Preparation Of CuFe₂O₄/Zeolite Composite Material And The Effect Study Of Catalytic Ozonation

In the current water treatment process,heterogeneous ozone-catalyzed oxidation technology has been widely concerned by scholars at home and abroad due to its outstanding catalytic activity,easy material recovery and simple process flow.In particular,the research and development of new and efficient catalysts has become a hot topic.The purpose of this paper is to synthesize CuFe₂O₄/zeolite composite by simple,quick and easy operation,to investigate its catalytic ozone-oxidizing effect on the degradation of atrazine in water,to explore its catalytic oxidation mechanism and the degradation path of pollutants in water.In this paper,different kinds of zeolite and loading ratio of CuFe₂O₄/zeolite composites were prepared by sol-gel method.Taking atrazine as the target pollutant,activation properties of different catalysts were explored and the optimal catalytic activity of the composite materials was obtained when the mass ratio of CuFe₂O₄ and natural zeolite was 1:1.It is characterized by scanning electron microscope?SEM?,X-ray diffraction?XRD?,X-ray photoelectron spectroscopy?XPS?,and vibrating sample magnetometer?VSM?,among other techniques.The surface morphology,structure composition and magnetic saturation strength of the catalyst were determined.Secondly,the effects of catalyst dosage,ozone dosage,initial pollutant concentration,system temperature,reaction p H,inorganic anion and natural humic acid on the degradation efficiency of atrazine in the catalytic ozonation system were studied.Meanwhile,based on the reaction kinetics theory,the catalytic reaction process was fitted and analyzed,and the optimal combination of experimental conditions with degradation efficiency and economic benefits was selected: the system temperature is 20?,the solution p H=7.0,atrazine initial concentration of 2 microns,activator dosing quantity is 0.2 g/L,ozone dosage is 3.5 mg/L.It was found that there was a positive correlation between the amount of ozone and the removal rate of atrazine.The p H of the solution is acidic or alkaline and the increase of pollutant concentration will make the degradation effect of atrazine worse.The amount and temperature of the catalyst in a certain range were synergistically promoted with the degradation efficiency of the reaction,and were negatively correlated with the removal rate beyond a certain range.With the increase of Cl^-,HCO₃^-,NO₃^-and SO42-ion concentrations,the degradation efficiency of atrazine decreased to some extent.When the concentration of natural humic acid is low,the removal of atrazine can be inhibited,and the catalytic performance can be improved when the concentration of natural humic acid is high.It was inferred that ·OH was the main active species in the catalytic ozonoxidation reaction through the validation of competitive reaction and surface hydroxyl group.In addition,this study also used LC-MS to detect the intermediates in the atrazine reaction process,and successfully inferred the possible degradation path of atrazine,and further explored the reaction mechanism of catalytic ozonation degradation of atrazine.The study showed that the cyclic transformation between Cu²⁺/Cu³⁺,Fe²⁺/Fe³⁺ and O₂/O^2-in the system was the key to the catalyst to play a high activity.The CuFe₂O₄/zeolite composite prepared in this study has good magnetic properties,low metal dissolution,high recycling efficiency,and stable physical and chemical properties and structure before and after use.