桉木硫酸盐浆漂白D/C及Eo段反应机理的研究

STUDY ON MECHANISMS OF D/C AND E。STAGES DURING E.LEICHOW NO.I KRAFT PULP BLEACHING

本文对桉木硫酸盐浆漂白的氯化段用二氧化氯代替部分氯以及碱处理通氧的机理进行了研究,研究结果表明:用二氧化氯代替部分氯进行氯化,能使浆的KM_nO_4值降低、白度和聚合度提高,通过测定浆中有机结合氯含量、用GPC方法、SEM-EDXA技术和红外光谱分析等数据,证实这是二氧化氯对木素具有选择性氧化作用的结果。碱处理通氧能降低纸浆的KMnO_4值,提高白度,红处光谱分析进一步说明了其机理。

The mechanisms of D/C and Eo stages in D/C-Eo-D sequencehave been studied in this paper.After part of chlorine was substituted witd ClO_2 in chlorinationstage,the permanganate number of pulp was lower and the brightnessand DP of the pulp were higher as compared with the conventionalchlorination.From the data of GPC,SEM-EDXA and IR.and thecontent of organically bound chlorine,is believed that ClO_2 has astrong selectivity in the oxidation of lignin.Compared with convenm-tional alkali extraction,Eo extraction can drop the permanganate num-ber of pulp and raise the brightness.A study with IR has revealedthe mechanism of Eo extraction.