Characterization and performance within the WGS reaction of Cu catalysts obtained from hydrotalcites

In large-scale industry, the WGS reaction is the most widely used method for the purification of hydrogen obtained from natural gas. This is a process that hinges on factors such as temperature, pressure, type of catalyst, etc. In this work, copper-based solids were obtained from hydrotalcites, which were characterized through various techniques and evaluated within the WGS reaction at different temperatures. Hydrotalcite-type precursors displayed thermal behaviors that depend on their composition, whereby higher temperatures become necessary for the collapse of the HTLc structure in the solids with higher zinc and aluminum content. The calcination of precursors led to the formation of CuO particles in all the materials, which were more resistant to the reduction processes as the aluminum content augmented. The catalysts were active in the reaction under study with C(0.50)Z(0.25)A(0.25) being the most active material due to the higher content of metallic copper on the surface. The most effective material in terms of metallic copper content present on the surface was C(0.33)Z(0.33)A(0.33), in which the occurrence of CuO was not evinced after its use, in addition to displaying the smallest particle size of Cu-0 as well as, possibly, the existence of CueZn interactions on the surface. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

The study demonstrates the effectiveness of copper-based solid catalysts obtained from hydrotalcites in the water-gas shift reaction. Catalysts with higher zinc and aluminum content require higher temperatures for structural collapse. The material with the highest metallic copper content exhibits the highest activity in the reaction.