Application of mixed metal oxide anode for the electro-oxidation/disinfection of synthetic urine: Potential of harnessing molecular hydrogen generation. (1st February 2020)

• Record Type: Journal Article
• Authors: Singla, Jayishnu; Sangal, Vikas K.; Singh, Amanjit; Verma, Anoop
• Is Part Of: Journal of environmental management. Volume 255(2020)
• Publication Date: 2020-02-01
• Subjects: Electro-oxidation -- Mixed metal oxide -- Box behnken design -- Disinfection -- Synergy; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2019.109847
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: The efficacy of electro-oxidation has been checked for the deterioration of synthetic urine (SU) using mixed metal oxide anode along with the potential of harnessing the commercially useful byproduct i.e. molecular hydrogen gas. The results from batch have been used to execute the scale-up studies for the continuous electro-oxidation treatment of SU in a photovoltaic driven reactor. The effect of different operational variables like pH, time, current density and N/Cl ratio on process efficiency was evaluated in terms of %COD removal and specific energy consumption using response surface methodology. The results showed that 87.25% removal in COD and 85.88% in TOC were achieved in 8.8 h. The complete deactivation of E. coli spiked synthetic urine wastewater was achieved in 45 min only. The main strength lies in the demonstration of the significant reduction in treatment time to 6 h by incorporating dual effect i.e. Photo-electrocatalysis. The anode used was proven to be stable and effective even after 100 recycles (207.5 h). The intermediates formed during the treatment process were analyzed through LC-MS. The techno-economic analysis for the proposed technology under optimized conditions was calculated to be 0.85 $/kg of COD removed. Graphical abstract: Image 1 Highlights: Quaternary MMO was used for the electrochemical oxidation/disinfection of synthetic urine. BBD under response surface methodology was used for the parametric optimization. Stability of anodes after 100 recycles was confirmed through XRD and SEM/EDS. Photo-electrocatalysis was performed for assessing the synergistic effect. The potential harnessing of molecular hydrogen generation in a photovoltaic driven electrolytic reactor.