Selenium contamination, consequences and remediation techniques in water and soils: A review

Publication Year:

2018

Authors:

Language:

Resource Type:

Journal Article

Summary:

Selenium (Se) contamination in water is a global issue due to its potential health risks. This review explores Se’s chemistry, health threats, and various remediation techniques. It evaluates the pros, cons, and recent advancements of each method, considering experimental conditions and economic factors.

Share to:

Resource Information

Abstract

Selenium (Se) contamination in surface and ground water in numerous river basins has become a critical problem worldwide in recent years. The exposure to Se, either direct consumption of Se or indirectly may be fatal to the human health because of its toxicity. The review begins with an introduction of Se chemistry, distribution and health threats, which are essential to the remediation techniques. Then, the review provides the recent and common removal techniques for Se, including reduction techniques, phytoremediation, bioremediation, coagulation-flocculation, electrocoagulation (EC), electrochemical methods, adsorption, coprecipitation, electrokinetics, membrance technology, and chemical precipitation. Removal techniques concentrate on the advantages, drawbacks and the recent achievements of each technique. The review also takes an overall consideration of experimental conditions, comparison criteria and economic aspects.

Resource Type

Journal Article

Publication Year

2018

Author

Language

Specific Contaminants

University Affiliation

Business Connect Takeaways

The study provides a detailed understanding of the mechanism of fluoride removal by aluminum-based coagulants, specifically AlCl3 and Al13. The results suggest that the defluorination efficiency of these coagulants is influenced by the speciation of aluminum, which affects the formation of aluminum-fluoride complexes and their subsequent removal from the water.

The study highlights the importance of optimizing the dosage and pH of aluminum-based coagulants to achieve maximum defluorination efficiency. The results suggest that excessive dosages of AlCl3 can lead to a decrease in defluorination efficiency due to the hydrolysis of aluminum and the formation of dissolved ions, which can increase the residual aluminum in treated water and reduce the effectiveness of the coagulant.

The study provides insights into the potential use of Al 13 as a more effective coagulant for fluoride removal compared to AlCl3. The results suggest that Al 13 has a higher defluorination efficiency and a wider optimal pH range compared to AlCl3, which could make it a more suitable coagulant for treating water with high fluoride concentrations. However, further research is needed to evaluate the long-term effectiveness and cost-effectiveness of using Al13for fluoride removal.