Oxidative degradation of pentachlorophenol by permanganate for ISCO application.
Potassium permanganate (KMnO4) has been an effective technology for the in situ chemical oxidation (ISCO) of many organic compounds including chlorinated alkanes and alkenes, but it has rarely been applied for oxidizing aromatic organochlorines. This study confirms the ability of permanganate to oxidize an aromatic chlorinated compound, pentachlorophenol (PCP), in an efficient manner at neutral pH. The rate of the reaction between KMnO4and PCP was calculated and the results indicated that the reaction between PCP and permanganate is relatively fast with a second-order rate constant k″ ∼ 30 M-1s-1. Besides the kinetic aspect, the authors identified the main reaction by-products, and proposed a possible reaction mechanism scheme. The general pathway shows the formation of chlorinated intermediates, and ultimately, the complete mineralization to chloride, water, and CO2confirmed by total organic carbon and chloride measurement in solution. Flow-through column experiments, consisting of flushing a PCP-contaminated sandy or natural soil with oxidant, showed the good ability of permanganate to eliminate the pollutant. After 24 h of treatment, 77% and 56% of PCP abatement were obtained for sandy and natural soil, respectively. These findings show the high potential of permanganate for the in situ remediation of aromatic organochlorine contaminated soils.
a Faculty of Sciences, Chemistry and Life & Earth Sciences Department , Holy Spirit University of Kaslik (USEK) , Jounieh , Lebanon.
Roger
http://orcid.org/0000-0002-7942-736X
R
Matta
b UMR HydroSciences Montpellier , Montpellier , France.
Serge
S
Chiron
D017895:Manganese Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D010416:Pentachlorophenol / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D017895:Manganese Compounds; D010087:Oxides; D014874:Water Pollutants, Chemical; C048856:permanganic acid; D010416:Pentachlorophenol
ISCO; aromatic organochlorines; kinetics; pentachlorophenol; permanganate; reaction pathway; soil