Enhanced arsenite removal from water by Ti(SO4)2 coagulation

Yuankui Sun; Gongming Zhou; Xinmei Xiong; Xiaohong Guan; Lina Li; Hongliang Bao

doi:10.1016/j.watres.2013.05.028

Enhanced arsenite removal from water by Ti(SO₄)₂ coagulation

Yuankui Sun, Gongming Zhou, Xinmei Xiong, Xiaohong Guan, Lina Li, Hongliang Bao

Research output: Contribution to journal › Article › peer-review

84 Scopus citations

Abstract

Coagulation with the conventional coagulants such as ferric and aluminum salts is not efficient for As(III) removal. In this study Ti(SO₄)₂ was employed for enhanced As(III) removal and Fe₂(SO₄)₃ was used as a reference. The removal efficiencies of As(III) by Ti(SO₄)₂ at pH 4.0-9.0 were greater than that by Fe₂(SO₄)₃ by 7.39-32.8% and 3.14-48.1% for coagulants dosed at 8.0mg/L and 12.0mg/L, respectively. The advantage of Ti(SO₄)₂ over Fe₂(SO₄)₃ for As(III) removal was more significant at lower pH, which may be ascribed to the more negatively charged surface of Ti(IV) hydroxides. To reduce As(III) from 0.2mg/L to 10μg/L, the necessary dosage of Ti(SO₄)₂ was only ~50% of that of Fe₂(SO₄)₃. The adsorption capacity of As(III) on Ti(IV) hydroxides formed in-situ was greater than that on Fe(III) hydroxides formed in-situ by ~100mg/g and several times higher than the adsorption capacities of TiO₂ for As(III) reported in the literature. The presence of competing anions, silicate, phosphate and humic acid, did not alter the advantage of Ti(SO₄)₂ over Fe₂(SO₄)₃ for arsenite removal. Replacing partial Ti(SO₄)₂ with Fe₂(SO₄)₃ (same dosage) and applying them sequentially could achieve similar As(III) removal efficiency as single Ti(SO₄)₂, which could thus reduce the chemical cost. The extended X-ray absorption fine structure (EXAFS) spectroscopy indicated that As(III) form bidentate binuclear surface complexes with Ti(IV) hydroxides as evidenced by As(III)-Ti bond distances of 3.33-3.35Å. This study revealed that Ti(SO₄)₂ may be an alternative coagulant for efficient As(III) removal.

Original language	English
Pages (from-to)	4340-4348
Number of pages	9
Journal	Water Research
Volume	47
Issue number	13
DOIs	https://doi.org/10.1016/j.watres.2013.05.028
State	Published - 1 Sep 2013
Externally published	Yes

Keywords

Arsenic
Coagulation
Complexation
Ferric sulfate
Titanium sulfate

Access to Document

10.1016/j.watres.2013.05.028

Cite this

@article{f8d167d644ae45cfabaefe50ede5f30f,

title = "Enhanced arsenite removal from water by Ti(SO4)2 coagulation",

abstract = "Coagulation with the conventional coagulants such as ferric and aluminum salts is not efficient for As(III) removal. In this study Ti(SO4)2 was employed for enhanced As(III) removal and Fe2(SO4)3 was used as a reference. The removal efficiencies of As(III) by Ti(SO4)2 at pH 4.0-9.0 were greater than that by Fe2(SO4)3 by 7.39-32.8\% and 3.14-48.1\% for coagulants dosed at 8.0mg/L and 12.0mg/L, respectively. The advantage of Ti(SO4)2 over Fe2(SO4)3 for As(III) removal was more significant at lower pH, which may be ascribed to the more negatively charged surface of Ti(IV) hydroxides. To reduce As(III) from 0.2mg/L to 10μg/L, the necessary dosage of Ti(SO4)2 was only \textasciitilde{}50\% of that of Fe2(SO4)3. The adsorption capacity of As(III) on Ti(IV) hydroxides formed in-situ was greater than that on Fe(III) hydroxides formed in-situ by \textasciitilde{}100mg/g and several times higher than the adsorption capacities of TiO2 for As(III) reported in the literature. The presence of competing anions, silicate, phosphate and humic acid, did not alter the advantage of Ti(SO4)2 over Fe2(SO4)3 for arsenite removal. Replacing partial Ti(SO4)2 with Fe2(SO4)3 (same dosage) and applying them sequentially could achieve similar As(III) removal efficiency as single Ti(SO4)2, which could thus reduce the chemical cost. The extended X-ray absorption fine structure (EXAFS) spectroscopy indicated that As(III) form bidentate binuclear surface complexes with Ti(IV) hydroxides as evidenced by As(III)-Ti bond distances of 3.33-3.35{\AA}. This study revealed that Ti(SO4)2 may be an alternative coagulant for efficient As(III) removal.",

keywords = "Arsenic, Coagulation, Complexation, Ferric sulfate, Titanium sulfate",

