表面活性剂对SAPO-34晶体形貌的调控研究

doi:10.13218/j.cnki.csdc.2018.07.004

Abstract

Abstract: The layered and small crystals of SAPO-34 molecular sieve were synthesized by adding a certain amount of octadecyltrimethylammonium bromide (STAB) and using pseudoboehmite as aluminum source,phosphoric acid as phosphorus source,silica sol as silicon source,and triethylamine and tetraethylammonium hydroxide as templates.The samples were characterized by XRD,SEM,FT-IR,NH₃-TPD and BET.The catalytic performances of these samples for converting methanol to olefins (MTO) were also evaluated.Results show that,due to the presence of STAB,a specific organic sequence is formed in the reaction and therefore the particle size becomes smaller and thinner and the content of strong acid increases slightly.In contrast with the molecular sieve samples prepared by traditional methods,it has higher catalytic lifetime and selectivity to ethylene and propylene.

Key words: octadecyltrimethylammonium bromide, SAPO-34 molecular sieve, layered, small crystal, conversion of methanol to olefins

CLC Number:

TQ423.12

HE Zu-guang,LI Xiao-feng,DI Chun-yu,LI Zhi-hong,GUO Yun-ya,DOU Tao. Study on the control of SAPO-34 crystal morphology by the surfactant[J].China Surfactant Detergent & Cosmetics, 2018, 48(7): 382-387.

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Study on the control of SAPO-34 crystal morphology by the surfactant

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