(733d) Electrocatalysts for the Simultaneous Removal of Nitrate and Ammonia from Wastewater

Authors: 
Botte, G. G., Ohio University
Bagheri Hariri, M., Ohio University
Nitrogen contamination of water resources is considered an environmental and human health issue that causes serious problems e.g., algae bloom, ecological harmful effects like food web changes, and fatal illnesses especially for newborn infants under 6 months [1]. Electro-reduction of NO3- and electro-oxidation of NH3 have attracted lots of attention because they are considered a the straightforward, energy-efficient, environmentally-friendly, and easy to control techniques for NO3-/NH3detoxification [2].

Electrochemical methods for separate removal of NO3- and NH3 has been extensively investigated [1, 3-5]. However, in this work, we demonstrate a new process that addresses both water pollutants simultaneously in an undivided flow cell that leads to a remarkable energy saving in the order of 35-65 % and 90 % less energy per grams of NO3- and NH3 removal, respectively. A new catalyst composition material is introduced to perform both NO3- /NH3 removal simultaneously. The concentration of NO3- andNH3 were measured according to the Environmental Protection Agency (EPA) standards, i.e., an UV-vis spectrophotometric based technique [6], and NH3 Ion Selective Electrode (ISE-THERMO), respectively. Effect of catalyst loading and other process operational conditions on the NO3- and NH3 removal rates were investigated. Findings of this work will be presented at the meeting.

References

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