铵盐改性对β分子筛的酸性及其催化二异丙苯异构化反应性能的影响  

Effects of Ammonium Salts Modification on Acidity of β Molecular Sieve and Its Catalytic Performances in Diisopropylbenzene Isomerization

作　　者：赵培侠[1] 刘靖[1] 张春勇[1] 

机构地区：[1]大连理工大学精细化工国家重点实验室催化化学与工程系,辽宁大连116012

出　　处：《石油化工》2005年第6期527-531,共5页Petrochemical Technology

摘　　要：考察了三元有机酸铵盐(柠檬酸三铵和柠檬酸氢二铵)和传统的硝酸铵对β分子筛改性的影响,采用X射线粉末衍射、氨吸附-程序升温脱附和吡啶吸附红外光谱技术对催化剂进行表征,并将改性后的催化剂用于二异丙苯的异构化反应。实验结果表明,用柠檬酸三铵对β分子筛进行改性时,由于柠檬酸根与分子筛中的非骨架铝络合,使β分子筛在脱铝的同时保持较高的结晶度,同时增加β分子筛中的强B酸量;在催化二异丙苯异构化反应中,柠檬酸三铵改性的β分子筛催化剂有较高的催化活性和选择性,温度对其影响不大,稳定性较好。Hβ-1, Hβ-2 and Hβ-3 molecular sieves modified with NH4NO3, diammonium citrate and triammonium citrate respectively were characterized by means of XRD, NH3-TPD and IR, and used as catalysts for diisopropylbenzene (DIPB) isomerization. Effects of ammonium salts modification on acidity of β molecular sieve and on its catalytic performances for diisopropylbenzene isomerization were studied. Hβ-3 molecular sieve retained high relative crystallinity when it was dealuminized and contained higher amount of strong Bronsted acid sites than Hβ-1 molecular sieve. Hβ-3 molecular sieve catalyst exhibited high catalytic activity, 1,3-DIPB selectivity and stability in DIPB isomerization.

关 键 词：Β分子筛 异构化 柠檬酸氢二铵 柠檬酸三铵 二异丙苯 间二异丙苯 催化剂 

分 类 号：TQ424.25[化学工程]