Surveying Metal Catalysts for Electrochemical Direct Oxidation of Small Organic Compounds

Abstract

Electrochemical degradation of organic molecules is important in wastewater treatment. In addition, the direct oxidation of small organics can be utilized for electrochemical hydrogen production or fuel cell. This study aimed to provide database for various anode catalysts that can degrade organic molecules such as urea, methanol, ethanol, glucose, ammonia, formic acid, acetic acid, oxalic acid in various pH conditions. Pt, Ni, Cu anodes were employed, and the target molecule concentration was 0.3 M. The activity was analyzed by the peak current densities of cyclic voltammetry. The Cu showed activity in the reaction of decomposing glucose and ammonia at pH 14. The Ni was active in ammonia degradation at pH 7, and the Pt was active in oxalic acid oxidation at pH 0. Relevant mechanisms were proposed for these reactions. We suggest Cu-Ni composites for toilet wastewater treatment and Pt for handling anaerobic digestor effluent.