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Ceramic Membrane Enabling Technology for Improved IGCC Efficiency, Quarterly Technical Progress Report: October 1 - December 31, 2003

Description: This quarterly technical progress report will summarize work accomplished for Phase 2 Program during the quarter October to December 2003. In task ! OTM development has led to improved strength and composite design for lower temperatures. In task 2, the yield of a large batch of OTM elements improved. In task 3, operational improvements in the lab- scale pilot reactor have reduced turn- around time and increased product purity. In task 7. IGCC economics were updated to reflect state of the art … more
Date: December 31, 2003
Creator: Prasad, Ravi
Item Type: Refine your search to only Report
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Ceramic membranes for gas separation at high temperatures. Final report

Description: Superior heat, wear, erosion, and corrosion resistance of ceramic materials have motivated the studies of processing-structure-performance interrelationships of ceramic membranes for high temperature gas separations. A literature review on pore transport mechanisms, physical structure of membranes, and module configuration of industrial membrane processes has been made to obtain a better understanding of membrane performance in gas separations. The research experience in decomposing polymer res… more
Date: March 1, 1994
Creator: Wang, C. J.
Item Type: Refine your search to only Report
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Ceramic membranes for generation of partial-oxidation products from methane

Description: The most significant cost associated with partial oxidation of methane to syngas is that of the oxygen plant. In this paper, we offer a technology, based on dense ceramic membranes, that uses air as the oxidant for methane-conversion reactions and eliminates the need for an oxygen plant. Certain ceramic materials exhibit both electronic and ionic conductivities (of particular interest is oxygen-ion conductivity). These materials transport not only oxygen ions (functioning as selective oxygen se… more
Date: May 1, 1994
Creator: Balachandran, U.; Dusek, J. T.; Sweeney, S. M.; Mieville, R. L.; Maiya, P. S.; Kleefisch, M. S. et al.
Item Type: Refine your search to only Article
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Ceramic Membranes for Hydrogen Production From Coal

Description: The preparation and performance of membranes for application to hydrogen separation from coal-derived gas is described. The membrane material investigated was dense amorphous silica deposited on a suitable support by chemical vapor deposition (CVD). Two types of support materials were pursued. One type consisted of a two-layer composite, zeolite silicalite/{alpha}-Al{sub 2}O{sub 3}, in the form of tubes approximately 0.7 cm in diameter. The other type was porous glass tubes of diameter below 0.… more
Date: April 1, 2004
Creator: Gavalas, George R.
Item Type: Refine your search to only Report
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Ceramic Membranes for Hydrogen Production From Coal

Description: 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 additio… more
Date: November 27, 2001
Creator: Gavalas, George R.
Item Type: Refine your search to only Report
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Ceramic Membranes for Hydrogen Production From Coal

Description: A technique was developed to extrude thin glass tubes from a glass-polyethersulfone-solvent (NMP) paste with a glass to polymer weight ratio of about 8. The extrudates were gelled in water and heat treated at 800-950 C to remove the polymer and sinter the particles to a dense glass structure. Subsequently, the tubes were leached in hot water to remove the soluble phase formed by phase separation during cooling. The tubes were characterized by XRD, SEM, and permeation measurements. SEM examinati… more
Date: February 23, 2004
Creator: Gavalas, George R.
Item Type: Refine your search to only Report
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Ceramic Membranes for Hydrogen Production From Coal Annual Report: 2002

Description: The objective of this project is to develop ceramic membranes for hydrogen separation from fuel gas or synthesis gas at temperatures 400-500 C. The membrane chosen for this purpose consists of a dense silica layer coated on a porous support by chemical vapor depositrion (CVD). The support used during the reporting period was zeolite silicalite grown on macroporous alumina tubes. Chemical vapor deposition was carried out using alternating exposure of the support to silicon tetrachloride (SiCl{su… more
Date: March 18, 2003
Creator: Gavalas, George R.
Item Type: Refine your search to only Report
open access

Ceramic membranes for partial oxygenation of hydrocarbon fuels to high-value-added products

Description: This report describes the design of a membrane reactor for converting methane into value added products. The design includes an outer tube of perovskite which contacts air, an inner tube of zirconium oxide which contacts methane, and a bonding layer of a mixture of zirconium oxide and perovskite.
Date: December 31, 1994
Creator: Balachandran, U.; Dusek, J.T.; Kleefisch, M.S. & Kobylinski, T.P.
Item Type: Refine your search to only Patent
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Ceramic-Metal Brazing, From Fundamentals to Applications: A Review of Sandia National Laboratories Brazing Capabilities, Needs and Opportunities

