文献类型：期刊文献

英文题名：Ferrous ion mitigates the negative effects of humic acid on removal of 4-nitrophenol by zerovalent iron

作者：Qin, Hejie[1,2];Yin, Daqiang[1,2];Bandstra, Joel Z.[3];Sun, Yuankui[1,2];Cao, Guomin[1,2,4];Guan, Xiaohong[1,2]

机构：[1]Tongji Univ, Coll Environm Sci & Engn, State Key Lab Pollut Control & Resources Reuse, Shanghai 200092, Peoples R China;[2]Shanghai Inst Pollut Control & Ecol Secur, Shanghai 200092, Peoples R China;[3]St Francis Univ, Dept Math Engn & Comp Sci, Loretto, PA 15940 USA;[4]East China Univ Sci & Technol, Sch Resources & Environm Engn, Shanghai 200237, Peoples R China

年份：2020

卷号：383

外文期刊名：JOURNAL OF HAZARDOUS MATERIALS

收录：;EI(收录号：20193907476812);WOS:【SCI-EXPANDED(收录号:WOS:000502887900094)】；

基金：This work was supported by the National Key R&D Program of China (2016YFE0123700) and National Natural Science Foundation of China (Grants 21777117, and 21522704).

语种：英文

外文关键词：Zerovalent iron; Fe2+; Humic acid; Electron efficiency; Global fitting

摘要：In this study, Fe2+ addition was employed to overcome the negative effects of humic acid (HA) on contaminant removal by zerovalent iron (ZVI), and its feasibility to improve electron efficiency of ZVI was also tested. HA at high concentrations suppressed the removal of 4-nitrophenol (4-NP) by ZVI, while the addition of 0.25-1.0 mM could greatly mitigate this inhibitory effect and enhance 4-NP reduction. Specifically, with a mixed-order model, global fitting results showed that the addition of Fe2+ increased the rate constant from 0.124 x 10(-2) -0.219 x 10(-2) mM/min to 0.227 x 10(-2) -0.417 x 10(-2) mM/min and shortened lag period from 19.7-47.9 min to 8.0-15.2 min for 4-NP removal. The mechanistic investigation revealed this trend could be explained by the following aspects: i) Fe2+ can facilitate the generation of Fe(II)-containing oxides, which can act as an electron mediator or direct electron donor for 4-NP reduction; ii) the presence of Fe2+ could lead to aggregation of HA particles and accordingly reduced its coverage on ZVI surface. But the results of respike experiments indicate that Fe2+ addition did not show remarkable effect on the electron efficiency of 4-NP by ZVI, which should be associated with that Fe2+ was not able to favor the enrichment of 4-NP on ZVI surface.