Arsenic removal by iron oxide coated sponge: Experimental performance and mathematical models

• Published in: Journal of hazardous materials 2010-10, Vol.182 (1), p.723-729
• Main Authors: Nguyen, Tien Vinh, Vigneswaran, Saravanamuthu, Ngo, Huu Hao, Kandasamy, Jaya
• Format: Article
• Language: English
• Subjects: Adsorption; Applied sciences; Arsenic; Arsenic - isolation & purification; Chemical engineering; Computational efficiency; Drinking water; Drinking water and swimming-pool water. Desalination; Exact sciences and technology; Ferric Compounds - chemistry; Groundwater; Groundwaters; Iron oxide coated sponge (IOCSp); Iron oxides; Isotherms; Mathematical models; Modeling; Models, Theoretical; Natural water pollution; Performance evaluation; Pollution; Sponges; Thermodynamics; Water treatment and pollution
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2010.06.094

Millions of people worldwide are at risk from the presence of arsenic in groundwater. In this study, adsorption equilibrium and long term experiments were carried out to evaluate the performance of iron oxide coated sponge (IOCSp) in arsenic removal. It was found that maximum adsorption capacity of IOCSp for As(III) and As(V) calculated by Sips isotherm was 4.2 and 4.6 mg/g of IOCSp, respectively. A filter packed with small amount of 25 g IOCSp maintained a consistent arsenic removal efficiency of 95% from synthetic solution containing arsenic concentration of as high as 1000 μg/L. This produced a throughput volume of 153 and 178 L of water containing As(III) and As(V), respectively before any need for regeneration or disposal of IOCSp. IOCSp could be regenerated by washing it with NaOH solution. The dynamic (column) adsorption kinetics were successfully predicted by the Thomas and Nikolaidis modified models.