摘要
以拟薄水铝石、磷酸和硅溶胶为原料,以二正丙胺为模板剂,采用包埋法合成了ZSM-5/SAPO-11双微孔结构复合分子筛,并通过XRD、SEM、TEM、FT-IR、BET、NH3-TPD等手段对复合分子筛进行了表征。结果表明,合成的复合分子筛是一种ZSM-5(核)/SAPO-11(壳)式双微孔复合分子筛。将该复合分子筛用于乙醇脱水制乙烯反应,虽然催化活性略低于ZSM-5分子筛,但稳定性比ZSM-5有大幅度提高。综合考虑催化活性和稳定性,ZSM-5/SAPO-11复合分子筛更适合作为乙醇脱水制乙烯的催化剂。
ZSM-5/SAPO-11 bimicroporous structure zeolite samples were synthesized with phosphoric acid,pseudoboehmite and silica sol as raw materials,and di-n-propylamine as template.The synthesized zeolite samples were characterized by means of X-ray powder diffraction,scanning electron microscopy（SEM）,transmission electron microscope（TEM）,Fourier transform infrared（FT-IR） spectroscopy,brunauer-emmett-teller（BET） and temperature-programmed adsorption of ammonia（TPD）,respectively.The ZSM-5/SAPO-11 sample had different structure compared with the mechanical mixture of ZSM-5 and SAPO-11,with ZSM-5 phase as the core and the SAPO-11 phase as the shell.Compared with the ZSM-5 catalyst,the ZSM-5/SAPO-11 composite had weaker acid sites.The catalytic performance of ZSM-5 and the composite catalysts for ethanol dehydration was carried out and the results indicated that higher ethanol conversion and ethylene selectivity were obtained over ZSM-5 catalyst.As to the stability of catalyst,the ZSM-5/SAPO-11 composite was better than ZSM-5.Considering the activity and stability of the ZSM-5 and the composite catalysts comprehensively,the ZSM-5/SAPO-11 composite was the suitable catalyst in ethanol dehydration.
出处
《石油学报（石油加工）》
EI
CAS
CSCD
北大核心
2012年第2期310-316,共7页
Acta Petrolei Sinica(Petroleum Processing Section)
