays a role in the aggregation of the unprecipitated nano graphene oxide. - Highlights: • The novel and high-efficient method for separating graphene oxide was showed. • Graphene oxide undergoes aggregation and forms the floccules when pH value is ∼1.7. • The acid–base interaction plays a role in the aggregation of graphene oxide. - Abstract: In the modified Hummers method for preparing graphene oxide, the yellow slurry can be obtained. After filtering through a quantitative filter paper, the strong-acid filtrate containing the unprecipitated nano graphene oxide was gained. The corresponding filtrate was added gradually with an alkaline (NaOH or KOH) solution at room temperature. The unprecipitated nano graphene oxide could undergo fast aggregation when the pH value of the filtrate was about 1.7 and formed the stable floccules. X-ray diffraction analysis shows the dominant peak of the floccules is about 11°, which accords to the peak of graphene oxide. Spectra of X-ray photoelectron spectroscopy confirm the presence in the floccules of an abundance of oxygen functional groups and the purified graphene oxide floccules can be obtained. Atomic force microscopy measurement shows the graphene oxide floccules consists of sheet-like objects, mostly containing only a few layers (about 5 layers). Zeta potential analysis demonstrates the surface charge of the graphene oxide is pH-sensitive and its isoelectric point is ∼1.7. The flocculation mechanism of graphene oxide ascribes to the acid–base interaction with the surface functional groups of the carbon layers.

  5. The Influence of Lactic Acid Concentration on the Separation of Light Rare Earth Elements by Continuous Liquid-Liquid Extraction with 2-Ethylhexyl Phosphonic Acid Mono-2-ethylhexyl Ester

    Science.gov (United States)

    de Carvalho Gomes, Rafael; Seruff, Luciana Amaral; Scal, Maira Labanca Waineraich; Vera, Ysrael Marrero

    2018-02-01

    The separation of rare earth elements (REEs) using solvent extraction adding complexing agents appears to be an alternative to saponification of the extractant. We evaluated the effect of lactic acid concentration on didymium (praseodymium and neodymium) and lanthanum extraction with 2-ethylhexyl phosphonic acid mono-2-ethyl hexyl ester [HEH(EHP)] as extractant. First, we investigated in batch experiments the separation of lanthanum (La) and didymium (Pr and Nd) using McCabe-Thiele diagrams to estimate the number of extraction stages when the feed solution was or was not conditioned with lactic acid. Additionally, we conducted continuous liquid-liquid extraction experiments and evaluated the influence of lactic acid concentration on the REE extraction and separation. The tests showed that the extraction percentage of REEs and the separation factor Pr/La increased when the lactic acid concentration increased, but the didymium purity decreased. Lanthanum, praseodymium, and neodymium extraction rate were 23.0, 89.7, and 99.2 pct, respectively, with 1:1 aqueous/organic volume flow rate and feed solution doped with 0.52 mol L-1 lactic acid. The highest didymium purity reached was 92.0 pct with 0.26 mol L-1 lactic acid concentration.

  6. Separation of amino acids and antibiotics by narrow-bore and normal-bore high-performance liquid chromatography with pre-column derivatization.

    Science.gov (United States)

    Fiedler, H P; Plaga, A

    1987-01-16

    The selectivity, efficiency and lifetime of normal- and narrow-bore columns for high-performance liquid chromatography were investigated for the separation and quantification of amino acids and the amino acid-like antibiotics phosphinothricin and phosphinothricylalanylalanine in biological samples. These compounds were determined by an automated pre-column derivatization with o-phthalaldehyde-2-mercaptoethanol reagent and UV detection at 338 nm.

  7. Radium separation through complexation by aqueous crown ethers and ion exchange or solvent extraction

    Energy Technology Data Exchange (ETDEWEB)

    Chiarizia, R.; Dietz, M.L.; Horwitz, E.P. [Argonne National Lab., IL (United States). Chemistry Div.; Burnett, W.C. [Florida State Univ., Tallahassee, FL (United States). Dept. of Oceanography

    1997-11-01

    The effect of three water-soluble, unsubstituted crown ethers (15-crown-5 (15C5), 18-crown-6 (18C6) and 21-crown-7 (21C7)) on the uptake of Ca, Sr, Ba and Ra cations by a sulfonic acid cation exchange resin, and on the extraction of the same cations by xylene solutions of dinonylnaphthalenesulfonic acid (HDNNS) from aqueous hydrochloric acid solutions has been investigated. The crown ethers enhance the sorption of the larger cations by the ion exchange resin, thereby improving the resin selectivity over calcium, a result of a synergistic interaction between the crown ether and the ionic functional groups of the resin. Similarly, the extraction of the larger alkaline earth cations into xylene by HDNNS is strongly synergized by the presence of the crown ethers in the aqueous phase. Promising results for intra-Group IIa cation separations have been obtained using each of the three crown ethers as the aqueous ligands and the sulfonic acid cation exchange resin. Even greater separation factors for the radium-calcium couple have been measured with the crown-ethers and HDNNS solutions in the solvent extraction mode. The application of the uptake and extraction results to the development of radium separation schemes is discussed and a possible flowchart for the determination of {sup 226}Ra/{sup 228}Ra in natural waters is presented.

  8. Spring flood pH decline in northern Sweden: Towards an operational model separating natural acidity from anthropogenic acidification

    Energy Technology Data Exchange (ETDEWEB)

    Laudon, H.

    1999-10-01

    The spring flood is a defining feature of the ecosystem in northern Sweden. In this region, spring flood is an occasion for dramatic hydrochemical changes that profoundly effect the biodiversity of the aquatic ecosystem. Spring flood is also the period most susceptible to anthropogenic acidification. A belief in the anthropogenic component to pH decline during spring flood has been an important factor in spending over half a billion crowns to lime surface waters in Northern Sweden during the last decade. The natural component of episodic pH decline during spring flood, however, has received less attention. The main objective of this work is to present an operational model for separating and quantifying the anthropogenic and natural contributions of episodic acidification during high flow events in Northern Sweden. The key assumptions in this model are that baseflow ANC has not been affected by anthropogenic acidification, that DOC has not changed due to modern land-use practice and that natural dilution during hydrological episodes can be quantified. The limited data requirements of 10-15 stream water samples before and during spring flood make the model suitable for widespread use in environmental monitoring programs. This makes it possible to distinguish trends of human impact as well as natural pH decline in space and time. Modeling results from northern Sweden demonstrate that the natural driving mechanisms of dilution and organic acidity were the dominant factors in the episodic acidification of spring flood in the region. The anthropogenic contribution to spring pH decline was similar in size to the natural contribution in only two of the more than 30 events where this model was applied. Natural factors alone were found to cause pH values below 4.5 in some streams. Anthropogenic sources of acidity can be superimposed on this natural dynamics. In the sites studied, the magnitude of the anthropogenic ANC decline was correlated to the winter deposition of

  9. Extraction, Separation, and Purification of Blueberry Anthocyanin Using Ethyl Alcohol

    Directory of Open Access Journals (Sweden)

    Zhe Gao

    2017-11-01

    Full Text Available Blueberry contains many substances that are important to the human body and can prevent cardiovascular diseases, protect the retina, and soften blood vessels. Anthocyanin, which is extracted from blueberry, can activate the retina, strengthen vision, reduce serum cholesterol, triglyceride and high-density lipoprotein, and protect cell nucleus tissues from radical oxidation; hence, blueberry is of importance to scientists from different countries. In this study, anthocyanin was extracted and separated from blueberry using ethyl alcohol to investigate the effects of factors, such as ethyl alcohol volume ratio on anthocyanin extraction and separation technologies. The extracting solution was then purified using the macroreticular resin purification method to investigate the effects of ethyl alcohol concentration and eluent dosage on anthocyanin extraction during purification. The research results demonstrated that 60 % ethyl alcohol volume fraction, 1 : 10 mass ratio of solid to liquid, and 60 °C ultrasonic temperature were the best conditions for anthocyanin extraction. The best purification conditions were 95 % ethyl alcohol, which had been acidized by 0.3 % hydrochloric acid and 70 ml of eluent. This work provides a reference for the application of ethyl alcohol in anthocyanin extraction.

  10. Separate and Combined Response to UV-B Radiation and Jasmonic Acid on Photosynthesis and Growth Characteristics of Scutellaria baicalensis

    Directory of Open Access Journals (Sweden)

    Jiaxin Quan

    2018-04-01

    Full Text Available The negative effects of enhanced ultraviolet-B (UV-B on plant growth and development have been reported with many species. Considering the ability of jasmonic acid (JA to improve plant stress tolerance, the hypothesis that JA pretreatment could alleviate the adverse effects of UV-B on S. baicalensis was tested in this study with photosynthesis and growth characteristics. The results showed that UV-B or JA alone both induced photosynthesis inhibition and decreased biomass in stems and leaves. However, the photosynthetic reduction caused by increased UV-B was mainly related to the effect of nonstomatal-limitation, while that of JA was a stomatal-limitation effect. JA pretreatment prior to UV-B could remit the photosynthetic inhibition via the recovery of chlorophyll content, stomatal conductance; and intercellular CO2 concentration (especially the maximum electron transport rate increase. Furthermore, the coaction of JA and enhanced UV-B alleviated some disadvantageous effects on the leaf and did not aggravate the growth damage induced by their separate actions.

  11. Separate and Combined Response to UV-B Radiation and Jasmonic Acid on Photosynthesis and Growth Characteristics of Scutellaria baicalensis.

    Science.gov (United States)

    Quan, Jiaxin; Song, Shanshan; Abdulrashid, Kadir; Chai, Yongfu; Yue, Ming; Liu, Xiao

    2018-04-13

    The negative effects of enhanced ultraviolet-B (UV-B) on plant growth and development have been reported with many species. Considering the ability of jasmonic acid (JA) to improve plant stress tolerance, the hypothesis that JA pretreatment could alleviate the adverse effects of UV-B on S. baicalensis was tested in this study with photosynthesis and growth characteristics. The results showed that UV-B or JA alone both induced photosynthesis inhibition and decreased biomass in stems and leaves. However, the photosynthetic reduction caused by increased UV-B was mainly related to the effect of nonstomatal-limitation, while that of JA was a stomatal-limitation effect. JA pretreatment prior to UV-B could remit the photosynthetic inhibition via the recovery of chlorophyll content, stomatal conductance; and intercellular CO₂ concentration (especially the maximum electron transport rate increase). Furthermore, the coaction of JA and enhanced UV-B alleviated some disadvantageous effects on the leaf and did not aggravate the growth damage induced by their separate actions.

  12. Increments to chiral recognition facilitating enantiomer separations of chiral acids, bases, and ampholytes using Cinchona-based zwitterion exchanger chiral stationary phases.

    Science.gov (United States)

    Wernisch, Stefanie; Pell, Reinhard; Lindner, Wolfgang

    2012-07-01

    The intramolecular distances of anion and cation exchanger sites of zwitterionic chiral stationary phases represent potential tuning sites for enantiomer selectivity. In this contribution, we investigate the influence of alkanesulfonic acid chain length and flexibility on enantiomer separations of chiral acids, bases, and amphoteric molecules for six Cinchona alkaloid-based chiral stationary phases in comparison with structurally related anion and cation exchangers. Employing polar-organic elution conditions, we observed an intramolecular counterion effect for acidic analytes which led to reduced retention times but did not impair enantiomer selectivities. Retention of amphoteric analytes is based on simultaneous double ion pairing of their charged functional groups with the acidic and basic sites of the zwitterionic selectors. A chiral center in the vicinity of the strong cation exchanger site is vital for chiral separations of bases. Sterically demanding side chains are beneficial for separations of free amino acids. Enantioseparations of free (un-derivatized) peptides were particularly successful in stationary phases with straight-chain alkanesulfonic acid sites, pointing to a beneficial influence of more flexible moieties. In addition, we observed pseudo-enantiomeric behavior of quinine and quinidine-derived chiral stationary phases facilitating reversal of elution orders for all analytes. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. 35Cl/37Cl isotope effects in 103Rh NMR of [RhCln(H2O)6−n]3−n complex anions in hydrochloric acid solution as a unique ‘NMR finger-print’ for unambiguous speciation

    International Nuclear Information System (INIS)

    Geswindt, Theodor E.; Gerber, Wilhelmus J.; Brand, D. Jacobus; Koch, Klaus R.

    2012-01-01

    Graphical abstract: 35 Cl/ 37 Cl isotope effects in 103 Rh NMR as a unique ‘NMR-fingerprints’ leading to the unambiguous assignment of [RhCl n (H 2 O) 6−n ] 3−n (n = 3–6) complexes without reliance on accurate δ( 103 Rh) chemical shifts. Highlights: ► Direct 103 Rh NMR (19.11 MHz) spectroscopic method of speciation of [RhCl n (H 2 O) 6−n ] 3−n in HCl. ► 35 Cl/ 37 Cl isotope effects in 103 Rh NMR of [RhCl n (H 2 O) 6−n ] 3−n anions isotopologue and isotopomer induced 103 Rh NMR ‘finger-print’ for unambiguous identification. ► 103 Rh NMR identification of stereoisomers without a need for accurate chemical shifts. - Abstract: A detailed analysis of the 35 Cl/ 37 Cl isotope effects observed in the 19.11 MHz 103 Rh NMR resonances of [RhCl n (H 2 O) 6−n ] 3−n complexes (n = 3–6) in acidic solution at 292.1 K, shows that the ‘fine structure’ of each 103 Rh resonance can be understood in terms of the unique isotopologue and in certain instances the isotopomer distribution in each complex. These 35 Cl/ 37 Cl isotope effects in the 103 Rh NMR resonance of the [Rh 35/37 Cl 6 ] 3− species manifest only as a result of the statistically expected 35 Cl/ 37 Cl isotopologues, whereas for the aquated species such as for example [Rh 35/37 Cl 5 (H 2 O)] 2− , cis-[Rh 35/37 Cl 4 (H 2 O) 2 ] − as well as the mer-[Rh 35/37 Cl 3 (H 2 O) 3 ] complexes, additional fine-structure due to the various possible isotopomers within each class of isotopologues, is visible. Of interest is the possibility of the direct identification of stereoisomers cis-[RhCl 4 (H 2 O) 2 ] − , trans-[RhCl 4 (H 2 O) 2 ] − , fac-[RhCl 3 (H 2 O) 3 ] and mer-[RhCl 3 (H 2 O) 3 ] based on the 103 Rh NMR line shape, other than on the basis of their very similar δ( 103 Rh) chemical shift. The 103 Rh NMR resonance structure thus serves as a novel and unique ‘NMR-fingerprint’ leading to the unambiguous assignment of [RhCl n (H 2 O) 6−n ] 3−n complexes (n = 3–6

  14. Radiochemical separation of cadmium-109

    International Nuclear Information System (INIS)

    Egamediev, S.; Mukhtarov, A.; Nurbaeva, D.; Rakhmanov, A.

    2006-01-01

    chlorides with 6 M HCl from nitric acid solutions of Ag, Cu and Cd. Then the solution is filtered to remove silver. The filtrate is evaporated almost to dryness and the solid residue is dissolved in 2 M HCl. The solution obtained is passed through an anion-exchange column with DOWEX 1x8. Cadmium is retained on column at this concentration of HCl while Cu is completely eluted with 30 ml of 2 M HCl. Finally cadmium is eluted with 200 ml of 1 N HNO 3 , while the traces of silver remain on the column. Thus a pure solution of cadmium nitrate is obtained that can be evaporated to the desirable volume. Measuring the activity of the initial and obtained quantity of 109 Cd it is found that 80% of the total cadmium is recovered. Second method is based on the selective adsorption of silver on column containing 0.5 g of polyethenemonosulphide (PEMS or trade name TR-1) from nitric acid solutions of Ag, Cu, Zn and Cd. This sorbent has high adsorptive capacity to silver, its adsorptive capacity reaches to 1920 mg/g from 1.5 M nitric acid solutions. After adsorption of silver the solution obtained evaporated to dryness and the solid residue is dissolved in 0.5 M nitric acid containing 0.1 M hydrobromic acid. Then the solution obtained is percolated through the column, containing 5 ml of Dowex1x8 resin. The copper(II) and zinc are completely eluted with 70 ml of 0.5 M HNO 3 + 0.1 M HBr. The cadmium-109 is eluted with 50 ml of 3 M nitric acid. The obtained solution is evaporated to dryness and the dry residue is treated by evaporation with 2 ml of 12 M hydrochloric acid. After treatment the damp residue is dissolved in 0.1 M hydrochloric acid. The yield of cadmium-109 is higher than 90% and the radiochemical purity was more than 99.9%. These methods will be used for separation and purification of cadmium-109 to make of sealed sources for X-ray fluorescence analysis. The Science and Technologies Center at Cabinet of Ministers of Republic of Uzbekistan support this work (cont ract no.13

  15. Solvent Extraction and Separation of Chromium(III) and (V I) in Aqueous Solutions with Trioctylphosphine Oxide

    International Nuclear Information System (INIS)

    Sekine, T.; Yamada, M.

