Remediation of water contaminated with diesel oil using a coupled process: Biological degradation followed by heterogeneous Fenton-like oxidation

• Published in: Chemosphere (Oxford) 2017-09, Vol.183, p.286-293
• Main Authors: Chen, Yuan, Lin, Jiajiang, Chen, Zuliang
• Format: Article
• Language: English
• Subjects: Acinetobacter - metabolism; Acinetobacter venetianus; Advanced oxidation process; Biodegradation, Environmental - drug effects; Biological Oxygen Demand Analysis; Diesel oil; Fenton-like; Hydrogen Peroxide - pharmacology; Iron; Oxidation-Reduction; Recalcitrant compounds; Waste Water - chemistry; Water - chemistry; Water - metabolism; Water Pollutants, Chemical - chemistry; Water Pollutants, Chemical - metabolism; Water Purification - methods
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2017.05.120

The treatment of a synthetically prepared wastewater containing diesel oil has been investigated using combined treatment schemes based on the biological treatment followed by an advanced oxidation process. 78% of diesel oil was degraded by Acinetobacter venetianus in 96 h, while the removal efficiency of chemical oxygen demand (COD) in the aqueous phase was only 56.8%, indicating that degraded metabolites existed in solution. To solve this problem, a Fenton-like system consisting of nanoscale zero-valent iron (nZVI) and hydrogen peroxide was used for further oxidation of the metabolites after biodegradation. Results showed that the total COD removal increased from 56.8% to 89% under the optimal condition. In addition, effects of initial pH (2.0–9.0), ZVI dosage (0–2.0 g L-1), hydrogen peroxide (H2O2) dosage concentration (0–15 mmol L-1) and temperature (298–308 K) on the treatment efficiency of the combined process were studied. Scanning electron microscopy (SEM) demonstrated that changes to the surface of nZVI occurred. GC-MS revealed that the degraded metabolites were mineralized practically by nZVI/H2O2 system. The results points towards the potential of Fenton-like oxidation as a short post-treatment after a biological process for the treatment of organic pollutants in wastewater. •Diesel oil was removed by biodegradation and Fenton oxidation.•78% diesel oil was degraded by Acinetobacter venetianus in 96 h.•Total COD removal increased from 56.8% to 90% by nZVI.•It is a potential remediation for hard degradable contaminants.