WorldWideScience

Sample records for ceramic membrane enabling

  1. Microporous alumina ceramic membranes

    Science.gov (United States)

    Anderson, Marc A.; Sheng, Guangyao

    1993-01-01

    Several methods are disclosed for the preparation microporous alumina ceramic membranes. For the first time, porous alumina membranes are made which have mean pore sizes less than 100 Angstroms and substantially no pores larger than that size. The methods are based on improved sol-gel techniques.

  2. Supported microporous ceramic membranes

    Science.gov (United States)

    Webster, E.; Anderson, M.

    1993-12-14

    A method for the formation of microporous ceramic membranes onto a porous support includes placing a colloidal suspension of metal or metal oxide particles on one side of the porous support and exposing the other side of the porous support to a drying stream of gas or a reactive gas stream so that the particles are deposited on the drying side of the support as a gel. The gel so deposited can be sintered to form a supported ceramic membrane useful for ultrafiltration, reverse osmosis, or molecular sieving having mean pore sizes less than 100 Angstroms. 4 figures.

  3. Oxygen Transport Ceramic Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay; N. Nagabhushana; Thomas W. Eagar; Harold R. Larson; Raymundo Arroyave; X.-D Zhou; Y.-W. Shin; H.U. Anderson; Nigel Browning; Alan Jacobson; C.A. Mims

    2003-11-01

    The present quarterly report describes some of the initial studies on newer compositions and also includes newer approaches to address various materials issues such as in metal-ceramic sealing. The current quarter's research has also focused on developing a comprehensive reliability model for predicting the structural behavior of the membranes in realistic conditions. In parallel to industry provided compositions, models membranes have been evaluated in varying environment. Of importance is the behavior of flaws and generation of new flaws aiding in fracture. Fracture mechanics parameters such as crack tip stresses are generated to characterize the influence of environment. Room temperature slow crack growth studies have also been initiated in industry provided compositions. The electrical conductivity and defect chemistry of an A site deficient compound (La{sub 0.55}Sr{sub 0.35}FeO{sub 3}) was studied. A higher conductivity was observed for La{sub 0.55}Sr{sub 0.35}FeO{sub 3} than that of La{sub 0.60}Sr{sub 0.40}FeO{sub 3} and La{sub 0.80}Sr{sub 0.20}FeO{sub 3}. Defect chemistry analysis showed that it was primarily contributed by a higher carrier concentration in La{sub 0.55}Sr{sub 0.35}FeO{sub 3}. Moreover, the ability for oxygen vacancy generation is much higher in La{sub 0.55}Sr{sub 0.35}FeO{sub 3} as well, which indicates a lower bonding strength between Fe-O and a possible higher catalytic activity for La{sub 0.55}Sr{sub 0.35}FeO{sub 3}. The program continued to investigate the thermodynamic properties (stability and phase separation behavior) and total conductivity of prototype membrane materials. The data are needed together with the kinetic information to develop a complete model for the membrane transport. Previous report listed initial measurements on a sample of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-x} prepared in-house by Praxair. Subsequently, a second sample of powder from a larger batch of sample were characterized and compared

  4. Gas Separations using Ceramic Membranes

    Energy Technology Data Exchange (ETDEWEB)

    Paul KT Liu

    2005-01-13

    This project has been oriented toward the development of a commercially viable ceramic membrane for high temperature gas separations. A technically and commercially viable high temperature gas separation membrane and process has been developed under this project. The lab and field tests have demonstrated the operational stability, both performance and material, of the gas separation thin film, deposited upon the ceramic membrane developed. This performance reliability is built upon the ceramic membrane developed under this project as a substrate for elevated temperature operation. A comprehensive product development approach has been taken to produce an economically viable ceramic substrate, gas selective thin film and the module required to house the innovative membranes for the elevated temperature operation. Field tests have been performed to demonstrate the technical and commercial viability for (i) energy and water recovery from boiler flue gases, and (ii) hydrogen recovery from refinery waste streams using the membrane/module product developed under this project. Active commercializations effort teaming with key industrial OEMs and end users is currently underway for these applications. In addition, the gas separation membrane developed under this project has demonstrated its economical viability for the CO2 removal from subquality natural gas and landfill gas, although performance stability at the elevated temperature remains to be confirmed in the field.

  5. Enabling Technologies for Ceramic Hot Section Components

    Energy Technology Data Exchange (ETDEWEB)

    Venkat Vedula; Tania Bhatia

    2009-04-30

    Silicon-based ceramics are attractive materials for use in gas turbine engine hot sections due to their high temperature mechanical and physical properties as well as lower density than metals. The advantages of utilizing ceramic hot section components include weight reduction, and improved efficiency as well as enhanced power output and lower emissions as a result of reducing or eliminating cooling. Potential gas turbine ceramic components for industrial, commercial and/or military high temperature turbine applications include combustor liners, vanes, rotors, and shrouds. These components require materials that can withstand high temperatures and pressures for long duration under steam-rich environments. For Navy applications, ceramic hot section components have the potential to increase the operation range. The amount of weight reduced by utilizing a lighter gas turbine can be used to increase fuel storage capacity while a more efficient gas turbine consumes less fuel. Both improvements enable a longer operation range for Navy ships and aircraft. Ceramic hot section components will also be beneficial to the Navy's Growth Joint Strike Fighter (JSF) and VAATE (Versatile Affordable Advanced Turbine Engines) initiatives in terms of reduced weight, cooling air savings, and capability/cost index (CCI). For DOE applications, ceramic hot section components provide an avenue to achieve low emissions while improving efficiency. Combustors made of ceramic material can withstand higher wall temperatures and require less cooling air. Ability of the ceramics to withstand high temperatures enables novel combustor designs that have reduced NO{sub x}, smoke and CO levels. In the turbine section, ceramic vanes and blades do not require sophisticated cooling schemes currently used for metal components. The saved cooling air could be used to further improve efficiency and power output. The objectives of this contract were to develop technologies critical for ceramic hot section

  6. Oxygen Transport Ceramic Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

    2005-05-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped Ti-substituted perovskites, La{sub 0.7}Sr{sub 0.3}Mn{sub 1-x}Ti{sub x}O{sub 3}, with 0 {le} x {le} 0.20, were investigated by neutron diffraction, magnetization, electric resistivity, and magnetoresistance (MR) measurements. All samples show a rhombohedral structure (space group R3C) from 10 K to room temperature. At room temperature, the cell parameters a, c and the unit cell volume increase with increasing Ti content. However, at 10 K, the cell parameter a has a maximum value for x = 0.10, and decreases for x > 0.10, while the unit cell volume remains nearly constant for x > 0.10. The average (Mn,Ti)-O bond length increases up to x = 0.15, and the (Mn,Ti)-O-(Mn,Ti) bond angle decreases with increasing Ti content to its minimum value at x = 0.15 at room temperature. Below the Curie temperature TC, the resistance exhibits metallic behavior for the x {le} 0.05 samples. A metal (semiconductor) to insulator transition is observed for the x {ge} 0.10 samples. A peak in resistivity appears below TC for all samples, and shifts to a lower temperature as x increases. The substitution of Mn by Ti decreases the 2p-3d hybridization between O and Mn ions, reduces the bandwidth W, and increases the electron-phonon coupling. Therefore, the TC shifts to a lower temperature and the resistivity increases with increasing Ti content. A field-induced shift of the resistivity maximum occurs at x {le} 0.10 compounds. The maximum MR effect is about 70% for La{sub 0.7}Sr{sub 0.3}Mn{sub 0.8}Ti{sub 0.2}O{sub 3}. The separation of TC and the resistivity maximum temperature T{sub {rho},max} enhances the MR effect in these compounds due to the weak coupling between the magnetic ordering and the resistivity as compared with La{sub 0.7}Sr{sub 0.3}MnO{sub 3}. The bulk densities of the membranes were determined using the

  7. Oxygen Transport Ceramic Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay; T. Nithyanantham

    2006-06-30

    A non-agglomerated and nanocrystalline-sized powder was successfully produced using ethylene glycol nitrate methods. The LSFT powder prepared using this method exhibits well dispersed and nano-sized particles about 100-200 nm. The density of LSFT sintered at 1300 C was about 90% of the theoretical density at which is 100 C less than that of the previous LSFT which was sintered at 1400 C. The sample sintered at 1400 C exhibited the evidence of a liquid phase at the grain boundaries and 2nd phase formation which probably caused low mechanical stability. The electrical conductivity and Seebeck coefficient were measured as a function of temperature. The LSFT-CGO specimens were cut from the as sintered bars and used for the evaluation of Mechanical Properties after polishing. The effect of strain rate on the flexural strength of the LSFT-CGO test specimens was studied. Three strain rates 6, 60 and 600 {micro}m/ min were chosen for this study. It is observed from the results that with increasing cross head speed the membrane takes higher loads to fail. A reduction in the strength of the membrane was observed at 1000 C in N{sub 2}. Two different routes were investigated to synthesis GDC using either formate or carbonate precursors. The precursor and CGO particle morphologies were examined by scanning electron microscopy. The thermal decomposition behaviors of Ce(Gd)(HCOO){sub 3} and Ce(Gd)(CO{sub 3})(OH) were determined by thermogravimetric analysis (TGA) at a rate of 3 C/min in air. The X-ray powder diffraction patterns of the precursor and CGO were collected and nitrogen adsorption isotherms were measured. Conductivity measurements were made by AC impedance spectroscopy on sintered disks in air using platinum electrodes.

  8. Salt splitting with ceramic membranes

    Energy Technology Data Exchange (ETDEWEB)

    Kurath, D. [Pacific Northwest National Lab., Richland, WA (United States)

    1996-10-01

    The purpose of this task is to develop ceramic membrane technologies for salt splitting of radioactively contaminated sodium salt solutions. This technology has the potential to reduce the low-level waste (LLW) disposal volume, the pH and sodium hydroxide content for subsequent processing steps, the sodium content of interstitial liquid in high-level waste (HLW) sludges, and provide sodium hydroxide free of aluminum for recycle within processing plants at the DOE complex. Potential deployment sites include Hanford, Savannah River, and Idaho National Engineering Laboratory (INEL). The technical approach consists of electrochemical separation of sodium ions from the salt solution using sodium (Na) Super Ion Conductors (NaSICON). As the name implies, sodium ions are transported rapidly through these ceramic crystals even at room temperatures.

  9. Salt splitting using ceramic membranes

    Energy Technology Data Exchange (ETDEWEB)

    Kurath, D.E. [Pacific Northwest National Lab., Richland, WA (United States)

    1997-10-01

    Many radioactive aqueous wastes in the DOE complex have high concentrations of sodium that can negatively affect waste treatment and disposal operations. Sodium can decrease the durability of waste forms such as glass and is the primary contributor to large disposal volumes. Waste treatment processes such as cesium ion exchange, sludge washing, and calcination are made less efficient and more expensive because of the high sodium concentrations. Pacific Northwest National Laboratory (PNNL) and Ceramatec Inc. (Salt Lake City UT) are developing an electrochemical salt splitting process based on inorganic ceramic sodium (Na), super-ionic conductor (NaSICON) membranes that shows promise for mitigating the impact of sodium. In this process, the waste is added to the anode compartment, and an electrical potential is applied to the cell. This drives sodium ions through the membrane, but the membrane rejects most other cations (e.g., Sr{sup +2}, Cs{sup +}). The charge balance in the anode compartment is maintained by generating H{sup +} from the electrolysis of water. The charge balance in the cathode is maintained by generating OH{sup {minus}}, either from the electrolysis of water or from oxygen and water using an oxygen cathode. The normal gaseous products of the electrolysis of water are oxygen at the anode and hydrogen at the cathode. Potentially flammable gas mixtures can be prevented by providing adequate volumes of a sweep gas, using an alternative reductant or destruction of the hydrogen as it is generated. As H{sup +} is generated in the anode compartment, the pH drops. The process may be operated with either an alkaline (pH>12) or an acidic anolyte (pH <1). The benefits of salt splitting using ceramic membranes are (1) waste volume reduction and reduced chemical procurement costs by recycling of NaOH; and (2) direct reduction of sodium in process streams, which enhances subsequent operations such as cesium ion exchange, calcination, and vitrification.

  10. Glass ceramic ZERODUR enabling nanometer precision

    Science.gov (United States)

    Jedamzik, Ralf; Kunisch, Clemens; Nieder, Johannes; Westerhoff, Thomas

    2014-03-01

    The IC Lithography roadmap foresees manufacturing of devices with critical dimension of positioning accuracy requiring sub nanometer position measurement accuracy. The glass ceramic ZERODUR® is a well-established material in critical components of microlithography wafer stepper and offered with an extremely low coefficient of thermal expansion (CTE), the tightest tolerance available on market. SCHOTT is continuously improving manufacturing processes and it's method to measure and characterize the CTE behavior of ZERODUR® to full fill the ever tighter CTE specification for wafer stepper components. In this paper we present the ZERODUR® Lithography Roadmap on the CTE metrology and tolerance. Additionally, simulation calculations based on a physical model are presented predicting the long term CTE behavior of ZERODUR® components to optimize dimensional stability of precision positioning devices. CTE data of several low thermal expansion materials are compared regarding their temperature dependence between - 50°C and + 100°C. ZERODUR® TAILORED 22°C is full filling the tight CTE tolerance of +/- 10 ppb / K within the broadest temperature interval compared to all other materials of this investigation. The data presented in this paper explicitly demonstrates the capability of ZERODUR® to enable the nanometer precision required for future generation of lithography equipment and processes.

  11. SUPPORTED DENSE CERAMIC MEMBRANES FOR OXYGEN SEPARATION

    Energy Technology Data Exchange (ETDEWEB)

    Timothy L. Ward

    2000-06-30

    Mixed-conducting membranes have the ability to conduct oxygen with perfect selectivity at elevated temperatures, which makes them an extremely attractive alternative for oxygen separation and membrane reactor applications. The ability to reliably fabricate these membranes in thin or thick films would enable solid-state divisional limitations to be minimized, thus providing higher oxygen flux. Based on that motivation, the overall objective for this project is to develop and demonstrate a strategy for the fabrication of supported Wick film ceramic mixed conducting membranes, and improve the understanding of the fundamental issues associated with reliable fabrication of these membranes. The project has focused on the mixed-conducting ceramic composition SrCo{sub 0.5}FeO{sub x} because of its superior permeability and stability in reducing atmospheres. The fabrication strategy employed involves the deposition of SrCo{sub 0.5}FeO{sub x} thick films onto porous supports of the same composition. In the second year of this project, we completed characterization of the sintering and phase behavior of the porous SrCo{sub 0.5}FeO{sub x} supports, leading to a standard support fabrication methodology. Using a doctor blade method, pastes made from aerosol-derived SrCo{sub 0.5}FeO{sub x} powder dispersed with polyethylene glycol were applied to the supports, and the sintering behavior of the thick film membranes was examined in air and nitrogen atmospheres. It has been demonstrated that the desired crystalline phase content can be produced in the membranes, and that the material in the membrane layer can be highly densified without densifying the underlying support. However, considerable cracking and opening of the film occurred when films densified to a high extent. The addition of MgO into the SrCo{sub 0.5}FeO{sub x} supports was shown to inhibit support sintering so that temperatures up to 1300 C, where significant liquid formation occurs, could be used for film sintering

  12. Proton conducting ceramic membranes for hydrogen separation

    Science.gov (United States)

    Elangovan, S.; Nair, Balakrishnan G.; Small, Troy; Heck, Brian

    2011-09-06

    A multi-phase proton conducting material comprising a proton-conducting ceramic phase and a stabilizing ceramic phase. Under the presence of a partial pressure gradient of hydrogen across the membrane or under the influence of an electrical potential, a membrane fabricated with this material selectively transports hydrogen ions through the proton conducting phase, which results in ultrahigh purity hydrogen permeation through the membrane. The stabilizing ceramic phase may be substantially structurally and chemically identical to at least one product of a reaction between the proton conducting phase and at least one expected gas under operating conditions of a membrane fabricated using the material. In a barium cerate-based proton conducting membrane, one stabilizing phase is ceria.

  13. Impregnation of ceramic membranes by anatase

    Czech Academy of Sciences Publication Activity Database

    Vacík, M.; Hofman, R.; Mastný, L.; Šrank, Z.; Brožek, Vlastimil

    Praha: MAXDORF,s.r.o, 2004 - (Nitsch, K.; Rodová, M.), s. 64-65 ISBN 80-7345-032-1. [Joint Seminar Development in Material Science Research and Education /14th./. Lednice (CZ), 31.08.2004-03.09.2004] Institutional research plan: CEZ:AV0Z2043910 Keywords : ceramic membranes, anatase impregnation, photocatalytic properties Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass

  14. Reactor process using metal oxide ceramic membranes

    Science.gov (United States)

    Anderson, M.A.

    1994-05-03

    A reaction vessel for use in photoelectrochemical reactions includes as its reactive surface a metal oxide porous ceramic membrane of a catalytic metal such as titanium. The reaction vessel includes a light source and a counter electrode. A provision for applying an electrical bias between the membrane and the counter electrode permits the Fermi levels of potential reaction to be favored so that certain reactions may be favored in the vessel. The electrical biasing is also useful for the cleaning of the catalytic membrane. Also disclosed is a method regenerating a porous metal oxide ceramic membrane used in a photoelectrochemical catalytic process by periodically removing the reactants and regenerating the membrane using a variety of chemical, thermal, and electrical techniques. 2 figures.

  15. Novel, Ceramic Membrane System For Hydrogen Separation

    Energy Technology Data Exchange (ETDEWEB)

    Elangovan, S.

    2012-12-31

    Separation of hydrogen from coal gas represents one of the most promising ways to produce alternative sources of fuel. Ceramatec, teamed with CoorsTek and Sandia National Laboratories has developed materials technology for a pressure driven, high temperature proton-electron mixed conducting membrane system to remove hydrogen from the syngas. This system separates high purity hydrogen and isolates high pressure CO{sub 2} as the retentate, which is amenable to low cost capture and transport to storage sites. The team demonstrated a highly efficient, pressure-driven hydrogen separation membrane to generate high purity hydrogen from syngas using a novel ceramic-ceramic composite membrane. Recognizing the benefits and limitations of present membrane systems, the all-ceramic system has been developed to address the key technical challenges related to materials performance under actual operating conditions, while retaining the advantages of thermal and process compatibility offered by the ceramic membranes. The feasibility of the concept has already been demonstrated at Ceramatec. This project developed advanced materials composition for potential integration with water gas shift rectors to maximize the hydrogenproduction.

  16. Ceramic membranes for high temperature hydrogen separation

    Energy Technology Data Exchange (ETDEWEB)

    Fain, D.E.; Roettger, G.E. [Oak Ridge K-25 Site, TN (United States)

    1996-08-01

    Ceramic gas separation membranes can provide very high separation factors if the pore size is sufficiently small to separate gas molecules by molecular sieving and if oversized pores are adequately limited. Ceramic membranes typically have some pores that are substantially larger than the mean pore size and that should be regarded as defects. To assess the effects of such defects on the performance of ceramic membranes, a simple mathematical model has been developed to describe flow through a gas separation membrane that has a primary mode of flow through very small pores but that has a secondary mode of flow through undesirably large pores. This model permits separation factors to be calculated for a specified gas pair as a function of the molecular weights and molecular diameters of the gases, the membrane pore diameter, and the diameter and number of defects. This model will be described, and key results from the model will be presented. The separation factors of the authors membranes continue to be determined using a permeance test system that measures flows of pure gases through a membrane at temperatures up to 275{degrees}C. A primary goal of this project for FY 1996 is to develop a mixed gas separation system for measuring the separation efficiency of membranes at higher temperatures. Performance criteria have been established for the planned mixed gas separation system and design of the system has been completed. The test system is designed to measure the separation efficiency of membranes at temperatures up to 600{degrees}C and pressures up to 100 psi by separating the constituents of a gas mixture containing hydrogen. The system will accommodate the authors typical experimental membrane that is tubular and has a diameter of about 9 mm and a length of about 23 cm. The design of the new test system and its expected performance will be discussed.

  17. FAS grafted superhydrophobic ceramic membrane

    International Nuclear Information System (INIS)

    The hydrophobic properties of γ-Al2O3 membrane have been obtained by grafting fluoroalkylsilane (FAS) on the surface of the membrane. The following grafting parameters were studied: the eroding time of the original membrane, the grafting time, the concentration of FAS solution and the multiplicity of grafting. Hydrophobicity of the membranes was characterized by contact angle (CA) measurement. The thermogravimetric analysis (TGA) was used to investigate the weight loss process (25-800 deg. C) of the fluoroalkylsilane grafted on Al2O3 powders under different grafting conditions. The morphologies of the membranes modified under different parameters were examined by field emission scanning electron microscopy (FE-SEM) and the surface roughness (Ra) was measured using white light interferometers. A needle-like structure was observed on the membrane surface after modification, which causes the change of Ra. On the results above, we speculated a model to describe the reaction between FAS and γ-Al2O3 membrane surface as well as the formed surface morphology.

  18. Preparation and Chiral Selectivity of BSA-Modified Ceramic Membrane

    Institute of Scientific and Technical Information of China (English)

    Cai Lian SU; Rong Ji DAI; Bin TONG; Yu Lin DENG

    2006-01-01

    An affinity-transport system, containing porous ceramic membranes bound with bovine serum albumin (BSA) was used for chiral separation of racemic tryptophan. The preparation of BSA modified ceramic membrane included three steps. Firstly, the membrane was modified with amino group using silanization with an amino silane. Secondly, the amino group modified membrane was bound with aldehyde group using gluteraldehyde. Finally, BSA was covalently bound on the surface of the ceramic membrane. Efficient separation of racemic tryptophan was carried out by performing permeation cell experiments, with BSA modified, porous ceramic membranes.

  19. Ceramic ultrafiltration membranes with photocatalytic properties

    Science.gov (United States)

    Bell, Deborah Wildman

    The photocatalytic properties of ceramic ultrafilters have been utilized in the development of a novel in-situ membrane cleaning process for ultrafiltration membranes fabricated from titania. The use of the photoactive membrane layer mitigates the effects of foulants in the system, thereby yielding an increase in the observed overall flux without sacrificing rejection of the solute by the membrane. Photocatalytic membranes of titania supported on porous tubes of alpha-alumina were fabricated using sol-gel techniques. These membranes were developed on the basis of the results of two-level factorial experimental designs. Electron microscopy and x-ray spectrometry were employed to evaluate coverage of the support by the membrane, the thickness of the membrane, and the presence of defects in the membrane. The photocatalytic membrane system was characterized to determine both morphological and performance parameters. Morphological parameters included the pore diameters, Darcy coefficients, and the individual resistances associated with each of the porous layers comprising the composite photocatalytic membrane. Performance parameters included the nominal molecular weight cutoff values of the ceramic membranes, the rate of permeation of pure solvent in the presence and the absence of UV illumination through the porous layers of interest, and the ability of the photocatalytic membrane to resist fouling and maintain permselectivity in the presence of UV illumination. The photocatalytic membranes were used to ultrafilter aqueous solutions of polymeric organic foulants present at an initial concentration of 1 x 10-3 M. Formation of a gel layer of foulant on the surface of the membrane was observed in the presence and in the absence of UV radiation; however, the results of permeability experiments indicated that formation of this foulant layer was significantly retarded (by a factor of two) in the presence of UV radiation. Improvement in the flow rate of permeate through the

  20. SUPPORTED DENSE CERAMIC MEMBRANES FOR OXYGEN SEPARATION

    Energy Technology Data Exchange (ETDEWEB)

    Timothy L. Ward

    2003-03-01

    This project addresses the need for reliable fabrication methods of supported thin/thick dense ceramic membranes for oxygen separation. Some ceramic materials that possess mixed conductivity (electronic and ionic) at high temperature have the potential to permeate oxygen with perfect selectivity, making them very attractive for oxygen separation and membrane reactor applications. In order to maximize permeation rates at the lowest possible temperatures, it is desirable to minimize diffusional limitations within the ceramic by reducing the thickness of the ceramic membrane, preferably to thicknesses of 10 {micro}m or thinner. It has proven to be very challenging to reliably fabricate dense, defect-free ceramic membrane layers of such thickness. In this project we are investigating the use of ultrafine SrCo{sub 0.5}FeO{sub x} (SCFO) powders produced by aerosol pyrolysis to fabricate such supported membranes. SrCo{sub 0.5}FeO{sub x} is a ceramic composition that has been shown to have desirable oxygen permeability, as well as good chemical stability in the reducing environments that are encountered in some important applications. Our approach is to use a doctor blade procedure to deposit pastes prepared from the aerosol-derived SCFO powders onto porous SCFO supports. We have previously shown that membrane layers deposited from the aerosol powders can be sintered to high density without densification of the underlying support. However, these membrane layers contained large-scale cracks and open areas, making them unacceptable for membrane purposes. In the past year, we have refined the paste formulations based on guidance from the ceramic tape casting literature. We have identified a multicomponent organic formulation utilizing castor oil as dispersant in a solvent of mineral spirits and isopropanol. Other additives were polyvinylbutyral as binder and dibutylphthalate as plasticizer. The nonaqueous formulation has superior wetting properties with the powder, and

  1. Ceramic nanostructure materials, membranes and composite layers

    OpenAIRE

    Burggraaf, A.J.; Keizer, K.; Hassel, van, E Edwin

    1989-01-01

    Synthesis methods to obtain nanoscale materials will be briefly discussed with a focus on sol-gel methods. Three types of nanoscale composites (powders, membranes and ion implanted layers) will be discussed and exemplified with recent original research results. Ceramic membranes with a thickness of 1–10 μm consist of a packing of elementary particles with a size of 3–7 nm. The mean pore size is about 2.5–3 nm. The preparation routes are based on sol and sol-gel technologies. The pores can be ...

  2. Integrated Ceramic Membrane System for Hydrogen Production

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, Joseph; Lim, Hankwon; Drnevich, Raymond

    2010-08-05

    Phase I was a technoeconomic feasibility study that defined the process scheme for the integrated ceramic membrane system for hydrogen production and determined the plan for Phase II. The hydrogen production system is comprised of an oxygen transport membrane (OTM) and a hydrogen transport membrane (HTM). Two process options were evaluated: 1) Integrated OTM-HTM reactor – in this configuration, the HTM was a ceramic proton conductor operating at temperatures up to 900°C, and 2) Sequential OTM and HTM reactors – in this configuration, the HTM was assumed to be a Pd alloy operating at less than 600°C. The analysis suggested that there are no technical issues related to either system that cannot be managed. The process with the sequential reactors was found to be more efficient, less expensive, and more likely to be commercialized in a shorter time than the single reactor. Therefore, Phase II focused on the sequential reactor system, specifically, the second stage, or the HTM portion. Work on the OTM portion was conducted in a separate program. Phase IIA began in February 2003. Candidate substrate materials and alloys were identified and porous ceramic tubes were produced and coated with Pd. Much effort was made to develop porous substrates with reasonable pore sizes suitable for Pd alloy coating. The second generation of tubes showed some improvement in pore size control, but this was not enough to get a viable membrane. Further improvements were made to the porous ceramic tube manufacturing process. When a support tube was successfully coated, the membrane was tested to determine the hydrogen flux. The results from all these tests were used to update the technoeconomic analysis from Phase I to confirm that the sequential membrane reactor system can potentially be a low-cost hydrogen supply option when using an existing membrane on a larger scale. Phase IIB began in October 2004 and focused on demonstrating an integrated HTM/water gas shift (WGS) reactor to

  3. Ceramic membranes for high temperature hydrogen separation

    Energy Technology Data Exchange (ETDEWEB)

    Adcock, K.D.; Fain, D.E.; James, D.L.; Powell, L.E.; Raj, T.; Roettger, G.E.; Sutton, T.G. [East Tennessee Technology Park, Oak Ridge, TN (United States)

    1997-12-01

    The separative performance of the authors` ceramic membranes has been determined in the past using a permeance test system that measured flows of pure gases through a membrane at temperatures up to 275 C. From these data, the separation factor was determined for a particular gas pair from the ratio of the pure gas specific flows. An important project goal this year has been to build a Mixed Gas Separation System (MGSS) for measuring the separation efficiencies of membranes at higher temperatures and using mixed gases. The MGSS test system has been built, and initial operation has been achieved. The MGSS is capable of measuring the separation efficiency of membranes at temperatures up to 600 C and pressures up to 100 psi using a binary gas mixture such as hydrogen/methane. The mixed gas is fed into a tubular membrane at pressures up to 100 psi, and the membrane separates the feed gas mixture into a permeate stream and a raffinate stream. The test membrane is sealed in a stainless steel holder that is mounted in a split tube furnace to permit membrane separations to be evaluated at temperatures up to 600 C. The compositions of the three gas streams are measured by a gas chromatograph equipped with thermal conductivity detectors. The test system also measures the temperatures and pressures of all three gas streams as well as the flow rate of the feed stream. These data taken over a range of flows and pressures permit the separation efficiency to be determined as a function of the operating conditions. A mathematical model of the separation has been developed that permits the data to be reduced and the separation factor for the membrane to be determined.

  4. SUPPORTED DENSE CERAMIC MEMBRANES FOR OXYGEN SEPARATION

    Energy Technology Data Exchange (ETDEWEB)

    Timothy L. Ward

    2002-07-01

    Mixed-conducting ceramics have the ability to conduct oxygen with perfect selectivity at elevated temperatures, making them extremely attractive as membrane materials for oxygen separation and membrane reactor applications. While the conductivity of these materials can be quite high at elevated temperatures (typically 800-1000 C), much higher oxygen fluxes, or, alternatively, equivalent fluxes at lower temperatures, could be provided by supported thin or thick film membrane layers. Based on that motivation, the objective of this project was to explore the use of ultrafine aerosol-derived powder of a mixed-conducting ceramic material for fabrication of supported thick-film dense membranes. The project focused on the mixed-conducting ceramic composition SrCo{sub 0.5}FeO{sub x} (SCFO) because of the desirable permeability and stability of that material, as reported in the literature. Appropriate conditions to produce the submicron SrCo{sub 0.5}FeO{sub x} powder using aerosol pyrolysis were determined. Porous supports of the same composition were produced by partial sintering of a commercially obtained powder that possessed significantly larger particle size than the aerosol-derived powder. The effects of sintering conditions (temperature, atmosphere) on the porosity and microstructure of the porous discs were studied, and a standard support fabrication procedure was adopted. Subsequently, a variety of paste and slurry formulations were explored utilizing the aerosol-derived SCFO powder. These formulations were applied to the porous SCFO support by a doctor blade or spin coating procedure. Sintering of the supported membrane layer was then conducted, and additional layers were deposited and sintered in some cases. The primary characterization methods were X-ray diffraction and scanning electron microscopy, and room-temperature nitrogen permeation was used to assess defect status of the membranes.We found that non-aqueous paste/slurry formulations incorporating

  5. The synthesis and applications of nano sized ceramic membranes

    International Nuclear Information System (INIS)

    Inorganic membranes composed of particles having sizes below 50 A were produced with oxides of TiO2, ZrO2, and SiO2. This presentation stresses the necessary physical chemical phenomena associated with the particle synthesis and the aggregation behavior of these particles as they are incorporated into the final membrane body. Uses of ceramic membranes in separations, ceramic membrane reactors, and the photocatalytic degradation of organic waste materials are briefly reviewed

  6. Ceramic membrane defouling (cleaning) by air Nano Bubbles.

    Science.gov (United States)

    Ghadimkhani, Aliasghar; Zhang, Wen; Marhaba, Taha

    2016-03-01

    Ceramic membranes are among the most promising technologies for membrane applications, owing to their excellent resistance to mechanical, chemical, and thermal stresses. However, membrane fouling is still an issue that hampers the applications at large scales. Air Nano Bubbles (NBs), due to high mass transfer efficiency, could potentially prevent fouling of ceramic membrane filtration processes. In this study, bench and pilot scale ceramic membrane filtration was performed with air NBs to resist fouling. To simulate fouling, humic acid, as an organic foulant, was applied to the membrane flat sheet surface. Complete membrane clogging was achieved in less than 6 h. Membrane defouling (cleaning) was performed by directly feeding of air NBs to the membrane cells. The surface of the ceramic membrane was superbly cleaned by air NBs, as revealed by atomic force microscope (AFM) images before and after the treatment. The permeate flux recovered to its initial level (e.g., 26.7 × 10(-9) m(3)/m(2)/s at applied pressure of 275.8 kPa), which indicated that NBs successfully unclogged the pores of the membrane. The integrated ceramic membrane and air NBs system holds potential as an innovative sustainable technology. PMID:26741542

  7. Manufacture and optimization of tubular ceramic membrane supports / Hertzog Bissett

    OpenAIRE

    Bissett, Hertzog

    2005-01-01

    Inorganic membranes can be considered an alternative to organic membranes, due to their thermal, chemical and mechanical stability under harsh conditions. Ceramic membranes are used as support structures to increase permeability through composite inorganic membranes in separation processes. Tubular α-alumina membrane supports with smooth inner surfaces can be manufactured by means of the centrifugal casting technique. In this study, the effect of three different AKP powder size...

  8. Nanocomposite Membranes based on Perlfuorosulfonic Acid/Ceramic for Proton Exchange Membrane Fuel Cells

    Institute of Scientific and Technical Information of China (English)

    LI Qiong; WANG Guangjin; YE Hong; YAN Shilin

    2015-01-01

    Perlfuorosulfonic acid/ceramic nanocomposite membranes were investigated as electrolytes for polymer electrolyte membrane fuel cell applications under low relative humidity. Different nanosized ceramics (SiO2, ZrO2, TiO2) with diameters in the range of 2-6 nm were synthesized in situ in Nafion solution through a sol-gel process and the formed nanosized ceramics were well-dispersed in the solution. The nanocomposite membranes were formed through a casting process. The nanocomposite membrane showes enhanced water retention ability and improved proton conductivity compared to those of pure Naifon membrane. The mechanical strength of the formed nanocomposite membranes is slightly less than that of pure Naifon membrane. The experimental results demonstrate that the polymer ceramic nanocompsite membranes are potential electrolyte for fuel cells operating at elevated temperature.

  9. Deashing of coal liquids with ceramic membrane microfiltration and diafiltration

    Energy Technology Data Exchange (ETDEWEB)

    Bishop, B.; Goldsmith, R. [CeraMem Corp., Waltham, MA (United States)

    1995-12-31

    Removal of mineral matter from liquid hydrocarbons derived from the direct liquefaction of coal is required for product acceptability. Current methods include critical solvent deashing (Rose{sup {reg_sign}} process from Kerr-McGee) and filtration (U.S. Filter leaf filter as used by British Coal). These methods produce ash reject streams containing up to 15% of the liquid hydrocarbon product. Consequently, CeraMem proposed the use of low cost, ceramic crossflow membranes for the filtration of coal liquids bottoms to remove mineral matter and subsequent diafiltration (analogous to cake washing in dead-ended filtration) for the removal of coal liquid from the solids stream. The use of these ceramic crossflow membranes overcomes the limitations of traditional polymeric crossflow membranes by having the ability to operate at elevated temperature and to withstand prolonged exposure to hydrocarbon and solvent media. In addition, CeraMem`s membrane filters are significantly less expensive than competitive ceramic membranes due to their unique construction. With these ceramic membrane filters, it may be possible to reduce the product losses associated with traditional deashing processes at an economically attractive cost. The performance of these ceramic membrane microfilters is discussed.

  10. Flux recovery of ceramic tubular membranes fouled with whey proteins: Some aspects of membrane cleaning

    OpenAIRE

    Popović Svetlana S.; Milanović Spasenija D.; Iličić Mirela D.; Lukić Nataša Lj.; Šijački Ivana M.

    2008-01-01

    Efficiency of membrane processes is greatly affected by the flux reduction due to the deposits formation at the surface and/or in the pores of the membrane. Efficiency of membrane processes is affected by cleaning procedure applied to regenerate flux. In this work, flux recovery of ceramic tubular membranes with 50 and 200 nm pore size was investigated. The membranes were fouled with reconstituted whey solution for 1 hour. After that, the membranes were rinsed with clean water and then cleane...

  11. High temperature ceramic membrane reactors for coal liquid upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Tsotsis, T.T.

    1992-06-19

    Ceramic membranes are a new class of materials, which have shown promise in a variety of industrial applications. Their mechanical and chemical stability coupled with a wide range of operating temperatures and pressures make them suitable for environments found in coal liquid upgrading. In this project we will evaluate the performance of Sel-Gel alumina membranes in coal liquid upgrading processes under realistic temperature and pressure conditions and investigate the feasibility of using such membranes in a membrane reactor based coal liquid upgrading process. In addition, the development of novel ceramic membranes with enhanced catalytic activity for coal-liquid upgrading applications, such as carbon-coated alumina membranes, will be also investigated.

  12. PERFORMANCE EVALUATION OF CERAMICS MICROFILTRATION MEMBRANE FOR WATER TREATMENT

    Directory of Open Access Journals (Sweden)

    F.T. Owoeye

    2016-05-01

    Full Text Available Ceramic membranes are especially suitable for processes with high temperatures and harsh chemical environments or for processes where sterilizability of the membrane is important. The main objective of this work is to determine the evaluation of four different ceramic membranes with different material compositions. Ceramic disc type microfiltration membranes were fabricated by the mould and press method from different percentage compositions of clay, kaolin, sawdust and wood charcoal. The fabricated membranes were sintered at a temperature of 1100°C and characterized by an X-ray diffractometer and optical scanner. Compressibility tests and physical properties of the membranes were also examined. It was observed that, as the percentage composition of kaolin increased from 0 to 80% and the percentage composition of clay decreased from 80 to 0% respectively, the compressive stress of all the sample membranes increased, with an increase in compressive strain from 1.8 to 2.4. Sample A had the highest value of compressive stress from 1.8 to 2.2 compressive strain, but sample B had the highest value of compressive stress of 150MPa at a compressive strain of 2.4. Optical micrographs of all membranes showed the presence of uniformly distributed pores and no cracks were seen around them. It was concluded that, with increasing percentage of kaolin and decreasing percentage of clay, there was a decrease in porosity and water absorption, as well as a decrease in the mechanical properties of the fabricated membranes.

  13. High temperature ceramic membrane reactors for coal liquid upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Tsotsis, T.T.

    1992-01-01

    In this project we intend to study a novel process concept, i.e, the use of ceramic membranes reactors in upgrading of coal derived liquids. Membrane reactors have been used in a number of catalytic reaction processes in order to overcome the limitations on conversion imposed by thermodynamic equilibrium. They have, furthermore, the inherent capability for combining reaction and separation in a single step. Thus they offer promise for improving and optimizing yield, selectivity and performance of processes involving complex liquids, as those typically found in coal liquid upgrading. Ceramic membranes are a new class of materials, which have shown promise in a variety of industrial applications. Their mechanical and chemical stability coupled with a wide range of operating temperatures and pressures make them suitable for environments found in coal liquid upgrading. In this project we will evaluate the performance of Sol-Gel alumina membranes in coal liquid upgrading processes under realistic temperature and pressure conditions and investigate the feasibility of using such membranes in a membrane reactor based coal liquid upgrading process. In addition, the development of novel ceramic membranes with enhanced catalytic activity for coal-liquid upgrading applications, such as carbon-coated alumina membranes, will be also investigated.

  14. Fabrication of Ceramic Membrane Chromatography for Biologics Purification

    Directory of Open Access Journals (Sweden)

    Maizirwan Mel

    2011-12-01

    Full Text Available Chromatography is one of the most important separation processes of choice for the recovery/purification of proteins and complex bio-structures. Fabrication of chromatographic membranes and their efficiency in the chromatography process has been the subject of many recent researches. In this study, a coin-like, 13 mm diameter and 3 mm thick, ceramic membrane was fabricated to be used as a chromatographic medium. The membrane is used to replace the conventional resin-based chromatography columns. Hydroxyapatite (HA powder was used as a material for the membrane fabrication. In this project, a HA powder was produced using starch as pore creating agents. Characterization processes were done for the ceramic membrane using the suitable apparatuses. Three parameters of the fabrication process (starch wt %, compaction pressure and sintering temperature were manipulated to optimize the performance of the membrane. The fabricated membrane was placed in a (FPLC system to be tested for its performance as an adsorptive membrane. (IMAC process was run by immobilizing Ni2+ ions at the membrane particles surfaces. NP protein of the (NDV was used to test the membrane's ability to bind Histidine-tagged proteins. The optimum set of process parameters that yielded in the highest porosity and good chromatogram was determined to be 5 wt % starch, 3000 psi compaction pressure and 1100°C sintering temperature.ABSTRAK: Kromatografi merupakan satu daripada proses pengasingan yang penting yang dipilih untuk perolehan/penapisan protein dan biostruktur yang kompleks. Pemfabrikatan membran kromatografi dan kecekapannya dalam proses kromatografi merupakan fokus beberapa kajian terkini. Dalam kajian ini, membran seramik berbentuk duit syiling, berdiameter 13 mm dengan ketebalan 3 mm, direka untuk digunakan sebagai perantara kromatografi. Membran ini digunakan untuk menggantikan turus kromatografi berasaskan resin yang lazim. Serbuk hidroksiapatit (HA digunakan sebagai bahan

  15. Multilayer Membranes Based on Ceramic Materials—Sol-gel Synthesis, Characterization and Membrane Performance

    Institute of Scientific and Technical Information of China (English)

    Sun Qianyao; Xu Chunming

    2007-01-01

    In nearly all chemical and petrochemical systems, separation of products generally accounts for more than 50% of the capital cost and the greatest part of the energy consumption. It is generally believed that membrane systems can offer benefits in both reducing the energy consumption of the separation stages and lowering the capital expenditure (CAPEX). Microporous ceramic membranes have the potential to overcome the limitation in polymer membranes operation, which has been the subject of a large amount of research worldwide in the last two decades. And most of the research has aimed at the production of the asymmetric multilayered membrane based on amorphous oxides by sol-gel techniques. The paper is to give an overview of publications on ceramic membranes, including less common materials of titania, zirconia, which can be used for pervaporation in corrosive media. Commercially available microporous membranes based on these membrane materials and the membrane economics are also summarized.

  16. Deposition and consolidation of porous ceramic films for membrane separation

    DEFF Research Database (Denmark)

    Elmøe, Tobias Dokkedal; Tricoli, Antonio; Johannessen, Tue;

    The deposition of porous ceramic films for membrane separation can be done by several processes such as thermophoresis [1], dip-coating [2] and spray pyrolysis [3]. Here we present a high-speed method, in which ceramic nano-particles form a porous film by filtration on top of a porous ceramic.......E., Sahm, T., Gurlo, A., Barsan, N., Weimar, U., Sensors and Actuators B, 114, 283-295, 2006 [2] Cini, P., Blaha, S.R., Harold, M.P., Venkataraman, K., J. Membrane Sci., 55, 199-225, 1991 [3] Stoermer, A.O., Rupp, J.L.M., Gauckler, L.J., Solid State Ionics, In press, 2006 [4] Andersen, S.K., Johannessen, T...

  17. Inorganic polymer-derived ceramic membranes

    Energy Technology Data Exchange (ETDEWEB)

    Brinker, C.J.; Sehgal, R.; Raman, N.; Schunk, P.R.; Headley, T.J.

    1993-12-31

    Polymeric silica sols were used to prepare membranes on commercial {gamma}-A1{sub 2}O{sub 3} supports. Aging of the silica sols was shown to be effective to form discrete membrane layers. He/N{sub 2} selectivity factors exceeding ideal Knudsen values were observed when the sols were prepared under conditions in which the condensation rate was minimized. It is proposed that the average pore size of the membrane depends on the balance of capillary pressure and modulus during membrane deposition and that the breadth of the pore size distribution might be influenced by the extent of condensation accompanying membrane deposition. The use of organic templates may allow independent control of pore size, pore shape, and pore volume. The membranes are to be used in processing natural gas (gas separation/purification).

  18. Hydrophilic Fe2O3 dynamic membrane mitigating fouling of support ceramic membrane in ultrafiltration of oil/water emulsion

    KAUST Repository

    Lu, Dongwei

    2016-03-17

    Oil/water (O/W) emulsion is daily produced and difficult to be treated effectively. Ceramic membrane ultrafiltration is one of reliable processes for the treatment of O/W emulsion, yet still hindered by membrane fouling. In this study, two types of Fe2O3 dynamic membranes (i.e., pre-coated dynamic membrane and self-forming dynamic membrane) were prepared to mitigate the fouling of support ceramic membrane in O/W emulsion treatment. Pre-coated dynamic membrane (DM) significantly reduced the fouling of ceramic membrane (i.e., 10% increase of flux recovery rate), while self-forming dynamic membrane aggravated ceramic membrane fouling (i.e., 8.6% decrease of flux recovery rate) after four filtration cycles. A possible fouling mechanism was proposed to explain this phenomenon, which was then confirmed by optical images of fouled membranes and the analysis of COD rejection. In addition, the cleaning efficiency of composite membranes (i.e., Fe2O3 dynamic membrane and support ceramic membrane) was enhanced by substitution of alkalescent water backwash for deionized water backwash. The possible reason for this enhancement was also explained. Our result suggests that pre-coated Fe2O3 dynamic membrane with alkalescent water backwash can be a promising technology to reduce the fouling of ceramic membrane and enhance membrane cleaning efficiency in the treatment of oily wastewater.

  19. Electroviscous Effects in Ceramic Nanofiltration Membranes.

    Science.gov (United States)

    Farsi, Ali; Boffa, Vittorio; Christensen, Morten Lykkegaard

    2015-11-16

    Membrane permeability and salt rejection of a γ-alumina nanofiltration membrane were studied and modeled for different salt solutions. Salt rejection was predicted by using the Donnan-steric pore model, in which the extended Nernst-Planck equation was applied to predict ion transport through the pores. The solvent flux was modeled by using the Hagen-Poiseuille equation by introducing electroviscosity instead of bulk viscosity. γ-Alumina particles were used for ζ-potential measurements. The ζ-potential measurements show that monovalent ions did not adsorb on the γ-alumina surface, whereas divalent ions were highly adsorbed. Thus, for divalent ions, the model was modified, owing to pore shrinkage caused by ion adsorption. The ζ-potential lowered the membrane permeability, especially for membranes with a pore radius lower than 3 nm, a ζ-potential higher than 20 mV, and an ionic strength lower than 0.01 m. The rejection model showed that, for a pore radius lower than 3 nm and for solutions with ionic strengths lower than 0.01 m, there is an optimum ζ-potential for rejection, because of the concurrent effects of electromigration and convection. Hence, the model can be used as a prediction tool to optimize membrane perm-selectivity by designing a specific pore size and surface charge for application at specific ionic strengths and pH levels. PMID:26346603

  20. High temperature ceramic membrane reactors for coal liquid upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Tsotsis, T.T.

    1992-01-01

    In this project we will study a novel process concept, i.e., the use of ceramic membrane reactors in upgrading of coal model compounds and coal derived liquids. In general terms, the USC research team is responsible for constructing and operating the membrane reactor apparatus and for testing various inorganic membranes for the upgrading of coal derived asphaltenes and coal model compounds. The USC effort will involve the principal investigator of this project and two graduate research assistants. The ALCOA team is responsible for the preparation of the inorganic membranes, for construction and testing of the ceramic membrane modules, and for measurement of their transport properties. The ALCOA research effort will involve Dr. Paul K. T. Liu, who is the project manager of the ALCOA research team, an engineer and a technician. UNOCAL's contribution will be limited to overall technical assistance in catalyst preparation and the operation of the laboratory upgrading membrane reactor and for analytical back-up and expertise in oil analysis and materials characterization. UNOCAL is a no-cost contractor but will be involved in all aspects of the project, as deemed appropriate.

  1. Flame assisted synthesis of catalytic ceramic membranes

    DEFF Research Database (Denmark)

    Johansen, Johnny; Mosleh, Majid; Johannessen, Tue;

    2004-01-01

    Membranes consisting of one or more metal oxides can be synthesized by flame pyrolysis. The general principle behind flame pyrolysis is the decomposition and oxidation of evaporated organo-metallic precursors in a flame, thereby forming metal oxide monomers. Because of the extreme supersaturation...

  2. Synthesis and characterization of ceramic membranes for micro filtration

    International Nuclear Information System (INIS)

    This paper presents the results of a preliminary research work in the development of ceramic membranes by moulding process. The two major objectives were to determine the effect of operating parameters ori- the membrane sheet and membrane characterization. The starting material for the membrane was powdered aluminum oxide and alumina granules. Alumina granules were obtained by spray drying of mixture of alumina with additives and binders under specific conditions. The membrane sheet was produced by mould pressing at various pressures and then sintering at different temperatures. Membrane characterization was done based on microstructure using SEM, pore size distribution, density, and porosity. Strong and porous membranes were produced at pressing force of 120 -140 kN and sintering temperature of 1400 -1500 'C. Pore size and porosity obtained was in the range of 2 -10 μ m, and 13 - 48% respectively. These membranes can be used for, microfiltration at elevated temperature and under extreme environmental condition. They can also be used as porous support for the production qf composite asymmetric UF/hyperfiltration, and gas separation membranes. Further work in the refinement of' pore-size and permeation studies is envisaged

  3. Synthesis of nanosized powders for preparing ceramic membranes

    International Nuclear Information System (INIS)

    Magnesium-stabilized zirconia have been synthesized by a chemical route. The aim of this work is to obtain powders with suitable chemical and physical properties to be used as ceramic membranes for nanofiltration. The coprecipitation technique with an azeotropic distillation step has been employed for this purpose. Several powder characterization techniques have been utilized. The main results show that nanosized powders with high a degree of purity, high chemical homogeneity and elevated reactivity have been obtained. (orig.)

  4. Sorption Ceramic Membranes with a Functionalized Surface Layer

    Czech Academy of Sciences Publication Activity Database

    Zub, Yu.L.; Tomina, V.V.; Melnyk, I.V.; Stolyarchuk, N.V.; Nazarchuk, H.I.; Sliesarenko, V.V. (ed.); Sliesarenko, V.M.; Topka, Pavel; Šolcová, Olga

    Prague : Orgit, 2014, s. 39. ISBN 978-80-02-02555-9. [International Congress of Chemical and Process Engineering /21./ - CHISA 2014 and Conference on Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction /17./ - PRES 2014. Prague (CZ), 23.08.2014-27.08.2014] Grant ostatní: NATO(US) SPP984398 Institutional support: RVO:67985858 Keywords : ceramic membranes * polysiloxane * layers Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  5. Progress on Porous Ceramic Membrane Reactors for Heterogeneous Catalysis over Ultrafine and Nano-sized Catalysts

    Institute of Scientific and Technical Information of China (English)

    JIANG Hong; MENG Lie; CHEN Rizhi; JIN Wanqin; XING Weihong; XU Nanping

    2013-01-01

    Heterogeneous catalysts with ultrafine or nano particle size have currently attracted considerable attentions in the chemical and petrochemical production processes,but their large-scale applications remain challenging because of difficulties associated with their efficient separation from the reaction slurry.A porous ceramic membrane reactor has emerged as a promising method to solve the problem concerning catalysts separation in situ from the reaction mixture and make the production process continuous in heterogeneous catalysis.This article presents a review of the present progress on porous ceramic membrane reactors for heterogeneous catalysis,which covers classification of configurations of porous ceramic membrane reactor,major considerations and some important industrial applications.A special emphasis is paid to major considerations in term of application-oriented ceramic membrane design,optimization of ceramic membrane reactor performance and membrane fouling mechanism.Finally,brief concluding remarks on porous ceramic membrane reactors are given and possible future research interests are also outlined.

  6. CERAMIC MEMBRANES FOR HYDROGEN PRODUCTION FROM COAL

    Energy Technology Data Exchange (ETDEWEB)

    George R. Gavalas

    2001-11-27

    The present project is devoted to developing hydrogen permselective silica membranes supported on composite supports to achieve high flux and selectivity. The supports consist of a thin zeolite silicalite layer coated on {alpha}-Al{sub 2}O{sub 3} tubes of mean pore size 1 {micro}m. The zeolite layer is grown by reaction in a suitable silicate solution at 95 C. After two or three reaction periods a layer of silicalite crystals about 20 {micro}m thick grows inside the pores of alumina. In addition to the zeolitic pores, this layer contains voids of a few nanometer diameter that remain between the crystals or between the crystals and the pore walls. The quality of the silicalite/alumina composites was evaluated by gas permeation measurements and by nitrogen adsorption and it was found that the residual voids were below 5 nm in diameter. Three techniques were investigated for chemical vapor deposition (CVD) of the silica layer on the silicalite/alumina composite support. The first was TEOS pyrolysis at approximately one millibar partial pressure and 650 C. After 8 h reaction the fluxes of hydrogen and nitrogen at ambient temperature had declined by a factor of approximately 100 indicating sealing of defects and zeolitic pores alike. The second CVD technique investigated was SiCl{sub 4} hydrolysis at 90 C. Deposition in this case was conducted in a series of cycles, each cycle comprising two half reactions, i.e. exposure to SiCl{sub 4} followed by exposure to water vapor. The deposition was interrupted every five cycles to measure the permeation properties of the nascent membrane at 120 C. After a few cycles the membrane pores were sealed, but the silica layer was not thermally stable when the temperature was raised to 400 C. In the third technique investigated, silica deposition was carried out by SiCl{sub 4} hydrolysis at 400 C, again in a sequence of half reaction cycles. After 15 cycles the membrane pores were well sealed by a layer stable to at least 400 C.

  7. Ceramic membranes for gas separation in advanced fossil power plants

    Energy Technology Data Exchange (ETDEWEB)

    Meulenberg, W.A.; Baumann, S.; Ivanova, M.; Gestel, T. van; Bram, M.; Stoever, D. [Forschungszentrum Juelich GmbH (DE). Inst. fuer Energieforschung (IEF)

    2010-07-01

    The reduction or elimination of CO{sub 2} emissions from electricity generation power plants fuelled by coal or gas is a major target in the current socio-economic, environmental and political discussion to reduce green house gas emissions such as CO{sub 2}. This mission can be achieved by introducing gas separation techniques making use of membrane technology, which is, as a rule, associated with significantly lower efficiency losses compared with the conventional separation technologies. Depending on the kind of power plant process different membrane types (ceramic, polymer, metal) can be implemented. The possible technology routes are currently investigated to achieve the emission reduction. They rely on different separation tasks. The CO{sub 2}/N{sub 2} separation is the main target in the post-combustion process. Air separation (O{sub 2}/N{sub 2}) is the focus of the oxyfuel process. In the pre-combustion process an additional H{sub 2}/CO{sub 2} separation is included. Although all separation concepts imply different process requirements they have in common a need in membranes with high permeability, selectivity and stability. In each case CO{sub 2} is obtained in a readily condensable form. CO{sub 2}/N{sub 2} separation membranes like microporous membranes or polymer membranes are applicable in post-combustion stages. In processes with oxyfuel combustion, where the fuel is combusted with pure oxygen, oxygen transport membranes i.e. mixed ionic electronic conducting (MIEC) membranes with mainly perovskite or fluorite structure can be integrated. In the pre-combustion stages of the power plant process, H{sub 2}/CO{sub 2} separation membranes like microporous membranes e.g. doped silica or mixed protonic electronic conductors or metal membranes can be applied. The paper gives an overview about the considered ceramic materials for the different gas separation membranes. The manufacturing of bulk materials as well as supported thin films of these membranes along

  8. Ceramic membrane separation technique for washing nano-sized ceramic powder precursors

    Institute of Scientific and Technical Information of China (English)

    Qiang Dong; Xingqin Liu; Tianshu Zhang

    2011-01-01

    Washing using ceramic micro-filtration membranes was studied in the preparation of nano-sized TiO2 and Al203 powder precursors obtained by wet chemical methods.The key parameters for the washing process,such as operation pressure,cross-flow velocity,and slurry concentration,were examined and optimized.The shape and size of particles influenced the structure of the filter cake,leading to different permeation flux for different systems.The results demonstrated that washing using ceramic membranes is superior to the traditional plate-and-frame filtration and could be considered an advanced technique for ultra-fine powder preparation by wet-chemical method.

  9. Residual stress and fracture of laminated ceramic membranes

    International Nuclear Information System (INIS)

    Bilayer laminated ceramic membranes were produced comprising a layer of gadolinia-doped ceria (CGO) 180 microm thick and a layer of yttria-stabilized zirconia (YSZ) 5 microm thick. The residual stresses in the laminates at room temperature were estimated from their curvature and the elastic constants of the individual layers. The fracture of the laminates was studied in biaxial flexure at 35 and 800 C. The mean failure stress in the CGO in the laminates was much greater than in unlaminated CGO. This is due partly to an improved microstructure from the lamination process and partly to the restraint of the compressively stressed YSZ. The combined effects of higher failure stress and residual stresses lead to the laminated membranes having higher apparent strength than single layer CGO membranes by factors of between 1.75 and 4.06

  10. Hydrogen production from methane using oxygen-permeable ceramic membranes

    Science.gov (United States)

    Faraji, Sedigheh

    Non-porous ceramic membranes with mixed ionic and electronic conductivity have received significant interest in membrane reactor systems for the conversion of methane and higher hydrocarbons to higher value products like hydrogen. However, hydrogen generation by this method has not yet been commercialized and suffers from low membrane stability, low membrane oxygen flux, high membrane fabrication costs, and high reaction temperature requirements. In this dissertation, hydrogen production from methane on two different types of ceramic membranes (dense SFC and BSCF) has been investigated. The focus of this research was on the effects of different parameters to improve hydrogen production in a membrane reactor. These parameters included operating temperature, type of catalyst, membrane material, membrane thickness, membrane preparation pH, and feed ratio. The role of the membrane in the conversion of methane and the interaction with a Pt/CeZrO2 catalyst has been studied. Pulse studies of reactants and products over physical mixtures of crushed membrane material and catalyst have clearly demonstrated that a synergy exists between the membrane and the catalyst under reaction conditions. The degree of catalyst/membrane interaction strongly impacts the conversion of methane and the catalyst performance. During thermogravimetric analysis, the onset temperature of oxygen release for BSCF was observed to be lower than that for SFC while the amount of oxygen release was significantly greater. Pulse injections of CO2 over crushed membranes at 800°C have shown more CO2 dissociation on the BSCF membrane than the SFC membrane, resulting in higher CO formation on the BSCF membrane. Similar to the CO2 pulses, when CO was injected on the samples at 800°C, CO2 production was higher on BSCF than SFC. It was found that hydrogen consumption on BSCF particles is 24 times higher than that on SFC particles. Furthermore, Raman spectroscopy and temperature programmed desorption studies of

  11. Support influence on the properties of the alumina ceramic membranes

    International Nuclear Information System (INIS)

    The ceramic substrates used as supports for the formation of a top layer membrane must meet several requirements.Some of them are: have an average pore size and a suitable surface rugosity to obtain a homogenous top layer preventing the penetration of the membrane precursor particles into the support pores.This work analyzes the performance of the three α-Al2O3 supports, with different average pore sizes and surface textures, for the formation of a membrane top layer by the dipcoating technique from colloids in suspension of aluminum basic acetate and later thermal treatment at 1000degC.The pore size distribution of the supports, the support-membrane systems and the top layer membrane was obtained by the mercury intrusion porosimetry technique.The microstructural differences of the supports and the top layer thickness were observed by MEB.It could be observed that for numerous deposits the membrane layer pore size obtained is independent on the support used and that the thickness of the last layer is lower for the greater pore size supports.The possibility of an intermediate layer between the support and the top layer was considered in every case

  12. Quasi-solid polymer-in-ceramic membrane for Li-ion batteries

    International Nuclear Information System (INIS)

    Highlights: •Novel composite polymer-in-ceramic membrane. •Conformal coating of electrode surface. •Improved electrochemical performance. -- Abstract: The method of electrophoretic deposition (EPD) was used to fabricate ion-conducting polymer-in-ceramic membranes. TGA, DSC, XRD, TOFSIMS, ESEM and AC-impedance tests were used for the characterization of the films. We found that the relative content of polyethylene oxide and LiAlO2 in the membrane depends on the type of solvent and composition of the suspension. Films deposited at 50 V are smoother, conformal and more uniform than those prepared at 100, 150 and 200 V. TOFSIMS positive-ion-species images showed that with increase in concentration of ceramic powder in the suspension, the deposition of PEO occurs predominantly between the LiAlO2 particles. The ionic conductivity of a composite membrane, with impregnated 0.3 M LiTFSI–PYR14TFSI ionic-liquid electrolyte is 1–3 mS/cm at 30–60 °C and comparable to that of commercial battery separators. The conductivity of quasi-solid plasticized PEO-in-LiAlO2 electrolyte is 0.2 mS/cm at room temperature and does not change up to 100 °C. When deposited on a Si anode the membrane conformally follows the contours of the rough electrode surface and provides strong mechanical integrity to the anode, enabling improved capacity of the Li/Si cell. This study paves the way for the application of a new simple EPD approach to the preparation of wide-temperature-range quasi-solid lithium-ion conducting electrolytes

  13. Controlled ceramic porosity and membrane fabrication via alumoxane nanoparticles

    Science.gov (United States)

    Jones, Christopher Daniel

    Carboxylate-alumoxanes, [Al(O)x(OH)y(O2CR) z]n, are organic substituted alumina nano-particles synthesized from boehmite in aqueous solution which are an inexpensive and environmentally-benign precursor for the fabrication of aluminum based ceramic bodies. The carboxylate-ligand on the alumoxane determines the morphology and the porosity of the derived alumina. Investigations of A-, MA-, MEA-, and MEEA-alumoxanes, were undertaken to determine the effects of these organic peripheries on the properties of the alumina at different sintering temperatures including the morphology, surface area, pore volume, pore size, pore size distribution, and crystal phase. The effects of physically or chemically mixing different carboxylate-alumoxanes were also investigated. The alumina derived from the thermolysis of the carboxylate-alumoxanes exhibits small pore diameters and narrow pore size distributions that are desirable for use in ceramic ultrafiltration membranes. In addition, it is possible to form alumina membranes with a range of pore sizes and porosity by changing the organic periphery. This lead to investigating the ability to produce asymmetric alumina filters with characteristics that at the lower end of the ultrafiltration range. The flux, permeability, molecular weight cut-off, roughness, and wettability of the asymmetric alumina membranes derived from carboxylate-alumoxanes are determined. Comparisons of these filters are made with commercially available filters. The ability to dope carboxylate-alumoxanes via a transmetallation reaction followed by thermolysis has previously shown to result in catalytically active alumina based materials. This lead to investigations into forming catalytically active membranes. Dip-coating aqueous solutions of the doped carboxylate-alumoxanes onto porous alumina supports, followed by thermolysis, resulted in the formation of doped-alumina asymmetric filters. In addition, a novel method to form surface-modified carboxylate

  14. Highly efficient hydrophobic titania ceramic membranes for water desalination.

    Science.gov (United States)

    Kujawa, Joanna; Cerneaux, Sophie; Koter, Stanisław; Kujawski, Wojciech

    2014-08-27

    Hydrophobic titania ceramic membranes (300 kD) were prepared by grafting of C6F13C2H4Si(OC2H5)3 and C12F25C2H4Si(OC2H5)3 molecules and thus applied in membrane distillation (MD) process of NaCl solutions. Grafting efficiency and hydrophobicity were evaluated by contact angle measurement, atomic force microscopy, scanning electron microscopy, nitrogen adsorption/desorption, and liquid entry pressure measurement of water. Desalination of NaCl solutions was performed using the modified hydrophobic membranes in air gap MD (AGMD) and direct contact MD (DCMD) processes in various operating conditions. High values of NaCl retention coefficient (>99%) were reached. The permeate fluxes were in the range 231-3692 g·h(-1)·m(-2), depending on applied experimental conditions. AGMD mode appeared to be more efficient showing higher fluxes and selectivity in desalination. Overall mass transfer coefficients (K) for membranes tested in AGMD were constant over the investigated temperature range. However, K values in DCMD increased at elevated temperature. The hydrophobic layer was also stable after 4 years of exposure to open air. PMID:25084346

  15. Flux recovery of ceramic tubular membranes fouled with whey proteins: Some aspects of membrane cleaning

    Directory of Open Access Journals (Sweden)

    Popović Svetlana S.

    2008-01-01

    Full Text Available Efficiency of membrane processes is greatly affected by the flux reduction due to the deposits formation at the surface and/or in the pores of the membrane. Efficiency of membrane processes is affected by cleaning procedure applied to regenerate flux. In this work, flux recovery of ceramic tubular membranes with 50 and 200 nm pore size was investigated. The membranes were fouled with reconstituted whey solution for 1 hour. After that, the membranes were rinsed with clean water and then cleaned with sodium hydroxide solutions or formulated detergents (combination of P3 Ultrasil 67 and P3 Ultrasil 69. Flux recovery after the rinsing step was not satisfactory although fouling resistance reduction was significant so that chemical cleaning was necessary. In the case of 50 nm membrane total flux recovery was achieved after cleaning with 1.0% (w/w sodium hydroxide solution. In the case of 200 nm membrane total flux recovery was not achieved irrespective of the cleaning agent choice and concentration. Cleaning with commercial detergent was less efficient than cleaning with the sodium hydroxide solution.

  16. Porous ceramic membranes: suspension processing, mechanical and transport properties, and application in the osmotic tensiometer

    OpenAIRE

    Biesheuvel, Pieter Maarten

    2000-01-01

    Synthetic membranes are increasingly used for energy-efficient separation of liquid and gaseous mixtures in household applications, environmental technology and the chemical and energy industry. Besides, membranes are used in component-specific sensors in gas and liquid streams, preferably combined with micro-electronic devices. Ceramic membranes have a large potential over their polymer counterparts for applications at high temperature, pressure and in aggressive environments. Ceramic membra...