author = "Yuankui Sun and Gongming Zhou and Xinmei Xiong and Xiaohong Guan and Lina Li and Hongliang Bao",

year = "2013",

month = sep,

day = "1",

doi = "10.1016/j.watres.2013.05.028",

language = "英语",

volume = "47",

pages = "4340--4348",

journal = "Water Research",

issn = "0043-1354",

publisher = "Elsevier Ltd",

number = "13",

}

TY - JOUR

T1 - Enhanced arsenite removal from water by Ti(SO4)2 coagulation

AU - Sun, Yuankui

AU - Zhou, Gongming

AU - Xiong, Xinmei

AU - Guan, Xiaohong

AU - Li, Lina

AU - Bao, Hongliang

PY - 2013/9/1

Y1 - 2013/9/1

N2 - Coagulation with the conventional coagulants such as ferric and aluminum salts is not efficient for As(III) removal. In this study Ti(SO4)2 was employed for enhanced As(III) removal and Fe2(SO4)3 was used as a reference. The removal efficiencies of As(III) by Ti(SO4)2 at pH 4.0-9.0 were greater than that by Fe2(SO4)3 by 7.39-32.8% and 3.14-48.1% for coagulants dosed at 8.0mg/L and 12.0mg/L, respectively. The advantage of Ti(SO4)2 over Fe2(SO4)3 for As(III) removal was more significant at lower pH, which may be ascribed to the more negatively charged surface of Ti(IV) hydroxides. To reduce As(III) from 0.2mg/L to 10μg/L, the necessary dosage of Ti(SO4)2 was only ~50% of that of Fe2(SO4)3. The adsorption capacity of As(III) on Ti(IV) hydroxides formed in-situ was greater than that on Fe(III) hydroxides formed in-situ by ~100mg/g and several times higher than the adsorption capacities of TiO2 for As(III) reported in the literature. The presence of competing anions, silicate, phosphate and humic acid, did not alter the advantage of Ti(SO4)2 over Fe2(SO4)3 for arsenite removal. Replacing partial Ti(SO4)2 with Fe2(SO4)3 (same dosage) and applying them sequentially could achieve similar As(III) removal efficiency as single Ti(SO4)2, which could thus reduce the chemical cost. The extended X-ray absorption fine structure (EXAFS) spectroscopy indicated that As(III) form bidentate binuclear surface complexes with Ti(IV) hydroxides as evidenced by As(III)-Ti bond distances of 3.33-3.35Å. This study revealed that Ti(SO4)2 may be an alternative coagulant for efficient As(III) removal.

AB - Coagulation with the conventional coagulants such as ferric and aluminum salts is not efficient for As(III) removal. In this study Ti(SO4)2 was employed for enhanced As(III) removal and Fe2(SO4)3 was used as a reference. The removal efficiencies of As(III) by Ti(SO4)2 at pH 4.0-9.0 were greater than that by Fe2(SO4)3 by 7.39-32.8% and 3.14-48.1% for coagulants dosed at 8.0mg/L and 12.0mg/L, respectively. The advantage of Ti(SO4)2 over Fe2(SO4)3 for As(III) removal was more significant at lower pH, which may be ascribed to the more negatively charged surface of Ti(IV) hydroxides. To reduce As(III) from 0.2mg/L to 10μg/L, the necessary dosage of Ti(SO4)2 was only ~50% of that of Fe2(SO4)3. The adsorption capacity of As(III) on Ti(IV) hydroxides formed in-situ was greater than that on Fe(III) hydroxides formed in-situ by ~100mg/g and several times higher than the adsorption capacities of TiO2 for As(III) reported in the literature. The presence of competing anions, silicate, phosphate and humic acid, did not alter the advantage of Ti(SO4)2 over Fe2(SO4)3 for arsenite removal. Replacing partial Ti(SO4)2 with Fe2(SO4)3 (same dosage) and applying them sequentially could achieve similar As(III) removal efficiency as single Ti(SO4)2, which could thus reduce the chemical cost. The extended X-ray absorption fine structure (EXAFS) spectroscopy indicated that As(III) form bidentate binuclear surface complexes with Ti(IV) hydroxides as evidenced by As(III)-Ti bond distances of 3.33-3.35Å. This study revealed that Ti(SO4)2 may be an alternative coagulant for efficient As(III) removal.

KW - Arsenic

KW - Coagulation

KW - Complexation

KW - Ferric sulfate

KW - Titanium sulfate

UR - https://www.scopus.com/pages/publications/84879021895

U2 - 10.1016/j.watres.2013.05.028

DO - 10.1016/j.watres.2013.05.028

M3 - 文章

C2 - 23764585

AN - SCOPUS:84879021895

SN - 0043-1354

VL - 47

SP - 4340

EP - 4348

JO - Water Research

JF - Water Research

IS - 13

ER -

Enhanced arsenite removal from water by Ti(SO₄)₂ coagulation

Abstract

Keywords

Access to Document

Other files and links

Fingerprint

Cite this