Unexpected effect of buffer solution on removal of selenite and selenate by zerovalent iron
Unexpected effect of buffer solution on removal of selenite and selenate by zerovalent iron
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缓冲溶液对零价铁去除亚硒酸盐和硒酸盐的意外影响
DOI：
10.1016/j.cej.2017.10.025
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发表时间：
2018-02
影响因子：
15.1
通讯作者：
Guan Xiaohong
中科院分区：
文献类型：
--
作者：
Qin Hejie;Sun Yuankui;Yang Hongyi;Fan Peng;Qiao Junlian;Guan Xiaohong
在ZVI反应过程中，许多研究使用缓冲液来控制pH，但缓冲液的影响却鲜有人关注。系统研究了缓冲液对ZVI去除亚硒酸盐(Se(IV))和亚硒酸盐(Se(VI))的影响。研究发现，缓蚀剂的加入会阻碍ZVI的腐蚀，进而影响除Se。在初始pH为4.0时，缓冲液的存在加速了ZVI对Se(IV)的去除，但在≥ 为6.0时，缓冲体系对Se(IV)的去除明显低于无缓冲体系。缓冲液在pH=4.0~10.0时对Se(VI)的截留也有显著的抑制作用。这些影响是由缓冲液引起的，而不是它们对反应过程中pH变化的影响，实验证明，pH效应与整体缓冲液的影响是解耦的。在缓冲体系中，悬浮液的Zeta电位比非缓冲体系中的更负，这表明缓冲液在ZVI表面上有吸附。因此，本研究中观察到的缓冲液的作用主要是由于它在ZVI表面的吸附，这可能会干扰ZVI的腐蚀，以及Se(IV)/Se(VI)在腐蚀ZVI表面的吸附，这是ZVI对Se(IV)/Se(VI)的第一步固定。这些结果表明，需要仔细评估缓冲剂在某些反应中的适用性，以研究动力学和机理。
Many studies used buffers to control pH during the reaction of ZVI, but the effect of buffer solutions received little attention. In this study, the effect of buffers on selenite (Se(IV)) and selenate (Se(VI)) removal by ZVI was systematically investigated. It was found that the addition of buffers can hinder the corrosion of ZVI, and then affect Se removal. Although the removal of Se(IV) by ZVI at initial pH (pH0) 4.0 was accelerated due to the presence of buffer, less Se(IV) was removed in buffered systems than that in unbuffered systems at pH0≥ 6.0. Buffers also dramatically inhibited Se(VI) sequestration at pH04.0–10.0. These effects were caused by the buffers instead of their influence on pH variation during the reaction, evidenced by the experiments that decoupled pH effect from overall buffer influences. The zeta potentials of the suspension in buffered systems were more negative than those in the unbuffered systems, implying the adsorption of buffer onto the ZVI surface. Accordingly, the effect of buffers observed in this study was mainly caused by its adsorption on ZVI surface, which may interfere the corrosion of ZVI as well as the adsorption of Se(IV)/Se(VI) on the surface of corroded ZVI, the first step of Se(IV)/Se(VI) sequestration by ZVI. These results suggest that it requires careful evaluation for the suitability of buffers in some reactions to study the kinetics and mechanisms.
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影响因子：
8.3
作者：
E. Hansson;M. Odziemkowski;R. Gillham
通讯作者：
E. Hansson;M. Odziemkowski;R. Gillham
零价铁还原亚硒酸盐的动力学
影响因子：
1.1
作者：
Yang, Wenjun;Huang, Yuying;Guan, Xiaohong;Li, Lina
通讯作者：
Li, Lina
影响因子：
11.4
作者：
Alowitz, MJ;Scherer, MM
通讯作者：
Scherer, MM
影响因子：
8.8
作者：
E. Lipczynska‐kochany;S. Harms;R. Milburn;G. Sprah;N. Nadarajah
通讯作者：
E. Lipczynska‐kochany;S. Harms;R. Milburn;G. Sprah;N. Nadarajah
DOI：
10.1039/c3en00063j
发表时间：
2014-09
期刊：
Environmental science. Nano
影响因子：
--
作者：
Amanda M. Stemig;T. Do;V. Yuwono;W. Arnold;R. L. Penn
通讯作者：
Amanda M. Stemig;T. Do;V. Yuwono;W. Arnold;R. L. Penn