A bioinspired heterogeneous catalyst for green and targeted transesterification of ethanol and dimethyl carbonate to ethyl methyl carbonate with high endurance

Abstract

Developing an efficient and sustainable method for producing ethyl methyl carbonate (EMC), a key electrolyte component in lithium-ion batteries, is essential to meet the growing industrial demand and comply with green chemistry principles. Conventional homogeneous processes suffer from excessive sodium-based solid waste and energy-intensive separations, creating an urgent need for a greener alternative. Inspired by the respiratory function of biological lungs, we have rationally designed a novel series of structured flexible ionic polymer catalysts. By introducing polar substrate-sensitive flexible adsorption networks and hydrogen bond-induced selective molecular adsorption active sites, these catalysts enable selective molecular adsorption and activation targeting towards ethanol, making them highly effective and selective with excellent durability. In a mild fixed-bed continuous reaction at 248 K, the EMC yield reaches 67% with a selectivity of over 94%; under reactive distillation conditions, the ethanol conversion exceeds 99.5% with EMC selectivity remaining above 95%. They also demonstrate exceptional operational stability for >3500 h, outperforming all base-triggered transesterification catalysts such as MOF-808. Compared with conventional sodium methoxide, more importantly, our heterogeneous catalysts eliminate 475 t a⁻¹ of solid waste and reduce separation energy consumption and operating costs by 20%, further quantitatively addressing the mandate of Green Chemistry. This study not only establishes a high-efficiency catalytic pathway for EMC production but also provides a generalizable strategy for designing adaptive catalysts aligned with sustainable chemical manufacturing.