    1999-01-01

    The solvent extraction of chromium(III) and (V I) in aqueous solutions with a solvating type extractant, trioctylphosphine oxide(TOPO), in hexane is studied. Kinetically inert Cr 3+ is extracted from 1 mol dm -3 sodium perchlorate solution very quickly and quantitatively as Cr(H 2 O · TOPO) 6 3+ (CIO 4 -) 3 . Chromium(V I) in hydrochloric acid is extracted effectively as the H 2 CrO $ (H CI) n centre dot TOPO m species ( m = 2 or 3, n = 0 to 2) and the distribution ratio increased by an increase in the acid concentration. From these, a procedure is proposed for the extraction of both chromium(V I) and chromium(III) in aqueous solution separately with 0.1 mol dm -3 TOPO in hexane

  16. Efficient in situ separation and production of L-lactic acid by Bacillus coagulans using weak basic anion-exchange resin.

    Science.gov (United States)

    Zhang, Yitong; Qian, Zijun; Liu, Peng; Liu, Lei; Zheng, Zhaojuan; Ouyang, Jia

    2018-02-01

    To get rid of the dependence on lactic acid neutralizer, a simple and economical approach for efficient in situ separation and production of L-lactic acid was established by Bacillus coagulans using weak basic anion-exchange resin. During ten tested resins, the 335 weak basic anion-exchange resins demonstrated the highest adsorption capacity and selectivity for lactic acid recovery. The adsorption study of the 335 resins for lactic acid confirmed that it is an efficient adsorbent under fermentation condition. Langmuir models gave a good fit to the equilibrium data at 50 °C and the maximum adsorption capacity for lactic acid by 335 resins was about 402 mg/g. Adsorption kinetic experiments showed that pseudo-second-order kinetics model gave a good fit to the adsorption rate. When it was used for in situ fermentation, the yield of L-lactic acid by B. coagulans CC17 was close to traditional fermentation and still maintained at about 82% even after reuse by ten times. These results indicated that in situ separation and production of L-lactic acid using the 335 resins were efficient and feasible. This process could greatly reduce the dosage of neutralizing agent and potentially be used in industry.

  17. 3D FT-IR imaging spectroscopy of phase-separation in a poly(3-hydroxybutyrate)/poly(L-lactic acid) blend

    Science.gov (United States)

    Miriam Unger; Julia Sedlmair; Heinz W. Siesler; Carol Hirschmugl; Barbara Illman

    2014-01-01

    In the present study, 3D FT-IR spectroscopic imaging measurements were applied to study the phase separation of a poly(3-hydroxybutyrate) (PHB)/poly(L-lactic acid) (PLA) (50:50 wt.%) polymer blend film. While in 2D projection imaging the z-dependent information is overlapped, thereby complicating the analysis, FT-IR spectro-micro-tomography,...

  18. Separation of rare-earth (RE) ions by flotation with the aid of citric acid and hexadecylamine

    International Nuclear Information System (INIS)

    Skrylev, L.D.; Sazonova, V.F.; Pavlenko, S.N.; Karpenko, L.I.

    1989-01-01

    The aim of the present work was to develop further the flotation method for separating RE ions, namely, to examine the possibility of separating Re ions by converting them into citrate complexes and subsequently binding them with the aid of hexadecylamine in difficultly soluble and easily floatable compounds, sublates. Thus, these investigations showed that it is possible in principle to separate RE ions by conversion into citrate complexes followed by flotation separation of the latter from solutions with the aid of hexadecylamine

  19. The Effect of Column and Eluent Fluorination on the Retention and Separation of non-Fluorinated Amino Acids and Proteins by HPLC

    Science.gov (United States)

    Joyner, Katherine; Wang, Weizhen; Yu, Yihua Bruce

    2011-01-01

    The effect of column and eluent fluorination on the retention and separation of non-fluorinated amino acids and proteins in HPLC is investigated. A side-by-side comparison of fluorocarbon column and eluents (F-column and F-eluents) with their hydrocarbon counterparts (H-column and H-eluents) in the separation of a group of 33 analytes, including 30 amino acids and 3 proteins, is conducted. The H-column and the F-column contain the n-C8H17 group and n-C8F17 group, respectively, in their stationary phases. The H-eluents include ethanol (EtOH) and isopropanol (ISP) while the F-eluents include trifluoroethanol (TFE) and hexafluorosopropanol (HFIP). The 2 columns and 4 eluents generated 8 (column, eluent) pairs that produce 264 retention time data points for the 33 analytes. A statistical analysis of the retention time data reveals that although the H-column is better than the F-column in analyte separation and H-eluents are better than F-eluents in analyte retention, the more critical factor is the proper pairing of column with eluent. Among the conditions explored in this project, optimal retention and separation is achieved when the fluorocarbon column is paired with ethanol, even though TFE is the most polar one among the 4 eluents. This result shows fluorocarbon columns have much potential in chromatographic analysis and separation of non-fluorinated amino acids and proteins. PMID:21318121

  20. The adsorption of Tl(I), Au(III), Cu(II) and the separation of 199Tl from alpha bombardment of gold target with PDB-18C6

    International Nuclear Information System (INIS)

    Zhou Dehai; Zhou Jimeng

    1989-01-01

    The adsorptive behavior of polymer of methyl aldehyde of dibenzo-18-crown-6 (PDB-18C6) in hydrochloric acid medium is studied and it is shown that the adsorption of T1(I), Au(III), and Cu(II) depends on the particle size of the crown ether resins, hydrochloric acid concentration and amount of the crown ether resins used. The difference in the adsorption behavior of different particle sizes of crown ether resins may be used for separating Tl(I), Au(III), and Cu(II) ions. The best eluant of Tl(I) and Au(III) is 0.4 mol/l perchloric acid and 2-ethoxy-ethanol. The recovery for Tl(I) is 82-98.8%. The gold target is bombarded in a 1.2 m cyclotron with 25-27 MeV α-particle with a cumulative beam intensities of 27μA·h, and 199 Tl is separated from the gold target with PDB-18C6. γ-spectrometry has shown that the Tl obtained is 199 Tl of high purity containing only about 0.50% 200 Tl

  1. Solvent extraction of platinum with thiobenzanilide. Separation of platinum from copper

    International Nuclear Information System (INIS)

    Shkil', A.N.; Zolotov, Yu.A.

    1989-01-01

    The solvent extraction of micro concentrations of platinum has been investigated from hydrochloric acid media using thiobenzanilide in the presence of SnCl 2 and KI. In the presence of SnCl 2 platinum is extracted rapidly and to significant completion. Conditions have been developed for the quantitative extraction of platinum. The authors have also examined the solvent extraction of copper(II) using thiobenzanilide, interference due to copper(II) and iron(III) on solvent extraction of platinum, and methods to suppress this interference. A procedure has also been developed for the separation of platinum from copper. Solvent extraction of metals was studied using radioactive isotopes: 197 Pt, 64 Cu, 59 Fe, 198 Au, 109 Pd, 110m Ag

  2. Solubility and phase separation of 4-morpholinepropanesulfonic acid (MOPS), and 3-morpholino-2-hydroxypropanesulfonic acid (MOPSO) in aqueous 1,4-dioxane and ethanol solutions

    International Nuclear Information System (INIS)

    Taha, Mohamed; Lee, Ming-Jer

    2011-01-01

    Highlights: → Solubilities of MOPS and MOPSO buffers in aqueous 1,4-dioxane and ethanol solutions. → We found that MOPS-induced phase separation of aqueous solution of 1,4-dioxane. → The phase diagram of (MOPS + water + 1,4-dioxane) system at 298.15 K is documented. → The tie-lines within the two-liquid phase region were also determined at 298.15 K. → The effective excluded volume theory was applied to correlate the binodal LLE data. - Abstract: The buffers 4-morpholinepropanesulfonic acid (MOPS) and 3-morpholino-2-hydroxypropanesulfonic acid (MOPSO) are useful biological zwitterionic buffers within the pH range of 6.5 to 7.9 and 6.2 to 7.6, respectively. The solubilities of these buffers were determined in binary mixtures (1,4-dioxane + water) and (ethanol + water) at T = 298.15 K by using the results of density measurements. It has been observed that MOPS induced liquid-liquid phase splitting for the mixtures of 40% to 90% (w/w) 1,4-dioxane in water. The two-liquid phase formation was visualized with disperse orange 25. The phase equilibrium boundaries, including the regions of one liquid, two liquids, (one liquid + one solid) and (two liquids + one solid), for the (MOPS + water + 1,4-dioxane) system have been determined experimentally at T = 298.15 K. The tie lines of the (liquid + liquid) equilibrium were also measured. The Othmer-Tobias and Bancroft equation were used to evaluate the reliability of the tie-line data. The binodal curve was fitted to an empirical equation and the effective excluded volume (EEV) model. The apparent free energies of transfer (ΔG tr ' ) of MOPS and MOPSO from water to 1,4-dioxane and ethanol solutions have been calculated from the solubility data. These ΔG tr ' values were compared with those of some related biological buffers (TRIS, TAPS, TAPSO, and TABS). Furthermore, we also calculated the contribution of transfer free energies (Δg tr ' ) of -OH group from water to 1,4-dioxane and ethanol solutions.

  3. Chelating ion exchange with macroreticular hydroxamic acid resins

    International Nuclear Information System (INIS)

    Phillips, R.J.

    1980-01-01

    The synthesis, reactions, and analytical applications of hydroxamic acids, including chelating resins with this functional group, are reviewed. A procedure for attaching N-phenyl hydroxamic acid groups to Amberlite XAD-4 is described. The extraction of 20 metal ions from 2 M hydrochloric acid by this resin is discussed. Conditions for the quantitative extraction and back-extraction of 9 ions are reported. Results are compared with work on solvent extraction with N-phenylbenzohydroxamic acid. Procedures for attaching N-methyl and N-unsubstituted hydroxamic acid groups to Amberlite XAD-4 are described. The N-phenyl, N-methyl, and N-unsubstituted hydroxamic acid resins are compared with respect to metal-ion complexation. The scope of applications for hydroxamic acid resins is investigated by studying the extraction of 19 metal ions as a function of pH. The resins are especially suitable for the extraction of zirconium(IV), titanium(IV), and uranium(IV) from strongly acidic solution. Aluminum(III) is separated from calcium and phosphate by extraction at pH 4. The use of the resins for the purification of reagents, concentration of trace constituents, and chromatographic separation is demonstrated

  4. Corrosion Behavior of Ni3(Si,Ti in Hydrochloric Acid Solution

    Directory of Open Access Journals (Sweden)

    Gadang Priyotomo

    2013-06-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The corrosion behaviour of the intermetallic compounds Ni3(Si,Ti (L12: single phase, has been investigated using an immersion test, electrochemical method, scanning electron microscope in 0.5 kmol/m3 HCl at 303 K. In addition, the corrosion behaviour of austenitic stainless steel type 304 and C276 was studied under the same experimental conditions as references. It was found that the intergranular attack was observed for Ni3(Si,Ti in the immersion test. From the immersion test and polarization curves, Ni3(Si,Ti had the moderate corrosion resistance, while the corrosion resistances of C 276 and type 304 were the highest and the lowest. Ni3(Si,Ti and type 304 were difficult to form a stable passive film, but not for C276. A further experiment must be conducted to clarify the stability of film for Ni3(Si,Ti in detail.

  5. Determination of Sn{sup 2+} in lyophilized radiopharmaceuticals by voltammetry, using hydrochloric acid as electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Dadda, Adilio S.; Teixeira, Ariane C.; Feltes, Paula K.; Campos, Maria M.; Moriguchi-Jeckel, Cristina M., E-mail: adiliosd@yahoo.com.br [Pontifícia Universidade Católica do Rio Grande do Sul (PUC-RS), Porto Alegre-RS (Brazil); Leite, Carlos E. [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre-RS (Brazil)

    2014-07-01

    This work aimed to develop and validate a routine method for the specific determination of Sn{sup 2+} 2-methoxy isobutyl isonitrile (MIBI) radiopharmaceutical kits. A voltammetric electrochemical technique was used for the analysis. Screening experiments revealed that 1 mol L{sup -1} HCl electrolyte showed the best results, among all the tested solutions. Stability experiments showed a gradual decline in the current of MIBI, and 23 days after the preparation of the solution, the current corresponding to stannous ion disappeared. To confirm the selectivity of the technique using HCl, we have induced oxidation of SnCl{sub 2} that resulted in a proportional decline of the current in the voltammogram. The reliability of the method was observed with the values of precision and accuracy intra- and inter-assay, and also its robustness. We provide novel evidence on the selective detection of Sn{sup 2+} in the presence of its oxidized form in radiopharmaceutical kits, by using 1 mol L{sup -1} HCl as electrolyte. (author)

  6. Behaviour of Tiu-Nb-Ni alloys in sulfuric and hydrochloric acids

    International Nuclear Information System (INIS)

    Shcherbakov, A.I.; Dorofeeva, V.N.; Tomashov, N.D.; Goncharenko, B.A.; Mikheev, V.S.

    1991-01-01

    Regularities of corrosion behaviour and passivation of ternary alloys containing 0.2; 0.5, 1,2, 3% Ni and 1,2,3,4,5,6,8 % Nb in 5n. H 2 SO 4 and 5n HCl, i.e. under conditions when unalloyed titanium dissolves actively, are considered. High cathodic efficiency of nickel plays essential role for the ternary alloy transfer to passive state, while a lower cathodic efficiency of niobium is sufficient for the alloy maintaining in the passive state. At the same time high corrosion resistance of niobium (in contract to nickel) undr potentials of titanium passive state promotes stable maintenance of the alloy in the passive state

  7. Blue tetrazolium as a novel corrosion inhibitor for cold rolled steel in hydrochloric acid solution

    International Nuclear Information System (INIS)

    Li Xianghong; Deng Shuduan; Fu Hui

    2010-01-01

    The inhibition effect of blue tetrazolium (BT) on the corrosion of cold rolled steel (CRS) in 1.0 M HCl solution at 20 o C was investigated by weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM) methods. The results show that BT is a very good inhibitor, and the adsorption of BT on CRS surface obeys Langmuir adsorption isotherm. Polarization curves reveal that BT acts as a mixed-type inhibitor. EIS spectra exhibit one capacitive loop and confirm the inhibitive ability. The inhibition action of BT is also evidenced by SEM images.

  8. HYDROLYSIS OF MTBE TO TBA IN GROUND WATER SAMPLES WITH HYDROCHLORIC ACID

    Science.gov (United States)

    Conventional sampling and analytical protocols have poor sensitivity for fuel oxygenates that are alcohols, such as tert-butyl alcohol (TBA). Because alcohols are miscible or highly soluble in water, alcohols are not efficiently transferred to the gas chromatograph for analysis....

  9. Electrochemical Study on Newly Synthesized Chlorocurcumin as an Inhibitor for Mild Steel Corrosion in Hydrochloric Acid

    Directory of Open Access Journals (Sweden)

    Ahmed A. Al-Amiery

    2013-11-01

    Full Text Available A new curcumin derivative, i.e., (1E,4Z,6E-5-chloro-1,7-bis(4-hydroxy-3-methoxyphenylhepta-1,4,6-trien-3-one (chlorocurcumin, was prepared starting with the natural compound curcumin. The newly synthesized compound was characterized by elemental analysis and spectral studies (IR, 1H-NMR and 13C-NMR. The corrosion inhibition of mild steel in 1 M HCl by chlorocurcumin has been studied using potentiodynamic polarization (PDP measurements and electrochemical impedance spectroscopy (EIS. The inhibition efficiency increases with the concentration of the inhibitor but decreases with increases in temperature. The potentiodynamic polarization reveals that chlorocurcumin is a mixed-type inhibitor. The kinetic parameters for mild steel corrosion were determined and discussed.

  10. Anticoccidial activity of hydrochloric acid (HCl against Eimeria tenella in broiler chickens

    Directory of Open Access Journals (Sweden)

    Rao Z Abbas

    2011-05-01

    Full Text Available The present study was planned to evaluate the anticoccidial activity of the different concentrations of the HCl against Eimeria tenella infection in broiler chickens in comparison with the amprolium anticoccidial. For this purpose, a total of 198 chicks were placed 11 per pen with three pens per treatment. The different concentrations of HCl (1000ppm, 2000ppm and 3000ppm and amproilum (at the dose rate of 125ppm were given to the experimental groups in drinking water from 10 to 19th days of age. One group was kept as infected non medicated control and one as non infected non medicated control. At the 12th day of age, all the groups were inoculated orally with 75,000 sporulated oocysts except non infected non medicated control. Anticoccidial activity was evaluated on the basis of performance (weight gain, feed conversion ratio and pathogenic (oocyst score, lesion score and mortality %age parameters. Among HCl medicated groups, the maximum anticoccidial effect was seen in the group medicated with 1000ppm HCl followed by 2000ppm and 3000ppm HCl medicated groups. Amprolium and 1000ppm HCl were almost equivalent in suppressing the negative performance and pathogenic effects associated with coccidiosis (Eimeria tenella challenge. In summary, the lower doses of HCl have the potential to be used as alternative to chemotherapeutic drugs for Eimeria tenella control. It is therefore suggested that further studies should be carried out to determine the possible minimum safe levels of HCl with least toxic effects to be used as anticoccidial.

