USE OF ALUMINUM PHOSPHATE AS THE DEHYDRATION CATALYST IN SINGLE STEP DIMETHYL ETHER PROCESS

摘要

The present invention pertains to a process for the coproduction of methanol and dimethyl ether (DME) directly from a synthesis gas in a single step thereaft er, the "single step DME process"). In this process, the synthesis gas comprising hydrog en and carbon oxides is contacted with a dual catalyst system comprising a physical mixture of a methanol synthesis catalyst and a methanol dehydration catalyst. Th e present invention is an improvement to this process for providing an active and stable catalyst system. The improvement comprises the use of an aluminum phosphate base d catalyst as the methanol dehydration catalyst. Due to its moderate acidity, such a catalyst avoids the coke formation and catalyst interaction problems associated with the conventional dual catalyst systems taught for the single step DME process.