Selective combinatorial catalysis; challenges and opportunities: the preferential oxidation of carbon monoxide

This work presents a knowledge-based approach for the selection of catalysts along with an experimental methodology to be used with high throughput and combinatorial catalytic experimentation. As a demonstration of this methodology, new results on the activity and selectivity of different catalysts for the preferential oxidation of CO are presented. Two families of catalysts were selected on the basis of existing literature results, one family consisted of Pt and Pd supported on alumina and titania promoted with ceria, and the other family of the same metals interdispersed in various oxides. The activity of an array of up to 50 samples is studied using in situ infrared thermography (IRT). The materials that showed the highest activity in the IRT studies were selected for further evaluation in a parallel reactor with 10 microreactors and then in a single recycle reactor. The results show that titania supported Pt catalysts promoted with ceria show the highest activity and selectivity for the PROX reaction. Thus the selective combinatorial approach, which is a restricted approach of combinatorial catalysis, can lead quickly to new catalytic results.