Abstract: Electrocatalytic activity of Ti/PbO₂ anode on oxidation degradation of p-methylphenol was studied by linear sweeping voltammetry and galvanostatic electrolysis in an electrolytic cell without diaphragm. Electrocatalytic oxidation mechanism of p-methylphenol was explored by HPLC analysis of p-methylphenol and its degradation intermediates in anodic oxidation processes. The results indicat that Ti/PbO₂ electrode can electrocatalyze the oxidation of p-methylphenol and its intermediates in the solution effectively. The conversion of p-methylphenol and the removal ratio of oganic carbon reached 74.31% and 61.8% in 3.0 h, respectively, in the electrolyzing process with constant current 50 mA/cm² in the solution containig initial concentration 2 mmol/L of p-methylphenol at 25 ℃. The pathway of electrooxidation degradation of p-methylphenol may be p-methylphenol→p-hydroxybenmethanol→p-hydroxybenzaldehyde→p-hydroxybenzoic acid→hydroquinone→benzoquinone→maleic acid→oxalic acid, and the final product is CO₂. The electrooxidation reactions of hydroquinone and maleic acid are the rate determining steps.

Key words: p-Methylphenol, Electrooxidation, Electrocatalysis, Reaction mechanism