Journal
CHEMICAL ENGINEERING JOURNAL
Volume 375, Issue -, Pages -Publisher
ELSEVIER SCIENCE SA
DOI: 10.1016/j.cej.2019.122051
Keywords
Wastewater; Arsenic; Electrochemical adsorption; Birnessite; Redox reactions
Categories
Funding
- National Key Research and Development Program of China [2017YFD0801000, 2018YFD0800304]
- National Natural Science Foundation of China [41425006, 41571228, 41877025]
- Fundamental Research Funds for the Central Universities [2662018JC055, 2662015JQ002]
- US Department of Energy, Office of Basic Energy Sciences, Division of Chemical, Biological and Geological Sciences [DE-FG0286ER13622.A000]
- Chinese Scholarship Council fellowship
Ask authors/readers for more resources
Manganese oxides have been extensively investigated for arsenic (As) adsorption from aqueous solution. However, the effect of electrochemical redox reactions on the adsorption performance and underlying mechanism remain elusive. Herein, birnessite was used for electrochemical adsorption of As from mining wastewater at a constant cell voltage, and the effect of cell voltage and the continuous use (without desorption) performance of birnessite electrode were also evaluated. At 1.2 V for 24 h, the concentrations of total As (As(T)) and As(III) in wastewater decreased from 3808.7 to 73.7 mu g L-1 and 682.8 to 21.4 mu g L-1, respectively. The As (T) removal ratio increased with increasing cell voltage and reached 98.1% at 1.2 V, which was higher than that at open circuit (84.1%). The Mn2+ concentration also significantly decreased in wastewater during As adsorption. The high potential of birnessite anode and the generation of H2O2 on cathode facilitated As(III) oxidation, and the electrochemical redox reactions of birnessite contributed to the enhancement of As(T) removal. The application of cell voltage reversal could improve the utilization rate of birnessite electrodes by dissolution-recrystallization during continuous use, and the As(T) removal ratio was increased from 73.5% to 85.1% after five cycles of voltage alteration. The present work indicates that birnessite is a promising absorbent for the electrochemical adsorption of As from real wastewaters.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available