改性HZSM-5催化合成异丙醇胺  

Synthesis of isopropanolamine catalyzed by modified HZSM-5

作　　者：王泽尧 姚风浩 彭程 冯忠祥 于如军 郭文杰 WANG Ze-yao;YAO Feng-hao;PENG Cheng;FENG Zhong-xiang;YU Ru-jun;GUO Wen-jie(School of Chemistry and Chemical Engineering,Shandong University of Technology,Zibo 255000,Shandong Province,China;Shandong Damin Chemical Co.,Ltd.,Binzhou 256800,Shandong Province,China)

机构地区：[1]山东理工大学化学化工学院,山东淄博255000 [2]山东达民化工股份有限公司,山东滨州256800

出　　处：《化学工程》2022年第11期50-54,共5页Chemical Engineering(China)

基　　金：山东省自然科学基金资助项目(ZR2020MB121)。

摘　　要：利用等体积浸渍法和离子交换法对硅铝摩尔比38的HZSM-5进行硝酸钾、硝酸钠和磷酸氢二铵离子改性,并采用XRD、BET、NH_(3)-TPD等表征方法对催化剂结构和酸性进行表征。在自制微型固定床反应器上对离子改性前后的HZSM-5分子筛上进行环氧丙烷的开环氨解反应活性评价,考察离子改性对催化剂晶体结构、酸性、孔结构以及催化剂性能的影响。结果表明:离子改性不会破坏分子筛的晶体结构,改性前后均具有较高的比表面积、孔容积、孔径,不同离子改性对分子筛的酸性影响较大,强酸密度均有所降低,有效提高了一异丙醇胺的选择性,延长催化剂使用寿命。相比未处理的HZSM-5分子筛,K+离子改性后的分子筛强酸性位点完全消失,相同反应条件下一异丙醇胺选择性由42.29%提升至73.72%,连续运转120 h转化率仍保持在90%以上,表现出良好的催化性能。HZSM-5 with Si/Al molar ratio of 38 was modified by KNO_(3),NaNO_(3)and(NH_(4))_(2)HPO_(4)through impregnation and ion exchange.The structure and acidity of the catalyst were characterized by XRD,BET and NH_(3)-TPD.The catalytic activity of HZSM-5 zeolite before and after ion modification for the ring-opening ammonolysis of propylene oxide was evaluated in a self-made micro-fixed-bed reactor,and the effects of ion modification on the crystal structure,acidity,pore structure and catalytic performance of the catalyst were investigated.The results show that the ionic modification can not destroy the crystal structure of the zeolite,and the zeolite has higher specific surface area,pore volume and pore size before and after modification.The ionic modification has a great influence on the acidity of the zeolite,and the density of strong acid decreases,which effectively improves the selectivity of monoisopropanolamine and prolongs the service life of the catalyst.Compared with the untreated HZSM-5 zeolite,the strong acid sites of the K^(+)-modified HZSM-5 zeolite completely disappear,and the selectivity of monoisopropanolamine increases from 42.29%to 73.72%under the same reaction conditions,and the conversion of monoisopropanolamine remaines above 90%after 120 h continuous operation,showing good catalytic performance.

关 键 词：HZSM-5分子筛 环氧丙烷 异丙醇胺 离子交换 等体积浸渍 固定床 

分 类 号：TQ028.8[化学工程]