Corona treatment of Eosin Y‐contaminated water by using a dielectric material that covers the ground electrode to avoid spark discharge (causing erosion), reduce charge leakage, and improve the electric field (as stored electrons and charges) was investigated. Elimination of the organic pollutant by gas‐phase discharge above the liquid surface in a point‐to‐plate configuration with multiple needle electrodes was studied. Eosin Y was chosen as model contaminant because of its toxicity and structure that is hard to degrade. Variables such as solution conductivity, dye concentration, pH, air gap, number of needles, and electrode materials were considered. The degree of removal increases with increasing acidity, decreasing concentration, and increasing number of pins.

Elimination of salicylic acid by pulsed corona discharge in a multipin‐plate reactor was investigated. Corona discharge is an alternative technique that produces highly active species such as HO• that degrade salicylic acid. Salicylic acid was totally eliminated in 60 min of treatment with 200 stainless steel needles. Variables such as pH, initial concentration, conductivity, and Na2SO4 dosage were studied to elucidate their influence on salicylic acid elimination. Salicylic acid elimination increased with decreasing pH, initial concentration, and conductivity of the liquid.

The plasma degradation process of Eosin yellow aqueous solution utilizing AC corona discharge generated above liquid with a type of pin to plate by utilizing multiple needles electrodesis investigated the influence of electrodes material and effect of ferrous sulfate on decoloration and the kinetics of process are discussed. The AC corona discharge plasma was generated in the air gap between tip of needles and the water surface. The experimental results indicate that the decoloration rate increases with using stainless steel electrodes and with increasing the concentration of FeSO4. When dye concentration is 10 mg/L with pH of 3, the air gaps were 0.85 cm and the number of pins were 30, the decoloration rate went up to 97% in 60 min.