改性分子筛催化C4+混合烃制低碳烯烃的性能研究OA北大核心CSTPCD

In the process of methanol to olefins,a large number of C4+ mixed hydrocarbons are generated as by-product.Using C4+ mixed hydrocarbons to efficiently produce and improve the yield of ethylene and propylene has become an important research direction in the coal-to-olefin industry.Nano-sized HZSM-5 molecular sieve was synthesized by hydrothermal method.P modified HZSM-5 molecular sieve catalyst(P/HZSM-5)and P-Mg composite modified HZSM-5 molecular sieve catalyst(P-Mg/HZSM-5)were prepared based on nano-sized HZSM-5 molecular sieve respectively.The prepared molecular sieve and corresponding catalysts were characterized by XRD,SEM and N2 absorption/desorption.The experiment of C4+ mixed hydrocarbons to produce light olefins catalyzed by nano-sized HZSM-5 molecular sieve and molecular sieve catalysts respectively,was carried out in a small fixd-bed reactor.The results show that the yield of ethylene and propylene of P-Mg/HZSM-5 can reach 46.2%with the best overall performance(the coversion rate of ethylene is 28.6%and the coversion rate of propylene is 60.8%)at the condition of temperature of 520℃,pressure of 0.2 MPa,steam space velocity of 1000 h-1 and raw mixed gas volume space velocity of 100 h-1 for 8 h.