Kinetics study of oxidation of the lignin model compounds by chlorine dioxide
Kinetics study of oxidation of the lignin model compounds by chlorine dioxide
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DOI：
10.1016/j.cej.2013.10.068
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发表时间：
2014-04-01
影响因子：
15.1
通讯作者：
Wang, Shuangfei
中科院分区：
文献类型：
--
作者：
Nie, Shuangxi;Liu, Xinliang;Wang, Shuangfei
在模拟漂白条件下，研究了二氧化氯氧化木质素模型化合物1-（3，4-二甲氧基苯基）乙醇（MVA）的动力学。采用紫外可见分光光度计对二氧化氯与1-（3，4-二甲氧基苯基）乙醇的反应产物进行了表征。提出了可能的反应机理。结果表明，1-（3，4-二甲氧基苯基）乙醇的氯化反应和氧化反应共存。次氯酸是形成可吸附有机卤化物（AOX）的主要原因。根据紫外-可见光谱结果还建立了总体二级速率方程。结果表明：-d[ClO_2]/dt = k '[MVA][ClO_2]，其中k'为观测到的二级速率常数。结果表明，所建立的动力学模型与实验数据具有较好的相关性，可以定量评价二氧化氯氧化1-（3，4-二甲氧基苯基）乙醇的程度。从动力学和机理上探讨了AOX的形成特点和实际意义，为解决纸浆无元素氯（ECF）漂白中的环境污染问题提供了新的思路。(C)2013爱思唯尔有限公司版权所有。
Kinetics study of oxidation of 1-(3,4-Dimethoxyphenyl)ethanol (MVA), a lignin model compounds, with chlorine dioxide under simulated bleaching conditions were investigated. The UV-vis spectrophotometer was employed to characterize the reaction products of chlorine dioxide and 1-(3,4-Dimethoxyphenyl)ethanol. A possible reaction mechanism was proposed. The results showed the chlorination and oxidizing reaction of 1-(3,4-Dimethoxyphenyl)ethanol coexisted. The hypochlorous acid was the main reason to form adsorbable organic halides (AOX). An overall second-order rate equation was also established from UV-vis spectra results. It was shown as: -d[ClO2]/dt = k'[MVA][ClO2], where k' refers to observed second-order rate constants. The results showed the kinetics model correlated well with the experimental data, so the degree of 1-(3,4-Dimethoxyphenyl)ethanol oxidized by chlorine dioxide can be quantitative evaluated based on this model. AOX formation characteristic and practical implications of this work were investigated based on the kinetics and mechanism, which might bring a new door open for resolving the major problems of environmental pollution in elemental chlorine free (ECF) bleaching of pulp. (C) 2013 Elsevier B.V. All rights reserved.