Synthesis and determination of ozone levels in the ozonated waste cooking oils by dielectric barrier discharge (DBD) plasma

Converting the waste cooking oil into the ozonated oil is one way to reduce environmental pollution. The synthesis of ozonized oil can be done with plasma technology using the dielectric barrier discharge (DBD) plasma method. This research aims to synthesize the ozonized waste cooking oil using DBD plasma and determine the ozone levels therein. Plasma was generated using argon and oxygen gas at a flow rate ratio of 0.6 L/min:0.4 L/min that connected to an AC voltage of 5 kV. The treatment was done with time variations of 15, 30, 45, and 60 min. The results of the treatment were investigated with UV-Vis spectrophotometer and ozonation titration. Furthermore, the reactive species present in plasma were analyzed with optical emission spectroscopy (OES). After the treatment, the waste cooking oil has a clearer color than before treatment. The absorption peaks of waste cooking oil and treatment oil were observed at 240 and 273 nm. Meanwhile, the highest ozone concentration of 0.197 ppm was achieved for 30 min plasma treatment. The results conclude that the waste cooking oil is able to be converted to the ozonated oil by DBD plasma generated in this study with high efficiency.