Response of Chemical Changes of the Wood Compositions to Heat-treatment
To investigate the essential chemical modifications involving the polymeric constituents in wood on heat treatment, extractive-free wood meal of Black locust (Robinia pseudoacacia) was treated at 30％ moisture content under the oxygen and nitrogen environment, respectively. Significant chemical variations of wood components after heat treatment were observed by means of CPMAS-13C-NMR, FTIR-ATR, DRUV and elemental analysis. The results showed that, signals at 153 ppm decreased significantly and new signals at 148 ppm were introduced after heat treatment, and those variations became intense with the presence of oxygen. The β-O-4 structure and the aliphatic side chains in lignin cleaved and new conjugated double bonds, such as α,β-unsaturated ketone and α-C=O, can be formed during heat treatment. Phenols were transformed to quinone structure and α, β-unsaturated ketone and α-C=O in lignin were found increased when subjected to heat treatment at the presence of oxygen. The hydrogen and oxygen element reduced, whereas the C-content increased slightly after heat treatment. Dehydration and elimination as well as condensation reactions occured in both the carbohydrates and the lignin during heat treatment.
Robinia pseudoacacia heat-treatment lignin extractives
Yao CHEN Yong-ming FAN Jian-min GAO Rui-ping Wu
College of Material Science and Technology, Beijing Forestry University，Beijing, 100083, P.R.China
国际会议
南京
英文
522-528
2010-10-22（万方平台首次上网日期，不代表论文的发表时间）