Removal of salicylic acid from aqueous solution by mediated electrochemical oxidation and photoelectrochemical oxidation process

• Main Authors: Ming-Chieh Kuo, 郭明傑
• Other Authors: Wei-Lung Chou
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/24856d

碩士 === 弘光科技大學 === 職業安全與防災研究所 === 103 === Salicylic acid (SA) is a small phenolic compound whose therapeutic properties on human health have been described; its derivatives (SADs) are widely present in natural waters and many industrial waste streams, with highly relevant pollutants because of their toxicity and relatively low biodegradability. This study investigated the removal of salicylic acid from wastewater by paired photo electrochemical oxidation system, in which employing metal redox mediators with high redox potential for MEO process and UV assisted photo electrochemical oxidation. The tasks also included the comparisons of efficiencies in different processes and determine the optimum conditions. Based on the results, the feasibility of this study by paired photo electrochemical oxidation process in situ was evaluated. The research was divided into two parts: First, the electrogeneration of Ce (IV) remove salicylic acid from the Ce (III) by the anodic MEO process. The optimum current density, Ce (III) concentration, nitric acid concentration, temperature were found to be 10 mA cm-2, 0.01 M, 0.4M ,313K. Under these conditions, the salicylic acid concentration of aqueous salicylic acid solutions decreased by more than 99 %. In second part, the synergistic effect of combination process of MEO and PEO were a paired photo electrochemical oxidation system for the removal efficiency of salicylic acid. The optimum current density, Ce (III) concentration, nitric acid concentration, temperature, oxygen flow rate, and UV irradiation intensity were found to be 15 mA cm-2, 0.01 M, 0.4M, 313K, 500 cm3 min-1 and 1.2 mWcm-2. In this operating condition, the removal of salicylic acid in the anode and cathode were up to 85% and more than 65%, respectively.