Transition Metal Catalysts for the Ambient Temperature Destruction of Organic Wastes Using Peroxydisulfate

Destruction of the organic components of hazardous or mixed waste has been demonstrated in a process known as Direct Chemical Oxidation (DCO). This technology, developed over the last six years at Lawrence Livermore National Laboratory (LLNL), is an aqueous-based process which mineralizes almost all organics through oxidative destruction by peroxydisulfate. The process typically operates at 80–100 °C but there are obvious advantages to lowering this operating temperature to near ambient for the treatment of volatile materials, or for situations where heating the waste is impractical (e.g., large area decontamination of soil). For the purposes of quantifying transition metal catalytic activity in a prototype DCO system, the Destruction and Removal Efficiencies (DRE’s) for the oxidation of several model organic substrates in acid peroxy-disulfate solutions have been measured. Results are presented for the enhancement of destruction rates of ethylene glycol, 1,3-dichloro-2-propanol, tributyl phosphate, and a “real world” waste surrogate using catalysts such as ionic Ag, Cu, Co, and Fe.