Experimental Study On Treatment Of Phenol Wastewater By Ultrasonic Enhanced Activated Carbon/fenton Process

The Fenton method is usually used to solve the problem of refractory wastewater.The treatment effect of this method is good,but there are still a lot of problems.For example,excessive chemical dosage and narrow p H range.According to the characteristics of the traditional Fenton method,it is important to strengthen and improve it in recent years.Phenol wastewater is the research object of this experiment.This topic discusses the effect and influencing conditions of ultrasonic-enhanced activated carbon/Fenton method for the treatment of phenol wastewater.Its significance is to make the Fenton method widely used in the field of refractory organic wastewater treatment.The experiment used simulated phenol wastewater.In the laboratory,the effect of ultrasonic-enhanced activated carbon/Fenton method for degrading phenol wastewater was studied through small experiments.The experiment determined the optimum process parameters by three methods.They are,in order,single factor experiment,orthogonal experiment,and response surface method.The first part of the research content is the Fenton method.Then the effect of activated carbon/Fenton method to treat phenol wastewater was studied.Simultaneously study the influencing factors and process conditions optimization of response surface method.The last part of the research content is the enhancement of the effect of ultrasonic on the treatment of phenol wastewater by activated carbon/Fenton method.The following four influencing factors have a great influence on the degradation of phenol wastewater by Fenton method.They are reaction time,p H value,Fe SO₄·7H₂O dosage and H₂O₂ dosage,respectively.Orthogonal test results show that the order of the influence of each factor is p H value>Fe SO₄·7H₂O dosage>H₂O₂ dosage>reaction time.The optimal reaction conditions were p H 3,30%H₂O₂ of 7.2m L/L and Fe SO₄·7H₂O of 1000mg/L,and the time was set to 90min.Under the optimal reaction conditions,the phenol wastewater with a phenol concentration of 302 mg/L and a COD concentration of 719 mg/L was degraded.The removal rates at this time were 84.37%and 76.65%respectively.The effect of the modified activated carbon/Fenton method for degrading phenol wastewater was better than that of the traditional Fenton method.The response surface test results show that the influence of each factor on the reaction is:p H value>reaction time>modified activated carbon dosage.The optimum reaction conditions were p H 3,7.2m L/L of 30%H₂O₂ and 1000 mg/L of Fe SO₄·7H₂O were used,and 7.4g/L of modified activated carbon was used,and the time was set to 60 min.It was used to degrade phenol wastewater with a COD concentration of 718mg/L,and the removal rate was 82.22%.After completing the response surface test,the following conclusions are drawn.The p H value has the most significant effect on the reaction.The use of modified activated carbon extends the proper p H range to 2-5.Ultrasound can enhance the effect of activated carbon/Fenton method to degrade phenol wastewater.The test conditions were p H 3,adding 7.2m L/L of 30%H₂O₂and 1000mg/L Fe SO₄ 7H₂O,using 7.4g/L modified activated carbon.The temperature of the ultrasonic device is 25℃,the frequency is 40KHz,the power is 120W,and the reaction is 60min.It is used to degrade phenol wastewater with a COD concentration of 713mg/L.The removal rate of COD reached 89.79%.Compared with the activated carbon/Fenton method,the removal rate increased by a little more than 7%.On the premise of the same removal rate,the strengthening effect of ultrasonic can reduce the use of chemicals.The ultrasonic-enhanced activated carbon/Fenton method has an ideal degradation effect on phenol wastewater.On the one hand,the ability of traditional Fenton method to remove organic pollutants is improved.It broadens the range of use of p H.On the other hand,it can improve the degradation rate and save chemicals.The research of ultrasonic strengthening activated carbon/Fenton method is of great significance.The most important thing is to promote the widespread use of the Fenton method in the field of refractory wastewater treatment.