Preferential Carbon Monoxide Oxidation over Copper-Based Catalysts under InSitu Ball Milling

Insitu ball milling of solid catalysts is a promising yet almost unexplored concept for boosting catalytic performance. The continuous preferential oxidation of CO (CO-PROX) under insitu ball milling of Cu-based catalysts such as Cu/Cr2O3 is presented. At temperatures as low as -40 degrees C, considerable activity and more than 95% selectivity were achieved. A negative apparent activation energy was observed, which is attributed to the mechanically induced generation and subsequent thermal healing of short-lived surface defects. Insitu ball milling at sub-zero temperatures resulted in an increase of the CO oxidation rate by roughly 4 orders of magnitude. This drastic and highly selective enhancement of CO oxidation showcases the potential of insitu ball milling in heterogeneous catalysis.