ABSTRACT
Municipal solid waste leachate dissolved with nitrates of Cr, Pb, and Cu was investigated using a supercritical water oxidation process in this study. The destruction efficiency of chemical oxygen demand increased with the higher temperature and longer reaction time. A first-order expression applied for chemical oxygen demand was determined with a pre-exponential factor of 318 s–1 and activation energy of 58 kJ/mol. Recovery efficiency of Cr, Pb, and Cu from initial solution into solid product increased with the higher temperature and longer reaction time. X-ray diffraction of solid products showed that the metal species were found to be Cu2O, HCrO2, and CaCO3 at temperature 400°C, while the structure were identified as CuO, Cr2O3, PbCrO4, and CaCO3 at temperature 500°C.