超强碱K_2O对甲苯甲醇侧链烷基化反应的影响（英文）  

Effect of K_2O on Side Chain Alkylation of Toluene with Methanol

作　　者：惠海涛[1,2] 高俊华[1] 张侃[1] 刘平[1] 

机构地区：[1]中国科学院山西煤炭化学研究所煤转化国家重点实验室,山西太原030001 [2]中国科学院大学,北京100049

出　　处：《分子催化》2014年第1期19-28,共10页Journal of Molecular Catalysis(China)

摘　　要：采用离子交换法、浸渍法和焙烧分解法制备了x%K2O/KLSX(x=0,1,2,3,4)催化剂,KLSX上的超强碱性位K2O通过KNO3分解制得.考察了x%K2O/KLSX的甲苯甲醇侧链烷基化反应催化性能及超强碱性位K2O对反应的影响.超强碱性位K2O可以更好的极化甲苯甲基,以及催化甲醇转化为烷基化中间体,甚至完全分解为CO和H2.KLSX和1%K2O/KLSX因碱性较弱所以活性较低,3%K2O/KLSX和4%K2O/KLSX因含超强碱性位太多和可利用L酸性位太少,其活性也很低.相比之下,2%K2O/KLSX具有足够量的弱L酸位来吸附甲苯,以及适当强度的碱性位来转化甲醇和活化甲苯甲基,因此具有较高的催化甲苯甲醇侧链烷基化反应活性.The catalysts of x% K2O/KLSX（x = 0, 1, 2, 3, 4） were prepared by ion exchanging and impregnating method from Low-silica zeolite X （LSX） , and superbase of K2O can be generated from de- composed KNO3 over KLSX. The effect of superbase on the catalytic performances of x% K2O/KLSX for side chain alkylation of toluene with methanol was investigated. The superbase sites of K2O can polarize the methyl group of toluene better, as well as convert methanol to alkylation intermediate, and even to carbon monoxide and hydrogen. KLSX and 1% K2O/KLSX exhibited low catalytic activity because of lo- wer alkalinity, 3% K2O/KLSX and 4% K2O/KLSX also exhibited low catalytic activity because their ex- cess amount of superbase sites and insufficient amount of weak Lewis acid sites. In contrast, 2% K2O/ KLSX showed high activity due to its adequate Lewis acid sites to adsorb toluene, as well as moderate al- kalinity to convert methanol to alkylating agent and activate toluene.

关 键 词：烷基化 甲苯 甲醇 KLSX K2O 

分 类 号：O643.32[理学—物理化学]