tailieunhanh - Quá trình lên men axit axetic

Tài liệu tham khảo môn công nghệ sinh học về quá trình lên men axit axetic bởi Clostridium Thermoaceticum | Acetic Acid Batch Fermentation Process by Clostridium Thermoaceticum Harumi Veny Masitah Hasan myharumi@ masitahhasan@ Department of Chemical Engineering Faculty of Engineering University of Malaya ABSTRACT Acetic acid was produced through anaerobic batch fermentation process by using Clostridium thermoaceticum as microorganism. The kinetic parameters . pmax Yp s Yx s and the relationship between growth and acetic acid product formation were determined for all environmental effects studied in batch fermentation to establish the optimum condition for this system. The optimum condition obtained from this batch fermentation studies was at pH 6 and temperature of 60C with the maximum product yield Yp s of g acetic acid g glucose and maximum cell yield Yx s of g cell g glucose. The maximum specific growth rate was hour1 achieved at initial glucose concentration of 30 g L. The acetic acid fermentation profile from these studies showed a mix of growth associated and non-growth associated Keywords Acetic acid Clostridium thermoaceticum Single step anaerobic fermentation. 1 INTRODUCTION Presently almost all acetic acid in chemical industry products is produced synthetically. About sixty two percent is produced by the carbonylation of methanol and the rest by the liquid phase oxidation on n-butane and direct oxidation of acetaldehyde Wacker process 1 The major disadvantages of the synthetic process are the need of high temperature and pressure a good agitation the threat of explosion the high cost of catalyst and the dependence on non-renewable sources of raw material crude oil . Hence acetic acid productions to be carried out by biological fermentation mean become more attractive. The production of acetic acid via fermentation by using renewable biomass feedstock has also been studied as alternatives to acetic acid production from petroleum or natural gas feedstock 2 . The fermentation process could reduce the high cost since it uses .