Metal Compounds for Synthetic Chemistry and Energy-Related Catalysis

Monday, January 9, 2012 - 2:00pm
Event Type: 

Molecular Biology Building

Aaron Sadow, Associate Professor, Department of Chemistry

ABSTRACT: The amount of carbon dioxide produced industrially is so significant that an Intergovernmental Panel on Climate Change concluded that currently the only economically viable mitigation strategy is sequestration deep in the ocean. Conversions of CO2 to useful materials (polymers, commodity and fine chemicals) are currently limited by demand. Therefore, new transformations of carbon dioxide to feedstock chemicals could provide improved solutions for reduction of its atmospheric levels. The problem includes separation of carbon dioxide from oxygen and nitrogen in air (CO2 capture), its activation, and its efficient transformation into useful materials. Ideally, inexpensive and abundant materials should be used, both as catalysts and reactants. In this context, we have been exploring reactions of earth abundant zinc compounds with O2 and CO2 and studying the products of those reactions with reductants. From these studies, we have developed catalytic conversions of carbon dioxide to formaldehyde, an important feedstock chemical. We have prepared a reducing zinc hydride that reacts with highly oxidized CO2 to form a zinc formate. That formate reacts with reducing hydrosilanes and hydroboranes to reform the initial zinc hydride and formate, which is then reduced to formaldehyde. Interestingly, the reducing zinc hydride does not react with oxygen. Thus, this catalyst can selectively capture and convert carbon dioxide from air into a useful feedstock chemical.