Reactive extraction of lactic acid with Alamine 336 in the presence of salts and lactose

TLDR

The study examined reactive liquid–liquid extraction of lactic acid with Alamine 336 in toluene from 40 g dm⁻³ aqueous solutions and investigated the influence of salts and lactose. Experiments were conducted at 25 °C and 50 °C using 20 % and 40 % v/v Alamine 336 in toluene, measuring distribution coefficients, and at 25 °C with aqueous phases containing varying concentrations of sodium chloride and lactose.

Abstract

Abstract The reactive liquid‐liquid extraction of lactic acid with Alamine 336 dissolved in toluene from aqueous solutions of 40.0 g dm −3 lactic acid was examined. Experiments were performed at 25 and 50°C for two amine concentrations of 20% and 40% v/v in toluene, and distribution coefficients were determined. Calculations based on the stoichiometry of the reactive extraction and the equilibria involved indicated that more lactic acid is transferred to the organic phase than would be expected from the stoichiometry of the reaction. The influence of salts and lactose on the lactic acid extraction was also investigated. Experiments were carried out at 25°C using, as aqueous phases, solutions of lactic acid (40.0 g dm −3 ) which contained sodium chloride and/or lactose at different concentrations. Results indicated that the extraction of lactic acid with Alamine 336 dissolved in toluene is not affected by lactose. If sodium chloride is present, less lactic acid is extracted by the organic phase and hydrochloric acid co‐extraction is observed.