Tuesday, April 30, 2013
Exhibit Hall
Lignocellulosic biomass can be a resource for various biorefinery platforms via biological or chemical conversions to produce both commercial commodity products and renewable alternative energy. Pretreatment of lignocellulosic biomass for bio-ethanol production produces a large amount of C3-C6 sugars. C5-C6 sugars such as glucose, xylose and arabinose can be converted into valuable chemicals such as arabinitol, furfural, itaconic acid, levulinic acid, xylitol, and xylonic acid. The main aims of this study are to screen effective conditions of dilute acid pretreatment for obtaining available degradation products from C5-C6 sugars, and to search reasonable conditions for advanced conversion process. Rapeseed stalk (Brassica napus L.) - which is composed of glucan 40.2% and xylan 29.2% - was subjected to organic acid pretreatment under several variable factors, such as catalyst type (sulfuric, oxalic, and malic acids), catalyst concentration (0.5-2%), and pretreatment temperature (130-190°C). After pretreatment, sugars (xylose, arabinose, glucose, galactose, and fructose) and degradation products (furfural, levulinic acid, levoglucosan, xylitol, arabinitol and sorbitol) in the liquid fraction were analyzed by high performance liquid chromatography (HPLC) equipped with RI detector and degradation rates of solid fraction were calculated. Along with each level of separation, final products will be analyzed by a fourier transform-infrared (FT-IR) spectrophotometer, 13C nuclear magnetic resonance (NMR) spectroscopy, gel permeation chromatography (GPC), and elemental analyzer.