An efficient one pot conversion of glycerol to lactic acid using bimetallic gold-platinum catalysts on a nanocrystalline CeO2 support

摘要

The one pot conversion of glycerol to lactic acid using monometallic Au and Pt as well as bimetallic (Au-Pt) catalysts supported on nanocrystalline CeO2 (n-CeO2) in aqueous solution in the presence of a base and oxygen was investigated. Catalytic performance of the bimetallic catalysts is considerably better than the monometallic ones and is indicative for synergistic effects. The bimetallic system shows excellent activity (TOF=1170h-1 for a batchtime of 20min) with a high selectivity (80%) to lactic acid at 99% glycerol conversion (373K, NaOH to glycerol ratio of 4mol/mol 5bar oxygen). The Au-Pt/nCeO2 catalyst was recycled 5 times in a batch set-up without a significant drop in activity and lactic acid selectivity, indicative for good catalyst stability.