Facile Preparation of ZnO Nanocatalysts for Ozonation of Phenol and Effects of Calcination Temperatures

Abstract

ZnO nanoparticles were synthesized through a facile route and were used as ozonation catalysts. With the increase of calcination temperature (150-300 o C), surface hydroxyl groups and catalytic efficiency of asobtained ZnO decreased remarkably, and the ZnO obtained at 150 o C showed the best catalytic activity. Compared with ozonation alone, the degradation efficiency of phenol increased above 50% due to the catalysis of ZnO-150. In the reaction temperatures range from 5 o C to 35 o C, ZnO nanocatalyst revealed remarkable catalytic properties, and the catalytic effect of ZnO was better at lower temperature. Through the effect of tertbutanol on degradation of phenol and the catalytic properties of ZnO on degradation of nitrobenzene, it was proposed that the degradation of phenol was ascribed to the direct oxidation by ozone molecules based on solidliquid interface reaction.

Understanding of phenolic compound retention mechanisms on PES-UF membrane

“…There are currently several standard methods for treating effluents containing phenolic compounds, which can be divided into two main categories: 8 destructive methods, namely biological degradation, incineration, ozonation 9 in the presence of UV radiation, and electrochemical oxidation; 10 and recovery methods, including liquid-liquid extraction, 11 adsorption 12 and electroadsorption on activated carbon, 13 ion exchange resins, 14 and membrane processes. 15,16 The latter techniques (membrane processes) such as reverse osmosis (RO), nanofiltration (NF), and ultrafiltration (UF), are considered as methods with positive environmental impact, without phase change and with little energy consumption.…”

Ozonation of return activated sludge for disintegration and solubilisation with synthesized titanium oxide as catalyst

“…The catalyst provides more active sites on the surface for the molecular ozone to adsorb and decompose into OH•. Such metal oxide has been used in ozonation process like TiO 2 [11], MnO2 [12] and ZnO [13]. Of all, TiO2 has the advantages of higher stability, lower production cost [14] and harmless to living issue [15].…”