Kinetics of Ultrahigh Temperature Water-Gas Shift Reaction Catalysts Using Simulated Coal-Derived Syngas

• Main Authors: J.-Y. Lin, C.-M. Fang, R.-Y. Chein
• Format: Article
• Language: English
• Published: AIDIC Servizi S.r.l. 2015-09-01
• Series: Chemical Engineering Transactions
• Online Access: https://www.cetjournal.it/index.php/cet/article/view/4586

H2 is currently being widely recognized as a possible energy carrier because of its high energy content and environmental compatibility. H2 production from coal gasification has gained renewed interest because it is recognized as the most abundant fossil fuel. The coal-derived syngas consists mainly of CO and H2. The CO can be further reacted with steam via the water-gas shift reaction (WGSR) to increase the H2 concentration in the syngas. Development of catalyst that can be used at temperature higher than the traditional WGSR operating temperatures is an alternative way to enhance the overall coal-to-H2 thermal efficiency and cost-effective design. With this high temperature catalyst two-stage shift reactors can be reduced to a single reactor and connected at the gasifier exit without the need for syngas cooling. In this study, catalyst performance of WGSR operated in ultrahigh temperature region (750 - 850 °C) was examined experimentally. Using syngas with various compositions and S/C ratios as feedstock, the chemical reaction kinetics of WGSR using 2.5 wt%Pt - 2.5 wt%Ni/5 wt%CeO2/Al2O3 as catalyst can be established based on the experimental data and simple power law. It was found that the prepared catalyst promotes the rate of WGSR when the syngas consists of higher CO concentration and lower CO2 concentration for the operation temperature range studied.