A durable and highly selective PbO/HZSM-5 catalyst for methanol to propylene (MTP) conversion

A series of MOx/HZSM-5 catalysts (MOx: PbO, Sb2O3 and Bi2O3) for the catalytic conversion of methanol to propylene were prepared by a wet impregnation method using M(NO3)(x) (M: Pb, Sb and Bi). The catalytic reactions were carried out at 470 degrees C, a weight hourly space velocity (WHSV) of 4 h(-1), p = 0.1 MPa, and a MeOH/H2O molar ratio of 1 in a fixed-bed reactor. The results indicated that the propylene/ethylene (P/E) ratio increased when Pb, Bi, and Sb were introduced into HZSM-5, which resulted in a reduction of the apparent pore size, the number and strength of the strong acid sites in the HZSM-5. Under the optimized conditions, the 2% PbO/HZSM-5 catalyst exhibited excellent catalytic performance with a propylene selectivity of 46.05%, an average P/E ratio of 8.80 and a catalyst life of more than 445 h. (C) 2017 Elsevier Inc. All rights reserved.