木质素色团在高得率化学处理及无害漂白中的颜色效果

本文定量研究了木质素色团在Na2SO3处理及H2O2漂白中的颜色效果。研究发现，邻醌和邻酚金属资合物既是Na2SO3处理水质素深色化效果的主要来源，又是影响H2O2漂白木质素浅色化效果的决定因素；共轭羰基对木质素颜色不构成主要影响；Na2SO3处理对木质素引入了相当量的未知颜色源，使木质素发色行为变得更为复杂。

The coloring effect of chromophores of the undissolved lignin by Na_2SO_3-treatment and H_2O_2-bleaching

The quantitative study on coloring effect of chromophores of the undissolvedlignins by Na2SO3-treatment and H2O2-bleaching was completed by analysing theirabsorption at 457nm. It was showed that o-quinone and catechol-metal ion chelatedetermined the coloring effect of the undissolved lignins. 39% and 40% of deep coloringeffect of the undissolved Na2SO3-treated lignin (UTL) came from o-quinone and catechol-Fe3 chelate, respectively, and they made 49% and 33% of contribution to the UTL color.Although decolorization of H2O2-bleaching to lignin was attributed to decrease of the coloringeffect of o-quinone, it still made 37% of contribution to the coloring effect of undissolvedH2O2-bleached lignin. Conjugated carbonyls had little influence on the deep coloring effectand decolorization of lignin. Na2SO3-treatment made the chromophoric behavior of ligninmore complicated. Some change in lignin structure system at which chromophores werepresent took place during Na2SO3-treatment and H2O2-bleaching.