投料顺序对酸性H-ZSM-5的直接合成及MTP性能的影响

Effect of Feeding Sequence on Direct Synthesis of Acid H-ZSM-5 and MTP Performance

采用硅源＋碱＋铝源、铝源＋碱＋硅源、铝源＋硅源＋碱三种投料顺序合成酸性H-ZSM-5,系统考察了其对H-ZSM-5晶化过程及物理化学性质的影响。以XRD、SEM、NH3-TPD、Py-FTIR等技术对合成的样品进行了表征,以甲醇制丙烯（MTP）反应测试了其催化性能。结果表明,以硅源＋碱＋铝源顺序合成的H-ZSM-5的晶粒粒度较小,MTP反应性能最佳,其中丙烯选择性30.66%,乙烯选择性32.01%,C2=~C4=总选择性为72.56%,较商业购买的ZSM-5高30%。

H-ZSM-5 zeolites were successfully synthesized with three feeding sequence as silicon source ＋ alkali＋ aluminum source,aluminum source ＋ alkali＋ silicon source,aluminum source ＋silicon source ＋ alkali,and the effect of feeding sequence on the synthesis and properties of H -ZSM-5 zeolites was studied in detail.The obtained samples were characterized by XRD,SEM, NH3-TPD,Py-FTIR methods,and their catalytic properties were evaluated through methanol to propylene （MTP）reaction.The results showed that,with the silicon source＋alkali＋aluminum source sequence synthesis of H-ZSM-5 particle size is the smallest,and the MTP reaction performance is the best,the propylene selectivity was 30.66%,the ethylene selectivity was 32.01%,C 2=~C4= total selectivity was 72.56%,ZSM-5 olefin selectivity was 30%higher than commercial purchase.