Heteropolyacid catalysts for hydroisomerization of n-hexane:: Effects of alkali salt modification

被引：33

作者：

Essayem, N ^{[1
]}

Ben Taârit, Y ^{[1
]}

Gayraud, PY ^{[1
]}

Sapaly, G ^{[1
]}

Naccache, C ^{[1
]}

机构：

[1] CNRS, Inst Rech Catalyse, Convent UCB Lyon, F-69622 Villeurbanne, France

来源：

JOURNAL OF CATALYSIS | 2001年 / 204卷 / 01期

关键词：

hydroisomerization; acidity; heteropolyacids; alkanes; n-hexane;

D O I：

10.1006/jcat.2001.3341

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

12-Tungstophosphoric acid, H3PW12O40, and a series of its acid alkali salts associated with silica-supported platinum have been used as catalysts in the hydroisomerization of n-hexane and compared with platinum-supported, appropriately dealuminated mordenite. High selectivity toward isomerization was observed with both the heteropolyacid (HPA)-type catalysts and the mordenite at elevated conversions. The acid sites of the heteropolyacids/salts exhibited an efficiency higher than that of mordenite, in line with the higher acid strength of the former sites. Yet, despite their higher acid strength, heteropolyacids/salts showed a lower selectivity toward dimethylbutanes than mordenite. In addition, heteropolyacids, though more active than mordenite at low temperature, appeared to be only poor monofunctional isomerization catalysts. (C) 2001 Academic Press.

引用

页码：157 / 162

页数：6

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