화학공학소재연구정보센터
Chemical Engineering Communications, Vol.192, No.10-12, 1621-1635, 2005
Selective oxidation of alcohols by redox molecular sieves
High-throughput synthesis and screening of libraries consisting of redox zeolites and molecular sieves have been developed for the selective oxidation of 2-butyl-5-hydroxymethyl-imidazole to the corresponding aldehyde in the liquid phase. Libraries consisting of 96 catalysts were prepared and screened for catalytic activity using high-throughput software, robotics, reactor, and screening technologies. The integrated synthesis and screening workflow allowed similar to 5000 samples to be screened in less than one month. Promising hits identified in the high-throughput primary screens were successfully scaled up and optimized in conventional laboratory test units. Best results have been obtained with doubly or triply doped mesoporous sieves containing both an impregnated and framework-substituted metal. PtBi-doped framework-substituted V-MCM-41 redox mesoporous sieves were found to be efficient catalysts for aerobic oxidation under relatively mild reaction conditions (100-150 degrees C, 15-400 psi air, 4-10 h reaction time). MIBK\H2O\t-BuOH mixtures were identified as efficient solvent systems for this reaction. Isolated yields confirm high selectivities of more than 90% with quantitative conversions. Spent catalysts were shown to be fully regenerable by high temperature calcination in air.