催化学报 ›› 2008, Vol. 29 ›› Issue (9): 889-894.

• 研究论文 • 上一篇    下一篇

磷改性MCM-22分子筛上苯与1-十二烯烷基化合成十二烷基苯

田玲,李建伟,李英霞,陈标华   

  1. 北京化工大学化工资源有效利用国家重点实验室, 北京 100029
  • 收稿日期:2008-09-25 出版日期:2008-09-25 发布日期:2012-07-19

Synthesis of Dodecylbenzene with Benzene and 1-Dodecene over MCM-22 Zeolite Modified with Phosphorus

TIAN Ling, LI Jianwei*, LI Yingxia, CHEN Biaohua   

  1. State Key Laboratory of Chemical Resources Engineering, Beijing University of Chemical Technology, Beijing 100029, China
  • Received:2008-09-25 Online:2008-09-25 Published:2012-07-19

摘要: 采用浸渍法制备了一系列用于苯和1-十二烯烷基化合成十二烷基苯的磷改性MCM-22分子筛,以X射线衍射(XRD)和固体27Al、31P核磁共振, N2吸附,氨程序升温脱附(NH3-TPD), 热重(TG)和红外光谱(FT-IR)等表征技术,结合固定床连续流动反应器中的性能评价,较为系统地研究了磷改性对MCM-22分子筛的结构、表面酸性及其烷基化催化性能的影响. 结果表明,用磷改性MCM-22分子筛虽然不会影响分子筛的晶体结构,但是会破坏分子筛上的Si-O-Al键,使部分四配位铝转化为六配位铝. 由于聚合态的磷酸盐可能与Al发生键合,多聚态磷酸盐数量随着磷含量的增加而增多,从而改变了分子筛的孔道大小和酸性,使得强酸减少,弱酸增多,酸强度降低,总酸量和B酸中心数随着磷含量的增加呈现先增后减的规律, L酸减少. 适当的磷含量有利于提高MCM-22分子筛对苯与1-十二烯烷基化反应的催化选择性和稳定性,改性磷含量为0.5%左右时产物2-十二烷基苯收率最高.

关键词: MCM-22分子筛, 磷改性, 苯, 1-十二烯, 烷基化

Abstract: With increasing phosphorus content, the MCM-22 zeolite acidity was reduced and the quantity of weak acid sites increased gradually, whereas the strong acid sit es decreased. A proper phosphorus content can improve the selectivity for 2-dod ecylbenzene and the catalytic stability of the MCM-22 catalyst. The maximum yie ld of 2-phenyldodecane was obtained with a phosphorus content of 0.5%.

Key words: MCM-22 zeolite, phosphorus modification, benzene, 1-dodecene, alkylation