In situ synthesized nano-copper over ZSM-5 for the catalytic dehydration of glycerol under mild conditions

Cu/ZSM-5 prepared by in situ impregnated reduction was used for the catalytic dehydration of glycerol under solvent-free conditions. The catalyst was characterized by X-ray diffraction (XRD, transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), ammonia temperature programmed desorption (NH3-TPD), and thermogravimetry-differential scanning calorimetry (TG-DSC) analyses. Results showed that the nano-copper in Cu/ZSM-5 was evenly distributed onto the surface of ZSM-5 pores. Under the optimum conditions of the catalytic dehydration of glycerol, conversion was 92.1 wt.%. The selectivities of acrolein and acetol were 80.4 wt.% and 11.5 wt.%, respectively. Moreover, the low temperature favored for acetol selectivity. The synergic catalysis of Cu and ZSM-5 through the enol intermediate was responsible for the selectivity in the catalytic dehydration of glycerol.