Description: The purpose of the report is to summarize discussions from a Ceramic/Metal Brazing: From Fundamentals to Applications Workshop that was held at Sandia National Laboratories in Albuquerque, NM on April 4, 2001. Brazing experts and users who bridge common areas of research, design, and manufacturing participated in the exercise. External perspectives on the general state of the science and technology for ceramics and metal brazing were given. Other discussions highlighted and critiqued Sandia's b… more
Date: May 1, 2002
Creator: Hosking, F. Michael; Stephens Jr., John J.; Glass, S. Jill; Johannes, Justine E.; Kotula, Paul G.; Lapetina, Neil A. et al.
Item Type: Refine your search to only Report
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Ceramic-Metal Composite Formation by Reactive Metal Penetration

Description: Ceramic-metal composites can be made to near-net-shape by reactive penetration of dense ceramic preforms by molten metals. Reactive metal penetration is driven by a strongly negative Gibbs energy for reaction. For Al, the general form of the reaction is (x+2) Al + (3/y) MO[sub y] yields Al[sub 2]O[sub 3] + M[sub 3/y]Al[sub x], where MO[sub y] is an oxide that is wet by molten Al. In low PO[sub 2] atmospheres and at temperatures above about 900 degrees C, molten Al reduces mullite to produce Al[… more
Date: November 1, 1996
Creator: Loehman, Ronald E.; Ewsuk, Kevin G.; Fahrenholtz, William G. & Lakshman, Bala B.
Item Type: Refine your search to only Article
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Ceramic microstructures and their elucidation by imaging, diffraction and spectroscopic methods

Description: The development and potential utilization of ceramic materials is dependent on a systematic effort involving processing, characterization and appropriate property measurements. The methods of characterization are numerous and it is important to employ the one that is appropriate to the problem both in terms of its information content and the achievable level of resolution. With the incorporation of fine probe forming capabilities in a transmission electron microscope and the development of rela… more
Date: February 1, 1992
Creator: Kirshnan, K.M.
Item Type: Refine your search to only Article
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Ceramic Microstructures and Their Elucidation by Imaging, Diffraction and Spectroscopic Methods

Description: The development and potential utilization of ceramic materials is dependent on a systematic effort involving processing, characterization and appropriate property measurements. The methods of characterization are numerous and it is important to employ the one that is appropriate to the problem both in terms of its information content and the achievable level of resolution. With the incorporation of fine probe forming capabilities in a transmission electron microscope and the development of rela… more
Date: February 1992
Creator: Kirshnan, K. M.
Item Type: Refine your search to only Article
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CERAMIC NUCLEAR FUELS IN THE SYSTEM ZrO$sub 2$-CaO-UO$sub 2$. Final Report

Description: Potential nuclear fuels in the system ZrO/sub 2/-CaO-UO/sub 2/ were investigated. Cubic fluorite-type solid solutions, as indicated by x-ray diffraction patterns, were formed by sintering CaO-stabilized ZrO/sub 2/ and U/ sub 3/O/sub 8/ compacts in either air or H/sub 2/. A continuous solid solution was found between urania and stabilized zirconia with H/sub 2/ sintering at 1750 deg C. Air sintering produced a limited region of solid solution in the stabilized zirconia portion of the system at 1… more
Date: September 1, 1962
Creator: Handwerk, J. H.; White, G. D. & Hill, D. C.
Item Type: Refine your search to only Report
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Ceramic package fabrication for YMP nuclear waste disposal

Description: The purpose of this work is to develop alternate materials/design concepts to metal barriers for the Nevada Nuclear Waste Storage Investigations Project. There is some potential that site conditions may prove to be too aggressive for successful employment of the metal alloys under current consideration or that performance assessment models will predict metal container degradation rates that are inconsistent with the goal of substantially complete containment included in the NRC regulations. In … more
Date: August 1, 1994
Creator: Wilfinger, K.
Item Type: Refine your search to only Report
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Ceramic phases for immobilization of /sup 129/I. [Sodalite and boracite]

Description: Materials for ultimate disposal of /sup 129/I have been studied. At present, iodide-sodalite, though not ideal, appears to be the best material for /sup 129/I immobilization from the aspects of ease of preparation, thermal stability, cost of materials, and leach resistance. Good consolidation of the material was achieved by sintering in air at 1000 to 1200/sup 0/C, but the iodine content was significantly below stoichiometric expectations. Hot aqueous media preferentially removed iodine, appare… more
Date: July 31, 1981
Creator: Vance, E. R.; Agrawal, D. K.; Scheetz, B. E.; Pepin, J. G.; Atkinson, S. D. & White, W. B.
Item Type: Refine your search to only Report
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Ceramic Plutonium Target Development for the MASHA Separator for the Synthesis of Element 114