  17. Silicon nitride coating on titanium to enable titanium-ceramic bonding.

    Science.gov (United States)

    Wang, R R; Welsch, G E; Monteiro, O

    1999-08-01

    Failures that occur in titanium-ceramic restorations are of concern to clinicians. The formation of poorly adhering oxide on titanium at dental porcelain sintering temperatures causes adherence problems between titanium and porcelain, which is the main limiting factor in the fabrication of titanium-ceramic restorations. To overcome this problem a 1-microm thick Si3N4 coating was applied to a titanium surface using a plasma-immersion implantation and deposition method. Such a coating serves as an oxygen diffusion barrier on titanium during the porcelain firings. The protective coating was characterized in the as-deposited condition and after thermal cycling. Cross sections of Ti/Si3N4-porcelain interface regions were examined by various electron microscopy methods and by energy dispersive analysis of X-rays to study the Si3N4 film's effectiveness in preventing titanium oxidation and in forming a bond with porcelain. The experiments have shown that this Si3N4 coating enables significant improvement in Ti-ceramic bonding. PMID:10380005

  18. Ozonation and/or Coagulation - Ceramic Membrane Hybrid for Filtration of Impaired-Quality Source Waters

    KAUST Repository

    Ha, Changwon

    2013-09-01

    When microfiltration (MF) and ultrafiltration (UF) membranes are applied for drinking water treatment/wastewater reuse, membrane fouling is an evitable problem, causing the loss of productivity over time. Polymeric membranes have been often reported to experience rapid and/or problematical fouling, restraining sustainable operation. Ceramic membranes can be effectively employed to treat impaired-quality source waters due to their inherent robustness in terms of physical and chemical stability. This research aimed to identify the effects of coagulation and/or ozonation on ceramic membrane filtration for seawater and wastewater (WW) effluent. Two different types of MF and UF ceramic membranes obtained by sintering (i.e., TAMI made of TiO2+ZrO2) and anodic oxidation process (i.e., AAO made of Al2O3) were employed for bench-scale tests. Precoagulation was shown to play an important role in both enhancing membrane filterability and natural organic matter (NOM) removal efficacy for treating a highorganic surface water. The most critical factors were found to be pH and coagulant dosage with the highest efficiency resulting under low pH and high coagulant dose. Due to the ozone-resistance nature of the ceramic membranes, preozonation allowed the ceramic membranes to be operated at higher flux, especially leading to significant flux improvement when treating seawater in the presence of calcium and magnesium. 4 Dissolved ozone in contact with the TAMI ceramic membrane surface accelerated the formation of hydroxyl (˙OH) radicals in WW effluent treatment. Flux restoration of both ceramic membranes, fouled with seawater and WW effluent, was efficiently achieved by high backwash (BW) pressure and ozone in chemically enhanced backwashing (CEB). Ceramic membranes exhibited a pH-dependent permeate flux while filtering WW effluent, showing reduced fouling with increased pH. On the other hand, for filtering seawater, differences in permeate flux between the two membranes was

  19. Preconceptual design of a salt splitting process using ceramic membranes

    Energy Technology Data Exchange (ETDEWEB)

    Kurath, D.E.; Brooks, K.P.; Hollenberg, G.W.; Clemmer, R. [Pacific Northwest National Lab., Richland, WA (United States); Balagopal, S.; Landro, T.; Sutija, D.P. [Ceramatec, Inc., Salt Lake City, UT (United States)

    1997-01-01

    Inorganic ceramic membranes for salt splitting of radioactively contaminated sodium salt solutions are being developed for treating U. S. Department of Energy tank wastes. The process consists of electrochemical separation of sodium ions from the salt solution using sodium (Na) Super Ion Conductors (NaSICON) membranes. The primary NaSICON compositions being investigated are based on rare- earth ions (RE-NaSICON). Potential applications include: caustic recycling for sludge leaching, regenerating ion exchange resins, inhibiting corrosion in carbon-steel tanks, or retrieving tank wastes; reducing the volume of low-level wastes volume to be disposed of; adjusting pH and reducing competing cations to enhance cesium ion exchange processes; reducing sodium in high-level-waste sludges; and removing sodium from acidic wastes to facilitate calcining. These applications encompass wastes stored at the Hanford, Savannah River, and Idaho National Engineering Laboratory sites. The overall project objective is to supply a salt splitting process unit that impacts the waste treatment and disposal flowsheets and meets user requirements. The potential flowsheet impacts include improving the efficiency of the waste pretreatment processes, reducing volume, and increasing the quality of the final waste disposal forms. Meeting user requirements implies developing the technology to the point where it is available as standard equipment with predictable and reliable performance. This report presents two preconceptual designs for a full-scale salt splitting process based on the RE-NaSICON membranes to distinguish critical items for testing and to provide a vision that site users can evaluate.

  20. Preconceptual design of a salt splitting process using ceramic membranes

    International Nuclear Information System (INIS)

    Inorganic ceramic membranes for salt splitting of radioactively contaminated sodium salt solutions are being developed for treating U. S. Department of Energy tank wastes. The process consists of electrochemical separation of sodium ions from the salt solution using sodium (Na) Super Ion Conductors (NaSICON) membranes. The primary NaSICON compositions being investigated are based on rare- earth ions (RE-NaSICON). Potential applications include: caustic recycling for sludge leaching, regenerating ion exchange resins, inhibiting corrosion in carbon-steel tanks, or retrieving tank wastes; reducing the volume of low-level wastes volume to be disposed of; adjusting pH and reducing competing cations to enhance cesium ion exchange processes; reducing sodium in high-level-waste sludges; and removing sodium from acidic wastes to facilitate calcining. These applications encompass wastes stored at the Hanford, Savannah River, and Idaho National Engineering Laboratory sites. The overall project objective is to supply a salt splitting process unit that impacts the waste treatment and disposal flowsheets and meets user requirements. The potential flowsheet impacts include improving the efficiency of the waste pretreatment processes, reducing volume, and increasing the quality of the final waste disposal forms. Meeting user requirements implies developing the technology to the point where it is available as standard equipment with predictable and reliable performance. This report presents two preconceptual designs for a full-scale salt splitting process based on the RE-NaSICON membranes to distinguish critical items for testing and to provide a vision that site users can evaluate

  1. Enabling graphene oxide nanosheets as water separation membranes.

    Science.gov (United States)

    Hu, Meng; Mi, Baoxia

    2013-04-16

    We report a novel procedure to synthesize a new type of water separation membrane using graphene oxide (GO) nanosheets such that water can flow through the nanochannels between GO layers while unwanted solutes are rejected by size exclusion and charge effects. The GO membrane was made via layer-by-layer deposition of GO nanosheets, which were cross-linked by 1,3,5-benzenetricarbonyl trichloride, on a polydopamine-coated polysulfone support. The cross-linking not only provided the stacked GO nanosheets with the necessary stability to overcome their inherent dispensability in water environment but also fine-tuned the charges, functionality, and spacing of the GO nanosheets. We then tested the membranes synthesized with different numbers of GO layers to demonstrate their interesting water separation performance. It was found that the GO membrane flux ranged between 80 and 276 LMH/MPa, roughly 4-10 times higher than that of most commercial nanofiltration membranes. Although the GO membrane in the present development stage had a relatively low rejection (6-46%) of monovalent and divalent salts, it exhibited a moderate rejection (46-66%) of Methylene blue and a high rejection (93-95%) of Rhodamine-WT. We conclude the paper by emphasizing that the facile synthesis of a GO membrane exploiting the ideal properties of inexpensive GO materials offers a myriad of opportunities to modify its physicochemical properties, potentially making the GO membrane a next-generation, cost-effective, and sustainable alternative to the long-existing thin-film composite polyamide membranes for water separation applications. PMID:23488812

  2. Ceramic membrane in production of recycled water; Keraamikalvo uusioveden valmistuksessa - EKT 05

    Energy Technology Data Exchange (ETDEWEB)

    Laitinen, N.; Luonsi, A.; Levaenen, E.; Maentylae, T.; Vilen, J. [Haemeen ympaeristoekeskus, Tampere (Finland)

    1998-12-31

    Applicability of ceramic ultrafiltration membrane modifications were studied with laboratory units to purify clear filtrate and biologically treated combined wastewater from high quality board manufacturing process for reuse. Also performance of polymeric membrane and ceramic membrane was compared. The performance of the membrane filtration cell, developed according to requirements of the fixed dimensions of ceramic membrane was compared with the performance of the cross-rotational commercial test unit (CR-filter) of polymeric membranes. The quality of ultrafiltration permeate, namely suspended solids, turbidity and colour, was better than the quality of lake water used in the mill. The permeate fluxes were in the range of 60-75 l/m{sup 2}h. The fouling layer primarily controlled the flux and the retention, leaving the effects of surface modifications as the secondary function. The flux was slightly higher with the biologically treated wastewater. Differences in membrane material and pore size had an effect on the cleaning ability of the membranes. The polymeric membrane and the membrane with smaller pore size were easier to clean. Tests with the CR-filter showed that the rotor increases shear forces, reduces the filtration resistance and thus increases the flux compared to the cell for ceramic membranes where the increase of shear forces can be done by increasing the flow velocities. (orig.)

  3. Cake layers and long filtration times protect ceramic micro-filtration membranes for fouling

    OpenAIRE

    Lu, J

    2013-01-01

    The objective of this research was to decrease membrane fouling of a ceramic microfiltration system and at the same time increase the recovery. A conventional operation in micro- and ultrafiltration is an in-line coagulation and a frequent hydraulic backwash. The idea about these frequent backwashes is to limit the accumulation of fouling on the membrane. But the cake layer of iron or alum flocks can also protect the membrane for pore blocking and a frequent backwash can expose the membrane f...

  4. Pre-Combustion Carbon Dioxide Capture by a New Dual Phase Ceramic-Carbonate Membrane Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Jerry

    2014-09-30

    This report documents synthesis, characterization and carbon dioxide permeation and separation properties of a new group of ceramic-carbonate dual-phase membranes and results of a laboratory study on their application for water gas shift reaction with carbon dioxide separation. A series of ceramic-carbonate dual phase membranes with various oxygen ionic or mixed ionic and electronic conducting metal oxide materials in disk, tube, symmetric, and asymmetric geometric configurations was developed. These membranes, with the thickness of 10 μm to 1.5 mm, show CO2 permeance in the range of 0.5-5×10-7 mol·m-2·s-1·Pa-1 in 500-900oC and measured CO2/N2 selectivity of up to 3000. CO2 permeation mechanism and factors that affect CO2 permeation through the dual-phase membranes have been identified. A reliable CO2 permeation model was developed. A robust method was established for the optimization of the microstructures of ceramic-carbonate membranes. The ceramic-carbonate membranes exhibit high stability for high temperature CO2 separations and water gas shift reaction. Water gas shift reaction in the dual-phase membrane reactors was studied by both modeling and experiments. It is found that high temperature syngas water gas shift reaction in tubular ceramic-carbonate dual phase membrane reactor is feasible even without catalyst. The membrane reactor exhibits good CO2 permeation flux, high thermal and chemical stability and high thermal shock resistance. Reaction and separation conditions in the membrane reactor to produce hydrogen of 93% purity and CO2 stream of >95% purity, with 90% CO2 capture have been identified. Integration of the ceramic-carbonate dual-phase membrane reactor with IGCC process for carbon dioxide capture was analyzed. A methodology was developed to identify optimum operation conditions for a membrane tube of given dimensions that would treat coal syngas with targeted performance. The calculation results show that the dual-phase membrane reactor could

  5. Ceramic membranes applied in separation of hot gases; Membranas Ceramicas para Separacion de Gases en Caliente

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The aim of this project is to develop and evaluate inorganic membranes of a ceramic type, with nanometric pore size, applied in separation of contaminants and fuel enrichment, gas mixture in coal gasification . etc. Using ceramic materials have the advantage of being highly physical and chemical resistance, which makes these membranes more adequate then metal equivalent for these applications. A support manufacture and the development of natricum membranes technology to estimate the potential fields of applications and industrial viability of ceramic membranes are the intermediate goals so that the project could be considered successful one. The project has been carried out jointly by the following entities: TGI, S. A. (Tecnologia y Gestion de la Innovacion, Spain). CIEMAT (Centro de Investigaciones energeticas, Medioambientales y Tecnologicas, Spain) and CSIC-UAM (Centro mixto Consejo Superior de Investigaciones Cientificas-Universidad Autonoma de Madrid. Instituto de Ciencias de Materiales, Spain). The range of activities proposed in this project is to get the sufficient knowledge of preparation and behaviour of separation membranes to be able to procede to the desing and manufacture of an industrial filter. The project phases include; the ameiloration of ceramic support processing methods, the fluid dynamic evaluation, technology for membrane desing and manufacturing, the mounting (setting up) of an experimental installation for testing and evaluation. As a previous step a state of the art review about the following topics was made: high temperature inorganic membranes, technology separation mechanisms, gasifications process and its previous experience applications of membranes and determination of membranes specifications and characteristics of testing conditions. At the end a new inorganic ceramic membrane, with nanometric pore size and useful in several industrial processes (filtration, separation of contaminants, fuel enrichment, purification of gas mixtures

  6. Positively charged microporous ceramic membrane for the removal of Titan Yellow through electrostatic adsorption.

    Science.gov (United States)

    Cheng, Xiuting; Li, Na; Zhu, Mengfu; Zhang, Lili; Deng, Yu; Deng, Cheng

    2016-06-01

    To develop a depth filter based on the electrostatic adsorption principle, positively charged microporous ceramic membrane was prepared from a diatomaceous earth ceramic membrane. The internal surface of the highly porous ceramic membrane was coated with uniformly distributed electropositive nano-Y2O3 coating. The dye removal performance was evaluated through pressurized filtration tests using Titan Yellow aqueous solution. It showed that positively charged microporous ceramic membrane exhibited a flow rate of 421L/(m(2)·hr) under the trans-membrane pressure of 0.03bar. Moreover it could effectively remove Titan Yellow with feed concentration of 10mg/L between pH3 to 8. The removal rate increased with the enhancement of the surface charge properties with a maximum rejection of 99.6%. This study provides a new and feasible method of removing organic dyes in wastewater. It is convinced that there will be a broad market for the application of charged ceramic membrane in the field of dye removal or recovery from industry wastewater. PMID:27266317

  7. Current status of ceramic-based membranes for oxygen separation from air.

    Science.gov (United States)

    Hashim, Salwa Meredith; Mohamed, Abdul Rahman; Bhatia, Subhash

    2010-10-15

    There has been tremendous progress in membrane technology for gas separation, in particular oxygen separation from air in the last 20 years. It provides an alternative route to the existing conventional separation processes such as cryogenic distillation and pressure swing adsorption as well as cheaper production of oxygen with high purity. This review presents the recent advances of ceramic membranes for the separation of oxygen from air at high temperature. It covers the issues and problems with respect to the selectivity and separation performance. The paper also presents different approaches applied to overcome these challenges. The future directions of ceramic-based membranes for oxygen separation from air are also presented. PMID:20813344

  8. Treatment of the Bleaching Effluent from Sulfite Pulp Production by Ceramic Membrane Filtration

    Directory of Open Access Journals (Sweden)

    Mehrdad Ebrahimi

    2015-12-01

    Full Text Available Pulp and paper waste water is one of the major sources of industrial water pollution. This study tested the suitability of ceramic tubular membrane technology as an alternative to conventional waste water treatment in the pulp and paper industry. In this context, in series batch and semi-batch membrane processes comprising microfiltration, ultrafiltration and nanofiltration, ceramic membranes were developed to reduce the chemical oxygen demand (COD and remove residual lignin from the effluent flow during sulfite pulp production. A comparison of the ceramic membranes in terms of separation efficiency and performance revealed that the two-stage process configuration with microfiltration followed by ultrafiltration was most suitable for the efficient treatment of the alkaline bleaching effluent tested herein, reducing the COD concentration and residual lignin levels by more than 35% and 70%, respectively.

  9. Effects of dissolved organic matters (DOMs) on membrane fouling in anaerobic ceramic membrane bioreactors (AnCMBRs) treating domestic wastewater.

    Science.gov (United States)

    Yue, Xiaodi; Koh, Yoong Keat Kelvin; Ng, How Yong

    2015-12-01

    Anaerobic membrane bioreactors (AnMBRs) have been regarded as a potential solution to achieve energy neutrality in the future wastewater treatment plants. Coupling ceramic membranes into AnMBRs offers great potential as ceramic membranes are resistant to corrosive chemicals such as cleaning reagents and harsh environmental conditions such as high temperature. In this study, ceramic membranes with pore sizes of 80, 200 and 300 nm were individually mounted in three anaerobic ceramic membrane bioreactors (AnCMBRs) treating real domestic wastewater to examine the treatment efficiencies and to elucidate the effects of dissolved organic matters (DOMs) on fouling behaviours. The average overall chemical oxygen demands (COD) removal efficiencies could reach around 86-88%. Although CH4 productions were around 0.3 L/g CODutilised, about 67% of CH4 generated was dissolved in the liquid phase and lost in the permeate. When filtering mixed liquor of similar properties, smaller pore-sized membranes fouled slower in long-term operations due to lower occurrence of pore blockages. However, total organic removal efficiencies could not explain the fouling behaviours. Liquid chromatography-organic carbon detection, fluorescence spectrophotometer and high performance liquid chromatography coupled with fluorescence and ultra-violet detectors were used to analyse the DOMs in detail. The major foulants were identified to be biopolymers that were produced in microbial activities. One of the main components of biopolymers--proteins--led to different fouling behaviours. It is postulated that the proteins could pass through porous cake layers to create pore blockages in membranes. Hence, concentrations of the DOMs in the soluble fraction of mixed liquor (SML) could not predict membrane fouling because different components in the DOMs might have different interactions with membranes. PMID:26255104

  10. Stress analysis and fail-safe design of bilayered tubular supported ceramic membranes

    DEFF Research Database (Denmark)

    Kwok, Kawai; Frandsen, Henrik Lund; Søgaard, Martin; Hendriksen, Peter Vang

    2014-01-01

    Supported ceramic membranes based on mixed ionic and electronic conductors are a promising technology for oxygen separation applications. In addition to chemically induced stress under oxygen activity gradients in the materials, strain mismatch between membrane and support gives rise to considera......Supported ceramic membranes based on mixed ionic and electronic conductors are a promising technology for oxygen separation applications. In addition to chemically induced stress under oxygen activity gradients in the materials, strain mismatch between membrane and support gives rise to....... Stress distributions in two membrane systems have been analyzed and routes to minimize stress are proposed. For a Ba0.5Sr0.5Co0.8Fe0.2O3−δBa0.5Sr0.5Co0.8Fe0.2O3−δ membrane supported on a porous substrate of the same material under pressure-vacuum operation, the optimal configuration in terms of...

  11. Rejection and Critical Flux of Calcium Sulphate in a Ceramic Titanium Dioxide Nanofiltration Membrane

    OpenAIRE

    Ahmed, Amer Naji

    2013-01-01

    ABSTRACTThis thesis describes the rejection efficiency and the fouling behaviour of calcium sulphate solutes in a 1 nm tubular ceramic titanium dioxide nanofiltration membrane.Calcium sulphate is considered as one of the greatest scaling potential inorganic salts that responsible for membrane fouling which represents a main challenge in the expansion of membrane processes for desalination of brackish and saline water. The surface charge type and magnitude for the composite amphoteric TiO_2 me...

  12. Gradient composite metal-ceramic foam as supportive component for planar SOFCs and MIEC membranes

    International Nuclear Information System (INIS)

    A novel approach to the design of planar gradient porous supports for the thin-film SOFCs and MIEC membranes is described. The support's thermal expansion is controlled by the creation of a two-component composite metal-ceramic foam structure. Thin MIEC membranes and SOFCs were prepared on the composite supports by the layerwise deposition of composite functional layers including complex fluorites and perovskites. Lab-scale studies demonstrated promising performance of both MIEC membrane and SOFC.

  13. Novel Ceramic-Polymer Composite Membranes for the Separation of Hazardous Liquid Waste; FINAL

    International Nuclear Information System (INIS)

    The present project was conceived to address the need for robust yet selective membranes suitable for operating in harsh ph, solvent, and temperature environments. An important goal of the project was to develop a membrane chemical modification technology that would allow one to tailor-design membranes for targeted separation tasks. The method developed in the present study is based on the process of surface graft polymerization. Using essentially the same base technology of surface modification the research was aimed at demonstrating that improved membranes can be designed for both pervaporation separation and ultrafiltration. In the case of pervaporation, the present study was the first to demonstrate that pervaporation can be achieved with ceramic support membranes modified with an essentially molecular layer of terminally anchored polymer chains. The main advantage of the above approach, relative to other proposed membranes, is that the separating polymer layer is covalently attached to the ceramic support. Therefore, such membranes have a potential use in organic-organic separations where the polymer can swell significantly yet membrane robustness is maintained due to the chemical linkage of the chains to be inorganic support. The above membrane technology was also useful in developing fouling resistant ultrafiltration membranes. The prototype membrane developed in the project was evaluated for the treatment of oil-in-water microemulsions, demonstrating lack of irreversible fouling common with commercial membranes

  14. Novel Ceramic-Polymer Composite Membranes for the Separation of Hazardous Liquid Waste

    Energy Technology Data Exchange (ETDEWEB)

    Yoram Cohen

    2001-12-01

    The present project was conceived to address the need for robust yet selective membranes suitable for operating in harsh ph, solvent, and temperature environments. An important goal of the project was to develop a membrane chemical modification technology that would allow one to tailor-design membranes for targeted separation tasks. The method developed in the present study is based on the process of surface graft polymerization. Using essentially the same base technology of surface modification the research was aimed at demonstrating that improved membranes can be designed for both pervaporation separation and ultrafiltration. In the case of pervaporation, the present study was the first to demonstrate that pervaporation can be achieved with ceramic support membranes modified with an essentially molecular layer of terminally anchored polymer chains. The main advantage of the above approach, relative to other proposed membranes, is that the separating polymer layer is covalently attached to the ceramic support. Therefore, such membranes have a potential use in organic-organic separations where the polymer can swell significantly yet membrane robustness is maintained due to the chemical linkage of the chains to be inorganic support. The above membrane technology was also useful in developing fouling resistant ultrafiltration membranes. The prototype membrane developed in the project was evaluated for the treatment of oil-in-water microemulsions, demonstrating lack of irreversible fouling common with commercial membranes.

  15. Ceramic membrane fouling during ultrafiltration of oil/water emulsions: Roles played by stabilization surfactants of oil droplets

    KAUST Repository

    Lu, Dongwei

    2015-04-07

    Oil/water (O/W) emulsion stabilized by surfactants is the part of oily wastewater that is most difficult to handle. Ceramic membrane ultrafiltration presently is an ideal process to treat O/W emulsions. However, little is known about the fouling mechanism of the ceramic membrane during O/W emulsion treatment. This paper investigated how stabilization surfactants of O/W emulsions influence the irreversible fouling of ceramic membranes during ultrafiltration. An unexpected phenomenon observed was that irreversible fouling was much less when the charge of the stabilization surfactant of O/W emulsions is opposite to the membrane. The less ceramic membrane fouling in this case was proposed to be due to a synergetic steric effect and demulsification effect which prevented the penetration of oil droplets into membrane pores and led to less pore blockage. This proposed mechanism was supported by cross section images of fouled and virgin ceramic membranes taken with scanning electron microscopy, regression results of classical fouling models, and analysis of organic components rejected by the membrane. Furthermore, this mechanism was also verified by the existence of a steric effect and demulsification effect. Our finding suggests that ceramic membrane oppositely charged to the stabilization surfactant should be applied in ultrafiltration of O/W emulsions to alleviate irreversible membrane fouling. It could be a useful rule for ceramic membrane ultrafiltration of oily wastewater. © 2015 American Chemical Society.

  16. Membrane curvature enables N-Ras lipid anchor sorting to liquid-ordered membrane phases

    DEFF Research Database (Denmark)

    Larsen, Jannik Bruun; Jensen, Martin Borch; Bhatia, Vikram Kjøller;

    2015-01-01

    Trafficking and sorting of membrane-anchored Ras GTPases are regulated by partitioning between distinct membrane domains. Here, in vitro experiments and microscopic molecular theory reveal membrane curvature as a new modulator of N-Ras lipid anchor and palmitoyl chain partitioning. Membrane...... curvature was essential for enrichment in raft-like liquid-ordered phases; enrichment was driven by relief of lateral pressure upon anchor insertion and most likely affects the localization of lipidated proteins in general....

  17. Facilitated transport ceramic membranes for high-temperature gas cleanup. Final report, February 1990--April 1994

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, R.; Minford, E.; Damle, A.S.; Gangwal, S.K.; Hart, B.A.

    1994-04-01

    The objective of this program was to demonstrate the feasibility of developing high temperature, high pressure, facilitated transport ceramic membranes to control gaseous contaminants in Integrated Gasification Combined Cycle (IGCC) power generation systems. Meeting this objective requires that the contaminant gas H{sub 2}S be removed from an IGCC gas mixture without a substantial loss of the other gaseous components, specifically H{sub 2} and CH{sub 4}. As described above this requires consideration of other, nonconventional types of membranes. The solution evaluated in this program involved the use of facilitated transport membranes consisting of molten mixtures of alkali and alkaline earth carbonate salts immobilized in a microporous ceramic support. To accomplish this objective, Air Products and Chemicals, Inc., Golden Technologies Company Inc., and Research Triangle Institute worked together to develop and test high temperature facilitated membranes for the removal of H{sub 2}S from IGCC gas mixtures. Three basic experimental activities were pursued: (1) evaluation of the H{sub 2}S chemistry of a variety of alkali and alkaline earth carbonate salt mixtures; (2) development of microporous ceramic materials which were chemically and physically compatible with molten carbonate salt mixtures under IGCC conditions and which could function as a host to support a molten carbonate mixture and; (3) fabrication of molten carbonate/ceramic immobilized liquid membranes and evaluation of these membranes under conditions approximating those found in the intended application. Results of these activities are presented.

  18. NOVEL CERAMIC MEMBRANE FOR HIGH TEMPERATURE CARBON DIOXIDE SEPARATION

    International Nuclear Information System (INIS)

    A new CO2 semi-permeable dense inorganic membrane consisting of a porous metal phase and molten carbonate was proposed. A simple direct infiltration method was used to synthesize the metal-carbonate dual-phase membrane. Hermetic (gas-tight) dual phase membrane was successfully obtained. Permeation data showed that nitrogen or helium is not permeable through the membrane (only CO2, with O2 can permeate through the membrane based on transport mechanism)

  19. Direct synthesis of a titania membrane on a centrifugally casted tubular ceramic support

    OpenAIRE

    Patterson, V.A.; Krieg, H.M.; Kriek, R.J.; Bisset, H.

    2006-01-01

    In-house manufactured tubular ceramic supports prepared by centrifugal casting have a smooth inside surface and are ideal for thin defect-free coatings. The aim of this study was to directly coat a thin defect-free titania membrane in the anatase crystal structure on a ceramic support. The membrane preparation was successful. By means of XRD it was confirmed that the continuous and defect-free titania top-layer (thickness = 1.5–1.6 μm) was in the anatase crystal structure. According to the ga...

  20. Cross-flow filtration with different ceramic membranes for polishing wastewater treatment plant effluent

    DEFF Research Database (Denmark)

    Farsi, Ali; Hammer Jensen, Sofie; Roslev, Peter;

    Nowadays the need for sustainable water treatment is essential because water shortages are increasing. Depending on the wastewater treatment plant (WWTP) effluent constituents, the effluent cannot be simply discharged to environment because it contains toxic ions and organic micropollutants which...... are harmful for aquatic organism. A possible strategy to avoid this is to polish the effluent by membrane processes. Different ceramic membranes were studied to test their ability to remove inorganic and organic compounds from the effluent. Hence, various active layers such as mesoporous TiO2 (average nominal...... linearly by membrane permeability because of pore size (Fig. 2). The ions rejection decreased nonlinearly with membrane permeability and it was not high for MF, UF and even NF membranes (Fig. 2). Hybrid silica membrane removed almost 95% of NH4+ and 85% of NO2- whereas the others membranes were less...

  1. Cross-flow filtration with different ceramic membranes for polishing wastewater treatment plant effluent

    OpenAIRE

    Farsi, Ali; Hammer Jensen, Sofie; Roslev, Peter; Boffa, Vittorio; Christensen, Morten Lykkegaard

    2014-01-01

    Nowadays the need for sustainable water treatment is essential because water shortages are increasing. Depending on the wastewater treatment plant (WWTP) effluent constituents, the effluent cannot be simply discharged to environment because it contains toxic ions and organic micropollutants which are harmful for aquatic organism. A possible strategy to avoid this is to polish the effluent by membrane processes. Different ceramic membranes were studied to test their ability to remove inorganic...

  2. Heterogeneous ceramic interfaces in solid oxide fuel cells and dense oxygen permeable membranes

    OpenAIRE

    Faaland, Sonia

    2000-01-01

    Solid oxide fuel cells and oxygen permeable membranes have received considerable attention during the last decade due to the increasing demand for electrical energy and easily transportable fuels combined with the requirement of low emission of CO2. This work concentrates on the stability of ceramic interfaces in general, and more specifically to heterophase solid state interfaces related to solid oxide fuel cells and oxygen permeable membranes. Reaction mechanisms are discussed and requireme...

  3. Evaluation of the oleophilicity of different alkoxysilane modified ceramic membranes through wetting dynamic measurements

    International Nuclear Information System (INIS)

    Wettability has been recognized as one of the most important properties of porous materials for both fundamental and practical applications. In this study, the oleophilicity of Al2O3 membranes modified by four alkoxysilanes with different length of alkyl group was investigated through oil wetting dynamic test. Fourier transform infrared spectroscopy (FTIR), thermogravimertric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) were measured to confirm that ceramic membrane surfaces have been grafted with alkoxysilanes without changing the membrane morphology. A high speed video camera was used to record the spreading and imbibition process of oil on the modified membrane surface. The value of oil contact angle and its change during the wetting process were used to characterize the membrane oleophilicity. Characterization results showed that the oleophilicity of the modified membranes increased along with the increasing of the silane alkyl group. The influence of oleophilicity on the filtration performance of water-in-oil (W/O) emulsions was experimentally studied. A higher oil flux was obtained for membranes grafted with a longer alkyl group, indicating that increase oleophilicity can increase the membrane antifouling property. This work presents a valuable route to the surface oleophilicity control and testing of ceramic membranes in the filtration of non-polar organic solvents.

  4. A POLYMER-CERAMIC COMPOSITE MEMBRANE FOR RECOVERING VOLATILE ORGANIC COMPOUNDS FROM WASTEWATERS BY PERVAPORATION

    Science.gov (United States)

    A composite membrane was constructed on a porous ceramic support from a block copolymer of styrene and butadiene (SBS). It was tested in a laboratory pervaporation apparatus for recovering volatile organic compounds (VOCs) such a 1,1,1-trichloroethane (TCA) and trichloroethylene ...

  5. Cake layers and long filtration times protect ceramic micro-filtration membranes for fouling

    NARCIS (Netherlands)

    Lu, J.

    2013-01-01

    The objective of this research was to decrease membrane fouling of a ceramic microfiltration system and at the same time increase the recovery. A conventional operation in micro- and ultrafiltration is an in-line coagulation and a frequent hydraulic backwash. The idea about these frequent backwashes

  6. High flux ceramic membrane for hydrogen separation. Final technical progress report

    Energy Technology Data Exchange (ETDEWEB)

    K. Durai-Swamy

    1999-05-04

    Fuel cells that convert hydrogen to electricity will play an increasingly important role in the generation of future electric power for stationary and transportation sector applications. However, more economic methods to produce hydrogen from fossil fuels are needed. This project addresses the need to develop low cost ceramic membranes for hydrogen separation from reformed fuels.

  7. Application of ceramic membranes for seawater reverse osmosis (SWRO) pre-treatment

    KAUST Repository

    Hamad, Juma

    2013-05-30

    Low-pressure (microfiltration/ultrafiltration (MF/UF)) membranes are being increasingly used as pre-treatment, prior to seawater reverse osmosis (SWRO). The objective of pre-treatment before reverse osmosis (RO) membranes is to remove undesirable and particulate fouling materials (algae, suspended and colloidal particles). Also, a pre-treatment barrier reduces organics and provides better feed water quality for RO membranes. MF and UF pre-treatment prior to SWRO provides Low Silt Density Index (SDI) values recommended for RO operation. Ceramic membranes are more attractive as they made of more chemically resistant materials, which allow for more stable operation and aggressive backwashing (BW) and cleaning. A pilot plant with a monolith ceramic MF membrane (0.1 μm pore size) from METAWATER was used to carry out the study. Red Sea water pumped from a distance of 700 m offshore from Thuwal (Kingdom of Saudi Arabia) was used as feed water. The pilot plant was operated automatically at constant flux of 150 LMH that involved BW, air flushing and forward flushing at the end of filtration cycle. Seawater permeates were used for hydraulic BW, while sodium hypochlorite, citric acid and sodium hydroxide were used for chemical cleaning (CIP) to restore the membrane permeability after use. Filtration cycles of 2.5 h were adopted for initial experiments. Aggressive BW flux of 1,800 LMH for 15 s, air flushing of 4 bars for 10 s and forward flushing of 300 LMH for 40 s were applied for regular membrane hydraulic cleaning. The increase of membrane resistances over time was monitored. Further studies were also performed by using Anopore ceramic membranes AAO100 (pore sizes of 0.1 μm) using a constant pressure bench-scale set-up. The feed water and permeate were analysed using an SDI unit, flow cytometre (FCM) and liquid chromatography with organic carbon detection (LC-OCD). The results showed that ceramic membrane filtration reduced the SDI15 of seawater from 6.1 to 2.1 which

  8. Electrolytic process to produce sodium hypochlorite using sodium ion conductive ceramic membranes

    Science.gov (United States)

    Balagopal, Shekar; Malhotra, Vinod; Pendleton, Justin; Reid, Kathy Jo

    2012-09-18

    An electrochemical process for the production of sodium hypochlorite is disclosed. The process may potentially be used to produce sodium hypochlorite from seawater or low purity un-softened or NaCl-based salt solutions. The process utilizes a sodium ion conductive ceramic membrane, such as membranes based on NASICON-type materials, in an electrolytic cell. In the process, water is reduced at a cathode to form hydroxyl ions and hydrogen gas. Chloride ions from a sodium chloride solution are oxidized in the anolyte compartment to produce chlorine gas which reacts with water to produce hypochlorous and hydrochloric acid. Sodium ions are transported from the anolyte compartment to the catholyte compartment across the sodium ion conductive ceramic membrane. Sodium hydroxide is transported from the catholyte compartment to the anolyte compartment to produce sodium hypochlorite within the anolyte compartment.

  9. Ceramic Membranes by Electrochemical Vapor Deposition of Zirconia-Yttria-Terbia Layers on Porous Substrates

    OpenAIRE

    Brinkman, Hendrik W.; Burggraaf, Anthonie J.

    1995-01-01

    By means of electrochemical vapor deposition (EVD), it is possible to grow thin, dense layers of zirconia/yttria/terbiasolid solution (ZYT) on porous ceramic substrates. These layers can be used as ceramic membranes for oxygen separation.The kinetics of the EVD process, the morphology of the grown layers and their oxygen permeation properties are investigated.At a deposition temperature of 800°C, the EVD layer growth is limited by bulk electrochemical transport. At 1000°Cthe layer growth is l...

  10. Cross-flow micro-filtration using ceramic membranes

    International Nuclear Information System (INIS)

    Pressurized Heavy Water Reactors have a system devoted to the purification and upgrading of the collected heavy water leaks. The purification train is fed with different degradation ratios (D2O/H2O), activities and impurities. The water is distilled in a packed bed column filled with a mesh type packing. With the purpose of minimizing the column stack corrosion, the water is pre-treated in a train consisting on an activated charcoal bed-strong cationic-anionic resin and a final polishing anionic bed resin. Traces of oils are retained by the charcoal bed but some of them pass through and could be responsible for the resins fouling. The process of micro filtration using ceramic materials is particularly applied to the treatment of waters with oil micro droplets. We describe the development stages of single and double layer filtration ceramic tubes, their characterization and the adaptation to test equipment. The efficiency was evaluated by means of tangential ('cross-flow') filtration of aqueous solutions containing dodecane at the micrograms per ml concentration level. This compound simulates the properties of a typical oil contaminant. A 100-fold reduction in the amount of dodecane in water was observed after the filtration treatment. (author)

  11. DETERMINATION OF THE MASS TRANSFER CHARACTERIZATION OF A CERAMIC-POLYMER COMPOSITE MEMBRANE IN THE PERVAPORATION MODE

    Science.gov (United States)

    The effect of the coating layer thickness on VOC extraction performance of a ceramic polymer composite membrane has been investigated. It was found, under experimental condiitons representing typical field operation, the overall mass transfer rates of feed components were control...

  12. Novel Ceramic Materials for Polymer Electrolyte Membrane Water Electrolysers' Anodes

    DEFF Research Database (Denmark)

    Polonsky, J.; Bouzek, K.; Prag, Carsten Brorson;

    2012-01-01

    Tantalum carbide was evaluated as a possible new support for the IrO2 for use in anodes of polymer electrolyte membrane water electrolysers. A series of supported electrocatalysts varying in mass content of iridium oxide was prepared. XRD, powder conductivity measurements and cyclic and linear...

  13. Dense ceramic membranes: A review of the state of the art

    Directory of Open Access Journals (Sweden)

    Kozhukharov, V.

    1999-02-01

    Full Text Available During the past several years the concepts of oxygen permeation through mixed valency ceramic membranes possess special interest. In this context, a classification and brief review of the major membrane ceramic materials will be presented. The focus will be on dense ceramic membranes as elements for advanced application. A discussion will be proposed for mixed conductor ceramics as perovskite ABO3 compounds. Dense membranes on perovskite base are the object of the present review and some details about processing and characterization of double (A- and B-site substituted La1-x Sr(BaxCo0.8Fe0.2O3-d perovskites will be presented.

    El concepto de permeación de oxígeno a través de membranas cerámicas de valencia mixta, ha venido adquiriendo especial relevancia a lo largo de los últimos años. En este contexto se hace se efectúa una clasificación y breve revisión de los materiales cerámicos más relevantes utilizados como membranas. En particular se orienta la descripción hacia las membranas cerámicas densas para aplicaciones avanzadas. Se propone un análisis de los conductores cerámicos mixtos, como los compuestos de tipo perovskita ABO3. Se realiza una revisión de los materiales de este tipo existentes, así como se describen algunos aspectos sobre el procesamiento y caracterización de las perovskitas tipo La1-x Sr(BaxCo0.8Fe0.2O3-d doblemente sustituidas (lugares A- y B-.

  14. Ultrafiltration ceramic membrane performance during the treatment of model solutions containing dye and salt

    OpenAIRE

    Alventosa De Lara, Elena; Barredo Damas, Sergio; Zuriaga Agusti, Elena; Alcaina Miranda, María Isabel; Iborra Clar, María Isabel

    2014-01-01

    The present study reports the results of the ultrafiltration with a ceramic membrane of model solutions containing NaCl and a reactive dye, which simulate textile wastewaters. The effect of salt concentration (1, 2.5 and 4 g/L NaCl) and transmembrane pressure (1, 2, and 3 bar) on the evolution over time of both permeate flux and solutes rejection was tested. Membrane fouling was also investigated in terms of analysis of resistances-in-series, determining the contribution of both reversible an...

  15. Hybrid Processes Combining Photocatalysis and Ceramic Membrane Filtration for Degradation of Humic Acids in Saline Water

    Directory of Open Access Journals (Sweden)

    Lili Song

    2016-03-01

    Full Text Available This study explored the combined effects of photocatalysis with ceramic membrane filtration for the removal of humic acid in the presence of salt; to simulate saline wastewater conditions. The effects of operating parameters, such as salinity and TiO2 concentration on permeate fluxes, total organic carbon (TOC, and UV absorbance removal, were investigated. The interaction between the humic acids and TiO2 photocatalyst played an important role in the observed flux change during ceramic membrane filtration. The results for this hybrid system showed that the TOC removal was more than 70% for both without NaCl and with the 500 ppm NaCl concentration, and 62% and 66% for 1000 and 2000 ppm NaCl concentrations. The reduction in UV absorbance was more complete in the absence of NaCl compared to the presence of NaCl. The operation of the integrated photoreactor-ceramic membrane filter over five repeat cycles is described. It can be concluded that the overall removal performance of the hybrid system was influenced by the presence of salts, as salt leads to agglomeration of TiO2 particles by suppressing the stabilising effects of electrostatic repulsion and thereby reduces the effective surface contact between the pollutant and the photocatalyst.

  16. Characterization of Ceramic Composite-Membranes Prepared by ORMOSIL Coating Sol

    Institute of Scientific and Technical Information of China (English)

    Goo-Dae Kim; Tae-Bong Kim

    2004-01-01

    Sol-gel methods offer many advantages over conventional slip-casting, including the ability to produce ceramic membranes. They are purer, more homogeneous, more reactive and contain a wider variety of compositions. We produced ormosil sol using sol-gel process under different molecular weight of polymer species [polyethylene glycol (PEG) ] in total system [Tetraethyl ortho silicate(TEOS)-polyethylene glycol (PEG)]. The properties of as-prepared ormosil sol such as,viscosity, gelation time were characterized. Also, the ceramic membrane was prepared by dip-coating with synthetic sol and its micro-structure was observed by scanning electron microscopy. The permeability and rejection efficiency of membrane for oil/water emulsion were evaluated as cross-flow apparatus. The ormosil sol coated Membrane is easily formed by steric effect of polymer and it improves flux efficiency because infiltration into porous support decreased. Its flux efficiency is elevated about 200(1/m2·h) compared with colloidal sol coated membrane at point of five minutes from starting test.

  17. Silicalite-1 zeolite membranes on unmodified and modified surfaces of ceramic supports: A comparative study

    Indian Academy of Sciences (India)

    M K Naskar; D Kundu; M Chatterjee

    2009-10-01

    Silicalite-1 zeolite membranes were prepared hydrothermally on the porous ceramic supports, both unmodified and modified with 3-aminopropyl triethoxysilane (APTES) as a coupling agent following ex situ (secondary) crystal growth process. The microstructure of the membranes was examined by scanning electron microscopy (SEM). The permeation study with a single gas, nitrogen (N2) was performed through the membranes. For the surface modified support, a more surface coverage of the seed crystals on the porous support was observed resulting in a relatively higher dense packing of the crystals during secondary crystal growth process compared to that obtained from the unmodified support. The membrane developed on surface modified support rendered lower permeance value i.e. 9 × 10-7 mol m-2 s-1 Pa-1 of N2 compared to that formed on the unmodified support which gave permeance value of 20 × 10-7 mol m-2 s-1 Pa-1 of N2.

  18. Development of a mixed-conductive ceramic membrane for syngas production

    International Nuclear Information System (INIS)

    Natural gas conversion into syngas (H2+CO) is very attractive for hydrogen and clean fuel production via GTL technology by providing an alternative to oil products and reducing greenhouse gas emission. Syngas production, using a mixed ionic-electronic conducting ceramic membrane, is thought to be particularly promising. The purpose of this PhD thesis was to develop this type of membrane. Mixed-conducting oxide was synthesized, characterized and then, shaped via tape casting and co-sintered in order to obtain multilayer membranes with controlled architectures and microstructures. Oxygen permeation fluxes were measured with a specific device to evaluate membrane performances. As a result, the optimisation of architecture and microstructure made it possible to increase oxygen permeation flux by a factor 30. Additional researches were focused on the oxide composition in order to achieve higher dimensional stability. (author)

  19. Fabrication and characterization of high performance ceramic membrane having nano metre pores

    International Nuclear Information System (INIS)

    In this study, carbon nano tubes (CNTs) were grown directly in the pores of micro porous pyrex membranes and consequently ceramic membranes with very fine pores and high porosity were achieved. Our experiment was done in two stages. Initially cobalt powder with different percent was homogeneously mixed with pyrex powder. In order to produce row membranes, each of these mixtures were compacted in the form of tablet by using of a uniaxial cold press and in a stainless steel mould, and then the tablets were sintered at different temperature in an electric furnace. In second stage chemical vapor deposition method was used to grow CNTs within the pores of the membranes. Argon and ammonia were used as carrier and reactive gas respectively and acetylene was used as the carbon feedstock. Morphology of the membranes before and after CVD process was studied by scanning electron microscopy. After CVD process CNTs were grown in the pores of membranes and the pores size was decreased but total porosity of the membrane was not changed considerably. In this way membranes with high porosity and fine pores were fabricated.

  20. Development of ceramic-supported polymeric membranes for filtration of oil emulsions

    Science.gov (United States)

    Castro, Robert P.

    Hybrid ceramic-polymeric membranes have been constructed by growing of covalently-bondedpolyvinylpyrrolidone(PVP) chains from the surface of porous inorganic supports via a graft polymerization process. The ability to manipulate the distribution of grafted polymer on the surface has been achieved through the control of the surface density of chain anchoring sites (vinyl silane molecules). The application of the modification procedure to both silica and alpha-alumina surfaces has been investigated. Resultant Ceramic-Supported Polymeric (CSP) membranes can now be produced with variable surface density and length of the terminally anchored polymer chains. Hydraulic permeability measurements were conducted to demonstrate the effect of this variation in grafted chain density and length on the water permeability of the CSP membranes. Similar measurements with a range of polar and non-polar organic solvents and both unmodified and modified membranes suggested that the permeability of the modified membrane is determined by the chemistry and configuration of the terminally anchored polymer chains. This has been attributed to the fact that the swelling (degree of extension) of the polymer brush layer increases as the solvent power increases, resulting in a decrease in the pore radius and the permeability. The separation performance of these CSP membranes have been evaluated for the cross-flow filtration of oil emulsions. For tubular silica-PVP membranes, a reduction in the TOC concentration of the permeate stream was observed with operation in the fully developed turbulent flow regime. It is hypothesized that this behavior is attributed to the ability of the grafted chains to inhibit penetration of cake layer into the pore structure from the normal component of the velocity vector.

  1. EFFICIENCY OF ULTRAFILTRATION CERAMIC MEMBRANES FOR TOXIC ELEMENTS REMOVAL FROM WASTEWATERS

    Directory of Open Access Journals (Sweden)

    S. Alami Younssi

    2010-07-01

    Full Text Available The preparation and characterization of porous ceramics multilayer ultrafiltration membrane is described. The first step consisted to prepare high-quality macroporous support in Moroccan clay. The choice of this material is based on its natural abundance and thermal stability.The microporous interlayer was then prepared by slip casting from zirconia commercial powders and finally the active UF toplayers was obtained by sol-gel route using ZnAl2O4 and TiO2 mixed sols. The performance of ultrafiltration membrane (TiO2 (50�20– ZnAl2O4 (50� was evaluated by pores diameter, water flux, thickness and molecular weight cut off (MWCO. The water permeability measured for this composite membrane is 9.42 L/(m2•h•bar, the thickness is less than 700 nm, the pore diameter is centered near 5 nm and the MWCO was about 4500 Da.

  2. PROCESSING AND CHARACTERIZATION OF TUBULAR CERAMIC SUPPORT FOR MICROFILTRATION MEMBRANE PREPARED FROM PYROPHYLLITE CLAY

    Directory of Open Access Journals (Sweden)

    Abedallah Talidi

    2011-09-01

    Full Text Available Tubular macroporous support for ceramic microfiltration membranes were prepared by extrusion followed by sintering of the low cost pyrophyllite clay. Clay powders mixed with some organic additives can be extruded to form a porous tubular support. The average pore size of the membrane is observed to increase from 5 µm to 10.8 µm when sintering temperature increase from 900 °C to 1200 °C. However, with the increase in temperature from 900 °C to 1200 °C, the support porosity is reduced from 47% to 30% and flexural strength is increased from 4 MPa to 17 MPa. The fabricated macro-porous supports are expected to have potential applications in the pre-treatment and also can be used like support for membranes of ultra-filtration.

  3. Novel Water Treatment Processes Based on Hybrid Membrane-Ozonation Systems: A Novel Ceramic Membrane Contactor for Bubbleless Ozonation of Emerging Micropollutants

    OpenAIRE

    Stylianou, Stylianos K.; Katarzyna Szymanska; Katsoyiannis, Ioannis A.; Anastasios I. Zouboulis

    2015-01-01

    The aim of this study is the presentation of novel water treatment systems based on ozonation combined with ceramic membranes for the treatment of refractory organic compounds found in natural water sources such as groundwater. This includes, firstly, a short review of possible membrane based hybrid processes for water treatment from various sources. Several practical and theoretical aspects for the application of hybrid membrane-ozonation systems are discussed, along with theoretical backgro...

  4. Nondestructive evaluation of ceramic and metal matrix composites for NASA's HITEMP and enabling propulsion materials programs

    Science.gov (United States)

    Generazio, Edward R.

    1992-01-01

    In a preliminary study, ultrasonic, x-ray opaque, and fluorescent dye penetrants techniques were used to evaluate and characterize ceramic and metal matrix composites. Techniques are highlighted for identifying porosity, fiber alignment, fiber uniformity, matrix cracks, fiber fractures, unbonds or disbonds between laminae, and fiber-to-matrix bond variations. The nondestructive evaluations (NDE) were performed during processing and after thermomechanical testing. Specific examples are given for Si3N4/SiC (SCS-6 fiber), FeCrAlY/Al2O3 fibers, Ti-15-3/SiC (SCS-6 fiber) materials, and Si3N4/SiC (SCS-6 fiber) actively cooled panel components. Results of this study indicate that the choice of the NDE tools to be used can be optimized to yield a faithful and accurate evaluation of advanced composites.

  5. On the stability of capacitance-diaphragm gauges with ceramic membranes

    International Nuclear Information System (INIS)

    Capacitance-diaphragm gauges with ceramic membranes or diaphragms have been on the market for about 15 years. The long-term stability of these devices with full scales from 13 Pa to 133 kPa has been tested in the past decade by the calibration of gauges used by the manufacturer as reference gauges on the production line. These reference gauges were calibrated annually on a primary standard. It was found that the reproducibility of these devices depends on their full scale. For 13 Pa, the annual reproducibility near full scale varied between 0.02% and 0.04%, and for full scales of 133 Pa and higher, it varied between 0.005% and 0.03% of full scale. The reproducibility of the ceramic capacitance-diaphragm gauges for full scales of 133 Pa and 1.3 kPa was significantly lower than the uncertainty of a primary standard applying the static-expansion method.

  6. High temperature ceramic membrane reactors for coal liquid upgrading. Quarterly report No. 7, March 21, 1991--June 20, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Tsotsis, T.T.

    1992-06-19

    Ceramic membranes are a new class of materials, which have shown promise in a variety of industrial applications. Their mechanical and chemical stability coupled with a wide range of operating temperatures and pressures make them suitable for environments found in coal liquid upgrading. In this project we will evaluate the performance of Sel-Gel alumina membranes in coal liquid upgrading processes under realistic temperature and pressure conditions and investigate the feasibility of using such membranes in a membrane reactor based coal liquid upgrading process. In addition, the development of novel ceramic membranes with enhanced catalytic activity for coal-liquid upgrading applications, such as carbon-coated alumina membranes, will be also investigated.

  7. Application of proton-conducting ceramics and polymer permeable membranes for gaseous tritium recovery

    International Nuclear Information System (INIS)

    In order to carry out deuterium plasma experiments on the Large Helical Device (LHD), the National Institute for Fusion Science (NIFS) is planning to install a system for the recovery of tritium from exhaust gas and effluent liquid. As well as adopting proven conventional tritium recovery systems, NIFS is planning to apply the latest technologies such as proton-conducting ceramics and membrane-type dehumidifiers in an overall strategy to ensure minimal risk in the tritium recovery process. Application of these new technologies to the tritium recovery system for the LHD deuterium plasma experiment is evaluated quantitatively using recent experimental data. (author)

  8. Development of Nano-crystalline Doped-Ceramic Enabled Fiber Sensors for High Temperature In-Situ Monitoring of Fossil Fuel Gases

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Hai [Missouri Univ. of Science and Technology, Rolla, MO (United States); Dong, Junhang [Univ. of Cincinnati, OH (United States); Lin, Jerry [Arizona State Univ., Tempe, AZ (United States); Romero, Van [New Mexico Institute of Mining and Technology, Socorro, NM (United States)

    2012-03-01

    This is a final technical report for the first project year from July 1, 2005 to Jan 31, 2012 for DoE/NETL funded project DE-FC26-05NT42439: Development of Nanocrystalline Doped-Ceramic Enabled Fiber Sensors for High Temperature In-Situ Monitoring of Fossil Fuel Gases. This report summarizes the technical progresses and achievements towards the development of novel nanocrystalline doped ceramic material-enabled optical fiber sensors for in situ and real time monitoring the gas composition of flue or hot gas streams involved in fossil-fuel based power generation and hydrogen production.

  9. Caustic Recycle from Hanford Tank Waste Using NaSICON Ceramic Membrane Salt Splitting Process

    Energy Technology Data Exchange (ETDEWEB)

    Fountain, Matthew S.; Kurath, Dean E.; Sevigny, Gary J.; Poloski, Adam P.; Pendleton, J.; Balagopal, S.; Quist, M.; Clay, D.

    2009-02-20

    A family of inorganic ceramic materials, called sodium (Na) Super Ion Conductors (NaSICON), has been studied at Pacific Northwest National Laboratory (PNNL) to investigate their ability to separate sodium from radioactively contaminated sodium salt solutions for treating U.S. Department of Energy (DOE) tank wastes. Ceramatec Inc. developed and fabricated a membrane containing a proprietary NAS-GY material formulation that was electrochemically tested in a bench-scale apparatus with both a simulant and a radioactive tank-waste solution to determine the membrane performance when removing sodium from DOE tank wastes. Implementing this sodium separation process can result in significant cost savings by reducing the disposal volume of low-activity wastes and by producing a NaOH feedstock product for recycle into waste treatment processes such as sludge leaching, regenerating ion exchange resins, inhibiting corrosion in carbon-steel tanks, or retrieving tank wastes.

  10. High temperature ceramic membrane reactors for coal liquid upgrading. Quarter report No. 9, September 21, 1991--December 20, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Tsotsis, T.T.

    1992-07-01

    In this project we intend to study a novel process concept, i.e, the use of ceramic membranes reactors in upgrading of coal derived liquids. Membrane reactors have been used in a number of catalytic reaction processes in order to overcome the limitations on conversion imposed by thermodynamic equilibrium. They have, furthermore, the inherent capability for combining reaction and separation in a single step. Thus they offer promise for improving and optimizing yield, selectivity and performance of processes involving complex liquids, as those typically found in coal liquid upgrading. Ceramic membranes are a new class of materials, which have shown promise in a variety of industrial applications. Their mechanical and chemical stability coupled with a wide range of operating temperatures and pressures make them suitable for environments found in coal liquid upgrading. In this project we will evaluate the performance of Sol-Gel alumina membranes in coal liquid upgrading processes under realistic temperature and pressure conditions and investigate the feasibility of using such membranes in a membrane reactor based coal liquid upgrading process. In addition, the development of novel ceramic membranes with enhanced catalytic activity for coal-liquid upgrading applications, such as carbon-coated alumina membranes, will be also investigated.

  11. Ceramic membrane as a pretreatment for reverse osmosis: Interaction between marine organic matter and metal oxides

    KAUST Repository

    Dramas, Laure

    2013-02-01

    Scaling and (bio)fouling phenomena can severely alter the performance of the reverse osmosis process during desalination of seawater. Pretreatments must be applied to efficiently remove particles, colloids, and also precursors of the organic fouling and biofouling. Ceramic membranes offer a lot of advantages for micro and ultrafiltration pretreatments because their initial properties can be recovered using more severe cleaning procedure. The study focuses on the interaction between metal oxides and marine organic matter. Experiments were performed at laboratory scale. The first series of experiments focus on the filtration of different fractions of natural organic matter and model compounds solutions on flat disk ceramic membranes (47 mm of diameter) characterized with different pore size and composition. Direct filtration experiments were conducted at 0.7 bar or 2 bars and at room temperature (20 ± 0.5 °C). The efficiency of backflush and alkaline cleaning were eval, and titanium oxides. Each metal oxide corresponds to a specific pore size for the disk ceramic membranes: 80, 60, and 30 nm. Different sizes of metal oxide particles are used to measure the impact of the surface area on the adsorption of the organic matter. Seawaters from the Arabian Gulf and from the Red Sea were collected during algal blooms. Cultures of algae were also performed in the laboratory and in cooperation with woods hole oceanographic institute. Solutions of algal exudates were obtained after a couple of weeks of cultivation followed by sonication. Solutions were successively filtered through GFF (0.7 lm) and 0.45 lm membrane filters before use. The dissolved organic carbon (DOC) concentration of final solution was between 1 and 4 mg/L and showed strong hydrophilic character. These various solutions were prepared with the objective to mimic the dissolved organic matter composition of seawater subjected to algal bloom. Characterization of the solutions of filtration experiments (feed

  12. Hydraulically irreversible fouling on ceramic MF/UF membranes: comparison of fouling indices, foulant composition and irreversible pore narrowing

    KAUST Repository

    Shang, Ran

    2015-05-06

    The application of ceramic membranes in water treatment is becoming increasing attractive because of their long life time and excellent chemical, mechanical and thermal stability. However, fouling of ceramic membranes, especially hydraulically irreversible fouling, is still a critical aspect affecting the operational cost and energy consumption in water treatment plants. In this study, four ceramic membranes with pore sizes or molecular weight cut-off (MWCO) of 0.20 μm, 0.14 μm, 300 kDa and 50 kDa were compared during natural surface water filtration with respect to hydraulically irreversible fouling index (HIFI), foulant composition and narrowing of pore size due to the irreversible fouling. Our results showed that the hydraulically irreversible fouling index (HIFI) was proportional to the membrane pore size (r2=0.89) when the same feed water was filtrated. The UF membranes showed lower HIFI values than the MF membranes. Pore narrowing (internal fouling) was found to be a main fouling pattern of the hydraulically irreversible fouling. The internal fouling was caused by monolayer adsorption of foulants with different sizes that is dependent on the size of the membrane pore.

  13. A Fully Nonmetallic Gas Turbine Engine Enabled by Additive Manufacturing of Ceramic Composites. Part III; Additive Manufacturing and Characterization of Ceramic Composites

    Science.gov (United States)

    Halbig, Michael C.; Grady, Joseph E.; Singh, Mrityunjay; Ramsey, Jack; Patterson, Clark; Santelle, Tom

    2015-01-01

    This publication is the third part of a three part report of the project entitled "A Fully Nonmetallic Gas Turbine Engine Enabled by Additive Manufacturing" funded by NASA Aeronautics Research Institute (NARI). The objective of this project was to conduct additive manufacturing to produce ceramic matrix composite materials and aircraft engine components by the binder jet process. Different SiC powders with median sizes ranging from 9.3 to 53.0 microns were investigated solely and in powder blends in order to maximize powder packing. Various infiltration approaches were investigated to include polycarbosilane (SMP-10), phenolic, and liquid silicon. Single infiltrations of SMP-10 and phenolic only slightly filled in the interior. When the SMP-10 was loaded with sub-micron sized SiC powders, the infiltrant gave a much better result of filling in the interior. Silicon carbide fibers were added to the powder bed to make ceramic matrix composite materials. Microscopy showed that the fibers were well distributed with no preferred orientation on the horizontal plane and fibers in the vertical plane were at angles as much as 45deg. Secondary infiltration steps were necessary to further densify the material. Two to three extra infiltration steps of SMP-10 increased the density by 0.20 to 0.55 g/cc. However, the highest densities achieved were 2.10 to 2.15 g/cc. Mechanical tests consisting of 4 point bend tests were conducted. Samples from the two CMC panels had higher strengths and strains to failure than the samples from the two nonfiber reinforced panels. The highest strengths were from Set N with 65 vol% fiber loading which had an average strength of 66 MPa. Analysis of the fracture surfaces did not reveal pullout of the reinforcing fibers. Blunt fiber failure suggested that there was not composite behavior. The binder jet additive manufacturing method was used to also demonstrate the fabrication of turbine engine vane components of two different designs and sizes. The

  14. Absorbing TiOx thin film enabling laser welding of polyurethane membranes and polyamide fibers

    Science.gov (United States)

    Amberg, Martin; Haag, Alexander; Storchenegger, Raphael; Rupper, Patrick; Lehmeier, Frederike; Rossi, René M.; Hegemann, Dirk

    2015-10-01

    We report on the optical properties of thin titanium suboxide (TiOx) films for applications in laser transmission welding of polymers. Non-absorbing fibers were coated with TiOx coatings by reactive magnetron sputtering. Plasma process parameters influencing the chemical composition and morphology of the deposited thin films were investigated in order to optimize their absorption properties. Optical absorption spectroscopy showed that the oxygen content of the TiOx coatings is the main parameter influencing the optical absorbance. Overtreatment (high power plasma input) of the fiber surface leads to high surface roughness and loss of mechanical stability of the fiber. The study shows that thin substoichiometric TiOx films enable the welding of very thin polyurethane membranes and polyamide fibers with improved adhesion properties.

  15. Electrolytic membrane extraction enables production of fine chemicals from biorefinery sidestreams.

    Science.gov (United States)

    Andersen, Stephen J; Hennebel, Tom; Gildemyn, Sylvia; Coma, Marta; Desloover, Joachim; Berton, Jan; Tsukamoto, Junko; Stevens, Christian; Rabaey, Korneel

    2014-06-17

    Short-chain carboxylates such as acetate are easily produced through mixed culture fermentation of many biological waste streams, although routinely digested to biogas and combusted rather than harvested. We developed a pipeline to extract and upgrade short-chain carboxylates to esters via membrane electrolysis and biphasic esterification. Carboxylate-rich broths are electrolyzed in a cathodic chamber from which anions flux across an anion exchange membrane into an anodic chamber, resulting in a clean acid concentrate with neither solids nor biomass. Next, the aqueous carboxylic acid concentrate reacts with added alcohol in a water-excluding phase to generate volatile esters. In a batch extraction, 96 ± 1.6% of the total acetate was extracted in 48 h from biorefinery thin stillage (5 g L(-1) acetate) at 379 g m(-2) d(-1) (36% Coulombic efficiency). With continuously regenerated thin stillage, the anolyte was concentrated to 14 g/L acetic acid, and converted at 2.64 g (acetate) L(-1) h(-1) in the first hour to ethyl acetate by the addition of excess ethanol and heating to 70 °C, with a final total conversion of 58 ± 3%. This processing pipeline enables direct production of fine chemicals following undefined mixed culture fermentation, embedding carbon in industrial chemicals rather than returning them to the atmosphere as carbon dioxide. PMID:24844669

  16. Separation Properties of Wastewater Containing O/W Emulsion Using Ceramic Microfiltration/Ultrafiltration (MF/UF) Membranes

    OpenAIRE

    Kanji Matsumoto; Kazuho Nakamura

    2013-01-01

    Washing systems using water soluble detergent are used in electrical and mechanical industries and the wastewater containing O/W emulsion are discharged from these systems. Membrane filtration has large potential for the efficient separation of O/W emulsion for reuses of treated water and detergent. The separation properties of O/W emulsions by cross-flow microfiltration and ultrafiltration were studied with ceramic MF and UF membranes. The effects of pore size; applied pressure; cross-flow v...

  17. Impact of PAC Fines in Fouling of Polymeric and Ceramic Low-Pressure Membranes for Drinking Water Treatment

    Directory of Open Access Journals (Sweden)

    Laurent Oligny

    2016-07-01

    Full Text Available This study assessed the issue of membrane fouling in a Hybrid Membrane Process (HMP due to the export of powdered activated carbon (PAC fines from a pretreatment contactor. Two parallel pilot-scale ceramic and polymeric membranes were studied. Reversible and irreversible foulings were measured following three cleaning procedures: Physical backwashing (BW, chemically enhanced backwashing (CEB and Clean-in-Place (CIP. The impacts on fouling of membrane type, operation flux increase and the presence/absence of the PAC pretreatment were investigated. Membranes without pretreatment were operated in parallel as a control. In addition, CIP washwaters samples were analyzed to measure organic and inorganic foulants removed from the membranes. It was observed that for the polymeric membranes, fouling generally increased with the presence of the PAC pretreatment because of the export of fines. On the contrary, the ceramic membranes were not significantly impacted by their presence. The analysis of CIP washwaters showed a greater total organic carbon (TOC content on membranes with a PAC pretreatment while no similar conclusion could be made for inorganic foulants.

