Separation of ethanol from fermentation broth during the production of fuel ethanol

CHED 440

Rebecca Ann Hill, rhill@centenary.edu, Centenary College of Lousiana, 9322 Stonebriar Circle, Shreveport, LA 71115 and Clifford E. George, Swalm School of Chemical Engineering, Mississippi State University, P.O. Box 9595, Mississippi State, MS 39762.
In this study, a hydrophobic, polypropylene, hollow fiber membrane module model G543 manufactured by Liqui-Cel was used to evaluate the effectiveness of the perstraction of ethanol from a mixture of ethanol and water. The fiber membrane had an outer diameter of 300µm and an inner diameter of 200µm. Solutions of ethanol in water at concentrations of 10, 7.5, and 5 weight percent ethanol were used as the simulated fermentation broth. 1-octanol, tri-n-butylphosphate, 2-ethyl-1-butanol, and water were used as the solvents. Water proved to be the most effective and the least toxic solvent. Fick's Law diffusion coefficients were determined for ethanol diffusing from the shell side to the lumen side of the membrane. Experimental results indicate that as the flow rate of solvent on the lumen side increases, the diffusion coefficient decreases. Also, the dependence of temperature on diffusion coefficient of the ethanol-water solvent system was studied at 22, 30, and 35 degrees Celsius. The diffusion coefficient varied from a minimum value of 3.58E-11 m2/s at 22 degrees Celsius to a maximum of 1.38E-09 m2/s at 35 degrees Celsius over the range of concentrations and flow rates tested.
 

Undergraduate Research Poster Session: Chemical Education
11:00 AM-1:00 PM, Monday, March 26, 2007 Hyatt Regency Chicago -- Riverside Center, Poster

Division of Chemical Education

The 233rd ACS National Meeting, Chicago, IL, March 25-29, 2007