Description: We are currently developing a Pu ceramic target for the MASHA mass separator. MASHA will use a Pu ceramic target capable of tolerating temperatures up to 2000 C. Reaction products will diffuse out of the target into an ion source, and transported through the separator to a position-sensitive focal-plane detector array for mass identification. Experiments on MASHA will allow us to make measurements that will cement our identification of element 114 and provide data for future experiments on chem… more
Date: June 29, 2005
Creator: Shaughnessy, D A; Wilk, P A; Moody, K J; Kenneally, J M; Wild, J F; Stoyer, M A et al.
Item Type: Refine your search to only Article
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Ceramic/polymer functionally graded material (FGM) lightweight armor system

Description: This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Functionally graded material is an enabling technology for lightweight body armor improvements. The objective was to demonstrate the ability to produce functionally graded ceramic-polymer and ceramic-metal lightweight armor materials. This objective involved two aspects. The first and key aspect was the development of graded-porosity boron-carbide cer… more
Date: December 31, 1998
Creator: Petrovic, J. J. & McClellan, K. J.
Item Type: Refine your search to only Report
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Ceramic powder compaction

Description: With the objective of developing a predictive model for ceramic powder compaction we have investigated methods for characterizing density gradients in ceramic powder compacts, reviewed and compared existing compaction models, conducted compaction experiments on a spray dried alumina powder, and conducted mechanical tests and compaction experiments on model granular materials. Die filling and particle packing, and the behavior of individual granules play an important role in determining compacti… more
Date: December 31, 1995
Creator: Glass, S. J.; Ewsuk, K. G. & Mahoney, F. M.
Item Type: Refine your search to only Article
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Ceramic powder synthesis in supercritical fluids

Description: Gas-phase processing plays an important role in the commercial production of a number of ceramic powders. These include titanium dioxide, carbon black, zinc oxide, and silicon dioxide. The total annual output of these materials is on the order of 2 million tons. The physical processes involved in gas-phase synthesis are typical of those involved in solution -phase synthesis: chemical reaction kinetics, mass transfer, nucleation, coagulation, and condensation. This report focuses on the work don… more
Date: April 1, 1996
Creator: Adkins, C. L. J.; Russick, E. M.; Cesarano, J.; Tadros, M. E. & Voigt, J. A.
Item Type: Refine your search to only Report
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Ceramic process and plant design for high-level nuclear waste immobilization

Description: In the last 3 years, significant advances in ceramic technology for high-level nuclear waste solidification have been made. Product quality in terms of leach-resistance, compositional uniformity, structural integrity, and thermal stability promises to be superior to borosilicate glass. This paper addresses the process effectiveness and preliminary designs for glass and ceramic immobilization plants. The reference two-step ceramic process utilizes fluid-bed calcination (FBC) and hot isostatic pr… more
Date: January 1, 1983
Creator: Grantham, L. F.; McKisson, R. L.; De Wames, R. E.; Guon, J.; Flintoff, J. F. & McKenzie, D. E.
Item Type: Refine your search to only Article
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Ceramic process equipment for the immobilization of plutonium

Description: Lawrence Livermore National Laboratory is developing a ceramic form for immobilizing excess US plutonium. The process used to produce the ceramic form is similar to the fabrication process used in the production of MOX fuel. In producing the ceramic form, the uranium and plutonium oxides are first milled to less than 20 microns. The milled actinide powder then goes through a mixing-blending step where the ceramic precursors, made from a mixture of calcined TiO<sub>2</sub>, Ca(OH)<sub>2</sub>, H… more
Date: July 24, 1998
Creator: Armantrout, G.; Brummond, W. & Maddux, P.
Item Type: Refine your search to only Article
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Ceramic Processing

Description: Ceramics represent a unique class of materials that are distinguished from common metals and plastics by their: (1) high hardness, stiffness, and good wear properties (i.e., abrasion resistance); (2) ability to withstand high temperatures (i.e., refractoriness); (3) chemical durability; and (4) electrical properties that allow them to be electrical insulators, semiconductors, or ionic conductors. Ceramics can be broken down into two general categories, traditional and advanced ceramics. Traditi… more
Date: November 24, 1999
Creator: EWSUK,KEVIN G.
Item Type: Refine your search to only Article
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Ceramic processing of boron nitride insulators

Description: Fuel pin simulators (FPS) are the prime elements of several test facilities at the Oak Ridge National Laboratory (ORNL). These experimental facilities are used to conduct out-of-reactor thermal-hydraulic and mechanical interaction safety tests for both light-water and breeder reactor programs. The FPS units simulate the geometry, heat flux profiles, and operational capabilities of a reactor core element under steady-state and transient conditions. They are subjected to temperatures as high as 1… more
Date: January 1, 1977
Creator: Morgan, C.S. & McCulloch, R.W.
Item Type: Refine your search to only Article
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