  18. Impact of PAC Fines in Fouling of Polymeric and Ceramic Low-Pressure Membranes for Drinking Water Treatment.

    Science.gov (United States)

    Oligny, Laurent; Bérubé, Pierre R; Barbeau, Benoit

    2016-01-01

    This study assessed the issue of membrane fouling in a Hybrid Membrane Process (HMP) due to the export of powdered activated carbon (PAC) fines from a pretreatment contactor. Two parallel pilot-scale ceramic and polymeric membranes were studied. Reversible and irreversible foulings were measured following three cleaning procedures: Physical backwashing (BW), chemically enhanced backwashing (CEB) and Clean-in-Place (CIP). The impacts on fouling of membrane type, operation flux increase and the presence/absence of the PAC pretreatment were investigated. Membranes without pretreatment were operated in parallel as a control. In addition, CIP washwaters samples were analyzed to measure organic and inorganic foulants removed from the membranes. It was observed that for the polymeric membranes, fouling generally increased with the presence of the PAC pretreatment because of the export of fines. On the contrary, the ceramic membranes were not significantly impacted by their presence. The analysis of CIP washwaters showed a greater total organic carbon (TOC) content on membranes with a PAC pretreatment while no similar conclusion could be made for inorganic foulants. PMID:27399788

  19. Novel ceramic-polymer composite membranes for the separation of hazardous liquid waste. 1998 annual progress report

    International Nuclear Information System (INIS)

    'This report summarizes the work progress over the last 1.75 years of a 3 year project. The objectives of the project have been to develop a new class of ceramic-supported polymeric membranes that could be tailored-designed for a wide-range of applications in remediation and pollution prevention. To date, a new class of chemically-modified ceramic membranes was developed for the treatment of oil-in-water emulsions and for the pervaporation removal of volatile organics from aqueous systems. These new ceramic-supported polymer (CSP) membranes are fabricated by modifying the pore surface of a ceramic membrane support by a graft polymerization process (Chaimberg and Cohen, 1994). The graft polymerization process consists of activating the membrane surface with alkoxy vinyl silanes onto which vinyl monomers are added via free-radical graft polymerization resulting in a thin surface layer of terminally anchored polymer chains. Reaction conditions are selected based on knowledge of the graft polymerization kinetics for the specific polymer/substrate system. The resultant ceramic-supported polymer (CSP) membrane is a composite structure in which mechanical strength is provided by the ceramic support and the selectivity is determined by the covalently bonded polymer brush layer. Thus, one of the unique attributes of the CSP membrane is that it can be used in environments where the polymer layer is swollen (or even completely miscible) in the mixture to be separated (Castro et al., 1993). It is important to note that the above modification process is carried out under mild conditions (e.g., temperature of about 70 C) and is well suited for large scale commercial application. In a series of studies, the applicability of a polyvinylpyrrolidone CSP membrane was demonstrated for the treatment of oil-in-water emulsion under a variety of flow conditions (Castro et al.,1996). Improved membrane performance was achieved due to minimization of surface adsorption of the oil components

  20. Functionalization of Ceramic Metal Oxide Powders and Ceramic Membranes by Perfluoroalkylsilanes and Alkylsilanes Possessing Different Reactive Groups: Physicochemical and Tribological Properties.

    Science.gov (United States)

    Kujawa, Joanna; Kujawski, Wojciech

    2016-03-23

    The functionalization of ceramic materials, metal oxide powders (TiO2 and ZrO2), and ceramic membranes (5 kD TiO2 and 300 kD TiO2) was performed and thoroughly discussed. The objective of the functionalization was to change the natively hydrophilic character to the hydrophobic. The hydrophilic character of the ceramics generates limitations in wider application of such materials. Material functionalization was performed using perfluoroalkylsilanes and trifunctional(octyl)silanes possessing three different reactive functional groups: -Cl, -OMe, and -OEt. The characterization of functionalized metal oxide powders and ceramic membranes was assessed by a combination of various analytical methods and techniques: NMR, TGA, HR-TEM, FT-IR, SEM-EDX, AFM, and contact goniometry. The impact of molecular structure of grafting agents (type of reactive group), time of functionalization process (5-15 min), and type of membrane morphology on the material, physicochemical, and tribological properties was studied. Effectiveness of hydrophobization was confirmed by HR-TEM technique. The thickness of the attached hydrophobic nanolayer on the surface of ceramics was around 2.2 nm. It was found that the stable hydrophobic surfaces were obtained by functionalization with both fluorinated and nonfluorinated modifiers. The materials modified with perfluoroalkylsilanes (FC6OEt3) and trichloro(octyl)silanes (C6Cl3) during 15 min hydrophobization possess comparable properties: contact angle (CA) equal to 130° and 133°; roughness RMS of 10.2 and 12 nm; adhesive force of 4.1 and 5.7 nN; and Young modulus of 135 and 130 GPa, respectively. The relation between hydrophobicity level and ceramic membrane roughness was discussed applying the Kao diagram concept. (29)Si NMR results show that type of modifier has an important influence on grafting efficiency and on the mode of the grafting molecules attachment. In case of grafting with n-octyltrichlorosilane (C6OCl3) and n-octyltrimethoxysilane (C6

  1. Novel Water Treatment Processes Based on Hybrid Membrane-Ozonation Systems: A Novel Ceramic Membrane Contactor for Bubbleless Ozonation of Emerging Micropollutants

    Directory of Open Access Journals (Sweden)

    Stylianos K. Stylianou

    2015-01-01

    Full Text Available The aim of this study is the presentation of novel water treatment systems based on ozonation combined with ceramic membranes for the treatment of refractory organic compounds found in natural water sources such as groundwater. This includes, firstly, a short review of possible membrane based hybrid processes for water treatment from various sources. Several practical and theoretical aspects for the application of hybrid membrane-ozonation systems are discussed, along with theoretical background regarding the transformation of target organic pollutants by ozone. Next, a novel ceramic membrane contactor, bringing into contact the gas phase (ozone and water phase without the creation of bubbles (bubbleless ozonation, is presented. Experimental data showing the membrane contactor efficiency for oxidation of atrazine, endosulfan, and methyl tert-butyl ether (MTBE are shown and discussed. Almost complete endosulfan degradation was achieved with the use of the ceramic contactor, whereas atrazine degradation higher than 50% could not be achieved even after 60 min of reaction time. Single ozonation of water containing MTBE could not result in a significant MTBE degradation. MTBE mineralization by O3/H2O2 combination increased at higher pH values and O3/H2O2 molar ratio of 0.2 reaching a maximum of around 65%.

  2. Preliminary investigation of gas transport mechanism in a H+ irradiated polyimide-ceramic composite membrane

    International Nuclear Information System (INIS)

    Recent research by our group indicated that ion beam irradiation can simultaneously increase the gas permeability and permselectivity of polymeric membrane materials. The temperature dependence of the gas permeation properties of a H+ ion irradiated polyimide-ceramic composite membrane was investigated to address issues of changes in the gas transport mechanism in irradiated polymers. As was seen for glassy polymers, the temperature dependence of the permeation properties of the irradiated membrane followed an Arrhenius type relationship. Both the activation energy (Ep) for gas permeation and the pre-exponential factor (P0) of the irradiated polymer were greater than the values of the unmodified bulk polymer. Large increases in the pre-exponential factor of the irradiated sample for small size gas molecules (He, O2 and CO2) combined with the dominant contribution of the pre-exponential factor to the permselectivity for several gas pairs (He/CH4, O2/N2, and CO2/CH4) implied that the irradiated sample had a different permeation mechanism than the bulk material

  3. A process efficiency assessment of serum protein removal from milk using ceramic graded permeability microfiltration membrane.

    Science.gov (United States)

    Tremblay-Marchand, D; Doyen, A; Britten, M; Pouliot, Y

    2016-07-01

    Microfiltration (MF) is a well-known process that can be used in the dairy industry to separate caseins from serum proteins (SP) in skim milk using membranes with a pore diameter of 0.1μm. Graded permeability ceramic membranes have been studied widely as means of improving milk fractionation by overcoming problems encountered with other MF membranes. The ideal operating parameters for process efficiency in terms of membrane selectivity, permeate flux, casein loss, SP transmission, energy consumption, and dilution with water remain to be determined for this membrane. Our objective was to evaluate the effects of transmembrane pressure (TMP), volumetric concentration factor (VCF), and diafiltration on overall process efficiency. Skim milk was processed using a pilot-scale MF system equipped with 0.72-m(2) graded permeability membranes with a pore size of 0.1μm. In the first experiment, in full recycle mode, TMP was set at 124, 152, 179, or 207 kPa by adjusting the permeate pressure at the outlet. Whereas TMP had no significant effect on permeate and retentate composition, 152 kPa was found to be optimal for SP removal during concentration and concentration or diafiltration experiments. When VCF was increased to 3×, SP rejection coefficient increased along with energy consumption and total casein loss, whereas SP removal rate decreased. Diafiltering twice allowed an increase in total SP removal but resulted in a substantial increase in energy consumption and casein loss. It also reduced the SP removal rate by diluting permeate. The membrane surface area required for producing cheese milk by blending whole milk, cream, and MF retentate (at different VCF) was estimated for different cheese milk casein concentrations. For a given casein concentration, the same quantity of permeate and SP would be produced, but less membrane surface area would be needed at a lower retentate VCF. Microfiltration has great potential as a process of adding value to conventional

  4. Synthesis of inorganic materials in a supercritical carbon dioxide medium. Application to ceramic cross-flow filtration membranes preparation

    International Nuclear Information System (INIS)

    Membrane separations, using cross-flow mineral ceramic membranes, allows fractionation of aqueous solutions due to the molecular sieve effect and electrostatic charges. To obtain a high selectivity, preparation of new selective ceramic membranes is necessary. We propose in this document two different routes to prepare such cross-flow tubular mineral membranes. In the first exposed method, a ceramic material is used, titanium dioxide, synthesized in supercritical carbon dioxide by the hydrolysis of an organometallic precursor of the oxide. The influence of operating parameters is similar to what is observed during a liquid-phase synthesis (sol-gel process), and leads us to control the size and texture of the prepared particles. This material is then used to prepare mineral membrane with a compressed layer process. The particles are mixed with organic components to form a liquid suspension. A layer is then deposited on the internal surface of a tubular porous support by slip-casting. The layer is then dried and compressed on the support before sintering. The obtained membranes arc in the ultrafiltration range. A second process has been developed in this work. It consists on the hydrolysis, in a supercritical CO2 medium, of a precursor of titanium dioxide infiltrated into the support. The obtained material is then both deposited on the support but also infiltrated into the porosity. This new method leads to obtain ultrafiltration membranes that retain molecules which molecular weight is round 4000 g.mol-1. Furthermore, we studied mass transfer mechanisms in cross-flow filtration of aqueous solutions. An electrostatic model, based on generalized Nernst-Planck equation that takes into account electrostatic interactions between solutes and the ceramic material, lead us to obtain a good correlation between experimental results and the numerical simulation. (author)

  5. High temperature seals between ceramic separation membranes and super-alloy housing

    Science.gov (United States)

    Honea, G.; Sridhar, K. R.

    1991-01-01

    One of the concepts for oxygen production from Martian atmospheric carbon dioxide involves the use of tubular electrochemical membranes for oxygen separation. The tubular configuration offers the advantage of being able to separate the oxygen at pressures of up to 500 psi, thereby eliminating the need for a pre-liquefaction oxygen compressor. A key technology that has to be developed in order for the electrochemical separator to combine as a compressor is a high temperature static seal between the ceramic separation cell and the nickel-based super-alloy tube. Equipment was designed and fabricated to test the seals. Efforts are under way to develop a finite element model to study the thermal stresses at the joints and on the seal, and the optimal shape of the seal. The choice of seal materials and the technique to be used to fabricate the seals are also being investigated.

  6. Wettability modified nanoporous ceramic membrane for simultaneous residual heat and condensate recovery

    Science.gov (United States)

    Hu, H. W.; Tang, G. H.; Niu, D.

    2016-06-01

    Recovery of both latent heat and condensate from boiler flue gas is significant for improving boiler efficiency and water conservation. The condensation experiments are carried out to investigate the simultaneous heat and mass transfer across the nanoporous ceramic membranes (NPCMs) which are treated to be hydrophilic and hydrophobic surfaces using the semicontinuous supercritical reactions. The effects of typical parameters including coolant flow rate, vapor/nitrogen gas mixture temperature, water vapor volume fraction and transmembrane pressure on heat and mass transfer performance are studied. The experimental results show that the hydrophilic NPCM exhibits higher performances of condensation heat transfer and condensate recovery. However, the hydrophobic modification results in remarkable degradation of heat and condensate recovery from the mixture. Molecular dynamics simulations are conducted to establish a hydrophilic/hydrophobic nanopore/water liquid system, and the infiltration characteristics of the single hydrophilic/hydrophobic nanopore is revealed.

  7. Hydrophilic, bactericidal nanoheater-enabled reverse osmosis membranes to improve fouling resistance.

    Science.gov (United States)

    Ray, Jessica R; Tadepalli, Sirimuvva; Nergiz, Saide Z; Liu, Keng-Ku; You, Le; Tang, Yinjie; Singamaneni, Srikanth; Jun, Young-Shin

    2015-06-01

    Polyamide (PA) semipermeable membranes typically used for reverse osmosis water treatment processes are prone to fouling, which reduces the amount and quality of water produced. By synergistically coupling the photothermal and bactericidal properties of graphene oxide (GO) nanosheets, gold nanostars (AuNS), and hydrophilic polyethylene glycol (PEG) on PA reverse osmosis membrane surfaces, we have dramatically improved fouling resistance of these membranes. Batch fouling experiments from three classes of fouling are presented: mineral scaling (CaCO3 and CaSO4), organic fouling (humic acid), and biofouling (Escherichia coli). Systematic analyses and a variety of complementary techniques were used to elucidate fouling resistance mechanisms from each layer of modification on the membrane surface. Both mineral scaling and organic fouling were significantly reduced in PA-GO-AuNS-PEG membranes compared to other membranes. The PA-GO-AuNS-PEG membrane was also effective in killing all near-surface bacteria compared to PA membranes. In the PA-GO-AuNS-PEG membrane, the GO nanosheets act as templates for in situ AuNS growth, which then facilitated localized heating upon irradiation by an 808 nm laser inactivating bacteria on the membrane surface. Furthermore, AuNS in the membrane assisted PEG in preventing mineral scaling on the membrane surface. In flow-through flux and foulant rejection tests, PA-GO-AuNS-PEG membranes performed better than PA membranes in the presence of CaSO4 and humic acid model foulants. Therefore, the newly suggested membrane surface modifications will not only reduce fouling from RO feeds, but can improve overall membrane performance. Our innovative membrane design reported in this study can significantly extend the lifetime and water treatment efficacy of reverse osmosis membranes to alleviate escalating global water shortage from rising energy demands. PMID:25941970

  8. Cross flow ultrafiltration of Cr (VI) using MCM-41, MCM-48 and Faujasite (FAU) zeolite-ceramic composite membranes.

    Science.gov (United States)

    Basumatary, Ashim Kumar; Kumar, R Vinoth; Ghoshal, Aloke Kumar; Pugazhenthi, G

    2016-06-01

    This work describes the removal of Cr (VI) from aqueous solution in cross flow mode using MCM-41, MCM-48 and FAU zeolite membranes prepared on circular shaped porous ceramic support. Ceramic support was manufactured using locally available clay materials via a facile uni-axial compaction method followed by sintering process. A hydrothermal technique was employed for the deposition of zeolites on the ceramic support. The porosity of ceramic support (47%) is reduced by the formation of MCM-41 (23%), MCM-48 (22%) and FAU (33%) zeolite layers. The pore size of the MCM-41, MCM-48 and FAU membrane is found to be 0.173, 0.142, and 0.153 μm, respectively, which is lower than that of the support (1.0 μm). Cross flow ultrafiltration experiments of Cr (VI) were conducted at five different applied pressures (69-345 kPa) and three cross flow rates (1.11 × 10(-7) - 2.22 × 10(-7) m(3)/s). The filtration studies inferred that the performance of the fabricated zeolite composite membranes is optimum at the maximum applied pressure (345 kPa) and the highest rejection is obtained with the lowest cross flow rate (1.11 × 10(-7) m(3)/s) for all three zeolite membrane. The permeate flux of MCM-41, MCM-48 and FAU zeolite composite membranes are almost remained constant in the entire duration of the separation process. The highest removal of 82% is shown by FAU membrane, while MCM-41 and MCM-48 display 75% and 77% of Cr (VI) removal, respectively for the initial feed concentration of 1000 ppm with natural pH of the solution at an applied pressure of 345 kPa. PMID:27031807

  9. Fracture modes in tubular LSFCO ceramic membranes under graded reducing conditions

    International Nuclear Information System (INIS)

    Highlights: ► Microstructural evolution in LSFCO membranes under graded environment is reported. ► The role of chemically induced stresses and oxygen deficiency is evaluated. ► The stress distribution is modeled by a point defect model. - Abstract: Chromium (III) oxide (Cr2O3)-doped LaSrFeO3 perovskite, La0.2Sr0.8Fe0.8Cr0.2O3−δ (LSFCO), is being considered as a potential material for applications in solid oxide fuel cells, gas separation membranes, and electrochemical reactors because of its high electro-catalytic activity. Similar to other perovskites, the performance and mechanical strength of LSFCO materials are significantly affected by environment and temperature. Here, we report a fracture gradient phenomenon in tubular C-ring-shaped LSFCO ceramic membranes under graded reducing conditions. The graded reducing condition was produced by flushing N2 on the outer side of the C-ring membranes at 1000 °C while keeping the inner side untreated. The rings were then diametrically compressed to fracture, and the resultant fracture morphology was analyzed with a scanning electron microscope (SEM). A fracture gradient with three distinct regions across the thickness of the membranes was identified on the split surfaces. In the outer region of the C-ring specimen exposed to N2, a mixed inter/transgranular fracture with a predominant intergranular pattern was observed. In the middle section of the fracture surface, a characteristic transgranular fracture of the perovskite grains was found. At the inner region of the ring, a mixed inter/transgranular fracture with a predominant transgranular pattern occurred. The mechanism of gradient fractures was attributed both to chemically induced stresses caused by oxygen diffusion and to the formation of a separate phase of oxygen-deficient perovskite in the parent perovskite. The stresses generated were modeled by a point defect model. This work provides significant information on microstructure evolutions of tubular

  10. High temperature ceramic membrane reactors for coal liquid upgrading. Quarterly report No. 10, December 21, 1991--March 20, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Tsotsis, T.T.

    1992-07-01

    In this project we will study a novel process concept, i.e., the use of ceramic membrane reactors in upgrading of coal model compounds and coal derived liquids. In general terms, the USC research team is responsible for constructing and operating the membrane reactor apparatus and for testing various inorganic membranes for the upgrading of coal derived asphaltenes and coal model compounds. The USC effort will involve the principal investigator of this project and two graduate research assistants. The ALCOA team is responsible for the preparation of the inorganic membranes, for construction and testing of the ceramic membrane modules, and for measurement of their transport properties. The ALCOA research effort will involve Dr. Paul K. T. Liu, who is the project manager of the ALCOA research team, an engineer and a technician. UNOCAL`s contribution will be limited to overall technical assistance in catalyst preparation and the operation of the laboratory upgrading membrane reactor and for analytical back-up and expertise in oil analysis and materials characterization. UNOCAL is a no-cost contractor but will be involved in all aspects of the project, as deemed appropriate.

  11. Ceramic Membrane combined with Powdered Activated Carbon (PAC) or Coagulation for Treatment of Impaired Quality Waters

    KAUST Repository

    Hamad, Juma Z.

    2013-08-29

    Ceramic membranes (CM) are robust membranes attributed with high production, long life span and stability against critical conditions. While capital costs are high, these are partially offset by lower operation and maintenance costs compared to polymeric membranes. Like any other low-pressure membrane (LPM), CM faces problems of fouling, low removal of organic matter and poor removal of trace organic compounds (TOrCs). Current pretreatment approaches that are mainly based on coagulation and adsorption can remove some organic matter but with a low removal of the biopolymers component which is responsible for fouling. Powdered activated carbon (PAC) accompanied with a LPM maintains good removal of TOrCs. However, enhanced removal of TOrCs to higher level is required. Submicron powdered activated carbon (SPAC), obtained after crushing commercial activated carbon into very fine particle, and novel activated carbon (KCU 6) which is characterized with larger pores and high surface area were employed. A pre-coating approach, which provides intimated contact between PAC and contaminants, was adopted for wastewater and (high DOC) surface water treatment. For seawater, in-line coagulation with iron III chloride was adopted. Both SPAC and KCU 6 showed good removal of biopolymers at a dose of 30 mg/L with > 85 % and 90 %, respectively. A dose of 40 mg/L of SPAC and 30 mg/L KCU 6 pre-coats were successful used in controlling membrane fouling. SPAC is suggested to remove biopolymers by physical means and adsorption while KCU 6 removed biopolymers through adsorption. Both KCU 6 and SPAC attained high removal of TOrCs whereas KCU 6 showed outstanding performance. Out of 29 TOrCs investigated, KCU 6 showed > 87 % TOrCs rejection for 28 compounds. In seawater pretreatment, transparent exopolymer particles (TEP) were found to be an important foulant. TEP promoted both reversible and irreversible fouling. TEP are highly electronegative while alumina CM is positively charged which

  12. Application of Pre-coated Microfiltration Ceramic Membrane with Powdered Activated Carbon for Natural Organic Matter Removal from Secondary Wastewater Effluent

    KAUST Repository

    Kurniasari, Novita

    2012-12-01

    Ceramic membranes offer more advantageous performances than conventional polymeric membranes. However, membrane fouling caused by Natural Organic Matters (NOM) contained in the feed water is still become a major problem for operational efficiency. A new method of ceramic membrane pre-coating with Powdered Activated Carbon (PAC), which allows extremely contact time for adsorbing aquatic contaminants, has been studied as a pre-treatment prior to ceramic microfiltration membrane. This bench scale study evaluated five different types of PAC (SA Super, G 60, KCU 6, KCU 8 and KCU 12,). The results showed that KCU 6 with larger pore size was performed better compared to other PAC when pre-coated on membrane surface. PAC pre-coating on the ceramic membrane with KCU 6 was significantly enhance NOM removal, reduced membrane fouling and improved membrane performance. Increase of total membrane resistance was suppressed to 96%. The removal of NOM components up to 92%, 58% and 56% for biopolymers, humic substances and building blocks, respectively was achieved at pre-coating dose of 30 mg/l. Adsorption was found to be the major removal mechanism of NOM. Results obtained showed that biopolymers removal are potentially correlated with enhanced membrane performance.

  13. Development of a mixed-conductive ceramic membrane for syngas production; Developpement d'une membrane ceramique conductrice mixte pour la production de gaz de synthese

    Energy Technology Data Exchange (ETDEWEB)

    Etchegoyen, G

    2005-10-15

    Natural gas conversion into syngas (H{sub 2}+CO) is very attractive for hydrogen and clean fuel production via GTL technology by providing an alternative to oil products and reducing greenhouse gas emission. Syngas production, using a mixed ionic-electronic conducting ceramic membrane, is thought to be particularly promising. The purpose of this PhD thesis was to develop this type of membrane. Mixed-conducting oxide was synthesized, characterized and then, shaped via tape casting and co-sintered in order to obtain multilayer membranes with controlled architectures and microstructures. Oxygen permeation fluxes were measured with a specific device to evaluate membrane performances. As a result, the optimisation of architecture and microstructure made it possible to increase oxygen permeation flux by a factor 30. Additional researches were focused on the oxide composition in order to achieve higher dimensional stability. (author)

  14. Mesoporous Silica MCM-48 Membrane Synthesized on a Coarse-pore α-Al2O3 Ceramic Tube

    Institute of Scientific and Technical Information of China (English)

    LIU Chun-yan; WANG Jin-qu

    2005-01-01

    A mesoporous MCM-48 membrane was synthesized on a coarse-pore a-alumina ceramic tube by hydrothermal treatment by using a cationic surfactant as the structure-directing agent under basic conditions.The products were characterized by small-angle X-ray diffraction, SEM measurements and N2 adsorption experiments. The X-ray diffraction(XRD) results show that the membrane possesses a periodic mesostructure,which is typical for an MCM-48 material. The results of the SEM measurements indicate that MCM-48 grew in the pores of the support and formed a continuous membrane. The N2 adsorption and desorption isotherms also show that the membrane is a typical mesoporous material with pore channel size of about 2.74 nm.

  15. Hot gas cleanup using ceramic cross flow membrane filters. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Ciliberti, D.F.; Smeltzer, E.E.; Alvin, M.A.; Keairns, D.L.; Bachovchin, D.M.

    1983-12-01

    The single unresolved technical issue in the commercialization of pressurized fluid-bed combustion (PPBC) for electric power production is the hot gas cleaning problem. In this technology, high-temperature and -pressure (HTHP), dust-laden flue gases from the combustor must be cleaned enough to reduce expansion turbine blade erosion to an economically acceptable level. Additionally, the level of particulate emission must be compatible with the New Source Performance Standards (NSPS) for environmental acceptability. The Department of Energy (DOE) has sponsored a wide range of research and development programs directed at the solution of this problem. These programs were divided into two classifications, one dealing with more advanced concepts where testing was to be done at relatively large scale and a second group of less advanced, novel concepts where the testing was to be carried out at a bench scale. The cross-flow ceramic membrane filter program described in this report is a member of the small-scale, novel concept group.

  16. Calcium influx rescues adenylate cyclase-hemolysin from rapid cell membrane removal and enables phagocyte permeabilization by toxin pores.

    Directory of Open Access Journals (Sweden)

    Radovan Fiser

    Full Text Available Bordetella adenylate cyclase toxin-hemolysin (CyaA penetrates the cytoplasmic membrane of phagocytes and employs two distinct conformers to exert its multiple activities. One conformer forms cation-selective pores that permeabilize phagocyte membrane for efflux of cytosolic potassium. The other conformer conducts extracellular calcium ions across cytoplasmic membrane of cells, relocates into lipid rafts, translocates the adenylate cyclase enzyme (AC domain into cells and converts cytosolic ATP to cAMP. We show that the calcium-conducting activity of CyaA controls the path and kinetics of endocytic removal of toxin pores from phagocyte membrane. The enzymatically inactive but calcium-conducting CyaA-AC⁻ toxoid was endocytosed via a clathrin-dependent pathway. In contrast, a doubly mutated (E570K+E581P toxoid, unable to conduct Ca²⁺ into cells, was rapidly internalized by membrane macropinocytosis, unless rescued by Ca²⁺ influx promoted in trans by ionomycin or intact toxoid. Moreover, a fully pore-forming CyaA-ΔAC hemolysin failed to permeabilize phagocytes, unless endocytic removal of its pores from cell membrane was decelerated through Ca²⁺ influx promoted by molecules locked in a Ca²⁺-conducting conformation by the 3D1 antibody. Inhibition of endocytosis also enabled the native B. pertussis-produced CyaA to induce lysis of J774A.1 macrophages at concentrations starting from 100 ng/ml. Hence, by mediating calcium influx into cells, the translocating conformer of CyaA controls the removal of bystander toxin pores from phagocyte membrane. This triggers a positive feedback loop of exacerbated cell permeabilization, where the efflux of cellular potassium yields further decreased toxin pore removal from cell membrane and this further enhances cell permeabilization and potassium efflux.

  17. Preparation of Al2O3-SiO2-TiO2-ZrO2 Composite Ceramic Membranes by Sol-Gel Method

    Institute of Scientific and Technical Information of China (English)

    WU Jianfeng; BAI Zhanliang; XU Xiaohong; ZHANG Ying

    2005-01-01

    Al2O3-SiO2-TiO2-ZrO2 supported membranes were prepared by Sol-Gel method. These composite ceramic membranes are level, even and no macro crack. There exist several crystalline phases such as Al2O3, TiO2(anatase), Al2SiO5, and ZrO2 in these membranes. Changing the molar ratio of Al∶Si∶Ti∶Zr,the kinds and content of crystal phases of composite membranes could be different, which may lead to a variety of microstructure of membranes. The surface nanoscale topography and microstructure of membranes were investigated by XRD,SEM,AFM,EPMA. The effects of additives and heat treatments on the surface nanoscale topography and microstructure of composite ceramic membranes were also analyzed.

  18. Development of a setup to enable stable and accurate flow conditions for membrane biofouling studies

    KAUST Repository

    Bucs, Szilárd S.

    2015-07-10

    Systematic laboratory studies on membrane biofouling require experimental conditions that are well defined and representative for practice. Hydrodynamics and flow rate variations affect biofilm formation, morphology, and detachment and impacts on membrane performance parameters such as feed channel pressure drop. There is a suite of available monitors to study biofouling, but systems to operate monitors have not been well designed to achieve an accurate, constant water flow required for a reliable determination of biomass accumulation and feed channel pressure drop increase. Studies were done with membrane fouling simulators operated in parallel with manual and automated flow control, with and without dosage of a biodegradable substrate to the feedwater to enhance biofouling rate. High flow rate variations were observed for the manual water flow system (up to ≈9%) compared to the automatic flow control system (<1%). The flow rate variation in the manual system was strongly increased by biofilm accumulation, while the automatic system maintained an accurate and constant water flow in the monitor. The flow rate influences the biofilm accumulation and the impact of accumulated biofilm on membrane performance. The effect of the same amount of accumulated biomass on the pressure drop increase was related to the linear flow velocity. Stable and accurate feedwater flow rates are essential for biofouling studies in well-defined conditions in membrane systems. © 2015 Balaban Desalination Publications. All rights reserved.

  19. Fabrication of Pd/ceramic membranes for hydrogen separation based on low-cost macroporous ceramics with pencil coating

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Xiaojuan; Chen, Weidong; Huang, Yan [State Key Laboratory of Materials-oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Xin-Mo-Fan Road 5, Nanjing 210009 (China)

    2010-08-15

    Increasing hydrogen energy utilization has greatly stimulated the development of the hydrogen-permeable palladium membrane, which is comprised of a thin layer of palladium or palladium alloy on a porous substrate. This work chose the low-cost macroporous Al{sub 2}O{sub 3} as the substrate material, and the surface modification was carried out with a conventional 2B pencil, the lead of which is composed of graphite and clay. Based on the modified substrate, a highly permeable and selective Pd/pencil/Al{sub 2}O{sub 3} composite membrane was successfully fabricated via electroless plating. The membrane was characterized by SEM (scanning electron microscopy), field-emission SEM and metallographic microscopy. The hydrogen flux and H{sub 2}/N{sub 2} selectivity of the membrane (with a palladium thickness of 5 {mu}m) under 1 bar at 723 K were 25 m{sup 3}/(m{sup 2} h) and 3700, respectively; the membrane was found to be stable during a time-on-stream of 330 h at 723 K. (author)

  20. Economic evaluation of pre-combustion CO2-capture in IGCC power plants by porous ceramic membranes

    International Nuclear Information System (INIS)

    Highlights: • Process simulations of IGCC with pre-combustion capture via membranes were done. • Most promising technology is the water–gas-shift-membrane-reactor (WGSMR). • Energetic evaluations showed minimum efficiency loss of 5.8%-points for WGSMR. • Economic evaluations identified boundary limits of membrane technology. • Cost of electricity for optimum WGSMR-case is 57 €/MW h under made assumptions. - Abstract: Pre-combustion-carbon-capture is one of the three main routes for the mitigation of CO2-emissions by fossil fueled power plants. Based on the data of a detailed technical evaluation of CO2-capture by porous ceramic membranes (CM) and ceramic membrane reactors (WGSMR) in an Integrated-Gasification-Combined-Cycle (IGCC) power plant this paper focuses on the economic effects of CO2-abatement. First the results of the process simulations are presented briefly. The analysis is based on a comparison with a reference IGCC without CO2-capture (dry syngas cooling, bituminous coal, efficiency of 47.4%). In addition, as a second reference, an IGCC process with CO2 removal based on standard Selexol-scrubbing is taken into account. The most promising technology for CO2-capture by membranes in IGCC applications is the combination of a water gas shift reactor and a H2-selective membrane into one water gas shift membrane reactor. For the WGSRM-case efficiency losses can be limited to about 6%-points (including losses for CO2 compression) for a CO2 separation degree of 90%. This is a severe reduction of the efficiency loss compared to Selexol (10.3% points) or IGCC–CM (8.6% points). The economic evaluation is based on a detailed analysis of investment and operational costs. Parameters like membrane costs and lifetime, costs of CO2-certificates and annual operating hours are taken into account. The purpose of these evaluations is to identify the minimum cost of electricity for the different capture cases for the variation of the boundary conditions

  1. Lipid-insertion enables targeting functionalization of erythrocyte membrane-cloaked nanoparticles

    Science.gov (United States)

    Fang, Ronnie H.; Hu, Che-Ming J.; Chen, Kevin N. H.; Luk, Brian T.; Carpenter, Cody W.; Gao, Weiwei; Li, Shulin; Zhang, Dong-Er; Lu, Weiyue; Zhang, Liangfang

    2013-09-01

    RBC membrane-cloaked polymeric nanoparticles represent an emerging nanocarrier platform with extended circulation in vivo. A lipid-insertion method is employed to functionalize these nanoparticles without the need for direct chemical conjugation. Insertion of both folate and the nucleolin-targeting aptamer AS1411 shows receptor-specific targeting against model cancer cell lines.RBC membrane-cloaked polymeric nanoparticles represent an emerging nanocarrier platform with extended circulation in vivo. A lipid-insertion method is employed to functionalize these nanoparticles without the need for direct chemical conjugation. Insertion of both folate and the nucleolin-targeting aptamer AS1411 shows receptor-specific targeting against model cancer cell lines. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr03064d

  2. Lipid Reconstitution-Enabled Formation of Gold Nanoparticle Clusters for Mimetic Cellular Membrane

    OpenAIRE

    Jiyoung Nam; Yong-Tae Kim; Aeyeon Kang; Kook-Han Kim; KyoRee Lee; Wan Soo Yun; Yong Ho Kim

    2016-01-01

    Gold nanoparticles (AuNPs) encapsulated within reconstituted phospholipid bilayers have been utilized in various bioapplications due to their improved cellular uptake without compromising their advantages. Studies have proved that clustering AuNPs can enhance the efficacy of theranostic effects, but controllable aggregation or oligomerization of AuNPs within lipid membranes is still challenging. Here, we successfully demonstrate the formation of gold nanoparticle clusters (AuCLs), supported b...

  3. Soil flushing, iron coprecipitation, and ceramic membrane filtration: Innovative technologies for remediating arsenic-contaminated soil and groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Redwine, J.C. [Southern Company Services, Inc., Birmingham, AL (United States)

    1995-12-31

    This paper provides a brief description and case study of soil flushing to treat contaminated groundwater. Selected reagents may be added to the flushing water to enhance contaminant removal. In the iron coprecipitation process, and iron salt is added to the contaminated water and the pH is adjusted to induce precipitation of iron oxyhydroxides. During floc formation, trace elements adsorb onto the iron floc. Cross-flow ceramic membrane filtration can be used to remove any remaining contaminant in the feed stream. In field tests, an arsenic plume flushed with citric acid was reduced by 73 percent after 6 months of treatment.

  4. Novel ceramic-polymer composite membranes for the separation of liquid waste. Annual progress report, September 15, 1996 - September 14, 1997

    International Nuclear Information System (INIS)

    'The project on ceramic-supported polymer membranes focuses on the development of a novel class of membranes for the separation of organics from both organic-aqueous and organic-organic mixtures, Theses membranes are fabricated by a graft polymerization process where polymer chains are grown onto the surface of a ceramic support membrane. The surface graft polymerization process, developed at UCLA, results in the formation of a thin polymer layer covalently bonded to the membrane pore surface as a layer of terminally anchored polymeric chains. Through the selection of the polymer most appropriate for the desired separation task, the graft polymerized surface layer can be synthesized to impart specific separation properties to the membrane. It is expected that this project will lead to the demonstration of a new technology for the tailor design of a new class of selective and robust ceramic-supported polymer membranes. This new approach will allow the rapid deployment of task-specific membranes for the separation of waste constituents for subsequent recovery, treatment or disposal. Progress to date includes the preparation of successful silica-polyvinylpyrrolidone (PVP) membrane for the treatment of oil-in-water emulsions and a silica-polyvinylacetate (PVAc) pervaporation membrane for the separation of organics from water. Current work is ongoing to study the performance of the pervaporation membrane for the removal of chlorinated organics from water and to develop a pervaporation membrane for organic-organic separation. In another aspect of the study, the authors are studying the hydrophilic PVP CSP membrane for oil-in-water emulsion treatment with the goal of determining the optimal membrane polymer surface structure as a function of various operating conditions (e.g., tube-side Reynolds number and transmembrane pressure), Work is also in progress to characterize the polymer layer by AFM and internal reflection FTIR, and to model the conformation of the polymer

  5. Incorporation of zinc for fabrication of low-cost spinel-based composite ceramic membrane support to achieve its stabilization.

    Science.gov (United States)

    Li, Lingling; Dong, Xinfa; Dong, Yingchao; Zhu, Li; You, Sheng-Jie; Wang, Ya-Fen

    2015-04-28

    In order to reduce environment risk of zinc, a spinel-based porous membrane support was prepared by the high-temperature reaction of zinc and bauxite mineral. The phase evolution process, shrinkage, porosity, mechanical property, pore size distribution, gas permeation flux and microstructure were systematically studied. The XRD results, based on a Zn/Al stoichiometric composition of 1/2, show a formation of ZnAl2O4 structure starting from 1000°C and then accomplished at 1300°C. For spinel-based composite membrane, shrinkage and porosity are mainly influenced by a combination of an expansion induced by ZnAl2O4 formation and a general densification due to amorphous liquid SiO2. The highest porosity, as high as 44%, is observed in ZnAl4 membrane support among all the investigated compositions. Compared with pure bauxite (Al), ZnAl4 composite membrane support is reinforced by ZnAl2O4 phase and inter-locked mullite crystals, which is proved by the empirical strength-porosity relationships. Also, an increase in average pore diameter and gas flux can be observed in ZnAl4. A prolonged leaching experiment reveals the zinc can be successfully incorporated into ceramic membrane support via formation of ZnAl2O4, which has substantially better resistance toward acidic attack. PMID:25655422

  6. Improved Determination of Subnuclear Position Enabled by Three-Dimensional Membrane Reconstruction.

    Science.gov (United States)

    Zhao, Yao; Schreiner, Sarah M; Koo, Peter K; Colombi, Paolo; King, Megan C; Mochrie, Simon G J

    2016-07-12

    Many aspects of chromatin biology are influenced by the nuclear compartment in which a locus resides, from transcriptional regulation to DNA repair. Further, the dynamic and variable localization of a particular locus across cell populations and over time makes analysis of a large number of cells critical. As a consequence, robust and automatable methods to measure the position of individual loci within the nuclear volume in populations of cells are necessary to support quantitative analysis of nuclear position. Here, we describe a three-dimensional membrane reconstruction approach that uses fluorescently tagged nuclear envelope or endoplasmic reticulum membrane marker proteins to precisely map the nuclear volume. This approach is robust to a variety of nuclear shapes, providing greater biological accuracy than alternative methods that enforce nuclear circularity, while also describing nuclear position in all three dimensions. By combining this method with established approaches to reconstruct the position of diffraction-limited chromatin markers-in this case, lac Operator arrays bound by lacI-GFP-the distribution of loci positions within the nuclear volume with respect to the nuclear periphery can be quantitatively obtained. This stand-alone image analysis pipeline should be of broad practical utility for individuals interested in various aspects of chromatin biology, while also providing, to our knowledge, a new conceptual framework for investigators who study organelle shape. PMID:27410730

  7. Membrane Oxidation Enables the Cytosolic Entry of Polyarginine Cell-penetrating Peptides.

    Science.gov (United States)

    Wang, Ting-Yi; Sun, Yusha; Muthukrishnan, Nandhini; Erazo-Oliveras, Alfredo; Najjar, Kristina; Pellois, Jean-Philippe

    2016-04-01

    Arginine-rich peptides can penetrate cells and consequently be used as delivery agents in various cellular applications. The activity of these reagents is often context-dependent, and the parameters that impact cell entry are not fully understood, giving rise to variability and limiting progress toward their usage. Herein, we report that the cytosolic penetration of linear polyarginine peptides is dependent on the oxidation state of the cell. In particular, we find that hypoxia and cellular antioxidants inhibit cell penetration. In contrast, oxidants promote cytosolic cell entry with an efficiency proportional to the level of reactive oxygen species generated within membranes. Moreover, an antibody that binds to oxidized lipids inhibits cell penetration, whereas extracellularly administered pure oxidized lipids enhance peptide transport into cells. Overall, these data indicate that oxidized lipids are capable of mediating the transport of polyarginine peptides across membranes. These data may also explain variability in cell-penetrating peptide performance in different experimental conditions. These new findings therefore provide new opportunities for the rational design of future cell-permeable compounds and for the optimization of delivery protocols. PMID:26888085

  8. CO2 SELECTIVE CERAMIC MEMBRANE FOR WATER-GAS-SHIFT REACTION WITH CONCOMITANT RECOVERY OF CO2

    Energy Technology Data Exchange (ETDEWEB)

    Paul K.T. Liu

    2005-07-15

    A high temperature membrane reactor (MR) has been developed to enhance the water-gas-shift (WGS) reaction efficiency with concomitant CO{sub 2} removal for sequestration. This improved WGS-MR with CO{sub 2} recovery capability is ideally suitable for integration into the Integrated Gasification Combined-Cycle (IGCC) power generation system. Two different CO{sub 2}-affinity materials were selected in this study. The Mg-Al-CO{sub 3}-layered double hydroxide (LDH) was investigated as an adsorbent or a membrane for CO{sub 2} separation. The adsorption isotherm and intraparticle diffusivity for the LDH-based adsorbent were experimentally determined, and suitable for low temperature shift (LTS) of WGS. The LDH-based membranes were synthesized using our commercial ceramic membranes as substrate. These experimental membranes were characterized comprehensively in terms of their morphology, and CO{sub 2} permeance and selectivity to demonstrate the technical feasibility. In parallel, an alternative material-base membrane, carbonaceous membrane developed by us, was characterized, which also demonstrated enhanced CO{sub 2} selectivity at the LTS-WGS condition. With optimization on membrane defect reduction, these two types of membrane could be used commercially as CO{sub 2}-affinity membranes for the proposed application. Based upon the unique CO{sub 2} affinity of the LDHs at the LTS/WGS environment, we developed an innovative membrane reactor, Hybrid Adsorption and Membrane Reactor (HAMR), to achieve {approx}100% CO conversion, produce a high purity hydrogen product and deliver a concentrated CO{sub 2} stream for disposal. A mathematical model was developed to simulate this unique one -step process. Finally a benchtop reactor was employed to generate experimental data, which were consistent with the prediction from the HAMR mathematical model. In summary, the project objective, enhancing WGS efficiency for hydrogen production with concomitant CO{sub 2} removal for

  9. Development and Characterization of Polymer-grafted Ceramic Membranes for Solvent Nanofiltration

    OpenAIRE

    Pinheiro de Melo, Ana Filipa

    2013-01-01

    The research described in this thesis focuses on the functionalization and pore size tuning of γ- and α-alumina membranes to be used for liquid separation. The research covers alumina grafted membranes with different silanes (alkyltrichlorosilanes and aminotrialkoxysilanes) and polymers like PDMS and polyimides. In addition, the application of these materials as membranes in solvent nanofiltration is described.

  10. Treatment of oil sands process-affected water (OSPW) using a membrane bioreactor with a submerged flat-sheet ceramic microfiltration membrane.

    Science.gov (United States)

    Xue, Jinkai; Zhang, Yanyan; Liu, Yang; Gamal El-Din, Mohamed

    2016-01-01

    The release of oil sands process-affected water (OSPW) into the environment is a concern because it contains persistent organic pollutants that are toxic to aquatic life. A modified Ludzack-Ettinger membrane bioreactor (MLE-MBR) with a submerged ceramic membrane was continuously operated for 425 days to evaluate its feasibility on OSPW treatment. A stabilized biomass concentration of 3730 mg mixed liquor volatile suspended solids per litre and a naphthenic acid (NA) removal of 24.7% were observed in the reactor after 361 days of operation. Ultra Performance Liquid Chromatography/High Resolution Mass Spectrometry analysis revealed that the removal of individual NA species declined with increased ring numbers. Pyrosequencing analysis revealed that Betaproteobacteria were dominant in sludge samples from the MLE-MBR, with microorganisms such as Rhodocyclales and Sphingobacteriales capable of degrading hydrocarbon and aromatic compounds. During 425 days of continuous operation, no severe membrane fouling was observed as the transmembrane pressure (TMP) of the MLE-MBR never exceeded -20 kPa given that the manufacturer's suggested critical TMP for chemical cleaning is -35 kPa. Our results indicated that the proposed MLE-MBR has a good potential for removing recalcitrant organics in OSPW. PMID:26454665

  11. Influence of surface properties of filtration-layer metal oxide on ceramic membrane fouling during ultrafiltration of oil/water emulsion

    KAUST Repository

    Lu, Dongwei

    2016-04-01

    In this work, ceramic ultrafiltration membranes deposited with different metal oxides (i.e., TiO2, Fe2O3, MnO2, CuO, and CeO2) of around 10 nm in thickness and similar roughness were tested for O/W emulsion treatment. Distinct membrane fouling tendency was observed, which closely correlated to the properties of the filtration-layer metal oxides (i.e. surface hydroxyl groups, hydrophilicity, surface charge, and adhesion energy for oil droplets). In consistent with the distinct bond strength of the surface hydroxyl groups, hydrophilicity of these common metal oxides are quite different. The differences in hydrophilicity consequently lead to different adhesion of these metal oxides towards oil droplets which consists very well with irreversible membrane fouling tendency. In addition, the surface charge of the metal oxide opposite to that of emulsion can help to alleviate irreversible membrane fouling in ultrafiltration. Highly hydrophilic Fe2O3 with lowest fouling tendency could be a potential filtration-layer material for the fabrication/modification of ceramic membranes for O/W emulsion treatment. To the best of our knowledge, this is the first study clearly showing the correlations between surface properties of filtration-layer metal oxides and ceramic membrane fouling tendency by O/W emulsion.

  12. Influence of Surface Properties of Filtration-Layer Metal Oxide on Ceramic Membrane Fouling during Ultrafiltration of Oil/Water Emulsion.

    Science.gov (United States)

    Lu, Dongwei; Zhang, Tao; Gutierrez, Leo; Ma, Jun; Croué, Jean-Philippe

    2016-05-01

    In this work, ceramic ultrafiltration membranes deposited with different metal oxides (i.e., TiO2, Fe2O3, MnO2, CuO, and CeO2) of around 10 nm in thickness and similar roughness were tested for O/W emulsion treatment. A distinct membrane fouling tendency was observed, which closely correlated to the properties of the filtration-layer metal oxides (i.e., surface hydroxyl groups, hydrophilicity, surface charge, and adhesion energy for oil droplets). Consistent with the distinct bond strength of the surface hydroxyl groups, hydrophilicity of these common metal oxides is quite different. The differences in hydrophilicity consequently lead to different adhesion of these metal oxides toward oil droplets, consistent with the irreversible membrane fouling tendency. In addition, the surface charge of the metal oxide opposite to that of emulsion can help to alleviate irreversible membrane fouling in ultrafiltration. Highly hydrophilic Fe2O3 with the lowest fouling tendency could be a potential filtration-layer material for the fabrication/modification of ceramic membranes for O/W emulsion treatment. To the best of our knowledge, this is the first study clearly showing the correlations between surface properties of filtration-layer metal oxides and ceramic membrane fouling tendency by O/W emulsion. PMID:27035544

  13. Environment-oriented low-cost porous mullite ceramic membrane supports fabricated from coal gangue and bauxite

    Energy Technology Data Exchange (ETDEWEB)

    Lü, Qikai [Institute of Urban Environment, Chinese Academy of Sciences, Xiamen (China); Ningbo Urban Environment Observation and Research Station-NUEORS, Chinese Academy of Sciences, Ningbo (China); School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou (China); Dong, Xinfa [School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou (China); Zhu, Zhiwen [Institute of Urban Environment, Chinese Academy of Sciences, Xiamen (China); Ningbo Urban Environment Observation and Research Station-NUEORS, Chinese Academy of Sciences, Ningbo (China); Dong, Yingchao, E-mail: ycdong@iue.ac.cn [Institute of Urban Environment, Chinese Academy of Sciences, Xiamen (China); Ningbo Urban Environment Observation and Research Station-NUEORS, Chinese Academy of Sciences, Ningbo (China)

    2014-05-01

    Highlights: • Coal gangue was recycled to fabricate low-cost porous mullite membrane supports. • A unique volume-expansion occurred due to a mullitization-crystal-growth process. • A porous structure consists of glassy particles and embedded mullite crystals. - Abstract: Porous mullite ceramic supports for filtration membrane were successfully fabricated via recycling of coal gangue and bauxite at sintering temperatures from 1100 to 1500 °C with corn starch as pore-forming agent. The dynamic sintering behaviors, phase evolution, shrinkage, porosity and pore size, gas permeation flux, microstructure and mechanical property were systematically studied. A unique volume-expansion stage was observed at increased temperatures from 1276 to 1481 °C caused by a mullitization-crystal-growth process. During this stage, open porosity increases and pore size distributions broaden, which result in a maximum of nitrogen gas flux at 1400 °C. The X-ray diffraction results reveal that secondary mullitization took place from 1100 °C and the major phase is mullite with a content of ∼84.7 wt.% at 1400 °C. SEM images show that the as-fabricated mullite supports have a porous microstructure composed of sintered glassy particles embedded with inter-locked mullite crystals, which grew gradually with increasing temperature from rod-like into blocky-like morphologies. To obtain mullite membrane supports with sufficient porosity and acceptable mechanical strength, the relationship between porosity and mechanical strength was investigated, which was fitted using a parabolic equation.

  14. Environment-oriented low-cost porous mullite ceramic membrane supports fabricated from coal gangue and bauxite

    International Nuclear Information System (INIS)

    Highlights: • Coal gangue was recycled to fabricate low-cost porous mullite membrane supports. • A unique volume-expansion occurred due to a mullitization-crystal-growth process. • A porous structure consists of glassy particles and embedded mullite crystals. - Abstract: Porous mullite ceramic supports for filtration membrane were successfully fabricated via recycling of coal gangue and bauxite at sintering temperatures from 1100 to 1500 °C with corn starch as pore-forming agent. The dynamic sintering behaviors, phase evolution, shrinkage, porosity and pore size, gas permeation flux, microstructure and mechanical property were systematically studied. A unique volume-expansion stage was observed at increased temperatures from 1276 to 1481 °C caused by a mullitization-crystal-growth process. During this stage, open porosity increases and pore size distributions broaden, which result in a maximum of nitrogen gas flux at 1400 °C. The X-ray diffraction results reveal that secondary mullitization took place from 1100 °C and the major phase is mullite with a content of ∼84.7 wt.% at 1400 °C. SEM images show that the as-fabricated mullite supports have a porous microstructure composed of sintered glassy particles embedded with inter-locked mullite crystals, which grew gradually with increasing temperature from rod-like into blocky-like morphologies. To obtain mullite membrane supports with sufficient porosity and acceptable mechanical strength, the relationship between porosity and mechanical strength was investigated, which was fitted using a parabolic equation

  15. Optimization of protein fractionation by skim milk microfiltration: Choice of ceramic membrane pore size and filtration temperature.

    Science.gov (United States)

    Jørgensen, Camilla Elise; Abrahamsen, Roger K; Rukke, Elling-Olav; Johansen, Anne-Grethe; Schüller, Reidar B; Skeie, Siv B

    2016-08-01

    The objective of this study was to investigate how ceramic membrane pore size and filtration temperature influence the protein fractionation of skim milk by cross flow microfiltration (MF). Microfiltration was performed at a uniform transmembrane pressure with constant permeate flux to a volume concentration factor of 2.5. Three different membrane pore sizes, 0.05, 0.10, and 0.20µm, were used at a filtration temperature of 50°C. Furthermore, at pore size 0.10µm, 2 different filtration temperatures were investigated: 50 and 60°C. The transmission of proteins increased with increasing pore size, giving the permeate from MF with the 0.20-µm membrane a significantly higher concentration of native whey proteins compared with the permeates from the 0.05- and 0.10-µm membranes (0.50, 0.24, and 0.39%, respectively). Significant amounts of caseins permeated the 0.20-µm membrane (1.4%), giving a permeate with a whitish appearance and a casein distribution (αS2-CN: αS1-CN: κ-CN: β-CN) similar to that of skim milk. The 0.05- and 0.10-µm membranes were able to retain all caseins (only negligible amounts were detected). A permeate free from casein is beneficial in the production of native whey protein concentrates and in applications where transparency is an important functional characteristic. Microfiltration of skim milk at 50°C with the 0.10-µm membrane resulted in a permeate containing significantly more native whey proteins than the permeate from MF at 60°C. The more rapid increase in transmembrane pressure and the significantly lower concentration of caseins in the retentate at 60°C indicated that a higher concentration of caseins deposited on the membrane, and consequently reduced the native whey protein transmission. Optimal protein fractionation of skim milk into a casein-rich retentate and a permeate with native whey proteins were obtained by 0.10-µm MF at 50°C. PMID:27265169

  16. CVD of solid oxides in porous substrates for ceramic membrane modification

    OpenAIRE

    Lin, Y. S.; Burggraaf, A.J.

    1992-01-01

    The deposition of yttria-doped zirconia has been experimented systematically in various types of porous ceramic substrates by a modified chemical vapor deposition (CVD) process operating in an opposing reactant geometry using water vapor and corresponding metal chloride vapors as reactants. The effects of substrate pore dimension and structure, bulk-phase reactant concentration, reactant diffusivity in substrate pores and deposition temperature are experimentally studied and explained qualita...

  17. One-step Continuous Phenol Synthesis Technology via Selective Hydroxylation of Benzene over Ultrafine TS-1 in a Submerged Ceramic Membrane Reactor☆

    Institute of Scientific and Technical Information of China (English)

    Hong Jiang; Fei She; Yan Du; Rizhi Chen; Weihong Xing

    2014-01-01

    A new route towards phenol production by one-step selective hydroxylation of benzene with hydrogen peroxide over ultrafine titanium silicalites-1 (TS-1) in a submerged ceramic membrane reactor was developed, which can maintain the in situ removal of ultrafine catalyst particles from the reaction slurry and keep the process continuous. The effects of key operating parameters on the benzene conversion and phenol selectivity, as wel as the membrane filtration resistance were examined by single factor experiments. A continuous reaction process was carried out under the obtained optimum operation conditions. Results showed that the system can be continuously and stably operated over 20 h, and the benzene conversion and phenol selectivity kept at about 4%and 91%, respectively. The ceramic membrane exhibits excel ent thermal and chemical stability in the continuous reaction process.

  18. NOVEL CERAMIC-POLYMER COMPOSITE MEMBRANES FOR THE SEPARATION OF HAZARDOUS LIQUID WASTE

    Science.gov (United States)

    There is a growing need in the fields of remediation, hazardous chemical waste treatment, water treatment and pollution prevention for new processes capable of selectively separating and concentrating a target species, often present in dilute solution. Although membrane systems h...

  19. NOVEL CERAMIC-ORGANIC VAPOR PERMEATION MEMBRANES FOR VOC REMOVAL - PHASE II

    Science.gov (United States)

    Vapor permeation with highly permeable and organic-selective membranes is becoming an increasingly popular technique for preventing VOC emissions that are generated by a variety of stationary sources, including solvent and surface coating operations, gasoline storage operat...

  20. NOVEL CERAMIC MEMBRANE BIOREACTOR FOR LOW-FLOW SYSTEMS - PHASE I

    Science.gov (United States)

    Improved low-flow (50,000 gallons per day) sanitary wastewater treatment systems are needed. CeraMem Corporation's proposed approach includes a membrane bioreactor (MBR) using fully proven biological processes for biological oxygen demand oxidation and (optionally) fo...

  1. Deposition of Pd–Ag thin film membranes on ceramic supports for hydrogen purification/separation

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, A.I. [Centre of Physics, University of Minho, Campus Azurém, 4800-058 (Portugal); Pérez, P.; Rodrigues, S.C.; Mendes, A.; Madeira, L.M. [LEPAE, Chemical Engineering Department, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias s/n, 4200-465 Porto (Portugal); Tavares, C.J., E-mail: ctavares@fisica.uminho.pt [Centre of Physics, University of Minho, Campus Azurém, 4800-058 (Portugal)

    2015-01-15

    Highlights: • Thin film Pd–Ag membranes have been produced for hydrogen selectivity. • Magnetron sputtering yields Pd–Ag compact films for atomic H diffusion. • The thin film Pd–Ag membranes yielded a selectivity of α (H{sub 2}/N{sub 2}) = 10. - Abstract: Pd–Ag based membranes supported on porous α-Al{sub 2}O{sub 3} (doped with yttria-stabilized zirconia) were studied for hydrogen selective separation. Magnetron sputtering technique was employed for the synthesis of thin film membranes. The hydrogen permeation flux is affected by the membrane columnar structure, which is formed during deposition. From scanning electron microscopy analysis, it was observed that different sputtering deposition pressures lead to distinct columnar structure growth. X-ray diffraction patterns provided evidence of a Pd–Ag solid solution with an average crystallite domain size of 21 nm, whose preferential growth can be altered by the deposition pressure. The gas-permeation results have shown that the Pd–Ag membrane supported on porous α-Al{sub 2}O{sub 3} is selective toward H{sub 2}. For optimized membrane synthesis conditions, the permeance toward N{sub 2} is 0.076 × 10{sup −6} mol m{sup −2} s{sup −1} Pa{sup −1} at room temperature, whereas for a pressure difference of 300 kPa the H{sub 2}-flux is of the order of ca. 0.21 mol m{sup −2} s{sup −1}, which corresponds to a permeance of 0.71 × 10{sup −6} mol m{sup −2} s{sup −1} Pa{sup −1}, yielding a selectivity of α (H{sub 2}/N{sub 2}) = 10. These findings suggest that the membrane has a reasonable capacity to selectively permeate this gas.

  2. Environment-oriented low-cost porous mullite ceramic membrane supports fabricated from coal gangue and bauxite.

    Science.gov (United States)

    Lü, Qikai; Dong, Xinfa; Zhu, Zhiwen; Dong, Yingchao

    2014-05-30

    Porous mullite ceramic supports for filtration membrane were successfully fabricated via recycling of coal gangue and bauxite at sintering temperatures from 1100 to 1500°C with corn starch as pore-forming agent. The dynamic sintering behaviors, phase evolution, shrinkage, porosity and pore size, gas permeation flux, microstructure and mechanical property were systematically studied. A unique volume-expansion stage was observed at increased temperatures from 1276 to 1481°C caused by a mullitization-crystal-growth process. During this stage, open porosity increases and pore size distributions broaden, which result in a maximum of nitrogen gas flux at 1400°C. The X-ray diffraction results reveal that secondary mullitization took place from 1100°C and the major phase is mullite with a content of ∼84.7wt.% at 1400°C. SEM images show that the as-fabricated mullite supports have a porous microstructure composed of sintered glassy particles embedded with inter-locked mullite crystals, which grew gradually with increasing temperature from rod-like into blocky-like morphologies. To obtain mullite membrane supports with sufficient porosity and acceptable mechanical strength, the relationship between porosity and mechanical strength was investigated, which was fitted using a parabolic equation. PMID:24727016

  3. Hydrogen Permeation Properties of Perovskite-type BaCe0.9Mn0.1O3-δDense Ceramic Membrane

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The electrical conduction properties of dense BaCe0.9Mn0.1O3-δ (BCM10) membrane were investigated in the temperature range of 600-900℃. High ionic and electronic conductivities at elevated temperatures make BCM10 a potential ceramic material for hydrogen separation. Hydrogen permeation through BCM10 membranes was studied using a hightemperature permeation cell. Little hydrogen could be detected at the sweep side. However,appreciable hydrogen can permeate through BCM10 membrane coated with porous platinum black,which shows that the process of hydrogen permeation through BCM10 membranes was controlled by the catalytic decomposition and recomposition of hydrogen on the surfaces of BCM10 membranes.

  4. Hollow fibre microporous silica membranes for gas separation and pervaporation: synthesis, performance and stability

    NARCIS (Netherlands)

    Soest-Vercammen, E.L.J. van; Peters, T.A.; Fontalvo, J.; Vorstman, M.A.G.; Benes, N.E.; Dam, R.A. van; Vroon, Z.A.E.P.; Keurentjes, J.T.F.

    2005-01-01

    Thin microporous silica membranes were prepared on the outer surface of hollow fibre ceramic substrates. In principle this enables relatively fast and inexpensive production of large membrane surface area, combined with a low support resistance and a high membrane surface area/module volume ratio (>

  5. Design and optimization of porous ceramic supports for asymmetric ceria-based oxygen transport membranes

    DEFF Research Database (Denmark)

    Kaiser, Andreas; Foghmoes, Søren Preben Vagn; Pećanac, G.;

    2016-01-01

    =7). The achieved gas permeability of 2.25×10−15 m2 for a 0.4 mm thick support will not limit the gas transport for oxygen production but in partial oxidation of methane to syngas at higher oxygen fluxes. For integration of the CGO support layer into a flat, asymmetric CGO membrane, the sintering...

  6. Electrical properties and flux performance of composite ceramic hydrogen separation membranes

    DEFF Research Database (Denmark)

    Fish, J.S.; Ricote, Sandrine; O'Hayre, R.;

    2015-01-01

    an effective medium approach incorporating a term for the heterojunctions between the two phases. Hydrogen fluxes of 0.004-0.008 μmol cm-2 s-1 are obtained for a 50 volume% STN95 membrane sample (1 mm thickness) at 600-800 °C using dry argon as a sweep gas. Upon adding palladium layers as catalysts...

  7. Measuring Fracture Times Of Ceramics

    Science.gov (United States)

    Shlichta, Paul J.; Bister, Leo; Bickler, Donald G.

    1989-01-01

    Electrical measurements complement or replace fast cinematography. Electronic system measures microsecond time intervals between impacts of projectiles on ceramic tiles and fracture tiles. Used in research on ceramics and ceramic-based composite materials such as armor. Hardness and low density of ceramics enable them to disintegrate projectiles more efficiently than metals. Projectile approaches ceramic tile specimen. Penetrating foil squares of triggering device activate display and recording instruments. As ceramic and resistive film break oscilloscope plots increase in electrical resistance of film.

  8. Comparative Study on Performance and Organic Fouling of ZrO2 Ceramic Membranes in Ultrafiltration of Synthetic Water and Wastewater Treatment Plant Effluent

    KAUST Repository

    Li, Cen

    2011-07-01

    Adsorption of organic matter on ceramic membrane can lead to hydraulic-irreversible fouling, which decreases the permeate flux and the cost-efficiency of membrane devices. In order to optimize the filtration process, detailed information is necessary about the organic fouling mechanisms on ceramic membranes. In this study, dead-end filtration experiments of both synthetic water and secondary effluent from a wastewater treatment plant (WWTP) were conducted on a ZrO2 ceramic membrane. The experiment results of synthetic water showed that humic acid (HA) was able to be adsorbed by the ZrO2 membrane and cause permeate flux decline; and that HA-tryptophan mixture, at the same DOC level, promoted the filtration flux decline; DOC removal in the case of HA-tryptophan was lower than that of HA alone. It seems that hydrophilic organic matter with low molecular weight have some specific contribution to the organic fouling of the ZrO2 membrane. The results also suggest that tryptophan molecules were preferentially adsorbed on the membrane at the beginning, exposing their hydrophobic sides which might further adsorb HA from the feed water. During the filtration of WWTP effluent, protein-like substances (mainly tryptophan-like) were also preferentially adsorbed on the membrane compared with humic-like ones in the initial few cycles of filtration. More humic-like substances were adsorbed in the following filtration cycles due to the increase of membrane hydrophobicity. A significant rise in hydraulic-irreversible flux decline was obtained by decreasing pH from near pHpzc to below pHpzc of the membrane. It suggests that a positively charged surface is preferred for HA adsorption. Ionic strength increase did not affect the filtration of HA, but it lessened the hydraulic-irreversible flux decline of HA-tryptophan filtration. The adsorption of HA-tryptophan can be attributed to outersphere interaction while HA adsorption is mainly caused by inner-sphere interaction. The results of

  9. Strength degradation and failure limits of dense and porous ceramic membrane materials

    DEFF Research Database (Denmark)

    Pećanac, G.; Foghmoes, Søren Preben Vagn; Lipińska-Chwałek, M.;

    2013-01-01

    failure potential of these membrane parts, where in a complex device also the highest residual stresses should arise due to differences in thermal expansion. In particular, sensitivity of the materials to subcritical crack growth was assessed since the long-term reliability of the component does not only...... depend on its initial strength, but also on strength degradation effects. The results were subsequently used as a basis for a strength–probability–time lifetime prediction....

