Selective synthesis of dimethylamine over rare earth modified mordenites

摘要

The selective synthesis of dimethlamine from ammonia and methanol over the rare earth modified mordenites in a fixed bed reactor was studied. A mordenite, NaM, was modified by different rare earth elements, such as Ce, Gd and Y, with cation-exchange method. The experimental results show that various modified mordenites have better catalytic properties compared to the unmodified mordenites. The Ce~4+ modified mordenite, prepared by treating with a solution of 0.1 mol/L Ce~4+ and calcining at 600 deg. C for 2～3 h after moulded with a binder (bentonite), exhibits both high conversion of methanol and selectivity to DMA, up to 99.8/100 and 50.3/100, respectively, at 400 dge. C and under ambient pressure, and has an improved stability against coking.