Investigation of boron-doped diamond on porous Ti for electrochemical oxidation of acetaminophen pharmaceutical drug

Abstract

Abstract The electrochemical oxidation of acetaminophen, a kind of potentially dangerous pharmaceutical compound, is conducted on planar and porous Ti/boron-doped diamond (BDD) electrodes to investigate the effect of electrode structure on the electrochemical oxidation behavior. Oxidative peak corresponding to the electron transfer of acetaminophen could be observed around 0.90 V (versus saturated calomel electrode, SCE) on BDD electrodes. The current response from a chronoamperometric curve is proportionally linear in the concentration range from 0 to 3 mmol L − 1 and higher response slope could be obtained on porous Ti/BDD electrode. Complete mineralization can be realized on Ti/BDD electrodes while porous Ti/BDD presents higher COD removal rate and current efficiency compared with planar BDD. The decay kinetics of acetaminophen on BDD electrodes follows a pseudo-first-order behavior, and the corresponding apparent rate constants are 0.208 and 0.344 h − 1 for planar and porous Ti/BDD electrodes at 30 mA cm − 2 . From the detection of hydroxyl radicals, higher generation rate and amount can be obtained on porous Ti/BDD electrode. The enhancement for electrochemical oxidation is related to the porous structure of porous Ti/BDD electrode, which provides more active sites for hydroxyl radicals ( OH) generation. The discrepancy between the COD removal and amount of OH could be explained by the utilization rate of OH.