Efficient recovery of bio-based 1,2,4-butanetriol by using boronic acid anionic reactive extraction

Abstract

Abstract Effective isolation of 1,2,4-butanetriol (BT) from the fermentation broth with low BT concentration was achieved based on anionic reactive extraction with a combined extractant consisted of boronic acid carrier and trioctylmetylammonium Aliquat® 336 (A336) dissolved in the organic phase. The influence of various diluents, pH values, the ratio of phenylboronic acid derivatives (PBAD) to BT (αPBAD/BT), and A336 to BT (βA336/BT) on extraction property was investigated in detail. For model BT solutions, satisfactory extraction efficiency of 92% was obtained under the conditions of αPBAD/BT\xa0=\xa01.5, βA336/BT\xa0=\xa02, with dichloromethane as a diluent. Aqueous hydrochloric acid solutions were employed to strip BT from the organic phase. For actual fermentation broth, the extraction and stripping efficiency under the optimum conditions were 74% and 69%, respectively. Besides, compared with the original fermentation broth, 1,2,4-butanetriol has been concentrated by 4.6 times with the reactive extraction coupled hydrolysis.