DEVELOPMENT OF IMPROVED CATALYSTS FOR THE SELECTIVE CATALYTIC REDUCTION OF NITROGEN OXIDES WITH HYDROCARBONS

Akyurtlu, Dr. Ates ; Akyurtlu, Dr. Jale F.

Holditch-Reservoir Technologies Consulting Services (United States)

关键词: Natural Gas;    Hydrocarbons;    02 Petroleum;    Reaction Kinetics;    Residual Fuels;   

DOI  :  10.2172/809221
RP-ID  :  NONE
RP-ID  :  FG26-99FT40617
RP-ID  :  809221

美国|英语

来源: UNT Digital Library

【 摘 要 】

Significant work has been done by the investigators on the cerium oxide-copper oxide based sorbent/catalysts for the combined removal of sulfur and nitrogen oxides from the flue gases of stationary sources. A relatively wide temperature window was established for the use of alumina-supported cerium oxide-copper oxide mixtures as regenerable sorbents for SO{sub 2} removal. Preliminary evaluation of these sorbents as catalysts for the selective reduction of NO{sub x} gave promising results with ammonia, but indicated low selectivity when methane was used as the reductant. Since the replacement of ammonia by another reductant is commercially very attractive, in this project, four research components will be undertaken. The investigation of the reaction mechanism, the first component, will help in the selection of promoters to improve the catalytic activity and selectivity of the sorbents in the SCR with methane. This will result in new catalyst formulations (second component). If this research is successful, the combined SO{sub 2}-NO{sub x} removal process based on alumina-supported copper oxide-ceria sorbent/catalysts will become very attractive for commercial applications. The objective of the third component of the project is to develop an alternative SCR process using another inexpensive fuel, residual fuel oil, instead of natural gas. This innovative proposal is based on very scant evidence concerning the good performance of coked catalysts in the selective reduction of NO and if proven to work the process will certainly be commercially viable. The fourth component of the project involves our industrial partner TDA Research, and the objective is to evaluate long-term stability and durability of the prepared sorbent/catalysts. In the first year of the project, the catalysts were investigated by the temperature-programmed reduction (TPR) technique. The results from TPR indicated that the interaction with support appears to promote reduction at lower temperatures. Copper oxide in excess of monolayer coverage reduces at temperatures close to the reduction temperature of the unsupported copper oxide. Increased dispersion increases the support effect. Low activity of ceria in NO reduction may be due to its resistance to reduction at low temperatures.