The use of response surface methodology for modeling and optimizing of p-nitrophenol contaminated water treatment process conducted by the non-thermal plasma discharge technology

In the realm of industrial development, a variety of organic pollutants, including petroleum compounds, have emerged as persistent environmental concerns due to their non-degradable nature. To effectively address this issue, plasma technology has garnered significant attention as a promising approach for wastewater treatment, offering the capability to eliminate a wide spectrum of contaminants. This research capitalizes on Response surface methodology (RSM) to explore the independent and combined effects of key factors such as initial concentration, pH, applied voltage, and time on the degradation of a specific pollutant known as PNP, utilizing non-thermal discharge plasma technology. The outcomes of this investigation unveiled several noteworthy trends. Enhancing the initial pH, applied voltage, and reaction time while reducing the initial concentration exhibited a positive influence on the removal efficiency. Additionally, the study examined the interactions among these variables, revealing both antagonistic and synergistic effects. Specifically, antagonistic relationships were observed between initial concentration and initial pH, initial concentration and applied voltage, as well as applied voltage and time. On the other hand, a synergistic effect was noted between initial concentration and time. By employing an optimization approach, the optimal conditions for achieving PNP degradation were determined to be as follows: an initial concentration of 50 mg/L, pH of 9.7, applied voltage of 13.75 kV, and a reaction time of 8 min, resulting in an impressive removal efficiency of 96.503%. The findings of this study underscore the immense potential of non-thermal discharge plasma technology and the utilization of RSM in advancing the optimization of advanced oxidation processes for effective wastewater treatment.