Patent ID: 7435759

Claim:
A method for producing dimethylether (DME), which comprises the steps of: (i) introducing a feed gas mixture containing hydrogen and CO to a DME synthesis reactor, wherein the feed gas mixture is reacted in the presence of a methanol synthesis catalyst and an acid catalyst for the dehydration of methanol, to provide a crude product stream containing DME and CO 2 ; (ii) separating the crude product stream into a CO 2 rich stream and a DME rich stream; (iii) introducing the CO 2 rich stream to a reverse water gas shift (RWGS) reactor wherein it is reacted with hydrogen separately introduced in the presence of an oxide catalyst to provide a CO rich stream, while recovering the DME rich stream as a product, the oxide catalyst being ZnO supported on or coprecipitated with an oxide selected from Al 2 O 3 , ZrO 2 , MgO, SiO 2 and a mixture thereof and the reaction in the reverse water gas reactor being carried out at a temperature ranging from 500 to 900° C.; and (iv) recycling the CO rich stream to step (i).