摘要
综述了二十年来烯烃烷烃新型分离吸附剂的研究进展,与传统的π络合吸附剂相比,优先吸附烯烃的吸附剂包括金属有机材料(MOF)、Engelhard Titanosilicate(ETS)、高硅分子筛和介孔分子筛,主要是利用氢键作用、孔径大小、分子扩散速率差异或π络合作用,将烷烃烯烃分离;而优先吸附烷烃的吸附剂包括AlMePO-α、ZIF-7和凹凸棒黏土,主要利用吸附剂上甲基与烷烃的相互作用。MOF对烯烃吸附量大,但选择性较差;高硅分子筛对烯烃的动力学分离效果良好;介孔分子筛经过渡金属改性后,对烯烃有优良的选择性;ETS类对烯烃有较高的吸附量和选择性,且稳定性强,有很好的应用前景。
This review focuses on the research progress on new type adsorbent for olefin/paraffin in separating alkene in twenty years. Compared with the tradition adsorption via pi-complexation, the adsorption mechanism of the adsorbent for preferential adsorption of olefin is pore size, difference in molecular diffusion, hydrogen bond interaction or pi complexation in separation of olefin/paraffin. This kind of adsorbent includes metallo-organic frameworks, Engelhard Titanosilicate （ETS）, mesoporous molecular sieve and high silica zeolite. The adsorbent for preferential adsorption of paraffin, such as aluminum methylphosphonate-α, zeolite imidazolate framework ZIF-7 and attapulgite, utilizes the interaction between methyl and paraffin. Olefin presents very high adsorption capacity in metallo-organic frameworks in contrast to other types of adsorbent, due to its high surface area, but the selectivity coefficient for olefin over paraffin is less than 2 at normal pressure. High silica zeolite exhibits satisfactory heat stability and acid stability, which is an excellent adsorbent in a kinetic based process for the separation of propene and propane. Mesoporous molecular sieves have little selectivity for olefin, so they do not meet the needs in industry. With some transition metal cations loaded, such as Cu＋ and Ag＋, the modified adsorbent possess favorable adsorption capacity and selectivity for olefin. The selectivity and adsorption capacity of ETS are satisfactory after several cycles of desorption, indicating that this adsorbent adapts to industrial applications.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2014年第2期396-405,共10页
CIESC Journal
基金
国家高技术研究发展计划项目(2012AA040305)~~
关键词
烷烃
烯烃
吸附剂
吸附
分离
paraffin
olefin
adsorbents
adsorption
separation
