Abatement of paraquat contaminated water using solar assisted heterogeneous photo-Fenton like treatment with iron-containing industrial wastes as catalysts

• Published in: Journal of environmental management 2023-01, Vol.325, p.116550-116550, Article 116550
• Main Authors: Pandey, Yamini, Verma, Anoop, Toor, Amrit Pal
• Format: Article
• Language: English
• Subjects: Blast sand; catalysts; chemical oxygen demand; Fly ash; Foundry sand; industrial wastes; Paraquat; Photo-Fenton; pollutants; Red mud; sand; solid wastes; toxicity; waste disposal; wastewater; water pollution
• ISSN: 0301-4797; 1095-8630
• DOI: 10.1016/j.jenvman.2022.116550

Owing to the tremendous increase of chemicals for agricultural practices, the quality of water has degraded significantly and requires inevitable attention. With this in mind, present work aims at treating Paraquat (PQ) contaminated water using Fe containing industrial waste as a catalyst via photo-Fenton treatment. Utilizing the industrially generated Fe rich waste by-products i.e., Fly ash (FA), Foundry sand (FS), Red mud (RM), and Blast sand (BS) as catalysts marks the novelty of the work since this idea of using waste for treating waste serves the dual purpose of environment remediation:first by treating wastewater and second by resolving the issue of solid waste disposal. In the present study, 25 mg/L PQ was subjected to both UV and solar radiations in the presence of FeSO4, FA, FS, RM, and BS as catalysts. The presence of Fe in the catalysts was verified using analytical techniques namely FTIR, FESEM-EDX, and their XRD was also analyzed. The system was further optimized for various parameters and results indicated maximum PQ degradation under UV radiations was attained in the order FeSO4 (73%) > BS (65%) > FS (46%) > RM (37%) > FA (14%) within 60 min which significantly increased with introduction of solar radiations to 83% for Fe salt and 76% for BS justifying the potential of using waste for treating waste. Further, to enhance the real-life utilization of industrial waste, Fe2O3/BS heterojunction (Fe-BS) was synthesized which along with leading to 88% degradation of PQ, also showed 82% COD removal indicating that the catalyst not only degrades the pollutant but also converts it into a lower toxic form. Further, the intermediates formed during the process were analyzed using LCMS. [Display omitted] •Employing industrial solid waste for treating contaminated water.•Utilization of freely available solar energy for water treatment.•Fabricating cost-efficient water treatment system.•Engaging photo-Fenton treatment at natural pH of pollutant.•Analysis of intermediates formed in between the degradation process.