4-Chloro-3-methylphenol (
c = 2.0 mM), representing amodel pollutant, was oxidized in pressurized hot water
andin supercritical water in a continuous flow system.Potassium persulfate was used as oxidant in concentrationsof 8.0
and 40.0 mM. Contact times (reaction times) were3-59 s, temperatures 110-390

C,
and pressures 235-310bar. A wide temperature range was tested to determinethe range over which potassium persulfate can be usedeffectively. Good oxidation efficiencies for 4-chloro-3-methylphenol were obtained at both oxidant concentrations
and with short contact times at temperatures clearlyunder the critical temperature of water; total organic carboncontent of the effluent was low under optimized conditions.Corrosion, measured as nickel
and chromium concentrations of the effluent, was more severe at oxidant concentrationof 40.0 mM. Sulfate was present in the effluent in highconcentrations. Sulfate is the limiting factor in the use ofpotassium persulfate in wastewater treatment
andrequires further water treatment.