Ultrason Sonochem 2017 Nov 15;39:540-549. Epub 2017 May 15.
Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, 51666-16471 Tabriz, Iran.
ZrO-biochar (ZrO-BC) nanocomposite was prepared by a modified sonochemical/sol-gel method. The physicochemical properties of the prepared nanocomposite were evaluated using scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray fluorescence, Fourier transform infrared spectroscopy and Brunauer-Emmett-Teller model. The sonocatalytic performance of ZrO-BC was investigated in sonochemical degradation of Reactive Yellow 39 (RY39). The high observed sonocatalytic activity of the ZrO-BC sample could be interpreted by the mechanisms of sonoluminescence and hot spots. Parameters including ZrO-BC dosage, solution pH, initial RY39 concentration and ultrasonic power were selected as the main operational parameters and their influence on RY39 degradation efficiency was examined. A 96.8% degradation efficiency was achieved with a ZrO-BC dosage of 1.5g/L, pH of 6, initial RY39 concentration of 20mg/L and ultrasonic power of 300W. In the presence of OH radical scavengers, RY39 degradation was significantly inhibited, providing evidence for the key role of hydroxyl radicals in the process. The sonodegradation intermediates were identified using gas chromatography-mass spectroscopy and the possible decomposition route was proposed.