Comparative study of degradation of toluene and methyl isobutyl ketone(MIBK)in aqueous solution by pulsed corona discharge plasma

• 作者: Jerin Jose Ligy Philip
• 来源期刊: 环境科学学报（英文版）
• 年，卷（期）: 2021,（3）
• 页码范围: 382-396
• 页数: 15页
• 语种: 英文

摘要

Effectiveness of pulsed power plasma for the degradation of two toxic volatile organic com-pounds(VOCs),toluene and methyl isobutyl ketone(MIBK),in aqueous solution was evalu-ated.The plasma degradation of MIBK has been studied for the first time.The influence of initial concentration of target compound,solution pH and scavengers on percentage degra-dation was evaluated.100％removal of 200 mg/L of toluene and MIBK was achieved both in liquid and gaseous phases after 12 and 16 min of plasma treatment,respectively.The first order rate constant of toluene and MIBK degradation(for 200 mg/L each)was 0.421 and 0.319 min-1 respectively when they were treated individually,and these values decreased slightly during degradation of their mixture.MIBK degradation was slower than toluene and it might be due to semi volatile and hydrophilic nature of MIBK.The effect of initial concen-tration of toluene and MIBK showed different degradation patterns.Highest degradation of both the compounds was obtained in neutral pH and in absence of scavengers.·OH radi-cal was the major reactive species involved in their degradation.Their degradation in real environmental matrices showed that removal reduced significantly in secondary effluent due to scavenging of reactive species by various ions and organic matter.The total number of degradation intermediates identified in case of toluene and MIBK was 11 and 14 respec-tively and formate was the one recalcitrant byproduct generated.The degradation pathway of toluene and MIBK involving reactions of reactive oxygen and nitrogen species and reduc-tive species is proposed.