高硅MFI分子筛孔道调控及其乙烷/乙烯吸附分离性能研究  

Study on pore regulation of high-silica MFI zeolites and their ethane/ethylene adsorption separation performances

作　　者：熊峰 柯权力 卢梅 方国楠 潘鹏云 牛晓坡 崔国凯 卢晗锋[1] XIONG Feng;KE Quanli;LU Mei;FANG Guonan;PAN Pengyun;NIU Xiaopo;CUI Guokai;LU Hanfeng(Institute of Catalytic Reaction Engineering,College of Chemical Engineering,Zhejiang University of Technology,Hangzhou 310014,Zhejiang,China;Zhejiang Environmental Technology Co.,Ltd.,Hangzhou 311121,Zhejiang,China)

机构地区：[1]浙江工业大学化学工程学院催化反应工程研究所,浙江杭州310014 [2]浙江环境科技有限公司,浙江杭州311121

出　　处：《低碳化学与化工》2024年第11期97-103,共7页Low-Carbon Chemistry and Chemical Engineering

基　　金：国家自然科学基金(22208300);浙江省自然科学基金(LQ23B060007);浙江省教育厅科研基金(Y202352744);浙江省“尖兵”“领雁”研发攻关计划(2023C03127,2024C03114,2024C03108);浙江省属高校基本科研业务费专项资金(RF-A2023004);浙江省博士后科研择优资助项目(ZJ2023145)。

摘　　要：借助固体吸附分离技术可获得高纯度乙烯,对提高乙烯产品质量有重要意义。采用表面修饰策略对Mn掺杂高硅MFI分子筛(H-MFI-Mn)进行修饰分别制得P修饰H-MFI-Mn(H-MFI-Mn-P)和HCOOH修饰H-MFI-Mn(H-MFI-Mn-COOH和H-MFI-Mn-P-COOH)。采用XRD、SEM和N_(2)吸/脱附等对所得分子筛进行了表征。在混合气体中(V(乙烯):V(乙烷)=50:50)对所得分子筛的乙烷/乙烯吸附分离性能进行了评价,并采用UV-Vis和XPS对所得分子筛的乙烷/乙烯吸附分离机理进行了分析。结果表明,H-MFI-Mn-P-COOH的微孔孔径(0.68 nm)和平均孔径(2.70 nm)较H-MFI-Mn的孔径(0.55 nm)和平均孔径(1.61 nm)明显增大。与H-MFI-Mn的比表面积(446 m^(2)/g)相比,H-MFI-Mn-P、H-MFI-Mn-COOH和H-MFI-Mn-P-COOH的比表面积(400 m^(2)/g左右)均有所减小。H-MFI-Mn-P-COOH表现出较好的乙烷/乙烯吸附分离性能,其乙烷动态平衡吸附容量为1 mmol/g,乙烷/乙烯动态分离选择性为2.08。与H-MFI-Mn相比,H-MFI-Mn-P-COOH中Mn^(3+)和Mn^(2+)在总Mn离子中的占比较高,说明P修饰+HCOOH修饰可削弱分子筛结构中Mnδ+物种的电子转移性能,进而抑制H-MFI-Mn-P-COOH的乙烯吸附性能。High purity ethylene can be obtained by the solid adsorption separation technology,which is of great significance to improve the quality of ethylene products.Mn-doped high-silica MFI zeolite(H-MFI-Mn)were modified by surface modification strategy to obtain P-modified H-MFI-Mn(H-MFI-Mn-P)and HCOOH-modified H-MFI-Mn(H-MFI-Mn-COOH and H-MFI-Mn-P-COOH),respectively.The prepared zeolites were characterized by XRD,SEM and N_(2) adsorption/desorption,etc.The ethane/ethylene adsorption separation performances of prepared zeolites were evaluated in mixed gas(V(ethane):V(ethylene)=50:50).And the ethane/ethylene adsorption separation mechanisms of prepared zeolites were analyzed by UV-Vis and XPS.The results show that the micropore size(0.68 nm)and average pore size(2.70 nm)of H-MFI-Mn-P-COOH are significantly larger than the micropore size(0.55 nm)and average pore size(1.61 nm)of H-MFI-Mn.Compared with the specific surface area of H-MFI-Mn(446 m^(2)/g),the specific surface areas(about 400 m^(2)/g)of H-MFI-Mn-P,H-MFI-Mn-COOH and H-MFI-Mn-P-COOH decrease.H-MFI-Mn-P-COOH shows better ethane/ethylene adsorption separation performance with ethane dynamic equilibrium adsorption capacity of 1 mmol/g and ethane/ethylene dynamic separation selectivity of 2.08.Compared with H-MFI-Mn,Mn3+and Mn2+in H-MFI-Mn-P-COOH accounted for higher proportions in total Mn ions,indicating that P-modification+HCOOH-modification can weaken the electron transfer performance of Mnδ+species in the zeolite structure,and then inhibit the ethylene adsorption performance of H-MFI-Mn-P-COOH.

关 键 词：高硅MFI分子筛 乙烷/乙烯吸附分离 表面修饰 

分 类 号：TQ424.23[化学工程]