Download or read book An Attrition resistant Zinc Titanate Sorbent for Sulfur Technical Report December 1 1992 February 28 1993 written by and published by . This book was released on 1993 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the continuing search for good sorbent materials to remove sulfur from hot, coal-derived gases, zinc titanate sorbents have shown great promise. The objective of this project is to extend the work of prior investigators to obtain improvements in the compressive strength and, therefore, the cycle life of these sorbents without a significant loss in chemical reactivity. During the second quarter, parametric data were obtained on the percent porosity, crush strength, and chemical reactivity for a sorbent composition of 75% Zn2TiO4 - 25% TiO2. This material was sintered at temperatures ranging from 700 to 1100°C. Although more extensive reactivity tests are still needed, results to date indicate that the best combination of properties is obtained with a sintering temperature of 800 or 850°C. Also planned for the next quarter are evaluations of other sorbent formulations.
Download or read book Goethe Studien written by and published by . This book was released on 1943 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Research Abstracts written by and published by . This book was released on 1993 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Attrition resistant Zinc Titanate Sorbent for Sulfur Final Technical Report September 1 1992 August 31 1993 written by and published by . This book was released on 1993 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the continuing search for good sorbent materials to remove sulfur for hot, coal-derived gases, zinc titanate sorbents have shown great promise. The objective of this project was to extend the work of prior investigators by developing improvements in the compressive strength and, therefore, the cycle life of these sorbents while maintaining good chemical reactivity. Fifteen formulations were prepared and evaluated. The best properties were obtained by blending relatively course (two micron) ZnO and TiO2 powders to obtain a composition of 50%Zn2TiO4-50%TiO2. When sintered at 1000°C, it had a compressive strength of 28 MPa or 147 N/mm, which is four times higher than values obtained by prior investigators. It also performed well in thermogravimetric analysis measurements of reactivity, both in screening tests and in simulated coal gas.
Download or read book An Attrition resistant Zinc Titanate Sorbent for Sulfur Technical Report September 1 Through November 30 1993 written by and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Attrition resistant Zinc Titanate Sorbent for Sulfur Quarterly Technical Report March 1 1993 May 31 1993 written by and published by . This book was released on 1993 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the continuing search for good sorbent materials to remove sulfur from hot, coal-derived gases, zinc titanate sorbents have shown great promise. The objective of this project is to extend the work of prior investigators by developing improvements in the compressive strength and, therefore, the cycle life of these sorbents without a significant loss in chemical reactivity. During the third quarter, the preparation and properties of sorbents with a nominal composition of 50% Zn2TiO4 and 50% TiO2 were studied. In differential thermogravimetric tests of reactivity, specimens sintered at 850 and 900°C both gave two identical sulfidation-regeneration cycles. Specimens sintered at lower temperatures showed evidence of degradation during the second cycle. Materials of this composition had lower crush strengths than for the composition 75% Zn2TiO4 -- 25% TiO2 reported earlier, but higher values than reported by other investigators. Future work will include the preparation and properties of a lot of material with a coarser structure and larger pores, and microscopic studies on all three lots of material.
Download or read book Government reports annual index written by and published by . This book was released on 199? with total page 1190 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Attrition resistant Zinc Titanate Sorbent for Sulfur Technical Report 1 March 31 May 1994 written by and published by . This book was released on 1994 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the continuing search for good sorbent materials to remove sulfur from hot, coal-derived gases, zinc titanate sorbents have shown great promise. The objective of this project is to extend the effort started last year on sorbents with little or no loss in chemical reactivity. The principle is to contain Zn2TiO4 in a structural matrix of excess TiO2. Progress on several tasks was made during the third quarter. The new fixed bed apparatus at SIUC was made operational, and experiments in it have started. The feasibility of using turbine exhaust gas diluted with N2 for sorbent regeneration was demonstrated through experiments at both SIUC and RTI. The third of four ten-cycle tests was completed at RTI. It was a fixed bed test on one to two promising formulations developed last year. The results followed the pattern of the fluidized bed tests completed earlier in that the chemical reactivity was good, except for the first few cycles. Lastly the undergraduate student design project on hot gas desulfurization hardware was completed this quarter.
