Methanol to propylene: Effect of phosphorus on a high silica HZSM-5 catalyst

Modified high silica HZSM-5 catalysts have been used to selectively transform methanol to propylene (MTP). The HZSM-5 catalyst with a Si/Al ratio of 220 exhibited satisfying catalytic performance (space time yield of propylene is up to 18 mmol/gh). The selectivity of propylene can be obviously affected by additives. P leads to a pronounced improvement of propylene selectivity up to 55.6% with complete conversion of methanol. The enhancement of propylene selectivity and catalytic life can be attributed to partial elimination of the strong acid sites on the HZSM-5 catalyst. (C) 2009 Elsevier B. V. All rights reserved.