Extraction of ethanol from fermentation broth using supercritical CO2

Guvenc A., Mehmetoglu U., Calimli A.

3rd International Symposium on High Pressure Chemical Engineering, Zürich, Switzerland, 7 - 09 October 1996, vol.12, pp.463-468 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 12
  • Doi Number: 10.1016/s0921-8610(96)80080-x
  • City: Zürich
  • Country: Switzerland
  • Page Numbers: pp.463-468
  • Ankara University Affiliated: No

Abstract

Extraction of ethanol was studied from both the synthetic ethanol solution and fermentation broth using supercritical CO2 in an extraction apparatus in the ranges of 313 to 333 K and 80 to 160 atmospheres, for varying extraction times. The experimental system consists of mainly four parts: the CO2 storage system, the high pressure liquid pump, the extractor and the product collection unit. Samples were analysed by a gas chromatograph. Effects of temperature, pressure, extraction time, initial ethanol concentration and consecutive solvent feeding on extraction yield were investigated. It was found that increasing the initial ethanol concentration and extraction pressure and decreasing the extraction temperature increased the extraction yield. In addition, it was observed that consecutive solvent feeding affected the extraction yield positively. Using the Box-Wilson optimization method, optimum extraction conditions in a batch system for 15 % (v/v) ethanol solution were found to be 313 K, 133 atmosphere and 30 minutes. Extraction yields were found to be 3 g/l for one step and 10 g/l for three step extraction of fermentation broth.