Monday, May 2, 2011
Grand Ballroom C-D, 2nd fl (Sheraton Seattle)
The analysis of carbohydrate concentration in liquor samples is important in the research and development of cellulosic ethanol. Currently the industry standard for carbohydrate analysis is the use of an HPLC (high pressure liquid chromatograph) with a Pb ++ cation exchange column and a refractive index detector (RID). This system is reliable and robust but the RID is non-specific for carbohydrates and the method requires long run times (42 minutes/sample). There is an alternative technique, Ion Chromatography with Pulsed Amperometric Detection (HPAEC-PAD). This system, along with a new commercially available column, provides excellent separation of monosaccharides present in biomass hemicellulose hydrolysate liquors. The PAD is more specific and selective for carbohydrates than HPLC, and run times can be reduced to 12 minutes. We will present data that compares the perfomance of the HPAEC-PAD method with the traditional HPLC-RID method, including calibration samples and hydrolyzate samples produced from different methods (pre-treatment, enzymatic hydrolysis, 4% acid hydrolysis) on both systems. We will specifically compare the chromatography, peak resolution, run times, and analysis results (e.g. final measured carbohydrate concentrations) from the two methods.