  10. Serum protein removal from skim milk with a 3-stage, 3× ceramic Isoflux membrane process at 50°C.

    Science.gov (United States)

    Adams, Michael C; Barbano, David M

    2013-04-01

    Small pore microfiltration (MF) can be used to remove serum proteins (SP) from skim milk. The process's SP removal efficiency directly influences the technology's economic feasibility. Our objective was to quantify the capacity of 0.14μm ceramic Isoflux MF membranes (TAMI, Nyons, France) to remove SP from skim milk. A 3-stage, 3×, feed-and-bleed MF study with diafiltration in the latter 2 stages was conducted at 50°C using Isoflux membranes to determine cumulative SP removal percentages and SP removal rates at each processing stage. The experiment was replicated 3 times starting with 3 separate lots of raw milk. In contrast to 3× MF theoretical cumulative SP removal percentages of 68, 90, and 97% after 1, 2, and 3 stages, respectively, the 3× Isoflux MF process removed only 39.5, 58.4, and 70.2% of SP after 1, 2, and 3 stages, respectively. Previous research has been published that provides the skim milk SP removal capacities of 3-stage, 3× 0.1μm ceramic Membralox (Pall Corp., Cortland, NY) uniform transmembrane pressure (UTP), 0.1μm ceramic Membralox graded permeability (GP), and 0.3μm polymeric polyvinylidene fluoride spiral-wound (PVDF-SW) MF systems (Parker-Hannifin, Process Advanced Filtration Division, Tell City, IN) at 50°C. No difference in cumulative SP removal percentage after 3 stages was detected between the Isoflux and previously published PVDF-SW values (70.3%), but SP removal was lower than published GP (96.5%) and UTP (98.3%) values. To remove 95% of SP from 1,000kg of skim milk in 12h it would take 7, 3, 3, and 7 stages with 6.86, 1.91, 2.82, and 17.98m(2) of membrane surface area for the Isoflux, GP, UTP, and PVDF-SW systems, respectively. The MF systems requiring more stages would produce additional permeate at lower protein concentrations. The ceramic MF systems requiring more surface area would incur higher capital costs. The authors hypothesize that SP removal with the Isoflux membranes was lower than theoretical for the following

  11. DLVO Approximation Methods for Predicting the Attachment of Silver Nanoparticles to Ceramic Membranes.

    Science.gov (United States)

    Mikelonis, Anne M; Youn, Sungmin; Lawler, Desmond F

    2016-02-23

    This article examines the influence of three common stabilizing agents (citrate, poly(vinylpyrrolidone) (PVP), and branched poly(ethylenimine) (BPEI)) on the attachment affinity of silver nanoparticles to ceramic water filters. Citrate-stabilized silver nanoparticles were found to have the highest attachment affinity (under conditions in which the surface potential was of opposite sign to the filter). This work demonstrates that the interaction between the electrical double layers plays a critical role in the attachment of nanoparticles to flat surfaces and, in particular, that predictions of double-layer interactions are sensitive to boundary condition assumptions (constant charge vs constant potential). The experimental deposition results can be explained when using different boundary condition assumptions for different stabilizing molecules but not when the same assumption was assumed for all three types of particles. The integration of steric interactions can also explain the experimental deposition results. Particle size was demonstrated to have an effect on the predicted deposition for BPEI-stabilized particles but not for PVP. PMID:26797148

  12. Enhancement of proton conductivity of chitosan membrane enabled by sulfonated graphene oxide under both hydrated and anhydrous conditions

    Science.gov (United States)

    Liu, Yahua; Wang, Jingtao; Zhang, Haoqin; Ma, Chuanming; Liu, Jindun; Cao, Shaokui; Zhang, Xiang

    2014-12-01

    In this study, sulfonated graphene oxide (SGO) nanosheets with controllable sulfonic acid group loading are synthesized via the facile distillation-precipitation polymerization, and then incorporated into chitosan (CS) matrix to prepare nanohybrid membranes. The microstructure and physicochemical properties of the resulting membranes are extensively investigated. Compared with CS control and GO-filled membranes, SGO-filled membranes attain enhanced thermal and mechanical stabilities due to the strong electrostatic attractions between -SO3H of SGO and -NH2 of CS, which inhibit the mobility of CS chains. Additionally, the inhibited mobility reduces the area swellings of SGO-filled membranes, reinforcing their structural stabilities. The incorporation of SGO generates acid-base pairs along CS-SGO interface, which work as facile proton-hoping sites and thus construct continuous and wide proton transfer pathways, yielding enhanced proton conductivities under both hydrated and anhydrous conditions. Meanwhile, the conductivity can be elevated by increasing the sulfonic acid group loading and content of SGO. Particularly, incorporating 2.0% S4GO can afford the nanohybrid membrane a 122.5% increase in hydrated conductivity and a 90.7% increase in anhydrous conductivity when compared with CS control membrane. The superior conduction properties then offered a significant enhancement in H2/O2 cell performances to the nanohybrid membranes, guaranteeing them to be promising proton exchange membranes.

  13. Mesoporous fluorocarbon-modified silica aerogel membranes enabling long-term continuous CO2 capture with large absorption flux enhancements.

    Science.gov (United States)

    Lin, Yi-Feng; Chen, Chien-Hua; Tung, Kuo-Lun; Wei, Te-Yu; Lu, Shih-Yuan; Chang, Kai-Shiun

    2013-03-01

    The use of a membrane contactor combined with a hydrophobic porous membrane and an amine absorbent has attracted considerable attention for the capture of CO2 because of its extensive use, low operational costs, and low energy consumption. The hydrophobic porous membrane interface prevents the passage of the amine absorbent but allows the penetration of CO2 molecules that are captured by the amine absorbent. Herein, highly porous SiO2 aerogels modified with hydrophobic fluorocarbon functional groups (CF3 ) were successfully coated onto a macroporous Al2 O3 membrane; their performance in a membrane contactor for CO2 absorption is discussed. The SiO2 aerogel membrane modified with CF3 functional groups exhibits the highest CO2 absorption flux and can be continuously operated for CO2 absorption for extended periods of time. This study suggests that a SiO2 aerogel membrane modified with CF3 functional groups could potentially be used in a membrane contactor for CO2 absorption. Also, the resulting hydrophobic SiO2 aerogel membrane contactor is a promising technology for large-scale CO2 absorption during the post-combustion process in power plants. PMID:23417984

  14. Mathematical modelling of multicomponent transport in composite all-ceramic membranes containing a zeolitic phase

    Czech Academy of Sciences Publication Activity Database

    Fíla, V.; Hrabánek, Pavel; Kočiřík, Milan; Navara, V.; Bernauer, B.; Zikánová, Arlette; Jirka, Ivan

    Oxford : Elsevier B.V./Ltd, 2008 - (Gédéon, A.; Massiani, P.; Babonneau, F.), s. 737-740 ISBN 978-0-444-53297-8. - (Studies in surface science and catalysis. Vol. 174). [International FEZA Conference /4./. Paris (FR), 01.09.2008-04.09.2008] R&D Projects: GA AV ČR(CZ) 1QS401250509; GA AV ČR IAA400400625; GA AV ČR KAN400720701; GA AV ČR IAA400400501 Institutional research plan: CEZ:AV0Z40400503 Keywords : silicalite-1-.alpha.-Al2O3 * membrane * CH4/N2 * DGM Subject RIV: CF - Physical ; Theoretical Chemistry

  15. The Flow of Vapors through Porous Ceramic Membranes Consisting of Several Layers

    Czech Academy of Sciences Publication Activity Database

    Loimer, T.; Uchytil, Petr; Řezníčková Čermáková, Jiřina

    Volume 14, Issue 1. Weinheim : WILEY-VCH Verlag, 2014, s. 685-686. ISSN 1617-7061. [Annual Meeting of the International Association of Applied Mathematics and Mechanics /85./. Erlangen (DE), 10.03.2014-14.03.2014] R&D Projects: GA MŠk 7AMB12AT010; GA MŠk(CZ) 7AMB14AT011 Institutional support: RVO:67985858 Keywords : membrane * capillary condensation * mass flux Subject RIV: CI - Industrial Chemistry, Chemical Engineering http://onlinelibrary.wiley.com/doi/10.1002/pamm.201410326/abstract

  16. Polymer-Derived Microporous Ceramics for Membranes and Sensors for High Temperature Hydrogen Purification and Sensing

    OpenAIRE

    Prasad, Ravi Mohan

    2012-01-01

    The growing interest in the use of hydrogen as main fuel has increased the need for pure hydrogen (H2) production and purification. There are several by-products (CO, H2O, CO2) associated with the production of hydrogen which might damage the production rate. Therefore, separation of hydrogen from other gases is an important step in the hydrogen production process. If H2 can be selectively removed from the product side during hydrogen production in membrane reactors, then it would be possible...

  17. Photocrosslinking and click chemistry enable the specific detection of proteins interacting with phospholipids at the membrane interface.

    Science.gov (United States)

    Gubbens, Jacob; Ruijter, Eelco; de Fays, Laurence E V; Damen, J Mirjam A; de Kruijff, Ben; Slijper, Monique; Rijkers, Dirk T S; Liskamp, Rob M J; de Kroon, Anton I P M

    2009-01-30

    New lipid analogs mimicking the abundant membrane phospholipid phosphatidylcholine were developed to photocrosslink proteins interacting with phospholipid headgroups at the membrane interface. In addition to either a phenylazide or benzophenone photoactivatable moiety attached to the headgroup, the lipid analogs contained azides attached as baits to the acyl chains. After photocrosslinking in situ in the biomembrane, these baits were used for the attachment of a fluorescent tetramethylrhodamine-alkyne conjugate or a biotin-alkyne conjugate using click chemistry, allowing for the selective detection and purification of crosslink products, respectively. Proteins crosslinked to the lipid analogs in inner mitochondrial membranes from Saccharomyces cerevisiae were detected and subsequently identified by mass spectrometry. Established interaction partners of phosphatidylcholine were found, as well as known integral and peripheral inner membrane proteins, and proteins that were not previously considered mitochondrial inner membrane proteins. PMID:19171301

  18. Effect of Cross-flow Velocity on the Critical Flux of Ceramic Membrane Filtration as a Pre-treatment for Seawater Desalination

    Institute of Scientific and Technical Information of China (English)

    CUI Zhaoliang; PENG Wenbo; FAN Yiqun; XING Weihong; XU Nanping

    2013-01-01

    Pre-treatment,which supplies a stable,high-quality feed for reverse osmosis (RO) membranes,is a critical step for successful operation in a seawater reverse osmosis plant.In this study,ceramic membrane systems were employed as pre-treatment for seawater desalination.A laboratory experiment was performed to investigate the effect of the cross-flow velocity on the critical flux and consequently to optimize the permeate flux.Then a pilot test was performed to investigate the long-term performance.The result shows that there is no significant effect of the cross-flow velocity on the critical flux when the cross-flow velocity varies in laminar flow region only or in turbulent flow region only,but the effect is distinct when the cross-flow velocity varies in the transition region.The membrane fouling is slight at the permeate flux of 150 L·m-2·h-1 and the system is stable,producing a high-quality feed (the turbidity and silt density index are less than 0.1 NTU and 3.0,respectively) for RO to ran for 2922.4 h without chemical cleaning.Thus the ceramic membranes are suitable to filtrate seawater as the pre-treatment for RO.

  19. High Gain, Very Low Areal Density, Scalable RF Apertures Enabled by Membrane Aperture Shell Technology (MAST) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose that the Membrane Aperture Shell Technology (MAST) approach be expanded with a specific focus on space exploration orbiting comm network RF aperture...

  20. Novel meloxicam releasing electrospun polymer/ceramic reinforced biodegradable membranes for periodontal regeneration applications.

    Science.gov (United States)

    Yar, Muhammad; Farooq, Ariba; Shahzadi, Lubna; Khan, Abdul Samad; Mahmood, Nasir; Rauf, Abdul; Chaudhry, Aqif Anwar; Rehman, Ihtesham Ur

    2016-07-01

    Periodontal disease is associated with the destruction of periodontal tissues, along with other disorders/problems including inflammation of tissues and severe pain. This paper reports the synthesis of meloxicam (MX) immobilized biodegradable chitosan (CS)/poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) based electrospun (e-spun) fibers and films. Electrospinning was employed to produce drug loaded fibrous mats, whereas films were generated by solvent casting method. In-vitro drug release from materials containing varying concentrations of MX revealed that the scaffolds containing higher amount of drug showed comparatively faster release. During initial first few hours fast release was noted from membranes and films; however after around 5h sustained release was achieved. The hydrogels showed good swelling property, which is highly desired for soft tissue engineered implants. To investigate the biocompatibility of our synthesized materials, VERO cells (epithelial cells) were selected and cell culture results showed that these all materials were non-cytotoxic and also these cells were very well proliferated on these synthesized scaffolds. These properties along with the anti-inflammatory potential of our fabricated materials suggest their effective utilization in periodontital treatments. PMID:27127039

  1. Amperometric NOx-sensor for Combustion Exhaust Gas Control. Studies on transport properties and catalytic activity of oxygen permeable ceramic membranes

    International Nuclear Information System (INIS)

    The aim of the research described in this thesis is the development of a mixed conducting oxide layer, which can be used as an oxygen permselective membrane in an amperometric NOx sensor. The sensor will be used in exhaust gas systems. The exhaust gas-producing engine will run in the lean mix mode. The preparation of this sensor is carried out using screen-printing technology, in which the different layers of the sensor are applied successively. Hereafter, a co-firing step is applied in which all layers are sintered together. This co-firing step imposes several demands on the selection of materials. The design specifications of the sensor further include requirements concerning the operating temperature, measurement range and overall stability. The operating temperature of the sensor varies between 700 and 850C, enabling measurement of NOx concentrations between 50 and 1200 ppm with a measurement accuracy of 10 ppm. Concerning the stability of the sensor, it must withstand the exhaust gas atmosphere containing, amongst others, smoke, acids, abrasive particles and sulphur. Because of the chosen lean-mix engine concept, in which the fuel/air mixture switches continuously between lean (excess oxygen) and fat (excess fuel) mixtures, the sensor must withstand alternately oxidising and reducing atmospheres. Besides, it should be resistant to thermal shock and show no cross-sensitivity of NOx with other exhaust gas constituents like oxygen and hydrocarbons. The response time should be short, typically less than 500 ms. Because of the application in combustion engines of cars, the operational lifetime should be longer than 10 years. Demands on the mixed conducting oxide layer include the following ones. The layer should show minimal catalytic activity towards NOx-reduction. The oxygen permeability must be larger than 6.22 10-8 mol/cm2s at a layer thickness between 3-50 μm. Since the mixed conducting oxide layer is coated on the YSZ electrolyte embodiment, the two

  2. 基于膜射流乳化技术的TiO2大孔陶瓷制备方法研究%Preparation of Macroporous TiO2 Ceramic Based on Membrane Jet-flow Emulsification

    Institute of Scientific and Technical Information of China (English)

    景文珩; 吴守红; 薛业建; 金万勤; 邢卫红; 徐南平

    2007-01-01

    A novel method to prepare macroporous TiO2 ceramic, based on membrane emulsification was reported.To solve the paradox between the instability of nonaqueous emulsion and long emulsification time required by the membrane emulsification, a two-stage ceramic membrane jet-flow emulsification was proposed. Discussion was conducted on the evolution of droplet size with time, which followed the Ostwald ripening theory. And a monodispersed nonaqueous emulsion with an average droplet size of 1.6μm could be prepared. Using the emulsion as a template, TiO2 ceramics with an average pore size of 1.1μm were obtained. The material could be prospectively used for preparation of catalysts, adsorbents, and membranes.

  3. A low-cost mullite-titania composite ceramic hollow fiber microfiltration membrane for highly efficient separation of oil-in-water emulsion.

    Science.gov (United States)

    Zhu, Li; Chen, Mingliang; Dong, Yingchao; Tang, Chuyang Y; Huang, Aisheng; Li, Lingling

    2016-03-01

    Oil-in-water (O/W) emulsion is considered to be difficult to treat. In this work, a low-cost multi-layer-structured mullite-titania composite ceramic hollow fiber microfiltration membrane was fabricated and utilized to efficiently remove fine oil droplets from (O/W) emulsion. In order to reduce membrane cost, coal fly ash was effectively recycled for the first time to fabricate mullite hollow fiber with finger-like and sponge-like structures, on which a much more hydrophilic TiO2 layer was further deposited. The morphology, crystalline phase, mechanical and surface properties were characterized in details. The filtration capability of the final composite membrane was assessed by the separation of a 200 mg·L(-1) synthetic (O/W) emulsion. Even with this microfiltration membrane, a TOC removal efficiency of 97% was achieved. Dilute NaOH solution backwashing was used to effectively accomplish membrane regeneration (∼96% flux recovery efficiency). This study is expected to guide an effective way to recycle waste coal fly ash not only to solve its environmental problems but also to produce a high-valued mullite hollow fiber membrane for highly efficient separation application of O/W emulsion with potential simultaneous functions of pure water production and oil resource recovery. PMID:26748205

  4. Up-regulation of plasma membrane H+-ATPase under salt stress may enable Aeluropus littoralis to cope with stress

    Directory of Open Access Journals (Sweden)

    Hosna Olfatmiri

    2014-03-01

    Full Text Available Plasma membrane H+-ATPase is a major integral membrane protein with a role in various physiological processes including abiotic stress response. To study the effect of NaCl on the expression pattern of a gene encoding the plasma membrane H+-ATPase, an experiment was carried out in a completely random design with three replications. A pair of specific primers was designed based on the sequence of the gene encoding plasma membrane H+-ATPase in Aeluropus littoralis to amplify a 259 bp fragment from the target gene by PCR. A gene encoding actin was used as reference gene to normalize the expression level of the target gene. A pair of specific primers was designed to amplify a 157 bp fragment from the actin gene by PCR. Plants were treated with different concentrations of NaCl, 0, 50, 100, 150, 200, 250, 500 and 1000 mM, for two days. Our results showed that the expression level of the plasma membrane H+-ATPase gene increased dramatically at 500 mM and then decreased with increasing concentrations of NaCl. The results also indicated that the leaves of plants, were treated with high concentrations of NaCl changed morphologically, but those grown under low concentrations of NaCl as well as the control plants did not show morphological changes in their leaves. Our results suggest a relation between morphological changes of treated plants and the expression level of the plasma membrane H+-ATPase gene in Aeluropus littoralis.

  5. Experimental and Modeling Studies of the Methane Steam Reforming Reaction at High Pressure in a Ceramic Membrane Reactor

    OpenAIRE

    Hacarlioglu, Pelin

    2007-01-01

    This dissertation describes the preparation of a novel inorganic membrane for hydrogen permeation and its application in a membrane reactor for the study of the methane steam reforming reaction. The investigations include both experimental studies of the membrane permeation mechanism and theoretical modeling of mass transfer through the membrane and simulation of the membrane reactor with 1-D and 2-D models. A hydrothermally stable and hydrogen selective membrane composed of silica and a...

  6. Oxygen permeability of transition metal-containing La(Sr,PrGa(MgO3-δ ceramic membranes

    Directory of Open Access Journals (Sweden)

    Frade, J. R.

    2004-08-01

    Full Text Available Acceptor-type doping of perovskite-type La1-xSrxGa0.80-yMgyM0.20O3-δ (x = 0-0.20, y = 0.15-0.20, M = Fe, Co, Ni leads to significant enhancement of ionic conductivity and oxygen permeability due to increasing oxygen vacancy concentration. The increase in strontium and magnesium content is accompanied, however, with increasing role of surface exchange kinetics as permeation-limiting factor. At temperatures below 1223 K, the oxygen permeation fluxes through La(SrGa(Mg,MO3-δ membranes with thickness less than 1.5 mm are predominantly limited by the exchange rates at membrane surface. The oxygen transport in transition metal-containing La(SrGa(MgO3-δ ceramics increase in the sequence Co El dopado aceptor de cerámicas tipo perovskita La1-xSrxGa0.80-yMgyM0.20O3-δ (x = 0-0.20, y = 0.15-0.20, M = Fe, Co, Ni da lugar a una mejora significativa de la conductividad iónica y de la permeabilidad al oxígeno debido al aumento de la concentración de vacantes de oxígeno. Sin embargo, el aumento de la cantidad de estroncio y magnesio viene acompañado de un aumento de la participación de las cinéticas de intercambio superficial como factor limitante de la permeabilidad. A temperaturas por debajo de 1223 K la permeabilidad al flujo de oxígeno a través de las membranas de La(SrGa(Mg,MO3-δ con espesor menor de 1.5 mm está limitado principalmente por las velocidades de intercambio en la superficie de la membrana. El transporte de oxígeno en las cerámicas La(SrGa(MgO3-δ que contienen M aumenta en la secuencia Co < Fe < Ni. La conductividad iónica en estas fases es, sin embargo, menor que en la de los compuestos La1-xSrxGa1-yMgyO3-δ. El mayor nivel de permeabilidad de oxígeno, comparable a la de las fases basadas en La(SrFe(CoO3 y La2NiO4, se observa para las membranas de La0.90Sr0.10Ga0.65Mg0.15Ni0.20O3-δ. Los coeficientes de dilatación térmica medios de las cerámicas La(SrGa(Mg,MO3-δ en aire son del orden de (11.6–18.4 × 10-6 K-1 a 373

  7. Membraner

    DEFF Research Database (Denmark)

    Bach, Finn

    2009-01-01

    Notatet giver en kort introduktion til den statiske virkemåde af membraner og membrankonstruktioner......Notatet giver en kort introduktion til den statiske virkemåde af membraner og membrankonstruktioner...

  8. Separation membrane development

    Energy Technology Data Exchange (ETDEWEB)

    Lee, M.W. [Savannah River Technology Center, Aiken, SC (United States)

    1998-08-01

    A ceramic membrane has been developed to separate hydrogen from other gases. The method used is a sol-gel process. A thin layer of dense ceramic material is coated on a coarse ceramic filter substrate. The pore size distribution in the thin layer is controlled by a densification of the coating materials by heat treatment. The membrane has been tested by permeation measurement of the hydrogen and other gases. Selectivity of the membrane has been achieved to separate hydrogen from carbon monoxide. The permeation rate of hydrogen through the ceramic membrane was about 20 times larger than Pd-Ag membrane.

  9. Nanoporous membranes for enzyme-based organophosphate biosensors: Characterizating bio-ceramic conjugation, porosity, and activity in stable soil-gel ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Schoeniger, J.S.; Singh, A.K.; Volponi, J. [Sandia National Labs., Livermore, CA (United States)] [and others

    1997-12-31

    Biosensors for organophosphates in solution may be constructed by monitoring the activities of acetylcholine esterase (AchE) or organophosphate hydrolases (OPHs) immoblized on pH-sensitive field-effect transistors (FETs). In order to construct stable sensors with control over the surface catalytic activity and transport properties, SiO2 or Si3N4 surfaces were coated with highly porous, heat-stabilized sol-gel coatings. Surface porosity was characterized using SEM and AFM. AchE or OPH were covalently attached to the porous ceramics using several different conjugation chemistries and enzyme stabilization techniques. Properties such as covalent vs. non-covalent attachment, specific activity, and robustness of enzyme activity were characterized. Data on the effect of surface modifications on sensor performance will also be presented.

  10. Cationic Polymer Intercalation into the Lipid Membrane Enables Intact Polyplex DNA Escape from Endosomes for Gene Delivery.

    Science.gov (United States)

    Vaidyanathan, Sriram; Chen, Junjie; Orr, Bradford G; Banaszak Holl, Mark M

    2016-06-01

    Developing improved cationic polymer-DNA polyplexes for gene delivery requires improved understanding of DNA transport from endosomes into the nucleus. Using a FRET-capable oligonucleotide molecular beacon (OMB), we monitored the transport of intact DNA to cell organelles. We observed that for effective (jetPEI) and ineffective (G5 PAMAM) vectors, the fraction of cells displaying intact OMB in the cytosol (jetPEI ≫ G5 PAMAM) quantitatively predicted the fraction expressing transgene (jetPEI ≫ G5 PAMAM). Intact OMB delivered with PAMAM and confined to endosomes could be released to the cytosol by the subsequent addition of L-PEI, with a corresponding 10-fold increase in transgene expression. These results suggest that future vector development should optimize vectors for intercalation into, and destabilization of, the endosomal membrane. Finally, the study highlights a two-step strategy in which the pDNA is loaded in cells using one vector and endosomal release is mediated by a second agent. PMID:27111496

  11. Effect of Porosity and Concentration Polarization on Electrolyte Diffusive Transport Parameters through Ceramic Membranes with Similar Nanopore Size

    Directory of Open Access Journals (Sweden)

    Virginia Romero

    2014-08-01

    Full Text Available Diffusive transport through nanoporous alumina membranes (NPAMs produced by the two-step anodization method, with similar pore size but different porosity, is studied by analyzing membrane potential measured with NaCl solutions at different concentrations. Donnan exclusion of co-ions at the solution/membrane interface seem to exert a certain control on the diffusive transport of ions through NPAMs with low porosity, which might be reduced by coating the membrane surface with appropriated materials, as it is the case of SiO2. Our results also show the effect of concentration polarization at the membrane surface on ionic transport numbers (or diffusion coefficients for low-porosity and high electrolyte affinity membranes, which could mask values of those characteristic electrochemical parameters.

  12. Preparation of Monodispersed O/W Emulsion by Ceramic External Membrane Emulsification System--Preliminary Study on Integrated Ceramic Membrane Emulsification Reactor%陶瓷膜乳化系统制备单分散乳状液的研究--集成式膜乳化反应器的前期研究

    Institute of Scientific and Technical Information of China (English)

    景文珩; 吴俊; 邢卫红; 徐南平

    2004-01-01

    A new reactor with integrated conventional slurry stirred reactor and ceramic external membrane emulsification system, was introduced in this paper. Toluene and toluene containing surfactant was separately used as dispersed phase for preparation of emulsions. Two kinds of emulsions were prepared and compared. The volume average sizes of prepared emulsions were 3.53μm and 3.6μm respectively. The results showed that the droplet sizes of two kinds of emulsions were similar, but the monodispersed emulsion was only obtained with addition of surfactant into the dispersed phase.

  13. Optimization of O3 as Pre-Treatment and Chemical Enhanced Backwashing in UF and MF Ceramic Membranes for the Treatment of Secondary Wastewater Effluent and Red Sea Water

    KAUST Repository

    Herrera, Catalina

    2011-12-12

    Ceramic membranes have proven to have many advantages over polymeric membranes. Some of these advantages are: resistance against extreme pH, higher permeate flux, less frequent chemical cleaning, excellent backwash efficiency and longer lifetime. Other main advantage is the use of strong chemical agent such as Ozone (O3), to perform membrane cleaning. Ozone has proven to be a good disinfection agent, deactivating bacteria and viruses. Ozone has high oxidation potential and high reactivity with natural organic matter (NOM). Several studies have shown that combining ozone to MF/UF systems could minimize membrane fouling and getting higher operational fluxes. This work focused on ozone – ceramic membrane filtration for treating wastewater effluent and seawater. Effects of ozone as a pre – treatment or chemical cleaning with ceramic membrane filtration were identified in terms of permeate flux and organic fouling. Ozonation tests were done by adjusting O3 dose with source water, monitoring flux decline and membrane fouling. Backwashing availability and membrane recovery rate were also analyzed. Two types of MF/UF ceramics membranes (AAO and TAMI) were used for this study. When ozone dosage was higher in the source water, membrane filtration improved in performance, resulting in a reduced flux decline. In secondary wastewater effluent, raw source water declined up to 77% of normalized flux, while with O3 as pre – treatment, source water at its higher O3 dose, flux decreased only 33% of normalized flux. For seawater, membrane performance increase from declining to 37% of its final normalized flux to 21%, when O3 as a pre – treatment was used. Membrane recovery rate also improved even with low O3 dose, as an example, with 8 mg/L irreversible fouling decreases from 58% with no ozone addition to 29% for secondary wastewater effluent treatment. For seawater treatment, irreversible fouling decreased from 37% with no ozone addition to 21% at 8 mg/L, proving ozone is a

  14. Synthesis of ceramic hollow fiber supported zeolitic imidazolate framework-8 (ZIF-8) membranes with high hydrogen permeability

    KAUST Repository

    Pan, Yichang

    2012-12-01

    Purification and recovery of hydrogen from hydrocarbons in refinery streams in the petrochemical industry is an emerging research field in the study of membrane gas separation. Hollow fiber membrane modules can be easily implemented into separation processes at the industrial scale. In this report, hollow yttria-stabilized zirconia (YSZ) fiber-supported zeolitic imidazole framework-8 (ZIF-8) membranes were successfully prepared using a mild and environmentally friendly seeded growth method. Our single-component permeation studies demonstrated that the membrane had a very high hydrogen permeance (~15×10 -7mol/m 2sPa) and an ideal selectivity of H 2/C 3H 8 of more than 1000 at room temperature. This high membrane permeability and selectivity caused serious concentration polarization in the separation of H 2/C 3H 8 mixtures, which led to almost 50% drop in both the H 2 permeance and the separation factor. Enhanced mixing on the feed side could reduce the effect of the concentration polarization. Our experimental data also indicated that the membranes had excellent reproducibility and long-term stability, indicating that the hollow fiber-supported ZIF-8 membranes developed in this study have great potential in industry-scale separation of hydrogen. © 2012 Elsevier B.V.

  15. Application of graphite-based sacrificial layers for fabrication of LTCC (low temperature co-fired ceramic) membranes and micro-channels

    Science.gov (United States)

    Birol, H.; Maeder, T.; Ryser, P.

    2007-01-01

    Fabrication of sensors and micro-fluidic structures from low temperature co-fired ceramic (LTCC) sheets is a growing interest in the micro-packaging community. Such devices usually have inner cavities, whose production is quite complicated. The most elegant method to build such structures so far achieved is by a fugitive phase that is introduced into the multilayer and removed during firing. This paper, therefore, is aimed to introduce the graphite-based sacrificial paste developed for this purpose, and it is constructed in two sections: (i) selection of paste and determination of LTCC open-porosity elimination temperature, and (ii) fabrication and characterization of pressure sensitive LTCC membranes. In the former section, it is shown that increased heating rates (and decreasing tape thickness) shift the open porosity elimination temperature of LTCC by 20 °C, which is small compared to the shift of graphite oxidation temperature (about 100 °C). In the latter section, three parameters affecting the balance between the graphite oxidation and LTCC sintering are studied: heating rate, graphite phase thickness and width of the membrane inlet/outlet channels. As expected, larger heating rates and narrow inlet/outlet channels are found to hinder the oxidation of graphite and evacuation of the resulting products, which results in swollen membranes. Large graphite thickness, through the increased channel height, results in lower swelling in spite of the larger amount of graphite to be oxidized. Membranes with low swelling are found to exhibit excellent pressure sensing characteristics, whereas those with high swelling display hysteretic behavior.

  16. Time-dependent growth of ceramic supported NaA membranes : a morphological and permeation based study / Jaco Zah

    OpenAIRE

    Zah, Jaco

    2006-01-01

    Based on its ideal aperture size (4.1 A) and hydrophilic framework, the NaA membrane possesses significant potential in the separation of many industrially important gaseous and liquid mixtures. In the local South African context, the foreseeable production of affordable, high-purity ethanol in the alternative fuel market exemplifies one such a possibility. However, there are still certain aspects to the composite NaA membrane that are not clearly understood. These include the tim...

  17. Effect of interactions between Co(2+) and surface goethite layer on the performance of α-FeOOH coated hollow fiber ceramic ultrafiltration membranes.

    Science.gov (United States)

    Zhu, Zhiwen; Zhu, Li; Li, Jianrong; Tang, Jianfeng; Li, Gang; Hsieh, Yi-Kong; Wang, TsingHai; Wang, Chu-Fang

    2016-03-15

    The consideration of water energy nexus inspires the environmental engineering community to pursue a more sustainable strategy in the wastewater treatment. One potential response would be to enhance the performance of the low-pressure driven filtration system. To reach this objective, it is essential to have a better understanding regarding the surface interaction between the target substance and the surface of membrane. In this study, the hollow fiber ceramic membranes were coated with a goethite layer in order to enhance the Co(2+) rejection. Experimental results indicate that higher Co(2+) rejections are always accompanied with the significant reduction in the permeability. Based on the consideration of electroviscous effect, the surface interactions including the induced changes in viscosity, pore radius and Donnan effect in the goethite layer are likely responsible for the pH dependent behaviors in the rejection and permeability. These results could be valuable references to develop the filtration system with high rejection along with acceptable degree of permeability in the future. PMID:26704473

  18. Engineering Development of Ceramic Membrane Reactor System for Converting Natural Gas to Hydrogen and Synthesis Gas for Liquid Transportation Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Air Products and Chemicals

    2008-09-30

    An Air Products-led team successfully developed ITM Syngas technology from the concept stage to a stage where a small-scale engineering prototype was about to be built. This technology produces syngas, a gas containing carbon monoxide and hydrogen, by reacting feed gas, primarily methane and steam, with oxygen that is supplied through an ion transport membrane. An ion transport membrane operates at high temperature and oxygen ions are transported through the dense membrane's crystal lattice when an oxygen partial pressure driving force is applied. This development effort solved many significant technical challenges and successfully scaled-up key aspects of the technology to prototype scale. Throughout the project life, the technology showed significant economic benefits over conventional technologies. While there are still on-going technical challenges to overcome, the progress made under the DOE-funded development project proved that the technology was viable and continued development post the DOE agreement would be warranted.

  19. CO2 SELECTIVE CERAMIC MEMBRANE FOR WATER-GAS SHIFT REACTION WITH CONCOMITANT FOR THE RECOVERY OF CO2

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2002-05-08

    The reversibility study using TGA/MS has been completed. Our result shows that the hydrotalcite material we proposed exhibits a high degree of CO{sub 2} reversibility. In addition, at higher temperatures (>200 C), insignificant adesorption of water was observed. Combining these results, we conclude that the hydrotalcite we choose is an ideal candidate material for high temperature gas separations requiring hydrothermal stability. We also have focused on the optimization of membrane synthesis. The gel formed after combining the reagents is an ideal precursor for deposition within the porous membrane based upon the Al/Mg ratio analysis and impurity leaching study. Finally, we experimentally verify the crystal growth temperature ranging from 100 to 150 C. The crystal growth is also highly dependent upon the time. Our study shows a general growth pattern from 0 to >4 hours. In the next quarter, we will utilize the information obtained here to initiate the optimization of membrane synthesis.

  20. 陶瓷膜处理啤酒洗瓶废碱液的膜污染和清洗再生%MEMBRANE POLLUTION AND CLEANING REGENERATION OF TREATING THE BOTTLE WASHING WASTE ALKALI LIQUID OF BEER INDUSTRY BY CERAMIC MEMBRANE

    Institute of Scientific and Technical Information of China (English)

    傅金祥; 路京鹏; 唐玉兰; 张荣新; 周东旭

    2012-01-01

    研究了陶瓷膜过滤啤酒洗瓶废碱液膜污染机理,提出了相应的清洗再生方案。对比研究了硝酸、盐酸、次氯酸钠、三聚磷酸钠4种清洗剂单独使用和复合使用的清洗再生效果。试验表明:0.20%硝酸+0.55%次氯酸钠+0.15%三聚磷酸钠复合清洗再生陶瓷膜,膜通量恢复率在85%以上。陶瓷膜连续运行两个月,清洗再生效果稳定,具有工程实用价值。%Membrane pollution mechanism had been researched in filtering the bottle washing waste alkali liquid by ceramic membrane and the corresponding cleaning regeneration schemes had also been put forward.The cleaning effect of nitric acid,hydrochloric acid,sodium hypochlorite and sodium tripoly phosphate on the ceramic membrane had been researched.Experiments show that the membrane flux recovery rate is more than 85% by the ceramic membrane of 0.20% nitric acid+0.55% sodium hypochlorite+0.15% sodium tripoly phosphate.Ceramic membrane is operated continuously in two months,the cleaning effect is stable and has practical value.

  1. A high performance ceramic-polymer separator for lithium batteries

    Science.gov (United States)

    Kumar, Jitendra; Kichambare, Padmakar; Rai, Amarendra K.; Bhattacharya, Rabi; Rodrigues, Stanley; Subramanyam, Guru

    2016-01-01

    A three-layered (ceramic-polymer-ceramic) hybrid separator was prepared by coating ceramic electrolyte [lithium aluminum germanium phosphate (LAGP)] over both sides of polyethylene (PE) polymer membrane using electron beam physical vapor deposition (EB-PVD) technique. Ionic conductivities of membranes were evaluated after soaking PE and LAGP/PE/LAGP membranes in a 1 Molar (1M) lithium hexafluroarsenate (LiAsF6) electrolyte in ethylene carbonate (EC), dimethyl carbonate (DMC) and ethylmethyl carbonate (EMC) in volume ratio (1:1:1). Scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques were employed to evaluate morphology and structure of the separators before and after cycling performance tests to better understand structure-property correlation. As compared to regular PE separator, LAGP/PE/LAGP hybrid separator showed: (i) higher liquid electrolyte uptake, (ii) higher ionic conductivity, (iii) lower interfacial resistance with lithium and (iv) lower cell voltage polarization during lithium cycling at high current density of 1.3 mA cm-2 at room temperature. The enhanced performance is attributed to higher liquid uptake, LAGP-assisted faster ion conduction and dendrite prevention. Optimization of density and thickness of LAGP layer on PE or other membranes through manipulation of PVD deposition parameters will enable practical applications of this novel hybrid separator in rechargeable lithium batteries with high energy, high power, longer cycle life, and higher safety level.

  2. Research Progress on the Preparation of Ceramic Hollow Fiber Membranes by Nonsolvent Induced Phase Separation%浸渍相转化法制备陶瓷中空纤维膜的研究进展

    Institute of Scientific and Technical Information of China (English)

    刘朋超; 马敬红; 杨曙光; 龚静华; 徐坚

    2012-01-01

    浸渍相转化法可以制备非对称结构的陶瓷中空纤维膜.本文讨论了陶瓷中空纤维膜的发展情况,并着重探讨了各因素对膜孔结构的影响.大量陶瓷粉体存在情况下的相转化机理,孔结构与力学强度的平衡问题,是目前需要重点关注的两个问题.有效调节孔结构,保证其力学性能可以实现陶瓷中空纤维膜在分离和纯化、固体氧化物燃料电池、膜催化器和膜反应器等方面的广泛应用.%Ceramic hollow fiber membranes (CHFM) with an asymmetric structure can be fabricated by the method nonsolvent induced phase separation (NIPS). The paper reviews the progress and tendency of the ceramic hollow fiber membranes using NIPS technic, especially on the influence of factors on the structure of hollow membranes. The discussion on the mechanism of phase inversion in the systems containing much ceramic powders, with the balance between porous structure and mechanical strength, are two important issues of requiring concern. Through structure's controlled effectively and mechanical strength preserved, hollow fiber membranes can be widely applied in the fields of separation and purification, solid oxide fuel cell (SOFC), membrane contactors and reactors.

  3. 超声在陶瓷膜处理乳化含油废水中的作用研究%Effect of Ultrasound on the Treatment of Emulsification Wastewater by Ceramic Membranes

    Institute of Scientific and Technical Information of China (English)

    舒莉; 邢卫红; 徐南平

    2007-01-01

    Ultrasonic field was applied in the treatment of oil emulsification wastewater by ZrO2 ceramic membrane. The permeate flux,rejection ratio in the filtration process and recovery ratio of flux in the membrane cleaning process were measured. Great improvement in the permeate flux and rejection ratio have been observed for the membrane process enhanced by the ultrasonic field. The permeate flux of water through the membrane was about were 8W of ultrasonic power,7cm of ultrasonic probe length introduced into the membrane channel and the same ultrasonic radiation direction as the wastewater flow. The resistance of the membrane process was compared between the cases with and without ultrasound,and the total resistance was reduced 68% by the use of ultrasound.Four methods including water cleaning,water cleaning under sonication,chemical cleaning and chemical cleaning under sonication were used to recover membrane flux. It was found that the flux recovery ratio increased with the increase of ultrasonic cleaning power. In addition,the use of chemical agents combining with ultrasonic irradiation showed a synergistic effect,which resulted in the highest cleaning efficiency and the shorter cleaning time.

  4. Enabling the intestinal absorption of highly polar antiviral agents: ion-pair facilitated membrane permeation of zanamivir heptyl ester and guanidino oseltamivir.

    Science.gov (United States)

    Miller, Jonathan M; Dahan, Arik; Gupta, Deepak; Varghese, Sheeba; Amidon, Gordon L

    2010-08-01

    Antiviral drugs often suffer from poor intestinal permeability, preventing their delivery via the oral route. The goal of this work was to enhance the intestinal absorption of the low-permeability antiviral agents zanamivir heptyl ester (ZHE) and guanidino oseltamivir (GO) utilizing an ion-pairing approach, as a critical step toward making them oral drugs. The counterion 1-hydroxy-2-naphthoic acid (HNAP) was utilized to enhance the lipophilicity and permeability of the highly polar drugs. HNAP substantially increased the log P of the drugs by up to 3.7 log units. Binding constants (K(11(aq))) of 388 M(-1) for ZHE-HNAP and 2.91 M(-1) for GO-HNAP were obtained by applying a quasi-equilibrium transport model to double-reciprocal plots of apparent octanol-buffer distribution coefficients versus HNAP concentration. HNAP enhanced the apparent permeability (P(app)) of both compounds across Caco-2 cell monolayers in a concentration-dependent manner, as substantial P(app) (0.8-3.0 x 10(-6) cm/s) was observed in the presence of 6-24 mM HNAP, whereas no detectable transport was observed without counterion. Consistent with a quasi-equilibrium transport model, a linear relationship with slope near 1 was obtained from a log-log plot of Caco-2 P(app) versus HNAP concentration, supporting the ion-pair mechanism behind the permeability enhancement. In the rat jejunal perfusion assay, the addition of HNAP failed to increase the effective permeability (P(eff)) of GO. However, the rat jejunal permeability of ZHE was significantly enhanced by the addition of HNAP in a concentration-dependent manner, from essentially zero without HNAP to 4.0 x 10(-5) cm/s with 10 mM HNAP, matching the P(eff) of the high-permeability standard metoprolol. The success of ZHE-HNAP was explained by its >100-fold stronger K(11(aq)) versus GO-HNAP, making ZHE-HNAP less prone to dissociation and ion-exchange with competing endogenous anions and able to remain intact during membrane permeation. Overall, this

  5. Membranes for energy conversion

    Energy Technology Data Exchange (ETDEWEB)

    Peinemann, K.V.; Pereira Nunes, S. (eds.) [GKSS-Forschungszentrum Geesthacht GmbH (Germany)

    2008-07-01

    This volume contains the following chapters: 1. Sulfonated poly(arylether)-type polymers as proton exchange membranes: Synthesis and performance; 2. Polyimide ionomer membranes for PEFCs and DMFCs; 3. Membranes for high temperature PEFC based on acid-doped polybenzimidazoles; 4. Membrane for medium temperature PEFC based on Nafion filled with layered metal phosphates and phosphonates 5. Composite membranes for high temperature direct methanol fuel cells; 6. Dense ceramic membranes for hydrogen separation; 7. Membranes in energy systems with CO{sub 2} capture 8. Palladium membranes for hydrogen separation; 9. Membranes for power generation by pressure retarded osmosis.

  6. Treatment of cosmetic effluent in different configurations of ceramic UF membrane based bioreactor: Toxicity evaluation of the untreated and treated wastewater using catfish (Heteropneustes fossilis).

    Science.gov (United States)

    Banerjee, Priya; Dey, Tanmoy Kumar; Sarkar, Sandeep; Swarnakar, Snehasikta; Mukhopadhyay, Aniruddha; Ghosh, Sourja

    2016-03-01

    Extensive usage of pharmaceutical and personal care products (PPCPs) and their discharge through domestic sewage have been recently recognized as a new generation environmental concern which deserves more scientific attention over the classical environmental pollutants. The major issues of this type of effluent addressed in this study were its colour, triclosan and anionic surfactant (SDS) content. Samples of cosmetic effluent were collected from different beauty treatment salons and spas in and around Kolkata, India and treated in bioreactors containing a bacterial consortium isolated from activated sludge samples collected from a common effluent treatment plant. Members of the consortium were isolated and identified as Klebsiella sp., Pseudomonas sp., Salmonella sp. and Comamonas sp. The biotreated effluent was subjected to ultrafiltration (UF) involving indigenously prepared ceramic membranes in both side-stream and submerged mode. Analysis of the MBR treated effluent revealed 99.22%, 98.56% and 99.74% removal of colour, triclosan and surfactant respectively. Investigation of probable acute and chronic cyto-genotoxic potential of the untreated and treated effluents along with their possible participation in triggering oxidative stress was carried out with Heteropneustes fossilis (Bloch). Comet formation recorded in both liver and gill cells and micronucleus count in peripheral erythrocytes of individuals exposed to untreated effluent increased with duration of exposure and was significantly higher than those treated with UF permeates which in turn neared control levels. Results of this study revealed successful application of the isolated bacterial consortium in MBR process for efficient detoxification of cosmetic effluent thereby conferring the same suitable for discharge and/or reuse. PMID:26714296

  7. Structural Ceramics

    Science.gov (United States)

    1986-01-01

    This publication is a compilation of abstracts and slides of papers presented at the NASA Lewis Structural Ceramics Workshop. Collectively, these papers depict the scope of NASA Lewis' structural ceramics program. The technical areas include monolithic SiC and Si3N4 development, ceramic matrix composites, tribology, design methodology, nondestructive evaluation (NDE), fracture mechanics, and corrosion.

  8. Advanced Ceramics

    International Nuclear Information System (INIS)

    The First Florida-Brazil Seminar on Materials and the Second State Meeting about new materials in Rio de Janeiro State show the specific technical contribution in advanced ceramic sector. The others main topics discussed for the development of the country are the advanced ceramic programs the market, the national technic-scientific capacitation, the advanced ceramic patents, etc. (C.G.C.)

  9. Effect of Different Pore Sizes of Ceramic Microfiltration Membrane on the Removing Rate of Bacteria of Pomegranate Juice%不同孔径陶瓷微滤膜对石榴汁除菌效果的影响

    Institute of Scientific and Technical Information of China (English)

    艾提亚古丽·买热甫; 热合满·艾拉; 张敬

    2012-01-01

    以新疆和田酸石榴为原料加工石榴汁,采用不同孔径的陶瓷微滤膜对石榴汁进行除菌过滤,对比不同孔径(0.10、0.22、0.45 μm)微滤膜的膜通量、石榴汁除菌率、营养成分含量及色值等指标的变化,确定适于石榴汁过滤除菌的陶瓷微滤膜的孔径与最佳工艺参数.结果表明,用于石榴汁过滤除菌的陶瓷微滤膜的适宜孔径为0.22 μm;最佳工艺参数为:过滤压力0.20 MPa,料液温度20℃.在此条件下,陶瓷微滤膜过滤的石榴汁可保持较高的膜通量,有效去除果汁中的悬浮物和有害微生物,较好地保留营养成分,石榴汁在120d储藏过程中的色泽变化轻微.陶瓷微滤膜过滤除菌可以作为一种除菌工艺代替石榴汁加工中的传统热杀菌工艺.%In this experiment, the Xinjiang Hetian acid pomegranate was used as raw materials, pomegranate juice was filtered for bacteria removing by using different pore sizes of ceramic microfiltration membrane, and comparing the changes of membrane flux, bacteria removing rate, nutritional contents and colour value of pomegranate juice with different pore sizes (0.10, 0.22, 0.45 μm) of ceramic microfiltration membrane, and the suitable pore size of ceramic microfiltration membrane and optimum technological parameter of bacteria removing of pomegranate juice were determined. The results indicated that, the suitable pore size of ceramic microfiltration membrane of bacteria removing of pomegranate juice was 0.22 μm. Optimum technological parameters were as follows: the filtering pressure was 0.20 MPa, the feed temperature was 20 ℃. Under these conditions, the pomegranate juice could keep high membrane flux, and the suspensions and harmful bacteria in juice could be removel effectively, the nutritional contents could be kept better, and the change of pomegranate juice colour during storage time (120 d) was not significant. The removing bacteria technology of ceramic microfiltration membrane

  10. Performance and mechanisms for the removal of phthalates and pharmaceuticals from aqueous solution by graphene-containing ceramic composite tubular membrane coupled with the simultaneous electrocoagulation and electrofiltration process.

    Science.gov (United States)

    Yang, Gordon C C; Chen, Ying-Chun; Yang, Hao-Xuan; Yen, Chia-Heng

    2016-07-01

    In this study, commonly detected emerging contaminants (ECs) in water, including di-n-butyl phthalate (DnBP), di(2-ethylhexyl) phthalate (DEHP), cephalexin (CLX), sulfamethoxazole (SMX) and caffeine (CAF), were selected as the target contaminants. A lab-prepared graphene-containing ceramic composite tubular membrane (TGCCM) coupled with the simultaneous electrocoagulation and electrofiltration process (EC/EF) in crossflow filtration mode was used to remove target contaminants in model solution. Meanwhile, a comparison of the removal efficiency was made among various tubular composite membranes reported, including carbon fibers/carbon/alumina composite tubular membrane (TCCACM), titania/alumina composite tubular membrane (TTACM) and alumina tubular membrane (TAM). The results of this study showed that the removal efficiencies for DnBP and DEHP were 99%, whereas 32-97% for cephalexin (CLX), sulfamethoxazole (SMX) and caffeine (CAF). In this work the mechanisms involved in removing target ECs were proposed and their roles in removing various ECs were also discussed. Further, two actual municipal wastewaters were treated to evaluate the applicability of the aforementioned treatment technology (i.e., TGCCM coupled with EC/EF) to various aqueous solutions in the real world. PMID:27131034

  11. Joining of ceramic Ba0.5Sr0.5Co0.8Fe0.2O3 membranes for oxygen production to high temperature alloys

    DEFF Research Database (Denmark)

    Kiebach, Wolff-Ragnar; Engelbrecht, Kurt; Kwok, Kawai;

    2016-01-01

    The possibility of joining dense ceramic BCSF tubular membranes to metal alloys using a silver braze was investigated. Four different alloys (Crofer 22 APU (R), Kanthal APM (R), Haynes 214 (R) and EN 1.4841) were considered and the influence of their oxide scale stability/reactivity and their the......The possibility of joining dense ceramic BCSF tubular membranes to metal alloys using a silver braze was investigated. Four different alloys (Crofer 22 APU (R), Kanthal APM (R), Haynes 214 (R) and EN 1.4841) were considered and the influence of their oxide scale stability...

  12. 用于TS-1催化剂回收的陶瓷膜污染机理%The Fouling Mechanism of Ceramic Membranes Used for Recovering TS-1 Catalysts

    Institute of Scientific and Technical Information of China (English)

    仲兆祥; 李冬燕; 刘馨; 邢卫红; 徐南平

    2009-01-01

    Ceramic ultrafiltration membranes were used to separate titanium silicalite-1 (TS-1) catalysts from the slurry of catalytic ammoximation of cyclohexanone to oxime. Silica was shown to have a great effect on membrane fouling in the alkaline environment of this system. In the ammoximation system, there are three main silica sources, which are residual silica on the catalyst particles surface during preparation, silica dissolved from TS-1 catalyst par-ticles by ammonia solvent, and silica sol added into the reaction slurry to inhibit the dissolution erosion of the TS-1 catalyst. The silica dissolved by ammonia has been proved to influence membrane fouling most among the three silica sources. This was because the amount of silica dissolved by ammonia was the largest, and the polymerization of silica monomers at high concentration caused colloid particles formation, which led to a dense cake layer depos-iting on the membrane surface. Meanwhile, the size reduction of catalyst particles caused by alkaline dissolution also increased specific resistances of cake layers.

  13. Ceramic joining

    Energy Technology Data Exchange (ETDEWEB)

    Loehman, R.E. [Sandia National Lab., Albuquerque, NM (United States)

    1996-04-01

    This paper describes the relation between reactions at ceramic-metal interfaces and the development of strong interfacial bonds in ceramic joining. Studies on a number of systems are described, including silicon nitrides, aluminium nitrides, mullite, and aluminium oxides. Joints can be weakened by stresses such as thermal expansion mismatch. Ceramic joining is used in a variety of applications such as solid oxide fuel cells.

  14. Surface analysis of mixed-conducting ferrite membranes by the conversion-electron Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Conversion-electron Moessbauer spectroscopy analysis of iron surface states in the dense ceramic membranes made of 57Fe-enriched SrFe0.7Al0.3O3-δ perovskite, shows no traces of reductive decomposition or carbide formation in the interfacial layers after operation under air/CH4 gradient at 1173 K, within the limits of experimental uncertainty. The predominant trivalent state of iron cations at the membrane permeate-side surface exposed to flowing dry methane provides evidence of the kinetic stabilization mechanism, which is only possible due to slow oxygen-exchange kinetics and enables long-term operation of the ferrite-based ceramic reactors for natural gas conversion. At the membrane feed-side surface exposed to air, the fractions of Fe4+ and Fe3+ are close to those in the powder equilibrated at atmospheric oxygen pressure, suggesting that the exchange limitations to oxygen transport are essentially localized at the partially reduced surface. - Graphical Abstract: Conversion-electron Moessbauer spectroscopy analysis of dense ceramic membranes made of 57Fe-enriched SrFe0.7Al0.3O3-δ perovskite, shows no reductive decomposition in thin interfacial layers after testing under air/CH4 gradient, enabling stable operation of the ferrite-based ceramic reactors for partial oxidation of methane. Highlights: → Conversion-electron Moessbauer spectroscopy is used for mixed-conducting membranes. → No decomposition is detected in the membrane surface layers under air/CH4 gradient. → Due to kinetic stabilization, Fe3+ states prevail at the surface exposed to methane. → Transmission Moessbauer spectra show perovskite decomposition on equlibration in CH4. → Ferrite-based ceramic reactors can stably operate under air/CH4 gradient.

  15. Ceramic Methyltrioxorhenium

    CERN Document Server

    Herrmann, R; Eickerling, G; Helbig, C; Hauf, C; Miller, R; Mayr, F; Krug von Nidda, H A; Scheidt, E W; Scherer, W; Herrmann, Rudolf; Troester, Klaus; Eickerling, Georg; Helbig, Christian; Hauf, Christoph; Miller, Robert; Mayr, Franz; Nidda, Hans-Albrecht Krug von; Scheidt, Ernst-Wilhelm; Scherer, Wolfgang

    2006-01-01

    The metal oxide polymeric methyltrioxorhenium [(CH3)xReO3] is an unique epresentative of a layered inherent conducting organometallic polymer which adopts the structural motifs of classical perovskites in two dimensions (2D) in form of methyl-deficient, corner-sharing ReO5(CH3) octahedra. In order to improve the characteristics of polymeric methyltrioxorhenium with respect to its physical properties and potential usage as an inherentconducting polymer we tried to optimise the synthetic routes of polymeric modifications of 1 to obtain a sintered ceramic material, denoted ceramic MTO. Ceramic MTO formed in a solvent-free synthesis via auto-polymerisation and subsequent sintering processing displays clearly different mechanical and physical properties from polymeric MTO synthesised in aqueous solution. Ceramic MTO is shown to display activated Re-C and Re=O bonds relative to MTO. These electronic and structural characteristics of ceramic MTO are also reflected by a different chemical reactivity compared with its...

  16. A model to enable indirect manufacturing options transactions between organisations: An application to the ceramic industry; Modelo de trasvase indirecto de opciones de fabricacion entre organizaciones: Una aplicacion a la industria ceramica

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Rodriguez, R.; Gomez-Gasquet, P.; Oltra-Badenes, R. F.

    2014-07-01

    In the current competitive contexts, it is widely accepted and proved that inter-enterprise collaboration lead in many occasions to better results. The Spanish ceramic industry must improve, dropping its manufacturing costs in order to be able to compete with low cost products coming from Asia. In this sense, this work presents the main results obtained from applying an innovative model, which facilitates the transfer of manufacturing options between two ceramic enterprises that share a common supplier in the scenario where one of them needs more manufacturing capacity than the one booked according to its demand forecast and the another need less. Then, some decisional mechanisms are applied, which output the values for certain parameters in order to augment the benefit of all the three participants. With the application of this model better organisational results both economic and of service level are achieved. (Author)

  17. Tantalum-Based Ceramics for Refractory Composites

    Science.gov (United States)

    Stewart, David A.; Leiser, Daniel; DiFiore, Robert; Kalvala, Victor

    2006-01-01

    A family of tantalum-based ceramics has been invented as ingredients of high-temperature composite insulating tiles. These materials are suitable for coating and/or permeating the outer layers of rigid porous (foam-like or fibrous) ceramic substrates to (1) render the resulting composite ceramic tiles impervious to hot gases and (2) enable the tiles to survive high heat fluxes at temperatures that can exceed 3,000 F ( 1,600 C).

  18. Design of LTCC-based Ceramic Structure for Chemical Microreactor

    OpenAIRE

    D. Belavic; Hrovat, M.; G. Dolanc; Santo Zarnik, M.; Holc, J.; Makarovic, K.

    2012-01-01

    The design of ceramic chemical microreactor for the production of hydrogen needed in portable polymer-electrolyte membrane (PEM) fuel cells is presented. The microreactor was developed for the steam reforming of liquid fuels with water into hydrogen. The complex three-dimensional ceramic structure of the microreactor includes evaporator(s), mixer(s), reformer and combustor. Low-temperature co-fired ceramic (LTCC) technology was used to fabricate the ceramic structures with buried cavities and...

  19. Development of a ceramic membrane from a lithian spinel, Li1+xMyMn2-yO4 (M=trivalent or tetravalent cations) for a Li ion-selective electrode

    Science.gov (United States)

    Yoon, H.; Venugopal, N.; Rim, T.; Yang, B.; Chung, K.; Ko, T.

    2010-12-01

    Recently a few lithium containing ceramics are reported as promising cathodes for application in lithium batteries. Among them, a spinel-type lithium manganate (LM) exhibits an exceptionally high ion selectivity at room temperature. Thus, LM could have a great potential as an ion selective membrane material for screening interfering ions from lithium ion for the determination of lithium ion in salt solution. In this study, we developed an ion-selective electrode based on LM as a membrane material and investigated its lithium ion selectivity by varying the content of M in composition. A sol-gel process was successfully applied for preparing LM films without resorting to calcination at a high temperature. The LM thin film-type membranes exhibit a high selectivity for Li ion over other cations, a wide operation detection range of 10-5 ~ 10-2 M, and a fast response time less than 60 s. Furthermore, our result demonstrates a linear potentiometric response over a wide range of lithium concentration, which is compared to that of a lithium ion-selective electrode based on an ionophore. Acknowledgements: This research was supported by a grant from the Development of Technology for Extraction of Resources Dissolved in Sea Water Program funded by Ministry of Land Transport and Maritime Affairs in Korean Government (2010).

  20. Advanced Hydrogen Transport Membrane for Coal Gasification

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, Joseph [Praxair, Inc., Tonawanda, NY (United States); Porter, Jason [Colorado School of Mines, Golden, CO (United States); Patki, Neil [Colorado School of Mines, Golden, CO (United States); Kelley, Madison [Colorado School of Mines, Golden, CO (United States); Stanislowski, Josh [Univ. of North Dakota, Grand Forks, ND (United States); Tolbert, Scott [Univ. of North Dakota, Grand Forks, ND (United States); Way, J. Douglas [Colorado School of Mines, Golden, CO (United States); Makuch, David [Praxair, Inc., Tonawanda, NY (United States)

    2015-12-23

    A pilot-scale hydrogen transport membrane (HTM) separator was built that incorporated 98 membranes that were each 24 inches long. This separator used an advanced design to minimize the impact of concentration polarization and separated over 1000 scfh of hydrogen from a hydrogen-nitrogen feed of 5000 scfh that contained 30% hydrogen. This mixture was chosen because it was representative of the hydrogen concentration expected in coal gasification. When tested with an operating gasifier, the hydrogen concentration was lower and contaminants in the syngas adversely impacted membrane performance. All 98 membranes survived the test, but flux was lower than expected. Improved ceramic substrates were produced that have small surface pores to enable membrane production and large pores in the bulk of the substrate to allow high flux. Pd-Au was chosen as the membrane alloy because of its resistance to sulfur contamination and good flux. Processes were developed to produce a large quantity of long membranes for use in the demonstration test.

  1. A high stability Ni-La0.5Ce0.5O2-δ asymmetrical metal-ceramic membrane for hydrogen separation and generation

    Science.gov (United States)

    Zhu, Zhiwen; Sun, Wenping; Wang, Zhongtao; Cao, Jiafeng; Dong, Yingchao; Liu, Wei

    2015-05-01

    In this work, hydrogen permeation properties of Ni-La0.5Ce0.5O2-δ (LDC) asymmetrical cermet membrane are investigated, including hydrogen fluxes (JH2) under different hydrogen partial pressures, the influence of water vapor on JH2 and the long-term stability of the membrane operating under the containing-CO2 atmosphere. Ni-LDC asymmetrical membrane shows the best hydrogen permeability among LDC-based hydrogen separation membranes, inferior to Ni-BaZr0.1Ce0.7Y0.2O3-δ asymmetrical membrane. The water vapor in feed gas is beneficial to hydrogen transport process, which promote an increase of JH2 from 5.64 × 10-8 to 6.83 × 10-8 mol cm-2 s-1 at 900 °C. Stability testing of hydrogen permeation suggests that Ni-LDC membrane remains stable against CO2. A dual function of combining hydrogen separation and generation can be realized by humidifying the sweep gas and enhance the hydrogen output by 1.0-1.5 times. Ni-LDC membrane exhibits desirable performance and durability in dual-function mode. Morphologies and phase structures of the membrane after tests are also characterized by SEM and XRD.

  2. Engineering ceramics

    CERN Document Server

    Bengisu, Murat

    2001-01-01

    This is a comprehensive book applying especially to junior and senior engineering students pursuing Materials Science/ Engineering, Ceramic Engineering and Mechanical Engineering degrees. It is also a reference book for other disciplines such as Chemical Engineering, Biomedical Engineering, Nuclear Engineering and Environmental Engineering. Important properties of most engineering ceramics are given in detailed tables. Many current and possible applications of engineering ceramics are described, which can be used as a guide for materials selection and for potential future research. While covering all relevant information regarding raw materials, processing properties, characterization and applications of engineering ceramics, the book also summarizes most recent innovations and developments in this field as a result of extensive literature search.

  3. Ceramic glossary

    International Nuclear Information System (INIS)

    This book is a 2nd edition that contains new terms reflecting advances in high technology applications of ceramic materials. Definitions for terms which materials scientists, engineers, and technicians need to know are included

  4. Study on skim milk ultrafiltration with a reciprocating rotating tubular ceramic membrane module%往复旋转管式陶瓷膜超滤脱脂奶水溶液的研究

    Institute of Scientific and Technical Information of China (English)

    张晓娜; 梁志辉; 曾燕艳; 范洪波; 吕斯濠

    2013-01-01

    The reciprocating rotary tubular ceramic membrane filtration system could create high shear rate at the membrane surface repeatedly by rotating membrane module in a reciprocating motion to reduce membrane fouling. Compared with the unidirectional rotating filtration and dead-end filtration under the same conditions,the reciprocating rotary filtration system showed superiority in reducing membrane fouling. This research designed ultrafiltration skim milk solution tests to investigate the influence of operating parameters. The results revealed that feed concentration increase could lead to the decrease of membrane permeate flux,and membrane flux could be reduced once the TMP was too high. The increase of rotating speed could induce the increase of shear enhancement and the membrane permeate flux. As the reciprocating rotating cycle increased,the quasi steady membrane permeate flux firstly increases before it decreased. When the feed fluid velocity was at the membrane module velocity,the membrane module being rotated in opposite direction instantaneously generated the largest shear rate on the membrane surface and gained the largest permeate flux. The specific energy consumption per m3 permeate of the reciprocating rotary filtration system was lower than the unidirectional rotating filtration.%往复旋转管式陶瓷膜过滤系统通过膜组件往复旋转在膜表面反复产生高剪切率,达到减缓膜污染的效果。在相同操作条件下,与单向旋转过滤和死端过滤相比较,往复旋转过滤具有更好的减缓膜污染的作用。本实验利用往复旋转膜过滤装置超滤脱脂奶水溶液,考察了各种参数对该膜系统过滤特性的影响。实验结果表明,料液浓度增大,膜通量减小;过高的操作压差将会抑制膜通量增加;旋转速度增大,膜表面剪切强化作用增强,膜通量相应增大;膜稳态通量随往复旋转周期增大呈现先增大后减小的趋势。当料液速

  5. 陶瓷膜超滤技术浓缩乳清的工艺参数研究%Research of processing parameters of whey protein concentrate by inorganic ceramic membrane ultrafiltration

    Institute of Scientific and Technical Information of China (English)

    高红艳; 刘振民; 莫蓓红

    2012-01-01

    The whey protein concentrate was ultrafiltrated by the inorganic ceramic membrane tubes whose aperture was 20nm to concentrate the by-product cheese whey. The optimal condition of pressure of membrane, temperature of material, and pH were studied.The results showed that the pressure of membrane at 0.25MPa, temperature of material at 51℃, and pH at 6.1, the flux of membrane was 169.37L/m2 · h under the optimal conditions.In addition,the whey protein could be concentrated to 5.4% in whey concentrate liquid, and the whey protein concentrate could reach 38.2% by spray drying.%采用孔径为20nm的无机陶瓷膜超滤干酪副产物乳清,浓缩乳清蛋白。通过对膜过滤压力、温度以及乳清pH三个因素进行单因素分析以及正交实验优化,得到最佳工艺条件:操作压力0.25MPa,温度51℃,pH6.1,此条件下超滤膜渗透通量达到169.37I/m2·h,乳清蛋白可浓缩至5.4%,经喷雾干燥制得WPC蛋白质含量为38.2%。

  6. Tailored ceramics

    International Nuclear Information System (INIS)

    In polyphase tailored ceramic forms two distinct modes of radionuclide immobilization occur. At high waste loadings the radionuclides are distributed through most of the ceramic phases in dilute solid solution, as indicated schematically in this paper. However, in the case of low waste loadings, or a high loading of a waste with low radionuclide content, the ceramic can be designed with only selected phases containing the radionuclides. The remaining material forms nonradioactive phases which provide a degree of physical microstructural isolation. The research and development work with polyphase ceramic nuclear waste forms over the past ten years is discussed. It has demonstrated the critical attributes which suggest them as a waste form for future HLW disposal. From a safety standpoint, the crystalline phases in the ceramic waste forms offer the potential for demonstrable chemical durability in immobilizing the long-lived radionuclides in a geologic environment. With continued experimental research on pure phases, analysis of mineral analogue behavior in geochemical environments, and the study of radiation effects, realistic predictive models for waste form behavior over geologic time scales are feasible. The ceramic forms extend the degree of freedom for the economic optimization of the waste disposal system

  7. Structural stability and oxygen permeability of BaCo1−xNbxO3−δ ceramic membranes for air separation

    International Nuclear Information System (INIS)

    Highlights: • BCNx membranes with high oxygen permeation flux were prepared. • Oxygen permeability of BCNx membranes is stable at 900 °C. • Phase transition is governed by oxygen partial pressure and temperature. • Degradation mechanism of BCNx membrane is suggested. - Abstract: BaCo1−xNbxO3−δ (BCNx, x = 0.1–0.2) membranes were synthesized through conventional solid-phase reactions. The introduction of niobium facilitates the formation of the cubic perovskite structure and decreases oxygen nonstoichiometry. BCNx membranes possess higher oxygen permeation flux compared with BaCo0.7Fe0.2Nb0.1O3−δ membrane at the same condition. A stable permeation flux as high as 2.61 ml cm−2 min−1 is obtained through BaCo0.9Nb0.1O3−δ membrane at 900 °C under the Air/He gradient. Long-time permeation study shows that the oxygen fluxes of BCNx membranes are stable at 900 °C but degrade slowly with time at 850 °C. XRD and TG–DSC results indicate that the degradation behavior occured at 850 °C is due to the phase transition from the cubic perovskite to monoclinic or orthorhombic structure, which is governed by the oxygen partial pressure and temperature. The oxidation of cobalt ion is considered to be the nature for the phase transition, which makes the tolerance factor increasing and results in structural destabilization

  8. FY2015 ceramic fuels development annual highlights

    Energy Technology Data Exchange (ETDEWEB)

    Mcclellan, Kenneth James [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

    2015-09-22

    Key challenges for the Advanced Fuels Campaign are the development of fuel technologies to enable major increases in fuel performance (safety, reliability, power and burnup) beyond current technologies, and development of characterization methods and predictive fuel performance models to enable more efficient development and licensing of advanced fuels. Ceramic fuel development activities for fiscal year 2015 fell within the areas of 1) National and International Technical Integration, 2) Advanced Accident Tolerant Ceramic Fuel Development, 3) Advanced Techniques and Reference Materials Development, and 4) Fabrication of Enriched Ceramic Fuels. High uranium density fuels were the focus of the ceramic fuels efforts. Accomplishments for FY15 primarily reflect the prioritization of identification and assessment of new ceramic fuels for light water reactors which have enhanced accident tolerance while also maintaining or improving normal operation performance, and exploration of advanced post irradiation examination techniques which will support more efficient testing and qualification of new fuel systems.

