Intensification of conversion of glucose to lactic acid: equilibria and kinetics for back extraction of lactic acid using trimethylamine

Abstract

Alamine 336 is an effective extractant for the recovery of lactic acid from aqueous solutions. An approach for regeneration and product recovery from such extracts is to back extract lactic acid with a water soluble, volatile tertiary amine such as trimethyl amine. Equilibrium data are presented that show near stoichiometric recovery of lactic acid from amine extract. Kinetics of back extraction of lactic acid from Alamine 336 in octanol into aqueous trimethyl amine (TMA) has been presented. Back extraction reaction in a stirred cell falls in Regime 3, extraction accompanied by a fast chemical reaction. The reaction has been found to be zero order in TMA and first order in lactic acid with a rate constant equal to 16.67/s 1. The data reported in this work will be useful in designing the lactic acid recovery system. In thermal regeneration of TMA, 99% of TMA was removed at 200 mmHg from trimethylammonium lactate aqueous solution.