Lanthanum Hierarchical SAPO-34: Synthesis, Characterization, and Catalysis Evaluation in Methanol to Propylene Process

Document Type : Research Article

Authors

1 College of Alborze, University of Tehran, Tehran, I.R. IRAN

2 Department of Organic Chemistry, School of Chemistry, College of Science, University of Tehran, Tehran, I.R. IRAN

10.30492/ijcce.2019.35974

Abstract

Hierarchical SAPO-34 molecular sieve has been synthesized with n-propylamine as a mesoscale template and used to prepare La-Hierarchical SAPO-34 by impregnation by Lanthanum nitrate and has been used in Methanol-to-Propylene (MTP) conversion process. La-H-SAPO-34 demonstrated higher activity and selectivity for propylene (48.9%) compared to a conventional SAPO-34 catalyst (28.7%) in a fixed-bed reactor under atmospheric pressure at 450 oC and WHSV of 1.0 h-1. High selectivity and longer catalytic lifetime (7 hours) of methanol to propylene conversion have been attributed to the reduction in the acidic character of active sites and the increasing mesopore volume. The catalyst has been characterized by XRD, FE-SEM, BET, NH3-TPD, and TGA techniques and compared with SAPO-34.

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