Hydrogen production and purification from the water–gas shift reaction on CuO/CeO2–TiO2 catalysts

The present study evaluates the use of copper catalysts supported on ceria and/or titania for water–gas shift reaction (WGSR). The effect of metal-support interaction coupled with structural properties such as surface area and oxidation state favor the conversion of CO to CO2 and the hydrogen formation. The strong copper–ceria interaction promotes the good performance of the CuCe system, while the poor interaction between titania and copper disadvantaged the performance of the CuTi catalyst. However, the addition of ceria into the titania support hampers the transformation of anatase to rutile phase, facilitates the reduction of metal species and favors the metal-support interaction. The combined results of these features are a better performance for CuCeTi catalyst compared to the system only containing ceria or titania. The catalytic evaluation has revealed that both CuCeTi and CuCe catalysts produce significant amounts of H2 during the WGSR process and favor a H2/CO ratio close to 2. The use of these catalysts for WGSR, especially at high temperature (HT-WGSR), showed good performance, fulfilling the goal of CO in reducing levels for hydrogen fuel cell applications.