桉木CTMP化学预处理废液显色特征及脱色

Color Characteristics and Discoloring of the Effluent from Chemical Pretreatment of Eucalyptus CTMP

利用紫外可见分光光度计对桉木CTMP化学预处理段废液的显色特征进行了表征,使用季铵盐型脱色剂对桉木CTMP化学预处理段废液进行脱色处理,脱色效果良好,可以将酱红色的废液脱色至透明的浅黄色,色度去除率高达98.3%。实验得出的最佳脱色条件为:废液pH值3.0;脱色剂用量1%;快速搅拌时间5min;慢速搅拌时间3min;温度28℃。研究表明,废液中的有色物主要是木素和多酚类物质,而脱色剂的吸附、电荷中和以及架桥作用可以将这些物质去除。

The color characteristic of the effluent from chemical pretreatment stage of Eucalyptus CTMP was studied by UV-Visible spectrophotometer. After a treatment with a synthetic discoloring agent, the color of the effluent changed from dark brown to light yellow and the removal of color unit reached 98.32%. The discoloring conditions were optimized as follows： 28℃,pH 3.0, discoloring agent dosage 1%,5 min of fast agitation and 3 min of slow agitation. The results showed that the colored compounds in the effluent are mainly lignin and polyphenol. The discoloring agent could remove these compounds from the effluent through absorption, charge neutralization and bridging flocculation.