title: Pentachlorophenol oxidation rates in supercritical water.
abstract: The oxidation rate of pentachlorophenol, [C(6)HCl(5)O] which is used to control termites and as a general herbicide and also as the probable human's carcinogen, was investigated in an isothermal continuous tubular reactor under supercritical water oxidation (SCWO) conditions. The experiments were conducted at a temperature of 400-550 degrees C and a fixed pressure of 25 MPa, with a residence time that ranged from 6 s to 26 s. The conversion of PCP was monitored by analyzing total organic carbon (TOC) on the liquid effluent samples. The initial TOC concentrations of PCP were varied from 0.74 mmol/L to 2.91 mmol/L and the oxygen concentrations were varied from 0.46 mmol/L to 3.52 mmol/L. By taking into account the dependence of the oxidant and TOC concentration on the reaction rate, a global PCP oxidation rate was regressed from the data of 48 experiments, to a 95% confidence level. The resulting activation energy was determined to be 43.56 +/- 1.47 kJ/mol, and the pre-exponential factor was (1.92 +/- 0.46) x 10(2) L(1.16) mmol(-0.16) s(-1). The reaction orders for the PCP (based on TOC) and the oxidant were 0.74 +/- 0.02 and 0.42 +/- 0.05, respectively.
authors: Supercritical Fluid Research Laboratory, Korea Institute of Science and Technology, Seoul, Korea.
authors: Seung Ho
authors: SH
authors: Han
authors: Bambang
authors: B
authors: Veriansyah
authors: Jae-Duck
authors: JD
authors: Kim
authors: Jong-Chol
authors: JC
authors: Lee
mesh_terms: D007700:Kinetics; D009930:Organic Chemicals / Q000737:chemistry; D010084:Oxidation-Reduction; D010416:Pentachlorophenol / Q000737:chemistry*; D013696:Temperature; D014867:Water / Q000737:chemistry*
chemical_list: D009930:Organic Chemicals; D014867:Water; D010416:Pentachlorophenol