Catalytic reduction of SO{sub 2} with methane over molybdenum catalyst. Quarterly technical report, September 1, 1994--November 30, 1994 [report]

T. Wiltowski
1995 unpublished
One of the primary concerns in coal utilization is the emission of sulhr compounds, especially SO2. This project deals with catalytic reduction of SO2 with methane using molybdenum sulfide catalyst supported on different activated carbons: Darco TRS, Norit ROZ-3, and an activated carbon prepared from Illinois coal IBC-110. The work conducted during this quarter has concentated on catalyst preparation and characterization along with synthesis of activated carbon from IBC-110 coal, as well as,
more » ... oal, as well as, construction of the apparatus for catalytic tests of SO2 reduction with methane. It was found that Darco TRS supported catalysts have larger surface area then the pure activated carbon, whereas the impregnation of Norit ROZ-3 did not significantly change the BET surface area. Also, the synthesis of activated carbon support from IBC-110 is in progress. U. S. DOE Patent Clearance is. NOT required prior to the publication of this document. EXECUTIVE SUMMARY The high-sulfur contents, both pyritic and organic, of Illinois's bituminous coals present significant hurdles for either effective, economical, or environmentally acceptable utilization. Therefore, it is imperative that prior to subjecting the Illinois coal to any process they either have to be physically cleaned or the sulfur compounds found in the flue gases from coal have to be adsorbed or decomposed. The choice of suitable sorbent for flue gas processing depends on many factors such as coal properties, process operating conditions, and flue gas composition. Catalytic process to decompose SO2 is alternative to adsorption techniques. The goal of this project is to evaluate the capability of molybdenum sulfide supported on an activated carbon to act as a catalyst for SO2 reduction with methane as the reactant. The specific objectives of this project are to:(l) synthesize the catalysts supported on different activated carbons, (2) determine the ability of methane to catalytically reduce sulfur dioxide at a wide range of temperatures, and (3) determine the mechanism of SO2 reduction. The work conducted during this past quarter includes catalysts preparation and characterization, preparation of activated carbon from IBC-110 coal, and construction of the apparatus for SO2 reduction with methane. Darco TRS and Norit ROZ-3 activated carbons were used as the catalyst supports. MoS2 loadings of lo%, 15%, and 20% were used in the preparation. It was found that the BET N2 surface area of Darco TRS supported catalysts increased during preparation. In contrast, the BET surface area of Norit ROZ-3 support did not change during catalyst preparation. It is suggested that the segregation phenomenon affects the surface area enhancement for Darco TRS support. The synthesis of activated carbon from IBC-110 coal is in progress. The apparatus for catalytic SO2 reduction with methane was constructed and tested. .. . . DISCLAIMER This report was prepared a s an account of work sponsored by an agency of t h e United States Government. Neither t h e United States Government nor any agency thereof, nor any of their employees, make any warranty, express or implied, or assumes any legal liability or responsibility for t h e accuracy, completeness, or usefulness of any information, apparatus" product, or process disclosed, or represents that I -1 9 large to go through the 60 mesh, so the remaining coal was run through a ball mill at 45 second intervals and then sifted until the entire lot could be sized. This preparation is in progress. CONCLUSIONS AND RECOMMENDATIONS 1. The apparatus for catalytic reduction of SO, with methane was constructed and tested. 2. Six molybdenum sulfide catalysts having three different loadings (lo%, 15%, and 20%) supported on Darco TRS and Norit ROZ-3 activated carbons were synthesized and characterized. 3. The surface area of Darco TRS supported MoS, catalysts increased during impregnation. In contrast, the surface area of Norit ROZ-3 supported catalysts remains essentially constant. Both catalyst supports have basic differences in average pore size diameter. 4. Surface area increase for Darco TRS catalyst support'during preparation may be attributed to the surface segregation of MoS, sublayer. 5. Synthesis of activated carbon support fiom IBC-110 coal is in progress.
doi:10.2172/29422 fatcat:u6kutzvmjjdn5nyqxio53pppdu