Application of high voltage electrical discharge plasma in phenolic compounds degradation

Cilj ovog rada bio je istražiti utjecaj hladne plazme na modelnu otopinu fenola te definirati najpovoljnije procesne uvjete za njegovu razgradnju. Modelna otopina fenola tretirana je visokonaponskim plazma pražnjenjem pri frekvenciji 60 Hz, upuhivanim plinovima kisikom i dušikom, naponima 30 i 40 kV te vremenu tretiranja od 30 min. Učinkovitost odabranih procesnih uvjeta ispitana je određivanjem fizikalno-kemijskih parametara: pH, električne provodljivosti i koncentracije fenola. Rezultati pokazuju kako se najuspješnija razgradnja fenola, praćena porastom električne provodljivosti, postiže tretmanom pri pH 10 neovisno o primijenjenom plinu i naponu, dok se u jako alkalnim i kiselim otopinama stupanj razgradnje ne mijenja značajno. Najbolji učinak razgradnje fenola 56,9% pokazao se pri tretmanu napona 40 kV i pH 10 uz upuhivanje kisika.This study aimed to investigate the influence of high-voltage electrical discharge plasma treatment on the model phenol solution as well as on the most favorable process conditions for its degradation. The model phenol solution was treated with high-voltage electrical discharge plasma at a frequency of 60 Hz, injected gases oxygen and nitrogen, voltages of 30 and 40 kV, and treatment time of 30 min. The efficiency of the selected process conditions was evaluated by determining the physico-chemical parameters: pH, electrical conductivity, and phenol concentration. The results show that the most successful decomposition of phenols, followed by an increase in electrical conductivity, is achieved by treatment at pH 10 regardless of the applied gas and voltage, while in strongly alkaline and acidic solutions the degree of phenol decomposition changes is not significant. The best phenol degradation effect of 56.9% was determined in the treatment of 40 kV and pH 10 with oxygen injection