Relative Roles of Methanol Synthesis and Solid Acid Catalysts in the Direct DME Synthesis from Syngas

The Cu/ ZnO / Al 2 O 3 catalysts with 13.0 and 30.6 m 2 Cu/g were designated as HM (highly active catalysts for methanol synthesis) and LM (low active catalysts for methanol synthesis), respectively. γ‐ Al 2 O 3 and η‐ Al 2 O 3 were designated as LD (low active catalysts for methanol dehydration) and HD (highly active catalysts for methanol dehydration), respectively. Four catalytic systems ( LMLD , LMHD , HMLD, and HMHD ) were prepared by admixing methanol synthesis catalysts and methanol dehydration catalysts. The syngas to dimethyl ether ( DME) ( STD ) reaction was conducted at a GHSV of 6000 mL/g cat /h, 42 atm, and 250 °C. The activity of LMLD was almost same as that of LMDH , indicating that the activity of solid acid catalysts did not influence the STD reaction on the admixed catalysts using LM . On the other hand, the activity of HMHD was much higher than that of HMLD , indicating that the solid acid catalysts controlled the STD reaction on the admixed catalysts using HM .