Experimental Study On Treatment Of Acid Orange Ⅱ Dye Wastewater By O₃/H₂O₂/K₂FeO₄ System

Ozone advanced oxidation with ozone oxidation as the core process has been widely used in the treatment of refractory organic wastewater due to its advantages of no secondary pollution,high efficiency and speed.However,how to improve the utilization rate of ozone and broaden the range of p H reaction has been the focus of research in recent years.The purpose of this study is to study the effect and process conditions of O₃/H₂O₂/K₂FeO₄system in treating acid orangeⅡazo dye wastewater,and to provide technical basis for the popularization and application of this method.The experiment took acid orangeⅡwastewater as the treatment object,and researched the effect and process conditions of O₃/H₂O₂/K₂FeO₄system in treating acid orangeⅡazo dye wastewater through small test.The effects of main single factors on the treatment effect of acid orange II wastewater by O₃/H₂O₂system were investigated experimentally;After the introduction of K₂FeO₄into the O₃/H₂O₂system,the dosing amount and dosing method of K₂FeO₄affected the treatment effect of the O₃/H₂O₂/K₂FeO₄system,the initial p H value and the dosing amount of ozone.The optimal process parameters were determined by response surface method,and the reaction mechanism of the system was analyzed.The experimental results of the O₃/H₂O₂system for treating acid orange II wastewater show that the p H value,the dosage of H₂O₂and the dosage of ozone have a great influence on the treatment effect.For acid orange II wastewater with a COD concentration of 340mg/L and a chroma of 550 times,when p H=10,the dosage of 30%H₂O₂is 1.5ml/L,and the dosage of ozone is 24.8mg/min,after 50min The removal rates of COD and chroma were 55.63%and93.55%,respectively.Adding K₂FeO₄reagent to O₃/H₂O₂system can not only improve the treatment effect of acid orange II wastewater,but also widen the range of initial p H value.For the O₃/H₂O₂system,when the dosage of K₂FeO₄was 30mg/L,the COD removal rate increased by 10.5%,and the initial reaction p H value was broadened to 8-10.The dosing method of K₂FeO₄has an impact on the treatment effect.The batch dosing is better than the one-time dosing,and the COD removal rate is increased by 4.83%and 6.56%.Adding K₂FeO₄reagent can improve the utilization rate of ozone.Under the condition of equivalent removal effect,the dosage of ozone is reduced from 24.8mg/min to 20mg/min,which reduces the treatment cost.The BBD response surface method in the RSM model was used to optimize the process parameters,and the optimal process parameters were obtained as follows:the p H value is 9.7,the dosage of ozone is 26.2mg/min,the dosage of K₂FeO₄is 28.7mg/L,30%The dosage of H₂O₂is 1.5ml/L.Under these conditions,acid orange II wastewater with a COD concentration of 340 mg/L and a chromaticity of 550 times was degraded for 50 minutes,and the average removal rates of COD and chromaticity were 76.49%and 97.49%.The key to the oxidative decomposition of acid orange II wastewater in the O₃/H₂O₂/K₂FeO₄system is the generation of hydroxyl radicals during the reaction.CO₃^2-and Cl-have inhibitory effect on the treatment effect of O₃/H₂O₂/K₂FeO₄system,while SO₄^2-has no effect on the treatment effect.The treatment of acid orangeⅡdye wastewater by O₃/H₂O₂/K₂FeO₄system conformed to the first-order kinetic model.The O₃/H₂O₂/K₂FeO₄system has an ideal treatment effect on acid orange II dye wastewater.The introduction and batch addition of K₂FeO₄improves the treatment effect,broadens the p H value range,and makes the operation more convenient.The method has a good application prospect in the field of refractory biodegradable organic wastewater treatment.