Download or read book An Attrition resistant Zinc Titanate Sorbent for Sulfur Quarterly Report September 1 November 30 1993 written by and published by . This book was released on 1994 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the continuing search for good sorbent materials to remove sulfur from hot, coal-derived gases, zinc titanate sorbents have shown great promise. The objective of this project is to extend the effort started last year on increasing the strength and durability of zinc titanate sorbents with little or no loss in chemical reactivity. The principle is to contain Zn2TiO4 in a structural matrix of excess TiO2. A fluidized bed test was completed this quarter on the first of two promising sorbent formulations. The chemical reactivity in the form of breakthrough curves became progressively better over ten sulfidation-regeneration cycles. While the chemical reactivity was very good, the attrition resistance was only fair, due presumably to the conversion of Zn2TiO4 to ZnTiO3 during cycling. The next formulation to be tested is expected to be better in attrition resistance.
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1993 with total page 1088 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Attrition Resistant Zinc Titanate containing Reduced Sulfur Sorbents written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The disclosure is directed to sorbent compositions for removing reduced sulfur species (e.g., H.sub. 2 S, COS and CS.sub. 2) a feed stream. The sorbent is formed from a multi-phase composition including a zinc titanate phase and a zinc oxide-aluminate phase. The sorbent composition is substantially free of unreacted alumina.
Download or read book Attrition Resistant Zinc Titanate containing Reduced Sulfur Sorbents and Methods of Use Thereof written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Reduced sulfur gas species (e.g., H.sub. 2S, COS and CS.sub. 2) are removed from a gas stream by compositions wherein a zinc titanate ingredient is associated with a metal oxide-aluminate phase material in the same particle species. Nonlimiting examples of metal oxides comprising the compositions include magnesium oxide, zinc oxide, calcium oxide, nickel oxide, etc.
Download or read book Composition Modification of Zinc Titanate Sorbents for Hot Gas Desulfurization Technical Report March 1 May 31 1995 written by and published by . This book was released on 1995 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: For new coal gasification systems, zinc titanate sorbents are being developed to remove sulfur from the hot product gas prior to its use in combined cycle turbines and high temperature fuel cells. Although most of the properties of these sorbents are very attractive, there are still concerns about durability over many sulfidation-regeneration cycles and zinc losses due to vaporization. Doping the zinc titanate with other metal ions could alleviate both concerns, which are the objectives of this project. After a screening study was completed, it was decided that Cr offered more promise as a dopant than Ni, Cu, Mg, and Al. Therefore six new sorbent formulations containing Cr were prepared, and they are now being evaluated with a series of bulk density, X-ray diffraction, crush strength and thermogravimetric analysis (TGA) measurements. Results to date suggest that, while Zn vaporization losses can be reduced with Cr additions, a penalty in chemical reactivity occurs. A fixed bed test was also completed this quarter on a Cr-containing formulation. The H2S breakthrough time was about 11 hours, and utilization of Zn in the sorbent was 60.5%.
Download or read book Composition Modification of Zinc Titanate Sorbents for Hot Gas Desulfurization Quarterly Technical Report September 1 1994 November 30 1994 written by and published by . This book was released on 1995 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: For new coal gasification systems, zinc titanate sorbents are being developed to remove sulfur from the hot product gas prior to its use in combined cycle turbines and high temperature fuel cells. Although most of the properties of these sorbents are very attractive, there are still concerns about durability over many sulfidation-regeneration cycles and zinc losses due to vaporization. Doping the zinc titanate with other metal ions could alleviate both concerns, which are the objectives of this project. During the first quarter of effort, several sorbent formulations were prepared and testing begun. The dopants presently under study are Ni, Cr, Cu, and Al. Crush strength results obtained to date show that Ni and Cu dopants have a large positive effect, while Cr gives a small improvement. Measurements were also made of sulfur capacity and sulfidation rates with a thermogravimetric analyzer. Of the three formulations, only the one containing Cr had a high sulfur capacity. X-ray measurements will be relied upon heavily to obtain an understanding of solubility effects and sulfidation mechanisms. Screening experiments will continue on the doped sorbents mentioned above next quarter, and Mg will be studied also.
