Electrochemical Behavior of Electrocatalytic Synthesis of Oxalic Acid from Acetylene at Pt Electrode

摘要

Electrocatalytic synthesis of oxalic acid from acetylene has been achieved at Pt electrode. The electrocatalytically synthesized oxalic acid has been characterized by FTIR (Fourier transform infrared spectroscopy) and UV-Vis (UV-Vis spectrophotometry). Influence of electrode material, Na2SO4 concentration, acetone volume fraction, temperature and scan rate have been investigated by CV (cyclic voltammetry). The analysis results show that oxalic acid has been successfully electrocatalytically synthesized from acetylene at the very stable Pt electrode under ambient temperature and pressure, the supporting electrolyte is Na2SO4 (0.5 M) with acetone (2% by volume), the reaction time is 8 h and the conversion efficiency is larger than 20%. The E-a (apparent activation energy) of electrocatalytic oxidation reaction of acetylene at the Pt electrode is 14.42 kJ.mol(-1), the electrocatalytic oxidation process of acetylene is irreversible and under adsorption control. In addition, the reaction mechanism of the electrocatalytic oxidation process of acetylene to oxalic acid has been envisaged successfully based on the principle of adsorption and desorption at Pt electrode surface. It exhibits the excellent electrocatalytic performance of Pt in the electrocatalytic oxidation process of acetylene and heralds more broad potential application prospect of acetylene in chemical industry field.