STRUCTURAL CHARACTERISTICS OF LIGNIN AND LIGNIN-CARBOHYDRATE COMPLEX IN RICE STRAW SODA-OXYGEN BLACK LIQUOR
Lignin and lignin-carbohydrate complex(LCC)were isolated and purified from rice straw and soda-oxygen black liquor,respectively.The obtained lignin and LCC preparations were characterized by elemental analysis, Fourier transform infrared spectroscopy and heteronuclear singular quantum correlation(HSQC)NMR.The isolated black liquor lignin(AL)had more oxygen than milled wood lignin(MWL)from rice straw,an oxidation reaction of lignin was happened.The ester linkages of hydroxycynnamic acids were mostly cleaved in soda-oxygen cooking.The HSQC NMR showed p-hydroxyphenyl units were more easily removed from rice straw than guaiacyl and syringyl units.The side-chain structure of lignin was destroyed by soda-oxygen system through the cleavage of β-O-4′ linkages,and novel guaiacyl units with α-carbonyl were generated.Tricin,considered to be incorporated into lignin,was detected in rice straw MWL but was absent in AL.It implies the structure of tricin was destroyed.Phenyl glycoside,benzyl ether and γ-ester were present in LCC of rice straw but the structures were broken after soda-oxygen cooking.
Rice straw Soda-oxygen black liquor Lignin LCC Structural characteristics
Bo Jiang Yu Zhang Lihui Gu Douyong Min Yongcan Jin
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources,Nanjing Forestry University,Nanjing 210037,China
国际会议
第五届制浆造纸新技术国际研讨会(ISETPP)暨第三届国际造纸与环境学术大会(IPEC)
广州
英文
1-4
2016-11-07（万方平台首次上网日期，不代表论文的发表时间）