Highly reduced MoO sub 3 /Al sub 2 O sub 3 catalysts II. Hydrogenolyses of cyclopropane, methylcyclopropane, and propane

The preparation of Mo(0)/Al{sub 2}O{sub 3} by Mo(CO){sub 6}/DA;H{sub 3},300-500{degree};H{sub 2},650-950{degree} (Mo(CO){sub 6} deposited on highly dehydroxylated alumina, heated in flowing He to 300-500{degree}C and then in H{sub 2} to 650-950{degree}C) and by MoO{sub 3}/Al{sub 2}O{sub 3};H{sub 2},...

Full description

Saved in:
Bibliographic Details
Published in:Journal of catalysis 1989-04, Vol.116:2
Main Authors: Chung, Jong-Shik, Burwell, R.L. Jr
Format: Article
Language:English
Subjects:
02 PETROLEUM
020400 - Petroleum- Processing
ALKANES
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
BUTANE
CARBONACEOUS MATERIALS
CATALYST SUPPORTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL PREPARATION
CHEMICAL REACTIONS
CYCLOALKANES
DEHYDROGENATION
DEPOSITION
ELEMENTS
ETHANE
HYDROCARBONS
MATERIALS
METALS
METHANE
MOLYBDENUM
MOLYBDENUM COMPOUNDS
MOLYBDENUM OXIDES
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PROPANE
REDUCTION
REFRACTORY METAL COMPOUNDS
SYNTHESIS
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The preparation of Mo(0)/Al{sub 2}O{sub 3} by Mo(CO){sub 6}/DA;H{sub 3},300-500{degree};H{sub 2},650-950{degree} (Mo(CO){sub 6} deposited on highly dehydroxylated alumina, heated in flowing He to 300-500{degree}C and then in H{sub 2} to 650-950{degree}C) and by MoO{sub 3}/Al{sub 2}O{sub 3};H{sub 2},950{degree} give essentially equivalent results with respect to activity and selectivity in the hydrogenolyses of cyclopropane (CP) and methaylcyclopropane (MCP) at 100{degree}C and of propane at 250{degree}C. Thus, one can prepared metallic Mo on alumina by the easier and more flexible preparation from MoO{sub 3}/Al{sub 2}O{sub 3}. MCP undergoes single hydrogenolysis to isobutane and butane and double hydrogenolysis to (a) CH{sub 4} + C{sub 3}H{sub 8} and to (b) 2C{sub 2}H{sub 6}. The product ratio, butane/isobutane, is greater than unity which is uncommon on metals. After on to several pulses in a pulse reactor, catalyst samples were heated to 950{degree}C in flowing H{sub 2}. The amount of liberated methane gave the amount of carbonaceous deposit. With one to seven pulses of CP or MCP in H{sub 2}, (C atoms in deposit)/(C atoms in product) was 0.03-0.04 but only 0.007 with propane. Activities usually declined with pulse number, but selectivities changed little. The Mo(0)/Al{sub 2}O{sub 3} catalyst is initially metallic molybdenum and metallic molybdenum is catalytically active.
ISSN:0021-9517
1090-2694
DOI:10.1016/0021-9517(89)90118-8