Recovery of acetic acid from pre-hydrolysis liquor of hardwood kraft-based dissolving pulp production process by reactive extraction with triisooctylamine

Scientific Achievement

  Dilution of TIOA played an important role in extracting acetic acid from the PHL. The recovery of acetic acid from the PHL by TIOA was increased from 10.34% to 66.60% with the dilution of TIOA to 20% by decanol at the HAc to TIOA molar ratio of 1. The extraction process was very fast. The acetic acid extraction decreased from 65.13% to 57.34% with the rise of temperature to 50℃ from 20℃. The increase of temperature and pH negatively affected the HAc extraction process from the PHL. The hemicelluloses in the PHL were unaffected on the extraction process of acetic acid.

Significance and Impact

  As the diluent for triisooctylamine (TIOA), decanol had a significant effect on extraction equilibrium. The diluted TIOA can offer a high extraction efficiency, which increased the recovery of acetic acid. The diluted TIOA gave much higher equilibrium distribution coefficient KD than the pure TIOA. Activated carbon pretreatment followed by reactive extraction for recovering HAc can purify PHL for further utilization of sugars in fermentation/biomaterial/bio-based chemicals.

  Acetic acid(HAc) from the pre-hydrolysis liquor (PHL) recovered by reactive extraction with triisooctylamine (TIOA) diluted with decanol. The different factors such as time, temperature, pH, diluation of TIOA with decanol and acid concentration have been studied for the extraction of acetic acid from the activated carbon (AC) pretreated PHL. The characteristics of PHL after acetic acid extraction have also been studied. The hemicelluloses content in the PHL were analyzed on the extraction process of acetic acid.

DOI.org/10.1016/j.biortech.2013.03.164