Simultaneous redox conversion and sequestration of chromate(VI) and arsenite(III) by iron(III)-alginate based photocatalysis

被引：59

作者：

Zhang, Weifang ^{[1
,2
]}

Liu, Feng ^{[1
]}

Sun, Yonggang ^{[1
,2
]}

Zhang, Jing ^{[1
,2
]}

Hao, Zhengping ^{[2
]}

机构：

[1] Chinese Acad Sci, Key Lab Environm Nanotechnol & Hlth Effect, Res Ctr Ecoenvironm Sci, Beijing 100085, Peoples R China

[2] Univ Chinese Acad Sci, Natl Engn Lab VOCs Pollut Control Mat & Technol, Beijing 101408, Peoples R China

来源：

APPLIED CATALYSIS B-ENVIRONMENTAL | 2019年 / 259卷

基金：

中国国家自然科学基金;

关键词：

Fe(III)-alginate hydrogel beads; Chromium; Arsenic; Simultaneous redox conversion; Photocatalysis; ACID-MINE DRAINAGE; HEXAVALENT CHROMIUM; ARSENIC REMOVAL; IRON; REDUCTION; OXIDATION; AS(III); CR(VI); PH; ADSORPTION;

D O I：

10.1016/j.apcatb.2019.118046

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Multiple heavy-metal ions (e.g. Cr(VI) and As(III)) normally co-exist in acid wastewater, making the wastewater treatment complicated. Herein, the synergistic redox conversion and removal of Cr(VI)/As(III) were effectively achieved by applying iron(III) cross-linking alginate hydrogel beads (Fe-SA) as photocatalyst under simulated sunlight. Results show that not only 100% of the Cr(VI)/As(III) redox conversion was obtained in 150 min at pH 3.0, but also the removal efficiency of the transformed products (Cr(III) and As(V)) was greatly enhanced to above 80% in a wide pH range of 3-7. The (CO2-)-C-center dot radicals, produced by the ligand to metal charge transfer (LMCT) excitations on Fe-SA, together with the phtocatalysis-generated Fe(II), was responsible for the Cr(VI) reduction. Meanwhile, (OH)-O-center dot originating from (CO2-)-C-center dot mainly contributed to the As(III) oxidation, as confirmed by electron paramagnetic resonance and the by-product of CO2. Moreover, Fe-SA composite presented excellent reusability and performance in treatment of Cr(VI)/As(III) in real waters.

引用

页数：11