The goal of this project is to develop efficient ceria catalysts for recycling two categories of waste chemicals: CO<sub>2</sub> from fossil fuel combustion, and bio-derived alcohols such as methanol (wood alcohol) and glycerol (a byproduct of biodiesel refining). Conventionally, organic carbonates are produced indirectly using toxic and corrosive chemicals such as phosgene. This was necessitated because the direct conversion of dimethyl carbonate (DMC) from methanol and CO<sub>2</sub>, as shown above, is only product favored as a low temperature process while the activation barrier for this reaction is very high on existing catalysts. We are currently measuring the activation barrier for this reaction on ceria, a known catalyst for this process, as well as on modified ceria surfaces. We are using information gained from reaction kinetics from our modified ceria surfaces to improve our understanding of the reaction mechanisms, while using computational studies of reaction mechanisms to inform our surface modification experiments. Current heterogeneous catalysts used for this reaction provide conversion efficiency of only around 1%. Improvements of catalytic conversion to around 10% is believed to be enough to make this reaction pathway industrially viable for the production of carbonates from carbon dioxide and waste alcohols.
Funding support: Nebraska Center for Energy Sciences Research