  11. Effect of some pyrimidinic Schiff bases on the corrosion of mild steel in hydrochloric acid solution

    International Nuclear Information System (INIS)

    Ashassi-Sorkhabi, H.; Shaabani, B.; Seifzadeh, D.

    2005-01-01

    The efficiency of benzylidene-pyrimidin-2-yl-amine (A) (4-methyl-benzylidene)-pyrimidine-2-yl-amine (B) and (4-chloro-benzylidene)-pyrimidine-2-yl-amine, as corrosion inhibitors for mild steel in 1 M HCl have been determined by weight loss measurements and electrochemical polarization method. The results showed that these inhibitors revealed a good corrosion inhibition even at very low concentrations. Polarization curves indicate that all compounds are mixed type inhibitors. The effect of various parameters such as temperature and inhibitor concentration on the efficiency of the inhibitors has been studied. Activation energies of corrosion reaction in the presence and absence of inhibitors have been calculated. The adsorption of used compounds on the steel surface obeys Langmuir's isotherm. It appears that an efficient inhibition is characterized by a relatively greater decrease in free energy of adsorption. Significant correlations are obtained between inhibition efficiency and quantum chemical parameters using quantitative structure-activity relationship (QSAR) method

  12. Adsorption and inhibitive properties of sildenafil (Viagra) for zinc in hydrochloric acid solution

    Science.gov (United States)

    Fouda, A. S.; Ibrahim, H.; Atef, M.

    Sildenafil (Viagra) was investigated as corrosion inhibitor for Zn in 1 M HCl solution using chemical and electrochemical methods at 25 °C. Electrochemical results showed that this drug is efficient inhibitor for Zn in HCl and the inhibition efficiency (IE) reached to 91% at 300 ppm. The IE increases with the drug concentration and decreases with increasing temperature. The adsorption of this drug on Zn surface follows Langmuir adsorption isotherm. The polarization plots revealed that Sildenafil acts as a mixed-type inhibitor. The thermodynamic parameters of activation and adsorption were calculated and discussed. The surface morphology of the Zn specimens was evaluated using scanning electron microscope (SEM), energy dispersive X-ray (EDX), atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR) techniques.

  13. Adsorption and inhibitive properties of sildenafil (Viagra for zinc in hydrochloric acid solution

    Directory of Open Access Journals (Sweden)

    A.S. Fouda

    Full Text Available Sildenafil (Viagra was investigated as corrosion inhibitor for Zn in 1 M HCl solution using chemical and electrochemical methods at 25 °C. Electrochemical results showed that this drug is efficient inhibitor for Zn in HCl and the inhibition efficiency (IE reached to 91% at 300 ppm. The IE increases with the drug concentration and decreases with increasing temperature. The adsorption of this drug on Zn surface follows Langmuir adsorption isotherm. The polarization plots revealed that Sildenafil acts as a mixed-type inhibitor. The thermodynamic parameters of activation and adsorption were calculated and discussed. The surface morphology of the Zn specimens was evaluated using scanning electron microscope (SEM, energy dispersive X-ray (EDX, atomic force microscopy (AFM and Fourier transform infrared spectroscopy (FTIR techniques. Keywords: Zn, Corrosion inhibition, HCl, SEM, EDX, AFM, FTIR, Sildenafil drug

  14. A novel imidazoline derivative as corrosion inhibitor for P110 carbon steel in hydrochloric acid environment

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    2015-09-01

    Full Text Available A novel imidazoline derivative, 2-methyl-4-phenyl-1-tosyl-4, 5-dihydro-1H-imidazole (IMI, was prepared and investigated as corrosion inhibitor for P110 carbon steel in 1.0 M HCl solution by weight loss measurements, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS tests. The inhibition efficiency increased with the rising concentration of IMI inhibitor. The test results and fitting data indicated that the IMI behaved as a mixed-type inhibitor and obeys the Langmuir adsorption isotherm. Scanning electron microscopy (SEM was carried out to investigate the surface of carbon steel specimens, showing great protection from aggressive solution. Finally, inhibition mechanism of IMI on metal surface was further discussed.

  15. Inhibition of Mild Steel Corrosion in Hydrochloric Acid Solution by New Coumarin

    Directory of Open Access Journals (Sweden)

    Abdul Amir H. Kadhum

    2014-06-01

    Full Text Available A new coumarin derivative, N,N′-((2E,2′E-2,2′-(1,4-phenylenebis (methanylylidenebis(hydrazinecarbonothioylbis(2-oxo-2H-chromene-3-carboxamide PMBH, was synthesized and its chemical structure was elucidated and confirmed using spectroscopic techniques (Infrared spectroscopy IR, Proton nuclear  magnetic resonance, 1H-NMR and carbon-13 nuclear magnetic resonance 13C-NMR. The corrosion inhibition effect of PMBH on mild steel in 1.0 M HCl was investigated using corrosion potential (ECORR, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS, and electrochemical frequency modulation (EFM measurements. The obtained results indicated that PMBH has promising inhibitive effects on the corrosion of mild steel in 1.0 M HCl across all of the conditions examined. Scanning electron microscopy (SEM was used to investigate the morphology of the mild steel before and after immersion in 1.0 M HCl solution containing 0.5 mM of PMBH. Surface analysis revealed improvement of corrosion resistance in presence of PMBH.

  16. Inhibition of Mild Steel Corrosion in Hydrochloric Acid Solution by New Coumarin

    Science.gov (United States)

    Kadhum, Abdul Amir H.; Mohamad, Abu Bakar; Hammed, Leiqaa A.; Al-Amiery, Ahmed A.; San, Ng Hooi; Musa, Ahmed Y.

    2014-01-01

    A new coumarin derivative, N,N′-((2E,2′E)-2,2′-(1,4-phenylenebis(methanylylidene))bis(hydrazinecarbonothioyl))bis(2-oxo-2H-chromene-3-carboxamide) PMBH, was synthesized and its chemical structure was elucidated and confirmed using spectroscopic techniques (Infrared spectroscopy IR, Proton nuclear magnetic resonance, 1H-NMR and carbon-13 nuclear magnetic resonance 13C-NMR). The corrosion inhibition effect of PMBH on mild steel in 1.0 M HCl was investigated using corrosion potential (ECORR), potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and electrochemical frequency modulation (EFM) measurements. The obtained results indicated that PMBH has promising inhibitive effects on the corrosion of mild steel in 1.0 M HCl across all of the conditions examined. Scanning electron microscopy (SEM) was used to investigate the morphology of the mild steel before and after immersion in 1.0 M HCl solution containing 0.5 mM of PMBH. Surface analysis revealed improvement of corrosion resistance in presence of PMBH. PMID:28788680

  17. Electrochemical Study on Newly Synthesized Chlorocurcumin as an Inhibitor for Mild Steel Corrosion in Hydrochloric Acid

    Science.gov (United States)

    Al-Amiery, Ahmed A.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar; Musa, Ahmed Y.; Li, Cheong Jiun

    2013-01-01

    A new curcumin derivative, i.e., (1E,4Z,6E)-5-chloro-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,4,6-trien-3-one (chlorocurcumin), was prepared starting with the natural compound curcumin. The newly synthesized compound was characterized by elemental analysis and spectral studies (IR, 1H-NMR and 13C-NMR). The corrosion inhibition of mild steel in 1 M HCl by chlorocurcumin has been studied using potentiodynamic polarization (PDP) measurements and electrochemical impedance spectroscopy (EIS). The inhibition efficiency increases with the concentration of the inhibitor but decreases with increases in temperature. The potentiodynamic polarization reveals that chlorocurcumin is a mixed-type inhibitor. The kinetic parameters for mild steel corrosion were determined and discussed. PMID:28788402

  18. Influence of the hydrolysis conditions on the properties of tellurium coatings obtained from hydrochloric acid baths

    International Nuclear Information System (INIS)

    Bigelis, V.M.; Kim, G.N.; Navalikhin, L.V.; Kalanov, M.; Abrarov, O.A.

    1982-01-01

    The structure of tellurium coatings has been studied using the methods of activational analysis on fast neutrons, roentgenography using DRON-2. The study is carried out in electrolyte 1N TeO 2 +6NHCl+2NH 2 SO 4 at the temperatures 25 and 95 deg C in the range of current densities 10-150 mA/cm 2 with and without mixing. Atomic content of chlorine and oxygen in deposite depending on the electrolyte work is determined. Nicrohardness, density, specific resistance of the coatings investigated are determined

  19. The inhibitive action of sodium castor sulphonate Towards the corrosion of aluminium in Hydrochloric acid

    OpenAIRE

    Soliman, S.A.; Mourad, M. Y.

    1993-01-01

    The dissolution of aluminium in 2M HC1 solution in presence of sodium castor sulphonate (SCS) has been studied using thermometric and hydrogen evolution methods. The results showed that the additive retards the dissolution due to its chemisorption on the metal surface via 71 the electrons of the double bond. The inhibition obyes the Frumkin's isotherm. تمت دراسة ذوبان فلز الألمنيوم في محلول 2 مولاري من حمض الهيدروكلوريك في وجود سلفونات الخروع الصوديومية باستخدام الطريقة الحرارية وطريقة تص...

  20. Thermometric Study of Inhibition of Aluminium Corrosion in Hydrochloric Acid Solution

    OpenAIRE

    Al Gaber, A.S. [امينة سلطان الجابر; Seliman, S. A.; Mourad, M.

    1997-01-01

    The use of 6- amino - 4- (4-phenyl)-l,4- dihydro -3- methylpyrano [2,3- c] pyrazole -5- carbonitrile and some related compounds as corrosion inhibitors for aluminium in 2 M HCl solution was studied by the thermometric method. The results indicate that the additives reduce the corrosion rate via weak adsorption through the cationic oxygen of the pyran ring. They act as mixed inhibitors and their adsorption was found to obey Frumkin's isotherm. The inhibition efficiency of the additives is rela...

  1. In-situ polymerized polyaniline films. Preparation in solutions of hydrochloric, sulfuric, or phosphoric acid

    Czech Academy of Sciences Publication Activity Database

    Šeděnková, Ivana; Trchová, Miroslava; Blinova, Natalia V.; Stejskal, Jaroslav

    2006-01-01

    Roč. 515, č. 4 (2006), s. 1640-1646 ISSN 0040-6090 R&D Projects: GA AV ČR IAA4050313; GA AV ČR IAA400500504 Institutional research plan: CEZ:AV0Z40500505 Keywords : polyaniline * conducting polymer * thin films Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.666, year: 2006

  2. Identification of candidate amino acids involved in the formation of pink-red pigments in onion (Allium cepa L.) juice and separation by HPLC.

    Science.gov (United States)

    Lee, Eun Jin; Yoo, Kil Sun; Patil, Bhimanagouda S

    2010-10-01

    The formation of pink-red pigments ("pinking") by various amino acids was investigated by reacting amino acids with compounds present in onion juice. The unknown pink-red pigments were generated and separated using high-performance liquid chromatography (HPLC) and a diode array detector (DAD) in the range of 200 to 700 nm. To generate pink-red pigments, we developed several reaction systems using garlic alliinase, purified 1-propenyl-L-cysteine sulfoxide (1-PeCSO), onion thiosulfinate, natural onion juice, and 21 free amino acids. The compound 1-PeCSO was a key compound associated with pinking in the presence of both the alliinase and amino acids. Numerous naturally occurring pink-red pigments were detected and separated from pink onion juice using the HPLC-DAD system at 515 nm. Most free amino acids, with the exceptions of histidine, serine, and cysteine, formed various pink-red pigments when reacted with onion thiosulfinate. This observation indicated that onion pinking is caused not by a single pigment, but by many. Furthermore, more than one color compound could be produced from a single amino acid; this explains, in part, why there were many pink-red compound peaks in the chromatogram of discolored natural onion juice. We presumed that the complexity of the pink-red pigments was due to the involvement of more than 21 natural amino acids as well as several derivatives of the color products produced from each amino acid. We observed that the pinking process in onion juice is very similar to that of the greening process in crushed garlic, emphasizing that both thiosulfinate from flavor precursors and free amino acids are absolutely required for the discoloration.

  3. Interaction of magnesium diboride with HΛ2O, HΛ2OΛ2 and with acids

    International Nuclear Information System (INIS)

    Lyashenko, V.I.; Kosolapova, T.Ya.; Serebryakova, T.I.

    1985-01-01

    Chemical stability of magnesium diboride in some agressive media is investigated. It is shown that magnesium diboride possesses high chemical activity in relation to acids (nitric, phosphoric, hydrochloric, sulphuric). The fluohydric acid and hydrogen peroxide completely decompose magnesium boride. The kinetics of MgB 2 decomposition in aqueous solutions of acids (hydrochloric, sulphuric, nitric) and in water is studied. Activation energies and solubility rate constants are calculated

  4. Effect of acid- and alkaline-aided extractions on functional and rheological properties of proteins recovered from mechanically separated turkey meat (MSTM).

    Science.gov (United States)

    Hrynets, Yuliya; Omana, Dileep A; Xu, Yan; Betti, Mirko

    2010-09-01

    Functional and rheological characteristics of acid- and alkali-extracted proteins from mechanically separated turkey meat (MSTM) have been investigated. Extractions were carried out at 4 pH values (2.5, 3.5, 10.5, and 11.5). The study demonstrated that alkali and acid extractions resulted in significant (P hardness, chewiness, springiness, and cohesiveness) of recovered proteins were found to be unaffected (P > 0.05) by different extraction pH. The protein extracted at pH 3.5 formed a highly viscoelastic gel network as evidenced by storage modulus (G') values, whereas the gel formed from proteins extracted at pH 10.5 was found to be the weakest. The work also revealed that acid treatments were more effective for removal of total heme pigments from MSTM. Color characteristics of protein isolates were markedly improved compared to the initial material and tended to be better when subjected to acid extractions. Mechanically separated meat is one of the cheapest sources of protein obtained by grinding meat and bones together and forcing the mixture through a perforated drum. The use of mechanically separated turkey meat (MSTM) for the production of further processed poultry products is limited due to its undesirable color and textural properties. Recovery of proteins from MSTM using pH shifting process will help the poultry processors to get better returns and also create opportunity to produce functional food ingredients.

  5. Separation of polyunsaturated fatty acid esters by flowing liquid membrane with porous partition.; Kakumaku gata ryudo ekimaku ni yoru kodo fuhowa shibosan esuteru no bunri

    Energy Technology Data Exchange (ETDEWEB)

    Yokosawa, R.; Nii, S.; Takahashi, K. [Nagoya Univ., Nagoya (Japan). Depertment of Chemical Engineering; Misawa, Y. [Harima Chemicals, Inc., Osaka (Japan)

    2000-07-10

    A laboratory-constructed flowing liquid membrane apparatus with porous partition (FLM) was applied to the separation of such polyunsaturated fatty acid esters (PUFA-Ets) as eicosapentaenoic acid ethylester (EPA-Et) and docosahexaenoic acid ethylester (DHA-Et) at 293 K. The hydrophilic porous membrane was used as a partition, and 2 M AgNO{sub 3} aqueous solution was used as a membrane liquid. By using dodecane as a feed diluent and m-xylene as a recovery solution, PUFA-Ets were successfully separated from mixture of fatty acid esters. The recovery fraction of PUFA-Ets and the separation degree between DHA-Et and EPA-Et were investigated ; it increases with the velocity of membrane liquid and the flow path length in the module, while it decreased with the velocity of feed and recovery solution. The recovery fraction of DHA-Et reachs 60% with only 8 s-retention time by the continuous operation. The concentrations of the DHA-Et at the outlet of the module were simulated based on the mass transfer model, which gave nearly 85% recovery fraction with 30 s-retention time. These results show that a stable operation, a high recovery and a high recovery and a high throughput are realized by the FLM. (author)

  6. Design and synthesis of some polyaminopolycarboxylic acids and the structural influence of their anions on the separation of actinides and lanthanides

    International Nuclear Information System (INIS)

    Tse, P.K.

