Composition Modification of Zinc Titanate Sorbents for Hot Gas Desulfurization. Technical Report, March 1--May 31, 1995

Composition Modification of Zinc Titanate Sorbents for Hot Gas Desulfurization. Technical Report, March 1--May 31, 1995 PDF Author:
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ISBN:
Category :
Languages : en
Pages : 17

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Book Description
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%.

Composition Modification of Zinc Titanate Sorbents for Hot Gas Desulfurization. Technical Report, March 1--May 31, 1995

Composition Modification of Zinc Titanate Sorbents for Hot Gas Desulfurization. Technical Report, March 1--May 31, 1995 PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 17

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Book Description
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%.

Composition Modification of Zinc Titanate Sorbents for Hot Gas Desulfurization. Quarterly Report, 1 December 1994--28 February 1995

Composition Modification of Zinc Titanate Sorbents for Hot Gas Desulfurization. Quarterly Report, 1 December 1994--28 February 1995 PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 16

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Book Description
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.

Composition Modification of Zinc Titanate Sorbents for Hot Gas Desulfurization

Composition Modification of Zinc Titanate Sorbents for Hot Gas Desulfurization PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Government Reports Announcements & Index

Government Reports Announcements & Index PDF Author:
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ISBN:
Category : Science
Languages : en
Pages : 676

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Composition Modification of Zinc Titanate Sorbents for Hot Gas Desulfurization. Quarterly Technical Report, September 1, 1994--November 30, 1994

Composition Modification of Zinc Titanate Sorbents for Hot Gas Desulfurization. Quarterly Technical Report, September 1, 1994--November 30, 1994 PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 18

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Book Description
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.

Composition Modification of Zinc Titanate (Zn2TiO4) Based Sorbents for Hot Coal Gas Desulfurization

Composition Modification of Zinc Titanate (Zn2TiO4) Based Sorbents for Hot Coal Gas Desulfurization PDF Author: Kimberly S. Walton
Publisher:
ISBN:
Category :
Languages : en
Pages : 142

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An Attrition-resistant Zinc Titanate Sorbent for Sulfur. Technical Report, 1 March--31 May 1994

An Attrition-resistant Zinc Titanate Sorbent for Sulfur. Technical Report, 1 March--31 May 1994 PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 19

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Book Description
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.

An Attrition-resistant Zinc Titanate Sorbent for Sulfur. [Quarterly] Technical Report, March 1, 1993--May 31, 1993

An Attrition-resistant Zinc Titanate Sorbent for Sulfur. [Quarterly] Technical Report, March 1, 1993--May 31, 1993 PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 14

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Book Description
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.

An Attrition-resistant Zinc Titanate Sorbent for Sulfur. Final Technical Report, September 1, 1992--August 31, 1993

An Attrition-resistant Zinc Titanate Sorbent for Sulfur. Final Technical Report, September 1, 1992--August 31, 1993 PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 31

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Book Description
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.

Testing and Technology Transfer for Zinc Titanate Sorbent in a Titania Matrix. Technical Report, September 1, 1995--November 30, 1995

Testing and Technology Transfer for Zinc Titanate Sorbent in a Titania Matrix. Technical Report, September 1, 1995--November 30, 1995 PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 11

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Book Description
For new coal gasification systems, zinc-based sorbents are being developed to remove sulfur from the hot product gas prior to its use in combined-cycle gas turbines and high- temperature fuel cells. In general, the properties of these sorbents are considered to be very attractive, but there are still concerns about degradation of mechanical properties and sulfur capacity over many sulfidation- regeneration cycles. It is believed that containing zinc titanate in a matrix of excess titania could solve both problems, which is the objective of this project. During this quarter, plans were made for United Catalysts, Inc. to produce two batches of the sorbent using a commercial extrusion process. A subcontract was just issued to the Research Triangle Institute for sorbent characterization and for a 50- cycle performance test designed to simulate the General Electric Company's moving-bed reactor conditions. In a parallel effort, numerous contacts were made on the technology transfer task.