GAS-PHASE ENZYME CATALYSIS USING IMMOBILIZED LIPASE FOR ESTER PRODUCTION

Bench-scale reactors were operated in continuous recycle and single-pa ss modes using immobilized porcine lipase to catalyze gas-phase esteri fication of ethyl alcohol with two carboxylic acids (acetic acid and p ropionic acid). Approximately one order of magnitude increases (over u ncatalyzed reactions) in conversion were achieved; production concentr ations ranged from 0.1 to 0.5 mM in air, and were affected strongly by substrate concentration and acid-induced enzyme inactivation.