JFET_V4_N2_RP3 Amit Keshav Kailas L. Wasewar Shri Chand Hasan Uslu Ismail Inci Journal on Future Engineering and Technology 2230 – 7184 4 2 41 49 Reactive Extraction, Propionic Acid, Thermodynamics, Temperature, Extractants, Diluents Temperature effect is an important subject of study in the reactive extraction process in view of operating temperature and back extraction/regeneration step. Usually in industrial scale, for production of carboxylic acids, fermentor operates in the temperature range of 303 to 313 K. Thus, an extractant can be considered as good, only if it could operate efficiently in this operating range. The study, thus aims two objectives. (1) To find the effect of temperature on extraction of the propionic acid (2) Whether temperature swing extraction/regeneration can be employed for recovery of the acid. Three types of extractants: tri-n-butylphosphate, tri-n-octylamine and Aliquat 336 were used in different diluents and the thermodynamics of extraction process was discussed in terms of enthalpy and entropy of reaction. Extraction of propionic acid using TOA in different diluents resulted in negative values of enthalpy and entropy. Thus, the reactive extraction process is exothermic in nature and decrease in entropy is obtained. Aliquat 336 in 2-octanol shows the similar behavior as TOA in different diluents but the entropy and enthalpy values were lower, thus by suggesting not so high exothermic nature of the extraction process and not so strong acid Aliquat 336 complexation as acid TOA complexation. Two departures in the normal trend were observed when Aliquat 336 was used in oleyl alcohol and TBP was used in MIBK. In both cases an increase in Ke was observed upto a certain temperature and whereupon a decrease was observed. The effect of temperature was correlated in terms of the heat of transfer from organic to aqueous phase (ÄH ). It was found that the higher the ÄH for a particular diluent, higher is the temperature effect. November 2008 - January 2009 Copyright © 2009 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=521