  9. Development of nickel membranes deposited on ceramic materials by electroless plating: studies of the hydrogen perm-selectivity properties at elevated temperatures

    International Nuclear Information System (INIS)

    The main objective of this work was to synthesize nickel based membranes by electroless plating on materials such as alumina-α, alumina-γ and zirconia with various textures and to determine their hydrogen perm-selectivity at high temperatures. The synthesis of metal films of high purity (≥ 99% mass Ni) resulting from the choice of hydrazine with its dual role of reducing and complexing agent has revealed that the diameter of pores on the surface support has an impact on the quality of metal adherence. The various contributions of hydrogen transport through these composite membranes at low temperatures (Knudsen and surface diffusion) and at high temperatures (Knudsen and activated diffusion) was established. At its implementation in a membrane reactor (reaction of propane dehydrogenation), the layer of nickel showed a very good resistance to coking. (author)

  10. Evaluation and characterization of ceramic membranes based on Pdms/SiC containing phosphotungstic acid as electrolytes for PEM-FC

    International Nuclear Information System (INIS)

    This work presents the development of membranes with potential use in Proton Exchange Fuel Cells (PEM-FC), consisting of hybrid materials based on poly(dimethylsiloxane), crosslinked with tetraethyl orthosilicate (TEOS), and reinforced with silicon carbide and phosphotungstic acid. The membrane series PDMS/TEOS/SiC/PWA were prepared by the reaction of PDMS and TEOS, 70/30% proportions in mass, catalyzed by dibutyltin dilaurate. SiC was incorporated in a 25% proportion, and PWA in varied proportions (5, 10, 15 and 20%), by weight. The membranes were characterized by Thermo-Gravimetric Analysis (TGA), X-ray Diffraction, Scanning Electron Microscopy and impedance spectroscopy. SiC and PWA addition to the membrane increased both structure organization and material crystallinity. The insertion of PWA provided an increase in the conductivity. However, maximum conductivity was obtained with concentration levels above 10%. The insertion of SiC associated with the PWA did not influence the conductivity for concentrations between 10 and 20%. (author)

  11. Auto-Thermal Reforming Using Mixed Ion-Electronic Conducting Ceramic Membranes for a Small-Scale H2 Production Plant

    Directory of Open Access Journals (Sweden)

    Vincenzo Spallina

    2015-03-01

    Full Text Available The integration of mixed ionic electronic conducting (MIEC membranes for air separation in a small-to-medium scale unit for H2 production (in the range of 650–850 Nm3/h via auto-thermal reforming of methane has been investigated in the present study. Membranes based on mixed ionic electronic conducting oxides such as Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF give sufficiently high oxygen fluxes at temperatures above 800 °C with high purity (higher than 99%. Experimental results of membrane permeation tests are presented and used for the reactor design with a detailed reactor model. The assessment of the H2 plant has been carried out for different operating conditions and reactor geometry and an energy analysis has been carried out with the flowsheeting software Aspen Plus, including also the turbomachines required for a proper thermal integration. A micro-gas turbine is integrated in the system in order to supply part of the electricity required in the system. The analysis of the system shows that the reforming efficiency is in the range of 62%–70% in the case where the temperature at the auto-thermal reforming membrane reactor (ATR-MR is equal to 900 °C. When the electric consumption and the thermal export are included the efficiency of the plant approaches 74%–78%. The design of the reactor has been carried out using a reactor model linked to the Aspen flowsheet and the results show that with a larger reactor volume the performance of the system can be improved, especially because of the reduced electric consumption. From this analysis it has been found that for a production of about 790 Nm3/h pure H2, a reactor with a diameter of 1 m and length of 1.8 m with about 1500 membranes of 2 cm diameter is required.

  12. On the use of supported ceria membranes for oxyfuel process/syngas production

    DEFF Research Database (Denmark)

    Lobera, M.P.; Serra, J.M.; Foghmoes, Søren Preben Vagn;

    2011-01-01

    Ceramic oxygen transport membranes (OTMs) enable selective oxygen separation from air at high temperatures. Among several potential applications for OTMs, the use in (1) oxygen production for oxyfuel power plants and (2) the integration in high-temperature catalytic membrane reactors for alkane...... upgrading through selective oxidative reactions are of special interest. Nevertheless, these applications involve the direct contact of the membrane surface with carbon-rich atmospheres. Most state-of-the-art permeable membranes are based on perovskites, which are prone to carbonation under operation in CO2...... with an oxygen reduction catalyst. Oxygen separation was studied using air as feed and argon/CO2 or argon/CH4 mixtures as sweep gas in the temperature range 750–1000 °C. The supported membrane exhibited a maximum oxygen flux of ca. 5 ml min−1 cm−2 at 1000 °C when diluted methane was used as sweep gas...

  13. ADVANCED HYDROGEN TRANSPORT MEMBRANES FOR VISION 21 FOSSIL FUEL PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Shane E. Roark; Anthony F. Sammells; Richard Mackay; Scott R. Morrison; Sara L. Rolfe; U. Balachandran; Richard N. Kleiner; James E. Stephen; Frank E. Anderson; Shandra Ratnasamy; Jon P. Wagner; Clive Brereton

    2004-01-30

    The objective of this project is to develop an environmentally benign, inexpensive, and efficient method for separating hydrogen from gas mixtures produced during industrial processes, such as coal gasification. Currently, this project is focusing on four basic categories of dense membranes: (1) mixed conducting ceramic/ceramic composites, (2) mixed conducting ceramic/metal (cermet) composites, (3) cermets with hydrogen permeable metals, and (4) layered composites with hydrogen permeable alloys. The primary technical challenge in achieving the goals of this project will be to optimize membrane composition to enable practical hydrogen separation rates and chemical stability. Other key aspects of this developing technology include catalysis, ceramic processing methods, and separation unit design operating under high pressure. To achieve these technical goals, Eltron Research Inc. has organized a consortium consisting of CoorsTek, Sued Chemie, Inc. (SCI), Argonne National Laboratory (ANL), and NORAM. Hydrogen permeation rates in excess of 50 mL {center_dot} min{sup -1} {center_dot} cm{sup 2} at {approx}440 C were routinely achieved under less than optimal experimental conditions using a range of membrane compositions. Factors that limit the maximum permeation attainable were determined to be mass transport resistance of H{sub 2} to and from the membrane surface, as well as surface contamination. Mass transport resistance was partially overcome by increasing the feed and sweep gas flow rates to greater than five liters per minute. Under these experimental conditions, H2 permeation rates in excess of 350 mL {center_dot} min{sup -1} {center_dot} cm{sup 2} at {approx}440 C were attained. These results are presented in this report, in addition to progress with cermets, thin film fabrication, catalyst development, and H{sub 2} separation unit scale up.

  14. Hydrogen Permeation Performance of Ni-BaZr0.1Ce0.7Y0.2O3-δ Metal-Ceramic Hollow Fiber Membrane

    Science.gov (United States)

    Yang, Chun-li; Xu, Qi-ming; Zhu, Zhi-wen; Liu, Wei

    2012-04-01

    A dense Ni-BaZr0.1Ce0.7Y0.2O3-δ (BZCY) cermet hollow fiber is fabricated by sintering NiO-BZCY hollow fiber precursors prepared by phase inversion method in 5%H2/95%Ar and its hydrogen permeation performance is investigated. The Ni-BZCY hollow fiber membrane possesses a “sandwich" structure. Finger-like structures are observed near both the inner and outer surfaces, while a dense layer is present in the center part. With 200 mL/min wet 20%H2/80%N2 on the shell side and 150 mL/min high purity Ar on the core side, the hydrogen permeation flux through the Ni-BZCY hollow fiber membrane at 900 °C is 0.53 μmol/cm2s. Owing to a high packing density, the hydrogen permeation flux per unit volume is greatly improved and membrane components composed of an assembly of hollow fibers may be applied in industrial hydrogen separation.

  15. Hydrogen Permeation Performance of Ni-BaZr0.1Ce0.7Y0.2O3-δ Metal-Ceramic Hollow Fiber Membrane

    Institute of Scientific and Technical Information of China (English)

    Chun-li Yang; Qi-ming Xu; Zhi-wen Zhu; Wei Liu

    2012-01-01

    A dense Ni-BaZr0.1Ce0.7Y0.2O3-δ (BZCY) cermet hollow fiber is fabricated by sintering NiOBZCY hollow fiber precursors prepared by phase inversion method in 5%H2/95%Ar and its hydrogen permeation performance is investigated. The Ni-BZCY hollow fiber membrane possesses a "sandwich" structure.Finger-like structures are observed near both the inner and outer surfaces,while a dense layer is present in the center part.With 200 mL/min wet 20%H2/80%N2 on the shell side and 150 mL/min high purity Ar on the core side,the hydrogen permeation flux through the Ni-BZCY hollow fiber membrane at 900 ℃ is 0.53 μmol/cm2s.Owing to a high packing density,the hydrogen permeation flux per unit volume is greatly improved and membrane components composed of an assembly of hollow fibers may be applied in industrial hydrogen separation.

  16. Synthesis of ceramics membranes using ZrO{sub 2} obtained by Pechini method aiming it application in oil/water separation; Sintese de membranas ceramicas utilizando ZrO{sub 2} obtido pelo metodo Pechini visando sua aplicacao na separacao oleo/agua

    Energy Technology Data Exchange (ETDEWEB)

    Maia, D.F.; Lira, H.L.; Vilar, M.A.; Costa, A.C.F.M.; Oliveira, J.B.L.; Kiminami, R.H.G.A.; Gama, L.

    2004-07-01

    The water produced in the oil production presents emulsified oil drops of difficult separation causing problems in the reinjection and the discarding. The conventional methods used in the separation oil/water don't clean all the water with efficiency and low cost. Thus, the ceramic membranes appear as a new option for being material very resistant chemistry and thermal, of high perm selective and high efficiency in use in processes of micro filtration and ultrafiltration separation. The zirconia is considered an adequate material to obtain of such membranes and the Pechini method is one promising technique in the attainment of after ultrafine with controlled characteristics. Thus the objective of this work was to prepare ceramic membranes from after synthesized by the Pechini method. The results had shown that the Pechini method was efficient in the attainment of ZrO{sub 2} powder, nanometric, with size of crystal of 7,2 nm and with average diameter of agglomerated 4,94{mu}, indicating that this material can be used in the attainment of membranes of micro filtration and ultrafiltration, adjusted to the separation oil/water The micrographs of the obtained membranes show a homogeneous surface where if it can visualize pores uniformly distributed. (author)

  17. Palladium coated porous anodic alumina membranes for gas reforming processes

    Science.gov (United States)

    Wu, Jeremy P.; Brown, Ian W. M.; Bowden, Mark E.; Kemmitt, Timothy

    2010-11-01

    Nanostructured ceramic membranes with ultrathin coatings of palladium metal have been demonstrated to separate hydrogen gas from a gas mixture containing nitrogen with 10% carbon dioxide and 10% hydrogen at temperatures up to 550 °C. The mechanically robust and thermally durable membranes were fabricated using a combination of conventional and high-efficiency anodisation processes on high purity aluminium foils. A pH-neutral plating solution has also been developed to enable electroless deposition of palladium metal on templates which were normally prone to chemical corrosion in strong acid or base environment. Activation and thus seeding of palladium nuclei on the surface of the template were essential to ensure uniform and fast deposition, and the thickness of the metal film was controlled by time of deposition. The palladium coated membranes showed improved hydrogen selectivity with increased temperature as well as after prolonged exposure to hydrogen, demonstrating excellent potential for gas separation technologies.

  18. Nano-ceramics and method thereof

    Science.gov (United States)

    Satcher, Jr., Joe H.; Gash, Alex; Simpson, Randall; Landingham, Richard; Reibold, Robert A.

    2006-08-08

    Disclosed herein is a method to produce ceramic materials utilizing the sol-gel process. The methods enable the preparation of intimate homogeneous dispersions of materials while offering the ability to control the size of one component within another. The method also enables the preparation of materials that will densify at reduced temperature.

  19. Ceramic microfabrication by rapid prototyping process chains

    Indian Academy of Sciences (India)

    R Knitter; W Bauer

    2003-02-01

    Fabrication of micropatterned ceramics or ceramic microparts make high demands on the precision and resolution of the moulding process. As finishing of miniaturised or micropatterned ceramic components is nearly impossible, shaping has to be done by a replication step in the green, unfired state. To avoid high tooling costs in product development, a rapid prototyping process chain has been established that enables rapid manufacturing of ceramic microcomponents from functional models to small lot series within a short time. This process chain combines the fast and inexpensive supply of master models by rapid prototyping with accurate and flexible ceramic manufacturing by low-pressure injection moulding. Besides proper feedstock preparation and sufficient small grain size, the quality of the final components is mainly influenced by the quality of the master model. Hence, the rapid prototyping method must be carefully selected to meet the requirements of the component to be fabricated.

  20. Industrial ceramics

    International Nuclear Information System (INIS)

    After having given the definition of the term 'ceramics', the author describes the different manufacturing processes of these compounds. These materials are particularly used in the fields of 1)petroleum industry (in primary and secondary reforming units, in carbon black reactors and ethylene furnaces). 2)nuclear industry (for instance UO2 and PuO2 as fuels; SiC for encapsulation; boron carbides for control systems..)

  1. Bubble-free ozone addition through ceramic membranes for wet-oxidative waste water treatment; Blasenfreier Ozoneintrag durch keramische Membranen zur nassoxidativen Abwasserbehandlung

    Energy Technology Data Exchange (ETDEWEB)

    Janknecht, P.; Wilderer, P.A. [Technische Univ. Muenchen, Garching (Germany). Lehrstuhl und Pruefamt fuer Wasserguete- und Abfallwirtschaft

    1999-07-01

    A prerequisite for successful wet oxidation is very accurately tuned and carefully monitored process control. In the alternative, a decline in water quality is actually possible. In particular, earlier studies in the ozonification of landfill leachate encountered problems in reducing levels of AOX in the presence of halogenated hydrocarbons. Serious problems in process control may arise when ozone is conventionally added and forms bubbles in the presence of surface-active substances; this foam accumulates and is so persistent as to evade mechanical control. Since the formation of foam is directly due to gas bubbles carried in, bubble-free addition of ozone through a membrane may be a viable approach. (orig.) [German] Voraussetzung fuer den Erfolg einer Nassoxidation ist eine sehr genau eingestellte und sorgfaeltig ueberwachte Prozessfuehrung, da anderenfalls auch eine Verschlechterung der Wasserqualitaet eintreten kann; insbesondere haben sich hier bei frueheren Untersuchungen zur Ozonung von Deponiesickerwaessern Schwierigkeiten bei der Reduzierung des AOX-Wertes in Anwesenheit von halogenierten Kohlenwasserstoffen ergeben. Gravierende Schwierigkeiten in der Prozessfuehrung kann Schaum bereiten, der sich bei konventionellem Blaseneintrag des Ozons in Anwesenheit von oberflaechenaktiven Substanzen bildet, sich in der Anlage ansammelt und dabei so bestaendig ist, dass er auf mechanische Weise nicht zu kontrollieren ist. Da die Schaumbildung direkt auf die eingetragenen Gasblasen zurueckzufuehren ist, stellt der blasenfreie Eintrag von Ozon durch eine Membran einen moeglichen Loesungsansatz dar. (orig.)

  2. Review. Freeze-casting: Fabrication of highly porous and hierarchical ceramic supports for energy applications

    Energy Technology Data Exchange (ETDEWEB)

    Gaudillere, C.; Serra, J. M.

    2016-05-01

    The manufacture of structured ceramic porous support knows an important boom since more than a decade with the development of new shaping techniques. Among the most promising ones, the freeze-casting also called Ice-Tem plating allows the fabrication of ceramic parts exhibiting high porosity (>50%) and vertically aligned and hierarchically organized pores. Such structures were firstly conceived for biomedical applications like bone substitute and tissue engineering, but the distinctive features of freeze-cast structures have attracted the attention of diverse scientific fields, especially in high temperature ceramic-based energy production systems. Indeed, technologies like (a) Solid Oxide Fuel Cell (SOFC) and Electrolyser Cell (SOEC), (b) gas separation (O{sub 2}, H{sub 2}) by asymmetric supported membranes based on mixed ionic and electronic conductors (MIEC) or hydrogen-permeable metals, and (c) Catalytic Membrane Reactor (CMR) systems present a porous component in their physical structure. This latest, presenting a tortuous pathway for gas access and as a consequence, a high transport limitation, is known to be a limiting component for the operation at high flow streams that would enable to reach industrial target. (Author)

  3. Review. Freeze-casting: Fabrication of highly porous and hierarchical ceramic supports for energy applications

    International Nuclear Information System (INIS)

    The manufacture of structured ceramic porous support knows an important boom since more than a decade with the development of new shaping techniques. Among the most promising ones, the freeze-casting also called Ice-Tem plating allows the fabrication of ceramic parts exhibiting high porosity (>50%) and vertically aligned and hierarchically organized pores. Such structures were firstly conceived for biomedical applications like bone substitute and tissue engineering, but the distinctive features of freeze-cast structures have attracted the attention of diverse scientific fields, especially in high temperature ceramic-based energy production systems. Indeed, technologies like (a) Solid Oxide Fuel Cell (SOFC) and Electrolyser Cell (SOEC), (b) gas separation (O2, H2) by asymmetric supported membranes based on mixed ionic and electronic conductors (MIEC) or hydrogen-permeable metals, and (c) Catalytic Membrane Reactor (CMR) systems present a porous component in their physical structure. This latest, presenting a tortuous pathway for gas access and as a consequence, a high transport limitation, is known to be a limiting component for the operation at high flow streams that would enable to reach industrial target. (Author)

  4. Treatment of Marble Processing Wastewaters by Ceramic Micro-Filtration Membrane%陶瓷微滤膜处理大理石加工废水的研究

    Institute of Scientific and Technical Information of China (English)

    金珊; 孙杰

    2011-01-01

    采用孔径为0.8μm的陶瓷膜处理大理石生产过程中产生的废水,研究了操作压差和膜面流速等对膜性能的影响,结果表明,合适的操作条件是操作压差0.07 MPa,膜面流速1.0 m/s,滤出液中固体颗粒的截留率在99.2%~99.8%,膜微滤过程对废水的pH值和COD值的影响不大,运行中膜通量稳定平均值为400L/(m2·h),料液的固体质量浓度大于55 g/L时,膜通量明显下降.对污染膜用清水清洗20 min和体积分数为1%的HNO3溶液清洗30 min,膜通量可以得到完全恢复.渗透液返回生产工序循环使用,截留液进入沉降池.%Treatment of marble processing wastewaters by ceramic micro-filtration membrane with pore size of 0.8 μm was performed.The effects of the transmembrane pressure and crossflow velocity on the MF performance were investigated.The experimental results show that the feasible transmembrane pressure is 0.07 MPa and crossflow velocity 1.0 m/s.The solid rejections of the permeate samples were from 99.2% to 99.8%.The MF process has no remarkable effect on the wastewater pH and COD, the membrane flux remained constant throughout the experiment, the average value is 400 L/(m2 · h).The flux was remarkable decline when the solid concentration of feed liquid is over 55 g/L.The membrane flux can be recovered completely after cleaned by the water with 20 minutes and nitric acid solution (volume fraction 1 %)with 30 minutes.The MF process allowed the treated water to be recycled into the process, whereas the concentrated stream (rich in particulate matter) turned into sedimentation pool.

  5. Development of Advanced Ceramic Manufacturing Technology; FINAL

    International Nuclear Information System (INIS)

    Advanced structural ceramics are enabling materials for new transportation engine systems that have the potential for significantly reducing energy consumption and pollution in automobiles and heavy vehicles. Ceramic component reliability and performance have been demonstrated in previous U.S. DOE initiatives, but high manufacturing cost was recognized as a major barrier to commercialization. Norton Advanced Ceramics (NAC), a division of Saint-Gobain Industrial Ceramics, Inc. (SGIC), was selected to perform a major Advanced Ceramics Manufacturing Technology (ACMT) Program. The overall objectives of NAC's program were to design, develop, and demonstrate advanced manufacturing technology for the production of ceramic exhaust valves for diesel engines. The specific objectives were (1) to reduce the manufacturing cost by an order of magnitude, (2) to develop and demonstrate process capability and reproducibility, and (3) to validate ceramic valve performance, durability, and reliability. I n order to achieve these objectives, NAC, a leading U.S. advanced ceramics component manufacturer, assembled a multidisciplinary, vertically integrated team. This team included: a major diesel engine builder, Detroit Diesel Corporation (DDC); a corporate ceramics research division, SGIC's Northboro R and D Center; intelligent processing system developers, BDM Federal/MATSYS; a furnace equipment company, Centorr/Vacuum Industries; a sintering expert, Wittmer Consultants; a production OEM, Deco-Grand; a wheel manufacturer and grinding operation developer, Norton Company's Higgins Grinding Technology Center (HGTC); a ceramic machine shop, Chand Kare Technical Ceramics; and a manufacturing cost consultant, IBIS Associates. The program was divided into four major tasks: Component Design and Specification, Component Manufacturing Technology Development, Inspection and Testing, and Process Demonstration

  6. Synthesis and characterization of ceramic-supported and metal-supported membrane layers for the separation of CO{sub 2} in fossil-fuel power plants; Herstellung und Charakterisierung von keramik- und metallgestuetzten Membranschichten fuer die CO{sub 2}-Abtrennung in fossilen Kraftwerken

    Energy Technology Data Exchange (ETDEWEB)

    Hauler, Felix

    2010-07-01

    The separation of CO{sub 2} in fossil fuel power plants has become a very important issue due to the contribution of this greenhouse gas to global warming. Thin microporous membranes are promising candidates for separating CO{sub 2} from gas flow before being exhausted into the atmosphere. The membrane demands are good permeation and separation properties and high stability under operation conditions. Novel sol-gel derived materials composed of TiO{sub 2}/ZrO{sub 2} and stabilized SiO{sub 2} seem to be promising due to their good chemical stability and microporous character, especially for the separation of H{sub 2} and CO{sub 2}. Metallic substrates should be preferred as membrane support because they exhibit practical advantages combining good mechanical stability and the benefit of facilitated joining. The present thesis deals with the development of sol-gel derived microporous membrane layers on ceramic and metallic supports for the separation of CO{sub 2}. In this context, the optimized preparation of high-quality membranes with TiO{sub 2}/ZrO{sub 2} and Ni, Co, Zr, Ti doped SiO{sub 2} top layers is presented. These multilayered membranes consist of a graded pore structure to provide a smooth transition of the pore size from the support to the functional layer. Due to the good surface properties, the ceramic substrates only need one interlayer, whereas the rough metallic substrates exhibiting larger pores require a total of three interlayers to obtain an enhanced surface quality. On both types of supports, crack-free functional layers with a thickness below 100 nm were deposited by dip-coating. The unsupported and supported sol-gel materials used for the top layers were investigated in terms of structural properties by thermal analysis, sorption measurements, X-ray diffraction and electron microscopy. Gas permeation tests with He, H{sub 2}, CO{sub 2} und N{sub 2} were carried out to determine the membrane performance with regard to permeation rates and

  7. 重组毕赤酵母产华根霉脂肪酶的陶瓷膜微滤除菌工艺研究%Pilot scale ceramic membrane microfiltration for Pichia pastoris cells separation in production of Rhizopus chinensis lipase

    Institute of Scientific and Technical Information of China (English)

    谢甲有; 喻晓蔚; 徐岩

    2012-01-01

    在重组毕赤酵母生产脂肪酶的提取中,应用并优化了陶瓷膜微滤除菌工艺,确定了最佳条件为膜截留分子量500 kDa、膜操作压力0.3 MPa、温度20℃、湿菌体含量35%,先对发酵液稀释1.5倍后再进行洗滤.40L处理量的小试结果显示,在5h处理时间内,能获得高达92.70%的酶活回收率.560 L处理量的中试放大,酶活回收率为89.91%,耗时5.5h.在膜的清洗与再生中,采用2% NaClO和2%NaOH在60℃、0.3 MPa膜压力下进行清洗40 min,清水膜通量恢复率为98.14%.陶瓷膜与板框除菌的比较试验发现,两种方法都获得了微生物限量合格的产品和较高的酶活回收率,但陶瓷膜微滤的滤液微生物检出量更低,处理时间较短,动力能耗更低,易与超滤膜耦合提取,废水产生量更少,菌体废渣易于回收,是一种节能减排、清洁环保的新型除菌工艺.%In this research, ceramic rrEmbrane microfiltration was applied to separate Pichia pastoris cells in the process of production of Rhizopus chinensis lipase. The optimal conditions were 500 kDb MWCO with trans-membrane pressure of 0.3 MPa, ternpreture of 20 ℃ , wet cell content of 35% (w/v) and 1.5 times dilution of the fermentation broth before rricrcfiltration sterilization with ceramic membrane. In the 40 L broth microfiltrating treatment, the results showed that the lipase activity recovery of 92.70% was obtained after 5 h operation. Scaling up to 560 L, the lipase activity recovery of 89.91% was obtained after 5.5 h operation. On the industrial production scale, the total membrane area of ceramic membrane microfiltraticn could be increased to 115% -120%, based on the unit membrane area treatment capacity of 17017m2. After rinsing with 2% NaClO and 2% NaOH at 60 ℃ and 0.3 MPa for 40 minutes, the recovery of ceramic membrane could reach 98.14% of the water flux. Gmpared with frame filter, both methods could achieve high lipase activity recovery and qualified products

  8. Monolithic ceramics

    Science.gov (United States)

    Herbell, Thomas P.; Sanders, William A.

    1992-01-01

    A development history and current development status evaluation are presented for SiC and Si3N4 monolithic ceramics. In the absence of widely sought improvements in these materials' toughness, and associated reliability in structural applications, uses will remain restricted to components in noncritical, nonman-rated aerospace applications such as cruise missile and drone gas turbine engine components. In such high temperature engine-section components, projected costs lie below those associated with superalloy-based short-life/expendable engines. Advancements are required in processing technology for the sake of fewer and smaller microstructural flaws.

  9. Ceramic composition

    International Nuclear Information System (INIS)

    Improved ceramic compositions useful for cutting tools and the like are described. They are composed of an essentially homogeneous admixture of sintered powders of an aluminum oxide base material with other refractories including zirconium oxide, titanium oxide, hafnium oxide, titanium nitride, zirconium nitride, and tungsten or molybdenum carbide. In addition to their common and improved properties of hardness and strength, many of these compositions may be made by simple cold-pressing and sintering procedures. This avoids the known drawbacks of conventional hot press production

  10. Luminescent ceramics for LED conversion

    Science.gov (United States)

    Raukas, M.; Wei, G.; Bergenek, K.; Kelso, J.; Zink, N.; Zheng, Y.; Hannah, M.; Stough, M.; Wirth, R.; Linkov, A.; Jermann, F.; Eisert, D.

    2011-03-01

    Many LED-based applications would benefit from more efficient and/or high lumen output devices that enable usage in both white and single color illumination schemes. In the present article we briefly review the materials research history leading to optical ceramic converters and discuss their typical characteristics. Recently demonstrated high performance values in terms of efficacy and external quantum efficiency in orange (amber) spectral region are described.

  11. Study of aqueous pectin solutions microfiltration process by ceramic membrane - doi: 10.4025/actascitechnol.v33i2.7000

    Directory of Open Access Journals (Sweden)

    Vitor Renan da Silva

    2011-04-01

    Full Text Available In this work, pressure effects, separation efficiency and resistive effects of microfiltration of pectin solution were investigated. Stabilized permeate flux values were obtained for solutions concentrations of 1.0 and 2.0 g L-1 under different pressure conditions of 0.4, 0.8, 1.2 and 1.6 bar. A full factorial design with two levels was applied to evaluate the effects of the pressure, temperature and concentration in the process resistances. The experiments were performed in a crossflow microfiltration system with multitubular membrane with nominal pore size of 0.44 µm and feed flow of 1.0 m³ h-1. Pectin retention coefficients and process resistances were obtained following the resistances in series model. It was observed that the highest values of permeate flux for concentration solution of 1.0 and 2.0 g L-1 were at pressure of 1.2 and 0.8 bar, respectively, however, the lowest obtained permeate flux were at 1.6 bar. The permeate flux and the polarization resistance increased, respectively, with increasing temperature and concentration. The results showed that the lowest value of the retention coefficient was 93.4% and the most significant resistance was due to fouling. The highest value of resistance was 4.13 x 109 m² kg-1 at temperature of 30°C and concentration of 2.0 g L-1.

  12. Environmental durability of ceramics and ceramic composites

    Science.gov (United States)

    Fox, Dennis S.

    1992-01-01

    An account is given of the current understanding of the environmental durability of both monolithic ceramics and ceramic-matrix composites, with a view to the prospective development of methods for the characterization, prediction, and improvement of ceramics' environmental durability. Attention is given to the environmental degradation behaviors of SiC, Si3N4, Al2O3, and glass-ceramic matrix compositions. The focus of corrosion prevention in Si-based ceramics such as SiC and Si3N4 is on the high and low sulfur fuel combustion-product effects encountered in heat engine applications of these ceramics; sintering additives and raw material impurities are noted to play a decisive role in ceramics' high temperature environmental response.

  13. Dental ceramics: An update

    OpenAIRE

    Shenoy Arvind; Shenoy Nina

    2010-01-01

    In the last few decades, there have been tremendous advances in the mechanical properties and methods of fabrication of ceramic materials. While porcelain-based materials are still a major component of the market, there have been moves to replace metal ceramics systems with all ceramic systems. Advances in bonding techniques have increased the range and scope for use of ceramics in dentistry. In this brief review, we will discuss advances in ceramic materials and fabrication techniques. Examp...

  14. Thinning of PLZT ceramic wafers for sensor integration

    Science.gov (United States)

    Jin, Na; Liu, Weiguo

    2010-08-01

    Characteristics of transparent PLZT ceramics can be tailored by controlling the component of them, and therefore showed excellent dielectric, piezoelectric, pyroelectric and ferroelectric properties. To integrate the ceramics with microelectronic circuit to realize integrated applications, the ceramic wafers have to be thinned down to micrometer scale in thickness. A7/65/35 PLZT ceramic wafer was selected in this study for the thinning process. Size of the wafer was 10×10mm with an initial thickness of 300μm. A novel membrane transfer process (MTP) was developed for the thinning and integration of the ceramic wafers. In the MTP process, the ceramic wafer was bonded to silicon wafer using a polymer bonding method. Mechanical grinding method was applied to reduce the thickness of the ceramic. To minimize the surface damage in the ceramic wafer caused by the mechanical grinding, magnetorheological finishing (MRF) method was utilized to polish the wafer. White light interference (WLI) apparatus was used to monitor the surface qualities of the grinded and ploished ceramic wafers. For the PLZT membrane obtained from the MTP process, the final thickness of the thinned and polished wafer was 10μm, the surface roughness was below 1nm in rms, and the flatness was better than λ/5.

  15. Crack Growth along Interfaces in Porous Ceramic Layers

    DEFF Research Database (Denmark)

    Sørensen, Bent F.; Horsewell, Andy

    2001-01-01

    Crack growth along porous ceramic layers was studied experimentally. Double cantilever beam sandwich specimens were loaded with pure bending moments to obtain stable crack growth. The experiments were conducted in an environmental scanning electron microscope enabling in situ observations of...

  16. Additive manufacturing of polymer-derived ceramics.

    Science.gov (United States)

    Eckel, Zak C; Zhou, Chaoyin; Martin, John H; Jacobsen, Alan J; Carter, William B; Schaedler, Tobias A

    2016-01-01

    The extremely high melting point of many ceramics adds challenges to additive manufacturing as compared with metals and polymers. Because ceramics cannot be cast or machined easily, three-dimensional (3D) printing enables a big leap in geometrical flexibility. We report preceramic monomers that are cured with ultraviolet light in a stereolithography 3D printer or through a patterned mask, forming 3D polymer structures that can have complex shape and cellular architecture. These polymer structures can be pyrolyzed to a ceramic with uniform shrinkage and virtually no porosity. Silicon oxycarbide microlattice and honeycomb cellular materials fabricated with this approach exhibit higher strength than ceramic foams of similar density. Additive manufacturing of such materials is of interest for propulsion components, thermal protection systems, porous burners, microelectromechanical systems, and electronic device packaging. PMID:26721993

  17. Additive manufacturing of polymer-derived ceramics

    Science.gov (United States)

    Eckel, Zak C.; Zhou, Chaoyin; Martin, John H.; Jacobsen, Alan J.; Carter, William B.; Schaedler, Tobias A.

    2016-01-01

    The extremely high melting point of many ceramics adds challenges to additive manufacturing as compared with metals and polymers. Because ceramics cannot be cast or machined easily, three-dimensional (3D) printing enables a big leap in geometrical flexibility. We report preceramic monomers that are cured with ultraviolet light in a stereolithography 3D printer or through a patterned mask, forming 3D polymer structures that can have complex shape and cellular architecture. These polymer structures can be pyrolyzed to a ceramic with uniform shrinkage and virtually no porosity. Silicon oxycarbide microlattice and honeycomb cellular materials fabricated with this approach exhibit higher strength than ceramic foams of similar density. Additive manufacturing of such materials is of interest for propulsion components, thermal protection systems, porous burners, microelectromechanical systems, and electronic device packaging.

  18. ADVANCED HYDROGEN TRANSPORT MEMBRANES FOR VISION 21 FOSSIL FUEL PLANTS

    International Nuclear Information System (INIS)

    Eltron Research Inc., and team members CoorsTek, McDermott Technology, inc., Sued Chemie, Argonne National Laboratory, and Oak Ridge National Laboratory are developing an environmentally benign, inexpensive, and efficient method for separating hydrogen from gas mixtures produced during industrial processes, such as coal gasification. This project was motivated by the National Energy Technology Laboratory (NETL) Vision 21 initiative which seeks to economically eliminate environmental concerns associated with the use of fossil fuels. This objective is being pursued using dense membranes based in part on Eltron-patented ceramic materials with a demonstrated ability for proton and electron conduction. The technical goals are being addressed by modifying single-phase and composite membrane composition and microstructure to maximize proton and electron conductivity without loss of material stability. Ultimately, these materials must enable hydrogen separation at practical rates under ambient and high-pressure conditions, without deactivation in the presence of feedstream components such as carbon dioxide, water, and sulfur

  19. Dental ceramics: An update

    Directory of Open Access Journals (Sweden)

    Shenoy Arvind

    2010-01-01

    Full Text Available In the last few decades, there have been tremendous advances in the mechanical properties and methods of fabrication of ceramic materials. While porcelain-based materials are still a major component of the market, there have been moves to replace metal ceramics systems with all ceramic systems. Advances in bonding techniques have increased the range and scope for use of ceramics in dentistry. In this brief review, we will discuss advances in ceramic materials and fabrication techniques. Examples of the microstructure property relationships for these ceramic materials will also be addressed.

  20. Dependence of Shear and Concentration on Fouling in a Membrane Bioreactor with Rotating Membrane Discs

    DEFF Research Database (Denmark)

    Jørgensen, Mads Koustrup; Pedersen, Malene Thostrup; Christensen, Morten Lykkegaard;

    2014-01-01

    Rotating ceramic membrane discs were fouled with lab-scale membrane bioreactors (MBR) sludge. Sludge filtrations were performed at varying rotation speeds and in different concentric rings of the membranes on different sludge concentrations. Data showed that the back transport expressed by limiti...

  1. Fatigue of dental ceramics

    OpenAIRE

    Zhang, Yu; Sailer, Irena; lawn, brian

    2013-01-01

    Clinical data on survival rates reveal that all-ceramic dental prostheses are susceptible to fracture from repetitive occlusal loading. The objective of this review is to examine the underlying mechanisms of fatigue in current and future dental ceramics

  2. Ceramic Laser Materials

    OpenAIRE

    Guillermo Villalobos; Jasbinder Sanghera; Ishwar Aggarwal; Bryan Sadowski; Jesse Frantz; Colin Baker; Brandon Shaw; Woohong Kim

    2012-01-01

    Ceramic laser materials have come a long way since the first demonstration of lasing in 1964. Improvements in powder synthesis and ceramic sintering as well as novel ideas have led to notable achievements. These include the first Nd:yttrium aluminum garnet (YAG) ceramic laser in 1995, breaking the 1 KW mark in 2002 and then the remarkable demonstration of more than 100 KW output power from a YAG ceramic laser system in 2009. Additional developments have included highly doped microchip lasers,...

  3. Emulsification using microporous membranes

    Directory of Open Access Journals (Sweden)

    Goran T. Vladisavljević

    2011-10-01

    Full Text Available Membrane emulsification is a process of injecting a pure dispersed phase or pre-emulsion through a microporous membrane into the continuous phase. As a result of the immiscibility of the two phases, droplets of the dispersed phase are formed at the outlets of membrane pores. The droplets formed in the process are removed from the membrane surface by applying cross-flow or stirring of the continuous phase or using a dynamic (rotating or vibrating membrane. The most commonly used membrane for emulsification is the Shirasu Porous Glass (SPG membrane, fabricated through spinodal decomposition in a melt consisting of Japanese volcanic ash (Shirasu, boric acid and calcium carbonate. Microsieve membranes are increasingly popular as an alternative to highly tortuous glass and ceramic membranes. Microsieves are usually fabricated from nickel by photolithography and electroplating or they can be manufactured from silicon nitride via Reactive Ion Etching (RIE. An advantage of microsieves compared to the SPG membrane is in much higher transmembrane fluxes and higher tolerance to fouling by the emulsion ingredients due to the existence of short, straight through pores. Unlike conventional emulsification devices such as high-pressure valve homogenisers and rotor-stator devices, membrane emulsification devices permit a precise control over the mean pore size over a wide range and during the process insignificant amount of energy is dissipated as heat. The drop size is primarily determined by the pore size, but it depends also on other parameters, such as membrane wettability, emulsion formulation, shear stress on the membrane surface, transmembrane pressure, etc.

  4. Thin film ceramic thermocouples

    Science.gov (United States)

    Gregory, Otto (Inventor); Fralick, Gustave (Inventor); Wrbanek, John (Inventor); You, Tao (Inventor)

    2011-01-01

    A thin film ceramic thermocouple (10) having two ceramic thermocouple (12, 14) that are in contact with each other in at least on point to form a junction, and wherein each element was prepared in a different oxygen/nitrogen/argon plasma. Since each element is prepared under different plasma conditions, they have different electrical conductivity and different charge carrier concentration. The thin film thermocouple (10) can be transparent. A versatile ceramic sensor system having an RTD heat flux sensor can be combined with a thermocouple and a strain sensor to yield a multifunctional ceramic sensor array. The transparent ceramic temperature sensor that could ultimately be used for calibration of optical sensors.

  5. Ion transport membrane module and vessel system

    Science.gov (United States)

    Stein, VanEric Edward; Carolan, Michael Francis; Chen, Christopher M.; Armstrong, Phillip Andrew; Wahle, Harold W.; Ohrn, Theodore R.; Kneidel, Kurt E.; Rackers, Keith Gerard; Blake, James Erik; Nataraj, Shankar; van Doorn, Rene Hendrik Elias; Wilson, Merrill Anderson

    2008-02-26

    An ion transport membrane system comprising (a) a pressure vessel having an interior, an exterior, an inlet, and an outlet; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region, wherein any inlet and any outlet of the pressure vessel are in flow communication with exterior regions of the membrane modules; and (c) one or more gas manifolds in flow communication with interior regions of the membrane modules and with the exterior of the pressure vessel.The ion transport membrane system may be utilized in a gas separation device to recover oxygen from an oxygen-containing gas or as an oxidation reactor to oxidize compounds in a feed gas stream by oxygen permeated through the mixed metal oxide ceramic material of the membrane modules.

  6. Development of Advanced Ceramic Manufacturing Technology

    Energy Technology Data Exchange (ETDEWEB)

    Pujari, V.K.

    2001-04-05

    Advanced structural ceramics are enabling materials for new transportation engine systems that have the potential for significantly reducing energy consumption and pollution in automobiles and heavy vehicles. Ceramic component reliability and performance have been demonstrated in previous U.S. DOE initiatives, but high manufacturing cost was recognized as a major barrier to commercialization. Norton Advanced Ceramics (NAC), a division of Saint-Gobain Industrial Ceramics, Inc. (SGIC), was selected to perform a major Advanced Ceramics Manufacturing Technology (ACMT) Program. The overall objectives of NAC's program were to design, develop, and demonstrate advanced manufacturing technology for the production of ceramic exhaust valves for diesel engines. The specific objectives were (1) to reduce the manufacturing cost by an order of magnitude, (2) to develop and demonstrate process capability and reproducibility, and (3) to validate ceramic valve performance, durability, and reliability. The program was divided into four major tasks: Component Design and Specification, Component Manufacturing Technology Development, Inspection and Testing, and Process Demonstration. A high-power diesel engine valve for the DDC Series 149 engine was chosen as the demonstration part for this program. This was determined to be an ideal component type to demonstrate cost-effective process enhancements, the beneficial impact of advanced ceramics on transportation systems, and near-term commercialization potential. The baseline valve material was NAC's NT451 SiAION. It was replaced, later in the program, by an alternate silicon nitride composition (NT551), which utilized a lower cost raw material and a simplified powder-processing approach. The material specifications were defined based on DDC's engine requirements, and the initial and final component design tasks were completed.

  7. Design of LTCC-based Ceramic Structure for Chemical Microreactor

    Directory of Open Access Journals (Sweden)

    D. Belavic

    2012-04-01

    Full Text Available The design of ceramic chemical microreactor for the production of hydrogen needed in portable polymer-electrolyte membrane (PEM fuel cells is presented. The microreactor was developed for the steam reforming of liquid fuels with water into hydrogen. The complex three-dimensional ceramic structure of the microreactor includes evaporator(s, mixer(s, reformer and combustor. Low-temperature co-fired ceramic (LTCC technology was used to fabricate the ceramic structures with buried cavities and channels, and thick-film technology was used to make electrical heaters, temperature sensors and pressure sensors. The final 3D ceramic structure consists of 45 LTCC tapes. The dimensions of the structure are 75 × 41 × 9 mm3 and the weight is about 73 g.

  8. Ceramic Nanocomposites from Tailor-Made Preceramic Polymers

    Directory of Open Access Journals (Sweden)

    Gabriela Mera

    2015-04-01

    Full Text Available The present Review addresses current developments related to polymer-derived ceramic nanocomposites (PDC-NCs. Different classes of preceramic polymers are briefly introduced and their conversion into ceramic materials with adjustable phase compositions and microstructures is presented. Emphasis is set on discussing the intimate relationship between the chemistry and structural architecture of the precursor and the structural features and properties of the resulting ceramic nanocomposites. Various structural and functional properties of silicon-containing ceramic nanocomposites as well as different preparative strategies to achieve nano-scaled PDC-NC-based ordered structures are highlighted, based on selected ceramic nanocomposite systems. Furthermore, prospective applications of the PDC-NCs such as high-temperature stable materials for thermal protection systems, membranes for hot gas separation purposes, materials for heterogeneous catalysis, nano-confinement materials for hydrogen storage applications as well as anode materials for secondary ion batteries are introduced and discussed in detail.

  9. Electrochemical Codeposition of Ceramic Nanocomposite Films

    OpenAIRE

    Toledano, Reut; Okner, Regina; Mandler, Daniel

    2007-01-01

    A novel method for deposition of ceramic nanocomposite films has been developed. This approach allows controlling the exact composition of the deposit, e.g., Cu-TiO2, Au-SiO2 and should enable the formation of a wide variety of coatings such as graded films, catalysts etc, in a straightforward approach. Sol-gel films are traditionally deposited via spin-coating, dip-coating or spraying. We describe a single step electrochemical deposition method for the preparation of ceramic nanocomposite fi...

  10. Advanced Hydrogen Transport Membranes for Vision 21 Fossil Fuel Plants

    Energy Technology Data Exchange (ETDEWEB)

    Carl R. Evenson; Shane E. Roark

    2006-03-31

    The objective of this project was to develop an environmentally benign, inexpensive, and efficient method for separating hydrogen from gas mixtures produced during industrial processes, such as coal gasification. A family of hydrogen separation membranes was developed including single phase mixed conducting ceramics, ceramic/ceramic composites, cermet membranes, cermet membranes containing a hydrogen permeable metal, and intermediate temperature composite layered membranes. Each membrane type had different operating parameters, advantages, and disadvantages that were documented over the course of the project. Research on these membranes progressed from ceramics to cermets to intermediate temperature composite layered membranes. During this progression performance was increased from 0.01 mL x min{sup -1} x cm{sup -2} up to 423 mL x min{sup -1} x cm{sup -2}. Eltron and team membranes not only developed each membrane type, but also membrane surface catalysis and impurity tolerance, creation of thin film membranes, alternative applications such as membrane promoted alkane dehydrogenation, demonstration of scale-up testing, and complete engineering documentation including process and mechanical considerations necessary for inclusion of Eltron membranes in a full scale integrated gasification combined cycle power plant. The results of this project directly led to a new $15 million program funded by the Department of Energy. This new project will focus exclusively on scale-up of this technology as part of the FutureGen initiative.

  11. Antibacterial ceramic for sandbox. Sunabayo kokin ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, K. (Ishizuka Glass Co. Ltd. Nagoya (Japan))

    1993-10-01

    Sands in sandboxes in parks have been called into question of being contaminated by colon bacilli and spawns from ascarides. This paper introduces an antibacterial ceramic for sandbox developed as a new material effective to help reduce the contamination. The ceramic uses natural sand as the main raw material, which is added with borax and silver to contain silver ions that have bacteria and fungus resistance and deodorizing effect. The ceramic has an average grain size ranging from 0.5 mm to 0.7 mm, and is so devised as to match specific gravity, grain size and shape of the sand, hence no separation and segregation can occur. The result of weatherability and antibacterial strength tests on sand for a sandbox mixed with the ceramic at 1% suggests that its efficacy lasts for about three years. Its actual use is under observation. Its efficacy has been verified in a test that measures a survival factor of spawns from dog ascardides contacted with aqueous solution containing the ceramic at 1%. Safety and sanitation tests have proved the ceramic a highly safe product that conforms to the food sanitation law. 5 refs., 3 figs., 3 tabs.

  12. Dissolution of tailored ceramic nuclear waste forms

    International Nuclear Information System (INIS)

    Dissolution experiments on polyphase, high alumina tailored ceramic nuclear waste forms developed for the chemical immobilization of Savannah River Plant nuclear waste are described. Three forms of leach tests have been adopted; bulk samples conforming to the Materials Characterization Center Static Leach Test (MCC-1), a powdered sample leach test, and a leach test performed on transmission electron microscope thin foil samples. From analysis of these tests the crystalline phases that preferentially dissolve on leaching and the product phases formed are identified and related to the tailoring and processing schemes used in forming the ceramics. The thin foil sample leaching enables the role of intergranular amorphous phases as short-circuit leaching paths in polyphase ceramics to be investigated

  13. Analyses of fine paste ceramics

    International Nuclear Information System (INIS)

    Four chapters are included: history of Brookhaven fine paste ceramics project, chemical and mathematical procedures employed in Mayan fine paste ceramics project, and compositional and archaeological perspectives on the Mayan fine paste ceramics

  14. Analyses of fine paste ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Sabloff, J A [ed.

    1980-01-01

    Four chapters are included: history of Brookhaven fine paste ceramics project, chemical and mathematical procedures employed in Mayan fine paste ceramics project, and compositional and archaeological perspectives on the Mayan fine paste ceramics. (DLC)

  15. Membrane processes in nuclear technologies

    International Nuclear Information System (INIS)

    to the pressure-driven processes, e.g. ultrafiltration and reverse osmosis, which were studied on a laboratory and pilot scale. Verification of the potential application of reverse osmosis on an industrial scale for treatment of liquid low- and intermediate-level radioactive wastes has been carried out with the installation particularly designed and constructed for the Department of Radioactive Waste Processing, Institute of Atomic Energy at Swierk. The thin-layer composite membranes made from a cross-linked aromatic polyamide of high retention of NaCl (99,4-99,7%) were applied in this process. It has been proved that a three-stage installation enables the radioactive waste of specific radioactivity below 105 Bq/dm3 to be cleaned down to 10 Bq/dm3 in permeate, with simultaneous 7-15-fold reduction of the activity in the concentrate. The results of own studies concerning the removal of selected radionuclides from model aqueous solutions and radioactive wastes with ultra-filtration enhanced by complexation and sorption were also presented in this work. In these cases, the mineral (ceramic) porous membranes made from a-alumina, titanium and zirconium oxides were applied. These membranes exhibited a high resistance against ionizing radiation, aggressive chemical environment and high temperatures. The high effectiveness of removal of the main components of liquid radioactive waste like 134Cs, 137Cs, 60Co, 124Sb, 85Sr, 152Eu and 154Eu with a hybrid ultrafiltration/complexation process has been experimentally proved. The effects of this type of complexing agent, its concentration and pH of the processed solution on the complexation effectiveness have been studied. Efficacy of the method was tested with real radioactive wastes. The monograph performs results of the studies on membrane distillation which has been proposed by the author for processing of liquid radioactive wastes, and the analysis of its applicability for nuclear desalination and the production of pure water

  16. Continuous Fiber Ceramic Composites

    Energy Technology Data Exchange (ETDEWEB)

    None

    2002-09-01

    Fiber-reinforced ceramic composites demonstrate the high-temperature stability of ceramics--with an increased fracture toughness resulting from the fiber reinforcement of the composite. The material optimization performed under the continuous fiber ceramic composites (CFCC) included a series of systematic optimizations. The overall goals were to define the processing window, to increase the robustinous of the process, to increase process yield while reducing costs, and to define the complexity of parts that could be fabricated.

  17. Alumina-based ceramic composite

    Science.gov (United States)

    Alexander, Kathleen B.; Tiegs, Terry N.; Becher, Paul F.; Waters, Shirley B.

    1996-01-01

    An improved ceramic composite comprising oxide ceramic particulates, nonoxide ceramic particulates selected from the group consisting of carbides, borides, nitrides of silicon and transition metals and mixtures thereof, and a ductile binder selected from the group consisting of metallic, intermetallic alloys and mixtures thereof is described. The ceramic composite is made by blending powders of the ceramic particulates and the ductile to form a mixture and consolidating the mixture of under conditions of temperature and pressure sufficient to produce a densified ceramic composite.

  18. Defect production in ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Zinkle, S.J. [Oak Ridge National Lab., TN (United States); Kinoshita, C. [Kyushu Univ. (Japan)

    1997-08-01

    A review is given of several important defect production and accumulation parameters for irradiated ceramics. Materials covered in this review include alumina, magnesia, spinel silicon carbide, silicon nitride, aluminum nitride and diamond. Whereas threshold displacement energies for many ceramics are known within a reasonable level of uncertainty (with notable exceptions being AIN and Si{sub 3}N{sub 4}), relatively little information exists on the equally important parameters of surviving defect fraction (defect production efficiency) and point defect migration energies for most ceramics. Very little fundamental displacement damage information is available for nitride ceramics. The role of subthreshold irradiation on defect migration and microstructural evolution is also briefly discussed.

  19. Defect production in ceramics

    International Nuclear Information System (INIS)

    A review is given of several important defect production and accumulation parameters for irradiated ceramics. Materials covered in this review include alumina, magnesia, spinel silicon carbide, silicon nitride, aluminum nitride and diamond. Whereas threshold displacement energies for many ceramics are known within a reasonable level of uncertainty (with notable exceptions being AIN and Si3N4), relatively little information exists on the equally important parameters of surviving defect fraction (defect production efficiency) and point defect migration energies for most ceramics. Very little fundamental displacement damage information is available for nitride ceramics. The role of subthreshold irradiation on defect migration and microstructural evolution is also briefly discussed

  20. Defect production in ceramics

    International Nuclear Information System (INIS)

    A review is given of several important defect production and accumulation parameters for irradiated ceramics. Materials covered in this review include alumina, magnesia, spinel, silicon carbide, silicon nitride, aluminum nitride and diamond. Whereas threshold displacement energies for many ceramics are known within a reasonable level of uncertainty (with notable exceptions being AlN and Si3N4), relatively little information exists on the equally important parameters of surviving defect fraction (defect production efficiency) and point defect migration energies for most ceramics. Very little fundamental displacement damage information is available for nitride ceramics. The role of subthreshold irradiation on defect migration and microstructural evolution is also briefly discussed. (orig.)

  1. Drugging Membrane Protein Interactions.

    Science.gov (United States)

    Yin, Hang; Flynn, Aaron D

    2016-07-11

    The majority of therapeutics target membrane proteins, accessible on the surface of cells, to alter cellular signaling. Cells use membrane proteins to transduce signals into cells, transport ions and molecules, bind cells to a surface or substrate, and catalyze reactions. Newly devised technologies allow us to drug conventionally "undruggable" regions of membrane proteins, enabling modulation of protein-protein, protein-lipid, and protein-nucleic acid interactions. In this review, we survey the state of the art of high-throughput screening and rational design in drug discovery, and we evaluate the advances in biological understanding and technological capacity that will drive pharmacotherapy forward against unorthodox membrane protein targets. PMID:26863923

  2. Membrane Protein Structure Determination: Back to the Membrane

    OpenAIRE

    Yao, Yong; Ding, Yi; Tian, Ye; Opella, Stanley J.; Marassi, Francesca M.

    2013-01-01

    NMR spectroscopy enables the structures of membrane proteins to be determined in the native-like environment of the phospholipid bilayer membrane. This chapter outlines the methods for membrane protein structural studies using solid-state NMR spectroscopy with samples of membrane proteins incorporated in proteoliposomes or planar lipid bilayers. The methods for protein expression and purification, sample preparation, and NMR experiments are described and illustrated with examples from OmpX an...

  3. Ceramic Ultrafiltration of Marine Algal Solutions: A Comprehensive Study

    KAUST Repository

    Dramas, Laure

    2014-09-01

    Algal bloom can significantly impact reverse osmosis desalination process and reduce the drinking water production. In 2008, a major bloom event forced several UAE reverse osmosis plants to stop their production, and in this context, a better understanding of UF membrane fouling caused by algal organic matter (AOM) is needed, in order to adjust the filtration conditions during algal bloom events. Polymeric MF/UF membranes are already widely used for RO pretreatment, but ceramic UF membranes can also be an alternative for the filtration of marine algal solutions. The fouling potential of the Red Sea and the Arabian Sea, sampled at different seasons, along with four algal monocultures grown in laboratory, and one mesocosm experiment in the Red Sea was investigated. Algal solutions induce a stronger and more irreversible fouling than terrestrial humic solution, toward ceramic membrane. During algal bloom events, this fouling is enhanced and becomes even more problematic at the decline phase of the bloom, for a similar initial DOC. Three main mechanisms are involved: the formation of a cake layer at the membrane surface; the penetration of the algal organic matter (AOM) in the pore network of the membrane; the strong adhesion of AOM with the membrane surface. The last mechanism is species-specific and metal-oxide specific. In order to understand the stronger ceramic UF fouling at the decline phase, AOM quality was analyzed every two days. During growth, AOM is getting enriched in High Molecular Weight (HMW) structures (> 200 kDa), which are mainly composed by proteins and polysaccharides, and these compounds seem to be responsible for the stronger fouling at decline phase. In order to prevent the fouling of ceramic membrane, coagulation-flocculation (CF) using ferric chloride was implemented prior to filtration. It permits a high removal of HMW compounds and greatly reduces the fouling potential of the algal solution. During brief algal bloom events, CF should be

  4. Ceramic Technology Project

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    The Ceramic Technology Project was developed by the USDOE Office of Transportation Systems (OTS) in Conservation and Renewable Energy. This project, part of the OTS's Materials Development Program, was developed to meet the ceramic technology requirements of the OTS's automotive technology programs. Significant accomplishments in fabricating ceramic components for the USDOE and NASA advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. These programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and data base and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine components commercially. A five-year project plan was developed with extensive input from private industry. In July 1990 the original plan was updated through the estimated completion of development in 1993. The objective is to develop the industrial technology base required for reliable ceramics for application in advanced automotive heat engines. The project approach includes determining the mechanisms controlling reliability, improving processes for fabricating existing ceramics, developing new materials with increased reliability, and testing these materials in simulated engine environments to confirm reliability. Although this is a generic materials project, the focus is on the structural ceramics for advanced gas turbine and diesel engines, ceramic bearings and attachments, and ceramic coatings for thermal barrier and wear applications in these engines. To facilitate the rapid transfer of this technology to US industry, the major portion of the work is being done in the ceramic industry, with technological support from government laboratories, other industrial laboratories, and universities.

  5. Hydrogen Production by Catalytic Partial Oxidation of Coke Oven Gas in BaCo0.7Fe0.3-xZrxO3-δ Ceramic Membrane Reactors

    Directory of Open Access Journals (Sweden)

    Yao Weilin

    2016-01-01

    Full Text Available The BaCo0.7Fe0.3-xZrxO3-δ (BCFZ, x = 0.04–0.12 mixed ionic–electronic conducting (MIEC membranes were synthesized with a sol–gel method and evaluated as potential membrane reactor materials for the partial oxidation of coke oven gas (COG. The effect of zirconium content on the phase structure, microstructure and performance of the BCFZ membrane under He or COG atmosphere were systemically investigated. The BaCo0.7Fe0.24Zr0.06O3-δ membrane exhibited the best oxygen permeability and good operation stability, which could be a potential candidate of the membrane materials for hydrogen production through the partial oxidation of COG.

  6. NASA/CARES dual-use ceramic technology spinoff applications

    Science.gov (United States)

    Powers, Lynn M.; Janosik, Lesley A.; Gyekenyesi, John P.; Nemeth, Noel N.

    1994-01-01

    NASA has developed software that enables American industry to establish the reliability and life of ceramic structures in a wide variety of 21st Century applications. Designing ceramic components to survive at higher temperatures than the capability of most metals and in severe loading environments involves the disciplines of statistics and fracture mechanics. Successful application of advanced ceramics material properties and the use of a probabilistic brittle material design methodology. The NASA program, known as CARES (Ceramics Analysis and Reliability Evaluation of Structures), is a comprehensive general purpose design tool that predicts the probability of failure of a ceramic component as a function of its time in service. The latest version of this software, CARESALIFE, is coupled to several commercially available finite element analysis programs (ANSYS, MSC/NASTRAN, ABAQUS, COSMOS/N4, MARC), resulting in an advanced integrated design tool which is adapted to the computing environment of the user. The NASA-developed CARES software has been successfully used by industrial, government, and academic organizations to design and optimize ceramic components for many demanding applications. Industrial sectors impacted by this program include aerospace, automotive, electronic, medical, and energy applications. Dual-use applications include engine components, graphite and ceramic high temperature valves, TV picture tubes, ceramic bearings, electronic chips, glass building panels, infrared windows, radiant heater tubes, heat exchangers, and artificial hips, knee caps, and teeth.

  7. Proton conducting cerate ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Coffey, G.W.; Pederson, L.R.; Armstrong, T.R.; Bates, J.L.; Weber, W.J. [Pacific Northwest Lab., Richland, WA (United States)

    1995-08-01

    Cerate perovskites of the general formula AM{sub x}Ce{sub 1-x}O{sub 3-{delta}}, where A = Sr or Ba and where M = Gd, Nd, Y, Yb or other rare earth dopant, are known to conduct a protonic current. Such materials may be useful as the electrolyte in a solid oxide fuel cell operating at intermediate temperatures, as an electrochemical hydrogen separation membrane, or as a hydrogen sensor. Conduction mechanisms in these materials were evaluated using dc cyclic voltammetry and mass spectrometry, allowing currents and activation energies for proton, electron, and oxygen ion contributions to the total current to be determined. For SrYb{sub 0.05}Ce{sub 0.95}O{sub 3-{delta}}, one of the best and most environmentally stable compositions, proton conduction followed two different mechanisms: a low temperature process, characterized by an activation energy of 0.42{+-}0.04 eV, and a high temperature process, characterized by an activation energy of 1.38{+-}0.13 eV. It is believed that the low temperature process is dominated by grain boundary conduction while bulk conduction is responsible for the high temperature process. The activation energy for oxygen ion conduction (0.97{+-}0.10 eV) agrees well with other oxygen conductors, while that for electronic conduction, 0.90{+-}0.09 eV, is affected by a temperature-dependent electron carrier concentration. Evaluated by direct measurement of mass flux through a dense ceramic with an applied dc field, oxygen ions were determined to be the majority charge carrier except at the lowest temperatures, followed by electrons and then protons.

  8. Integration Science and Technology of Silicon-Based Ceramics and Composites:Technical Challenges and Opportunities

    Science.gov (United States)

    Singh, M.

    2013-01-01

    Ceramic integration technologies enable hierarchical design and manufacturing of intricate ceramic and composite parts starting with geometrically simpler units that are subsequently joined to themselves and/or to metals to create components with progressively higher levels of complexity and functionality. However, for the development of robust and reliable integrated systems with optimum performance for high temperature applications, detailed understanding of various thermochemical and thermomechanical factors is critical. Different technical approaches are required for the integration of ceramic to ceramic and ceramic to metal systems. Active metal brazing, in particular, is a simple and cost-effective method to integrate ceramic to metallic components. Active braze alloys usually contain a reactive filler metal (e.g., Ti, Cr, V, Hf etc) that promotes wettability and spreading by inducing chemical reactions with the ceramics and composites. In this presentation, various examples of brazing of silicon nitride to themselves and to metallic systems are presented. Other examples of joining of ceramic composites (C/SiC and SiC/SiC) using ceramic interlayers and the resulting microstructures are also presented. Thermomechanical characterization of joints is presented for both types of systems. In addition, various challenges and opportunities in design, fabrication, and testing of integrated similar (ceramic-ceramic) and dissimilar (ceramic-metal) material systems will be discussed. Potential opportunities and need for the development of innovative design philosophies, approaches, and integrated system testing under simulated application conditions will also be presented.

  9. A review of water treatment membrane nanotechnologies

    KAUST Repository

    Pendergast, MaryTheresa M.

    2011-01-01

    Nanotechnology is being used to enhance conventional ceramic and polymeric water treatment membrane materials through various avenues. Among the numerous concepts proposed, the most promising to date include zeolitic and catalytic nanoparticle coated ceramic membranes, hybrid inorganic-organic nanocomposite membranes, and bio-inspired membranes such as hybrid protein-polymer biomimetic membranes, aligned nanotube membranes, and isoporous block copolymer membranes. A semi-quantitative ranking system was proposed considering projected performance enhancement (over state-of-the-art analogs) and state of commercial readiness. Performance enhancement was based on water permeability, solute selectivity, and operational robustness, while commercial readiness was based on known or anticipated material costs, scalability (for large scale water treatment applications), and compatibility with existing manufacturing infrastructure. Overall, bio-inspired membranes are farthest from commercial reality, but offer the most promise for performance enhancements; however, nanocomposite membranes offering significant performance enhancements are already commercially available. Zeolitic and catalytic membranes appear reasonably far from commercial reality and offer small to moderate performance enhancements. The ranking of each membrane nanotechnology is discussed along with the key commercialization hurdles for each membrane nanotechnology. © 2011 The Royal Society of Chemistry.

