Trifluralin-polluted soil treatment using nanosecond pulsed DBD plasma

Cold atmospheric plasma (CAP) was examined as an advanced oxidation process (AOP) for the remediation of trifluralin in soil. Trifluralin is a commonly used herbicide, which is toxic and persistent in soil. CAP experiments were conducted using a cylinder-to-cylindrical-grid reactor layout, driven by a high voltage nanosecond pulse generator. This layout permits plasma discharges to be produced inside the pores of the soil. The initial concentration of the pollutant in a model sandy soil was set 200 mg/kg. The effect of CAP treatment was studied at different operational conditions (e.g. applied voltage and soil type). It was observed that increase of pulse voltage resulted in the increase of degradation efficiency of trifluralin. On the other hand, the use of a field loam soil seemed to decrease the degradation efficiency. In optimum operational conditions, CAP treatment seemed to have excellent performance; a complete removal of the pollutant was observed within a few minutes (3 min < t < 5min). At the same time, the system examined in the current study was proven to be highly-energy efficient.