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Removal of Arsenic Using a Cationic Polymer Gel Impregnated with Iron Hydroxide
Published on: June 28, 2019
Removal of arsenite by simultaneous electro-oxidation and electro-coagulation process
Xu Zhao1, Baofeng Zhang1, Huijuan Liu1
1State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China.
Journal of Hazardous Materials
|September 25, 2010
Summary
This study presents an electrochemical reactor for removing arsenite from water by oxidizing it to arsenate and then using electro-coagulation. The process effectively removes arsenic, with optimal performance at pH 8.
Area of Science:
- Environmental Science
- Electrochemistry
- Water Treatment
Background:
- Arsenite contamination in water poses significant health risks.
- Conventional arsenic removal methods can be inefficient or costly.
Purpose of the Study:
- To develop and evaluate an electrochemical reactor for simultaneous arsenite oxidation and removal.
- To investigate the influence of various ions and pH on the removal efficiency.
Main Methods:
- An electrochemical reactor utilizing dimension stable anode (DSA) and iron plate electrodes was constructed.
- Arsenite was oxidized to arsenate at the DSA electrode.
- Iron ions were electro-generated to form iron oxides for arsenic co-precipitation.
Main Results:
- The electrochemical process effectively removed arsenite by oxidizing it to arsenate, followed by electro-coagulation.
- Calcium (Ca2+) and magnesium (Mg2+) ions enhanced arsenite removal.
- Chloride (Cl-), carbonate (CO3(2-)), silicate (SiO3(2-)), and phosphate (PO4(3-)) ions inhibited removal, with phosphate showing the strongest inhibition.
- Optimal removal efficiency was observed at pH 8.
- Fourier transform infrared spectra analysis suggested removal via adsorption/complexation with generated metal hydroxides.
Conclusions:
- The developed electrochemical reactor offers an effective method for arsenite removal from water.
- Understanding the impact of water matrix ions and pH is crucial for optimizing the process.
- The combined oxidation and electro-coagulation mechanism provides a promising approach for arsenic remediation.
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