Patent ID: 8674131
Filing Date: 2014-03-18
Classification: C07B,C07C

Abstract:
1. A process for the preparation of optically pure alkyl esters by esterification of alkali metal and alkaline earth metal salts of carboxylic acid selected from the group consisting of acetates, lactates, salicylates and benzoates, using alcohol and CO 2 and the said process comprising the steps of: i. mixing dehydrated metal carboxylate salt powder with alcohol for period in the range of 15 minutes to 30 minutes with stirring in the range of 500 to 1000 rpm to obtain 5-30% by wt solution of metal carboxylate salt in alcohol; ii. pressurizing the solution as obtained in step (i) with carbon dioxide in the range of 5-60.4 Kg/cm iii. separating the precipitates obtained in step (ii) by filtration; iv. repeating the steps (i) (ii) and (iii) 3 to 4 times; and v. recovering the alkyl ester by distillation with purity in the range of 99.50 to 99.8% by wt. with about 0.03-0.1% by wt of moisture, and recovering the unreacted alcohol and recycling the unreacted alcohol in step iv.