Determination of solubilization isotherm in micelles of non-ionic surfactant L62 for butanol extraction

摘要

Earlier studies with extractive butanol fermentation using non-ionic surfactant L62 showed significant increase in butanol titer by 50-125%. Butanol was further separated from fermentation broth using L62 in a cloud point extraction system. The present work was undertaken to determine the solubilization of butanol in L62-water system. Experiments were conducted to study the effect of different parameters on butanol extraction efficiency. Optimum conditions i.e. 3% L62 (v/v) with 4% (v/v) butanol concentration at 45 degrees C for 30 min resulted into extraction efficiency of 40.8% (w/w). The Langmuir isotherm was fitted and isotherm parameters were found to be m = 129.87 (mol/mol) and n = 0.308 (L/mol). Langmuir isotherm with estimated parameters was used to predict the surfactant concentration to extract butanol with desired efficiency. Predicted and experimental results were in close agreement (96% accuracy). Thus, Langmuir model can be successfully used to design the cloud point extractor and predict the extraction efficiency/surfactant concentration for L62-butanol-water system with great accuracy. (C) 2019 Elsevier B.V. All rights reserved.