  10. Nanomaterial-Enabled Neural Stimulation.

    Science.gov (United States)

    Wang, Yongchen; Guo, Liang

    2016-01-01

    Neural stimulation is a critical technique in treating neurological diseases and investigating brain functions. Traditional electrical stimulation uses electrodes to directly create intervening electric fields in the immediate vicinity of neural tissues. Second-generation stimulation techniques directly use light, magnetic fields or ultrasound in a non-contact manner. An emerging generation of non- or minimally invasive neural stimulation techniques is enabled by nanotechnology to achieve a high spatial resolution and cell-type specificity. In these techniques, a nanomaterial converts a remotely transmitted primary stimulus such as a light, magnetic or ultrasonic signal to a localized secondary stimulus such as an electric field or heat to stimulate neurons. The ease of surface modification and bio-conjugation of nanomaterials facilitates cell-type-specific targeting, designated placement and highly localized membrane activation. This review focuses on nanomaterial-enabled neural stimulation techniques primarily involving opto-electric, opto-thermal, magneto-electric, magneto-thermal and acousto-electric transduction mechanisms. Stimulation techniques based on other possible transduction schemes and general consideration for these emerging neurotechnologies are also discussed. PMID:27013938

  11. Nanomaterial-enabled neural stimulation

    Directory of Open Access Journals (Sweden)

    Yongchen eWang

    2016-03-01

    Full Text Available Neural stimulation is a critical technique in treating neurological diseases and investigating brain functions. Traditional electrical stimulation uses electrodes to directly create intervening electric fields in the immediate vicinity of neural tissues. Second-generation stimulation techniques directly use light, magnetic fields or ultrasound in a non-contact manner. An emerging generation of non- or minimally invasive neural stimulation techniques is enabled by nanotechnology to achieve a high spatial resolution and cell-type specificity. In these techniques, a nanomaterial converts a remotely transmitted primary stimulus such as a light, magnetic or ultrasonic signal to a localized secondary stimulus such as an electric field or heat to stimulate neurons. The ease of surface modification and bio-conjugation of nanomaterials facilitates cell-type-specific targeting, designated placement and highly localized membrane activation. This review focuses on nanomaterial-enabled neural stimulation techniques primarily involving opto-electric, opto-thermal, magneto-electric, magneto-thermal and acousto-electric transduction mechanisms. Stimulation techniques based on other possible transduction schemes and general consideration for these emerging neurotechnologies are also discussed.

  12. 声强对板式陶瓷膜微滤超细TiO2悬浆液过程的影响%Effect of Acoustic Intensity on Plate Ceramic Membrane Microfiltration of Fine TiO2 Suspension

    Institute of Scientific and Technical Information of China (English)

    熊伟; 崔鹏; 印美娟; 王凤来; 陈亚中

    2012-01-01

    采用声强测量仪测量了超声发生器的声强分布,研究了声强对板式陶瓷膜错流微滤超细TiO2悬浆液性能的影响,以优化膜组件的位置.结果表明,声强在三维空间均存在不均匀分布,且声强是影响膜微滤性能的主要因素,滤饼层质量变化率R和超声强化因子E与声强呈近似正相关关系.膜面平均声强约0.5 W·cm-2时,R超过0.23,E可达1.2左右;平均声强约0.6 W·cm-2时,R超过04,E可达1.3左右.超声与膜微滤组合的优化方式为:膜组件同向放置于换能器上方并处于声场近场区内.%Distribution of acoustic intensity in ultrasonic generator was measured by ultrasonic power measuring meter. In order to optimize the location of membrane module in ultrasonic generator, effect of acoustic intensity on cross-flow microfiltration of fine TiO2 suspension with plate ceramic membrane was investigated. The results show that the distribution of acoustic intensity in three-dimensional space of ultrasonic generator is non-uniform, and acoustic intensity influences membrane microfiltration process significantly. The acoustic intensity is positively correlated with the mass change rate of cake layer R and the ultrasonic enhancement factor E. When the average acoustic intensity on membrane surface is about 0.5 W-cm , R is higher than 0.23 and E is about 1.2, and when the average acoustic intensity on membrane surface is about 0.6 Wcm"2, R is bigger than 0.4, and E is about 1.3. The optimized location found for ultrasonic-enhanced membrane microfiltration module is as follows: the ultrasonic irradiation direction is the same as the direction of permeation flux; membrane module is placed on top of the transducer and in the near field of the ultrasonic field.

  13. Prospects and problems of dense oxygen permeable membranes

    DEFF Research Database (Denmark)

    Hendriksen, P.V.; Larsen, P.H.; Mogensen, Mogens Bjerg;

    2000-01-01

    The prospects of using mixed ionic/electronic conducting ceramics for syngas production in a catalytic membrane reactor are analysed. Problems relating to limited thermodynamic stability and poor dimensional stability of candidate materials are addressed, The consequences for these problems...

  14. Development of thin film inorganic membranes for oxygen separation

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Hyo Jeong

    2012-08-22

    Membrane-based gas separation systems are noteworthy among technological options for carbon capture and storage (CCS), which is an important strategy to reduce CO{sub 2} emitted from point sources, e.g. mainly fossil power plants. In Oxyfuel-Combustion and Pre-Combustion of CCS power plant concepts oxygen separation from air is required. To meet this requirement oxygen transport membranes (OTM) consisting of gastight mixed ionic electronic conductors (MIEC) are proposed, which are associated with significantly lower efficiency losses compared with conventional air separation technologies. For cost effective application a maximum oxygen flux has to be achieved to reduce the membrane area. This can be met by reduction of membrane thickness. Therefore, the reduction of the membrane thickness to the micrometer range or even below is aimed in the present thesis. Ce{sub 0.8}Gd{sub 0.2}O{sub 2-{delta}} (CGO) with fluorite crystal structure and La{sub 0.58}Sr{sub 0.4}Co{sub 0.2}Fe{sub 0.8}O{sub 3-{delta}} (LSCF) with perovskite crystal structure were developed as thin film membrane. CGO is expected to be more stable than other potential MIEC membranes in reducing atmospheres and to achieve sufficient oxygen permeation, e.g. in syngas production or petrol chemistry. LSCF is expected to be highly permeable with an acceptable chemical stability in Oxyfuel-combustion. Various porous ceramic substrates were prepared by vacuum-slip-casting and warm-pressing, and then characterized for porosity, gas-permeability and surface roughness. Subsequently, two approaches to fabrication of thin film membranes were investigated, which are wetchemical deposition (WCD) and physical vapor deposition (PVD). For WCD, nano-dispersions and colloidal sols were prepared for membrane top-layer and/or interlayer. When CGO nano-dispersion (NDCGO) was spin-coated as thin film membrane, the gastightness of sintered membranes was increased with decrease in spinning time and increase in concentration of

  15. Hydrogen purifier module with membrane support

    Science.gov (United States)

    A hydrogen purifier utilizing a hydrogen-permeable membrane to purify hydrogen from mixed gases containing hydrogen is disclosed. Improved mechanical support for the permeable membrane is described, enabling forward or reverse differential pressurization of the membrane, which further stabilizes the membrane from wrinkling upon hydrogen uptake.

    2012-07-24

    A hydrogen purifier utilizing a hydrogen-permeable membrane to purify hydrogen from mixed gases containing hydrogen is disclosed. Improved mechanical support for the permeable membrane is described, enabling forward or reverse differential pressurization of the membrane, which further stabilizes the membrane from wrinkling upon hydrogen uptake.

  16. Organising to Enable Innovation

    DEFF Research Database (Denmark)

    Brink, Tove

    2016-01-01

    . The findings reveal a continous organising process between individual/ team creativity and organisational structures/control to enable innovation at firm level. Organising provides a dynamic approach and contains the integrated reconstruction of creativity, structures and boundaries for enhanced balance......The purpose of this conceptual paper is to reveal how organising can enable innovation across organisational layers and organisational units. This approach calls for a cross-disciplinary literature review. The aim is to provide an integrated understanding of innovation in an organisational approach...... of explorative and exploitative learning in uncertain environments. Shedding light on the cross-disciplinary theories to organise innovation provides a contribution at the firm level to enable innovation....

  17. Development of nanoporous TiO2 and SiC membranes for membrane filtration

    DEFF Research Database (Denmark)

    König, Katja; Vigna, Erika; Farsi, Ali;

    Reverse osmosis membranes are increasingly used for the production of drinking water (desalination of sea water or brackish water), for demineralisation of water in industrial processes (boiled feed water, microelectronics production) as well as in food processing and pharmaceutical production....... Today´s reverse osmosis membranes are made of polymers; however, these membranes have several technical limitations, for example, low water fluxes and high sensitivity to oxidizing chemicals. Since membrane fouling is still a major problem in reverse osmosis desalination plants, replacement of polymer...... reverse osmosis membranes by ceramic counterparts would provide higher fluxes and allow more efficient cleaning of the membranes. The aim of this work was to prepare defect-free nanoporous ceramic (TiO2 and SiC) layers on macroporous SiC supports by using electrophoretic deposition and dip...

  18. Multilayer sulfur-resistant composite metal membranes and methods of making and repairing the same

    Science.gov (United States)

    Way, J. Douglas; Hatlevik, Oyvind

    2014-07-15

    The invention relates to thin, hydrogen-permeable, sulfur-resistant membranes formed from multi-layers of palladium or palladium-alloy coatings on porous, ceramic or metal supports, methods of making these membranes, methods of repairing layers of these membranes and devices that incorporate these membranes.

  19. Structural stability and oxygen permeability of BaCo{sub 1−x}Nb{sub x}O{sub 3−δ} ceramic membranes for air separation

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Chengzhang, E-mail: wucz@shu.edu.cn [Shanghai Key Laboratory of Modern Metallurgy and Materials Processing, Shanghai University, Shanghai 200072 (China); Gai, Yongqian; Zhou, Jianfang; Tang, Xia; Zhang, Yunwen; Ding, Weizhong [Shanghai Key Laboratory of Modern Metallurgy and Materials Processing, Shanghai University, Shanghai 200072 (China); Sun, Chenghua [School of Chemistry, Monash University, Clayton, VIC 3800 (Australia)

    2015-07-25

    Highlights: • BCNx membranes with high oxygen permeation flux were prepared. • Oxygen permeability of BCNx membranes is stable at 900 °C. • Phase transition is governed by oxygen partial pressure and temperature. • Degradation mechanism of BCNx membrane is suggested. - Abstract: BaCo{sub 1−x}Nb{sub x}O{sub 3−δ} (BCNx, x = 0.1–0.2) membranes were synthesized through conventional solid-phase reactions. The introduction of niobium facilitates the formation of the cubic perovskite structure and decreases oxygen nonstoichiometry. BCNx membranes possess higher oxygen permeation flux compared with BaCo{sub 0.7}Fe{sub 0.2}Nb{sub 0.1}O{sub 3−δ} membrane at the same condition. A stable permeation flux as high as 2.61 ml cm{sup −2} min{sup −1} is obtained through BaCo{sub 0.9}Nb{sub 0.1}O{sub 3−δ} membrane at 900 °C under the Air/He gradient. Long-time permeation study shows that the oxygen fluxes of BCNx membranes are stable at 900 °C but degrade slowly with time at 850 °C. XRD and TG–DSC results indicate that the degradation behavior occured at 850 °C is due to the phase transition from the cubic perovskite to monoclinic or orthorhombic structure, which is governed by the oxygen partial pressure and temperature. The oxidation of cobalt ion is considered to be the nature for the phase transition, which makes the tolerance factor increasing and results in structural destabilization.

  20. Enabling distributed collaborative science

    DEFF Research Database (Denmark)

    Hudson, T.; Sonnenwald, Diane H.; Maglaughlin, K.;

    2000-01-01

    To enable collaboration over distance, a collaborative environment that uses a specialized scientific instrument called a nanoManipulator is evaluated. The nanoManipulator incorporates visualization and force feedback technology to allow scientists to see, feel, and modify biological samples being...

  1. The Nordic Housing Enabler

    DEFF Research Database (Denmark)

    Helle, T.; Nygren, C.; Slaug, B.;

    2014-01-01

    This study addresses development of a content-valid cross-Nordic version of the Housing Enabler and investigation of its inter-rater reliability when used in occupational therapy rating situations, involving occupational therapists, clients, and their home environments. The instrument was...

  2. Pilot project as enabler?

    DEFF Research Database (Denmark)

    Neisig, Margit; Glimø, Helle; Holm, Catrine Granzow;

    This article deals with a systemic perspective on transition. The field of study addressed is a pilot project as enabler of transition in a highly complex polycentric context. From a Luhmannian systemic approach, a framework is created to understand and address barriers of change occurred using...

  3. Industrial ceramics - Properties, forming and applications

    International Nuclear Information System (INIS)

    After a general introduction to ceramics (definition, general properties, elaboration, applications, market data), this book address conventional ceramics (elaboration, material types), thermo-structural ceramics (oxide based ceramics, non-oxide ceramics, fields of application, functional coatings), refractory ceramics, long fibre and ceramic matrix composites, carbonaceous materials, ceramics used for filtration, catalysis and the environment, ceramics for biomedical applications, ceramics for electronics and electrical engineering (for capacitors, magnetic, piezoelectric, dielectric ceramics, ceramics for hyper-frequency resonators), electrochemical ceramics, transparent ceramics (forming and sintering), glasses, mineral binders. The last chapter addresses ceramics used in the nuclear energy sector: in nuclear fuels and fissile material, absorbing ceramics and shields, in the management of nuclear wastes, new ceramics for reactors under construction or for future nuclear energy

  4. A STUDY ON MEMBRANE PROCESS WITH γ-ALUMINA MEMBRANE REACTOR FOR ETHYLBENZENE DEHYDROGENATION TO STYRENE

    Institute of Scientific and Technical Information of China (English)

    Chen Qingling; Xu Zhongqiang

    2001-01-01

    The membrane reaction of ethylbenzene(EB) dehydrogenation to styrene(ST) has been studied by using K2O/Fe2O3 industrial catalyst and γ-alumina ceramic membrane developed by our institute. In comparison with the packed bed reactor (that is, plug flow reactor, abbr. PFR) in industrial practice, the yield of styrene was increased by 5%~10% in the membrane reactor. Furthermore, mathematical modeling of membrane reaction has been studied to display the principle of optimal match between the catalytic activity and the membrane permeability.

  5. Nordic Housing Enabler

    DEFF Research Database (Denmark)

    Helle, Tina; Brandt, Åse

    2009-01-01

    Development and reliability testing of the Nordic Housing Enabler – an instrument for accessibility assessment of the physical housing. Tina Helle & Åse Brandt University of Lund, Health Sciences, Faculty of Medicine (SE) and University College Northern Jutland, Occupational Therapy department (DK......, however, the built environment shows serious deficits when it comes to accessibility. This study addresses development of a content valid cross-Nordic version of the Housing Enabler and investigation of inter-rater reliability, when used in occupational therapy practice. The instrument was translated from...... the original Swedish version and adapted according to accessibility norms and guidelines for housing design in Sweden, Denmark, Iceland and Finland. This iterative process involved occupational therapists, architects, building engineers and professional translators, resulting in the Nordic Housing...

  6. Spatially enabled land administration

    DEFF Research Database (Denmark)

    Enemark, Stig

    2006-01-01

    other words: Good governance and sustainable development is not attainable without sound land administration or - more broadly – sound land management. The paper presents a land management vision that incorporates the benefits of ICT enabled land administration functions. The idea is that spatial......Good governance is a qualitative term or an ideal which may be difficult to achieve. Different people, organisations, and government authorities will define “good governance” according to their own experience and interests. In any case, almost all kind of government includes a spatial component. In...... enabling of land administration systems managing tenure, valuation, planning, and development will allow the information generated by these activities to be much more useful. Also, the services available to private and public sectors and to community organisations should commensurably improve. Knowledge...

  7. Current Issues with Environmental Barrier Coatings for Ceramics and Ceramic Composites

    Science.gov (United States)

    Lee, Kang N.

    2004-01-01

    The environmental barrier coating (EBC) for SiC/SiC ceramic matrix composites and Si3N4 ceramics is an emerging field as the application of silicon-based ceramics in the gas turbine engine hot section is on the horizon, both for aero and industrial gas turbines. EBC is an enabling technology for silicon-based ceramics because these materials without an EBC cannot be used in combustion environments due to rapid surface recession. Significant progress in EBC development has been made during the last decade through various government-sponsored programs. Current EBCs are based on silicon, mullite (3Al2O3-2SiO2) and BSAS (barium strontium aluminum silicate with celsian structure). Volatility of BSAS, BSAS-silica chemical reaction, and low melting point of silicon limit temperature capability of current EBCs to about 1350 C for long-term applications. There is a need for higher temperature EBCs as the temperature capability of silicon-based ceramics continue to increase. Therefore, research is underway to develop EBCs with improved temperature capability compared to current EBCs. The current status and issues with the advanced EBC development efforts will be discussed.

  8. Ceramic Solar Receiver

    Science.gov (United States)

    Robertson, C., Jr.

    1984-01-01

    Solar receiver uses ceramic honeycomb matrix to absorb heat from Sun and transfer it to working fluid at temperatures of 1,095 degrees and 1,650 degrees C. Drives gas turbine engine or provides heat for industrial processes.

  9. Light emitting ceramic device

    Science.gov (United States)

    Valentine, Paul; Edwards, Doreen D.; Walker, Jr., William John; Slack, Lyle H.; Brown, Wayne Douglas; Osborne, Cathy; Norton, Michael; Begley, Richard

    2010-05-18

    A light-emitting ceramic based panel, hereafter termed "electroceramescent" panel, is herein claimed. The electroceramescent panel is formed on a substrate providing mechanical support as well as serving as the base electrode for the device. One or more semiconductive ceramic layers directly overlay the substrate, and electrical conductivity and ionic diffusion are controlled. Light emitting regions overlay the semiconductive ceramic layers, and said regions consist sequentially of a layer of a ceramic insulation layer and an electroluminescent layer, comprised of doped phosphors or the equivalent. One or more conductive top electrode layers having optically transmissive areas overlay the light emitting regions, and a multi-layered top barrier cover comprising one or more optically transmissive non-combustible insulation layers overlay said top electrode regions.

  10. Ceramic fiber filter technology

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, B.L.; Janney, M.A.

    1996-06-01

    Fibrous filters have been used for centuries to protect individuals from dust, disease, smoke, and other gases or particulates. In the 1970s and 1980s ceramic filters were developed for filtration of hot exhaust gases from diesel engines. Tubular, or candle, filters have been made to remove particles from gases in pressurized fluidized-bed combustion and gasification-combined-cycle power plants. Very efficient filtration is necessary in power plants to protect the turbine blades. The limited lifespan of ceramic candle filters has been a major obstacle in their development. The present work is focused on forming fibrous ceramic filters using a papermaking technique. These filters are highly porous and therefore very lightweight. The papermaking process consists of filtering a slurry of ceramic fibers through a steel screen to form paper. Papermaking and the selection of materials will be discussed, as well as preliminary results describing the geometry of papers and relative strengths.

  11. Enabling Wind Power Nationwide

    Energy Technology Data Exchange (ETDEWEB)

    Jose Zayas, Michael Derby, Patrick Gilman and Shreyas Ananthan,

    2015-05-01

    Leveraging this experience, the U.S. Department of Energy’s (DOE’s) Wind and Water Power Technologies Office has evaluated the potential for wind power to generate electricity in all 50 states. This report analyzes and quantifies the geographic expansion that could be enabled by accessing higher above ground heights for wind turbines and considers the means by which this new potential could be responsibly developed.

  12. Membrane protein structure determination: back to the membrane.

    Science.gov (United States)

    Yao, Yong; Ding, Yi; Tian, Ye; Opella, Stanley J; Marassi, Francesca M

    2013-01-01

    NMR spectroscopy enables the structures of membrane proteins to be determined in the native-like environment of the phospholipid bilayer membrane. This chapter outlines the methods for membrane protein structural studies using solid-state NMR spectroscopy with samples of membrane proteins incorporated in proteoliposomes or planar lipid bilayers. The methods for protein expression and purification, sample preparation, and NMR experiments are described and illustrated with examples from OmpX and Ail, two bacterial outer membrane proteins that function in bacterial virulence. PMID:23975776

  13. Reinforcement of ceramic materials

    International Nuclear Information System (INIS)

    In the commercial field, greater reproduceability of ceramic materials was achieved by systematic process control of the steps in manufacture. By improvement of the microstructure design, the strength and toughness against tearing of the materials were increased. The articles give a survey of theoretical and experimental results in manufacture and of the composition of ceramics with reinforced structure. Preferred materials are zirconium-, aluminium- and yttrium oxide, silicon oxide and -nitride and titanium- and silicon carbide. (DG)

  14. Statistic><Ceramics

    DEFF Research Database (Denmark)

    Hansen, Flemming Tvede

    2008-01-01

    Co-organizer for and participant at the exhibition: Statistic><Ceramics The Röhsska Museum of Design and Decorative Arts; Gothenborg 5/2-16/3 2008 Museum fur Kunst und Gewerbe, Hamburg 3/4-27/4 2008......Co-organizer for and participant at the exhibition: Statistic><Ceramics The Röhsska Museum of Design and Decorative Arts; Gothenborg 5/2-16/3 2008 Museum fur Kunst und Gewerbe, Hamburg 3/4-27/4 2008...

  15. Selecting Ceramics - Introduction

    OpenAIRE

    Cassidy, M.

    2002-01-01

    AIM OF PRESENTATION: To compare a number of materials for extracoronal restoration of teeth with particular reference to CAD-CAM ceramics. CASE DESCRIPTION AND TREATMENT CARRIED OUT: This paper will be illustrated using clinical examples of patients treated using different ceramic restorations to present the advantages and disadvantages and each technique. The different requirements of tooth preparation, impression taking and technical procedures of each system will be presented and compar...

  16. Environmental performance of ceramic tiles: Improvement proposals

    International Nuclear Information System (INIS)

    Ceramic tile is one of the most widely used materials in construction. Due to the increased demand for environmentally responsible construction and the ever more restrictive environmental requirements derived from the legislation, there is a need for a tool to enable the environmental behaviour of such material to be evaluated. By the application of the life cycle assessment (LCA) methodology, this study is focused on calculating indicators capable of measuring the environmental behaviour of ceramic tiles. Taking the production of 1 m2 of ceramic as a functional unit, the aim was to perform a life cycle inventory that covers all the stages from mining the red clay and atomising it to glaze manufacture and the production of the ceramic tiles and their delivery to customers. Next, the stages/materials/processes that have the greatest impact were identified, and a series of improvements were proposed with a view to enhancing the energetic efficiency of the firing process and minimising the emissions into the atmosphere, while at the same time reducing the noise pollution resulting from the pressing process. The environmental and economic feasibility of such a improvements was also studied.

  17. Membrane dynamics

    DEFF Research Database (Denmark)

    Bendix, Pól Martin

    2015-01-01

    Current topics include membrane-protein interactions with regard to membrane deformation or curvature sensing by BAR domains. Also, we study the dynamics of membrane tubes of both cells and simple model membrane tubes. Finally, we study membrane phase behavior which has important implications for...

  18. Ceramic electrolyte coating and methods

    Science.gov (United States)

    Seabaugh, Matthew M.; Swartz, Scott L.; Dawson, William J.; McCormick, Buddy E.

    2007-08-28

    Aqueous coating slurries useful in depositing a dense coating of a ceramic electrolyte material (e.g., yttrium-stabilized zirconia) onto a porous substrate of a ceramic electrode material (e.g., lanthanum strontium manganite or nickel/zirconia) and processes for preparing an aqueous suspension of a ceramic electrolyte material and an aqueous spray coating slurry including a ceramic electrolyte material. The invention also includes processes for depositing an aqueous spray coating slurry including a ceramic electrolyte material onto pre-sintered, partially sintered, and unsintered ceramic substrates and products made by this process.

  19. Clinical application of bio ceramics

    Science.gov (United States)

    Anu, Sharma; Gayatri, Sharma

    2016-05-01

    Ceramics are the inorganic crystalline material. These are used in various field such as biomedical, electrical, electronics, aerospace, automotive and optical etc. Bio ceramics are the one of the most active areas of research. Bio ceramics are the ceramics which are biocompatible. The unique properties of bio ceramics make them an attractive option for medical applications and offer some potential advantages over other materials. During the past three decades, a number of major advances have been made in the field of bio ceramics. This review focuses on the use of these materials in variety of clinical scenarios.

  20. Membranes in Lithium Ion Batteries

    OpenAIRE

    Junbo Hou; Min Yang

    2012-01-01

    Lithium ion batteries have proven themselves the main choice of power sources for portable electronics. Besides consumer electronics, lithium ion batteries are also growing in popularity for military, electric vehicle, and aerospace applications. The present review attempts to summarize the knowledge about some selected membranes in lithium ion batteries. Based on the type of electrolyte used, literature concerning ceramic-glass and polymer solid ion conductors, microporous filter type separa...

  1. Enabling Global Collaboration

    DEFF Research Database (Denmark)

    Brix, Anders; de Gier, Nicolai

    2014-01-01

    Traditional crafts still in existence and daily use in less industrialized countries, but to a great extend either extinct or deprived of meaning in the technologically 'developed' parts of the world, have an important role to play in creating the ’quality economy’ (Fry 2009). This involves...... recognizing the value of incremental refinement of tradition and sustainability obtained through cultivation of the culturally and visually sustainable. As a contribution to this development, we propose: 1) The notion of tectonics as a core concept enabling a mutual, cross-cultural design discourse, a...

  2. CtOS Enabler

    OpenAIRE

    Crespo Cepeda, Rodrigo; El Yamri El Khatibi, Meriem; Carrera García, Juan Manuel

    2015-01-01

    Las Smart Cities son, indudablemente, el futuro próximo de la tecnología al que nos acercamos cada día, lo que se puede observar en la abundancia de dispositivos móviles entre la población, que informatizan la vida cotidiana mediante el uso de la geolocalización y la información. Pretendemos unir estos dos ámbitos con CtOS Enabler para crear un estándar de uso que englobe todos los sistemas de Smart Cities y facilite a los desarrolladores de dicho software la creación de nuevas herramientas. ...

  3. Enabling Digital Literacy

    DEFF Research Database (Denmark)

    Ryberg, Thomas; Georgsen, Marianne

    2010-01-01

    There are some tensions between high-level policy definitions of “digital literacy” and actual teaching practice. We need to find workable definitions of digital literacy; obtain a better understanding of what digital literacy might look like in practice; and identify pedagogical approaches, which...... support teachers in designing digital literacy learning. We suggest that frameworks such as Problem Based Learning (PBL) are approaches that enable digital literacy learning because they provide good settings for engaging with digital literacy. We illustrate this through analysis of a case. Furthermore......, these operate on a meso-level mediating between high-level concepts of digital literacy and classroom practice....

  4. 臭氧/陶瓷膜对生物活性炭工艺性能和微生物群落结构影响%Influence of ozone/ceramic membrane on performance and microbial community in biological activated carbon filtration

    Institute of Scientific and Technical Information of China (English)

    郭建宁; 陈磊; 张锡辉; 王凌云; 陶益; 盛德洋

    2014-01-01

    Micro-polluted raw water was treated using a pilot plant with a scale of 120m3/d. The performance of ozone/ceramic membrane-biological activated carbon (BAC) process was studied. The diversity and detailed structure of microbial community of the microorganisms in BAC were also investigated. The hybrid process removed organic matter and ammonia effectively. The aeration with ozone-containing gas increased the dissolved oxygen in water flow and improved the removal of ammonia. The total removal efficiencies of ammonia and CODMn were 90% and 84%, respectively. The BAC played an important role in the final removals of pollutants. The microorganisms in the BAC bed were divided into 36phyla. Compared with the conventional BAC process, ozone/ceramic membrane in the hybrid process decreased the diversity and evenness of the microorganisms in the BAC. There were abundant Nitrosomonas and Nitrospira in the BAC in the hybrid process, which probably strengthen the ammonia removal. Moreover, the pathogenic bacteria and opportunistic pathogen were significantly inhibited by ozone/ceramic membrane, resulting in the decrease of their relative abundances in the following BAC. Therefore the biological safety of drinking water was enhanced significantly.%利用处理量为120m3/d的臭氧/陶瓷膜-生物活性炭(BAC)组合工艺处理微污染原水,对工艺性能和BAC中的微生物多样性和种群结构进行了研究。结果显示,组合工艺可有效去除微污染原水中的有机物和氨氮。臭氧曝气提高了溶解氧浓度,改善了后续 BAC 工艺对氨氮的去除效果。组合工艺对氨氮和CODMn的总去除率分别约为90%和84%,其中BAC在污染物的去除中发挥了重要作用。组合工艺和传统工艺中BAC床层共检测到36个门类的细菌。与传统BAC工艺相比,臭氧/陶瓷膜降低了后续BAC中微生物群落结构的多样性和均匀度。组合工艺BAC中存在丰度较高的亚硝化单胞菌属和硝化螺旋

  5. Membrane tension and peripheral protein density mediate membrane shape transitions

    OpenAIRE

    Shi, Zheng; Baumgart, Tobias

    2015-01-01

    Endocytosis is a ubiquitous eukaryotic membrane budding, vesiculation, and internalization process fulfilling numerous roles including compensation of membrane area increase after bursts of exocytosis. The mechanism of the coupling between these two processes to enable homeostasis is not well understood. Recently, an ultrafast endocytosis (UFE) pathway was revealed with a speed significantly exceeding classical clathrin-mediated endocytosis (CME). Membrane tension reduction is a potential mec...

  6. Development of New Generation of Ceramics for Environmentally Focused Chemical Separations

    Science.gov (United States)

    Ramakrishnan, Girish

    of this thesis focuses on development of a new generation of ceramic membranes utilizing thermal spray techniques to produce highly scalable and extremely cost effective filtration membranes. Thermal spray method of membrane manufacturing has the advantage of economic scalability (up to tens of square meters) along with performance enhancement as compared to conventional wet casting process. In addition to developing a proof of concept for this approach, several strategies on how to improve ceramic membranes' performance via spraying process optimization are also described. Specifically, several thermal sprayed Alumina membrane samples were prepared by varying different process parameters. These samples were characterized using known techniques and subjected to permeability and size exclusion tests to correlate spraying parameters with membranes' performance. The membrane samples showed excellent clean water flux comparable to commercially available membranes and had rejection rates up to 96%. These results show that the membranes produced in this research achieve outstanding performance at a fraction of the cost of commercially produced membrane, enabling the use of membrane filtrations units in developing countries.

  7. Enable, mediate, advocate.

    Science.gov (United States)

    Saan, Hans; Wise, Marilyn

    2011-12-01

    The authors of the Ottawa Charter selected the words enable, mediate and advocate to describe the core activities in what was, in 1986, the new Public Health. This article considers these concepts and the values and ideas upon which they were based. We discuss their relevance in the current context within which health promotion is being conducted, and discuss the implications of changes in the health agenda, media and globalization for practice. We consider developments within health promotion since 1986: its central role in policy rhetoric, the increasing understanding of complexities and the interlinkage with many other societal processes. So the three core activities are reviewed: they still fit well with the main health promotion challenges, but should be refreshed by new ideas and values. As the role of health promotion in the political arena has grown we have become part of the policy establishment and that is a mixed blessing. Making way for community advocates is now our challenge. Enabling requires greater sensitivity to power relations involved and an understanding of the role of health literacy. Mediating keeps its central role as it bridges vital interests of parties. We conclude that these core concepts in the Ottawa Charter need no serious revision. There are, however, lessons from the last 25 years that point to ways to address present and future challenges with greater sensitivity and effectiveness. We invite the next generation to avoid canonizing this text: as is true of every heritage, the heirs must decide on its use. PMID:22080073

  8. Smart Grid Enabled EVSE

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2014-10-15

    The combined team of GE Global Research, Federal Express, National Renewable Energy Laboratory, and Consolidated Edison has successfully achieved the established goals contained within the Department of Energy’s Smart Grid Capable Electric Vehicle Supply Equipment funding opportunity. The final program product, shown charging two vehicles in Figure 1, reduces by nearly 50% the total installed system cost of the electric vehicle supply equipment (EVSE) as well as enabling a host of new Smart Grid enabled features. These include bi-directional communications, load control, utility message exchange and transaction management information. Using the new charging system, Utilities or energy service providers will now be able to monitor transportation related electrical loads on their distribution networks, send load control commands or preferences to individual systems, and then see measured responses. Installation owners will be able to authorize usage of the stations, monitor operations, and optimally control their electricity consumption. These features and cost reductions have been developed through a total system design solution.

  9. Mixed oxygen ion/electron-conducting ceramics for oxygen separation

    Energy Technology Data Exchange (ETDEWEB)

    Stevenson, J.W.; Armstrong, T.R.; Armstrong, B.L. [Pacific Northwest National Lab., Richland, WA (United States)

    1996-08-01

    Mixed oxygen ion and electron-conducting ceramics are unique materials that can passively separate high purity oxygen from air. Oxygen ions move through a fully dense ceramic in response to an oxygen concentration gradient, charge-compensated by an electron flux in the opposite direction. Compositions in the system La{sub 1{minus}x}M{sub x}Co{sub 1{minus}y{minus}z}Fe{sub y}N{sub z}O{sub 3{minus}{delta}}, perovskites where M=Sr, Ca, and Ba, and N=Mn, Ni, Cu, Ti, and Al, have been prepared and their electrical, oxygen permeation, oxygen vacancy equilibria, and catalytic properties evaluated. Tubular forms, disks, and asymmetric membrane structures, a thin dense layer on a porous support of the same composition, have been fabricated for testing purposes. In an oxygen partial gradient, the passive oxygen flux through fully dense structures was highly dependent on composition. An increase in oxygen permeation with increased temperature is attributed to both enhanced oxygen vacancy mobility and higher vacancy populations. Highly acceptor-doped compositions resulted in oxygen ion mobilities more than an order of magnitude higher than yttria-stabilized zirconia. The mixed conducting ceramics have been utilized in a membrane reactor configuration to upgrade methane to ethane and ethylene. Conditions were established to balance selectivity and throughput in a catalytic membrane reactor constructed from mixed conducting ceramics.

  10. AGT 101: Ceramic component development: Advanced Gas Turbine Program: Topical report, October 1979-July 1987

    Energy Technology Data Exchange (ETDEWEB)

    Ten Eyck, M.O.; MacBeth, J.W.; Sweeting, T.B.

    1987-11-01

    This topical report summarizes the ceramic component technology development activity conducted by Standard Oil Engineered Materials Company. Standard Oil, acting as a principal subcontractor and supplier of ceramic components, directed its efforts toward the development of ceramic materials in the silicon-carbide family. Various shape forming and fabrication methods, and non-destructive evaluation techniques were explored to produce the static structural components for the ceramic engine. This enabled engine testing to proceed without program slippage, and developed the approaches for producing low-cost, production quantity processes. Standard Oil contributed to the acceptance of ceramics as a viable approach for automotive gas turbine engines and to the advancement of this vital ceramic technology. 174 figs., 33 tabs.

  11. Piezoelectric Ceramics and Their Applications

    Science.gov (United States)

    Flinn, I.

    1975-01-01

    Describes the piezoelectric effect in ceramics and presents a quantitative representation of this effect. Explains the processes involved in the manufacture of piezoelectric ceramics, the materials used, and the situations in which they are applied. (GS)

  12. Cooled Ceramic Turbine Vane Project

    Data.gov (United States)

    National Aeronautics and Space Administration — N&R Engineering will investigate the feasibility of cooled ceramics, such as ceramic matrix composite (CMC) turbine blade concepts that can decrease specific...

  13. Enabling graphene nanoelectronics.

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Wei; Ohta, Taisuke; Biedermann, Laura Butler; Gutierrez, Carlos; Nolen, C. M.; Howell, Stephen Wayne; Beechem Iii, Thomas Edwin; McCarty, Kevin F.; Ross, Anthony Joseph, III

    2011-09-01

    Recent work has shown that graphene, a 2D electronic material amenable to the planar semiconductor fabrication processing, possesses tunable electronic material properties potentially far superior to metals and other standard semiconductors. Despite its phenomenal electronic properties, focused research is still required to develop techniques for depositing and synthesizing graphene over large areas, thereby enabling the reproducible mass-fabrication of graphene-based devices. To address these issues, we combined an array of growth approaches and characterization resources to investigate several innovative and synergistic approaches for the synthesis of high quality graphene films on technologically relevant substrate (SiC and metals). Our work focused on developing the fundamental scientific understanding necessary to generate large-area graphene films that exhibit highly uniform electronic properties and record carrier mobility, as well as developing techniques to transfer graphene onto other substrates.

  14. Diffusion in ceramics

    CERN Document Server

    Pelleg, Joshua

    2016-01-01

    This textbook provides an introduction to changes that occur in solids such as ceramics, mainly at high temperatures, which are diffusion controlled, as well as presenting research data. Such changes are related to the kinetics of various reactions such as precipitation, oxidation and phase transformations, but are also related to some mechanical changes, such as creep. The book is composed of two parts, beginning with a look at the basics of diffusion according to Fick's Laws. Solutions of Fick’s second law for constant D, diffusion in grain boundaries and dislocations are presented along with a look at the atomistic approach for the random motion of atoms. In the second part, the author discusses diffusion in several technologically important ceramics. The ceramics selected are monolithic single phase ones, including: A12O3, SiC, MgO, ZrO2 and Si3N4. Of these, three refer to oxide ceramics (alumina, magnesia and zirconia). Carbide based ceramics are represented by the technologically very important Si-ca...

  15. Mechanical properties of ceramics

    CERN Document Server

    Pelleg, Joshua

    2014-01-01

    This book discusses the mechanical properties of ceramics and aims to provide both a solid background for undergraduate students, as well as serving as a text to bring practicing engineers up to date with the latest developments in this topic so they can use and apply these to their actual engineering work.  Generally, ceramics are made by moistening a mixture of clays, casting it into desired shapes and then firing it to a high temperature, a process known as 'vitrification'. The relatively late development of metallurgy was contingent on the availability of ceramics and the know-how to mold them into the appropriate forms. Because of the characteristics of ceramics, they offer great advantages over metals in specific applications in which hardness, wear resistance and chemical stability at high temperatures are essential. Clearly, modern ceramics manufacturing has come a long way from the early clay-processing fabrication method, and the last two decades have seen the development of sophisticated technique...

  16. Ceramic microstructure and adhesion

    Science.gov (United States)

    Buckley, D. H.

    1985-01-01

    When a ceramic is brought into contact with a ceramic, a polymer, or a metal, strong bond forces can develop between the materials. The bonding forces will depend upon the state of the surfaces, cleanliness and the fundamental properties of the two solids, both surface and bulk. Adhesion between a ceramic and another solid are discussed from a theoretical consideration of the nature of the surfaces and experimentally by relating bond forces to interface resulting from solid state contact. Surface properties of ceramics correlated with adhesion include, orientation, reconstruction and diffusion as well as the chemistry of the surface specie. Where a ceramic is in contact with a metal their interactive chemistry and bond strength is considered. Bulk properties examined include elastic and plastic behavior in the surficial regions, cohesive binding energies, crystal structures and crystallographic orientation. Materials examined with respect to interfacial adhesive interactions include silicon carbide, nickel zinc ferrite, manganese zinc ferrite, and aluminum oxide. The surfaces of the contacting solids are studied both in the atomic or molecularly clean state and in the presence of selected surface contaminants.

  17. Localized temperature stability of low temperature cofired ceramics

    Science.gov (United States)

    Dai, Steven Xunhu

    2013-11-26

    The present invention is directed to low temperature cofired ceramic modules having localized temperature stability by incorporating temperature coefficient of resonant frequency compensating materials locally into a multilayer LTCC module. Chemical interactions can be minimized and physical compatibility between the compensating materials and the host LTCC dielectrics can be achieved. The invention enables embedded resonators with nearly temperature-independent resonance frequency.

  18. Membrane fusion

    DEFF Research Database (Denmark)

    Bendix, Pól Martin

    2015-01-01

    At Stanford University, Boxer lab, I worked on membrane fusion of small unilamellar lipid vesicles to flat membranes tethered to glass surfaces. This geometry closely resembles biological systems in which liposomes fuse to plasma membranes. The fusion mechanism was studied using DNA zippering...... between complementary strands linked to the two apposing membranes closely mimicking the zippering mechanism of SNARE fusion complexes....

  19. Membrane tension and peripheral protein density mediate membrane shape transitions

    Science.gov (United States)

    Shi, Zheng; Baumgart, Tobias

    2015-01-01

    Endocytosis is a ubiquitous eukaryotic membrane budding, vesiculation and internalization process fulfilling numerous roles including compensation of membrane area increase after bursts of exocytosis. The mechanism of the coupling between these two processes to enable homeostasis is not well understood. Recently, an ultrafast endocytosis (UFE) pathway was revealed with a speed significantly exceeding classical clathrin-mediated endocytosis (CME). Membrane tension reduction is a potential mechanism by which endocytosis can be rapidly activated at remote sites. Here, we provide experimental evidence for a mechanism whereby membrane tension reduction initiates membrane budding and tubulation mediated by endocytic proteins, such as endophilin A1. We find that shape instabilities occur at well-defined membrane tensions and surface densities of endophilin. From our data, we obtain a membrane shape stability diagram that shows remarkable consistency with a quantitative model. This model applies to all laterally diffusive curvature-coupling proteins and therefore a wide range of endocytic proteins.

  20. Method of making a hydrogen transport membrane, and article

    Science.gov (United States)

    Schwartz, Joseph M.; Corpus, Joseph M.; Lim, Hankwon

    2015-07-21

    The present invention relates to a method of manufacturing a hydrogen transport membrane and the composite article itself. More specifically, the invention relates to producing a membrane substrate, wherein the ceramic substrate is coated with a metal oxide slurry, thereby eliminating the need for an activation step prior to plating the ceramic membrane through an electroless plating process. The invention also relates to modifying the pore size and porosity of the substrate by oxidation or reduction of the particles deposited by the metal oxide slurry.

  1. Ceramic vane drive joint

    Science.gov (United States)

    Smale, Charles H. (Inventor)

    1981-01-01

    A variable geometry gas turbine has an array of ceramic composition vanes positioned by an actuating ring coupled through a plurality of circumferentially spaced turbine vane levers to the outer end of a metallic vane drive shaft at each of the ceramic vanes. Each of the ceramic vanes has an end slot of bow tie configuration including flared end segments and a center slot therebetween. Each of the vane drive shafts has a cross head with ends thereof spaced with respect to the sides of the end slot to define clearance for free expansion of the cross head with respect to the vane and the cross head being configured to uniformly distribute drive loads across bearing surfaces of the vane slot.

  2. Análise do uso da membrana cerâmica de 0,2 μm na clarificação de cerveja = Analysis of the use of a 0.2 mm ceramic membrane for beer clarification

    Directory of Open Access Journals (Sweden)

    Tatiana Valesca Rodríguez Alicieo

    2008-07-01

    Full Text Available Neste trabalho são comparados o fluxo permeado e a qualidade do produto obtido na clarificação de cerveja por microfiltração tangencial, para uma membrana cerâmica tubular com tamanho nominal de poro de 0,2 mm na temperatura de 6 ± 1°C e pressões de 1, 2, 3 e 4 bar. Amostras do alimentado e permeado foram submetidas a análisesfísico-químicas. Além disso, foi realizado o estudo do mecanismo de fouling: bloqueio completo, bloqueio parcial e bloqueio interno de poros e formação de torta. Os resultados mostram redução de cor de 28,75% e de turbidez de 95,65% para a pressão de 4 bar. O estudo de fouling demonstrou que o mecanismo para a pressão de 1 e 3 bar foi o de bloqueio completo de poros e para a pressão de 2 e 4 bar o de formação de torta.This work compares the permeated flow and the quality of the obtainedproduct in the process of beer clarification by crossflow microfiltration. The membrane used in the present study was a tubular ceramic membrane with a 0.2 mm nominal pore diameter, at 6 ± 1°C and 1, 2, 3 and 4 bar of pressure. Samples of the feed and permeatewere analyzed. Additionally, the fouling mechanism was studied: complete, partial, internal blockade of pores and cake filtration. The results show a 28.75% reduction in color and 95.65% in turbidity at 4 bar. The study of fouling showed that the mechanism used for thepressures of 1 and 3 bar was the complete blockade of pores, whereas for the pressures of 2 and 4 bar, the cake formation was the mechanism used.

  3. Barium zirconate base ceramics

    International Nuclear Information System (INIS)

    The chemical corrosion at high temperatures is a serious problem in the refractory materials field, leading to degradation and bath contamination by elements of the refractory. The main objective of this work was to search for ceramics that could present higher resistance to chemical attack by aggressive molten oxides. The general behaviour of a ceramic material based on barium zirconate (Ba Zr O3) with the addition of different amounts of liquid phase former was investigated. The densification behaviour occurred during different heat treatments, as well as the microstructure development, as a function of the additives and their reactions with the main phase, were observed and are discussed. (author)

  4. Precision Finishing Of Ceramics

    Science.gov (United States)

    Bifano, T. G.; Blake, P. N.; Dow, T. A.; Scattergood, R. O.

    1987-01-01

    The manufacture of advanced ceramic components requires high accuracy and repeatibility in the control of the fabrication process. Surface finish in the nanometer range and excellent figure accuracy can be achieved if material can be removed from the surface without causing brittle fracture. To define the mechanism of "ductile" material removal, a series of experiments were initiated involving two processes: single-point diamond turning and diamond-wheel grinding. The results indicate that at small depths of cut, using stiff, well controlled machine tools, ceramic materials like silicon, silicon carbide, and germanium can be machined in a ductile regime.

  5. Oxygen-Permeable, Hydrophobic Membranes of Silanized alpha-Al2O3

    Science.gov (United States)

    Atwater, James E.; Akse, James R.

    2006-01-01

    Membranes made of silanized alumina have been prepared and tested as prototypes of derivatized ceramic membranes that are both highly permeable to oxygen and hydrophobic. Improved oxygen-permeable, hydrophobic membranes would be attractive for use in several technological disciplines, including supporting high-temperature aqueousphase oxidation in industrial production of chemicals, oxygenation of aqueous streams for bioreactors, and oxygenation of blood during open-heart surgery and in cases of extreme pulmonary dysfunction. In comparison with organic polymeric oxygen-permeable membranes now commercially available, the derivatized ceramic membranes are more chemically robust, are capable of withstanding higher temperatures, and exhibit higher oxygen-diffusion coefficients.

  6. Enabling distributed petascale science

    International Nuclear Information System (INIS)

    Petascale science is an end-to-end endeavour, involving not only the creation of massive datasets at supercomputers or experimental facilities, but the subsequent analysis of that data by a user community that may be distributed across many laboratories and universities. The new SciDAC Center for Enabling Distributed Petascale Science (CEDPS) is developing tools to support this end-to-end process. These tools include data placement services for the reliable, high-performance, secure, and policy-driven placement of data within a distributed science environment; tools and techniques for the construction, operation, and provisioning of scalable science services; and tools for the detection and diagnosis of failures in end-to-end data placement and distributed application hosting configurations. In each area, we build on a strong base of existing technology and have made useful progress in the first year of the project. For example, we have recently achieved order-of-magnitude improvements in transfer times (for lots of small files) and implemented asynchronous data staging capabilities; demonstrated dynamic deployment of complex application stacks for the STAR experiment; and designed and deployed end-to-end troubleshooting services. We look forward to working with SciDAC application and technology projects to realize the promise of petascale science

  7. Enabling immersive simulation.

    Energy Technology Data Exchange (ETDEWEB)

    McCoy, Josh (University of California Santa Cruz, Santa Cruz, CA); Mateas, Michael (University of California Santa Cruz, Santa Cruz, CA); Hart, Derek H.; Whetzel, Jonathan; Basilico, Justin Derrick; Glickman, Matthew R.; Abbott, Robert G.

    2009-02-01

    The object of the 'Enabling Immersive Simulation for Complex Systems Analysis and Training' LDRD has been to research, design, and engineer a capability to develop simulations which (1) provide a rich, immersive interface for participation by real humans (exploiting existing high-performance game-engine technology wherever possible), and (2) can leverage Sandia's substantial investment in high-fidelity physical and cognitive models implemented in the Umbra simulation framework. We report here on these efforts. First, we describe the integration of Sandia's Umbra modular simulation framework with the open-source Delta3D game engine. Next, we report on Umbra's integration with Sandia's Cognitive Foundry, specifically to provide for learning behaviors for 'virtual teammates' directly from observed human behavior. Finally, we describe the integration of Delta3D with the ABL behavior engine, and report on research into establishing the theoretical framework that will be required to make use of tools like ABL to scale up to increasingly rich and realistic virtual characters.

  8. CERAMIC WASTE FORM DATA PACKAGE

    Energy Technology Data Exchange (ETDEWEB)

    Amoroso, J.; Marra, J.

    2014-06-13

    The purpose of this data package is to provide information about simulated crystalline waste forms that can be used to select an appropriate composition for a Cold Crucible Induction Melter (CCIM) proof of principle demonstration. Melt processing, viscosity, electrical conductivity, and thermal analysis information was collected to assess the ability of two potential candidate ceramic compositions to be processed in the Idaho National Laboratory (INL) CCIM and to guide processing parameters for the CCIM operation. Given uncertainties in the CCIM capabilities to reach certain temperatures throughout the system, one waste form designated 'Fe-MP' was designed towards enabling processing and another, designated 'CAF-5%TM-MP' was designed towards optimized microstructure. Melt processing studies confirmed both compositions could be poured from a crucible at 1600{degrees}C although the CAF-5%TM-MP composition froze before pouring was complete due to rapid crystallization (upon cooling). X-ray diffraction measurements confirmed the crystalline nature and phase assemblages of the compositions. The kinetics of melting and crystallization appeared to vary significantly between the compositions. Impedance spectroscopy results indicated the electrical conductivity is acceptable with respect to processing in the CCIM. The success of processing either ceramic composition will depend on the thermal profiles throughout the CCIM. In particular, the working temperature of the pour spout relative to the bulk melter which can approach 1700{degrees}C. The Fe-MP composition is recommended to demonstrate proof of principle for crystalline simulated waste forms considering the current configuration of INL's CCIM. If proposed modifications to the CCIM can maintain a nominal temperature of 1600{degrees}C throughout the melter, drain, and pour spout, then the CAF-5%TM-MP composition should be considered for a proof of principle demonstration.

  9. Sol–gel template synthesis of luminescent glass–ceramic rods

    International Nuclear Information System (INIS)

    We report an original way to prepare luminescent glass–ceramic microrods containing Eu3+ doped BaF2 nanocrystals by sol–gel chemistry within the pores of a polycarbonate template membrane. Structural characterization by scanning electron microscopy and X-ray diffraction has shown the formation of glass–ceramic microrods with 0.8-m diameter of and 10 μm length in which BaF2 nanocrystals of about 30 nm size are embedded. Photoluminescence measurements have indicated the incorporation of Eu3+ ions inside the BaF2 nanocrystals in a broad range of sites with low coordination symmetry. The comparison made with the bulk glass–ceramic indicated an influence of the dimensional constraints imposed by the membrane pores during xerogel formation and subsequent glass ceramization.

  10. Enabling cleanup technology transfer

    International Nuclear Information System (INIS)

    Technology transfer in the environmental restoration, or cleanup, area has been challenging. While there is little doubt that innovative technologies are needed to reduce the times, risks, and costs associated with the cleanup of federal sites, particularly those of the Departments of Energy (DOE) and Defense, the use of such technologies in actual cleanups has been relatively limited. There are, of course, many reasons why technologies do not reach the implementation phase or do not get transferred from developing entities to the user community. For example, many past cleanup contracts provided few incentives for performance that would compel a contractor to seek improvement via technology applications. While performance-based contracts are becoming more common, they alone will not drive increased technology applications. This paper focuses on some applications of cleanup methodologies and technologies that have been successful and are illustrative of a more general principle. The principle is at once obvious and not widely practiced. It is that, with few exceptions, innovative cleanup technologies are rarely implemented successfully alone but rather are implemented in the context of enabling processes and methodologies. And, since cleanup is conducted in a regulatory environment, the stage is better set for technology transfer when the context includes substantive interactions with the relevant stakeholders. Examples of this principle are drawn from Argonne National Laboratory's experiences in Adaptive Sampling and Analysis Programs (ASAPs), Precise Excavation, and the DOE Technology Connection (TechCon) Program. The lessons learned may be applicable to the continuing challenges posed by the cleanup and long-term stewardship of radioactive contaminants and unexploded ordnance (UXO) at federal sites

  11. Porous polyoxadiazole membranes for harsh environment

    KAUST Repository

    Maab, Husnul

    2013-10-01

    A series of polyoxadiazoles with exceptionally high stability at temperatures as high as 370°C and in oxidative medium has been synthesized by polycondensation and manufactured into porous membranes by phase inversion. The membranes were characterized by thermal analysis (TGA), chemical stability was measured by immersion test, oxidative stability by Fenton\\'s test, pore diameter by porosimetry and the morphology by FESEM. The polymers are soluble only in sulfuric acid and are stable in organic solvents like NMP, THF and isopropanol. The membranes selectivity was confirmed by separation of polystyrene standards with different molecular weights. Most membranes were characterized as having a cut-off of 60,000. g/mol. Being stable under harsh environments, the membranes have incomparable characteristics with perspectives of application in chemical and pharmaceutical industry, catalytic reactors, in combination with oxidative processes and other applications so far envisioned only for ceramic membranes. © 2013.

  12. Prospects for nitrogen ceramics

    International Nuclear Information System (INIS)

    Nitrogen ceramics are predominant materials for engine components, and non-automotive applications - particularly for wear parts and molten-metal handling - are also set to flourish. High temperature strength and toughness are now adequate although long-term oxidation resistance is still a problem. The ability to join sialon pieces to make large complex components greatly widens the field of applications. (orig.)

  13. Toward virtual ceramic composites

    OpenAIRE

    Genet, Martin; LADEVEZE, Pierre; LUBINEAU, Gilles

    2016-01-01

    A first step toward a multi-scale and multi-physic model --a virtual material-- for self-healing ceramic matrix composites is presented. Each mechanism --mechanical, chemical-- that act on the material's lifetime at a given scale --fibre, yarn-- is introduced in a single modeling framework, aimed at providing powerful prediction tools.

  14. Digital Crafting in the field of Ceramics

    DEFF Research Database (Denmark)

    Hansen, Flemming Tvede; Evers, Henrik Leander; Tamke, Martin

    2015-01-01

    This article aims to discuss and explore how craft knowledge in the field of ceramics can be utilized through digital technologies. Based on a set of experiments, which led to the development of a computational system that negotiates between the movement of the designer’s hands and the 3d clay...... printing, we propose to leave thinking in diametric positions about technology and craft. Instead, we recommend to see technology as an enabling force and follow McCullough’s (1998) idea about a close connection between digital work and craft practice. We base this on similarities we find between the way...

  15. Caratterizzazione di membrane metalliche e ionomeriche per applicazioni energetiche

    OpenAIRE

    Catalano, Jacopo

    2009-01-01

    The work of this thesis has been focused on the characterization of metallic membranes for the hydrogen purification from steam reforming process and also of perfluorosulphonic acid ionomeric (PFSI) membranes suitable as electrolytes in fuel cell applications. The experimental study of metallic membranes was divided in three sections: synthesis of palladium and silver palladium coatings on porous ceramic support via electroless deposition (ELD), solubility and diffusivity analysis of hydr...

  16. Ceramic tubesheet design analysis

    Energy Technology Data Exchange (ETDEWEB)

    Mallett, R.H.; Swindeman, R.W.

    1996-06-01

    A transport combustor is being commissioned at the Southern Services facility in Wilsonville, Alabama to provide a gaseous product for the assessment of hot-gas filtering systems. One of the barrier filters incorporates a ceramic tubesheet to support candle filters. The ceramic tubesheet, designed and manufactured by Industrial Filter and Pump Manufacturing Company (EF&PM), is unique and offers distinct advantages over metallic systems in terms of density, resistance to corrosion, and resistance to creep at operating temperatures above 815{degrees}C (1500{degrees}F). Nevertheless, the operational requirements of the ceramic tubesheet are severe. The tubesheet is almost 1.5 m in (55 in.) in diameter, has many penetrations, and must support the weight of the ceramic filters, coal ash accumulation, and a pressure drop (one atmosphere). Further, thermal stresses related to steady state and transient conditions will occur. To gain a better understanding of the structural performance limitations, a contract was placed with Mallett Technology, Inc. to perform a thermal and structural analysis of the tubesheet design. The design analysis specification and a preliminary design analysis were completed in the early part of 1995. The analyses indicated that modifications to the design were necessary to reduce thermal stress, and it was necessary to complete the redesign before the final thermal/mechanical analysis could be undertaken. The preliminary analysis identified the need to confirm that the physical and mechanical properties data used in the design were representative of the material in the tubesheet. Subsequently, few exploratory tests were performed at ORNL to evaluate the ceramic structural material.

  17. Ceramic Laser Materials

    Energy Technology Data Exchange (ETDEWEB)

    Soules, T F; Clapsaddle, B J; Landingham, R L; Schaffers, K I

    2005-02-15

    Transparent ceramic materials have several major advantages over single crystals in laser applications, not the least of which is the ability to make large aperture parts in a robust manufacturing process. After more than a decade of working on making transparent YAG:Nd, Japanese workers have recently succeeded in demonstrating samples that performed as laser gain media as well as their single crystal counterparts. Since then several laser materials have been made and evaluated. For these reasons, developing ceramic laser materials is the most exciting and futuristic materials topic in today's major solid-state laser conferences. We have established a good working relationship with Konoshima Ltd., the Japanese producer of the best ceramic laser materials, and have procured and evaluated slabs designed by us for use in our high-powered SSHCL. Our measurements indicate that these materials will work in the SSHCL, and we have nearly completed retrofitting the SSHCL with four of the largest transparent ceramic YAG:Nd slabs in existence. We have also begun our own effort to make this material and have produced samples with various degrees of transparency/translucency. We are in the process of carrying out an extensive design-of-experiments to establish the significant process variables for making transparent YAG. Finally because transparent ceramics afford much greater flexibility in the design of lasers, we have been exploring the potential for much larger apertures, new materials, for example for the Mercury laser, other designs for SSHL, such as, edge pumping designs, slabs with built in ASE suppression, etc. This work has just beginning.

  18. FOILFEST :community enabled security.

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Judy Hennessey; Johnson, Curtis Martin; Whitley, John B.; Drayer, Darryl Donald; Cummings, John C., Jr. (.,; .)

    2005-09-01

    The Advanced Concepts Group of Sandia National Laboratories hosted a workshop, ''FOILFest: Community Enabled Security'', on July 18-21, 2005, in Albuquerque, NM. This was a far-reaching look into the future of physical protection consisting of a series of structured brainstorming sessions focused on preventing and foiling attacks on public places and soft targets such as airports, shopping malls, hotels, and public events. These facilities are difficult to protect using traditional security devices since they could easily be pushed out of business through the addition of arduous and expensive security measures. The idea behind this Fest was to explore how the public, which is vital to the function of these institutions, can be leveraged as part of a physical protection system. The workshop considered procedures, space design, and approaches for building community through technology. The workshop explored ways to make the ''good guys'' in public places feel safe and be vigilant while making potential perpetrators of harm feel exposed and convinced that they will not succeed. Participants in the Fest included operators of public places, social scientists, technology experts, representatives of government agencies including DHS and the intelligence community, writers and media experts. Many innovative ideas were explored during the fest with most of the time spent on airports, including consideration of the local airport, the Albuquerque Sunport. Some provocative ideas included: (1) sniffers installed in passage areas like revolving door, escalators, (2) a ''jumbotron'' showing current camera shots in the public space, (3) transparent portal screeners allowing viewing of the screening, (4) a layered open/funnel/open/funnel design where open spaces are used to encourage a sense of ''communitas'' and take advantage of citizen ''sensing'' and funnels are technological

  19. Exchange reaction of hydrogen isotopes on proton conductor ceramic of hydrogen pump for blanket tritium recovery system

    International Nuclear Information System (INIS)

    Electrochemical hydrogen pump using ceramic proton conductor has been investigated to discuss its application for the blanket tritium recovery system of the nuclear fusion reactor. As the series of those work, the transportation experiments of H2-D2 mixture via ceramic proton conductor membrane have been carried out. Then, the phenomenon that was caused by the exchange reaction between the deuterium in the ceramic and the hydrogen in the gas phase has been observed. So, the ceramic proton conductor which doped deuterium was exposed to hydrogen under the control of zero current, and the effluent gas was analyzed. It is considered that the hydrogen in the gas phase is taken as proton to the ceramic by isotope exchange reaction, and penetrates to the ceramic by diffusion with replacement of deuteron. (author)

  20. Centrifugal membrane filtration - Task 9

    International Nuclear Information System (INIS)

    The Energy and Environmental Research Center (EERC) has teamed with SpinTek Membrane Systems, Inc., the developer of a centrifugal membrane filtration technology, to demonstrate applications for the SpinTek technology within the US Department of Energy (DOE) Environmental management (EM) Program. The technology uses supported microporous membranes rotating at high rpm, under pressure, to separate suspended and colloidal solids from liquid streams, yielding a solids-free permeate stream and a highly concentrated solids stream. This is a crosscutting technology that falls under the Efficient Separations and Processing Crosscutting Program, with potential application to tank wastes, contaminated groundwater, landfill leachate, and secondary liquid waste streams from other remediation processes, including decontamination and decommissioning systems. Membrane-screening tests were performed with the SpinTek STC-X4 static test cell filtration unit, using five ceramic membranes with different pore size and composition. Based on permeate flux, a 0.25-microm TiO2/Al2O3 membrane was selected for detailed performance evaluation using the SpinTek ST-IIL centrifugal membrane filtration unit with a surrogate tank waste solution. An extended test run of 100 hr performed on a surrogate tank waste solution showed some deterioration in filtration performance, based on flux, apparently due to the buildup of solids near the inner portion of the membrane where relative membrane velocities were low. Continued testing of the system will focus on modifications to the shear pattern across the entire membrane surface to affect improved long-term performance

  1. Gas separation with glass membranes

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, D.L.; Abraham, L.C.; Blum, Y.; Way, J.D.

    1992-05-01

    The Department of Energy (DOE) is seeking to develop high temperature, high pressure inorganic membrane technology to perform a variety of gas separation processes to improve the efficiency and economics of advanced power generation systems such as direct coal-fueled turbines (DCFT) and the integrated gasification combined cycle process (IGCC). The temperatures encountered in these power generation systems are far above the temperature range for organic membrane materials. Inorganic materials such as ceramics are therefore the most likely membrane materials for use at high temperatures. This project focussed on silica glass fiber membranes made by PPG Industries (Pittsburgh, PA). The goals were both experimental and theoretical. The first objective was to develop a rational theory for the performance of these membranes. With existing theories as a starting point, a new theory was devised to explain the unusual molecular sieving'' behavior exhibited by these glass membranes. An apparatus was then devised for making permeation performance measurements at conditions of interest to DOE (temperatures to 2000[degrees]F; pressures to 1000 psia). With this apparatus, gas mixtures could be made typical of coal combustion or coal gasification processes, these gases could be passed into a membrane test cell, and the separation performance determined. Data were obtained for H[sub 2]/CO,N[sub 2]/CO[sub 2], 0[sub 2]/N[sub 2], and NH[sub 3]/N[sub 2] mixtures and for a variety of pure component gases (He, H[sub 2], CO[sub 2], N[sub 2], CO, NH[sub 3]). The most challenging part of the project turned out to be the sealing of the membrane at high temperatures and pressures. The report concludes with an overview of the practical potential of these membranes and of inorganic membranes in general of DOE and other applications.

  2. Mn oxide coated catalytic membranes for a hybrid ozonation-membrane filtration: comparison of Ti, Fe and Mn oxide coated membranes for water quality.

    Science.gov (United States)

    Byun, S; Davies, S H; Alpatova, A L; Corneal, L M; Baumann, M J; Tarabara, V V; Masten, S J

    2011-01-01

    In this study the performance of catalytic membranes in a hybrid ozonation-ceramic membrane filtration system was investigated. The catalytic membranes were produced by coating commercial ceramic ultrafiltration membranes with manganese or iron oxide nanoparticles using a layer-by-layer self-assembly technique. A commercial membrane with a titanium oxide filtration layer was also evaluated. The performance of the coated and uncoated membranes was evaluated using water from a borderline eutrophic lake. The permeate flux and removal of the organic matter was found to depend on the type of the metal oxide present on the membrane surface. The performance of the manganese oxide coated membrane was superior to that of the other membranes tested, showing the fastest recovery in permeate flux when ozone was applied and the greatest reduction in the total organic carbon (TOC) in the permeate. The removal of trihalomethanes (THMs) and haloacetic acids (HAAs) precursors using the membrane coated 20 times with manganese oxide nanoparticles was significantly better than that for the membranes coated with 30 or 40 times with manganese oxide nanoparticles or 40 times with iron oxide nanoparticles. PMID:20822791

  3. Grain boundaries in ceramics and ceramic-metal interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, D.R.; Wolf, D.

    1986-01-01

    Three interfaces exist: the crystal-crystal grain boundary in very pure single-phase ceramics, the crystal-glass-crystal grain boundary in most single-phase and polyphase ceramics, and the ceramic-metal interface. It is needed to correlate their structure and adhesion/failure. Methods for studying the bonding, interfacial structure, and fracture and adhesion are discussed, and recommendations are given. 42 refs. (DLC)

  4. Rheological Behaviour of Ceramic Inks for Direct Ceramic Inkjet Printing

    OpenAIRE

    P. Ponnambalam; Ramakrishnan, N.; P.K. Rajesh; K. Prakasan

    2006-01-01

    In this paper, studies were made on the preparation of ceramic inks with: (i) alumina powderin ethyl alcohol and (ii) zirconia powder in ethyl alcohol at different volume fractions of ceramic.Different amounts (0.75-3.00 vol %) of an organic dispersant (oleic acid) were added to ceramicink containing 5 per cent of ceramic by volume in ethyl alcohol. The viscosities of the suspensionswere determined with Brookefield viscometer (model: DV-E), which is suitable for measuringthe viscosities of su...

  5. Ceramic Stereolithography: Additive Manufacturing for Ceramics by Photopolymerization

    Science.gov (United States)

    Halloran, John W.

    2016-07-01

    Ceramic stereolithography and related additive manufacturing methods involving photopolymerization of ceramic powder suspensions are reviewed in terms of the capabilities of current devices. The practical fundamentals of the cure depth, cure width, and cure profile are related to the optical properties of the monomer, ceramic, and photo-active components. Postpolymerization steps, including harvesting and cleaning the objects, binder burnout, and sintering, are discussed and compared with conventional methods. The prospects for practical manufacturing are discussed.