    1983-01-01

    Investigation of some methods for the preparation of four polyaminopolycarboxylic acids: thiobis(ethylenenitrilo)-N,N,N',N'-tetraacetic acid, N,N-bis(2-aminoethyl)aniline-N',N',N'',N''-tetraacetic acid, bis(3-aminopropyl)ether-N,N,N',N'-tetraacetic acid and N,N-bis[N',N'-dicarboxymethyl-3-aminopropyl]-N-methylammonioacetate are reported. The coordinating properties of their anions with regard to lanthanide ions have been examined. Polyaminopolycarboxylates form 1:1 chelate species with trivalent lanthanide ions in aqueous media. The stability constants of their metal chelate species depend upon the size of the chelating rings formed, the basicity of the middle atom in the chain, and the number of coordination points between anion and metal cation. Tracer level 241 Am- 155 Eu cation-exchange experiments explore how the relative magnitude of the chelate stability constants affects the separation of members of the lanthanide and actinide series

  7. Separative recovery with lime of phosphate and fluoride from an acidic effluent containing H3PO4, HF and/or H2SiF6.

    Science.gov (United States)

    Gouider, Mbarka; Feki, Mongi; Sayadi, Sami

    2009-10-30

    Fluoride content and flow-rate of fertilizer plant wastewater from phosphoric acid and/or triple superphosphate (TSP) production lead to the discharge of several thousand tons of fluoride (F(-)) per year and even more for phosphate (PO4(3-)). Since sustainability is an important environmental concern, the removal methods should allow phosphorus and fluoride to be recycled as a sustainable products for use as raw materials either in agricultural or industrial applications. In the present work, separative recovery with lime of these two target species was investigated. A preliminary speciation study, carried out on the crude effluent, showed that two forms of fluoride: HF and H2SiF6 are present in a highly acidic medium (pH approximately 2). Evidence that fluoride is present under both free (HF) and combined (H2SiF6) forms, in the phosphate-containing effluent, was provided by comparing potentiometric titration curves of a crude wastewater sample and synthetic acid mixtures containing H3PO4, HF and H2SiF6. In a second step synthetic effluent containing mixtures of the following acids: HF, H2SiF6 and H3PO4, were treated with lime. The behaviour of these compounds under lime treatment was analysed. The data showed that fluoride has a beneficial effect on phosphate removal. Moreover, by acting on the precipitation pH, a "selective" recovery of fluoride and phosphate ions was possible either from phosphoric acid/hydrofluoric acid or phosphoric acid/hexafluorosilicic acid mixtures. Indeed, the first stage of the separative recovery, led to a fluoride removal efficiency of 97-98% from phosphoric acid/hydrofluoric acid mixture. It was of 93-95% from phosphoric acid/hexafluorosilicic acid mixture. During the second stage, the phosphate precipitation reached 99.8% from both acidic mixtures whereas it did not exceed 82% from a solution containing H3PO4 alone. The XRD and IR analyses showed that during lime treatment, a H2SiF6 hydrolysis occurred, instead of CaSiF6 solid

  8. Trans-fatty acid consumption and heart rate variability in two separate cohorts of older and younger adults

    Science.gov (United States)

    Soares-Miranda, Luisa; Stein, Phyllis K; Imamura, Fumiaki; Sattelmair, Jacob; Lemaitre, Rozenn N; Siscovick, David S; Mota, Jorge; Mozaffarian, Dariush

    2014-01-01

    Background Trans-fatty acid (TFA) consumption is associated with risk of coronary heart disease, and trans-18:2, but not trans-18:1, in red blood cells membranes has been associated with sudden cardiac arrest. Abnormal heart rate variability (HRV) reflects autonomic dysfunction and predicts cardiac death. Relationships between TFA consumption and HRV remain under-studied. We determined whether total TFA consumption, as well as trans-18:1 and trans-18:2 TFA consumption, were independently associated with HRV in two independent cohorts in the US and Portugal. Methods and Results In two independent cohorts of older US adults (Cardiovascular Health Study ([CHS], age=72±5yrs, 1989/1995) and young Portuguese adults (Porto, age=19±2yrs, 2008/2010), we assessed habitual TFA intake by food frequency questionnaires in CHS (separately estimating trans-18:1 and trans-18:2) and multiple 24-hour recalls in Porto (estimating total TFA only, which in a subset correlated with circulating trans-18:2, but not trans-18:1, suggesting that we captured the former). HRV was assessed using 24-hour Holters in CHS (N=1,076) and repeated short-term (5-min) ECGs in Porto (N=160). We used multivariate-adjusted linear regression to relate TFA consumption to HRV cross-sectionally (CHS, Porto) and longitudinally (CHS). In CHS, higher trans-18:2 consumption was associated with lower 24-hour standard-deviation-of-all-normal-to-normal-intervals (SDNN) both cross-sectionally (−12%, 95%CI=6–19%, p=0.001) and longitudinally (−15%, 95%CI=4–25 %, p= 0.009), and lower 24-hour SDANN and SDNN-index (pHRV, in particular time-domain indices (SDNN, SDANN, SDNN-index; pHRV in both older and young adults. Trans-18:1 consumption is associated with more favorable HRV indices in older adults. Our results support the need to investigate potential HRV related mechanisms whereby trans-18:2 may increase arrhythmic risk. PMID:22772898

  9. GC separation of amino acid enantiomers via derivatization with heptafluorobutyl chloroformate and Chirasil-L-Val column

    Czech Academy of Sciences Publication Activity Database

    Zahradníčková, Helena; Hušek, Petr; Šimek, Petr

    2009-01-01

    Roč. 32, č. 22 (2009), s. 3919-3924 ISSN 1615-9306 R&D Projects: GA ČR GA203/09/2014 Institutional research plan: CEZ:AV0Z50070508 Keywords : chiral separation * derivatization * D,L-AAs Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.551, year: 2009

  10. Separation of americium and neodymium by selective stripping and subsequent extraction with HDEHP using DTPA-lactic acid solution in a closed loop

    International Nuclear Information System (INIS)

    Svantesson, I.; Hangstroem, I.; Persson, G.; Liljenzin, J.O.

    1979-01-01

    A method for the separation of trivalent actinides and lanthanides is proposed. The method is based on selective stripping of the actinides from 1M HDEHP into an aqueous phase containing ammonia, DTPA and lactic acid followed by subsequent extraction into a second organic phase also containing 1M HDEHP. The aqueous phase is recycled in a closed loop, thereby reducing the amounts of secondary waste. Distribution ratios for Am and Nd have been measured at varying DTPA and lactic acid concentrations and at varying pH. The distribution of ammonia was also measured. (author)

  11. Rirang uranium ore processing : separation of rare earth from alkaline digest

    International Nuclear Information System (INIS)

    Erni, R.A.; Pudjianto, R.; Zahardi; Susilaningtyas

    2000-01-01

    Rirang uranium ore contains several economically potential elements, including U (0.52%), RE (63.04 %), PO 4 3- 24.55 % and Th 0.02 %. Separation and purification processes are employed to obtain relatively pure concentrate of the elements. Separation of phosphate by decomposition using NaOH was conducted previously. The present experiment has an objective, e.g. to separate RE from U and Th through a two step process, total dissolution of RE, U, Th and undercomposed of phosphate remain using HCI, by precipitation of U and Th using NH 4 OH. Experimental condition includes dissolution of RE in hydrochloric acid 15 ml/10 gr feed at 80 o C for 1 hr, followed by precipitation of U and Th using 2 N NH 4 OH at pH 6.4 and room temperature. Experimental data show excellent dissolution recovery for Re 94.41 %, U 99.15 %, Th 95.17 %, while precipitation of U and Th produced separation recovery of RE 91.97 %, U 1.01 %, Th 5 % and PO 4 3- not detected. As a conclusion, RE can be separated from U and Th. (author)

  12. Electrodialytic separation of Cu(II) and As(V) in acidic electrolytes; Separacion electrodialitica de Cu(II) y As(V) en electrolitos acidos

    Energy Technology Data Exchange (ETDEWEB)

    Ibanez, J. P.; Ipinza, J.; Cifuentes, L.

    2007-07-01

    The separation of copper and arsenic from acidic electrolytes by electrodialysis was investigated at room temperature. the effect of current density and pH was studied in a batch cell during 3 hours. The kinetic parameters showed that Cu(II) transport rate was 0.75 mol/m''2/h and the As(V) transport rate was 0.002 mol/m''2/h. An efficient separation between Cu(II) and As(V) was achieved; Generating a concentrated solution of copper with no arsenic, which was obtained independently of the electrolyte acidity and current density used. The effect of the arsenic speciation with pH is discussed as well. (Author) 23 refs.

  13. The roles of xylan and lignin in oxalic acid pretreated corncob during separate enzymatic hydrolysis and ethanol fermentation

    Science.gov (United States)

    Jae-Won Lee; Rita C.L.B. Rodrigues; Hyun Joo Kim; In-Gyu Choi; Thomas W. Jeffries

    2010-01-01

    High yields of hemicellulosic and cellulosic sugars are critical in obtaining economical conversion of agricultural residues to ethanol. To optimize pretreatment conditions, we evaluated oxalic acid loading rates, treatment temperatures and times in a 23 full factorial design. Response-surface analysis revealed an optimal oxalic acid pretreatment...

  14. Separation of DR synthesized Ti-Mg Alloy by dissolution of waste by-products in acid media

    CSIR Research Space (South Africa)

    Mushove, T

    2010-06-01

    Full Text Available The objective of this work is to isolate synthesized Ti-Mg alloy powder through leaching out of MgO and any unreduced oxides of Titanium. Leaching media investigated are H2SO4, HCl and organic acids ascorbic acid/oxalic and L-cysteine /ascorbic...

  15. Performance of Different Acids on Sandstone Formations

    Directory of Open Access Journals (Sweden)

    M. A. Zaman

    2013-12-01

    Full Text Available Stimulation of sandstone formations is a challenging task, which involves several chemicals and physical interactions of the acid with the formation. Some of these reactions may result in formation damage. Mud acid has been successfully used to stimulate sandstone reservoirs for a number of years. It is a mixture of hydrofluoric (HF and hydrochloric (HCl acids designed to dissolve clays and siliceous fines accumulated in the near-wellbore region. Matrix acidizing may also be used to increase formation permeability in undamaged wells. The change may be up to 50% to 100% with the mud acid. For any acidizing process, the selection of acid (Formulation and Concentration and the design (Pre-flush, Main Acid, After-flush is very important. Different researchers are using different combinations of acids with different concentrations to get the best results for acidization. Mainly the common practice is combination of Hydrochloric Acid – Hydrofluoric with Concentration (3% HF – 12% HCl. This paper presents the results of a laboratory investigation of Orthophosphoric acid instead of hydrochloric acid in one combination and the second combination is Fluoboric and formic acid and the third one is formic and hydrofluoric acid. The results are compared with the mud acid and the results calculated are porosity, permeability, and FESEM Analysis and Strength tests. All of these new combinations shows that these have the potential to be used as acidizing acids on sandstone formations.

  16. Enantioselective separation of dansyl-DL-amino acids and some racemates on "click" functionalized native α-cyclodextrin based sub-2 μm columns.

    Science.gov (United States)

    Ai, Feng; Wang, Yong; Chen, Hui; Yang, Yanhui; Tan, Timothy Thatt Yang; Ng, Siu-Choon

    2013-04-21

    The current work demonstrates that native α-cyclodextrin, anchored onto sub-2 μm silica particles via "click" reactions and packed into a 5 cm column, was found to be effective for the resolution of 11 pairs of dansyl-DL-amino acids (DAAs) using ultra-high performance liquid chromatography (UHPLC). All DAAs were completely or partially separated on the column and the resolution achieved for 7 pairs of DAAs was significantly greater than 1.5. It was found that the buffer type exerted a profound impact on the separation. The effects of analyte substituents adjacent to the chiral center of analytes as well as operation conditions with respect to the separation efficiency were discussed. Five racemic compounds with single or double rings also got resolved on this short α-CD column to some extent.

  17. Performance and techno-economic assessment of several solid-liquid separation technologies for processing dilute-acid pretreated corn stover.

    Science.gov (United States)

    Sievers, David A; Tao, Ling; Schell, Daniel J

    2014-09-01

    Solid-liquid separation of pretreated lignocellulosic biomass slurries is a critical unit operation employed in several different processes for production of fuels and chemicals. An effective separation process achieves good recovery of solute (sugars) and efficient dewatering of the biomass slurry. Dilute acid pretreated corn stover slurries were subjected to pressure and vacuum filtration and basket centrifugation to evaluate the technical and economic merits of these technologies. Experimental performance results were used to perform detailed process simulations and economic analysis using a 2000 tonne/day biorefinery model to determine differences between the various filtration methods and their process settings. The filtration processes were able to successfully separate pretreated slurries into liquor and solid fractions with estimated sugar recoveries of at least 95% using a cake washing process. A continuous vacuum belt filter produced the most favorable process economics. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Separation of L-aspartic acid and L-glutamic acid mixtures for use in the production of bio-based chemicals

    NARCIS (Netherlands)

    Teng, Y.; Scott, E.L.; Sanders, J.P.M.

    2012-01-01

    BACKGROUND: Amino acids are promising feedstocks for the chemical industry due to their chemical functionality. They can be obtained by the hydrolysis of potentially inexpensive protein streams such as the byproduct of biofuel production. However, individual amino acids are required before they can

  19. New Acid Combination for a Successful Sandstone Acidizing

    Science.gov (United States)

    Shafiq, M. U.; Mahmud, H. K. B.; Rezaee, R.

    2017-05-01

    With the development of new enhanced oil recovery techniques, sandstone acidizing has been introduced and played a pivotal role in the petroleum industry. Different acid combinations have been applied, which react with the formation, dissolve the soluble particles; thus increase the production of hydrocarbons. To solve the problems which occurred using current preflush sandstone acidizing technology (hydrochloric acid); a new acid combination has been developed. Core flooding experiments on sandstone core samples with dimensions 1.5 in. × 3 in. were conducted at a flow rate of 2 cm3/min. A series of hydrochloric-acetic acid mixtures with different ratios were tested under 150°F temperature. The core flooding experiments performed are aimed to dissolve carbonate, sodium, potassium and calcium particles from the core samples. These experiments are followed by few important tests which include, porosity-permeability, pH value, Inductively Coupled Plasma (ICP) analysis and Nuclear Magnetic Resonance (NMR measurements). All the results are compared with the results of conventional hydrochloric acid technology. NMR and porosity analysis concluded that the new acid combination is more effective in creating fresh pore spaces and thus increasing the reservoir permeability. It can be seen from the pore distribution before and after the acidizing. Prior applying acid; the large size of pores appears most frequently in the pore distribution while with the applied acid, it was found that the small pore size is most the predominant of the pore distribution. These results are validated using ICP analysis which shows the effective removal of calcium and other positive ions from the core sample. This study concludes that the combination of acetic-hydrochloric acid can be a potential candidate for the preflush stage of sandstone acidizing at high temperature reservoirs.

  20. Optical activity and ultraviolet absorbance detection of dansyl L-amino acids separated by gradient liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    1987-04-01

    Many scientific investigations (e.g., geochronology, pharmaceuticals) have the need to determine enantiometric ratios of amino acids and other compounds. It has been reported that OA/UV or OA/RI (refractive index) are ideal methods for the determination of enantiomeric ratios without the need for chiral columns, chiral eluents, or diasteromer preparation. Unfortunately, only three amino acids are naturally UV absorbing (254 nm), and RI sensitivity for amino acids is low. Derivatization by several methods (o-phthalaldehyde, dansyl, phenylisothiocyanate, fluorescamine, 2,4-dinitrofluorobenzene, and phenylthiohydantoin) renders all amino acids UV absorbing and makes UV or fluorescence viable techniques for amino acids determinations. A previously neglected aspect of derivatization is the effect on optical activity. These highly polar groups influence the chiral center of amino acids drastically (electronic and steric effects). The shifting of the absorption band to the proximity of the wavelength used for OA measurements further enhances the importance of the substituent. The authors report here the determination of 17 dansyl amino acids in a mixture by UV absorbance and optical activity. This involves gradient elution. Previously, the optical activity detector (OAD) has been used only with isocratic HPLC.

  1. Hydrolysis-acidogenesis of food waste in solid-liquid-separating continuous stirred tank reactor (SLS-CSTR) for volatile organic acid production.

    Science.gov (United States)

    Karthikeyan, Obulisamy Parthiba; Selvam, Ammaiyappan; Wong, Jonathan W C

    2016-01-01

    The use of conventional continuous stirred tank reactor (CSTR) can affect the methane (CH4) recovery in a two-stage anaerobic digestion of food waste (FW) due to carbon short circuiting in the hydrolysis-acidogenesis (Hy-Aci) stage. In this research, we have designed and tested a solid-liquid-separating CSTR (SLS-CSTR) for effective Hy-Aci of FW. The working conditions were pH 6 and 9 (SLS-CSTR-1 and -2, respectively); temperature-37°C; agitation-300rpm; and organic loading rate (OLR)-2gVSL(-1)day(-1). The volatile fatty acids (VFA), enzyme activities and bacterial population (by qPCR) were determined as test parameters. Results showed that the Hy-Aci of FW at pH 9 produced ∼35% excess VFA as compared to that at pH 6, with acetic and butyric acids as major precursors, which correlated with the high enzyme activities and low lactic acid bacteria. The design provided efficient solid-liquid separation there by improved the organic acid yields from FW. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. High School Forum: "Invitations to Enquiry": The Calcite/Acid Reaction.

    Science.gov (United States)

    Herron, J. Dudley, Ed.; Driscoll, D. R.

