The Study On Quality Characters Of Biomass In Miscanthus

Miscanthus is a perennial herb, rich in lignocellulose, which has great prospects in the production of bioethanol, biogas, direct combustion for power generation, fodder, medicine and other fields as a new biomass energy plant. A total of ten accessions of Miscanthus were selected to analyze the chemical composition, combustion and pyrolysis properties, which can be provided as a theoretical basis in genetic breeding, exploitation and utilization for Miscanthus, the main results were as follows:1. The content of lignocellulose were determinated by Van Soest, the results showed that the content for these three components was that cellulose was the highest, followed by hemicellulose and lignin between different varieties, the difference were significant among the ten samples in content of cellulose, hemicellulose and lignin.2. The ultrasonic assisted method was used to study the optimum extraction technology of flavonoids in Miscanthus, the optimum extraction technology of flavonoids were as follows: 70% as ethanol concentration, 1:30 as the ratio of raw material to liquid, 70? as extraction temperature, 40 min as extraction time, 3 times as extract series, the content of flavonoids were determinated under this condition, which ranged from 4.16 mg/g to 7.84 mg/g for different varieties, with significant difference; by determining the content of alkaloids, we can come to the conclusion that the content of alkaloids ranged from 0.027 mg/g to 0.053 mg/g, with no significant difference; the volatile oil components in Miscanthus x giganteus(hexaploid), GMG121 and Miscanthus sinensis hybridization were determinated by GC/MS, and 28 kinds of volatile components were identified.3. The results of monosaccharide and FT-IR can be concluded that: xylose was regarded as the main monosaccharide in water-soluble and alkaline-soluble hemicellulose, and the main structure is xylanase, with side chain of arabinose, there was relatively high polymerization degree and less branch in alkaline-soluble hemicellulose; the results of thermogravimetric analysis showed that the pyrolysis process was composed of dehydration, the main pyrolysis and carbonization stages, alkaline-soluble hemicellulose is more difficult to decompose, also with higher thermal stability.4. The results of combustion and pyrolysis properties displayed that the content of C, H, O was comparatively high, the ash content focused on 1.9~3.5%, and the calorific value was 16.56×103 k J/kg, from which we can see that Miscanthus has great combustion characteristics; the results of thermogravimetric analysis demonstated that the pyrolysis process was composed of dehydration, severe weight-loss and slow weight-loss; kinetic parameters showed that Miscanthus x giganteus and GMG121 had relatively high activation energy, which indicated that pyrolysis were more difficult. However, Miscanthus sinensis hybridization had the minimum activation energy, so that its pyrolysis process was more easily compared with the Miscanthus x giganteus and GMG121.