Advancing biorefineries: catalytic frontiers in the synthesis and application of glycerol carbonate

Abstract

The global transition towards a circular bioeconomy is limited by the economic challenge of managing low-value byproduct streams. The surplus of crude glycerol as a byproduct from the expanding biodiesel industry threatens its own sustainability. Accordingly, the catalytic valorisation of glycerol into glycerol carbonate has emerged as a pivotal solution to transform this byproduct into a high-value, biodegradable chemical with diverse applications. Transesterification with organic carbonates has attracted considerable attention as an economical and green approach for glycerol carbonate production. However, its industrial viability hinges on developing highly active catalysts and energy-efficient separation processes. Thus, this critical review navigates the recent advancements in this field, offering a unique and performance-driven analysis. This study evaluates homogeneous and heterogeneous systems by employing the space–time yield (STY) to quantitatively compare catalyst efficacy and bridge the gap between literature reports. Furthermore, a critical assessment of downstream separation strategies such as reactive distillation is presented using distribution coefficients and separation factors to benchmark their performance. This study also provides an overall perspective on the entire value chain by linking synthesis and separation to the ultimate applications of glycerol carbonate in green solvents, polymers, and electrolytes. In summary, this work provides important guidelines by identifying key bottlenecks and highlighting the innovations for the conversion of glycerol byproducts in future biorefineries.