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BACKGROUND BTEX removal is attracting increased attention owing to the detrimental impacts caused to human health, the foremost being neurological impairments. Thus, this study intended to assess the efficiency of zinc–ferrite/V2O5 (ZFV) nanocomposite for photocatalytic degradation of BTEX isomers in aqueous solution. Furthermore, the developed catalyst was magnetically separable, which may reduce the ecological impacts of the catalyst. RESULTS: The ZFV nanocomposite was prepared by a solvothermal process using V2O5 (extracted from treated E‐waste) and zinc–ferrite (synthesized through a chemical co‐precipitation method). The integration of elements in the ZFV nanocomposite was confirmed using powder X‐ray diffraction, Fourier transform infrared, Raman, diffuse reflectance and electrochemical impedance spectroscopies and scanning electron microscopy. Maximum BTEX degradation of 95% was achieved at 50 mg L−1 initial BTEX concentration, 0.50 g L−1 catalyst and pH 3. A minor decrease in the degradation efficiency (10%) of the catalyst was observed at the fifth cycle. The presence of H2O2 increased the degradation efficiency to 98% owing to the prevention of electron–hole recombination, while NaCl (60%), Na2CO3 (63%), NaNO3 (80%) and Na2SO4 (72%) decreased the degradation efficiency due to their hydroxyl scavenging properties. The degradation pathway was elucidated using gas chromatography with mass spectral studies. CONCLUSIONS: The findings of the present study relating to BTEX degradation using the magnetic ZFV nanocomposite and the degradation mechanism throw light on the environmental applications of the ZFV composite. The composite could be an alternative for the remediation of BTEX‐contaminated wastewaters. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: Antibiotics have been identified as significant pollutants owing to their adverse impact on the environment through the development of antibiotic‐resistant bacteria. In a previous study, an e‐waste‐based reduced graphene oxide‐V2O5‐platinum (RGOV‐Pt(1%)) nanocomposite was prepared and subsequently used for the photocatalytic degradation of oxytetracycline (OTC), a tetracycline group of antibiotics. RESULTS: This study aimed to assess the impact of additives such as H2O2, NaCl, Na2CO3, ethanol and persulfate on the photocatalytic degradation of OTC using RGOV‐Pt(1%) nanocomposite. The results showed that the degradation efficiency decreased in the presence of NaCl and Na2CO3 owing to the electron–hole scavenging property of their anions. Low concentrations of H2O2 (up to 10 mmol L–1) increased the OTC degradation efficiency, whereas high concentrations decreased the OTC degradation owing to the quenching of hydroxyl radicals. However, the presence of persulfate increased the OTC degradation efficiency owing to the formation of hydroxyl radicals. Furthermore, the OTC degradation pathway was elucidated using high‐performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS). The study was extended to real pharmaceutical effluent and the degradation efficiency was found to be less for real effluent (87%) in comparison with OTC (99%) in aqueous solution. CONCLUSION: RGOV‐Pt(1%) photocatalyst effectively degraded OTC. An OTC degradation pathway was proposed based on the intermediates formed. The impact of additives was established. Effective real pharmaceutical effluent detoxification was observed. Thus the synthesized RGOV‐Pt(1%) nanocomposite is a hopeful alternative for the removal of antibiotics in contaminated waters and sites. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]