The Effect of Additives on Cu/HZSM-5 Catalyst for DME Synthesis

The addition of ZnO or ZrO₂ into CuO/HZSM-5 was investigated for DME synthesis from syngas by using the reactive frontal chromatography method, TPR and in situ TPR. These promoters enhanced the catalytic activity of Cu/HZSM-5 and promotion with ZnO and ZrO₂ produced a maximum activity, which could be explained by the improvement of the dispersion of Cu and the promotion of CuO reduction. The Cu⁺ species existing during the reaction have been detected, based on which a Cu⁰ Cu⁺¹ redox cycle model was put forward.