  6. Integrally cored ceramic investment casting mold fabricated by ceramic stereolithography

    Science.gov (United States)

    Bae, Chang-Jun

    Superalloy airfoils are produced by investment casting (IC), which uses ceramic cores and wax patterns with ceramic shell molds. Hollow cored superalloy airfoils in a gas turbine engine are an example of complex IC parts. The complex internal hollow cavities of the airfoil are designed to conduct cooling air through one or more passageways. These complex internal passageways have been fabricated by a lost wax process requiring several processing steps; core preparation, injection molding for wax pattern, and dipping process for ceramic shell molds. Several steps generate problems such as high cost and decreased accuracy of the ceramic mold. For example, costly tooling and production delay are required to produce mold dies for complex cores and wax patterns used in injection molding, resulting in a big obstacle for prototypes and smaller production runs. Rather than using separate cores, patterns, and shell molds, it would be advantageous to directly produce a mold that has the casting cavity and the ceramic core by one process. Ceramic stereolithography (CerSLA) can be used to directly fabricate the integrally cored ceramic casting mold (ICCM). CerSLA builds ceramic green objects from CAD files from many thin liquid layers of powder in monomer, which are solidified by polymerization with a UV laser, thereby "writing" the design for each slice. This dissertation addresses the integrally cored casting ceramic mold (ICCM), the ceramic core with a ceramic mold shell in a single patternless construction, fabricated by ceramic stereolithography (CerSLA). CerSLA is considered as an alternative method to replace lost wax processes, for small production runs or designs too complex for conventional cores and patterns. The main topic is the development of methods to successfully fabricate an ICCM by CerSLA from refractory silica, as well as related issues. The related issues are the segregation of coarse fused silica powders in a layer, the degree of segregation parameter to

  7. CVD COATING OF CERAMIC LAYERS ON CERAMIC CUTTING TOOL MATERIALS

    OpenAIRE

    Porat, R.

    1991-01-01

    When forming cutting tool materials based on ceramic components, one must take into considration the combination of wear resistance and mechanical properties which can withstand unfavorable cutting conditions at the same time maintaining high strength and fracture toughness. Ceramic cutting tools which are designed for machining at high cutting speeds and which have high strength and fracture toughness can be formed by applying a thin layer of ceramic materials on the substrate in order to in...

  8. Integration Science and Technology of Advanced Ceramics for Energy and Environmental Applications

    Science.gov (United States)

    Singh, M.

    2012-01-01

    The discovery of new and innovative materials has been known to culminate in major turning points in human history. The transformative impact and functional manifestation of new materials have been demonstrated in every historical era by their integration into new products, systems, assemblies, and devices. In modern times, the integration of new materials into usable products has a special relevance for the technological development and economic competitiveness of industrial societies. Advanced ceramic technologies dramatically impact the energy and environmental landscape due to potential wide scale applications in all aspects of energy production, storage, distribution, conservation, and efficiency. Examples include gas turbine propulsion systems, fuel cells, thermoelectrics, photovoltaics, distribution and transmission systems based on superconductors, nuclear power generation, and waste disposal. Robust ceramic integration technologies enable hierarchical design and manufacturing of intricate ceramic components starting with geometrically simpler units that are subsequently joined to themselves and/or to metals to create components with progressively higher levels of complexity and functionality. However, for the development of robust and reliable integrated systems with optimum performance under different operating conditions, the detailed understanding of various thermochemical and thermomechanical factors is critical. Different approaches are required for the integration of ceramic-metal and ceramic-ceramic systems across length scales (macro to nano). In this presentation, a few examples of integration of ceramic to metals and ceramic to ceramic systems will be presented. Various challenges and opportunities in design, fabrication, and testing of integrated similar (ceramic-ceramic) and dissimilar (ceramic-metal) material systems will be discussed. Potential opportunities and need for the development of innovative design philosophies, approaches, and

  9. 3D Membrane Imaging and Porosity Visualization

    KAUST Repository

    Sundaramoorthi, Ganesh

    2016-03-03

    Ultrafiltration asymmetric porous membranes were imaged by two microscopy methods, which allow 3D reconstruction: Focused Ion Beam and Serial Block Face Scanning Electron Microscopy. A new algorithm was proposed to evaluate porosity and average pore size in different layers orthogonal and parallel to the membrane surface. The 3D-reconstruction enabled additionally the visualization of pore interconnectivity in different parts of the membrane. The method was demonstrated for a block copolymer porous membrane and can be extended to other membranes with application in ultrafiltration, supports for forward osmosis, etc, offering a complete view of the transport paths in the membrane.

  10. Membrane Biophysics

    CERN Document Server

    Ashrafuzzaman, Mohammad

    2013-01-01

    Physics, mathematics and chemistry all play a vital role in understanding the true nature and functioning of biological membranes, key elements of living processes. Besides simple spectroscopic observations and electrical measurements of membranes we address in this book the phenomena of coexistence and independent existence of different membrane components using various theoretical approaches. This treatment will be helpful for readers who want to understand biological processes by applying both simple observations and fundamental scientific analysis. It provides a deep understanding of the causes and effects of processes inside membranes, and will thus eventually open new doors for high-level pharmaceutical approaches towards fighting membrane- and cell-related diseases.

  11. Positron annihilation in transparent ceramics

    Science.gov (United States)

    Husband, P.; Bartošová, I.; Slugeň, V.; Selim, F. A.

    2016-01-01

    Transparent ceramics are emerging as excellent candidates for many photonic applications including laser, scintillation and illumination. However achieving perfect transparency is essential in these applications and requires high technology processing and complete understanding for the ceramic microstructure and its effect on the optical properties. Positron annihilation spectroscopy (PAS) is the perfect tool to study porosity and defects. It has been applied to investigate many ceramic structures; and transparent ceramics field may be greatly advanced by applying PAS. In this work positron lifetime (PLT) measurements were carried out in parallel with optical studies on yttrium aluminum garnet transparent ceramics in order to gain an understanding for their structure at the atomic level and its effect on the transparency and light scattering. The study confirmed that PAS can provide useful information on their microstructure and guide the technology of manufacturing and advancing transparent ceramics.

  12. Ceramic Composite Thin Films

    Science.gov (United States)

    Ruoff, Rodney S. (Inventor); Stankovich, Sasha (Inventor); Dikin, Dmitriy A. (Inventor); Nguyen, SonBinh T. (Inventor)

    2013-01-01

    A ceramic composite thin film or layer includes individual graphene oxide and/or electrically conductive graphene sheets dispersed in a ceramic (e.g. silica) matrix. The thin film or layer can be electrically conductive film or layer depending the amount of graphene sheets present. The composite films or layers are transparent, chemically inert and compatible with both glass and hydrophilic SiOx/silicon substrates. The composite film or layer can be produced by making a suspension of graphene oxide sheet fragments, introducing a silica-precursor or silica to the suspension to form a sol, depositing the sol on a substrate as thin film or layer, at least partially reducing the graphene oxide sheets to conductive graphene sheets, and thermally consolidating the thin film or layer to form a silica matrix in which the graphene oxide and/or graphene sheets are dispersed.

  13. Rheology of Superplastic Ceramics

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Constitutive equation of rheglogy describing a phenomenological level of superplastic deformation as functional correlation between tensor components of stress and strain rate has been analyzed for the case of superplastic ceramic flow. Rheological properties of material are taken into account by means of scalar rheological coefficients of shear and volume viscosity, which are functions of temperature, effective stress (or strain rate) and density of material.

  14. Laser Micromachining of Ceramics

    OpenAIRE

    Sciti, Diletta; Bellosi, Alida

    2011-01-01

    Laser surface processing of ceramics is an area of considerable technological importance for several structural, tribological, optical and electronic applications. The laser beam behaves as a heat source that induces a temperature rise on the surface and within the bulk of the material. Depending on laser parameters and material characteristics, lasers can be used for fabricating microholes at designated locations, for cutting, scribing, for surface modifications In this work different types ...

  15. Engineering ceramics development in BARC

    International Nuclear Information System (INIS)

    The non-nuclear ceramics research and development activities in BARC encompass the oxides carbide and nitride of light elements. The major thrust areas have been towards development of engineering ceramics like alumina, zirconia, silicon carbide and silicon nitride. The present paper summarises the research activities regarding these ceramics especially on powder synthesis and shape fabrication by injection moulding, reaction-sintering and activated sintering. The stability of silicon carbide in oxygen containing atmosphere is highlighted. (orig.)

  16. The technical ceramics (second part)

    International Nuclear Information System (INIS)

    This work deals with ceramics used in the nuclear and the automotive industries. Concerning the nuclear sector, ceramics are particularly used in reactors, in the treatment of radioactive wastes and for the storage of the ultimate wastes. Details are given about the different ceramics used. In the automobile sector, aluminium is principally used for its lightness and cordierite, basic material of catalyst supports is especially used in the automobile devices of cleansing. (O.M.)

  17. Transparent Yb:YAG ceramics

    OpenAIRE

    Hostasa, Jan; Esposito, Laura; Piancastelli, Andreana

    2011-01-01

    YAG ceramics doped with rare earth elements have been recently given a consistent attention as materials for various applications. The specific application depends on the doping element added. Addition of Yb is used for the production of active materials for solid state lasers, and YAG polycrystalline ceramics are promising materials for the replacement of single crystals, which are mostly used at present. The advantage of polycrystalline ceramics over single crystals are the lower fabricatio...

  18. Ceramic stationary gas turbine

    Energy Technology Data Exchange (ETDEWEB)

    Roode, M. van [Solar Turbines Inc., San Diego, CA (United States)

    1995-10-01

    The performance of current industrial gas turbines is limited by the temperature and strength capabilities of the metallic structural materials in the engine hot section. Because of their superior high-temperature strength and durability, ceramics can be used as structural materials for hot section components (blades, nozzles, combustor liners) in innovative designs at increased turbine firing temperatures. The benefits include the ability to increase the turbine inlet temperature (TIT) to about 1200{degrees}C ({approx}2200{degrees}F) or more with uncooled ceramics. It has been projected that fully optimized stationary gas turbines would have a {approx}20 percent gain in thermal efficiency and {approx}40 percent gain in output power in simple cycle compared to all metal-engines with air-cooled components. Annual fuel savings in cogeneration in the U.S. would be on the order of 0.2 Quad by 2010. Emissions reductions to under 10 ppmv NO{sub x} are also forecast. This paper describes the progress on a three-phase, 6-year program sponsored by the U.S. Department of Energy, Office of Industrial Technologies, to achieve significant performance improvements and emissions reductions in stationary gas turbines by replacing metallic hot section components with ceramic parts. Progress is being reported for the period September 1, 1994, through September 30, 1995.

  19. Preparation and characterization of metallic supported thin Pd-Ag membranes for hydrogen separation

    OpenAIRE

    Fernandez, Ekain; Medrano, Jose Antonio; Melendez, Jon; Parco, Maria; Viviente, J.L.; van Sint Annaland, Martin; Gallucci, Fausto; Pacheco Tanaka, David A.

    2015-01-01

    This paper reports the preparation and characterization of thin-film (4-5 µm thick) Pd-Ag metallic supported membranes for high temperature applications. Various thin film membranes have been prepared by depositing a ceramic interdiffusion barrier layer prior to the simultaneous Pd-Ag electroless plating deposition. Two deposition techniques for ceramic layers (made of zirconia and alumina) have been evaluated: atmospheric plasma spraying and dip coating of a powder suspension. Initially, the...

  20. Ion conductivity of nasicon ceramics

    International Nuclear Information System (INIS)

    The Nasiconss,Na1+XZr2SiXP3-XO12 o , X , 3, includes some of the best solid state sodium conductors known today. Compositions in the interval 1.6 , X , 2.6 show conductivities comparable to the best β double-prime-alumina ceramics. It is well known that the ion conductivity of β-alumina is strongly dependent on the texture of the ceramic. Here a similar behavior is reported for Nasicon ceramics. Ceramics of the bulk composition Na2.94Zr1.49Si2.20P0.80O10.85 were prepared by a gel method. The final ceramics consist of Nasicon crystals with x = 2.14 and a glass phase. The grain size and texture of the ceramics were controlled by varying the thermal history of the gel based raw materials and the sintering conditions. The room temperature resistivity of the resulting ceramics varies from 3.65*103 ohm cm to 1.23*103 ohm cm. Using the temperature comparison method and estimates of the area of grain boundaries in the ceramics, the resistivity of the Nasicon phase is estimated to be 225 ohm cm at 25 degrees C. B2O3- or Al2O3-doping of the glass bearing Nasicon ceramic lower the room temperature resistivity by a factor 2 to 5. The dopants do not substitute into the Nasicon phase in substantial amounts

  1. Hydrogen Purification Using Natural Zeolite Membranes

    Science.gov (United States)

    DelValle, William

    2003-01-01

    The School of Science at Universidad del Turabo (UT) have a long-lasting investigation plan to study the hydrogen cleaning and purification technologies. We proposed a research project for the synthesis, phase analysis and porosity characterization of zeolite based ceramic perm-selective membranes for hydrogen cleaning to support NASA's commitment to achieving a broad-based research capability focusing on aerospace-related issues. The present study will focus on technology transfer by utilizing inorganic membranes for production of ultra-clean hydrogen for application in combustion. We tested three different natural zeolite membranes (different particle size at different temperatures and time of exposure). Our results show that the membranes exposured at 900 C for 1Hr has the most higher permeation capacity, indicated that our zeolite membranes has the capacity to permeate hydrogen.

  2. Liners for ion transport membrane systems

    Science.gov (United States)

    Carolan, Michael Francis; Miller, Christopher Francis

    2010-08-10

    Ion transport membrane system comprising (a) a pressure vessel comprising an interior, an exterior, an inlet, an inlet conduit, an outlet, and an outlet conduit; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region, wherein the inlet and the outlet of the pressure vessel are in flow communication with exterior regions of the membrane modules; (c) a gas manifold having an interior surface wherein the gas manifold is in flow communication with the interior region of each of the planar ion transport membrane modules and with the exterior of the pressure vessel; and (d) a liner disposed within any of the inlet conduit, the outlet conduit, and the interior surface of the gas manifold.

  3. Membrane Processes.

    Science.gov (United States)

    Pellegrin, Marie-Laure; Burbano, Marie S; Sadler, Mary E; Diamond, Jason; Baker, Simon; Greiner, Anthony D; Arabi, Sara; Wong, Joseph; Doody, Alexandra; Padhye, Lokesh P; Sears, Keith; Kistenmacher, Peter; Kent, Fraser; Tootchi, Leila; Aguinaldo, Jorge; Saddredini, Sara; Schilling, Bill; Min, Kyungnan; McCandless, Robert; Danker, Bryce; Gamage, Neranga P; Wang, Sunny; Aerts, Peter

    2016-10-01

    This review, for literature published in 2015, contains information related to membrane processes for municipal and industrial applications. This review is a subsection of the Treatment Systems section of the annual Water Environment Federation literature review and covers the following topics: pretreatment, membrane bioreactor (MBR) configuration, design, nutrient removal, operation, industrial treatment, anaerobic membrane systems, reuse, microconstituents removal, membrane technology advances, membrane fouling, and modeling. Other sub-sections of the Treatment Systems section that might relate to this literature review include: Biological Fixed-Film Systems, Activated Sludge and Other Aerobic Suspended Culture Processes, Anaerobic Processes, Water Reclamation and Reuse. The following sections might also have related information on membrane processes: Industrial Wastes, Hazardous Wastes, and Fate and Effects of Pollutants. PMID:27620084

  4. Membrane Processes.

    Science.gov (United States)

    Pellegrin, Marie-Laure; Sadler, Mary E; Greiner, Anthony D; Aguinaldo, Jorge; Min, Kyungnan; Zhang, Kai; Arabi, Sara; Burbano, Marie S; Kent, Fraser; Shoaf, Robert

    2015-10-01

    This review, for literature published in 2014, contains information related to membrane processes for municipal and industrial applications. This review is a subsection of the Treatment Systems section of the annual Water Environment Federation literature review and covers the following topics: pretreatment, membrane bioreactor (MBR) configuration, design, nutrient removal, operation, industrial treatment, fixed film and anaerobic membrane systems, reuse, microconstituents removal, membrane technology advances, membrane fouling, and modeling. Other sub-sections of the Treatment Systems section that might relate to this literature review include: Biological Fixed-Film Systems, Activated Sludge and Other Aerobic Suspended Culture Processes, Anaerobic Processes, Water Reclamation and Reuse. The following sections might also have related information on membrane processes: Industrial Wastes, Hazardous Wastes, and Fate and Effects of Pollutants. PMID:26420079

  5. Geo-Enabled, Mobile Services

    DEFF Research Database (Denmark)

    Jensen, Christian Søndergaard

    2006-01-01

    We are witnessing the emergence of a global infrastructure that enables the widespread deployment of geo-enabled, mobile services in practice. At the same time, the research community has also paid increasing attention to data management aspects of mobile services. This paper offers me an...

  6. Improved Tensile Test for Ceramics

    Science.gov (United States)

    Osiecki, R. A.

    1982-01-01

    For almost-nondestructive tensile testing of ceramics, steel rod is bonded to sample of ceramic. Assembly is then pulled apart in conventional tensile-test machine. Test destroys only shallow surface layer which can be machined away making specimen ready for other uses. Method should be useful as manufacturing inspection procedure for low-strength brittle materials.

  7. Ceramics in nuclear waste management

    Energy Technology Data Exchange (ETDEWEB)

    Chikalla, T D; Mendel, J E [eds.

    1979-05-01

    Seventy-three papers are included, arranged under the following section headings: national programs for the disposal of radioactive wastes, waste from stability and characterization, glass processing, ceramic processing, ceramic and glass processing, leaching of waste materials, properties of nuclear waste forms, and immobilization of special radioactive wastes. Separate abstracts were prepared for all the papers. (DLC)

  8. Lightweight high performance ceramic material

    Science.gov (United States)

    Nunn, Stephen D [Knoxville, TN

    2008-09-02

    A sintered ceramic composition includes at least 50 wt. % boron carbide and at least 0.01 wt. % of at least one element selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy Ho, Er, Tm, Yb, and Lu, the sintered ceramic composition being characterized by a density of at least 90% of theoretical density.

  9. Estudo do processamento por microfiltração de soluções aquosas de pectina em membranas cerâmicas = Study of aqueous pectin solutions microfiltration process by ceramic membrane

    Directory of Open Access Journals (Sweden)

    Vítor Renan da Silva

    2011-04-01

    Full Text Available Neste trabalho foram avaliados os efeitos da pressao, a eficiencia de separacao e os efeitos resistivos na microfiltracao de solucoes aquosas de pectina. O valor do fluxo de permeado estabilizado foi determinado para solucoes com concentracoes de 1,0 e 2,0 g L-1 submetidas a pressoes de 0,4; 0,8; 1,2 e 1,6 bar. Um delineamento fatorial completo com dois niveis foi realizado para se avaliar os efeitos da pressao, temperatura e concentracao nas resistencias doprocesso. Os ensaios foram conduzidos em um sistema de microfiltracao tangencial com membranas multitubulares com tamanho nominal de poro de 0,44 ƒÝm e vazao de alimentacao de 1,0 m3 h-1. Determinaram-se os coeficientes de retencao de pectina e as resistencias seguindo omodelo das resistencias em serie. Os maiores fluxos de permeados para solucoes com 1,0 e 2,0 g L-1 foram observados, respectivamente, a pressao de 1,2 e 0,8 bar, enquanto os menores fluxos foram observados a 1,6 bar. O fluxo de permeado e a resistencia por polarizacao elevam-se com o aumento da temperatura e da concentracao, respectivamente. O coeficiente de retencao minimo observado foi de 93,4 % e a resistencia mais significativa foi a do fouling. A maior resistencia foi de 4,13 x 109 m2 kg-1 para temperatura de 30¢XC e concentracao de 2,0 g L-1. In this work, pressure effects, separation efficiency and resistive effects of microfiltration of pectin solution were investigated. Stabilized permeate flux values were obtained for solutions concentrations of 1.0 and 2.0 g L-1 under different pressure conditions of 0.4, 0.8, 1.2 and 1.6 bar. A full factorial design with two levels was applied to evaluate the effects of the pressure, temperature and concentration in the process resistances. The experiments were performed in a crossflow microfiltration system with multitubular membrane with nominal pore size of 0.44 ƒÝm and feed flow of 1.0 m3 h-1. Pectin retention coefficients and process resistances were obtained following

  10. Hydrogen Separation Membranes for Vision 21 Fossil Fuel Plants

    Energy Technology Data Exchange (ETDEWEB)

    Roark, Shane E.; Mackay, Richard; Sammells, Anthony F.

    2001-11-06

    Eltron Research and team members CoorsTek, McDermott Technology, Sued Chemie, Argonne National Laboratory, and Oak Ridge National Laboratory are developing an environmentally benign, inexpensive, and efficient method for separating hydrogen from gas mixtures produced during industrial processes, such as coal gasification. This objective is being pursued using dense membranes based in part on Eltron-patented ceramic materials with a demonstrated ability for proton and electron conduction. The technical goals are being addressed by modifying single-phase and composite membrane composition and microstructure to maximize proton and electron conductivity without loss of material stability. Ultimately, these materials must enable hydrogen separation at practical rates under ambient and high-pressure conditions, without deactivation in the presence of feedstream components such as carbon dioxide, water, and sulfur. This project was motivated by the Department of Energy (DOE) National Energy Technology Laboratory (NETL) Vision 21 initiative which seeks to economically eliminate environmental concerns associated with the use of fossil fuels. The proposed technology addresses the DOE Vision 21 initiative in two ways. First, this process offers a relatively inexpensive solution for pure hydrogen separation that can be easily incorporated into Vision 21 fossil fuel plants. Second, this process could reduce the cost of hydrogen, which is a clean burning fuel under increasing demand as supporting technologies are developed for hydrogen utilization and storage. Additional motivation for this project arises from the potential of this technology for other applications. By appropriately changing the catalysts coupled with the membrane, essentially the same system can be used to facilitate alkane dehydrogenation and coupling, aromatics processing, and hydrogen sulfide decomposition.

  11. Low thermal expansion glass ceramics

    CERN Document Server

    1995-01-01

    This book is one of a series reporting on international research and development activities conducted by the Schott group of companies With the series, Schott aims to provide an overview of its activities for scientists, engineers, and managers from all branches of industry worldwide where glasses and glass ceramics are of interest Each volume begins with a chapter providing a general idea of the current problems, results, and trends relating to the subjects treated This volume describes the fundamental principles, the manufacturing process, and applications of low thermal expansion glass ceramics The composition, structure, and stability of polycrystalline materials having a low thermal expansion are described, and it is shown how low thermal expansion glass ceramics can be manufactured from appropriately chosen glass compositions Examples illustrate the formation of this type of glass ceramic by utilizing normal production processes together with controlled crystallization Thus glass ceramics with thermal c...

  12. Glass, Ceramics, and Composites

    International Nuclear Information System (INIS)

    Many studies of plutonium in glass and ceramics have taken place in the thirty years covered by this book. These studies have led to a substantial understanding, arising from fundamental research of actinides in solids and research and development in three technical fields: immobilization of the high level wastes (HLW) from commercial nuclear power plants and processing of nuclear weapons materials, environmental restoration in the nuclear weapons complex and, most recently, the immobilization of weapons-grade plutonium as a result of disarmament activities

  13. Development of ceramic composites from mixture of alumina and ceramic precursor polymer poly (silsesquioxane))

    International Nuclear Information System (INIS)

    Processing of ceramics materials, by polymer precursors pyrolysis, has been intensively researched over the past decades, due to advantages that this path provides, such as: lower temperature process compared to conventional techniques; structure control at molecular level; synthesis possibility of a wide range of ceramic compounds; obtaining parts with dimensions of the final product etc. The active filler controlled polymer pyrolysis (AFCOP) process, enables the synthesis of ceramic composites, by reaction between added filler (oxides, metals, intermetallic etc.) and solid and gaseous products, from polymer decomposition. In this study, based on this process, samples of alumina, with addition of 10 and 20 mass% of poly silsesquioxane polymer precursor, were manufactured. These samples were pyrolyzed at 900 degree C and thermal treated at temperatures of 1100, 1300 and 1500 degree C. The samples were characterized for bulk density, porosity and hardness, after each stage of thermal treatment. Structural transformations were analyzed by X-ray diffraction, scanning electron microscopy and infrared spectroscopy. Samples treated until 1300 degree C resulted in composites of alumina and silicon oxycarbide, while those treated at 1500 degree C, formed composites of mullite and alumina. The samples with 20% of polymer added started to density around 800 degree C and high retraction rate was observed at 1400 degree C. (author)

  14. Estimation of the heat of reaction in traditional ceramic compositions

    OpenAIRE

    Ferrer, S.; Mezquita, Ana; Gómez Tena, María Pilar; Machí, Cristina; Monfort Gimeno, Eliseo

    2015-01-01

    Most energy studies on the traditional ceramic manufacturing process focus on the firing stage because this is the process stage that consumes the greatest amount of thermal energy. At present in Europe, using typical technologies, about 50% of the energy input in the firing stage is still lost through the kiln stacks. A key issue in energy studies is the accurate determination of the energy efficiency of the process, an issue that may become crucial in coming years to enable the energy manag...

  15. Failure of Ceramic Composites in Non-Uniform Stress Fields

    OpenAIRE

    Rajan, Varun

    2014-01-01

    Continuous-fiber ceramic matrix composites (CMCs) are of interest as hot-section components in gas turbine engines due to their refractoriness and low density relative to metallic alloys. In service, CMCs will be subjected to spatially inhomogeneous temperature and stress fields. Robust tools that enable prediction of deformation and fracture under these conditions are therefore required for component design and analysis. Such tools are presently lacking. The present work helps to address thi...

  16. Characterization of Polymeric Nanofiltration Membranes

    Directory of Open Access Journals (Sweden)

    Simoncic, B.

    2007-11-01

    Full Text Available As membrane processes are increasingly used in industrial applications, there is a growing interest in methods of membrane characterization. Traditional membrane characteristics, such as cut-off value and pore size distribution, are being supplemented by membrane surface characteristics, such as charge density or zeta potential and hydrophobicity. This study, therefore, characterizes the three different polymeric membranes used (NFT-50, DL and DK. The molecular mass cut-off (MMCO value was determined using a set of reference solutes within the molecular range 150-600 Da, whereas streaming potential measurements enabled quantification of the surface charge characteristics. Hydrophobicity was studied using contact angle measurements. The results indicated that even though all three membranes had very similar layer compositions which consisted of poly(piperazneamide, as top layers they showed different values of measured quantitive. The NFT-50 membrane had the lowest MMCO value and the most hydrophilic membrane surface, followed by DK and DL. Membrane fouling as measured by flux reduction was determined by streaming potential measurements and accompanied by a positive change in zeta potential.

  17. High-temperature corrosion resistance of ceramics and ceramic coatings

    Energy Technology Data Exchange (ETDEWEB)

    Tortorelli, P.F.

    1996-06-01

    Ceramics and ceramic composites offer the potential to operate fossil energy systems at the higher temperatures necessary for improved energy efficiency and better environmental control. However, because many fossil fuel-derived processes contain sulfur, chlorine, and carbon, as well as oxygen, degradation from high-temperature corrosion and environmental effects arising from reactions of solids with gases and condensable products is a common life-determining factor in operating systems. Ceramic-based products are not immune to such degradation; adequate corrosion resistance must be assured to exploit the technical and economic potential of such materials. This is normally accomplished by using stable, sound oxides that exist in their bulk form, that naturally grow as surface layers upon exposure to an oxidizing environment, or that are deposited as a coating on a susceptible material. It is therefore important to examine the critical issues with respect to more environmental stability of ceramics that have the potential to be corrosion resistant in particular fossil environments. Key aspects include not only chemical compatibility, but the influence of the environment on the mechanical behavior of the ceramic materials. In addition, for coatings, the mechanical reliability of the ceramic is a key issue in that an otherwise corrosion-resistant surface layer must remain sound and adherent in order to provide protection to the underlying substrate. The purpose of this work is to support the development of advanced ceramics and ceramic composites for applications in fossil environments by examining critical issues related to high-temperature corrosion resistance. More specifically, the overall objective of this task is to examine the chemical compatibility and reliability of potentially corrosion-resistant ceramics being developed as protective overcoats and/or structural materials as parts of other work elements funded by the AR&TD Program.

  18. Fast Measurements Of Thermal Diffusivities Of Ceramics

    Science.gov (United States)

    Smith, Marnell; Goldstein, Howard E.

    1988-01-01

    Temperature rises of samples compared with reference sample. Apparatus quickly measures thermal diffusivities of ceramics at high temperatures. Produces data on relative thermal diffusivities of as many as six ceramic specimens per hour. Thermal-diffusivity tester makes it easy to determine thermal diffusivities of ceramics. Pronounced effects of processing parameters on thermal properties of ceramics evaluated quickly.

  19. Removing Pathogens Using Nano-Ceramic-Fiber Filters

    Science.gov (United States)

    Tepper, Frederick; Kaledin, Leonid

    2005-01-01

    A nano-aluminum-oxide fiber of only 2 nanometers in diameter was used to develop a ceramic-fiber filter. The fibers are electropositive and, when formulated into a filter material (NanoCeram(TradeMark)), would attract electro-negative particles such as bacteria and viruses. The ability to detect and then remove viruses as well as bacteria is of concern in space cabins since they may be carried onboard by space crews. Moreover, an improved filter was desired that would polish the effluent from condensed moisture and wastewater, producing potable drinking water. A laboratory- size filter was developed that was capable of removing greater than 99.9999 percent of bacteria and virus. Such a removal was achieved at flow rates hundreds of times greater than those through ultraporous membranes that remove particles by sieving. Because the pore size of the new filter was rather large as compared to ultraporous membranes, it was found to be more resistant to clogging. Additionally, a full-size cartridge is being developed that is capable of serving a full space crew. During this ongoing effort, research demonstrated that the filter media was a very efficient adsorbent for DNA (deoxyribonucleic acid), RNA (ribonucleic acid), and endotoxins. Since the adsorption is based on the charge of the macromolecules, there is also a potential for separating proteins and other particulates on the basis of their charge differences. The separation of specific proteins is a major new thrust of biotechnology. The principal application of NanoCeram filters is based on their ability to remove viruses from water. The removal of more than 99.9999 percent of viruses was achieved by a NanoCeram polishing filter added to the effluent of an existing filtration device. NanoCeram is commercially available in laboratory-size filter discs and in the form of a syringe filter. The unique characteristic of the filter can be demonstrated by its ability to remove particulate dyes such as Metanyl yellow. Its

  20. Preparation and characterization of resin-derived carbon foams reinforced by hollow ceramic microspheres

    International Nuclear Information System (INIS)

    Carbon foam materials were prepared with phenolic resole resin as precursor and hollow ceramic microspheres as reinforcement. The resultant carbon foams had a bulk density of between 0.22 and 0.27 g/cm3. Analysis of scanning electron micrographs indicated that the cells were mainly open with incomplete cell membranes, and the hollow ceramic microspheres were located in the junctions. Compression test results showed that the carbon foams with 1 wt% hollow ceramic microspheres exhibited the highest compressive strength (7.76 MPa). Thermal conductivity measurements revealed that the introduction of hollow ceramic microspheres improved the thermal insulating property. The thermal conductivity of carbon foams ranged from 0.11 to 0.25 W m-1 K-1 at room temperature, which makes carbon foams a prime choice for thermal insulation.

  1. Transport proteins of the plant plasma membrane

    Science.gov (United States)

    Assmann, S. M.; Haubrick, L. L.; Evans, M. L. (Principal Investigator)

    1996-01-01

    Recently developed molecular and genetic approaches have enabled the identification and functional characterization of novel genes encoding ion channels, ion carriers, and water channels of the plant plasma membrane.

  2. Taxonomy Enabled Discovery (TED) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposal addresses the NASA's need to enable scientific discovery and the topic's requirements for: processing large volumes of data, commonly available on the...

  3. Corrosion Issues for Ceramics in Gas Turbines

    Science.gov (United States)

    Jacobson, Nathan S.; Fox, Dennis S.; Smialek, James L.; Opila, Elizabeth J.; Tortorelli, Peter F.; More, Karren L.; Nickel, Klaus G.; Hirata, Takehiko; Yoshida, Makoto; Yuri, Isao

    2000-01-01

    The requirements for hot-gas-path materials in gas turbine engines are demanding. These materials must maintain high strength and creep resistance in a particularly aggressive environment. A typical gas turbine environment involves high temperatures, rapid gas flow rates, high pressures, and a complex mixture of aggressive gases. Figure 26.1 illustrates the requirements for components of an aircraft engine and critical issues [1]. Currently, heat engines are constructed of metal alloys, which meet these requirements within strict temperature limits. In order to extend these temperature limits, ceramic materials have been considered as potential engine materials, due to their high melting points and stability at high temperatures. These materials include oxides, carbides, borides, and nitrides. Interest in using these materials in engines appears to have begun in the 1940s with BeO-based porcelains [2]. During the 1950s, the efforts shifted to cermets. These were carbide-based materials intended to exploit the best properties of metals and ceramics. During the 1960s and 1970s, the silicon-based ceramics silicon carbide (SiC) and silicon nitride (Si3N4) were extensively developed. Although the desirable high-temperature properties of SiC and Si3N4 had long been known, consolidation of powders into component-sized bodies required the development of a series of specialized processing routes [3]. For SiC, the major consolidation routes are reaction bonding, hot-pressing, and sintering. The use of boron and carbon as additives which enable sintering was a particularly noteworthy advance [4]. For Si3N4 the major consolidation routes are reaction bonding and hot pressing [5]. Reaction-bonding involves nitridation of silicon powder. Hot pressing involves addition of various refractory oxides, such as magnesia (MgO), alumina (Al2O3), and yttria (y2O3). Variations on these processes include a number of routes including Hot Isostatic Pressing (HIP), gas-pressure sintering

  4. Solidification analysis of AMMCs with ceramic particles

    Directory of Open Access Journals (Sweden)

    J. Sleziona

    2007-07-01

    Full Text Available Purpose: In the research work the result of the reinforcement displacement and solidification analysis for aluminiumcast composites with ceramic particles have been presented. The results of research on the solidification procesare compared for the applied aluminium matrix alloy (AlSi12CuNiMg2, for composites containing glass carboparticles (Cg and heterophase reinforcement (mixture of silicon carbide (SiC + glass carbon particles (Cg.Design/methodology/approach: The course of the solidification process was recorded by means of a systemwhich enabled continuous control and measurement of the metal temperature during solidification of the compositsuspension. The system was equipped with a thermoelectric cup core QC4080, with an incorporated thermocouple oK type (NiCr-Ni. The application of disposable thermoelectric cup cores of identical heat abstraction coefficient anknown, standardized dimensions, ensured identical conditions and rate of heat abstraction during the cooling of thcastings. The structure analysis for composite casts was performed by means of optical and scanning microscopy.Findings: The research has shown, that ceramic particles have an influence on temperature change and the timof aluminium matrix alloy solidification. The changes results, first of all, from disparate physical properties othe glassy carbon particles and silicon carbide particles used (thermal conductivity, mass density, compared taluminium matrix alloy.Practical implications: Ceramic particles decrease shrinkage of the casting and change the nature of itcrystallization.Originality/value: Employment of glass carbon particles for matrix reinforcement allows to get flotation in thaluminium alloy. Employment of heterophase reinforcement (glass carbon and silicon carbide particles allows tget segregation of particles: flotation as well as sedimentation in the matrix, which results in the occurrence of layered structure.

  5. Microfiltration of distillery stillage: Influence of membrane pore size

    Directory of Open Access Journals (Sweden)

    Vasić Vesna M.

    2012-01-01

    Full Text Available Stillage is one of the most polluted waste products of the food industry. Beside large volume, the stillage contains high amount of suspended solids, high values of chemical oxygen demand and biological oxygen demand, so it should not be discharged in the nature before previous purification. In this work, three ceramic membranes for microfiltration with different pore sizes were tested for stillage purification in order to find the most suitable membrane for the filtration process. Ceramic membranes with a nominal pore size of 200 nm, 450 nm and 800 nm were used for filtration. The influence of pore size on permeate flux and removal efficiency was investigated. A membrane with the pore size of 200 nm showed the best filtration performance so it was chosen for the microfiltration process.

  6. ENHANCEMENT OF EQUILIBRIUMSHIFT IN DEHYDROGENATION REACTIONS USING A NOVEL MEMBRANE REACTOR; FINAL

    International Nuclear Information System (INIS)

    With the advances in new inorganic materials and processing techniques, there has been renewed interest in exploiting the benefits of membranes in many industrial applications. Inorganic and composite membranes are being considered as potential candidates for use in membrane-reactor configuration for effectively increasing reaction rate, selectivity and yield of equilibrium limited reactions. To investigate the usefulness of a palladium-ceramic composite membrane in a membrane reactor-separator configuration, we investigated the dehydrogenation of cyclohexane by equilibrium shift. A two-dimensional pseudo-homogeneous reactor model was developed to study the dehydrogenation of cyclohexane by equilibrium shift in a tubular membrane reactor. Radial diffusion was considered to account for the concentration gradient in the radial direction due to permeation through the membrane. For a dehydrogenation reaction, the feed stream to the reaction side contained cyclohexane and argon, while the separation side used argon as the sweep gas. Equilibrium conversion for dehydrogenation of cyclohexane is 18.7%. The present study showed that 100% conversion could be achieved by equilibrium shift using Pd-ceramic membrane reactor. For a feed containing cyclohexane and argon of 1.64 x 10(sup -6) and 1.0 x 10(sup -3) mol/s, over 98% conversion could be readily achieved. The dehydrogenation of cyclohexane was also experimentally investigated in a palladium-ceramic membrane reactor. The Pd-ceramic membrane was fabricated by electroless deposition of palladium on ceramic substrate. The performance of Pd-ceramic membrane was compared with a commercially available hydrogen-selective ceramic membrane. From limited experimental data it was observed that by appropriate choice of feed flow rate and sweep gas rate, the conversion of cyclohexane to benzene and hydrogen can increased to 56% at atmospheric pressure and 200 C in a Pd-ceramic membrane reactor. In the commercial ceramic membrane

  7. Gas Permeation Characteristics across Nano-Porous Inorganic Membranes

    Directory of Open Access Journals (Sweden)

    M.R Othman, H. Mukhtar

    2012-10-01

    Full Text Available An overview of parameters affecting gas permeation in inorganic membranes is presented. These factors include membrane physical characteristics, operational parameters and gas molecular characteristics. The membrane physical characteristics include membrane materials and surface area, porosity, pore size and pore size distribution and membrane morphology. The operational parameters include feed flow rate and concentration, stage cut, temperature and pressure. The gas molecular characteristics include gas molecular weight, diameter, critical temperature, critical pressure, Lennard-Jones parameters and diffusion volumes. The current techniques of material characterization may require complementary method in describing microscopic heterogeneity of the porous ceramic media. The method to be incorporated in the future will be to apply a stochastic model and/or fractal dimension. Keywords: Inorganic membrane, surface adsorption, Knudsen diffusion, Micro-porous membrane, permeation, gas separation.

  8. Thermoluminescence dating of Brazilian indigenous ceramics.

    Science.gov (United States)

    Farias, T M B; Gennari, R F; Etchevarne, C; Watanabe, S

    2009-08-01

    Two indigenous ceramics fragments, one from Lagoa Queimada (LQ) and another from Barra dos Negros (BN), both sites located on Bahia state (Brazil), were dated by thermoluminescence (TL) method. Each fragment was physically prepared and divided into two fractions, one was used for TL measurement and the other for annual dose determination. The TL fraction was chemically treated, divided in sub samples and irradiated with several doses. The plot extrapolation from TL intensities as function of radiation dose enabled the determination of the accumulated dose (D(ac)), 3.99 Gy and 1.88 Gy for LQ and BN, respectively. The annual dose was obtained through the uranium, thorium and potassium determination by ICP-MS. The annual doses (D(an)) obtained were 2.86 and 2.26 mGy/year. The estimated ages were approximately 1375 and 709 y for BN and LQ ceramics, respectively. The ages agreed with the archaeologists' estimation for the Aratu and Tupi tradition periods, respectively. PMID:19617598

  9. Thermoluminescence dating of Brazilian indigenous ceramics

    International Nuclear Information System (INIS)

    Two indigenous ceramics fragments, one from Lagoa Queimada (LQ) and another from Barra dos Negros (BN), both sites located on Bahia state (Brazil), were dated by thermoluminescence (TL) method. Each fragment was physically prepared and divided into two fractions, one was used for TL measurement and the other for annual dose determination. The TL fraction was chemically treated, divided in sub samples and irradiated with several doses. The plot extrapolation from TL intensities as function of radiation dose enabled the determination of the accumulated dose (Dac), 3.99 Gy and 1.88 Gy for LQ and BN, respectively. The annual dose was obtained through the uranium, thorium and potassium determination by ICP-MS. The annual doses (D an) obtained were 2.86 and 2.26 mGy/year. The estimated ages were ∼1375 and 709 y for BN and LQ ceramics, respectively. The ages agreed with the archaeologists' estimation for the Aratu and Tupi tradition periods, respectively. (authors)

  10. Wear prediction of ceramic-on-ceramic hip artificial joints

    OpenAIRE

    Askari, E; Flores, Paulo; Dabirrahmani, D.; Appleyard, R.

    2015-01-01

    Wear can influence the lifetime and performance of implants and has been found to be a key factor in primary failure of artificial hip joints. The present study aims to present a spatial multibody dynamic model to predict wear in ceramic-on-ceramic hip implants. The problem was formulated by developing a spatial multibody dynamic model of a hip prosthesis taking three-dimensional physiological loading and motion of the human body into account. Then, the Archard wear model was inte...

  11. Insight into Enabling Adaptive Management

    Directory of Open Access Journals (Sweden)

    Lorne A. Greig

    2013-09-01

    Full Text Available The U.S. National Commission on Science for Sustainable Forestry recognized a need for effective adaptive management to support management for biological diversity. However, difficulties in implementing adaptive management in the U.S. Northwest Forest Plan led the Commission to wonder if comparisons across multiple adaptive management trials in the forest sector could provide insight into the factors that serve to enable or inhibit adaptive management. This comparison and the resulting discussions among a group of seasoned practitioners, with adaptive management experience at a variety of scales and levels of complexity, led to insights into a hierarchy of ten factors that can serve to either enable or inhibit implementation. Doing high quality adaptive management is about doing good science to enable learning from management experience. Enabling adaptive management though is about working with people to understand their concerns, to develop a common understanding and an environment of trust that allows adaptive management to proceed. Careful attention to enabling factors is critical to fulfilling the promise of adaptive management.

  12. Ceramics for fusion devices

    International Nuclear Information System (INIS)

    Ceramics are required for a number of applications in fusion devices, among the most critical of which are magnetic coil insulators, windows for RF heating systems, and structural uses. Radiation effects dominate consideration of candidate materials, although good pre-irradiation properties are a requisite. Materials and components can be optimized by careful control of chemical and microstructural content, and application of brittle material design and testing techniques. Future directions for research and development should include further extension of the data base in the areas of electrical, structural, and thermal properties; establishment of a fission neutron/fusion neutron correlation including transmutation gas effects; and development of new materials tailored to meet the specific needs of fusion reactors

  13. Ceramic Cerami Turbine Nozzle

    Science.gov (United States)

    Boyd, Gary L.

    1997-04-01

    A turbine nozzle vane assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and being attached to conventional metallic components. The metallic components having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine nozzle vane assembly. The turbine nozzle vane assembly includes an outer shroud and an inner shroud having a plurality of horizontally segmented vanes therebetween being positioned by a connecting member positioning segmented vanes in functional relationship one to another. The turbine nozzle vane assembly provides an economical, reliable and effective ceramic component having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the other component.

  14. Ceramic turbine nozzle

    Science.gov (United States)

    Shaffer, James E.; Norton, Paul F.

    1996-01-01

    A turbine nozzle and shroud assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and being attached to conventional metallic components. The metallic components having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine nozzle vane assembly. The turbine nozzle vane assembly includes a plurality of segmented vane defining a first vane segment and a second vane segment. Each of the first and second vane segments having a vertical portion. Each of the first vane segments and the second vane segments being positioned in functional relationship one to another within a recess formed within an outer shroud and an inner shroud. The turbine nozzle and shroud assembly provides an economical, reliable and effective ceramic component having a preestablished rate of thermal expansion being less than the preestablished rate of thermal expansion of the other component.

  15. Creep in electronic ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Routbort, J. L.; Goretta, K. C.; Arellano-Lopez, A. R.

    2000-04-27

    High-temperature creep measurements combined with microstructural investigations can be used to elucidate deformation mechanisms that can be related to the diffusion kinetics and defect chemistry of the minority species. This paper will review the theoretical basis for this correlation and illustrate it with examples from some important electronic ceramics having a perovskite structure. Recent results on BaTiO{sub 3}, (La{sub 1{minus}x}Sr){sub 1{minus}y}MnO{sub 3+{delta}}, YBa{sub 2}Cu{sub 3}O{sub x}, Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x}, (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} and Sr(Fe,Co){sub 1.5}O{sub x} will be presented.

  16. Two-Step Reactive Aid Sintering of BaZr0.8Y0.2O3- δ Proton-Conducting Ceramics

    Science.gov (United States)

    Wang, Siwei; Chen, Yan; Zhang, Lingling; Ren, Cong; Chen, Fanglin; Brinkman, Kyle S.

    2015-12-01

    Ceramic-based proton conductors enable high-temperature hydrogen economy applications such as hydrogen separation membranes, fuel cells, and steam electrolyzers. BaZr0.8Y0.2O3- δ (BZY) proton-conducting oxide possesses the highest level of proton conductivity reported to date, but poor sinterability hinders its widespread utilization. In this paper, we report a two-step reactive aid sintering (TRAS) method involving the introduction of BaCO3 and B2O3-Li2O for the preparation of dense BZY ceramics sintered at 1500°C. The resulting BZY samples showed a pure perovskite structure with a dramatic increase in the relative density to 91.5%. In addition, the shrinkage during sintering was improved to 19.3% by a TRAS method as compared to 2.6% by the conventional solid date reaction method. The bulk conductivity was improved due to enhanced densification, while the grain boundary conductivity decreased due to the blocking behavior of the sintering aid resulting in a decrease in the total conductivity of the samples.

  17. FILTER COMPONENT ASSESSMENT--CERAMIC CANDLES--

    Energy Technology Data Exchange (ETDEWEB)

    M.A. Alvin

    2004-04-23

    Efforts at Siemens Westinghouse Power Corporation (SWPC) have been focused on development of hot gas filter systems as an enabling technology for advanced coal and biomass-based gas turbine power generation applications. SWPC has been actively involved in the development of advanced filter materials and component configuration, has participated in numerous surveillance programs characterizing the material properties and microstructure of field tested filter elements, and has undertaken extended, accelerated filter life testing programs. This report summarizes the results of SWPC's filter component assessment efforts, identifying the performance and stability of porous monolithic, fiber reinforced, and filament wound ceramic hot gas candle filters, potentially for {ge}3 years of viable pressurized fluidized-bed combustion (PFBC) service operating life.

  18. Dynamic hyperfiltration membranes for high-temperature spacecraft wash water recycle

    Science.gov (United States)

    Gaddis, J. L.; Brandon, C. A.

    1978-01-01

    The effect of operating parameters on the performance of the hyperfiltration membrane when operating on washwater was examined. The parameters were pressure, temperature, velocity, and concentration. Data taken included rejections of organic materials, ammonia, urea, and an assortment of ions. The membrane used was a dual layer, polyacrylic acid over zirconium oxide, deposited in situ on a porcelain ceramic substrate.

  19. Inorganic glass ceramic slip rings

    Science.gov (United States)

    Glossbrenner, E. W.; Cole, S. R.

    1972-01-01

    Prototypes of slip rings have been fabricated from ceramic glass, a material which is highly resistant to deterioration due to high temperature. Slip ring assemblies were not structurally damaged by mechanical tests and performed statisfactorily for 200 hours.

  20. Low Thermal Expansion Glass Ceramics

    CERN Document Server

    Bach, Hans

    2005-01-01

    This book appears in the authoritative series reporting the international research and development activities conducted by the Schott group of companies. This series provides an overview of Schott's activities for scientists, engineers, and managers from all branches of industry worldwide in which glasses and glass ceramics are of interest. Each volume begins with a chapter providing a general idea of the current problems, results, and trends relating to the subjects treated. This new extended edition describes the fundamental principles, the manufacturing process, and applications of low thermal expansion glass ceramics. The composition, structure, and stability of polycrystalline materials having a low thermal expansion are described, and it is shown how low thermal expansion glass ceramics can be manufactured from appropriately chosen glass compositions. Examples illustrate the formation of this type of glass ceramic by utilizing normal production processes together with controlled crystallization. Thus g...

  1. The ceramic gas electron multiplier

    Energy Technology Data Exchange (ETDEWEB)

    Tosson, Amir; Fleck, Ivor [Siegen University, Siegen (Germany); Collaboration: LCTPC-Deutschland-Collaboration

    2015-07-01

    The Gas Electron Multiplier (GEM) has been proven to fulfill the demands of high energy physics experiments. Effective gain and resistance to the electrical sparks are significant issues to be investigated. A new type of GEM, made out of ceramic, has been produced and results from measurements with this type of GEM are presented. Advantages of ceramic material are its very good stability versus change in temperature and its electrical properties. Using Ar-CO{sub 2}(80-20 %) gas mixture and a X-ray source, the gain of the ceramic GEMs is measured and compared with the one for CERN GEMs. These results assure the possibility of using the ceramic GEMs for high-luminosity experiments.

  2. Ammonia recycling enables sustainable operation of bioelectrochemical systems.

    Science.gov (United States)

    Cheng, Ka Yu; Kaksonen, Anna H; Cord-Ruwisch, Ralf

    2013-09-01

    Ammonium (NH4(+)) migration across a cation exchange membrane is commonly observed during the operation of bioelectrochemical systems (BES). This often leads to anolyte acidification (pH 10) from the cathodic headspace to the acidified anolyte. Results indicated that current (110 mA or 688 Am(-3) net anodic chamber volume) was sustained as long as the NH3 recycling path was enabled, facilitating continuous anolyte neutralization with the recycled NH3. Since the microbial current enabled NH4(+) migration against a strong concentration gradient (~10-fold), a novel way of ammonia recovery from wastewaters could be envisaged. PMID:23774293

  3. Antibacterial and mechanical properties of honeycomb ceramic materials incorporated with silver and zinc

    International Nuclear Information System (INIS)

    Highlights: • Novel application of honeycomb ceramic carrier for environmentally benign processes. • Honeycomb ceramic have antibacterial properties by doping with silver and zinc. • The foundation of honeycomb ceramic to promote the application in various fields. • Honeycomb ceramic microstructure and characterization by XRD and SEM micro-analysis. - Abstract: The antibacterial and mechanical properties of heat-resistant honeycomb ceramic materials produced from red mud industrial waste and doped with Zn and Ag are determined. Excellent antibacterial effects against Escherichia coli are obtained by the plate counting and vibration methods. When 5% and 6% Zn are added to the honeycombs doped with 0.3% Ag, the antibacterial rates reach 98.9% and 99.5%, respectively. The mechanical properties are evaluated by monitoring the bending strength, open porosity, water absorption capability, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The Zn and Ag particles are distributed uniformly in the honeycomb ceramics and the crystalline structure of the ceramic materials is not altered after Zn and Ag incorporation consequently enabling good dispersion of the antibacterial metals

  4. Glass and ceramics. [lunar resources

    Science.gov (United States)

    Haskin, Larry A.

    1992-01-01

    A variety of glasses and ceramics can be produced from bulk lunar materials or from separated components. Glassy products include sintered regolith, quenched molten basalt, and transparent glass formed from fused plagioclase. No research has been carried out on lunar material or close simulants, so properties are not known in detail; however, common glass technologies such as molding and spinning seem feasible. Possible methods for producing glass and ceramic materials are discussed along with some potential uses of the resulting products.

  5. Nano-Ceramic Coated Plastics

    Science.gov (United States)

    Cho, Junghyun

    2013-01-01

    Plastic products, due to their durability, safety, and low manufacturing cost, are now rapidly replacing cookware items traditionally made of glass and ceramics. Despite this trend, some still prefer relatively expensive and more fragile ceramic/glassware because plastics can deteriorate over time after exposure to foods, which can generate odors, bad appearance, and/or color change. Nano-ceramic coatings can eliminate these drawbacks while still retaining the advantages of the plastic, since the coating only alters the surface of the plastic. The surface coating adds functionality to the plastics such as self-cleaning and disinfectant capabilities that result from a photocatalytic effect of certain ceramic systems. These ceramic coatings can also provide non-stick surfaces and higher temperature capabilities for the base plastics without resorting to ceramic or glass materials. Titanium dioxide (TiO2) and zinc oxide (ZnO) are the candidates for a nano-ceramic coating to deposit on the plastics or plastic films used in cookware and kitchenware. Both are wide-bandgap semiconductors (3.0 to 3.2 eV for TiO2 and 3.2 to 3.3 eV for ZnO), so they exhibit a photocatalytic property under ultraviolet (UV) light. This will lead to decomposition of organic compounds. Decomposed products can be easily washed off by water, so the use of detergents will be minimal. High-crystalline film with large surface area for the reaction is essential to guarantee good photocatalytic performance of these oxides. Low-temperature processing (nano-ceramic coatings (TiO2, ZnO) on plastic materials (silicone, Teflon, PET, etc.) that can possess both photocatalytic oxide properties and flexible plastic properties. Processing cost is low and it does not require any expensive equipment investment. Processing can be scalable to current manufacturing infrastructure.

  6. Batch compositions for cordierite ceramics

    Science.gov (United States)

    Hickman, David L.

    1994-07-26

    Ceramic products consisting principally of cordierite and a method for making them are provided, the method employing batches comprising a mineral component and a chemical component, the mineral component comprising clay and talc and the chemical component consisting essentially of a combination of the powdered oxides, hydroxides, or hydrous oxides of magnesium, aluminum and silicon. Ceramics made by extrusion and firing of the batches can exhibit low porosity, high strength and low thermal expansion coefficients.

  7. Novel Synthesis of Ceramic Films

    Institute of Scientific and Technical Information of China (English)

    K.L.Choy

    2007-01-01

    1 Results There is an increasing demand for producing high performance ceramic films at a reduced cost. This paper describes an innovative and cost-effective method of producing nanostructured ceramic films based on Electrostatic Spray Assisted Vapour Deposition (ESAVD). ESAVD is a variant of chemical vapour deposition process which involves spraying atomised charged precursor droplets across an electric field where the precursor undergo decomposition and heterogeneous chemical reaction near the heat...

  8. Method for Waterproofing Ceramic Materials

    Science.gov (United States)

    Cagliostro, Domenick E. (Inventor); Hsu, Ming-Ta S. (Inventor)

    1998-01-01

    Hygroscopic ceramic materials which are difficult to waterproof with a silane, substituted silane or silazane waterproofing agent, such as an alumina containing fibrous, flexible and porous, fibrous ceramic insulation used on a reentry space vehicle, are rendered easy to waterproof if the interior porous surface of the ceramic is first coated with a thin coating of silica. The silica coating is achieved by coating the interior surface of the ceramic with a silica precursor converting the precursor to silica either in-situ or by oxidative pyrolysis and then applying the waterproofing agent to the silica coated ceramic. The silica precursor comprises almost any suitable silicon containing material such as a silane, silicone, siloxane, silazane and the like applied by solution, vapor deposition and the like. If the waterproofing is removed by e.g., burning, the silica remains and the ceramic is easily rewaterproofed. An alumina containing TABI insulation which absorbs more that five times its weight of water, absorbs less than 10 wt. % water after being waterproofed according to the method of the invention.

  9. Rare-earth doped transparent ceramics for spectral filtering and quantum information processing

    Directory of Open Access Journals (Sweden)

    Nathalie Kunkel

    2015-09-01

    Full Text Available Homogeneous linewidths below 10 kHz are reported for the first time in high-quality Eu3+ doped Y 2O3 transparent ceramics. This result is obtained on the 7F0→5D0 transition in Eu3+ doped Y 2O3 ceramics and corresponds to an improvement of nearly one order of magnitude compared to previously reported values in transparent ceramics. Furthermore, we observed spectral hole lifetimes of ∼15 min that are long enough to enable efficient optical pumping of the nuclear hyperfine levels. Additionally, different Eu3+ concentrations (up to 1.0% were studied, resulting in an increase of up to a factor of three in the peak absorption coefficient. These results suggest that transparent ceramics can be useful in applications where narrow and deep spectral holes can be burned into highly absorbing lines, such as quantum information processing and spectral filtering.

  10. Rare-earth doped transparent ceramics for spectral filtering and quantum information processing

    Science.gov (United States)

    Kunkel, Nathalie; Ferrier, Alban; Thiel, Charles W.; Ramírez, Mariola O.; Bausá, Luisa E.; Cone, Rufus L.; Ikesue, Akio; Goldner, Philippe

    2015-09-01

    Homogeneous linewidths below 10 kHz are reported for the first time in high-quality Eu3+ doped Y 2O3 transparent ceramics. This result is obtained on the 7F0→5D0 transition in Eu3+ doped Y 2O3 ceramics and corresponds to an improvement of nearly one order of magnitude compared to previously reported values in transparent ceramics. Furthermore, we observed spectral hole lifetimes of ˜15 min that are long enough to enable efficient optical pumping of the nuclear hyperfine levels. Additionally, different Eu3+ concentrations (up to 1.0%) were studied, resulting in an increase of up to a factor of three in the peak absorption coefficient. These results suggest that transparent ceramics can be useful in applications where narrow and deep spectral holes can be burned into highly absorbing lines, such as quantum information processing and spectral filtering.

  11. Rare-earth doped transparent ceramics for spectral filtering and quantum information processing

    International Nuclear Information System (INIS)

    Homogeneous linewidths below 10 kHz are reported for the first time in high-quality Eu3+ doped Y 2O3 transparent ceramics. This result is obtained on the 7F0→5D0 transition in Eu3+ doped Y 2O3 ceramics and corresponds to an improvement of nearly one order of magnitude compared to previously reported values in transparent ceramics. Furthermore, we observed spectral hole lifetimes of ∼15 min that are long enough to enable efficient optical pumping of the nuclear hyperfine levels. Additionally, different Eu3+ concentrations (up to 1.0%) were studied, resulting in an increase of up to a factor of three in the peak absorption coefficient. These results suggest that transparent ceramics can be useful in applications where narrow and deep spectral holes can be burned into highly absorbing lines, such as quantum information processing and spectral filtering

  12. One Step Biomass Gas Reforming-Shift Separation Membrane Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, Michael J. [Gas Technology Institute; Souleimanova, Razima [Gas Technology Institute

    2012-12-28

    GTI developed a plan where efforts were concentrated in 4 major areas: membrane material development, membrane module development, membrane process development, and membrane gasifier scale-up. GTI assembled a team of researchers to work in each area. Task 1.1 Ceramic Membrane Synthesis and Testing was conducted by Arizona State University (ASU), Task 1.2 Metallic Membrane Synthesis and Testing was conducted by the U.S. National Energy Technology Laboratory (NETL), Task 1.3 was conducted by SCHOTT, and GTI was to test all membranes that showed potential. The initial focus of the project was concentrated on membrane material development. Metallic and glass-based membranes were identified as hydrogen selective membranes under the conditions of the biomass gasification, temperatures above 700C and pressures up to 30 atmospheres. Membranes were synthesized by arc-rolling for metallic type membranes and incorporating Pd into a glass matrix for glass membranes. Testing for hydrogen permeability properties were completed and the effects of hydrogen sulfide and carbon monoxide were investigated for perspective membranes. The initial candidate membrane of Pd80Cu20 chosen in 2008 was selected for preliminary reactor design and cost estimates. Although the H2A analysis results indicated a $1.96 cost per gge H2 based on a 5A (micron) thick PdCu membrane, there was not long-term operation at the required flux to satisfy the go/no go decision. Since the future PSA case yielded a $2.00/gge H2, DOE decided that there was insufficient savings compared with the already proven PSA technology to further pursue the membrane reactor design. All ceramic membranes synthesized by ASU during the project showed low hydrogen flux as compared with metallic membranes. The best ceramic membrane showed hydrogen permeation flux of 0.03 SCFH/ft2 at the required process conditions while the metallic membrane, Pd80Cu20 showed a flux of 47.2 SCFH/ft2 (3 orders of magnitude difference). Results from

  13. Ferroelectric ceramics in a pyroelectric accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Shchagin, A. V., E-mail: shchagin@kipt.kharkov.ua [Kharkov Institute of Physics and Technology, Kharkov 61108 (Ukraine); Belgorod State University, Belgorod 308015 (Russian Federation); Miroshnik, V. S.; Volkov, V. I. [Kharkov Institute of Physics and Technology, Kharkov 61108 (Ukraine); Oleinik, A. N. [Belgorod State University, Belgorod 308015 (Russian Federation)

    2015-12-07

    The applicability of polarized ferroelectric ceramics as a pyroelectric in a pyroelectric accelerator is shown by experiments. The spectra of X-ray radiation of energy up to tens of keV, generated by accelerated electrons, have been measured on heating and cooling of the ceramics in vacuum. It is suggested that curved layers of polarized ferroelectric ceramics be used as elements of ceramic pyroelectric accelerators. Besides, nanotubes and nanowires manufactured from ferroelectric ceramics are proposed for the use in nanometer-scale ceramic pyroelectric nanoaccelerators for future applications in nanotechnologies.

  14. Four-port gas separation membrane module assembly

    Science.gov (United States)

    Wynn, Nicholas P.; Fulton, Donald A.; Lokhandwala, Kaaeid A.; Kaschemekat, Jurgen

    2010-07-20

    A gas-separation membrane assembly, and a gas-separation process using the assembly. The assembly incorporates multiple gas-separation membranes in an array within a single vessel or housing, and is equipped with two permeate ports, enabling permeate gas to be withdrawn from both ends of the membrane module permeate pipes.

  15. High flux and antifouling properties of negatively charged membrane for dyeing wastewater treatment by membrane distillation.

    Science.gov (United States)

    An, Alicia Kyoungjin; Guo, Jiaxin; Jeong, Sanghyun; Lee, Eui-Jong; Tabatabai, S Assiyeh Alizadeh; Leiknes, TorOve

    2016-10-15

    This study investigated the applicability of membrane distillation (MD) to treat dyeing wastewater discharged by the textile industry. Four different dyes containing methylene blue (MB), crystal violet (CV), acid red 18 (AR18), and acid yellow 36 (AY36) were tested. Two types of hydrophobic membranes made of polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF) were used. The membranes were characterized by testing against each dye (foulant-foulant) and the membrane-dye (membrane-foulant) interfacial interactions and their mechanisms were identified. The MD membranes possessed negative charges, which facilitated the treatment of acid and azo dyes of the same charge and showed higher fluxes. In addition, PTFE membrane reduced the wettability with higher hydrophobicity of the membrane surface. The PTFE membrane evidenced especially its resistant to dye absorption, as its strong negative charge and chemical structure caused a flake-like (loose) dye-dye structure to form on the membrane surface rather than in the membrane pores. This also enabled the recovery of flux and membrane properties by water flushing (WF), thereby direct-contact MD with PTFE membrane treating 100 mg/L of dye mixtures showed stable flux and superior color removal during five days operation. Thus, MD shows a potential for stable long-term operation in conjunction with a simple membrane cleaning process, and its suitability in dyeing wastewater treatment. PMID:27486044

  16. Rheological Behaviour of Ceramic Inks for Direct Ceramic Inkjet Printing

    Directory of Open Access Journals (Sweden)

    P. Ponnambalam

    2006-04-01

    Full Text Available In this paper, studies were made on the preparation of ceramic inks with: (i alumina powderin ethyl alcohol and (ii zirconia powder in ethyl alcohol at different volume fractions of ceramic.Different amounts (0.75-3.00 vol % of an organic dispersant (oleic acid were added to ceramicink containing 5 per cent of ceramic by volume in ethyl alcohol. The viscosities of the suspensionswere determined with Brookefield viscometer (model: DV-E, which is suitable for measuringthe viscosities of suspensions accurately. These inks were deposited on a substrate to see theirspread. The sediment packing densities ( m of the resulting suspensions were calculated usingtheoretical models which can be related to the density that can be achieved in the final product.The highest sediment packing density was arrived at low viscosity values of the ink and occurredwhen 1 per cent of dispersant by volume was used for 5 per cent alumina content. For 5 percent zirconia content, 2 per cent of dispersant by volume gave a similar result. Experimentswere also conducted to find the value of m for different solid loadings (5-25 vol % of ceramicwith 1 per cent dispersant. It was observed that the sediment packing density and the apparentviscosities were increasing when solid loading concentrations were increased for both aluminaand zirconia-based inks. The optimum value of m and viscosity have been determined from thisstudy. The results of this preliminary study will be useful for further investigations on therheological behaviour of ceramic inks for direct ceramic inkjet printing.

  17. Axionic membranes

    Energy Technology Data Exchange (ETDEWEB)

    Aurilia, A. (Dept. of Physics, California State Polytechnic Univ., Pomona, CA (United States)); Spallucci, E. (Dipt. di Fisica Teorica, Univ. Trieste (Italy) INFN, Sezione Trieste (Italy))

    1992-05-21

    A metal ring removed from a soap-water solution encloses a film of soap which can be mathematically described as a minimal surface having the ring as its only boundary. This is known to everybody. In this letter we suggest a relativistic extension of the above fluidodynamic system where the soap film is replaced by a Kalb-Ramand gauge potential B{sub {mu}{nu}}(x) and the ring by a closed string. The interaction between the B{sub {mu}{nu}} field and the string current excites a new configuration of the system consisting of a relativistic membrane bounded by the string. We call such a classical solution of the equation of motion an axionic membrane. As a dynamical system, the axionic membrane admits a Hamilton-Jacobi formulation which is an extension of the HJ theory of electromagnetic strings. (orig.).