    1979-01-01

    Describes a high school chemistry experiment which involves the reaction between calcite and hydrochloric and sulfuric acids. This reaction can be carried out as a projected demonstration and on an individual basis. (HM)

  3. Reverse-Phase High-Performance Liquid Chromatographic Separation of Methylated and Non-Methylated Nucleic Acid Bases

    OpenAIRE

    Madyastha, Prema; Rao, Pratima; Deobagkar, DN; Madyastha, KM

    1983-01-01

    A high-performance liquid chromatographic sepration method is described for the detection of 5-methylcytosine and 6-methyladenine in nucleic acid ext. The bases were sepd. on a Waters $C18 \\mu$ Bondapak column with a water: methanol acetic acid system. Effluents were monitored by UV absorption at 254 nm. The bases were estd. by peak heights which are proportional to the amts. of the individual bases. The method is rapid, sensitive, easy to perform and reproducible.

  4. Improved separation with the intermittently pressed tubing of multilayer coil in type-I counter-current chromatography.

    Science.gov (United States)

    Yang, Yi; Yang, Jiao; Fang, Chen; Wang, Jihui; Gu, Dongyu; Tian, Jing; Ito, Yoichiro

    2018-05-25

    The intermittently pressed tubing was introduced in type-I counter-current chromatographic system as the separation column to improve the separation performance in the present study. The separations were performed with two different solvent systems composed of 1-butanol-acetic acid-water (4:1:5, v/v) (BAW) and hexane-ethyl acetate-methanol-0.1 M HCl (1:1:1:1, v/v) (HEMW) using dipeptides and DNP-amino acids as test samples, respectively. The chromatographic performance was evaluated in terms of retention of the stationary phase (Sf), theoretical plate (N) and peak resolution (Rs). In general, the type-I planetary motion with the multilayer coil of non-modified standard tubing can yield the best separation at a low revolution speed of 200 rpm with lower flow rate. The present results with intermittently pressed tubing indicated that the performance was also optimal at the revolution speed of 200 rpm where the lower flow rate was more beneficial to retention of stationary phase and resolution. In the moderately hydrophobic two-phase solvent system composed of hexane-ethyl acetate-metanol-0.1 M hydrochloric acid (1:1:1:1, v/v), DNP-amino acids were separated with Rs at 1.67 and 1.47, respectively, with 12.66% of stationary phase retention at a flow rate of 0.25 ml/min. In the polar solvent system composed of 1-butanol-acetic acid-water (4:1:5, v/v), dipeptide samples were resolved with Rs at 2.18 and 18.75% of stationary phase retention at a flow rate of 0.25 ml/min. These results indicate that the present system substantially improves the separation efficiency of type-I counter-current chromatographic system. Published by Elsevier B.V.

  5. Phase separation of in situ forming poly (lactide-co-glycolide acid) implants investigated using a hydrogel-based subcutaneous tissue surrogate and UV-vis imaging.

    Science.gov (United States)

    Sun, Yu; Jensen, Henrik; Petersen, Nickolaj J; Larsen, Susan W; Østergaard, Jesper

    2017-10-25

    Phase separation of in situ forming poly (lactide-co-glycolide acid) (PLGA) implants with agarose hydrogels as the provider of nonsolvent (water) mimicking subcutaneous tissue was investigated using a novel UV-vis imaging-based analytical platform. In situ forming implants of PLGA-1-methyl-2-pyrrolidinone and PLGA-triacetin representing fast and slow phase separating systems, respectively, were evaluated using this platform. Upon contact with the agarose hydrogel, the phase separation of the systems was followed by the study of changes in light transmission and absorbance as a function of time and position. For the PLGA-1-methyl-2-pyrrolidinone system, the rate of spatial phase separation was determined and found to decrease with increasing the PLGA concentration from 20% to 40% (w/w). Hydrogels with different agarose concentrations (1% and 10% (w/v)) were prepared for providing the nonsolvent, water, to the in situ forming PLGA implants simulating the injection site environment. The resulting implant morphology depended on the stiffness of hydrogel matrix, indicating that the matrix in which implants are formed is of importance. Overall, the work showed that the UV-vis imaging-based platform with an agarose hydrogel mimicking the subcutaneous tissue holds potential in providing bio-relevant and mechanistic information on the phase separation processes of in situ forming implants. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Methods development for separation of inorganic anions, organic acids and bases, and neutral organic compounds by ion chromatography and capillary electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jie [Iowa State Univ., Ames, IA (United States)

    1999-04-01

    A novel anion-exchange resin containing three amine groups was prepared by reaction of a chloromethylated polystyrene-divinylbenzene (PS-DVB) resin with diethylenetriamine. After being protonated by contact with an aqueous acid, this resin can be used for ion chromatographic separation of anions. The charge on the resins can be varied from +1 to +3 by changing the mobile phase pH. The selectivity of the new ion exchangers for various inorganic anions was quite different from that of conventional anion exchangers. The performance of this new anion exchanger was studied by changing the pH and the concentration of the eluent, and several different eluents were used with some common anions as testing analytes. Conductivity detection and UV-visible detection were applied to detect the anions after separation. The new resin can also be used for HPLC separation of neutral organic compounds. Alkylphenols and alkylbenzenes were separated with this new polymeric resin, and excellent separations were obtained under simple conditions. This report contains Chapter 1: General introduction and Chapter 6: General conclusions.

  7. Acid-base strengths in pyridine

    NARCIS (Netherlands)

    Bos, M.; Dahmen, E.A.M.F.

    1971-01-01

    Although pyridine is a solvent with a low dielectric constant, spectrophotometric determinations show simple dissociation without ion pairs as intermediates for some sulfonphthaleins and polynitrophenols in pyridine. The salts of a number of amines and hydrochloric acid, perchloric acid and picric

  8. Preparation and evaluation of poly(alkyl methacrylate-co-methacrylic acid-co-ethylene dimethacrylate) monolithic columns for separating polar small molecules by capillary liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Shu-Ling; Wu, Yu-Ru; Lin, Tzuen-Yeuan; Fuh, Ming-Ren, E-mail: msfuh@scu.edu.tw

    2015-04-29

    Highlights: • Methacrylic acid (MAA) was used to increase hydrophilicity of polymeric monoliths. • Fast separation of phenol derivatives was achieved in 5 min using MAA-incorporated column. • Separations of aflatoxins and phenicol antibiotics were achieved using MAA-incorporated column. - Abstract: In this study, methacrylic acid (MAA) was incorporated with alkyl methacrylates to increase the hydrophilicity of the synthesized ethylene dimethacrylate-based (EDMA-based) monoliths for separating polar small molecules by capillary LC analysis. Different alkyl methacrylate–MAA ratios were investigated to prepare a series of 30% alkyl methacrylate–MAA–EDMA monoliths in fused-silica capillaries (250-μm i.d.). The porosity, permeability, and column efficiency of the synthesized MAA-incorporated monolithic columns were characterized. A mixture of phenol derivatives is employed to evaluate the applicability of using the prepared monolithic columns for separating small molecules. Fast separation of six phenol derivatives was achieved in 5 min with gradient elution using the selected poly(lauryl methacrylate-co-MAA-co-EDMA) monolithic column. In addition, the effect of acetonitrile content in mobile phase on retention factor and plate height as well as the plate height-flow velocity curves were also investigated to further examine the performance of the selected poly(lauryl methacrylate-co-MAA-co-EDMA) monolithic column. Moreover, the applicability of prepared polymer-based monolithic column for potential food safety applications was also demonstrated by analyzing five aflatoxins and three phenicol antibiotics using the selected poly(lauryl methacrylate-co-MAA-co-EDMA) monolithic column.

  9. Chip-based CE for rapid separation of 8-aminopyrene-1,3,6-trisulfonic acid (APTS) derivatized glycans

    Czech Academy of Sciences Publication Activity Database

    Smejkal, Petr; Szekrényes, A.; Ryvolová, M.; Foret, František; Guttman, A.; Bek, F.; Macka, M.

    2010-01-01

    Roč. 22, č. 31 (2010), s. 3783-3786 ISSN 0173-0835 R&D Projects: GA MŠk MEB060821 Institutional research plan: CEZ:AV0Z40310501 Keywords : bioanalyzer * chip-based analysis * glycans Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.569, year: 2010

  10. Separation of DR synthesized Ti-Mg Alloy by dissolution of waste by-products in acid media

    CSIR Research Space (South Africa)

    Mushove, T

    2010-06-01

    Full Text Available Of DR Synthesized Ti-Mg Alloy By Dissolution Of Waste By-Products In Acid Media. The dissolution experiments were done in a Julabo SW23 waterbath shaker, with 300 ml flasks. Acid solution of predetermined molarity was charged into a flask and heated... of the diffraction peaks of Mg and TiO2. The reduction of TiO2 at 32hrs of milling was evaluated from Equation 6.2 to be 90.4% (4). Calculated proportions of products, and the respective masses from a 2g sample, are shown in Table 1. Constituent TiO2 Ti-Mg Mg...

  11. Separation and Precipitation of Nickel from Acidic Sulfate Leaching Solution of Molybdenum-Nickel Black Shale by Potassium Nickel Sulfate Hexahydrate Crystallization

    Science.gov (United States)

    Deng, Zhigan; Wei, Chang; Fan, Gang; Li, Xingbin; Li, Minting; Li, Cunxiong

    2018-02-01

    Nickel was separated and precipitated with potassium nickel sulfate hexahydrate [K2Ni(SO4)2·6H2O] from acidic sulfate solution, a leach solution from molybdenum-nickel black shale. The effects of the potassium sulfate (K2SO4) concentration, crystallization temperature, solution pH, and crystallization time on nickel(II) recovery and iron(III) precipitation were investigated, revealing that nickel and iron were separated effectively. The optimum parameters were K2SO4 concentration of 200 g/L, crystallization temperature of 10°C, solution pH of 0.5, and crystallization time of 24 h. Under these conditions, 97.6% nickel(II) was recovered as K2Ni(SO4)2·6H2O crystals while only 2.0% of the total iron(III) was precipitated. After recrystallization, 98.4% pure K2Ni(SO4)2·6H2O crystals were obtained in the solids. The mother liquor was purified by hydrolysis-precipitation followed by cooling, and more than 99.0% K2SO4 could be crystallized. A process flowsheet was developed to separate iron(III) and nickel(II) from acidic-sulfate solution.

  12. Intracranial dialysis measurement of oxytocin, monoamine and uric acid release from the olfactory bulb and substantia nigra of sheep during parturition, suckling, separation from lambs and eating.

    Science.gov (United States)

    Kendrick, K M; Keverne, E B; Chapman, C; Baldwin, B A

    1988-01-26

    Intracranial dialysis was used to measure the release of oxytocin (OXY), monoamines and their metabolites and uric acid (UA) from the substantia nigra (SN) and olfactory bulb (OB) of sheep during parturition, suckling, separation from lambs and eating. Results showed that OXY concentrations increased significantly during parturition, suckling and eating in the SN and during parturition and suckling in the OB. Concentrations of dopamine (DA) increased significantly in the SN during suckling and eating and in the OB during parturition and suckling. The dopamine metabolite, homovanillic acid, also increased significantly in the SN during parturition. Concentrations of the noradrenaline metabolite, 4-hydroxy-3-methoxyphenylethan-1,2-diol (MHPG) and the purine metabolite, UA, were significantly raised during parturition, suckling and separation from the lambs in the SN and increased UA levels were also found during eating. In a separate experiment it was confirmed that OXY was detectable in homogenates of both the SN and the OB. These results show that, in the sheep, OXY and DA release in the SN is associated with maternal and ingestive behaviour whereas similar release in the OB may only be related to maternal behaviour. Release of MHPG in the SN may be associated with maternal behaviour and/or stress.

  13. Acid Rain

    Science.gov (United States)

    Bricker, Owen P.; Rice, Karen C.

    1995-01-01

    Although acid rain is fading as a political issue in the United States and funds for research in this area have largely disappeared, the acidity of rain in the Eastern United States has not changed significantly over the last decade, and it continues to be a serious environmental problem. Acid deposition (commonly called acid rain) is a term applied to all forms of atmospheric deposition of acidic substances - rain, snow, fog, acidic dry particulates, aerosols, and acid-forming gases. Water in the atmosphere reacts with certain atmospheric gases to become acidic. For example, water reacts with carbon dioxide in the atmosphere to produce a solution with a pH of about 5.6. Gases that produce acids in the presence of water in the atmosphere include carbon dioxide (which converts to carbonic acid), oxides of sulfur and nitrogen (which convert to sulfuric and nitric acids}, and hydrogen chloride (which converts to hydrochloric acid). These acid-producing gases are released to the atmosphere through natural processes, such as volcanic emissions, lightning, forest fires, and decay of organic matter. Accordingly, precipitation is slightly acidic, with a pH of 5.0 to 5.7 even in undeveloped areas. In industrialized areas, most of the acid-producing gases are released to the atmosphere from burning fossil fuels. Major emitters of acid-producing gases include power plants, industrial operations, and motor vehicles. Acid-producing gases can be transported through the atmosphere for hundreds of miles before being converted to acids and deposited as acid rain. Because acids tend to build up in the atmosphere between storms, the most acidic rain falls at the beginning of a storm, and as the rain continues, the acids "wash out" of the atmosphere.

  14. Contributions of separate reactions to the acid-base buffering of soils in brook floodplains (Central Forest State Reserve)

    Science.gov (United States)

    Sokolova, T. A.; Tolpeshta, I. I.; Rusakova, E. S.

    2016-04-01

    The acid-base buffering of gleyic gray-humus soils developed in brook floodplains and undisturbed southern-taiga landscapes has been characterized by the continuous potentiometric titration of soil water suspensions. During the interaction with an acid, the major amount of protons (>80%) is consumed for the displacement of exchangeable bases and the dissolution of Ca oxalates. In the O and AY horizons, Mn compounds make the major contribution (2-15%) to the acid buffering. The buffer reactions with the participation of Al compounds make up from 0.5 to 1-2% of the total buffering capacity, and the protonation of the surface OH groups of kaolinite consumes 2-3% of the total buffering capacity. The deprotonation of OH groups on the surface of Fe hydroxides (9-43%), the deprotonation of OH groups on the surface of illite crystals (3-19%), and the dissolution of unidentified aluminosilicates (9-14%) are the most significant buffer reactions whose contributions have been quantified during the interaction with a base. The contribution of the deprotonation of OH groups on the surface of kaolinite particles is lower (1-5%) because of the small specific surface area of this mineral, and that of the dissolution of Fe compounds is insignificant. In the AY horizon, the acid and base buffering of soil in the rhizosphere is higher than beyond the rhizosphere because of the higher contents of organic matter and nonsilicate Fe and Al compounds.

  15. Protein and lipid deposition rates in male broiler chickens : separate responses to amino acids and protein-free energy

    NARCIS (Netherlands)

    Eits, R.M.; Kwakkel, R.P.; Verstegen, M.W.A.; Stoutjesdijk, P.; Greef, de K.H.

    2002-01-01

    Two experiments of similar design were conducted with male broiler chickens over two body weight ranges, 200 to 800 g in Experiment 1 and 800 to 1,600 g in Experiment 2. The data were used to test the hypothesis that protein deposition rate increases (linearly) with increasing amino acid intake,

  16. Continuous fermentation and in-situ reed separation of butyric acid for higher sugar consumption rate and productivity

    DEFF Research Database (Denmark)

    Baroi, George Nabin; Skiadas, Ioannis; Westermann, Peter

    that disconnection of the REED system resulted to much lower (48 and 83% for glucose and xylose, respectively) sugars consumption rates and consequently lower butyric acid production rates. It was also noticeable that continuous operation, even without the REED system, resulted to higher glucose consumption rates...

  17. Separation of thorium and uranium by liquid-liquid extraction from mixed aqueous nitric acidic-methanolic solutions

    International Nuclear Information System (INIS)

    Schmid, E.R.; Kenndler, E.

    1976-01-01

    A method is described for the separation of Th and U from each other and from other elements, usually occuring in minerals, by liquid-liquid extraction with Aliquat Nitrate (tricaprylmethyl ammoniumnitrate, 6 vol%) in benzene from a mixed solution of 2.5 M HNO 3 and methanol (1:1 volume ratio). Permissible upper concentration ratios of interfering elements, such as Li, Na, K, Mg, Ca, Al, Cu, Co(II), Fe(III), Mn(II), Ti(IV), La(III), U(VI), Cl - , ClO 4 - , SO 4 2- , PO 4 3- , have been determined. Following the separation, Th has been determined by spectrophotometry using Thorin, and U by fluorometry. Results for yield under varying conditions, together with elemental concentrations in the ppm range for U and Th in minerals, are given. (B.T.)

  18. The role of omega-3 polyunsaturated fatty acids eicosapentaenoic and docosahexaenoic acids in the treatment of major depression and Alzheimer's disease: Acting separately or synergistically?

