改性Y分子筛的酸碱性能及吸附性能的研究; Studies on Acidity and Basicity and Adsorption of Modified Y Zeolites | |
周灵萍 ; 邓量 ; 寇元 ; 李宣文 | |
2002 | |
关键词 | 改性八面沸石 表面酸碱性 芳烃吸附 TPD FTIR modified Y zeolites TPD FTIR surface acidity and basicity aromatic hydrocarbon adsorption |
英文摘要 | 吡啶、吡咯、苯、甲苯、乙苯作为探针分子,在Li+,Na+,K+,Cs+改性的Y型分子筛上进行吸附,用TPD及IR方法系统地研究了不同碱金属离子改性的Y型分子筛的酸碱性能和吸附性能的变化.结果表明,按Li、Na、K、Cs的顺序,随着碱金属离子半径的增大,其L酸酸强度依次减弱,L碱的强度逐渐增强.由于改性Y型分子筛所含碱金属离子的不同,其对芳烃的吸附的强弱及吸附量的大小亦不同.随着骨架外的阳离子的半径逐渐增大,碱的强度逐渐增强,与芳烃的作用愈强烈,导致TPD脱附峰温增高及芳烃和侧链上的C-H伸缩振动谱带向低波数位移愈多.由于位阻的原因,对含同一种碱金属离子的分子筛来说,随着芳烃侧链C数的增加,芳烃的吸附量逐渐减小.; The acidity and basicity of alkali cation exchanged Y zeolites were investigated systematically using pyridine and pyrrole as the TPD and IR spectroscopic probe respectively. It was found that the overall Lewis basicity in the modified Y zeolites increased and the Lewis acidity in the modified Y zeolites decreased as the cation was exchanged from LiY to CsY in the alkali cation series. The adsorption of benzene, toluene and ethylbenzene on Y zeolites modified by alkali cations were also studied comparatively by IR spectroscopy and TPD. The following results were obtained: (1) The adsorption of pyridine on modified Y zeolites could also be used to characterize the acidity and basicity of alkali cation exchanged Y zeolites; (2) The C - H stretching frequencies of aromatic ring, of CH3 on the side-chain of toluene, and of - CH2 - on the side-chain of ethylbenzene shifted towards lower wavenumber as the cation was exchanged from LiY to CsY; (3) The adsorption strength and the amount of sorbed aromatics on modified Y zeolites were related to the basicity of alkali cation exchanged Y zeolites.; 国家自然科学基金; http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000173613600010&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701 ; SCI(E); 中文核心期刊要目总览(PKU); 中国科技核心期刊(ISTIC); 中国科学引文数据库(CSCD); 3; 2; 142-146; 18 |
语种 | 中文 |
出处 | 万方 ; SCI ; http://d.g.wanfangdata.com.cn/Periodical_wlhxxb200202010.aspx |
出版者 | 物理化学学报 |
内容类型 | 其他 |
源URL | [http://hdl.handle.net/20.500.11897/78382] ![]() |
专题 | 化学与分子工程学院 |
推荐引用方式 GB/T 7714 | 周灵萍,邓量,寇元,等. 改性Y分子筛的酸碱性能及吸附性能的研究, Studies on Acidity and Basicity and Adsorption of Modified Y Zeolites. 2002-01-01. |
个性服务 |
查看访问统计 |
相关权益政策 |
暂无数据 |
收藏/分享 |
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。
修改评论