Extraction and Mass Transfer Mechanism of Lactic Acid Ions through a Hollow Fiber Supported Ionic-Liquid Membrane

Abstract

This proposed research examined the c extraction and recovery of lactic acid ions through a hollow fiber supported ionic liquid membrane using counter-current feed and stripping solutions with equal flow rate of 100 mL/min. The initial concentration of lactic acid solution was 0.1 mol/L. The studied parameters such as types of ionic-extractants or carriers, concentrations of acid and base ionic-extractants dissolved in toluene as an organic solvent, and types of the stripping solution were investigated. The results showed that the maximum extraction and the recovery of the lactic acid solution were 52% and 46%, which were performed by using Alamime 336 of 6% (v/v) as a base ionic-extractant and the deionized water as the stripping solution using the operation time of 90 min. Furthermore, the calculated mass transfer coefficients of the extraction and recovery of lactic acid ions through the feed phase (k_f), the liquid membrane phase (k_m) and the stripping phase (k_s) were 1.27 × 10^-4, 3.20 × 10^-3 and 2.22 × 10^-3 cm/s, respectively. According to these values indicating that the diffusion of lactic acid ions through the interface layer between the feed phase and the liquid membrane phase was the mass transfer controlling step of the extraction and recovery of lactic acid.