Preparation Of Zinc Oxide Nanomaterials With Controlable Morphology And Study On The Performance Of Ultrasonic Synergistic Catalytic Dedgeradation Of Dye Wastewater

With the rapid industry development,a large amount of industrial wastewater has been produced.Dye wastewater plays an important role in the composition of industrial wastewater,which has the characteristics of huge volume,complex composition,toxic effect and deep color.If the wastewater is discharged directly into the natural water,it will damage the ecological environment of our country,which makes the treatment of dye wastewater become gobal focus.At present,there are various degradation methods of dye wastewater have been studied and applied,which can be divided into physical methods,chemical methods and biological methods.However,these methods also have some defects,such as the complexity operation,high cost and secondary pollution during the process of treatment.Therefore,it is urgent to find a convenient,low-cost and non-secondsry pollution wastewater treatment method.Because of the advanced oxidation technique can realize the mineralization and the decomposition of organic matter,widely reported in wastewater treatment in recent years,its mechanism is produced under certain conditions for the oxidation of organic molecules into smaller molecules of hydroxyl free radicals,the reports of the advanced oxidation technology are mainly induced by optical excitation output of light catalysis,ultrasonic ultrasonic catalysis and electric driven electric catalytic,etc.Ultrasonic catalysis technology uses ultrasonic cavitation effect to produce hydroxyl radicals with strong oxidation to achieve the decomposition of dye molecules when ultrasonic wave propagates in the solution.However,ultrasonic catalytic technology can only achieve better degradation effect when using high-power instruments,but the transducer is very easy to damage at high power.In order to reduce the cost and maintain a good degradation efficiency,this paper studied the synergistic catalysis of nano-sized zinc oxide and ultrasound.The degradation effect of dye wastewater simulated with rhodamine B was analyzed by ultraviolet absorption spectrum.The main research contents are as follows:Nanometer ZnO with different morphologies were prepared by hydrothermal method.The results showed that starfish,spherical and flower-shaped zinc oxides were successfully prepared by adjusting the amount of alcohol,and the prepared zinc oxides had the characteristics of relatively narrow particle distribution,high purity and crystal complete.The synergistic catalytic degradation of rhodamine B by nano-ZnO and ultrasonic was carried out,and the degradation effect was compared with that by ultrasonic and nano-ZnO alone.At the same time,the synergistic catalysis of zinc oxide and ultrasound was investigated.The experimental results showed that hydroxyl radical and superoxide radical played a leading role in the reaction.The influence of zinc oxide morphologies on ultrasonic collaborative experiment was studied.In addition,the effects of ultrasonic power,frequency,temperature,dosage of zinc oxide and p H values on the synergistic catalytic performance were also explored.The experimental results showed that the degradation rate of rhodamine B increased with the increase of ultrasonic power,the experimental conditions are as follows :ultrasonic frequency f=36.52 KHz,ultrasonic power P=20W,temperature T=36.3?,PH=7.In addition,the amount of nanometer ZnO has a great effect on the synergistic catalytic degradation of dye wastewater,and the higher degradation effect is achieved when the concentration of ZnO is 1 g/L.The increase of reaction temperature can inhibit the degradation of rhodamine B.In order to study the reuse stability of the synergistic catalysis of zinc oxide and ultrasound,the reproducibility experiment was carried out after the recovery of zinc oxide,centrifugation and drying.Due to the loss of zinc oxide in the process of recovery,under the same experimental conditions,the degradation effect of the third repeated experiment under the same experimental time was only 46.88%.Therefore,supporting zinc oxide on ferromagnetic material Fe3O4,the results show that the supporting zinc oxide has a good and stable synergistic catalytic performance.