Treatment of industrial wastewater containing recalcitrant pollutants for reusing is an important issue. Nowadays, advanced oxidation processes (AOP) are used to remove non-biodegradable toxic organic compounds or convert them into biodegradable materials. These processes consist of two oxidation steps which include formation of strong oxidants and their reaction to water organic compounds. Considering that furfural and hydroxymethylfurfural (HMF) are two important pollutants of industrial wastewaters, especially in oil and food industries, their removal is necessary. The aim of this study was to investigate the effect of microwave (MW) irradiation/H 2 O 2 approach on degradation of the this compounds in aqueous environment. At first, the effect of MW irradiation and adding H 2 O 2 on removal of the compounds were investigated individually. Then, the effect of irradiation time, MW intensity, pH as well as concentration of H 2 O 2 and contaminants on removal efficiency were evaluated. In order to achieve this, water samples containing 100 mg L -1 furfural and HMF were treated under various MW irradiation times (10, 20, 30, 40, 50, 60, 70 min) and removal efficiency and the efficient time were evaluated. Then, the effect of MW intensity (180, 540, 900 watt) on removal efficiency was studied. Besides, the effect of pH (3, 4, 5, 6, 7, 8, 9), H 2 O 2 concentration (300, 600, 900, 1200, 1500 mg L -1 ) and concentration of furfural and HMF (5, 10, 15, 25, 50, 100, 150, 200 mg L -1 ) were individually studied. Finally, the effect of MW irradiation/H 2 O 2 on furfural and HMF removal were investigated in a wastewater sample of Tehran Refinery considering the optimized conditions obtained from previous experiments. The result showed that the removal of furfural and HMF were maximum after 40 and 50 min of irradiation, respectively and the highest degradation of compounds was in MW intensity of 900 watt, pH=3 and H 2 O 2 concentration of 900 mg L -1 . The maximum amount of furfural and HMF degradation was in the samples containing 100 mg L -1 of each compound. The results of this study confirmed that the efficiency of the method in removal of furfural in the wastewater was more than 97%. Overall, it can be concluded that MW/H 2 O 2 AOP is a suitable method for removal of furfural and HMF from water solutions. However, this method should be evaluated economically before using in field conditions. Keywords : Advanced oxidation processes, Microwave, Furfural, Hydroxymethylfurfural, Water treatment
