Phosphate Functionalization of CeO2-ZrO2 Solid Solutions for the Catalytic Formation of Dimethyl Carbonate from Methanol and Carbon Dioxide

Phosphate surface groups on CeO2-ZrO2 solid solutions were generated by treating Ce-Zr-hydroxide precursors with phosphoric acid. In the catalytic formation of dimethyl carbonate (DMC) from methanol and CO2, the performance of the P-modified samples was markedly affected relative to that of the unmodified ones: Phosphate treatment caused remarkable changes in the phase composition, acid-base properties, and the ability to form monodentate methoxy intermediates. The DMC yield (1.6%) was successfully improved from 0.24 to 1.6% by phosphate modification of CeO2-ZrO2 (Ce/Zr=4.7, P/Zr=0.13) and by performing the reaction at 170 degrees C and 6.5MPa for 1h.