A team led by Prof. Liu Zhongmin at the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, demonstrated carbonylation of propene to isobutyric acid and ethene to propionic acid using zeolites in the presence of water. The study was published in Nature on October 21.
Conventional industrial carbonylation relies on precious-metal catalysts such as rhodium and iridium combined with organic ligands, which involves complex processes, high costs and difficult catalyst-product separation.
Using zeolite pore confinement, the team suppressed competing olefin polymerization and exploited the fact that zeolites are solid catalysts that separate easily from products. Isobutyric acid maintained about 95% product selectivity over 750 hours of continuous operation.
The researchers found that pore architecture controls selectivity: active sites near ten-membered ring openings catalyze propene, while sites in eight-membered-ring cages catalyze ethene.
The team had previously applied zeolites to dimethyl ether carbonylation, enabling large-scale industrial production of anhydrous ethanol. Next steps include process scale-up.
