Purification of organic liquid waste containing sodium dodecylbenzensulfonate and oxalic acid using Y2O3 particles

The chemical method for decontaminating various systems and components contaminated with radioactive materials has the advantage of high efficiency and reduced radiation exposure to workers. However, this method has the disadvantage of generating organic liquid waste during the decontamination process. Electrochemical advanced oxidation processes (EAOP), which decompose organic matter, have been actively studied for treating organic liquid waste. Also, particles have been introduced to improve the efficiency of the EAOP. Therefore, when introducing particles into the EAOP, it is necessary to understand the mechanisms by which organic matter is removed. This study explored the role of Y2O3 particles in the removal of organic matter (sodium dodecylbenzenesulfonate and oxalic acid). The total removal of organic matter was analyzed by considering the precipitation ratio, the particle-induced removal ratio, and the electrochemical oxidation ratio. When Y2O3 particles were added, the organic matter was effectively removed by precipitation and adsorption; however, the removal ratio by the EAOP decreased significantly. Furthermore, when using more than 40 g/L of Y2O3, it was found that the organic liquid waste could be treated without applying electrochemical oxidation through electrolyte concentration-dependent precipitation and particle-induced organic removal reactions.