关键词: SAPO-34, 表面酸性, 酸强度, 失活, 晶粒尺寸, 金属改性

Abstract: SAPO-34 molecular sieve with moderate acidity and characteristic small pore structure exhibits super selectivity to C2-C3 olefins during the conversion of methanol to light olefins (MTO). However, the catalytic performance of SAPO-34 molecular sieve catalyst mainly depends on its physicochemical characteristics, such as pore structure, surface acidity, crystal size and chemical compositions. Thus, a fully understanding of the relationship between physicochemical property and catalytic performance of the catalyst is helpful for an optimum catalyst design. In this paper the effects of physicochemical properties of SAPO-34 on the catalytic performance including activity, selectivity, thermal and hydrothermal stability of the catalyst in MTO process are analyzed, as well as various methods for adjusting the acidity, crystal size, pore structure and chemical compositions of SAPO-34 are summarized.

Key words: SAPO-34, surface acidity, acid strength, deactivation, crystal size, metal modification