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

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 0208 and 0344 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 (center dot OH) generation. The discrepancy between the COD removal and amount of center dot OH could be explained by the utilization rate of center dot OH. (C) 2015 Elsevier B.V. All rights reserved.