Advance concepts for the conversion of syngas to liquids. Quarterly report No. 8, October 1, 1996--December 31, 1996

摘要

Large pore Metal Substituted Aluminophosphate Molecular sieves, (H-MAPO-5, H-MnAPO-5, H-CoAPO-5 and H-MAPO-36) were evaluated for the conversion of ethanol in a continuous flow fixed microreactor. At 400(degrees)C, high conversion levels were observed. Ethylene and diethyl ether were the two major products obtained however the catalysts were more selective for ethylene under the reaction conditions. At 500(degrees)C ethylene was the only product detected. The low concentration of acid sites combined with the possibly mild acid strengths of the molecular sieves were speculated to be possible reasons for the absence of higher hydrocarbons form the reaction products. Trends for the catalytic behavior of the various catalysts were unpredictable due to a number of reasons. Among these are (1) differing levels of divalent metal substitution, (2) varying amount of extraframework species which can have tremendous negative impact on catalytic performance, (3) differing levels of H(sup +) exchange, and (4) differing levels of crystallinity and thermal stability.