碱处理改性ZSM-5吸附分离间/对甲酚异构体

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中图分类号：TQ028.9 文献标志码：A DOI:10.3969/j.issn.1003-9015.2025.03.003

文章编号：1003-9015(2025)03-0401-09

Adsorption separation of p/m -cresol on alkali-treated ZSM-5

CHEN Guangmin， SUN Yongjie， CHEN Pengfei，LIU Dinghua，LIU Xiaoqin (College of Chemical Engineering，Nanjing Tech University，Nanjing 2118OO，China）

Abstract:For the adsorption separation of m/p -cresol isomers，NaZSM-5 molecular sievewith a Si/Al ratio of 50 was selected as precursor due to itssuperior separation factor.Accompanied byalkali-treatment in various concentration NaOH solutions，a series of modified ZSM-5 with hierarchical pores were successfully synthesized.The adsorbents were characterized by N2 adsorption-desorption and X-ray diffraction(XRD). Static and dynamic adsorption experiments were employed to investigate the adsorption separation performance of such modified ZSM-5 adsorbents，followed by kinetic principles analysis.From theresults，compared with the bare molecular sieves，the adsorption rate of P -cresol on modified ZSM-5 especially that treated by 0.2mol⋅L-1 NaOH solution at 85 C for ， so-called O.2-85-1 sample，was greatly enhanced. This improvement could be attributed to the enhanced mass transfer caused by introduced mesopores in O.2-85-1.In detail,on0.2-85-1,the adsorption equlibriumtime forp-cresol was shortened by 5O%，and its maximum adsorption capacity increased by 50 % ，from 3 03kg⋅m-3⋅d-1 to 454 kg⋅m-3⋅d-1 .Inaddition，according to the kinetic fitting results，the adsorption behaviors of P -cresol and m -cresol on the O.2-85-1 were in accordance with pseudo-second-order kinetic model，confirming an order of magnitude increase in adsorption rate after alkali treatment.

Key words: ZSM-5 molecular sieves； alkali treatment; cresol isomers；adsorption； kinetics

1前言

目前,煤焦油提取[1-3]和人工合成[45]是生产甲酚的主要方法,生成的甲酚是邻、间、对甲酚三者的混合物,其中间甲酚是一种重要的精细化工品,可作为合成香料和化妆品的原料[6，因此需要分离得到高纯度的间甲酚。（剩余17928字）