Study on Activated Carbon Supported Cerium Catalytic Ozone Oxidation of Chloramphenicol
|Course||Architecture and Civil Engineering|
|Keywords||catalytic ozonation activated carbon supported cerium CAP(chloramphenicol) degradation|
In recent years, antibiotics pollution problems and its potential hazards have attracted many domestic or foreign researchers. Especially, current conventional sewage treatment processes could not remove antibiotics from water and therefore,in order to protecte the water environment, it is necessary to develop an effective technology to deal with antibiotics in water.In the paper, activated carbon supported cerium is selected as catalyst in catalytic ozonation process to degrade chloramphenicol(CAP), one kind of typical antibiotics in the water.Removal, preparation methods, reaction parameters and related mechanisms are discussed in details, and some conclutions are as follows.Firstly, it is found that AC-Ce Catalytic ozone oxidation process performance high efficiency in degradation of chloramphenicol. It can promote the removal and reaction rate compared with that achieved by ozonation alone.During the reaction CAP removal was up to more than 90% after 5 minutes while only 58% by ozone alone.Secondly, different preparation conditions such as cerium load, ultrasonic time, baking temperature may change the activity of catalysts. Results show that the catalytic activity reached optimal when 0.5% cerium was doped onto AC supporter, then ultrasound for 60 minutes, and rosted in nitrogen protection oven at 500℃Thirdly, operation parameters, including initial concentration of chloramphenicol, catalyst amount, ozone dosage, temperature, pH value and times of catalysts using were investigated.The rusults indicate that AC-Ce/O3 process is suitable for treating raw water contaminated by lower concentration of CAP(not more than 5 mg/L), when ozone dosing is 100 mg/h, AC-Ce catalysts 1.0 g/L, and control reaction temperature at 30℃, pH value at 9, the degradation results could be better.Lastly, the removal efficiency of AC-Ce Catalytic ozone oxidation is better than that of catalyst adsorption and ozone oxidation, catalyst adsorption and ozone oxidation play synergy role in this reaction. The research shows that the efficiency of ozonation alone and AC-Ce Catalytic ozone oxidation process are increasing with the pH value of the solution; tert-butanol in aqueous solution could significantly affects the activity of AC-Ce catalytsts, and CAP is possibly oxidized by hydroxyl radicals in solution.