Trichloramine Removal with Activated Carbon Is Governed by Two Reductive Reactions: A Theoretical Approach with Diffusion-Reaction Models.
Trichloramine Removal with Activated Carbon Is Governed by Two Reductive Reactions: A Theoretical Approach with Diffusion-Reaction Models.
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DOI：
10.1021/acs.est.6b05461
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发表时间：
2017-04
影响因子：
11.4
通讯作者：
T. Matsushita;Y. Matsui;Shohei Ikekame;Miki Sakuma;N. Shirasaki
中科院分区：
文献类型：
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作者：
T. Matsushita;Y. Matsui;Shohei Ikekame;Miki Sakuma;N. Shirasaki
通过批式实验和扩散反应模型的理论分析，验证了活性炭去除三氯胺的机理。实验结果表明：（1）三氯胺和游离氯均为反应物，（2）反应物的去除受颗粒内扩散和与活性炭反应的影响，（3）三氯胺的分解受两个不同的还原反应控制。一个还原反应被表示为一级反应：三氯胺与PAC的基面的还原反应，PAC由石墨烯片组成。另一个反应被表示为二级反应：三氯胺与位于基面边缘的活性官能团的还原反应。游离氯与基面和活性官能团竞争反应。事实上，该模型预测成功，即使在实验中与不同的活性炭剂量，与不同的初始三氯胺浓度，并与不同尺寸的活性炭颗粒清楚地证明，在模型中描述的机制是合理的解释与活性炭处理去除三氯胺。
Mechanisms underlying trichloramine removal with activated carbon treatment were proven by batch experiments and theoretical analysis with diffusion-reaction models. The observed values of trichloramine and free chlorine were explained only by the model in which (1) both trichloramine and free chlorine were involved as reactants, (2) the removals of reactants were affected both by the intraparticle diffusion and by the reaction with activated carbon, and (3) trichloramine decomposition was governed by two distinct reductive reactions. One reductive reaction was expressed as a first-order reaction: the reductive reaction of trichloramine with the basal plane of PAC, which consists of graphene sheets. The other reaction was expressed as a second-order reaction: the reductive reaction of trichloramine with active functional groups located on the edge of the basal plane. Free chlorine competitively reacted with both the basal plane and the active functional groups. The fact that the model prediction succeeded even in experiments with different activated carbon doses, with different initial trichloramine concentrations, and with different sizes of activated carbon particles clearly proved that the mechanisms described in the model were reasonable for explaining trichloramine removal with activated carbon treatment.