Electrochemical Destruction of Waste Lubricants Using Diamond-Coated Electrodes

Electrochemical oxidation with boron-doped, diamond-coated electrodes could potentially be applied to treat radioactively contaminated oils. Accordingly, a feasibility study was performed using two representative, non-radioactive oils (a cutting fluid and a hydraulic oil). The process was shown to remove between 92 and 99% of the organic material in an alkaline suspension of the cutting fluid, with 87% of the added organic carbon being recovered as carbonate. A further test demonstrated that the oxidation could be maintained during periodic addition of oil to the electrochemical cell. It was found that the hydraulic oil would not form a stable emulsion and separated from the electrolyte, effectively removing it from the active area around the electrodes; as a result the hydraulic oil resisted oxidation. This limitation is not insurmountable and the results of these initial trials were considered to be sufficiently encouraging that further development is ongoing at AWE with the aim of developing a process that could be applied to radioactively-contaminated oils within a Controlled Area (Contamination).© 2003 ASME