Removal and degradation of triazole fungicides using Ag/PEG-CuO: an efficient adsorbent-catalyst coupling process

Abstract

ABSTRACT In this work, an effective adsorbent-catalyst coupling (ACC) process is proposed and investigated to treat the wastewater polluted with triazole fungicides. In this regard, PEG-CuO as well as Ag particles were prepared and used as the adsorbent and catalyst in the ACC process, respectively. For comparison purposes, Fe3O4 was also utilised as a catalyst. The experiments were conducted to remove penconazole, hexaconazole, and diniconazole (as representative fungicides which were analysed by HPLC-UV). The results show that sole catalysts could not completely remove the triazole fungicides. However, it was found that complete removal and degradation of all fungicides can be obtained using the ACC approach. In the next step, the effects of important operating parameters of the ACC process, i.e. adsorbent load, catalyst load, ratio of catalyst to adsorbent, salt concentration, pH, and operation time were studied. It was found that the optimum condition for all the fungicides was 50/50 ratio of Ag/PEG-CuO, pH of 7, and operating time of 85 min. Finally, the ACC process capability was evaluated for the treatment of five real wastewaters containing triazole fungicides, and the excellent performance of this process was confirmed by observing the complete removal and degradation.