Sustainable catalysts for methanol carbonylation

Abstract

Methanol carbonylation is the most important process for manufacturing C2 molecules from methanol. The present industrial carbonylation has been proven to be the most successful process on economical grounds. However, there is a request to develop more sustainable and ‘green’ processes to overcome the inherent drawbacks. Well-designed cross-linked copolymers were prepared and used as support for the simultaneous immobilization of rhodium and iodide species. The resulting catalyst was proven to be highly active in CH₃I-free methanol carbonylation and methyl acetate was the main product. Approximately 90% of methanol was converted after a two-hour reaction time at 120 °C under a CO pressure of 3.0 MPa. The immobilization strategy of the active species works efficiently and the present methanol carbonylation catalyst shows good recyclability. After regenerating the catalyst twice over a fifteen-batches test, the catalyst keeps an acceptable activity. The process based on the present catalyst is evidently a promising sustainable methanol carbonylation.