THE CARBON-STEAM REACTION AT ELEVATED PRESSURE - FORMATIONS OF PRODUCT GASES AND HYDROGEN INHIBITIONS

被引:83
作者
HUTTINGER, KJ
MERDES, WF
机构
[1] Institut Für Chemische Technik, Universität Karlsruhe, D-7500 Karlsruhe 1
关键词
CARBON-STEAM REACTION; KINETICS; MODELING; HYDROGEN INHIBITION; CARBON MONOXIDE FORMATION; CARBON DIOXIDE FORMATION; METHANE FORMATION;
D O I
10.1016/0008-6223(92)90011-K
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
The reaction between carbon and steam was studied at a temperature of 1000-degrees-C, a total pres-sure of 10 bar and various partial pressures of steam and hydrogen. The concentrations and stabilities of the intermediate surface complexes were measured with the aid of temperature-programmed desorption and transient kinetic experiments. Possible homogeneous formations of carbon dioxide and methane were studied separately. Hydrogen inhibition results from an irreversible reaction: C( ) + 1/2H-2 --> C(H), and two reversible reactions: C( ) + H2O half arrow right over half arrow left C(O) + H-2 and C( ) + H-2 half arrow right over half arrow left C(H)2. Carbon monoxide is formed from a C(O) surface complex: C(O) --> CO + C( ) + approximately approximately C( ), where approximately approximately ( ) represents a dangling carbon atom. Carbon dioxide clearly is a consecutive product of carbon monoxide and thus is not formed at the carbon surface. Methane is formed at the carbon surface, but only from dangling carbon atoms approximately approximately C( ): approximately approximately C( ) H-2 under arrow pointing right approximately approximately CH2 H-2 under arrow pointing right CH4 + C( ).
引用
收藏
页码:883 / 894
页数:12
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