Integrated air stripping and non-thermal plasma system for the treatment of volatile organic compounds from wastewater: statistical optimization

Abstract

This study examined the treatment of toluene and m-xylene from wastewater using integrated air stripping and non-thermal plasma (NTP) reactor system. Toluene and m-xylene concentrations, before and after plasma treatment, were determined using Fourier transform infrared spectroscopy. The performance of the NTP reactor was optimized using the central composite design of the response surface methodology. The optimum discharge gap, applied voltage, and flow rate for the decomposition were found to be 22.34 mm, 15 kV, 3.56 L/min and 20.10 mm, 15 kV, 3.34 L/min for toluene and m-xylene, respectively. Experimental removal efficiencies and model predictions were in close agreement with 1.25 and 2.16% errors for toluene and m-xylene, respectively. The developed model could fit the experimental data with acceptable values of percentage errors.

Keywords:

• Wastewater
• Volatile organic compounds
• Air stripper
• Non-thermal plasma reactor
• Response surface methodology

Acknowledgments

The authors would like to express their sincere appreciation to Universiti Teknologi, Malaysia (UTM) for financial support under exploratory research grant scheme (ERGS); and to the former editor-in-chief of Water Science and Technology, Professor Gustaf Olsson of Lund University, Sweden and Guest Professor to UTM for reviewing the manuscript. Finally, we wish to thank Professor Koichi Takaki of Iwate University Japan for providing the barium titanate used for this research.