Micro Electrolysis-Fenton Combined Pretreatment For O-Aminophenol Wastewater

The process of o-aminophenol’s production generates wastewater which contains o-aminophenol. It would produce great harm to human, water, soil, and animals while entering to the environment. Therefore, we must pay more attention to the treatment of o-aminophenol wastewater. Due to o-aminophenol’s huge toxicity and bad biodegradability, it can not be directly treated with biochemical methods and needs the pretreatment firstly. Given the simple operation, rapid response and without secondary pollution of micro electrolysis-Fenton’s reaction system, it is employed as the pretreatment in this paper to explore its treatment effect on o-aminophenol wastewater and optimize the process parameters, so as to provide reference to the treatment and engineering design of o-aminophenol wastewater. The paper’s main results are as following:1) Micro electrolysis redox and electrocoagulation can be used in the treatment of o-aminophenol wastewater. It could reduce the COD, ammonia and aniline in the water. Through the experimental analysis, we can draw the optimum pH, iron-carbon weight ratio, duration and effluent pH were 3,7:1,90 min and 9.5 respectively. After its treatment, COD removal efficiency was about 55%, ammonia removal efficiency was about 55% and aniline removal rate was about 54%.2) Micro electrolysis-Fenton combined technology for o-aminophenol wastewater was with higher treatment effect. The effluent after micro electrolysis would then be added with hydrogen peroxide and without no need to be neutralized directly. Fenton reaction required that reaction pH was about 4, water pH was about 9.5, reaction residence time was about 90 min. Compared to micro electrolysis and Fenton separately, micro electrolysis-Fenton combined technology improved the treatment effect and reduced the secondary contamination, due to the introduction of iron etc.3) COD removal rate, ammonia removal efficiency and aniline removal rate for micro electrolysis-Fenton were 74%,75% and 83% respectively, the combined technology enhanced the biodegradability of the effluent.Taken together, micro-electrolysis -Fenton combined technology is feasible for the pretreatment of o-aminophenol wastewater.