Application of RuO2/Ni foam electrodes for remediation of ibuprofen in soil matrix-the effect of electrokinetic parameters.

Pharmaceuticals and personal care products (PPCPs) are an extraordinary and diverse group of chemicals used in veterinary medicine, agriculture, and for human health and cosmetics care. They are considered emerging contaminants and have raised great concern in recent years. Among the PPCPs, ibuprofen (IBP) is one of the most known non-steroidal anti-inflammatory drugs, which has been found at a high concentration in irrigation water in the USA and showed harmful effect for organisms. This study examined IBP degradation performance by an electrokinetic process coupled with 24-96 cm2 of RuO2/Ni foam (RN) electrodes applied 1-3 V cm-1 potential gradient for 5-9 days. The electroosmosis permeabilities (k e) and the treatment efficiency of IBP increased from 1.5 × 10-4 to 1.8 × 10-4 cm2 V-1 s-1 and from 65.4 to 78.4%, respectively, as the potential gradient increased from 1 to 3 V cm-1. The k e values also increased with electrode area, but it was much less insignificant than that of the potential gradient. Prolonging the treatment time and increasing the electrode area only enhanced the IBP remediation efficiency by a trivial amount. The degradation mechanism was more critical for IBP remediation than was the electrokinetic (EK) removal mechanism. A cost analysis revealed that processing fluid accounted for 84.1-87.6% of the operation cost. The electrode characteristics and the treatment mechanism are also discussed. This study confirmed that the IBP-contaminated soil was successfully remediated by electrokinetic process coupled with RN electrodes.