    Science.gov (United States)

    Song, Cai; Shieh, Chu-Hsin; Wu, Yi-Shyuan; Kalueff, Allan; Gaikwad, Siddharth; Su, Kuan-Pin

    2016-04-01

    Omega-3 polyunsaturated fatty acids (n-3-PUFAs), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), may improve or prevent some psychiatric and neurodegenerative diseases in both experimental and clinical studies. As important membrane components, these PUFAs benefit brain health by modulating neuroimmune and apoptotic pathways, changing membrane function and/or competing with n-6 PUFAs, the precursors of inflammatory mediators. However, the exact role of each fatty acid in neuroimmune modulation and neurogenesis, the interaction between EPA and DHA, and the best EPA:DHA ratios for improving brain disorders, remain unclear. It is also unknown whether EPA, as a DHA precursor, acts directly or via DHA. Here, we discuss recent evidence of EPA and DHA effects in the treatment of major depression and Alzheimer's disease, as well as their potential synergistic action on anti-inflammatory, antioxidant and neurotrophic processes in the brain. We further analyze the cellular and molecular mechanisms by which EPA, DHA or their combination may benefit these diseases. We also outline the limitations of current studies and suggest new genetic models and novel approaches to overcome these limitations. Finally, we summarize future strategies for translational research in this field. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Extractive separation of Al(III) and Ni(II) by Di-2-Ethylhexyl phosphoric acid-kerosene system from aqueous fluoride medium

    International Nuclear Information System (INIS)

    Islam, M.F.; Begum, D.A.; Rahman, M.; Rahman, M.S.

    2009-01-01

    In the study of the extractive separation of Al(III) and Ni(II) by di-2-ethylhexyl phosphoric acid D2EHPA-kerosene from aqueous fluoride medium, about 94% Al(III) and 2% Ni(II) were extracted with 0.3 M D2EHPA (pH 2.1 and temperature 30+-1 degree C). Extraction of Ni(II) decreased with increasing extractant concentration. D2EHPA-kerosene-fluoride system showed better extraction of Al(III) with higher extractant concentration and aqueous pH and vice versa for the extraction of Ni(II). The maximum separation factor (beta 1380) was obtained for Al(III) at 20 degree C and decreased to (beta 732) at 60 degree C. The separation of Al(III) from Ni(II) was favoured at normal temperature. Extraction followed the order Al(III), Ni(II). About 99% stripping of Al(III) was attained from the loaded 0.20 M D2EHPA. Much faster extraction of Al(III) compared to Ni(II) and preferential loading were shown by D2EHPA-kerosene in the presence of fluoride ion in the aqueous phase. Separation of Al(III) was the most outstanding from Ni-Al-F-complex solution. (author)

  20. Separation of the Stern and diffuse layer in coarse-grained models: the cases of phosphatidyl serine, phosphatidic acid, and PIP2 monolayers.

    Science.gov (United States)

    Vangaveti, S; Travesset, A

    2014-12-28

    We present here a method to separate the Stern and diffuse layer in general systems into two regions that can be analyzed separately. The Stern layer can be described in terms of Bjerrum pairing and the diffuse layer in terms of Poisson-Boltzmann theory (monovalent) or strong coupling theory plus a slowly decaying tail (divalent). We consider three anionic phospholipids: phosphatidyl serine, phosphatidic acid, and phosphatidylinositol(4,5)bisphosphate (PIP2), which we describe within a minimal coarse-grained model as a function of ionic concentration. The case of mixed lipid systems is also considered, which shows a high level of binding cooperativity as a function of PIP2 localization. Implications for existing experimental systems of lipid heterogeneities are also discussed.

  1. Extraction and separation of molybdenum and vanadium from acidic and alkaline media using tertiary and quaternary amines

    International Nuclear Information System (INIS)

    Stas, J.; Dahdouh, A.; Rizkallah, I.

    2010-01-01

    The extraction of vanadium and molybdenum from alkaline leaching solutions coming from the leaching of fly ash of fired electrical power stations by tri-n dodecylamine (TDA) and metyl trioctyl ammonium chloride (QA) in the presence of octanol-2 as modifier in kerosene has been investigated. Some parameters influencing the extraction process have been studied (agitation time, octanol-2 percentage in the organic phase, pH of the aqueous phase, concentration of TDA and QA, concentration of vanadium in the aqueous phase and temperature). It has been shown that the extraction capacity of both V and Mo by TDA increases by decreasing the pH of the aqueous phase and reaches a maximum extraction at pH=2. The concentration of TDA plays an important role on the separation selectivity between these two elements, where the selectivity of Mo vs V (S M o, v=[Mo] o rg/[V] o rg) increases with the decrease of TDA concentration to reach a maximum selectivity value of S M o, v = 0.37 for [TDA]=1.5 M. It has been also shown that, whatever vanadium concentration in the aqueous phase, molybdenum will be first extracted, then the remaining free TDA will be occupied by vanadium. Concerning the quaternary amine QA, the pH value of the aqueous phase plays an important role in the separation process between vanadium and molybdenum, where the value of the selectivity of V vs Mo (S v , Mo=[V] o rg/[Mo] o rg) is maximal for pH>8 and the pH=8.5 is the best value which permit a good separation between these two elements at QA concentration equal to 6%, especially at high vanadium concentration. It is very important to note that for low vanadium concentration and at pH=1.5 the value of the selectivity of Mo vs V (S M o,v) increases with increasing Mo concentration in the aqueous phase which enable us the separation between these two elements under these experimental conditions, where Mo will be much more extracted than vanadium. The stripping of vanadium and molybdenum from the loaded organic

  2. Separation of phenolic acids from monosaccharides by low-pressure nanofiltration integrated with laccase pre-treatments

    DEFF Research Database (Denmark)

    Luo, Jianquan; Zeuner, Birgitte; Morthensen, Sofie Thage

    2015-01-01

    (e.g. dimers and trimers) were mainly responsible for the adsorption fouling. Free laccase treatment was preferred since it was prone to produce large polymeric products while the biocatalytic membrane with immobilized laccase was not suitable as it generated smaller polymers by in-situ product...... monosaccharides (xylose, arabinose, glucose). Four commercial NF membranes (NF270, NP030, NTR7450 and NP010) were evaluated at different pH values and with various laccase pre-treatments (for polymerization of phenolic acids). The results showed that with increasing pH, the retentions of phenolic acids by NF...... could be polymerized by laccase and then completely retained by the NF membranes via size exclusion at pH 5.15. The formation of large polymeric products by laccase could alleviate the irreversible fouling in/on a NF membrane and decrease the monosaccharide retention, while the small polymeric products...

  3. Improved solar light stimulated charge separation of g-C3N4 through self-altering acidic treatment

    Science.gov (United States)

    Leong, Kah Hon; Lim, Ping Feng; Sim, Lan Ching; Punia, Varun; Pichiah, Saravanan

    2018-02-01

    Herein, we report the use of acid treatment to treat g-C3N4 nanostructured by a direct and facile synthesis route. The adopted treatment enhanced photoactivity of g-C3N4 and reflected in the removal of recalcitrant organic pollutant, Bisphenol A under direct sunlight. A complete removal of Bisphenol A was attained in a short duration (225 min) as compared to pure g-C3N4. The analysis clearly substantiated the robustness of acid exfoliation that promoted a blue shift, extended the conjugated length of its respective conduction and valance band. It also drastically prolonged the recombination rate of charge carriers, by producing excess of unpaired electrons in the conduction band for active radicals' generation. Thus, this new findings could offer a new sight of self-alteration in improving the photoactivity of complex organic pollutants for sustainable environmental remediation.

  4. Optimisation methodology in the chiral and achiral separation in electrokinetic chromatography in the case of a multicomponent sample of dansyl amino acids.

    Science.gov (United States)

    Giuffrida, Alessandro; Messina, Marianna; Contino, Annalinda; Cucinotta, Vincenzo

    2013-11-01

    Two different chiral selectors synthesised in our laboratory were used to test the possibility of separation for a sample consisting of ten different enantiomeric pairs of dansyl-derivatives of α-amino acids in electrokinetic chromatography. It was possible to observe all the peaks, though only partly resolved, due to the twenty analytes through an accurate strategy of choice of the experimental conditions. As a part of this strategy, a procedure of identification of the single peaks in the electropherograms called LACI (lastly added component identification) has been developed. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Combination of electromembrane extraction and liquid-phase microextraction in a single step: Simultaneous group separation of acidic and basic drugs

    DEFF Research Database (Denmark)

    Huang, Chuixiu; Seip, Knut Fredrik; Gjelstad, Astrid

    2015-01-01

    at high concentration. This approach was further investigated from human plasma. Extraction recoveries were strongly dependent on dilution of plasma with buffer and on extraction time. Finally, this simultaneous EME/LPME approach was evaluated in combination with liquid chromatography (LC......Electromembrane extraction (EME) and liquid-phase microextraction (LPME) were combined in a single step for the first time to realize simultaneous and clear group separation of basic and acidic drugs. Using 2-nitrophenyl octyl ether as the supported liquid membrane (SLM) for EME and dihexyl ether...

  6. Comparison of Separation of Seed Oil Triglycerides Containing Isomeric Conjugated Octadecatrienoic Acid Moieties by Reversed-Phase HPLC

    OpenAIRE

    Anh Van Nguyen; Victor Deineka; Lumila Deineka; Anh Vu Thi Ngoc

    2017-01-01

    Relative retention analysis and increment approach were applied for the comparison of triglycerides (TGs) retention of a broad set of plant seed oils with isomeric conjugated octadecatrienoic acids (CLnA) by reversed-phase HPLC for “propanol-2-acetonitrile” mobile phases and Kromasil 100-5C18 stationary phase with diode array detection (DAD) and mass spectrometric (MS) detection. The subjects of investigation were TGs of seed oils: Calendula officinalis, Catalpa ovata, Jacaranda mimosifolia, ...

  7. Comparison of Separation of Seed Oil Triglycerides Containing Isomeric Conjugated Octadecatrienoic Acid Moieties by Reversed-Phase HPLC

    Directory of Open Access Journals (Sweden)

    Anh Van Nguyen

    2017-12-01

    Full Text Available Relative retention analysis and increment approach were applied for the comparison of triglycerides (TGs retention of a broad set of plant seed oils with isomeric conjugated octadecatrienoic acids (CLnA by reversed-phase HPLC for “propanol-2-acetonitrile” mobile phases and Kromasil 100-5C18 stationary phase with diode array detection (DAD and mass spectrometric (MS detection. The subjects of investigation were TGs of seed oils: Calendula officinalis, Catalpa ovata, Jacaranda mimosifolia, Centranthus ruber, Momordica charantia, Trichosanthes anguina, Punica granatum, Thladiantha dubia, Valeriana officinalis, and Vernicia montana. It was found that a sequence of elution of TGs of the same types is the same without any inversions for full range of mobile phase compositions: punicic (C18:39Z11E13Z < jacaric (C18:38Z10E12Z < catalpic (C18:39E11E13Z < α-eleostearic (C18:39Z11E13E < calendic (C18:38E10E12Z < β-eleostearic (C18:39E11E13E < all-E calendic (C18:38E10E12E acids. TGs and fatty acid compositions were calculated for all oil samples. Regularities of solute retentions as a function of isomeric conjugated octadecatrienoic acid moiety structure are discussed. Thus, it was proven that it is possible to differentiate TGs of complex composition with moieties of all natural CLnA by retention control accomplished by electronic spectra comparison, even though there are only three types of electronic-vibration spectra for seven isomeric CLnA.

  8. Separation and purification of lactic acid. Thermal catalytic depolymerization of poly-lactic acid into lactide; Hakkoho nyusan no bunri seisei ni kansuru kenkyu. Pori nyusan no rakuchido eno sesshokuteki netsukai jugo

    Energy Technology Data Exchange (ETDEWEB)

    Morita, M.; Hirama, Y.; Liew, M. [Hokkaido National Industrial Research Institute, Sapporo (Japan)

    1996-05-10

    A new separation and purification method for lactic acid from fermentation broth is proposed by which poly-lactic acid produced from unpurified lactic acid is catalytically depolymerized into lactide fractions then further purified into lactide. In the present study, thermal depolymerization catalysts were investigated for commercial use. Iron catalysts, especially metallic iron, and ferrous oxide and lactate, were found to provide almost the same catalytic activity and lactide composition in depolymerization products and those in tin octoate and antimony oxide catalysts. Ferrous oxide was also applied to depolymerize poly-lactic acid derived form unpurified lactic acid to compare catalytic activity and lactide composition and was confirmed to show results similar to those of pure polymer. Based on these findings, it is concluded that iron catalysts can be used commercially. Furthermore, catalytic depolymerization of poly-lactic acids with different molecular weights were studied. Polymers with Mw 5,000-10,000 were found to be better for production of lactide, based on the behavior of depolymerization and lactide content in the product. 5 refs., 9 figs., 1 tab.

  9. Recovery and Separation of Valuable Metals from Spent Nickel-Metal Hydride Batteries using some Organophosphorus Extractants

    International Nuclear Information System (INIS)

    Aly, M.I.; Daoud, J.A.; ALy, H.F.

    2012-01-01

    The separation of cobalt, nickel, and rare earth elements from NiMH battery residues is evaluated in this paper. A hydrometallurgical process is developed for the recovery of metals from spent batteries and a selective separation of RE by precipitation of sodium RE double sulfate is performed. The methodology used benefits the solubility of the battery electrode materials in sulfuric or hydrochloric acids. The results obtained show that sulfuric acid is slightly less powerful in leaching (NiMH) compared to HCl acid. However, sulfuric acid was used on economic basis. Leaching solution was obtained by using 3 M H 2 SO 4 at 70 +1 degree C + 3% wt. H 2 O 2 for 5 hours. It has been shown that it is possible to recover about 98 % of the RE contained in spent NiMH batteries. The maximum recovery of nickel and cobalt metals was 99.9% and 99.4%, respectively. The effects of the main operating variables of both leaching and solvent extraction steps of nickel (II) and cobalt (II) from the leach solution using HDEHP (di-2-ethylhexyl phosphoric acid) and CYANEX 272 (di-(2,4,4 trimethyl pentyl) phosphinic acid) in kerosene were investigated aiming to maximize metal separation for recycling purposes. The developed process for the recovery and separation of nickel (II) , cobalt (II), and rare earth from spent NiMH batteries is tested and the obtained sulfate salts CoSO 4 and NiSO 4 have a high purity, suggesting that these recovered products could be used as chemical materials without further purification

  10. Modelling extraction and separation of some alpha-transition elements from acidic media by synergic combinations of aromatic polyimines and micellar cationic exchangers

    International Nuclear Information System (INIS)

    Vitart, X.; Musikas, C.

    1988-01-01

    In this paper is emphasized, taking the extraction and separation by Dinonylnaphtalene sulfonic acid (HDMNS)of ruthenium-rhodium from a nitric acid media and nickel-cobalt from a sulfuric acid media as examples, the quantified chemical equilibria involved in order to elucidate the extraction mechanism. Reactions in aqueous media were investigated within three aspects: kinetics of formation, stability of metal complexes, ionic associations between complexes and mineral anions present in acidic media. This last point explains partly the selectivity of the system. The behaviour of HDNNS within extraction conditions, was studied leading to the structure of the micelle and to the quantification of equilibria involved (critical micelle concentration, polymerisation constant, etc...). Ligand extraction was studied previously to metal complexes extraction since the general mechanism of the system proceeds as a competitive extraction of cationic species in aqueous media (protonated forms of the free ligand, cationic metal complexes). The modelling of independent extraction of metals was used to predict numerically the behaviour of a multicomponent system where few metals are initially in aqueous media. These simulations are in accordance with experimental results

  11. An electron conductive polymer, poly-aniline, in gas separation: optimisation of transport properties by alternated acid-base treatment

    International Nuclear Information System (INIS)

    Rebattet, Laurence

    1994-01-01

    The objective of this research thesis is to study the variation of gas permeation properties of poly-aniline during a doping/de-doping/re-doping cycle, and to study the evolution of the separation power of this polymer. Scanning electronic microscopy is used to study the microstructure and more particularly how the doping agent is distributed within the polymer. Permeabilities, diffusion coefficients, sorption solubilities and interaction energies are measured by using coupled permeation and micro-gravimetry-calorimetry methods. A range of gases (H 2 , O 2 , CO 2 , N 2 , CH 4 ) is analysed [fr

  12. Facile synthesis of improved room temperature gas sensing properties of TiO2 nanostructures: Effect of acid treatment

    CSIR Research Space (South Africa)

    Tshabalala, Zamaswazi P

    2016-03-01

    Full Text Available TiO2 nanoparticles were synthesized via a simple hydrothermal method in a sodium hydroxide (NaOH) aqueous solution and washed with distilled water and different concentrations of hydrochloric acid which acted as the morphological...

  13. Web technology in the separation of strontium and cesium from INEL-ICPP radioactive acid waste (WM-185)

    International Nuclear Information System (INIS)

    Bray, L.A.; Brown, G.N.

