Water Gas Shift in Microreactors at Elevated Pressure: Platinum-Based Catalyst Systems and Pressure Effects

Abstract

A new lab-scale microstructured reactor was used for investigations on enhancing the H2/CO ratio in synthesis gas from biomass feedstocks via the water gas shift reaction. A model mixture of carbon monoxide, carbon dioxide, water, and hydrogen was used to reproduce the typical synthesis gas composition from dry biomass gasification. Catalyst layers were prepared and characterized; a combined incipient wetness impregnation and sol–gel technology was applied. The catalytic activities of Pt/CeO2 and Pt/CeO2/Al2O3 films were determined at temperatures of 400–600 °C and pressures of up to 45 bars. Increased pressure leads to higher values of CO conversion and to increased formation of hydrocarbons (CH4, C2H6, etc.) and coke. Methane is the main by-product, and coke formation was attributed to the catalytic activity of peripheral reactor components.