Summary of Specifications:
Equipment Requirements:
The equipment must be able to analyze polysaccharides, monomeric hexoses and pentoses, acetic and butyric acid, as well as the solvents 1-butanol, ethanol, and acetone. For these purposes a dual unit LC/GC or HPLC/GC is required. 4-8 samples will be run daily.
Description of process as related to LC/GC or HPLC/GC:
We are conducting ABE (acetone, 1-butanol, ethanol) fermentation and require both LC and GC in order to quantify efficiencies of the process, concentration of products in the fermentation broth, and purity of solvents after downstream processing. A variety of different grasses will be used as our feedstock. LC will be used to identify and quantify carbohydrates after the pretreatment and enzymatic hydrolysis, as well as during fermentation to calculate sugar utilization by our bacteria. We intend to have the ability to analyze longer-chained polysaccharides as well as monomeric hexoses and pentoses. Maximum concentration of carbohydrates in liquid will be approximately (200 g/l).
GC will have two purposes. During the first stages of fermentation butyric and acetic acid will be produced in small concentrations (approximately 5-10 g/l). After the acidogenic phase of fermentation, butanol, acetone, and ethanol are produced. Depending on the time elapsed during the solventogenic phase, these solvents will have concentrations ranging from .1 g/l to 25 g/l. Samples will be withdrawn throughout the fermentation and the liquid will contain a mixture of carbohydrates, solvents, and acids. GC will be used to analyze the concentration of these acids and solvents. We haven't established a protocol for diluting this liquid--if it is even necessary.
The second purpose of the GC is to analyze the purity of the solvents (ethanol, butanol, and acetone) after downstream processing (distillation). We anticipate purities of 80%-99%. We are experimenting with different solvents for extracting the butanol from the fermentation broth and will most likely use a longer chained hydrocarbon such as mineral oil.