    1995-01-01

    Strontium and cesium were successfully removed from radioactive acidic waste (WM-185) at the Idaho National Engineering Laboratory, Idaho Chemical Processing Plant (ICPP), with web technology from 3M and IBC Advanced Technologies, Inc. (IBC). A technical team from Pacific Northwest Laboratory, ICPP, 3M and IBC conducted a very successful series of experiments from August 15 through 18, 1994. The ICPP, Remote Analytical Laboratory, Idaho Falls, Idaho, provided the hot cell facilities and staff to complete these milestone experiments. The actual waste experiments duplicated the initial 'cold' simulated waste results and confirmed the selective removal provided by ligand-particle web technology

  14. Influence of the use of acids and films in post-harvest lychee conservation

    Directory of Open Access Journals (Sweden)

    Danielle Fabíola Pereira da Silva

    2012-12-01

    Full Text Available Lychee (Litchi chinensis Sonn. has a high commercial value; however, it has a short shelf-life because of its rapid pericarp browning. The objective of this study was to evaluate the shelf-life of 'Bengal' lychee fruits stored after treatment with hydrochloric acid and citric acid, associated with cassava starch and plastic packaging. Uniformly red pericarp fruits were submitted to treatments: 1-(immersion in citric acid 100 mM for 5 minutes + cassava starch 30 g L-1 for 5 minutes, 2-(immersion in hydrochloric acid 1 M for 2 minutes + starch cassava 30 g L-1 for 5 minutes, 3-(immersion in citric acid 100 mM for 5 minutes + polyvinyl chloride film (PVC, 14 µm thick and 4-(immersion in hydrochloric acid 1 M for 2 minutes + PVC film. During 20 days, the fruits were evaluated for mass loss, pericarp color, pH, soluble solids and titratable acidity, vitamin C of the pulp and pericarp and activities of polyphenol oxidase and peroxidase of the pericarp. The treatment with hydrochloric acid associated with PVC was the most effective in maintaining the red color of the pericarp for a period of 20 days and best preservation of the fruit. The cassava starch associated with citric acid, and hydrochloric acid did not reduce the mass loss and did not prevent the browning of lychee fruit pericarp.

  15. Separations chemistry

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Infrared spectra of Pu(IV) polymer show effects of CO 2 adsorption and of aging. Uv light (300 nm) increases the rate of reduction of PuO 2 2+ and Pu 4+ to Pu 3+ and the Pu--U separation factor using TBP. Distribution ratios for Zr and Hf between Dowex 50W--X8 resin and H 2 SO 4 solutions were found to decrease sharply with H 2 SO 4 content. Octylphenyl acid phosphate, a mixture of monooctylphenyl and dioctylphenyl phosphoric acids, is being studied for U recovery from wet-process phosphoric acid. A study of HNO 3 leaching of Ra from U ores was completed. Effects of particle size of the packed bed on the dispersion of the boundary of the miscible phase used in oil recovery are being studied. Effects of sulfonates on toluene--n-butanol--water phase relations were determined, as were the effects of salts and solutes on the max water content of 1:1 toluene--alcohol solutions. A study was begun of hydrocarbon solubility in water--surfactant--alcohol. The mechanism of the formation of hydrous ZrO 2 --polyacrylate membranes and their use for sulfate rejection were studied. Salt rejection through hyperfiltration by clay membranes (bentonite and kaolin) was also investigated. Preliminary results are given for hyperfiltration of wood-pulping wastes by ZrO 2 membranes. 13 figures

  16. Peak broadening in paper chromatography and related techniques VI. The efficiency of various kinds of chromatography paper and thin-layer cellulose powder for the separation of amino acids

    NARCIS (Netherlands)

    Ligny, C.L. de; Kok, E.C.M.

    1968-01-01

    The efficiency of several chromatography papers and thin-layer cellulose powders for the separation of amino acids is investigated, using the minimum elution time for a given resolution as the criterion.

  17. Separation of acid blue 25 from aqueous solution using water lettuce and agro-wastes by batch adsorption studies

    Science.gov (United States)

    Kooh, Muhammad Raziq Rahimi; Dahri, Muhammad Khairud; Lim, Linda B. L.; Lim, Lee Hoon; Chan, Chin Mei

    2018-05-01

    Three plant-based materials, namely water lettuce (WL), tarap peel (TP) and cempedak peel (CP), were used to investigate their potentials as adsorbents using acid blue 25 (AB25) dye as a model for acidic dye. The adsorbents were characterised using Fourier transform infrared spectroscopy, X-ray fluorescence and scanning electron microscope. Batch experiments involving parameters such as pH, temperature, contact time, and initial dye concentration were done to investigate the optimal conditions for the adsorption of AB25 onto the adsorbents. Thermodynamics study showed that the uptake of AB25 by the three adsorbents was feasible and endothermic in nature. Both the Langmuir and Freundlich isotherm models can be used to describe the adsorption process of AB25 onto WL and CP while pseudo-second-order fitted the kinetics data, suggesting that chemisorptions were majorly involved. The use of 0.1 M of NaOH showed the best results in regenerating of the WL, TP and CP's adsorption ability after AB25 treatment.

  18. Selection of suitable mineral acid and its concentration for biphasic dilute acid hydrolysis of the sodium dithionite delignified Prosopis juliflora to hydrolyze maximum holocellulose.

    Science.gov (United States)

    Naseeruddin, Shaik; Desai, Suseelendra; Venkateswar Rao, L

    2016-02-01

    Two grams of delignified substrate at 10% (w/v) level was subjected to biphasic dilute acid hydrolysis using phosphoric acid, hydrochloric acid and sulfuric acid separately at 110 °C for 10 min in phase-I and 121 °C for 15 min in phase-II. Combinations of acid concentrations in two phases were varied for maximum holocellulose hydrolysis with release of fewer inhibitors, to select the suitable acid and its concentration. Among three acids, sulfuric acid in combination of 1 & 2% (v/v) hydrolyzed maximum holocellulose of 25.44±0.44% releasing 0.51±0.02 g/L of phenolics and 0.12±0.002 g/L of furans, respectively. Further, hydrolysis of delignified substrate using selected acid by varying reaction time and temperature hydrolyzed 55.58±1.78% of holocellulose releasing 2.11±0.07 g/L and 1.37±0.03 g/L of phenolics and furans, respectively at conditions of 110 °C for 45 min in phase-I & 121 °C for 60 min in phase-II. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. A Fine-Tuned MOF for Gas and Vapor Separation: A Multipurpose Adsorbent for Acid Gas Removal, Dehydration, and BTX Sieving

    KAUST Repository

    Haja Mohideen, Mohamed Infas; Pillai, Renjith S.; Adil, Karim; Bhatt, Prashant; Belmabkhout, Youssef; Shkurenko, Aleksander; Maurin, Guillaume; Eddaoudi, Mohamed

    2017-01-01

    Summary The development of highly stable separation agents is recognized as a decisive step toward the successful deployment of energy-efficient and cost-effective separation processes. Here, we report the synthesis and construction of a metal-organic framework (MOF), kag-MOF-1, that has adequate structural and chemical features and affords a stable adsorbent with unique and appropriate adsorption properties for gas processing akin to acid gas removal, dehydration, and benzene-toluene-xylene (BTX) sieving. A combination of X-ray diffraction experiments, adsorption studies, mixed-gas breakthrough adsorption column testing, calorimetric measurements, and molecular simulations corroborated the exceptional separation performance of kag-MOF-1 and its prospective use as a multifunctional adsorbent. The unique adsorption properties of kag-MOF-1, resulting from the contracted pore system with aligned periodic array of exposed functionalities, attest to the prominence of this new generation of ultra-microporous material as a prospective practical adsorbent toward cost-effective and more simplified gas and vapor processing flowcharts for natural gas upgrading and flue gas scrubbing.

  20. Investigation of Mixed Chiral Selectors of Different Metal Ion-L-Alanine Complex and β-Cyclodextrin on the Chiral Separation of Dansyl Amino Acids with Capillary Electrophoresis

    Institute of Scientific and Technical Information of China (English)

    郑志侠; 屈锋; 林金明

    2003-01-01

    Chiral separation of dausyl amino acids by capillary electrophoresis using mixed selectors of Mn(ll)-L-alanine complex and β-cyclodextrin (β-CD) was studied. Resolution was considerably superior to that obtained by using either Mn (Ⅱ)-L-alanine complex or β-CD alone. The effects of separation parameters, such as pH value of buffer solution, capillary temperature, the concentration of Mn (Ⅱ)-L-alanine complex, the types of CD and ligand on the migration times and resolutions were investigated. Six different transition metal complexes,Cu(Ⅱ), Zn(Ⅱ), Co(Ⅱ), Ni(Ⅱ), Hg(Ⅱ) and Cd(Ⅱ)-L-alanine complexes have been employed and compared with Mn(Ⅱ)complex. Differences in retention and selectivity were found.The substitution of Cu(Ⅱ), Zn(Ⅱ), Co(Ⅱ) and Ni(Ⅱ) for Mn(Ⅱ) resulted in a better chiral resolution while Hg(Ⅱ) and Cd(Ⅱ) showed poorer resolution abilities. The chiral separation mechanism was also discussed briefly.

  1. A Fine-Tuned MOF for Gas and Vapor Separation: A Multipurpose Adsorbent for Acid Gas Removal, Dehydration, and BTX Sieving

    KAUST Repository

    Haja Mohideen, Mohamed Infas

    2017-10-19

    Summary The development of highly stable separation agents is recognized as a decisive step toward the successful deployment of energy-efficient and cost-effective separation processes. Here, we report the synthesis and construction of a metal-organic framework (MOF), kag-MOF-1, that has adequate structural and chemical features and affords a stable adsorbent with unique and appropriate adsorption properties for gas processing akin to acid gas removal, dehydration, and benzene-toluene-xylene (BTX) sieving. A combination of X-ray diffraction experiments, adsorption studies, mixed-gas breakthrough adsorption column testing, calorimetric measurements, and molecular simulations corroborated the exceptional separation performance of kag-MOF-1 and its prospective use as a multifunctional adsorbent. The unique adsorption properties of kag-MOF-1, resulting from the contracted pore system with aligned periodic array of exposed functionalities, attest to the prominence of this new generation of ultra-microporous material as a prospective practical adsorbent toward cost-effective and more simplified gas and vapor processing flowcharts for natural gas upgrading and flue gas scrubbing.

  2. Flotation-separation and ICP-AES determination of ultra trace amounts of copper, cadmium, nickel and cobalt using 2-aminocyclopentene-1-dithiocarboxylic acid.

    Science.gov (United States)

    Shamsipur, Mojtaba; Hashemi, Omid Reza; Safavi, Afsaneh

    2005-09-01

    A rapid flotation method for separation and enrichment of ultra trace amounts of copper(II), cadmium(II), nickel(II) and cobalt(II) ions from water samples is established. At pH 6.5 and with sodium dodecylsulfate used as a foaming reagent, Cu2+, Cd2+, Ni2+ and Co2+ were separated simultaneously with 2-aminocyclopentene-1-dithiocarboxylic acid (ACDA) added to 1 l of aqueous solution. The proposed procedure of preconcentration is applied prior to the determination of these four analytes using inductivity coupled plasma-atomic emission spectrometry (ICP-AES). The effects of pH, concentration of ACDA, applicability of different surfactants and foreign ions on the separation efficiency were investigated. The preconcentration factor of the method is 1000 and the detection limits of copper(II), cadmium(II), nickel(II) and cobalt(II) ions are 0.078, 0.075, 0.072 and 0.080 ng ml(-1), respectively.

  3. Separation of uranium from rare earths in chloride medium using Alamine 336

    International Nuclear Information System (INIS)

    Mondal, S.; Giriyalkar, A.B.; Singh, A.K.; Hubli, R.C.

    2014-01-01

    Present work was carried out to optimize a process to separate uranium from rare earths using Alamine-336 (tri-n-octyl amine). This paper describes the process of extraction of uranium from chloride liquor generated after dissolution of impure SDU cake in hydrochloric acid. The solvent used in this study is Alamine-336 which was procured from M/s. Chemical Centre, Mumbai. Dodecane was used as diluent and isodecanol as phase modifier. The extraction and stripping experiments were carried out in separating funnels shaken manually at room temperature. The contact time was fixed at five minutes for all the experiments. Following contact, the aqueous phase and the organic phase were separated and the aqueous phase was taken up for analysis. Analysis of uranium and rare earths were done by ICP-AES. Metal extraction by amines depends on the capacity of the metallic ions to form anionic/neutral species in the aqueous media; these species are then extracted by anion exchange mechanism or by adduct formation respectively

  4. The viability of MCM-41 as separator in secondary alkaline cells

    Science.gov (United States)

    Meskon, S. R.; Othman, R.; Ani, M. H.

    2018-01-01

    The viability of MCM-41 membrane as a separator material in secondary alkaline cell is investigated. The inorganic membrane was employed in an alkaline nickel-zinc system. MCM-41 mesoporous material consists of arrays of hexagonal nano-pore channels. The membrane was synthesized using sol-gel route from parent solution comprising of quarternary ammonium surfactant, cethyltrimethylammonium bromide C16H33(CH3)3NBr (CTAB), hydrochloric acid (HCl), deionized water (H2O), ethanol (C2H5OH), and tetraethylortosilicate (TEOS). Both the anodic zinc/zinc oxide and cathodic nickel hydroxide electrodeposited film were coated with MCM-41 membrane. The Ni/MCM-41/Zn alkaline cell was then subjected to 100-cycle durability test and the structural stability of MCM-41 separator throughout the progression of the charge-discharge cycles is studied. X-ray diffraction (XRD) analysis on the dismantled cell shows that MCM-41 began to transform to lamellar MCM-50 on the 5th cycle and transformed almost completely on the 25th cycle. The phase transformation of MCM-41 hexagonal structure into gel-like MCM-50 prevents the mesoporous cell separator from diminished in the caustic alkaline surround. This work has hence demonstrated MCM-41 membrane is viable to be employed in secondary alkaline cells.

  5. Radiochemical separation of {sup 231}Pa from siliceous cake prior to its determination by gamma ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Dalvi, Aditi A. [Bhabha Atomic Research Centre, Mumbai (India). Analytical Chemistry Div.; Homi Bhabha National Institute, Mumbai (India); Verma, Rakesh

    2017-07-01

    A simple and fast radiochemical method for the separation of protactinium ({sup 231}Pa) from siliceous cake for its determination by gamma ray spectrometry is described. The method involves (a) a novel approach, the fusion of the siliceous cake with sodium peroxide, (b) the dissolution of the fused mass in nitric acid and (c) the co-precipitation of {sup 231}Pa with manganese dioxide formed in-situ by the addition of solid manganous sulfate and potassium permanganate to the solution. The fusion, effected in a single step, is simpler and highly effective in comparison to methods reported hitherto in literature. The radiochemical yield of {sup 231}Pa, determined using 311.9 keV gamma ray of {sup 233}Pa radiotracer is quantitative (∝90%). The decontamination factors calculated using gamma ray spectrometry and energy dispersive X-ray fluorescence measurements show that the separation from the interfering radionuclides is high whereas separation from major and minor elements is good. Separation by ion-exchange method in hydrochloric acid, hydrofluoric acid and oxalic acid media have comparatively much lower yields. The concentration of {sup 231}Pa in the siliceous cake measured using interference-free 283.6 keV gamma ray was found to be (6.4 ± 0.33) μg kg{sup -1}. The measured concentration of {sup 231}Pa was well above the limit of quantitation whereas the coefficient of variation was ∝5%. The improvement in the limit of detection was due to the reduction in spectral background. Systematic evaluation of various uncertainty parameters showed that the major contributors to the combined uncertainty were efficiency of the high purity germanium detector and the counting statistics. The present sample decomposition and separation methods are robust, simple to perform and can be effectively used for the determination and hence source prospecting of protactinium.

  6. Membrane-Based Separation of Phenol/Water Mixtures Using Ionically and Covalently Cross-Linked Ethylene-Methacrylic Acid Copolymers

    Directory of Open Access Journals (Sweden)

    Alexander Mixa

    2008-01-01

    Full Text Available Membrane-based separation of phenol/water mixtures with concentrations of phenol between 3 wt% and 8 wt% in the feed has been performed with nonmodified as well as cross-linked ethylene-methacrylic acid (E-MAA copolymers with different amounts of methacrylic acid. As cross-linking agents, aluminium acetyl acetonate, which leads to ionically cross-linked membranes, and 2,3,5,6-tetramethyl-1,4-phenylene diamine and glycerine digycidether, leading to covalently cross-linked membranes, have been used. Generally, it was found that with increasing phenol content in the feed, the total flux is increasing whereas the enrichment factor is decreasing. Using nonmodified membranes with higher methacrylic acid monomer content in the polymer, lower fluxes and higher enrichment factors were observed. Investigation of different cross-linked membranes showed that with high phenol concentration in the feed, ionic cross-linking seems to be very promising. Furthermore, variation of feed temperature shows that ionically cross-linked membranes reached higher fluxes as well as higher enrichment factors at elevated temperatures. The temperature-dependent data were fitted based on an Arrhenius-type equation, and activation energies for the permeation of phenol and water through the membrane were calculated.

