The Removal of As(V) from Drinking Waters by Coagulation Process using Iron Salts

Authors: M. Donmez, F. Akbal

Abstract:

In this study arsenate [As(V)] removal from drinking water by coagulation process was investigated. Ferric chloride (FeCl3.6H2O) and ferrous sulfate (FeSO4.7H2O) were used as coagulant. The effects of major operating variables such as coagulant dose (1–30 mg/L) and pH (5.5–9.5) were investigated. Ferric chloride and ferrous sulfate were found as effective and reliable coagulant due to required dose, residual arsenate and coagulant concentration. Optimum pH values for maximum arsenate removal for ferrous sulfate and ferric chloride were found as 8 and 7.5. The arsenate removal efficiency decreased at neutral and acidic pH values for Fe(II) and at the high acidic and high alkaline pH for Fe(III). It was found that the increase of coagulant dose caused a substantial increase in the arsenate removal. But above a certain ferric chloride and ferrous sulfate dosage, the increase in arsenate removal was not significant. Ferric chloride and ferrous sulfate dose above 8 mg/L slightly increased arsenate removal.

Keywords: Arsenic removal, coagulation, ıron salts, drinking water.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1073685

References:

[1] V.K. Sharma, M. Shon, "Aquatic arsenic: Toxicity, speciation, transformations, and remediation," Environment International, 2009, vol. 35, pp. 743-759.
[2] J.A.G. Gomes, P. Daida, M. Kesmez, M. Weir, H. Moreno, J.R. Parga, G. Irwin, H.M. Whinney, T. Grady, E. Peterson, D.L. Cocke, "Arsenic removal by electrocoagulation using combined Al-Fe electrode system and characterization of products," Journal of Hazardous Materials, 2007, vol. B139, pp. 220-231.
[3] P.R. Kumar, S. Chaudhari, K.C. Khilar, S.P. Mahajan, "Removal of arsenic from water by electrocoagulation," Chemosphere, 2004, vol. 55, pp. 1245-1252.
[4] S.Y.T Choong, T.G. Chuah, Y. Robiah, G. Koay, I. Azni, "Arsenic toxicity, health hazards and removal techniques from water: an overview," Science Direct Desalination, 2007, vol. 217, pp. 139-166.
[5] J.M. Triszcz, A. Porta, F.S.G. Einschlag, "Effect of operating conditions on iron corrosion rates in zero-valent iron systems for arsenic removal," Chemical Engineering Journal, 2009, vol. 150, pp. 431-439.
[6] S.R. Wickramasinghe, B. Han, J. Zimbron, Z. Shen, M.N. Karim, "Arsenic removal by coagulation and filtration: comprasion of groundwaters from the United States and Bangladesh," Desalination, 2004, vol. 169, pp. 231-244.
[7] H. Guo, Y. Li, K. Zhao, "Arsenate removal from aqueous solution using synthetic siderite," Journal of Hazardous Materials, 2010, vol. 176, pp. 174-180.
[8] V.K. Gupta, V.K. Saini, N. Jain, "Adsorption of As(III) from aqueous solutions by iron oxide-coated sand," Journal of Colloid and Interface Science, 2005, vol. 288, pp. 55-60.
[9] T.V. Nguyen, S. Vigneswaran, H.H. Ngo, J. Kandasamy, "Arsenic removal by iron oxide coated sponge: Experimental performance and mathematical models," Journal of Hazardous Materials, 2010, vol. 182, pp. 723-729.
[10] Y.Y. Chang, K.H. Song, J.K. Yang, "Removal of As(III) in a column reactor packed with iron-coated sand and manganese-coated sand," Journal of Hazardous Materials, 2008, vol. 150, pp. 565-572.
[11] C.S. Jeon, K. Baek, J.K. Park, Y.K. Oh, S.D. Lee, "Adsorption characteristics of As(V) on iron-coated zeolite," Journal of Hazardous Materials, 2009, vol. 163, pp. 804-808.
[12] K. Tyrovola, E. Peroulaki, N.P. Nikolaidis, "Modeling of arsenic immobilization by zero valent iron," European Journal of Soil Biology, 2007, vol. 43, pp. 356-367.
[13] A. Jain, V.K. Sharma, O.S. Mbuya, "Removal of arsenite by Fe(VI), Fe(VI)/Fe(III), and Fe(VI)/Al(III) salts: Effect of pH and anions," Journal of Hazardous Materials, 2009, vol. 169, pp. 339-344.
[14] M. Bilici Baskan, A. Pala, "A statistical experiment design approach for arsenic removal by coagulation process using aluminum sulfate," Desalination, 2009, vol. 254, pp. 42-48.
[15] M. Bilici Baskan, A. Pala, "Determination of arsenic removal efficiency by ferric ions using response surface methodology," Journal of Hazardous Materials, 2009, vol. 166, pp. 796-801.