  18. Performance of Ceramics in Severe Environments

    Science.gov (United States)

    Jacobson, Nathan S.; Fox, Dennis S.; Smialek, James L.; Deliacorte, Christopher; Lee, Kang N.

    2005-01-01

    Ceramics are generally stable to higher temperatures than most metals and alloys. Thus the development of high temperature structural ceramics has been an area of active research for many years. While the dream of a ceramic heat engine still faces many challenges, niche markets are developing for these materials at high temperatures. In these applications, ceramics are exposed not only to high temperatures but also aggressive gases and deposits. In this chapter we review the response of ceramic materials to these environments. We discuss corrosion mechanisms, the relative importance of a particular corrodent, and, where available, corrosion rates. Most of the available corrosion information is on silicon carbide (SIC) and silicon nitride (Si3N4) monolithic ceramics. These materials form a stable film of silica (SO2) in an oxidizing environment. We begin with a discussion of oxidation of these materials and proceed to the effects of other corrodents such as water vapor and salt deposits. We also discuss oxidation and corrosion of other ceramics: precurser derived ceramics, ceramic matrix composites (CMCs), ceramics which form oxide scales other than silica, and oxide ceramics. Many of the corrosion issues discussed can be mitigated with refractory oxide coatings and we discuss the current status of this active area of research. Ultimately, the concern of corrosion is loss of load bearing capability. We discuss the effects of corrosive environments on the strength of ceramics, both monolithic and composite. We conclude with a discussion of high temperature wear of ceramics, another important form of degradation at high temperatures.

  19. Nanomaterial-enabled neural stimulation

    OpenAIRE

    Yongchen eWang; Liang eGuo

    2016-01-01

    Neural stimulation is a critical technique in treating neurological diseases and investigating brain functions. Traditional electrical stimulation uses electrodes to directly create intervening electric fields in the immediate vicinity of neural tissues. Second-generation stimulation techniques directly use light, magnetic fields or ultrasound in a non-contact manner. An emerging generation of non- or minimally invasive neural stimulation techniques is enabled by nanotechnology to achieve a h...

  20. Nanomaterial-Enabled Neural Stimulation

    OpenAIRE

    Wang, Yongchen; Guo, Liang

    2016-01-01

    Neural stimulation is a critical technique in treating neurological diseases and investigating brain functions. Traditional electrical stimulation uses electrodes to directly create intervening electric fields in the immediate vicinity of neural tissues. Second-generation stimulation techniques directly use light, magnetic fields or ultrasound in a non-contact manner. An emerging generation of non- or minimally invasive neural stimulation techniques is enabled by nanotechnology to achieve a h...

  1. 'Ethos' Enabling Organisational Knowledge Creation

    Science.gov (United States)

    Matsudaira, Yoshito

    This paper examines knowledge creation in relation to improvements on the production line in the manufacturing department of Nissan Motor Company and aims to clarify embodied knowledge observed in the actions of organisational members who enable knowledge creation will be clarified. For that purpose, this study adopts an approach that adds a first, second, and third-person's viewpoint to the theory of knowledge creation. Embodied knowledge, observed in the actions of organisational members who enable knowledge creation, is the continued practice of 'ethos' (in Greek) founded in Nissan Production Way as an ethical basis. Ethos is knowledge (intangible) assets for knowledge creating companies. Substantiated analysis classifies ethos into three categories: the individual, team and organisation. This indicates the precise actions of the organisational members in each category during the knowledge creation process. This research will be successful in its role of showing the indispensability of ethos - the new concept of knowledge assets, which enables knowledge creation -for future knowledge-based management in the knowledge society.

  2. Ceramic HEPA Filter Program

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, M A; Bergman, W; Haslam, J; Brown, E P; Sawyer, S; Beaulieu, R; Althouse, P; Meike, A

    2012-04-30

    Potential benefits of ceramic filters in nuclear facilities: (1) Short term benefit for DOE, NRC, and industry - (a) CalPoly HTTU provides unique testing capability to answer questions for DOE - High temperature testing of materials, components, filter, (b) Several DNFSB correspondences and presentations by DNFSB members have highlighted the need for HEPA filter R and D - DNFSB Recommendation 2009-2 highlighted a nuclear facility response to an evaluation basis earthquake followed by a fire (aka shake-n-bake) and CalPoly has capability for a shake-n-bake test; (2) Intermediate term benefit for DOE and industry - (a) Filtration for specialty applications, e.g., explosive applications at Nevada, (b) Spin-off technologies applicable to other commercial industries; and (3) Long term benefit for DOE, NRC, and industry - (a) Across industry, strong desire for better performance filter, (b) Engineering solution to safety problem will improve facility safety and decrease dependence on associated support systems, (c) Large potential life-cycle cost savings, and (d) Facilitates development and deployment of LLNL process innovations to allow continuous ventilation system operation during a fire.

  3. Ceramic HEPA Filter Program

    International Nuclear Information System (INIS)

    Potential benefits of ceramic filters in nuclear facilities: (1) Short term benefit for DOE, NRC, and industry - (a) CalPoly HTTU provides unique testing capability to answer questions for DOE - High temperature testing of materials, components, filter, (b) Several DNFSB correspondences and presentations by DNFSB members have highlighted the need for HEPA filter R and D - DNFSB Recommendation 2009-2 highlighted a nuclear facility response to an evaluation basis earthquake followed by a fire (aka shake-n-bake) and CalPoly has capability for a shake-n-bake test; (2) Intermediate term benefit for DOE and industry - (a) Filtration for specialty applications, e.g., explosive applications at Nevada, (b) Spin-off technologies applicable to other commercial industries; and (3) Long term benefit for DOE, NRC, and industry - (a) Across industry, strong desire for better performance filter, (b) Engineering solution to safety problem will improve facility safety and decrease dependence on associated support systems, (c) Large potential life-cycle cost savings, and (d) Facilitates development and deployment of LLNL process innovations to allow continuous ventilation system operation during a fire.

  4. Antiferroelectric Shape Memory Ceramics

    Directory of Open Access Journals (Sweden)

    Kenji Uchino

    2016-05-01

    Full Text Available Antiferroelectrics (AFE can exhibit a “shape memory function controllable by electric field”, with huge isotropic volumetric expansion (0.26% associated with the AFE to Ferroelectric (FE phase transformation. Small inverse electric field application can realize the original AFE phase. The response speed is quick (2.5 ms. In the Pb0.99Nb0.02[(Zr0.6Sn0.41-yTiy]0.98O3 (PNZST system, the shape memory function is observed in the intermediate range between high temperature AFE and low temperature FE, or low Ti-concentration AFE and high Ti-concentration FE in the composition. In the AFE multilayer actuators (MLAs, the crack is initiated in the center of a pair of internal electrodes under cyclic electric field, rather than the edge area of the internal electrodes in normal piezoelectric MLAs. The two-sublattice polarization coupling model is proposed to explain: (1 isotropic volume expansion during the AFE-FE transformation; and (2 piezoelectric anisotropy. We introduce latching relays and mechanical clampers as possible unique applications of shape memory ceramics.

  5. Biomimetic processing of oriented crystalline ceramic layers

    Energy Technology Data Exchange (ETDEWEB)

    Cesarano, J.; Shelnutt, J.A.

    1997-10-01

    The aim of this project was to develop the capabilities for Sandia to fabricate self assembled Langmuir-Blodgett (LB) films of various materials and to exploit their two-dimensional crystalline structure to promote the growth of oriented thin films of inorganic materials at room temperature. This includes the design and synthesis of Langmuir-active (amphiphilic) organic molecules with end groups offering high nucleation potential for various ceramics. A longer range goal is that of understanding the underlying principles, making it feasible to use the techniques presented in this report to fabricate unique oriented films of various materials for electronic, sensor, and membrane applications. Therefore, whenever possible, work completed in this report was completed with the intention of addressing the fundamental phenomena underlying the growth of crystalline, inorganic films on template layers of highly organized organic molecules. This problem was inspired by biological processes, which often produce exquisitely engineered structures via templated growth on polymeric layers. Seashells, for example, exhibit great toughness owing to their fine brick-and-mortar structure that results from templated growth of calcium carbonate on top of layers of ordered organic proteins. A key goal in this work, therefore, is to demonstrate a positive correlation between the order and orientation of the template layer and that of the crystalline ceramic material grown upon it. The work completed was comprised of several parallel efforts that encompassed the entire spectrum of biomimetic growth from solution. Studies were completed on seashells and the mechanisms of growth for calcium carbonate. Studies were completed on the characterization of LB films and the capability developed for the in-house fabrication of these films. Standard films of fatty acids were studied as well as novel polypeptides and porphyrins that were synthesized.

  6. Composite membranes and methods for making same

    Science.gov (United States)

    Routkevitch, Dmitri; Polyakov, Oleg G

    2012-07-03

    Composite membranes that are adapted for separation, purification, filtration, analysis, reaction and sensing. The composite membranes can include a porous support structure having elongate pore channels extending through the support structure. The composite membrane also includes an active layer comprising an active layer material, where the active layer material is completely disposed within the pore channels between the surfaces of the support structure. The active layer is intimately integrated within the support structure, thus enabling great robustness, reliability, resistance to mechanical stress and thermal cycling, and high selectivity. Methods for the fabrication of composite membranes are also provided.

  7. Proteomics and the dynamic plasma membrane

    DEFF Research Database (Denmark)

    Sprenger, Richard R; Jensen, Ole Nørregaard

    2010-01-01

    plasma membrane is of particular interest, by not only serving as a barrier between the "cell interior" and the external environment, but moreover by organizing and clustering essential components to enable dynamic responses to internal and external stimuli. Defining and characterizing the dynamic plasma...... the challenges in functional proteomic studies of the plasma membrane. We review the recent progress in MS-based plasma membrane proteomics by presenting key examples from eukaryotic systems, including mammals, yeast and plants. We highlight the importance of enrichment and quantification technologies...... required for detailed functional and comparative analysis of the dynamic plasma membrane proteome....

  8. Oxygen Transport Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay

    2008-08-30

    dominated the fracture origins and the overall fracture was purely transgranular. The dual phase membranes have been evaluated for structural properties. An increasing crack growth resistance was observed for the membranes heat-treated at 1000 C in air and N{sub 2} with increasing crack length. The combined effect of thermal and elastic mismatch stresses on the crack path was studied and the fracture behavior of the dual phase composite at the test conditions was analyzed. Ceramic/metal (C/M) seals are needed to form a leak-tight interface between the OTM and a nickel-base super alloy. It was concluded that Ni-based brazing alloys provided the best option in terms of brazing temperature and final operating conditions after analyzing several possible brazing systems. A mechanical testing procedure has been developed. This model was tested with model ceramic/metal systems but it is expected to be useful for testing concentric perovskite/metal seals.

  9. Panel report on high temperature ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Nolet, T C [ed.

    1979-01-01

    Fundamental research is reported concerning high temperature ceramics for application in turbines, engines, batteries, gasifiers, MHD, fuel cells, heat exchangers, and hot wall combustors. Ceramics microstructure and behavior are included. (FS)

  10. III Advanced Ceramics and Applications Conference

    CERN Document Server

    Gadow, Rainer; Mitic, Vojislav; Obradovic, Nina

    2016-01-01

    This is the Proceedings of III Advanced Ceramics and Applications conference, held in Belgrade, Serbia in 2014. It contains 25 papers on various subjects regarding preparation, characterization and application of advanced ceramic materials.

  11. Robotic membranes

    DEFF Research Database (Denmark)

    Ramsgaard Thomsen, Mette

    2008-01-01

    prototypes, Vivisection and Strange Metabolisms, were developed at the Centre for Information Technology and Architecture (CITA) at the Royal Danish Academy of Fine Arts in Copenhagen as a means of engaging intangible digital data with tactile physical material. As robotic membranes, they are a dual...

  12. Development of advanced ceramics at AECL

    International Nuclear Information System (INIS)

    Atomic Energy of Canada Limited (AECL) has a long history of developing ceramics for nuclear fission and fusion applications. AECL is now applying its multidisciplinary materials R and D capabilities, including unique capabilities in ceramic processing and nondestructive evaluation, to develop advanced ceramic materials for commercial and industrial applications. This report provides an overview of the facilities and programs associated with the development of advanced ceramics at AECL

  13. Emerging Ceramic-based Materials for Dentistry

    OpenAIRE

    Denry, I.; Kelly, J. R.

    2014-01-01

    Our goal is to give an overview of a selection of emerging ceramics and issues for dental or biomedical applications, with emphasis on specific challenges associated with full-contour zirconia ceramics, and a brief synopsis on new machinable glass-ceramics and ceramic-based interpenetrating phase composites. Selected fabrication techniques relevant to dental or biomedical applications such as microwave sintering, spark plasma sintering, and additive manufacturing are also reviewed. Where appr...

  14. Emerging Ceramic-based Materials for Dentistry

    Science.gov (United States)

    Denry, I.; Kelly, J.R.

    2014-01-01

    Our goal is to give an overview of a selection of emerging ceramics and issues for dental or biomedical applications, with emphasis on specific challenges associated with full-contour zirconia ceramics, and a brief synopsis on new machinable glass-ceramics and ceramic-based interpenetrating phase composites. Selected fabrication techniques relevant to dental or biomedical applications such as microwave sintering, spark plasma sintering, and additive manufacturing are also reviewed. Where appropriate, the authors have added their opinions and guidance. PMID:25274751

  15. Comparing Nafion and ceramic separators used in electrochemical purification of spent chromium plating solutions: cationic impurity removal and transport.

    Science.gov (United States)

    Huang, Kuo-Lin; Holsen, Thomas M; Chou, Tse-Chuan; Selman, J Robert

    2003-05-01

    This study focuses on the electrolytic regeneration of spent chromium plating solutions. These solutions contain a significant amount of chromium and a lesser amount of other heavy metals, which makes them a significant environmental concern and an obvious target for recycling and reuse. The type of separator used is extremely critical to the performance of the process because they are the major resistance in the transport-related impurity (Cu(II), Ni(II), and Fe(III)) removals from contaminated chromic acid solutions. A Nafion 117 membrane and a ceramic diaphragm separator traditionally used in the industry were tested for comparison. It was found that the mobilities of Cu(II) and Ni(II) were similar and higher than that of Fe(III) using both separators. The mobility of each cation was smaller in the Nafion membrane than in the ceramic diaphragm. The measured conductivity of the ceramic diaphragm was slightly higher than that of Nafion membrane. However, the Nafion membrane was much thinner than the ceramic diaphragm resulting in the system using the Nafion membrane having higher impurity removal rates than the system using the ceramic diaphragm. The removal rates were approximately equal for Cu(II) and Ni(II) and lowest for Fe(III). Both current and initial concentration affected the removal rates of the impurities. Modeling results indicated that a system using a Nafion separator and a small catholyte/anolyte volume ratio was better than a system using a ceramic separator for removing impurities from concentrated plating solutions if the impurities transported into the catholyte are deposited or precipitated. PMID:12775076

  16. Methodology for life cycle assessment of ceramic floor and wall tiles - applications in BAT definition for ceramic tiles industry

    Energy Technology Data Exchange (ETDEWEB)

    Rinaldi, C.; Fregni, A.; Palmonari, C.; Timellini, G. [Centro Ceramico, Bologna (Italy)

    2002-07-01

    In order to manage the new European approach to the protection of the environment, based on the prevention of pollution starting from the design of new products and production techniques, ceramic industries need new specific analysis tools, such as life cycle assessment. A Life Cycle Assessment procedure specific for ceramic tiles industry has been developed [1] and used to compare the environmental performances of different products and technologies. Attention has been focused, in particular, on techniques having cross media effects (for example, the purification of gaseous emissions and cogeneration). The identification and quantification of the possible environmental benefits or risks associated to these techniques, enable the development of design criteria for measures intended to achieve an integrated pollution prevention and reduction, and thus a global protection of the whole environment. (orig.)

  17. IM30 triggers membrane fusion in cyanobacteria and chloroplasts.

    Science.gov (United States)

    Hennig, Raoul; Heidrich, Jennifer; Saur, Michael; Schmüser, Lars; Roeters, Steven J; Hellmann, Nadja; Woutersen, Sander; Bonn, Mischa; Weidner, Tobias; Markl, Jürgen; Schneider, Dirk

    2015-01-01

    The thylakoid membrane of chloroplasts and cyanobacteria is a unique internal membrane system harbouring the complexes of the photosynthetic electron transfer chain. Despite their apparent importance, little is known about the biogenesis and maintenance of thylakoid membranes. Although membrane fusion events are essential for the formation of thylakoid membranes, proteins involved in membrane fusion have yet to be identified in photosynthetic cells or organelles. Here we show that IM30, a conserved chloroplast and cyanobacterial protein of approximately 30 kDa binds as an oligomeric ring in a well-defined geometry specifically to membranes containing anionic lipids. Triggered by Mg(2+), membrane binding causes destabilization and eventually results in membrane fusion. We propose that IM30 establishes contacts between internal membrane sites and promotes fusion to enable regulated exchange of proteins and/or lipids in cyanobacteria and chloroplasts. PMID:25952141

  18. Insights on Ceramics as Dental Materials. Part I: Ceramic Material Types in Dentistry

    OpenAIRE

    Ho, GW; Matinlinna, JP

    2011-01-01

    Ceramics are widely used biomaterials in prosthetic dentistry due to their attractive clinical properties. They are aesthetically pleasing with their color, shade and luster, and they are chemically stable. The main constituents of dental ceramic are Si-based inorganic materials, such as feldspar, quartz, and silica. Traditional feldspar-based ceramics are also referred to as "Porcelain". The crucial difference between a regular ceramic and a dental ceramic is the proportion of feldspar, quar...

  19. Water: A Critical Material Enabling Space Exploration

    Science.gov (United States)

    Pickering, Karen D.

    2014-01-01

    Water is one of the most critical materials in human spaceflight. The availability of water defines the duration of a space mission; the volume of water required for a long-duration space mission becomes too large, heavy, and expensive for launch vehicles to carry. Since the mission duration is limited by the amount of water a space vehicle can carry, the capability to recycle water enables space exploration. In addition, water management in microgravity impacts spaceflight in other respects, such as the recent emergency termination of a spacewalk caused by free water in an astronaut's spacesuit helmet. A variety of separation technologies are used onboard spacecraft to ensure that water is always available for use, and meets the stringent water quality required for human space exploration. These separation technologies are often adapted for use in a microgravity environment, where water behaves in unique ways. The use of distillation, membrane processes, ion exchange and granular activated carbon will be reviewed. Examples of microgravity effects on operations will also be presented. A roadmap for future technologies, needed to supply water resources for the exploration of Mars, will also be reviewed.

  20. Character of extracellular polymeric substances and soluble microbial products and their effect on membrane hydraulics during airlift membrane bioreactor applications.

    Science.gov (United States)

    Alvarez-Vazquez, Hector; Pidou, Marc; Holdner, Jennifer; Judd, Simon J

    2008-12-01

    The effect of extracellular polymeric substances and soluble microbial products developed from wastewater and mature landfill leachate biomass was assessed using a pilot-scale membrane bioreactor operating polymeric and ceramic air-lift sidestream multichannel membranes. The plant was operated under identical conditions of sludge retention time, system hydrodynamics ,and parity of food-to-microorganism ratios. Biomass samples were extracted and fractionated (fixed and bound material, carbohydrate and protein extracts) and chemically and physically analyzed with the feedwaters. Both ceramic and polymeric membranes were tested and the critical flux (J(C)) determined according to the classical flux-step analysis. Although permeability (K) of both materials reduced with increasing flux (J), the ceramic material had a higher resistance to fouling, demonstrating a higher K (by a factor of 1.2 and 3.2 for wastewater and leachate, respectively, at J of 30 L x m(-2) x h(-1)) and lower fouling rate (dP/dt) (by more than an order of magnitude at the same J) than the polymeric membrane. Evidence suggests that deterioration of membrane permeability resulting from leachate biomass arises from the feedwater itself, rather than the products derived from the biomass, and that colloidal and/or soluble total organic carbon is primarily responsible for it. PMID:19146096

  1. Automated Rapid Prototyping of 3D Ceramic Parts

    Science.gov (United States)

    McMillin, Scott G.; Griffin, Eugene A.; Griffin, Curtis W.; Coles, Peter W. H.; Engle, James D.

    2005-01-01

    An automated system of manufacturing equipment produces three-dimensional (3D) ceramic parts specified by computational models of the parts. The system implements an advanced, automated version of a generic rapid-prototyping process in which the fabrication of an object having a possibly complex 3D shape includes stacking of thin sheets, the outlines of which closely approximate the horizontal cross sections of the object at their respective heights. In this process, the thin sheets are made of a ceramic precursor material, and the stack is subsequently heated to transform it into a unitary ceramic object. In addition to the computer used to generate the computational model of the part to be fabricated, the equipment used in this process includes: 1) A commercially available laminated-object-manufacturing machine that was originally designed for building woodlike 3D objects from paper and was modified to accept sheets of ceramic precursor material, and 2) A machine designed specifically to feed single sheets of ceramic precursor material to the laminated-object-manufacturing machine. Like other rapid-prototyping processes that utilize stacking of thin sheets, this process begins with generation of the computational model of the part to be fabricated, followed by computational sectioning of the part into layers of predetermined thickness that collectively define the shape of the part. Information about each layer is transmitted to rapid-prototyping equipment, where the part is built layer by layer. What distinguishes this process from other rapid-prototyping processes that utilize stacking of thin sheets are the details of the machines and the actions that they perform. In this process, flexible sheets of ceramic precursor material (called "green" ceramic sheets) suitable for lamination are produced by tape casting. The binder used in the tape casting is specially formulated to enable lamination of layers with little or no applied heat or pressure. The tape is cut

  2. Thermoluminescence properties of AlN ceramics

    DEFF Research Database (Denmark)

    Trinkler, L.; Christensen, P.; Agersnap Larsen, N.; Berzina, B.

    The paper describes thermoluminescence (TL) properties of AlN:Y2O3 ceramics irradiated with ionising radiation. A high TL sensitivity of AlN:Y2O3 ceramics to radiation encouraged a study of the AlN ceramics for application as a dosimetric material. The paper presents experimental data on: glow...

  3. Gas separation with glass membranes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, D.L.; Abraham, L.C.; Blum, Y.; Way, J.D.

    1992-05-01

    The Department of Energy (DOE) is seeking to develop high temperature, high pressure inorganic membrane technology to perform a variety of gas separation processes to improve the efficiency and economics of advanced power generation systems such as direct coal-fueled turbines (DCFT) and the integrated gasification combined cycle process (IGCC). The temperatures encountered in these power generation systems are far above the temperature range for organic membrane materials. Inorganic materials such as ceramics are therefore the most likely membrane materials for use at high temperatures. This project focussed on silica glass fiber membranes made by PPG Industries (Pittsburgh, PA). The goals were both experimental and theoretical. The first objective was to develop a rational theory for the performance of these membranes. With existing theories as a starting point, a new theory was devised to explain the unusual ``molecular sieving`` behavior exhibited by these glass membranes. An apparatus was then devised for making permeation performance measurements at conditions of interest to DOE (temperatures to 2000{degrees}F; pressures to 1000 psia). With this apparatus, gas mixtures could be made typical of coal combustion or coal gasification processes, these gases could be passed into a membrane test cell, and the separation performance determined. Data were obtained for H{sub 2}/CO,N{sub 2}/CO{sub 2}, 0{sub 2}/N{sub 2}, and NH{sub 3}/N{sub 2} mixtures and for a variety of pure component gases (He, H{sub 2}, CO{sub 2}, N{sub 2}, CO, NH{sub 3}). The most challenging part of the project turned out to be the sealing of the membrane at high temperatures and pressures. The report concludes with an overview of the practical potential of these membranes and of inorganic membranes in general of DOE and other applications.

  4. Optimized microsystems-enabled photovoltaics

    Science.gov (United States)

    Cruz-Campa, Jose Luis; Nielson, Gregory N.; Young, Ralph W.; Resnick, Paul J.; Okandan, Murat; Gupta, Vipin P.

    2015-09-22

    Technologies pertaining to designing microsystems-enabled photovoltaic (MEPV) cells are described herein. A first restriction for a first parameter of an MEPV cell is received. Subsequently, a selection of a second parameter of the MEPV cell is received. Values for a plurality of parameters of the MEPV cell are computed such that the MEPV cell is optimized with respect to the second parameter, wherein the values for the plurality of parameters are computed based at least in part upon the restriction for the first parameter.

  5. Cosmological science enabled by Planck

    OpenAIRE

    White, Martin

    2006-01-01

    Planck will be the first mission to map the entire cosmic microwave background (CMB) sky with mJy sensitivity and resolution better than 10'. The science enabled by such a mission spans many areas of astrophysics and cosmology. In particular it will lead to a revolution in our understanding of primary and secondary CMB anisotropies, the constraints on many key cosmological parameters will be improved by almost an order of magnitude (to sub-percent levels) and the shape and amplitude of the ma...

  6. Dynamic properties of ceramic materials

    International Nuclear Information System (INIS)

    The present study offers new data and analysis on the transient shock strength and equation-of-state properties of ceramics. Various dynamic data on nine high strength ceramics are provided with wave profile measurements, through velocity interferometry techniques, the principal observable. Compressive failure in the shock wave front, with emphasis on brittle versus ductile mechanisms of deformation, is examined in some detail. Extensive spall strength data are provided and related to the theoretical spall strength, and to energy-based theories of the spall process. Failure waves, as a mechanism of deformation in the transient shock process, are examined. Strength and equation-of-state analysis of shock data on silicon carbide, boron carbide, tungsten carbide, silicon dioxide and aluminum nitride is presented with particular emphasis on phase transition properties for the latter two. Wave profile measurements on selected ceramics are investigated for evidence of rate sensitive elastic precursor decay in the shock front failure process

  7. Nondestructive evaluation of structural ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Klima, S.J.; Baaklini, G.Y.; Abel, P.B.

    1987-01-01

    A review is presented on research and development of techniques for nondestructive evaluation and characterization of advanced ceramics for heat engine applications. Highlighted in this review are Lewis Research Center efforts in microfocus radiography, scanning laser acoustic microscopy (SLAM), scanning acoustic microscopy (SAM), scanning electron acoustic microscopy (SEAM), and photoacoustic microscopy (PAM). The techniques were evaluated by applying them to research samples of green and sintered silicon nitride and silicon carbide in the form of modulus-of-rupture bars containing seeded voids. Probabilities of detection of voids were determined for diameters as small as 20 microns for microfucus radiography, SLAM, and SAM. Strengths and limitations of the techniques for ceramic applications are identified. Application of ultrasonics for characterizing ceramic microstructures is also discussed.

  8. Innovative processing of ceramic superconductors

    International Nuclear Information System (INIS)

    The discovery of high-temperature superconducting yttrium barium cuprate has changed the way we think about ceramics. It has broadened the perception and the definition of ceramic materials, and has attracted new workers from other fields such as chemistry, physics, and engineering, adding to the diversity of techniques used for synthesis and characterization. The authors are seeking to synthesize ceramics in a near-single-crystal configuration. They want to create a new class of material that may have wide-ranging applications, from sensors to optoelectronic devices to superconductive cables. This article I describes their approaches and some of preliminary results. A superconducting magnetic bearing and a high-current superconducting cable are possible applications of this work

  9. Ceramic materials testing and modeling

    Energy Technology Data Exchange (ETDEWEB)

    Wilfinger, K. R., LLNL

    1998-04-30

    Certain refractory ceramics (notably oxides) have desirable properties suitable for the construction of ceramic waste containers for long term use in nuclear waste disposal applications. In particular, they are far less prone to environmental corrosion than metals under realistic repository conditions. The aqueous corrosion rates of oxides such as magnesium aluminate spinel (MgAl{sub 2}0{sub 4}) and alumina (Al{sub 2}0{sub 4}) fall in the range of a few millimeters per million years. Oxide ceramics are also not likely to be subject to microbiologically influenced corrosion, which apparently can attack most, if not all, of the available engineering metals. Ceramics have a reputation for poor mechanical performance and large, impermeable objects are not easily fabricated by most current fabrication methods. As a result, the most promising approach for incorporating ceramics in large waste packages appears to be to apply a high density ceramic coating to a supporting metallic structure. Ceramic coatings 2048 applied by a thermal spray technique can be made effectively seamless and provide a method for final closure of the waste package while maintaining low average temperatures for the entire assembly. The corrosion resistance of the ceramic should prevent or delay water penetration to the underlying metal, which will in turn provide most of the mechanical strength and toughness required by the application. In this way, the major concerns regarding the ceramic coating become ensuring it is impervious to moisture, its adherence and its resistance to mechanical stresses during handling or resulting from rock fall in the repository. Without water, electrochemical corrosion and microbiologically influenced corrosion processes are considered impossible, so a complete coating should protect the metal vessels for far longer than the current design requirements. Even an imperfect coating should extend the life of the package, delaying the onset and reducing the severity of

  10. High flux and antifouling properties of negatively charged membrane for dyeing wastewater treatment by membrane distillation

    KAUST Repository

    An, Alicia Kyoungjin

    2016-07-25

    This study investigated the applicability of membrane distillation (MD) to treat dyeing wastewater discharged by the textile industry. Four different dyes containing methylene blue (MB), crystal violet (CV), acid red 18 (AR), and acid yellow 36 (AY) were tested. Two types of hydrophobic membranes made of polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF) were used. The membranes were characterized by testing against each dye (foulant-foulant) and the membrane–dye (membrane-foulant) interfacial interactions and their mechanisms were identified. The MD membranes possessed negative charges, which facilitated the treatment of acid and azo dyes of the same charge and showed higher fluxes. In addition, PTFE membrane reduced the wettability with higher hydrophobicity of the membrane surface. The PTFE membrane evidenced especially its resistant to dye absorption, as its strong negative charge and chemical structure caused a flake-like (loose) dye–dye structure to form on the membrane surface rather than in the membrane pores. This also enabled the recovery of flux and membrane properties by water flushing (WF), thereby direct-contact MD with PTFE membrane treating 100 mg/L of dye mixtures showed stable flux and superior color removal during five days operation. Thus, MD shows a potential for stable long-term operation in conjunction with a simple membrane cleaning process, and its suitability in dyeing wastewater treatment.

  11. Composite Membrane with Underwater-Oleophobic Surface for Anti-Oil-Fouling Membrane Distillation.

    Science.gov (United States)

    Wang, Zhangxin; Hou, Deyin; Lin, Shihong

    2016-04-01

    In this study, we fabricated a composite membrane for membrane distillation (MD) by modifying a commercial hydrophobic polyvinylidene fluoride (PVDF) membrane with a nanocomposite coating comprising silica nanoparticles, chitosan hydrogel and fluoro-polymer. The composite membrane exhibits asymmetric wettability, with the modified surface being in-air hydrophilic and underwater oleophobic, and the unmodified surface remaining hydrophobic. By comparing the performance of the composite membrane and the pristine PVDF membrane in direct contact MD experiments using a saline emulsion with 1000 ppm crude oil (in water), we showed that the fabricated composite membrane was significantly more resistant to oil fouling compared to the pristine hydrophobic PVDF membrane. Force spectroscopy was conducted for the interaction between an oil droplet and the membrane surface using a force tensiometer. The difference between the composite membrane and the pristine PVDF membrane in their interaction with an oil droplet served to explain the difference in the fouling propensities between these two membranes observed in MD experiments. The results from this study suggest that underwater oleophobic coating can effectively mitigate oil fouling in MD operations, and that the fabricated composite membrane with asymmetric wettability can enable MD to desalinate hypersaline wastewater with high concentrations of hydrophobic contaminants. PMID:26958985

  12. Ceramic catalyst materials

    Energy Technology Data Exchange (ETDEWEB)

    Sault, A.G.; Gardner, T.J. [Sandia National Laboratories, Albuquerque, NM (United States); Hanprasopwattanna, A.; Reardon, J.; Datye, A.K. [Univ. of New Mexico, Albuquerque, NM (United States)

    1995-08-01

    Hydrous titanium oxide (HTO) ion-exchange materials show great potential as ceramic catalyst supports due to an inherently high ion-exchange capacity which allows facile loading of catalytically active transition metal ions, and an ability to be cast as thin films on virtually any substrate. By coating titania and HTO materials onto inexpensive, high surface area substrates such as silica and alumina, the economics of using these materials is greatly improved, particularly for the HTO materials, which are substantially more expensive in the bulk form than other oxide supports. In addition, the development of thin film forms of these materials allows the catalytic and mechanical properties of the final catalyst formulation to be separately engineered. In order to fully realize the potential of thin film forms of titania and HTO, improved methods for the deposition and characterization of titania and HTO films on high surface area substrates are being developed. By varying deposition procedures, titania film thickness and substrate coverage can be varied from the submonolayer range to multilayer thicknesses on both silica and alumina. HTO films can also be formed, but the quality and reproducibility of these films is not nearly as good as for pure titania films. The films are characterized using a combination of isopropanol dehydration rate measurements, point of zero charge (PZC) measurements, BET surface area, transmission electron microscopy (TEM), and elemental analysis. In order to assess the effects of changes in film morphology on catalytic activity, the films are being loaded with MoO{sub 3} using either incipient wetness impregnation or ion-exchange of heptamolybdate anions followed by calcining. The MoO{sub 3} is then sulfided to form MOS{sub 2}, and tested for catalytic activity using pyrene hydrogenation and dibenzothiophene (DBT) desulfurization, model reactions that simulate reactions occurring during coal liquefaction.

  13. Towards application of palladium membrane reactors in large scale production of hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Delft, Y.C.; Saric, M.; Overbeek, J.P.; De Groot, A.; Dijkstra, J.W.; Jansen, D. [ECN Hydrogen and Clean Fossil Fuels, Petten (Netherlands)

    2009-12-15

    Palladium membrane reactors have been identified as a promising option for hydrogen production in future power production systems and industrial chemical production processes. Dense tubular Pd alloy membranes with a high hydrogen permeance have been made on ceramic supports with electroless plating on a 1m{sup 2} scale. Application of a Pd membrane and a commercial catalyst in membrane reactor experiments have shown that it is possible to shift the methane conversion beyond chemical equilibrium by means of hydrogen withdrawal. A computer model of the palladium membrane reformer was developed and has been successfully used to evaluate the impact of main operating and design parameters on the reactor performance.

  14. wTuning microbial hosts for membrane protein production

    OpenAIRE

    Pichler Harald; Freigassner Maria; Glieder Anton

    2009-01-01

    Abstract The last four years have brought exciting progress in membrane protein research. Finally those many efforts that have been put into expression of eukaryotic membrane proteins are coming to fruition and enable to solve an ever-growing number of high resolution structures. In the past, many skilful optimization steps were required to achieve sufficient expression of functional membrane proteins. Optimization was performed individually for every membrane protein, but provided insight ab...

  15. Chemical characterization of marajoara ceramics

    International Nuclear Information System (INIS)

    In this study the elemental concentration of Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Rb, Sc, Sm, Ta, Tb, Th, U, Yb and Zn were determined by instrumental neutron activation analysis (INAA) in 204 fragments of Marajoara archaeological ceramics, of which 156 were provided by the Archaeology and Ethnology Museum of Sao Paulo University (MAE) and 48 were provided by Dr. Denise Pahl Schaan, Marajo Museum curator. Also, 9 contemporary ceramics produced and marketed at Marajo Island were analyzed. Electron paramagnetic resonance (EPR) analyses were performed in 8 archaeological samples and 1 contemporary sample in order to identify the burning temperature of the samples. X-ray diffraction (XRD) analyses were performed in 13 archaeological samples and 2 contemporary samples for the investigation of their mineralogical composition. Mahalanobis distance was used for the study of outlier while modified filter was used for the study of the temper added to the ceramic paste. Result interpretation was performed using cluster analysis, principal components analysis and discriminant analysis. Procrustes analysis was used for variable selection and it showed that the Ce, Fe, Eu, Hf, K and Th variables are adequate for the characterization of the analyzed samples. The comparative study among the archaeological and contemporary ceramics showed the arrangement of two well-defined and close groups for the archaeological samples and a third, distant group for the contemporary ones. This result indicates that the archaeological and contemporary ceramics differ in their composition. EPR and XRD analysis were inconclusive for the differentiation of archaeological and contemporary ceramics. (author)

  16. Ceramic Technologies for Sustainability: Perspectives from Siemens Corporate Technology

    Science.gov (United States)

    Rossner, W.

    2011-05-01

    Climate change, environmental care, energy efficiency, scarcity of resources, population growth, demographic change, urbanization and globalization are the most pressing questions in the coming century. They will have an effect on all regions and groups of global society. Effective solutions will require immediate, efficient and concerted activities in all areas at the social, economic and environmental level. Since the 1980s it has been understood that developments should examine their sustainability more seriously to ensure that they do not compromise the ability of future generations to meet their own needs. This has also attributes to the sustainability demand of ceramic technologies. In the last decades a wide variety of ceramics developments have been brought to the markets, ranging from human implants to thermal barrier coatings in fossil power plants. There are innovative developments which should enter the market within the next years like solid oxide fuel cells or separation membranes for gas and liquids. Further ahead there will be ceramics with self-adapting, self-healing and multifunctional features to generate novel applications to save energy and to reduce carbon footprints across the entire value creation process of energy, industry, transportation and manufacturing.

  17. Ceramic Technologies for Sustainability: Perspectives from Siemens Corporate Technology

    International Nuclear Information System (INIS)

    Climate change, environmental care, energy efficiency, scarcity of resources, population growth, demographic change, urbanization and globalization are the most pressing questions in the coming century. They will have an effect on all regions and groups of global society. Effective solutions will require immediate, efficient and concerted activities in all areas at the social, economic and environmental level. Since the 1980s it has been understood that developments should examine their sustainability more seriously to ensure that they do not compromise the ability of future generations to meet their own needs. This has also attributes to the sustainability demand of ceramic technologies. In the last decades a wide variety of ceramics developments have been brought to the markets, ranging from human implants to thermal barrier coatings in fossil power plants. There are innovative developments which should enter the market within the next years like solid oxide fuel cells or separation membranes for gas and liquids. Further ahead there will be ceramics with self-adapting, self-healing and multifunctional features to generate novel applications to save energy and to reduce carbon footprints across the entire value creation process of energy, industry, transportation and manufacturing.

  18. Alumina ceramics prepared with new pore-forming agents

    Directory of Open Access Journals (Sweden)

    Zuzana Živcová

    2008-06-01

    Full Text Available Porous ceramics have a wide range of applications at all length scales, ranging from fi ltration membranes and catalyst supports to biomaterials (scaffolds for bone ingrowths and thermally or acoustically insulating bulk materials or coating layers. Organic pore-forming agents (PFAs of biological origin can be used to control porosity, pore size and pore shape. This work concerns the characterization and testing of several less common pore-forming agents (lycopodium, coffee, fl our and semolina, poppy seed, which are of potential interest from the viewpoint of size, shape or availability. The performance of these new PFAs is compared to that of starch, which has become a rather popular PFA for ceramics during the last decade. The PFAs investigated in this work are in the size range from 5 μm (rice starch to approximately 1 mm (poppy seed, all with more or less isometric shape. The burnout behavior of PFAs is studied by thermal analysis, i.e. thermogravimetry and differential thermal analysis. For the preparation of porous alumina ceramics from alumina suspensions containing PFAs traditional slip casting (into plaster molds and starch consolidation casting (using metal molds are used in this work. The resulting microstructures are investigated using optical microscopy, combined with image analysis, as well as other methods (Archimedes method of double-weighing in water, mercury intrusion porosimetry.

  19. Enabling Exploration Through Docking Standards

    Science.gov (United States)

    Hatfield, Caris A.

    2012-01-01

    Human exploration missions beyond low earth orbit will likely require international cooperation in order to leverage limited resources. International standards can help enable cooperative missions by providing well understood, predefined interfaces allowing compatibility between unique spacecraft and systems. The International Space Station (ISS) partnership has developed a publicly available International Docking System Standard (IDSS) that provides a solution to one of these key interfaces by defining a common docking interface. The docking interface provides a way for even dissimilar spacecraft to dock for exchange of crew and cargo, as well as enabling the assembly of large space systems. This paper provides an overview of the key attributes of the IDSS, an overview of the NASA Docking System (NDS), and the plans for updating the ISS with IDSS compatible interfaces. The NDS provides a state of the art, low impact docking system that will initially be made available to commercial crew and cargo providers. The ISS will be used to demonstrate the operational utility of the IDSS interface as a foundational technology for cooperative exploration.

  20. Transport properties of HTSC ceramics

    International Nuclear Information System (INIS)

    By the combined influence of high pressures and silver doping it is possible to increase the critical current of yttrium metal-ceramics up to 104A/cm2 at T=77 K2 in a self-magnetic field; at T=4,2 K currents up to 2 103 A/cm2 have been realized in a 3 T field. The ideas being developed of metal-ceramics as a Josephson medium together with pressure as a perfectly operated parameter in the experiment were found to be extremely effective in the analysis of the results. 90 refs.; 5 figs

  1. Ceramic components for MHD electrode

    Science.gov (United States)

    Marchant, D.D.

    A ceramic component which exhibits electrical conductivity down to near room temperatures has the formula: Hf/sub x/In/sub y/A/sub z/O/sub 2/ where x = 0.1 to 0.4, y = 0.3 to 0.6, z = 0.1 to 0.4 and A is a lanthanide rare earth or yttrium. The component is suitable for use in the fabrication of MHD electrodes or as the current leadout portion of a composite electrode with other ceramic components.

  2. Elaboration and characterization of hybrid lithium-ion conducting membranes for aqueous lithium-air batteries

    OpenAIRE

    Lancel, Gilles

    2016-01-01

    Aqueous lithium-air batteries could be a revolution in energy storage, but the main limitation is the use of a thick glass-ceramic lithium ionic conductor to isolate the metallic lithium from the aqueous electrolyte. This makes the system more fragile, limits its cyclability and increases ohmic resistance. The aim of this work is to replace the glass-ceramic by a hybrid membrane made by electrospinning, which combines water tightness, flexibility and lithium-ions conductivity. The ionic condu...

  3. Support Services for Ceramic Fiber-Ceramic Matrix Composites

    Energy Technology Data Exchange (ETDEWEB)

    Hurley, J.P.

    2000-06-06

    built to simulate the Kellogg entrained-bed gasifier in use at the Southern Company Services Wilsonville facility, but at 1/10 of the firing rate. At the exit of the unit is a large candle filter vessel typically operated at approximately 1000 F (540 C) in which coupons of materials can be inserted to test their resistance to gasifier ash and gas corrosion. The system also has ports for testing of hydrogen separation membranes that are suitably contained in a pressure housing. In addition, NETL is operating the combustion and environmental research facility (CERF). In recent years, the 0.5 MMBtu/hr (0.5 x 10{sup 6} kJ/hr) CERF has served as a host for exposure of over 60 ceramic and alloy samples at ambient pressure as well as at 200 psig (for tubes). Samples have been inserted in five locations covering 1700-2600 F (930-1430 C), with exposures exceeding 1000 hours. In the present program, the higher priority metals are to be tested at 1500-1600 F (820-870 C) in one CERF location and near 1800-2000 F (980-1090 C) at other locations to compare results with those from the EERC tests.

  4. DUAL PHASE MEMBRANE FOR HIGH TEMPERATURE CO2 SEPARATION

    Energy Technology Data Exchange (ETDEWEB)

    Jerry Y.S. Lin

    2002-12-01

    This project is aimed at synthesis of a new inorganic dual-phase carbonate membrane for high temperature CO{sub 2} separation. Metal-carbonate dual-phase membranes were prepared by the direct infiltration method and the synthesis conditions were optimized. The dual-phase membranes are gas-tight with helium permeance about six orders of magnitude lower than that for the metal support. Efforts were made to test seals for permeation and separation experiments for dual-phase membrane at the intermediate temperature range (about 500 C) under oxidizing atmosphere. An effective new permeation cell with a metal seal was designed, fabricated and tested. The permeation setup provided leak-free sealing for the dual-phase membranes under the desired operation conditions. Though the reliable data showing high permeance for carbon dioxide with oxygen for the prepared metal-carbonate dual phase membrane has not been measured, the research efforts in improving membrane synthesis and setting up a new permeation cell with suitable seal have made it closer for one to demonstrate good dual-phase membranes for high temperature carbon dioxide separation. Research efforts were also directed towards preparation of a new ceramic-carbonate dual-phase membrane. Porous lanthanum cobaltite (LC) perovskite type oxide ceramic support with oxidation resistance better than the metal support and high electronic conductivity (1300-1500 S/cm in 400-600 C), was prepared and studied as an alternative support for the dual-phase carbonate membranes. The LC powder was found not reactive with the carbonate at 600 C. The porous LC disks have helium permeance and pore diameter smaller than the metal support but larger than the common {alpha}-alumina support. These results show promise to use the LC support for preparation of oxidation resistant dual-phase carbonate membranes.

  5. Live cell imaging of membrane / cytoskeleton interactions and membrane topology

    Science.gov (United States)

    Chierico, Luca; Joseph, Adrian S.; Lewis, Andrew L.; Battaglia, Giuseppe

    2014-09-01

    We elucidate the interaction between actin and specific membrane components, using real time live cell imaging, by delivering probes that enable access to components, that cannot be accessed genetically. We initially investigated the close interplay between Phosphatidylinositol 4,5-bisphosphate (PIP2) and the F-actin network. We show that, during the early stage of cell adhesion, PIP2 forms domains within the filopodia membrane. We studied these domains alongside cell spreading and observed that these very closely follow the actin tread-milling. We show that this mechanism is associated with an active transport of PIP2 rich organelles from the cell perinuclear area to the edge, along actin fibers. Finally, mapping other phospholipids and membrane components we observed that the PIP2 domains formation is correlated with sphingosine and cholesterol rafts.

  6. Efficient preparation and analysis of membrane and membrane protein systems.

    Science.gov (United States)

    Javanainen, Matti; Martinez-Seara, Hector

    2016-10-01

    Molecular dynamics (MD) simulations have become a highly important technique to consider lipid membrane systems, and quite often they provide considerable added value to laboratory experiments. Rapid development of both software and hardware has enabled the increase of time and size scales reachable by MD simulations to match those attainable by several accurate experimental techniques. However, until recently, the quality and maturity of software tools available for building membrane models for simulations as well as analyzing the results of these simulations have seriously lagged behind. Here, we discuss the recent developments of such tools from the end-users' point of view. In particular, we review the software that can be employed to build lipid bilayers and other related structures with or without embedded membrane proteins to be employed in MD simulations. Additionally, we provide a brief critical insight into force fields and MD packages commonly used for membrane and membrane protein simulations. Finally, we list analysis tools that can be used to study the properties of membrane and membrane protein systems. In all these points we comment on the respective compatibility of the covered tools. We also share our opinion on the current state of the available software. We briefly discuss the most commonly employed tools and platforms on which new software can be built. We conclude the review by providing a few ideas and guidelines on how the development of tools can be further boosted to catch up with the rapid pace at which the field of membrane simulation progresses. This includes improving the compatibility between software tools and promoting the openness of the codes on which these applications rely. This article is part of a Special Issue entitled: Biosimulations edited by Ilpo Vattulainen and Tomasz Róg. PMID:26947184

  7. Context-Enabled Business Intelligence

    Energy Technology Data Exchange (ETDEWEB)

    Troy Hiltbrand

    2012-04-01

    To truly understand context and apply it in business intelligence, it is vital to understand what context is and how it can be applied in addressing organizational needs. Context describes the facets of the environment that impact the way that end users interact with the system. Context includes aspects of location, chronology, access method, demographics, social influence/ relationships, end-user attitude/ emotional state, behavior/ past behavior, and presence. To be successful in making Business Intelligence content enabled, it is important to be able to capture the context of use user. With advances in technology, there are a number of ways in which this user based information can be gathered and exposed to enhance the overall end user experience.

  8. Electrospinning of ceramic nanofibers

    Science.gov (United States)

    Eick, Benjamin M.

    Silicon Carbide (SiC) nanofibers of diameters as low as 20 nm are fabricated. The fibers were produced through the electrostatic spinning of the preceramic poly(carbomethylsilane) with pyrolysis to ceramic. A new technique was used where the preceramic was blended with polystyrene (PS) and, subsequent to electrospinning, was exposed to UV to crosslink the PS and prevent fibers flowing during pyrolysis. Electrospun SiC fibers were characterized by FTIR, TGA-DTA, SEM, TEM, XRD, and SAED. Fibers were shown to be polycrystalline and nanograined with alpha-SiC 15R polytype being dominant, where commercial fiber production methods form beta-SiC 3C. Pyrolysis of the bulk polymer blend to SiC produced alpha-SiC 15R as the dominant polytype with larger grains showing that electrospinning nanofibers affects resultant crystallinity. Fibers produced were shown to have a core-shell structure of an oxide scale that was variable by pyrolysis conditions. Metal oxide powders (chromium oxide, cobalt oxide, iron oxide, silicon oxide, tantalum oxide, titanium oxide, tungsten oxide, vanadium oxide, and zirconium oxide), were converted to metal carbide powders and metal nitride powders by the process of carbothermal reduction (CTR). Synthetic pitch was explored as an alternative to graphite which is a common carbon source for CTR. It was shown via characterization with XRD that pitch performs as well and in some cases better than graphite and is therefore a viable alternative in CTR. Conversion of metal oxide powders with pitch led to conversion of sol-gel based metal oxide nanofibers produced by electrospinning. Pitch was soluble in the solutions xv that were electrospun allowing for intimate contact between the sol-gel and the carbon source for CTR. This method became a two step processing method to produce metal carbide and nitride nanofibers: first electrospin sol-gel based metal oxide nanofibers and subsequently pyrolize them in the manner of CTR to transform them. Results indicate

  9. Novel disk modules for membrane separation processes

    International Nuclear Information System (INIS)

    The reverse osmosis (RO) system at the Effluent Treatment Facility (ETF) at the Savannah River Site, Aiken, South Carolina has experienced fouling from trace quantities of inorganics (Al, Fe, and Si) and l.E5-l.E7/ml bacteria. The bacteria are primarily produced in an upstream Hg-removal resin bed/activated carbon bed process. The bacteria adhere to the colloidal inorganics that are in the membrane feed at their solubility limits (having been precipitated and removed upstream by a ceramic microfilter system). The resulting bacterial/inorganic foulant adheres to the membrane surface and results in high feed pressures and poor salt rejection. The feed pressure increases because the membrane system at the ETF is designed to produce a constant rate of treated water, or permeate. This is accomplished by increasing the membrane feed pressure whenever permeate flow drops. These performance losses have been attributed to bacteria present in the feed, and several potential solutions have been proposed and demonstrated here at the Savannah River Technology Center (SRTC). Advanced hybrid plate-and-frame modules have been developed that increase the applicability of membrane systems by using hydrodynamics rather than pretreatment to prevent membrane fouling

  10. Novel disk modules for membrane separation processes

    Energy Technology Data Exchange (ETDEWEB)

    Siler, J.L.

    1993-12-06

    The reverse osmosis (RO) system at the Effluent Treatment Facility (ETF) at the Savannah River Site, Aiken, South Carolina has experienced fouling from trace quantities of inorganics (Al, Fe, and Si) and l.E5-l.E7/ml bacteria. The bacteria are primarily produced in an upstream Hg-removal resin bed/activated carbon bed process. The bacteria adhere to the colloidal inorganics that are in the membrane feed at their solubility limits (having been precipitated and removed upstream by a ceramic microfilter system). The resulting bacterial/inorganic foulant adheres to the membrane surface and results in high feed pressures and poor salt rejection. The feed pressure increases because the membrane system at the ETF is designed to produce a constant rate of treated water, or permeate. This is accomplished by increasing the membrane feed pressure whenever permeate flow drops. These performance losses have been attributed to bacteria present in the feed, and several potential solutions have been proposed and demonstrated here at the Savannah River Technology Center (SRTC). Advanced hybrid plate-and-frame modules have been developed that increase the applicability of membrane systems by using hydrodynamics rather than pretreatment to prevent membrane fouling.

  11. High temperature ceramics for automobile gas turbines. Part 2: Development of ceramic components

    Science.gov (United States)

    Walzer, P.; Koehler, M.; Rottenkolber, P.

    1978-01-01

    The development of ceramic components for automobile gas turbine engines is described with attention given to the steady and unsteady thermal conditions the ceramics will experience, and their anti-corrosion and strain-resistant properties. The ceramics considered for use in the automobile turbines include hot-pressed Si3N4, reaction-sintered, isostatically pressed Si3N4, hot-pressed SiC, reaction-bonded SiC, and glass ceramics. Attention is given to the stress analysis of ceramic structures and the state of the art of ceramic structural technology is reviewed, emphasizing the use of ceramics for combustion chambers and ceramic shrouded turbomachinery (a fully ceramic impeller).

  12. Separators - Technology review: Ceramic based separators for secondary batteries

    Energy Technology Data Exchange (ETDEWEB)

    Nestler, Tina; Schmid, Robert; Münchgesang, Wolfram; Bazhenov, Vasilii; Meyer, Dirk C. [Technische Universität Bergakademie Freiberg, Institut für Experimentelle Physik, Leipziger Str. 23, 09596 Freiberg (Germany); Schilm, Jochen [Fraunhofer-Institut für Keramische Technologien und Systeme IKTS, Winterbergstraße 28, 01277 Dresden (Germany); Leisegang, Tilmann [Fraunhofer-Technologiezentrum Halbleitermaterialien THM, Am St.-Niclas-Schacht 13, 09599 Freiberg (Germany)

    2014-06-16

    Besides a continuous increase of the worldwide use of electricity, the electric energy storage technology market is a growing sector. At the latest since the German energy transition ('Energiewende') was announced, technological solutions for the storage of renewable energy have been intensively studied. Storage technologies in various forms are commercially available. A widespread technology is the electrochemical cell. Here the cost per kWh, e. g. determined by energy density, production process and cycle life, is of main interest. Commonly, an electrochemical cell consists of an anode and a cathode that are separated by an ion permeable or ion conductive membrane - the separator - as one of the main components. Many applications use polymeric separators whose pores are filled with liquid electrolyte, providing high power densities. However, problems arise from different failure mechanisms during cell operation, which can affect the integrity and functionality of these separators. In the case of excessive heating or mechanical damage, the polymeric separators become an incalculable security risk. Furthermore, the growth of metallic dendrites between the electrodes leads to unwanted short circuits. In order to minimize these risks, temperature stable and non-flammable ceramic particles can be added, forming so-called composite separators. Full ceramic separators, in turn, are currently commercially used only for high-temperature operation systems, due to their comparably low ion conductivity at room temperature. However, as security and lifetime demands increase, these materials turn into focus also for future room temperature applications. Hence, growing research effort is being spent on the improvement of the ion conductivity of these ceramic solid electrolyte materials, acting as separator and electrolyte at the same time. Starting with a short overview of available separator technologies and the separator market, this review focuses on ceramic

  13. Separators - Technology review: Ceramic based separators for secondary batteries

    International Nuclear Information System (INIS)

    Besides a continuous increase of the worldwide use of electricity, the electric energy storage technology market is a growing sector. At the latest since the German energy transition ('Energiewende') was announced, technological solutions for the storage of renewable energy have been intensively studied. Storage technologies in various forms are commercially available. A widespread technology is the electrochemical cell. Here the cost per kWh, e. g. determined by energy density, production process and cycle life, is of main interest. Commonly, an electrochemical cell consists of an anode and a cathode that are separated by an ion permeable or ion conductive membrane - the separator - as one of the main components. Many applications use polymeric separators whose pores are filled with liquid electrolyte, providing high power densities. However, problems arise from different failure mechanisms during cell operation, which can affect the integrity and functionality of these separators. In the case of excessive heating or mechanical damage, the polymeric separators become an incalculable security risk. Furthermore, the growth of metallic dendrites between the electrodes leads to unwanted short circuits. In order to minimize these risks, temperature stable and non-flammable ceramic particles can be added, forming so-called composite separators. Full ceramic separators, in turn, are currently commercially used only for high-temperature operation systems, due to their comparably low ion conductivity at room temperature. However, as security and lifetime demands increase, these materials turn into focus also for future room temperature applications. Hence, growing research effort is being spent on the improvement of the ion conductivity of these ceramic solid electrolyte materials, acting as separator and electrolyte at the same time. Starting with a short overview of available separator technologies and the separator market, this review focuses on ceramic-based separators

  14. Correlation between metal-ceramic bond strength and coefficient of linear thermal expansion difference

    Directory of Open Access Journals (Sweden)

    Stella Crosara Lopes

    2009-04-01

    Full Text Available The purpose of this study was to evaluate the metal-ceramic bond strength (MCBS of 6 metal-ceramic pairs (2 Ni-Cr alloys and 1 Pd-Ag alloy with 2 dental ceramics and correlate the MCBS values with the differences between the coefficients of linear thermal expansion (CTEs of the metals and ceramics. Verabond (VB Ni-Cr-Be alloy, Verabond II (VB2, Ni-Cr alloy, Pors-on 4 (P, Pd-Ag alloy, and IPS (I and Duceram (D ceramics were used for the MCBS test and dilatometric test. Forty-eight ceramic rings were built around metallic rods (3.0 mm in diameter and 70.0 mm in length made from the evaluated alloys. The rods were subsequently embedded in gypsum cast in order to perform a tensile load test, which enabled calculating the CMBS. Five specimens (2.0 mm in diameter and 12.0 mm in length of each material were made for the dilatometric test. The chromel-alumel thermocouple required for the test was welded into the metal test specimens and inserted into the ceramics. ANOVA and Tukey's test revealed significant differences (p=0.01 for the MCBS test results (MPa, with PI showing higher MCBS (67.72 than the other pairs, which did not present any significant differences. The CTE (10-6 oC-1 differences were: VBI (0.54, VBD (1.33, VB2I (-0.14, VB2D (0.63, PI (1.84 and PD (2.62. Pearson's correlation test (r=0.17 was performed to evaluate of correlation between MCBS and CTE differences. Within the limitations of this study and based on the obtained results, there was no correlation between MCBS and CTE differences for the evaluated metal-ceramic pairs.

  15. Development of a novel ceramic microchannel reactor for methane steam reforming

    Science.gov (United States)

    Murphy, Danielle M.

    Microchannel heat exchanger and reactor technology has recently gained interest as an innovative way to improve heat-exchanger efficiency, reduce size and weight, and utilize thermal management capabilities to improve conversion, yield, selectivity, and catalyst life. Among many other possible applications, this technology is suitable for advanced recuperated engines, oxy-fired combustion processes for oxygen separation, gas-cooled nuclear reactors, recuperative heat exchanger and reformer units for solid oxide fuel cell systems, and chemical processing. This work presents the design, fabrication, and performance of novel ceramic microchannel reactors in heat-exchanger and fuel-reforming applications. Although most microchannel devices are made of metal materials, ceramics offer an alternative which enables significantly higher operating temperatures, improved tolerance to harsh chemical environments, and improved adherence of ceramic-based catalyst washcoats. Significant cost savings in materials and manufacturing methods for high-volume manufacturing can also be achieved. High-temperature performance of the ceramic microchannel reactor is measured through non-reactive heat-exchanger experiments within a dedicated test stand. Heat-exchanger effectiveness of up to 88% is experimentally established. After coating catalyst material over half of the reactor layers, use of the ceramic microchannel reactor in methane fuel-processing applications is demonstrated. As a fuel reformer, the ceramic microchannel reactor achieves process intensification by combining heat-exchanger and catalytic-reactor functions to produce syngas. Gas hourly space velocities (GHSV) up to 50,000 hr-1 with methane conversion higher than 85% are achieved. A complete computational fluid dynamics (CFD) model, as well as a geometrically simplified hybrid CFD/chemical kinetics model, is used in conjunction with experimentation to examine heat transfer, fluid flow, and chemical kinetics within the

  16. Natural Radioactivity in Ceramic Materials

    International Nuclear Information System (INIS)

    Ceramics are one of the most important types of the industrial building materials. The raw materials of the ceramic are made of a mixture of clay, feldspar, silica, talc kaolin minerals together with zirconium silicates (ZrSiO4).The ceramic raw materials and the final products contain naturally occurring radionuclide mainly U-238 and, Th-232 series, and the radioactive isotope of potassium K-40. Six raw ceramic samples were obtained from the Aracemco Company at Egypt together with a floor tile sample (final product) for measuring radioactive concentration levels., The activity of the naturally U-238, Th-232, and K-40 were determined as (Bq/kg) using gamma spectroscopy (Hyperactive pure germanium detector). Concentration of U and Th were determined in (ppm) using spectrophotometer technique by Arsenazo 111 and Piridy l-Azo -Resorcinol (PAR) indicators. Sequential extraction tests were carried out in order to determine the quantity of the radionuclide associated with various fractions as exchangeable, carbonate, acid soluble and in the residue. The results evaluated were compared to the associated activity indices (AI) that were defined by former USSR and West Germany

  17. Radiation Effects in Nuclear Ceramics

    Directory of Open Access Journals (Sweden)

    L. Thomé

    2012-01-01

    Full Text Available Due to outstanding physicochemical properties, ceramics are key engineering materials in many industrial domains. The evaluation of the damage created in ceramics employed in radiative media is a challenging problem for electronic, space, and nuclear industries. In this latter field, ceramics can be used as immobilization forms for radioactive wastes, inert fuel matrices for actinide transmutation, cladding materials for gas-cooled fission reactors, and structural components for fusion reactors. Information on the radiation stability of nuclear materials may be obtained by simulating the different types of interactions involved during the slowing down of energetic particles with ion beams delivered by various types of accelerators. This paper presents a review of the radiation effects occurring in nuclear ceramics, with an emphasis on recent results concerning the damage accumulation processes. Energetic ions in the KeV-GeV range are used to explore the nuclear collision (at low energy and electronic excitation (at high energy regimes. The recovery by electronic excitation of the damage created by ballistic collisions (SHIBIEC process is also addressed.

  18. Properties Research of Ceramic Layer

    Directory of Open Access Journals (Sweden)

    Z. Żółkiewicz

    2012-12-01

    Full Text Available In the method of full mould the polystyrene model, which fills the mould cavity in the course of filling by the liquid metal is subjected tothe influence of high temperature and passes from the solid, through the liquid, to the gaseous state. During this process solid and gaseousproducts of thermal decomposition of polystyrene patterns occur. The kinetics of this process is significantly influenced by the gasificationtemperature, density and mass of the polystyrene patterns. One of the basic parameters is the amount and rate of gas from the polystyrenemodel during its thermal decomposition. Specific properties of ceramic layer used for lost foam castings are required. To ensure optimalprocess flow of metal in the form proper permeability of the ceramic layer is needed.To ensure optimal conditions for technological casting method EPS patterns are tested and determined are the technological parametersand physical-chemical process in: material properties of the pattern, properties of the ceramic layer applied to the pattern, pattern gasification kinetics pouring processIn the course of the research the characteristics of polystyrene and ceramic layer were determined.

  19. Thermal shock resistant ceramic insulator

    International Nuclear Information System (INIS)

    A specification is given for thermal shock resistant cermet insulators which contain 0.1 to 20 volume % metal present as a dispersed phase. They are prepared by (a) providing a first solid phase mixture of a ceramic powder and a metal precursor; (b) heating the first solid phase mixture above the minimum decomposition temperature of the metal precursor for no longer than 30 minutes and to a temperature sufficiently above the decomposition temperature to cause the selective decomposition of the metal precursor to the metal to provide a second solid phase mixture comprising particles of ceramic having discrete metal particles adhering to their surfaces, the metal particles having a mean diameter no more than 1/2 the mean diameter of the ceramic particles, and (c) densifying the second solid phase mixture to provide the desired cermet insulator. Examples of the ceramics include BN, B4C, ZrO2, WO3, BeO, Y2O3, TaO, the lanthanide oxides, the oxides of uranium, the oxides of thorium, the oxides of niobium. Examples of the metal precursor include TaHsub(0.5), UH3, ZrH2, ThH2, W(CO)6, ReCl3, WO3 MoO3. (author)

  20. Superplastic forming of ceramic insulation

    Science.gov (United States)

    Nieh, T. G.; Wittenauer, J. P.; Wadsworth, J.

    1992-01-01

    Superplasticity has been demonstrated in many fine-grained structural ceramics and ceramic composites, including yttria-stabilized tetragonal zirconia polycrystal (YTZP), alumina, and Al2O3-reinforced zirconia (Al2O3/YTZ) duplex composites and SiC-reinforced Si3N4. These superplastic ceramics obviously offer the potential benefit of forming net shape or near net shape parts. This could be particularly useful for forming complicated shapes that are difficult to achieve using conventional forming techniques, or require elaborate, subsequent machining. In the present study, we successfully demonstrated the following: (1) superplastic 3Y-TXP and 20 percent Al2O3/YTZ composite have for the first time been successfully deformed into hemispherical caps via a biaxial gas-pressure forming technique; (2) no experimental difficulty was encountered in applying the required gas pressures and temperatures to achieve the results, thus, it is certain that higher rates of deformation than those presented in this study will be possible by using the current test apparatus at higher temperatures and pressures; and (3) an analytical model incorporating material parameters, such as variations during forming in the strain rate sensitivity exponent and grain growth-induced strain hardening, is needed to model accurately and therefore precisely control the biaxial gas-pressure forming of superplastic ceramics. Based on the results of this study, we propose to fabricate zirconia insulation tubes by superplastic extrusion of zirconia polycrystal. This would not only reduce the cost, but also improve the reliability of the tube products.