Download or read book Development of Novel Copper based Sorbents for Hot Gas Cleanup Technical Report December 1 1992 February 28 1993 written by and published by . This book was released on 1993 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this investigation is to evaluate two novel copper-based sorbents (i.e. copper-chromium and copper-cerium) for their effectiveness in removing hydrogen sulfide from fuel gas in the temperature range of 650° to 850°C. New sorbent compositions from the selected Cu-Cr-O and Cu-Ce-O binary oxides were prepared and characterized by BET N2-desorption surface area measurement following various calcination/time-temperature exposures. The general trends reported last quarter (on 11 different compositions) were validated this quarter in that both binary oxides lose surface area as the amount of CuO is increased. Time-resolved sulfidation tests were conducted at 850°C using the equimolar CuO. Cr2O3 composition. The two selected binary oxides prepared in larger qauntities (for testing in a two-inch reactor) have physical properties typical of the sorbents prepared in past programs. Two multicycle desulfurization tests, conducted this quarter on the Cu-Ce-O sorbent at 850°C, using a feed gas containing 5000 ppm H2S, 10 vol % H2 and 10 vol % H2O at a space velocity (STP) of 2000 h−1, demonstrated high sulfur removal efficiency for the first one or two cycles, and a significant reduction in efficiency in the following cycles.
Download or read book Stabilization of Spent Sorbents from Coal Gasification Technical Report December 1 1992 February 28 1993 written by and published by . This book was released on 1993 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this investigation is to determine the kinetics of reactions involving partially sulfided dolomite and oxygen, which is needed for the design of the reactor system for the stabilization of sulfide-containing solid wastes from gasification of high sulfur coals. To achieve this objective, samples of partially sulfided dolomite are reacted with oxygen at a variety of operating conditions in a fluidized-bed reactor, where external diffusion limitations are avoided by using small quantities of the sorbent and maintaining a high flow rate of the reactant gas. The reacted sorbents are analyzed to determine the extent of conversion as a function of operating variables including sorbent particle size, reaction temperature and pressure, and oxygen concentration. Samples of the partially sulfided dolomite were reacted with oxygen in the fluidized-bed rector at different operating conditions. The test parameters included the effects of solid residence time, oxygen concentration, and reaction temperature. The reacted solids were analyzed to determine the extent of CaS conversion to CaSO4. The results of the tests conducted so far in the project indicate that the extent of conversion increase with increasing oxygen concentration and the solid residence time. The rate of reaction appears to be very sensitive to the reaction temperature.
Download or read book Composition Modification of Zinc Titanate Sorbents for Hot Gas Desulfurization Quarterly Report 1 December 1994 28 February 1995 written by and published by . This book was released on 1995 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: For new coal gasification systems, zinc titanate sorbents are being developed to remove sulfur from the hot product gas prior to its use in combined cycle turbines and high temperature fuel cells. Although most of the properties of these sorbents are very attractive, there are still concerns about durability over many sulfidation-regeneration cycles and zinc losses due to vaporization. Doping the zinc titanate with other metal ions could alleviate both concerns, which are the objectives of this project. A screening study was completed during the second quarter in which Ni, Cr, Cu, Mg, and Al were evaluated as dopants in zinc titanate. Measurements that were made include solubility, crush strength, and sulfidation-regeneration behavior in a thermogravimetric analyzer. A formulation containing Cr showed the most promise. It and other formulations containing Cr will be emphasized during the remainder of the year. Fixed bed experiments will start during the third quarter.