  7. Separation Of Uranium From Fission Products Zr And Ru With 30% TBP (Tri Butyl Phosphate) Dodecane In Nitric Acid Medium As An Extract Material

    International Nuclear Information System (INIS)

    Herdady, R. Didiek; Masduki, Busron; Sigit

    2000-01-01

    Separation of uranium from fission products Zr and Ru in batch process with Tbp 30% - dodecane in nitric acid medium has been investigated. The extraction was carried out on various acidity of 1,006 M, 1.990 M, 2,980 M, 4,006 M, and 5,006 M, and uranium concentration in feed of 100.30 g/l; 149.96 g/l, 250.30 g/l and 300.7 g/l. The results showed that equilibrium of extraction was achieved at 25 minutes, enhancement factor of ruthenium increased and of zirconium decreased Utilization of grand concentration of uranium in feed caused decreasing of distribution coefficient, zirconium and ruthenium. The better contribution of experiments was obtained at the acidity of 2 M and uranium concentration in feed of 149.9 g/l with the decontamination factor of zirconium, FD zr-u was 1,65 and of ruthenium, FD ru-u was 1,52

  8. Investigation of an Electrochemical Method for Separation of Copper, Indium, and Gallium from Pretreated CIGS Solar Cell Waste Materials

    Directory of Open Access Journals (Sweden)

    Anna M. K. Gustafsson

    2015-01-01

    Full Text Available Recycling of the semiconductor material copper indium gallium diselenide (CIGS is important to ensure a future supply of indium and gallium, which are relatively rare and therefore expensive elements. As a continuation of our previous work, where we recycled high purity selenium from CIGS waste materials, we now show that copper and indium can be recycled by electrodeposition from hydrochloric acid solutions of dissolved selenium-depleted material. Suitable potentials for the reduction of copper and indium were determined to be −0.5 V and −0.9 V (versus the Ag/AgCl reference electrode, respectively, using cyclic voltammetry. Electrodeposition of first copper and then indium from a solution containing the dissolved residue from the selenium separation and ammonium chloride in 1 M HCl gave a copper yield of 100.1 ± 0.5% and an indium yield of 98.1 ± 2.5%. The separated copper and indium fractions contained no significant contamination of the other elements. Gallium remained in solution together with a small amount of indium after the separation of copper and indium and has to be recovered by an alternative method since electrowinning from the chloride-rich acid solution was not effective.

  9. Separation of the noble metals ruthenium and palladium from nitric acid solution of the nuclear fuel reprocessing containing complexing agents

    International Nuclear Information System (INIS)

    Ghafourian, H.

    1989-06-01

    Two extraction chromatographic techniques have been developed. N'N diethylthiourea (DETU), which forms complexes with ruthenium that can be retained on an AG50W-X2 ion exchanger, has proved to be a suitable reagent. The structures of these complexes were elucidated by electrophoresis, ion exchange and IR spectroscopy. Under the same conditions Pd forms an insoluble DETU-complex of the formula [Pd(DETU) 4 ] 2+ , which allows the separation of this metal quantitatively. With regard to the application of the developed technique for recovery of the mentioned noble metals from dissolver residues of the nuclear fuel reprocessing, comparative studies were carried out for accompanying fission product nuclides and actinides such as Mo, Tc, Zr, Ce, U and Pu. It was found out that no complex between diethylthiourea and the fission products zirconium, molybdenum and cerium and the actinides uranium, plutonium and americium were formed. Technetium, which was originally present as pertechnetate, is reduced to Tc(IV) and retained on the cation exchanger together with ruthenium. Ruthenium was eluted with 6 M HNO 3 . The efficiency of the developed process has been demonstrated with simulated solutions. The achieved decontamination factors ranged from 10 2 to 10 6 depending on the nuclide. (orig./RB) [de

  10. Isolation of living Algae growing in the shells of Molluscs and Barnacles with EDTA (ethylenediaminetetraacetic acid)

    NARCIS (Netherlands)

    Prud’homme van Reine, W.F.; Hoek, van den C.

    1966-01-01

    Several decalcifying mixtures or aqueous solutions of inorganic or organic acids are generally used for releasing algae growing in the shells of molluscs and barnacles, for instance dilute hydrochloric, nitric, citric, or acetic acid (4), a mixture of nitric acid, chromic acid and alcolhol (1),

  11. Sulfur isotope separation by anion exchange chromatography: 34 S isotope enrichment

    International Nuclear Information System (INIS)

    Bendassolli, Jose Albertino; Trivelin, Paulo Cesar O.; Carneiro Junior, Francisco

    1995-01-01

    The 34 S isotope separation was carried out by isotopic exchange reactions between sulphurous acid in solution and bisulphite anions adsorbed on an ammonium quaternary (Dowex 1 x 8 and Dowex 2 x 8, 100-200 mesh) anion exchange resin packed in columns. Each resin column had 130 cm length and 2.2 cm diameter. The columns were connected in series during displacement of bisulphite bands. For the experiments, a band of bisulphite was fixed to the anion resin, initially in the hydroxyl ion form, and subsequently eluted with 0.2 0.3, 0.4 and 0.6 mol L -1 HCL solution. The hydrochloric acid solution was kept under a nitrogen atmosphere at 245 KPa of pressure, in order to prevent the evolution of gases and also the oxidation of the bisulphite. The experiments showed that the best results were obtained with the elution of bisulphite with 0.2 mol.L -1 HCL, with the Dowex 1 x 8 resin. Enrichments in 34 S of 17.33 atoms% were obtained using Dowex 1 x 8 resin, 0.2 mol.L -1 HCL solution and band displacement of 50 m. Replacing the depleted portion of the band with natural bisulphite, for each 10 m of band displacement, produced 6.79 mmol of sulphurous acid enriched with approximately 17% of 34 S, after 14 m of band dislocation. (author). 7 refs., 1 fig., 2 tabs

  12. Separation of 1,3-substituted imidazoles for quality control of a Lewis acidic ionic liquid for aluminum electroplating.

    Science.gov (United States)

    Kosmus, Patrick; Steiner, Oliver; Goessler, Walter; Gollas, Bernhard

    2014-05-01

    Ionic liquids (ILs) are already used or have great potential in many industrial applications. Knowledge about their unique physicochemical characteristics makes ILs suitable for the electrodeposition of metals with very low negative potentials. Aluminum with its good corrosion protection behavior has great capability to be electroplated from IL electrolytes on steel substrates. The stability of the chosen electrolyte is very important to ensure industrial applicability. In this study, temperature and electrochemical long-term stability from electrolytes based on a Lewis acidic mixture of AlCl3 and 1-ethyl-3-methylimidazolium chloride are investigated. A published method was modified to identify possible degradation products using mass spectrometric detection. The optimized method used an Agilent Zorbax SB-Phenyl column (2.0 × 150 mm, 5 μm particles) with a 20 mmol TFA and 5% ACN mobile phase. This method allowed the quantification of several imidazoles from 0.1 to 100 mg/L. When analyzing the long-term stressed electrolytes, no significant changes in electrolyte composition could be observed. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Amino acids separation with the tetracarboxylic derived of the para-ter-butylcalix[4]arene by means of solid-liquid extraction assisted with lanthanides

    International Nuclear Information System (INIS)

    Bernal R, R. del C.

    2014-01-01

    The tetracarboxylic derived of the para-ter-butylcalix[4]arene (B 4 ACEbL 4 ) does not exist commercially for what was synthesized and characterized at laboratory level. The separation of the L-tyrosine amino acid was studied by means of a solid-liquid extraction system with the B 4 ACEbL 4 as solid phase, in function of ph (2.5-7.5) and contact time (5 and 15 hours) to temperature of 15-17 grades C. Resulted that the ph and the contact time were decisive in the extraction percentage of water tyrosine. The lowest percentage was 49% to ph 4 and the highest percentage was 61% to ph 7.5 with 15 hours of contact. In a contact time of 5 hours the extraction was inferior to 32% (ph 4) and of 47% to ph 6.5. The europium effect (Eu (III)) was studied to ph acid in the tyrosine separation and was found that the tyrosine extraction is not increased neither decomposes in europium presence, this is simultaneously extracted by the calixarene but it does not enter in competition for the calixarene with the amino acid. The separate solid phases: calixarene-tyrosine was analyzed by Far infrared radiation (Fir), Mid-Infrared (Mir) spectroscopy and luminescence to check the tyrosine presence in the separate solids as well as the nature of the connection calixarene-tyrosine. In this way was possible to check the tyrosine presence and to propose the formed molecular species tyrosine-calixarene, those which interact mainly by means of hydrogen connections and Van der Waals forces. The liquid phases before and after the extraction were analyzed by UV-Vis spectrophotometry and luminescence. The Neutron activation analysis was used to determine the europium content in the solid and liquid phases of extractions in europium presence. The tyrosine degradation also shows dependence with the ph, obtaining 88% degradation to the 24 hours to ph 7.5, while to ph 3 is degraded the 54% of tyrosine present in the sample. The europium presence does not affect the tyrosine extraction but if its photo

  14. Further study of extraction equilibrium of uranium(VI) with dicyclohexano-18-crown-6 and its application to separating uranium and thorium

    International Nuclear Information System (INIS)

    Wang Wenji; Sun Qing; Chen Bozhong

    1987-01-01

    The extraction equilibrium of uranium(VI) from aqueous hydrochloric acid solution with dicyclohexano-18-crown-6 isomer A (Ia) and isomer B (Ib) in 1,2-dichloroethane is presented. The extracted species are found to be 1:2 (metal/crown) for Ia and 2:3 for Ib from slope analysis and direct determination of extracted complexes. The extraction equilibrium constants (Kex) were determined at 25 deg C, and were equal to 29.5 for the former and 0.208 for the latter. It is concluded that Ia has stronger coordinate ability for uranium than Ib. The method is effective and selective. The results can be used for the separation of uranium and thorium. (author)

  15. Simultaneous separation of copper, cadmium and cobalt from sea-water by co-flotation with octadecylamine and ferric hydroxide as collectors.

    Science.gov (United States)

    Cabezon, L M; Caballero, M; Cela, R; Perez-Bustamante, J A

    1984-08-01

    A method is proposed for the simultaneous quantitative separation of traces ofCu(II), Cd(II) and Co(II) from sea-water samples by means of the co-flotation (adsorbing colloid flotation) technique with ferric hydroxide as co-precipitant and octadecylamine as collector. The experimental parameters have been studied and optimized. The drawbacks arising from the low solubility of octadecylamine and the corresponding sublates in water have been avoided by use of a 6M hydrochloric acid-MIBK-ethanol (1:2:2 v v ) mixture. The results obtained by means of the proposed method have been compared with those given by the usual ammonium pyrrolidine dithiocarbamate/MIBK extraction method.

  16. Complementary DNA and derived amino acid sequence of the α subunit of human complement protein C8: evidence for the existence of a separate α subunit messenger RNA

    International Nuclear Information System (INIS)

    Rao, A.G.; Howard, O.M.Z.; Ng, S.C.; Whitehead, A.S.; Colten, H.R.; Sodetz, J.M.

    1987-01-01

    The entire amino acid sequence of the α subunit (M/sub r/ 64,000) of the eight component of complement (C8) was determined by characterizing cDNA clones isolated from a human liver cDNA library. Two clones with overlapping inserts of net length 2.44 kilobases (kb) were isolated and found to contain the entire α coding region [1659 base pairs (bp)]. The 5' end consists of an untranslated region and a leader sequence of 30 amino acids. This sequence contains an apparent initiation Met, signal peptide, and propeptide which ends with an arginine-rich sequence that is characteristic of proteolytic processing sites found in the pro form of protein precursors. The 3' untranslated region contains two polyadenylation signals and a poly(A)sequence. RNA blot analysis of total cellular RNA from the human hepatoma cell line HepG2 revealed a message size of ∼2.5 kb. Features of the 5' and 3' sequences and the message size suggest that a separate mRNA codes for α and argues against the occurrence of a single-chain precursor form of the disulfide-linked α-λ subunit found in mature C8. Analysis of the derived amino acid sequence revealed several membrane surface seeking domains and a possible transmembrane domain. Analysis of the carbohydrate composition indicates 1 or 2 asparagine-linked but no O-linked oligosaccharide chains, a result consistent with predictions from the amino acid sequence. Most significantly, it exhibits a striking overall homology to human C9, with values of 24% on the basis of identity and 46% when conserved substitutions are allowed. As described in an accompanying report this homology also extends to the β subunit of C8

  17. Separation of trivalent actinides and lanthanides with some substituted oligopyridines and triazines in synergy with 2-bromodecanoic acid. (Presented at the International Solvent Extraction Conference, July 1999 in Barcelona)

    International Nuclear Information System (INIS)

    Enarsson, Aa.; Spjuth, L.; Liljenzin, J.O.; Kaellvenius, G.

    2000-01-01

    The separation of trivalent actinides and lanthanides with some substituted oligopyridines and triazines in synergy with 2-bromodecanoic acid was studied. All ligands, except the quinolinyl-derivatives, showed high metal extraction and good separation factors for trivalent actinides over lanthanides. The substituted di-pyridyltriazines and the quaterpyridine showed the highest distribution ratios and quater- and quinquepyridine the highest separation factors, at low nitric acid concentration. The basicity of the different ligands were determined by non-aqueous titration in acetonitrile media and was related to the metal extraction. The substituted di-pyridyltriazines, which showed the highest metal extraction also showed the lowest basicity

  18. Electrochemical characterization of Zr-based thin film metallic glass in hydrochloric aqueous solution

    International Nuclear Information System (INIS)

    Chuang, Ching-Yen; Liao, Yi-Chia; Lee, Jyh-Wei; Li, Chia-Lin; Chu, Jinn P.; Duh, Jenq-Gong

    2013-01-01

    Recently thin film metallic glass represents a class of promising engineering materials for structural applications. In this work, the Zr-based thin film metallic glass (TFMG) was fabricated on the Si and AISI 420 substrates using a Zr–Cu–Ni–Al alloy and pure Zr metal targets by a pulsed DC magnetron sputtering system. The chemical compositions, crystalline structures, microstructures and corrosion behavior in hydrochloric (HCl) aqueous solutions of Zr-based TFMGs were investigated. The results showed that the surface morphologies of Zr-based TFMG were very smooth. A compact and dense structure without columnar structure was observed. The amorphous structure of Zr-based TFMG was characterized by the X-ray diffractometer and transmission electron microscopy analyses. After the potentiodynamic polarization test, the better corrosion resistance was achieved for the Zr-based TFMG coated AISI 420 in 1 mM HCl aqueous solution. Based on the surface morphologies and chemical analysis results of the corroded surfaces, the pitting, crevice corrosion and filiform corrosion were found. The corrosion mechanisms of the Zr-based TFMG were discussed in this work. - Highlights: ► Zr-based thin film metallic glass with amorphous structure. ► Better corrosion resistance of Zr-based thin film metallic glass observed. ► Pitting, crevice and filiform corrosion reactions revealed. ► The Cu-rich corrosion products found in the pit. ► Nanowire and flaky corrosion products formed adjacent to the filiform corrosion path

  19. Separation of cerium from other lanthanides by leaching with nitric acid rare earth(III) hydroxide-cerium(IV) oxide mixtures

    International Nuclear Information System (INIS)

    Mioduski, T.; Dong Anh Hao; Hoang Hong Luan

    1989-01-01

    The objective of the present work is a method for separating Ce from other Ln in the raw natural mixtures of rare earth hydroxides obtained from Vietnamese and Mongolian fluorocarbonate ores. The method, a simple acid digestion, should combine a maximum Ln(III) concentration of the effluent solution with a nitrate counter-ion environment and high selectivity vs. leaching yield parameters. Under optimum conditions Ce (and Th, if present) virtually does not pass into solution while the yield of leaching and the sum of REE oxides concentration in the after-leach solution reach the maximum values of 97% (mass) and 0.18 kg x dm -3 , respectively. (author) 9 refs.; 8 tabs

  20. Separation of Gram-amounts of Lanthanides by Cation Exchange, using an aqueous Solution of α-Hydroxyisobutyric Acid as an Eluant. RCN Report

    International Nuclear Information System (INIS)

    Das, H.A.; Hoede, D.; Stigt, Ch.A. van; Zonderhuis, J.

    1970-09-01

    This report describes a procedure developed for the mutual separation of gram quantities of the lanthanides present in solutions of thermal fission products. A second aim was the purification of ''crude'' 147 Pm-sources. The method is based on column chromatography on Dowex - 50 W (50 - 100 mesh) with an aqueous solution of a-hydroxyisobutyric acid (AHIB) as an eluant. Due to the radioactivity of the samples, the process has to be performed in a shielded glove-box. Consequently, a considerably economy was exercised with respect to the volume of the apparatus. The process was successfully tested with labeled artificial mixtures of 20 grammes of the rare earths involved. The method has been applied to the purification of batches of ''crude'' 147 Pm. (author)