Abstract:

Traditional technology of wet oxidation was often carried out under the situation of high temperature and pressure, which results in low efficiency of the reaction, serious wear of the reactor and harsh reaction conditions. And the degradation rate and efficiency was often under at a lower level. The objective of this study was to elucidate the mechanism degrading wastewater by using MW-CWPO, in which the production of hydroxyl radicals can be promoted, and hence improves the degradation of pollutants under relatively gentle conditions. In this research, p-nitro phenol (100 mg/L) was used as target pollutant, and carbon nanotubes and hydrogen peroxides were used as catalysts and auxiliary oxidant. It is investigated that the high power, high pressure, and high concentration of catalyst and oxidant can effectively improve the degradation efficiency of organic wastewater. Besides, it was found that MW radiation can promote hot spot (exceed 1000℃) formation on the surface of catalysts, which can enhance hydroxyl generation by the decomposition of oxidizers and dissolved oxygen at the condition of high temperature. Additionally, the catalysts after reaction were scanned by electron microscope and find that the surface of the carbon nanotube used in the experiment had no apparent modification, so that it can be reused for a long time. Since factors such as pressure can enhance the degradation rate of organic wastewater, they can be controllably modified to accelerate chemical reactions or improve degradation rate of actual chemical industry wastewater.