Harnessing Mg–Zn–Ce Ternary Mixed Oxide Nanostructure-Based Catalysts for Efficient Carbonylation of Glycerol with CO<sub>2</sub> to Glycerol Carbonate
Piyusa Priyadarsan Pattanaik, Mallikarjun Geekuri, Kore Ranjithkumar, Gunniya Hariyanandam Gunasekar, N. Lingaiah
Abstract
Conversion of CO 2 to chemicals and fuels is one of the key approaches for reducing carbon emissions and achieving carbon neutrality. In this regard, the direct carbonylation of glycerol (GLY) and CO 2 into glycerol carbonate (GLC) is an important and promising conversion as it converts the two wastes into a value-added product. However, the high kinetic barrier associated with the thermodynamic stability of CO 2 challenges the development of highly productive and durable catalytic systems for this direct coupling reaction. Herein, ternary metal oxide catalysts consisting of Mg–Zn–Ce with truncated nanopolyhedral structures are prepared by the coprecipitation method with improved acidity/basicity and surface oxygen vacancy properties. The prepared mingled mixed oxide nanocatalysts are found to be highly efficient in converting GLY/CO 2 to GLC, achieving an excellent GLY conversion of about 90% with an unprecedented GLC productivity of 4.64 mmol g cat –1 h –1 using the 10Mg/10Zn/CeO 2 catalyst in the presence of 2-cyanopyridine dehydrant at 150 °C under 4.0 MPa of CO 2 pressure. Studies on the catalyst structure-activity relationship revealed that the synergistic cooperation between the surface oxygen vacancies and acid–base sites together with the surface area played a key role in enhancing the CO 2 carbonylation activity. Therefore, this work provides a promising strategy to design nanostructured ternary oxide catalysts for the construction of highly efficient CO 2 carbonylation catalysts.