【摘要】：采用水蒸氣輔助晶化法合成ZSM-5、ZSM-11和多級孔ZSM-11分子篩,運用XRD、SEM、NH3-TPD、N2吸附-脫附和TG方法對合成的分子篩進行表征。結(jié)果表明:所合成的ZSM-5和ZSM-11分子篩的比表面積、微孔體積、晶粒大小和酸性等物化性質(zhì)相似;多級孔ZSM-11分子篩引入了大量介孔,微孔體積得以保留。合成的分子篩催化苯與甲醇烷基化反應(yīng)結(jié)果表明,ZSM-11相對于ZSM-5表現(xiàn)出更高的反應(yīng)活性和穩(wěn)定性,這是因為C7、C8等芳烴分子在ZSM-11孔道內(nèi)擴散更快;多級孔ZSM-11相對于微孔ZSM-11反應(yīng)活性進一步提升,在反應(yīng)溫度460℃、壓力0.2 MPa、質(zhì)量空速3 h-1的條件下,苯轉(zhuǎn)化率達(dá)到54.3%,甲苯和二甲苯總選擇性達(dá)到91.9%,其中二甲苯選擇性為37.9%,該催化劑在反應(yīng)240 h內(nèi)保持良好的穩(wěn)定性,相對于微孔ZSM-11,壽命顯著提升。
[Abstract]:ZSM-5,ZSM-11 and multiporous ZSM-11 molecular sieves were synthesized by steam assisted crystallization. The synthesized molecular sieves were characterized by XRD,SEM,NH3-TPD,N2 adsorption-desorption and TG. The results show that the specific surface area, micropore volume, grain size and acidity of the synthesized ZSM-5 and ZSM-11 molecular sieves are similar, and a large number of mesoporous ZSM-11 molecular sieves are introduced, and the micropore volume can be retained. The alkylation of benzene with methanol catalyzed by the synthesized molecular sieves showed that ZSM-11 showed higher activity and stability than ZSM-5, which was due to the faster diffusion of aromatic molecules such as C8 and C8 in the ZSM-11 channel. The reaction activity of multistage pore ZSM-11 was further improved compared with that of microporous ZSM-11-11. under the conditions of reaction temperature 460 鈩，

本文編號：2495271