Study On Degradation Of Phenolic Wastewater With O₃ And H₂O₂ Intensified By A High Gravity Method

Phenolic compounds are an important species of industrial raw materials. A large amount of phenolic wastewater is mainly from the production process of industries such as plastics, resins, dyes, pharmaceuticals, pesticides, disinfectants and paint, etc. If untreated, the phenolic wastewater will pollute the environment and harm the health of human beings, animals and plants.This study involved two parts:in the first part, different conditions on the degradation effect of phenol using O3 as the oxidizer were explored in a beaker; in the second part, by referring to the beaker experiments, a rotating packed bed (RPB) was employed as the reactor to study the degradation effect of phenol using O3 and H2O2 as the oxidizers, respectively and simultaneously.The beaker experimental results indicated that the removal efficiency of phenol improved with the increase of reaction time, stirring intensity, ozone flow rate and temperature under the operating conditions. The removal efficiency of phenol reached the maximum at the pH of 9-10.The RPB experimental results indicated that the removal efficiency of phenol using H2O2 alone was unobvious, which suggests that although H2O2 is a strong oxidizer, it is necessary to combine H2O2 with other oxidizers to degrade phenol effectively.The removal efficiency of phenol improved with the increase of the rotating speed, temperature and pH whether O3 was used alone or O3/H2O2 used simultaneously; the removal rate of phenol decreased with the increase of flow rate and concentration of phenol; the removal percentage of phenol increased first and decreased subsequently with the increase of O3 flow rate and H2O2 concentration. Under the operating conditions, the optimal rotating speed, O3 flow rate and H2O2 concentration for treating 100 mg-L-1 phenol solution were 1200 r·min-1,2.5 L·min-1 and 0.02%, respectively.