Kinetics and Mechanism of Se-Catalyzed Disproportionation of Bisulfite: The Critical Role of Selenosulfate
Kinetics and Mechanism of Se-Catalyzed Disproportionation of Bisulfite: The Critical Role of Selenosulfate
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Se 催化亚硫酸氢盐歧化反应的动力学和机理：硒代硫酸盐的关键作用
DOI：
10.1021/acs.iecr.5b04840
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发表时间：
2016
影响因子：
4.2
通讯作者：
Liu H
中科院分区：
文献类型：
--
作者：
Yang Bentao;Chai Liyuan;Zhu Fangfang;Yan Xu;Xiang Kaisong;Liu Hui;Chai Liyuan;Liu Hui;Liu H;Liu H
硒催化亚硫酸氢盐（HSO 3-）脱硫是一种简便易行、极具潜力的湿法烟气脱硫方法。本文系统地研究了硒催化HSO_3 ~-还原反应的动力学和机理。Se催化的HSO 3-歧化反应相对于HSO 3-和Se浓度呈准一级反应，相对于初始pH值呈零级反应。更重要的是，Se催化HSO_3 ~-反硝化反应的动力学可分为两个阶段，速率控制阶段和加速阶段。在速率控制阶段，反应速率较慢，并形成中间体HSeSO 3-。该中间体是加速HSO_3-还原反应的决定性中间体，因此，它在硒催化过程中起着重要作用。根据实验结果确定了反应动力学方程：r 0 =k1[HSO 3-]0.94[Se]1.13，其中k1 =（10.88 ± 0.04）× 10- 2 M-1.07·min-1。该动力学预测模型与实验数据拟合较好，表明该模型能较好地描述Se催化HSO 3-还原反应的实验动力学数据。
Se-catalyzed disproportionation of bisulfite (HSO3–) is a facile and potential wet flue gas desulfurization. In this paper, the kinetics and mechanism of Se-catalyzed disproportionation of HSO3–were systematically investigated. The Se-catalyzed disproportionation of HSO3–is found to be pseudo-first-order with respect to the HSO3–and Se concentrations, and is zeroth-order with respect to the initial pH value. More importantly, the kinetics of Se-catalyzed disproportionation of HSO3–can be divided into two stages, i.e., a rate-controlling stage and an acceleration stage. In the rate-controlling stage, the reaction rate is slow and the intermediate HSeSO3–forms. This intermediate is decisive to accelerate the HSO3–disproportionation, and thus, it plays an important role in the Se-catalyzed process. Furthermore, a kinetic equation is determined according to the results:r0=k1[HSO3–]0.94[Se]1.13, wherek1= (10.88 ± 0.04) × 10–2M–1.07·min–1. This kinetics prediction model is fitted well with the experimental data, indicating that this model can satisfactorily describe the experimental kinetic data of Se-catalyzed disproportionation of HSO3–.