Preparation Of Composite Heterogeneous Catalyst And The Performance For Advanced Treatment Of Printing And Dyeing Wastewater

Heterogeneous Fenton technology has significant effect on the application of industrial wastewater treatment,especially toxic,harmful and non-biodegradable wastewater.However,it has not been widely applied to practical projects due to the low pH application range,difficulty of catalyst recovery and high cost of running.This paper studies heterogeneous Fenton oxidation technology in the advanced treatment of printing and dyeing wastewater,reports the preparation of powder catalyst and particle catalyst which the former is suitable for the intermittent treatment of small amount of waste water,while the latter is suitable for continuous industrial wastewater treatment with larger water treatment capacity.The two catalysts were characterized and applied to the advanced treatment of printing and dyeing wastewater.The influence of various factors on the treatment effect of wastewater is provided for the practical application of the catalysts.(1)The COD and chroma degradation efficiency of printing and dyeing wastewater can be greatly improved by the copper-manganese oxide catalysts supported on acid modified attapulgite(ATP)and activated carbon.The results showed that the COD and color reached the best removal efficiency which were 92.5%and 90%,respectively,when the temperature was 25?,the amount of H2O2,1.5 times of the theoretical amount,pH of 5,and catalyst dosage of 15 g/L,reaction time of 90min.The copper and manganese oxides were dispersed on the surface of the catalysts in the form of nano particles and the active components were CuO and Mn02.(2)The catalyst was made into particles and the preparation process is explored.The best preparation conditions for the catalyst are the ratio of ATP and activated carbon of 2:1,the molar ratio of copper and manganese ions of 1:2,total mass of metal ions accounts for the total mass of the carrier of 7%,the calcination temperature of 600? and the calcination time of 3 h.When the reaction time is 120 min,the removal rate of the reactive brilliant blue X-BR solution by the catalyst is 83.2%.The XRD analysis of the catalyst shows that the active components is MnO2,the copper oxide is surported in the pores and surfaces of the catalyst in an amorphous state.(3)25?,Composite particle catalyst has high catalytic activity for printing and dyeing wastewater treatment at pH 3-6.The catalyst on the actual treatment of printing and dyeing wastewater was investigated under the condition of pH 6.The results showed that the COD and color reached the best removal efficiency which were 80%and 65%,respectively,when the amount of H2O2,1.5 mL/L,and catalyst dosage of 150 g/L,reaction time of 90 min.Leaching experiment shows that the maximum dissolution concentration of manganese of the catalyst is 1.73 mg/L,the maximum dissolution concentration of copper is 1.73 mg/L at pH 6.Under this condition,the dissolution rate of metal ions is relatively low,and secondary pollution of water treatment is less.