ISOMERIZATION OF N-HEPTANE ON AN OXYGEN-MODIFIED MOLYBDENUM CARBIDE CATALYST

被引：126

作者：

BLEKKAN, EA ^{[1
]}

CUONG, PH ^{[1
]}

LEDOUX, MJ ^{[1
]}

GUILLE, J ^{[1
]}

机构：

[1] UNIV LOUIS PASTEUR,EHICS,CHIM MAT CATALYT LAB,1 RUE BLAISE PASCAL,F-67000 STRASBOURG,FRANCE

来源：

INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH | 1994年 / 33卷 / 07期

关键词：

D O I：

10.1021/ie00031a003

中图分类号：

TQ [化学工业];

学科分类号：

0817 ;

摘要：

The isomerization of n-heptane in the presence of hydrogen has been carried out over a molybdenum carbide catalyst modified by an oxygen treatment. Heptane was isomerized selectively to isoheptanes, a reaction which is difficult over traditional bifunctional catalysts due to extensive cracking. The C7 products were mainly monomethylhexanes, 2-methylhexane and 3-methylhexane, in close to equilibrium ratios. A typical bifunctional catalyst (Pt supported on an acidic zeolite) gave similar isomerization products, but mostly propane and isobutane as the cracked products. The selectivity over the oxidized carbide was found to be a function of pressure but independent of the conversion; increased the hydrogen pressure led to a decrease in the C7 selectivity. This was found to be different from the Pt/zeolite catalyst, over which the selectivity was a function of the conversion; a high selectivity was only obtained at low conversions. The active carbide-based catalyst was probably an oxycarbide of molybdenum. The results obtained over the oxidized carbide catalyst are discussed in terms of a bond-shift mechanism via a metallocyclobutane intermediate.

引用

页码：1657 / 1664

页数：8

共 31 条

[11] COMPARED ACTIVITIES OF PLATINUM AND HIGH SPECIFIC SURFACE-AREA MO2C AND WC CATALYSTS FOR REFORMING REACTIONS .1. CATALYST ACTIVATION AND STABILIZATION - REACTION OF NORMAL-HEXANE [J].