Environment
Behnoosh Khataei; Farhad Qaderi; Farzad Mosavat
Abstract
The increase in the number of factories, the industrialization of human life, and the increasing use of industrial paints have caused an increase in dye wastewater and consequent environmental pollution. Discharging wastewater containing the dyes mentioned above, which are often carcinogenic, is a severe ...
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The increase in the number of factories, the industrialization of human life, and the increasing use of industrial paints have caused an increase in dye wastewater and consequent environmental pollution. Discharging wastewater containing the dyes mentioned above, which are often carcinogenic, is a severe threat to living organisms. In this research, a photocatalytic method (as an advanced oxidation method) using zinc oxide nanoparticles was investigated to treat the colored wastewater containing methylene blue. This type of nanoparticle is cheap (based on the used synthesis method), abundant and readily available, and low in toxicity. For this purpose, an evaluation of the optimal ratio between zinc acetate and polyvinylpyrrolidone for the synthesis of zinc oxide nanoparticles was carried out. Furthermore, the simultaneous decreasing and increasing effects of independent parameters (pH, irradiation time, methylene blue concentration, zinc acetate to PVP ratio) on the efficiency of the photocatalytic process and kinetic model were evaluated. The results showed that the best pollutant removal efficiency (91.7%) was obtained using the ratio of zinc acetate and polyvinylpyrrolidone equal to 33.67 in 60 minutes of irradiation time. This result shows that the lower ratio of zinc acetate to polyvinylpyrrolidone indicates higher dye removal.
Environment
Masoud Rabieian; Farhad Qaderi
Abstract
Offshore produced water (OPW), a type of wastewater rich in hazardous compounds such as polycyclic aromatic hydrocarbons (PAHs), requires effective treatment. This study presents a novel methodology utilizing TiO2 nanoparticles, ultraviolet (UV) lamps, and ozonation for the degradation of phenanthrene ...
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Offshore produced water (OPW), a type of wastewater rich in hazardous compounds such as polycyclic aromatic hydrocarbons (PAHs), requires effective treatment. This study presents a novel methodology utilizing TiO2 nanoparticles, ultraviolet (UV) lamps, and ozonation for the degradation of phenanthrene (PHE) from OPW. Various factors including UV lamp power (10W-50W), ozone dose (0.1 mg/L-0.5 mg/L), TiO2 concentration (0.5 g/m²-2.1 g/m²), ethanol fraction (25%-85%), pH (4.5-10.5), PHE initial concentration (5 mg/L-25 mg/L), and treatment time (15 min-45 min) were systematically investigated to understand their impact on PAH degradation in the OPW. The study employs Response Surface Methodology (RSM) for modeling and optimizing PHE removal efficiency. The results contribute to the development of a mathematical model, and through optimization, optimal conditions are proposed to maximize PHE removal efficiency. Experimental implementation of the optimized conditions in a physical model resulted in an impressive 98% PHE removal efficiency. The identified optimal conditions include UV lamp power of 40 W, ozone dose of 0.5 mg/L, TiO2 concentration of 2 g/m², ethanol fraction of 25%, pH of 5.2, initial PHE concentration of 15 mg/L, and a treatment time of 40 min. This optimized approach provides valuable insights for efficient and environmentally friendly treatment of PAHs in OPW, emphasizing on the potential for practical application in soil washing effluent treatment.