Submitted to: Biotechnology for Fuels and Chemicals Symposium Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 5/4/2005
Publication Date: 5/4/2005
Citation: Karcher, P., Ezeji, T.C., Qureshi, N., Blaschek, H.P. 2005. Butanol extraction from fermentation broth: mathematical equations. Biotechnology for Fuels and Chemicals Symposium. Paper No. 6-57.
Technical Abstract: Butanol, a major product of acetone butanol ethanol (ABE) fermentation, is toxic to the cells of Clostridium acetobutylicum/C. beijerinckii that produce it. The maximum concentration of butanol in a batch reactor does not exceed 20 g/L, thus hampering recovery of this solvent due to a higher boiling point than water. In order to make butanol recovery energy efficient, extraction of butanol using an organic solvent was sought. In order to avoid cell growth inhibition and achieve an efficient recovery, four different processes were considered and mathematical equations were developed. These four processes include: 1) Staged extraction from cell free broth (extraction without concurrent production, EW/OCP); 2) staged extraction from whole broth (extraction with concurrent production, EWCP); 3) differential extraction from cell free broth (EW/OCP); and 4) differential extraction from whole broth (EWCP). In all four cases, flow directions were counter current. For these four processes, the effect of various parameters on butanol extraction will be presented.