Preparation Of Superhydrophobic Copper Mesh And Its Oil-Water Separation Performance

Oil-water separation is critical to the handling of oily wastewater or oil spills.Oily wastewater not only causes serious water pollution,but also threatens human health and all living things in the ecosystem.In order to meet this challenge,different manufacturing methods have been applied to impart special wetting properties to porous materials based on the principle of bionics,which provides an effective solution for oil-water separation.Although conventional oily wastewater treatment technologies,such as insitu combustion,centrifugal separation,filtration and neutralization,can effectively solve the pollution problem,they usually have low separation efficiency,complicated steps,long time,high cost and even secondary pollution,and can not realize large-scale industrial production.More seriously,incomplete separation often results in oil remaining in the water or residual water in the oil,which still poses a potential risk to the organism.Therefore,this paper aims to produce a superhydrophobic copper mesh with high efficiency,rapidity,selectivity and reusability for oil-water separation based on reasonable material design.In this paper,the copper mesh is used as the base,and the copper mesh is treated by etching method and hydrothermal method.An uneven copper oxide and a hexagonal columnar zinc oxide structure are formed on the surface of the copper mesh,after modification,a superhydrophobic copper mesh with high efficiency of oil-water separation is successfully prepared.Scanning electron microscopy(SEM),X-ray diffractometry(XRD)and Fourier transform infrared spectroscopy(FT-IR)is used to study the surface structure,composition and morphology of the superhydrophobic copper mesh.Wetting factors,reusability and oil-water separation ability are tested.The main research work and results are as follows:1.By controlling the parameters of Fe Cl3 solution concentration,etching reaction time and copper mesh number,the brass mesh is etched by Fe Cl3 solution and calcined at high temperature,then modified by stearic acid ethanol solution to prepare super hydrophobic super-lipophilic copper mesh.The experimental data show that the superhydrophobic copper mesh prepared by this method can reach the contact angleof water with 152o,the oil droplets can penetrate the copper mesh within 10 ms,and it has high oil-water separation ability for different types of oil-water mixtures,and the separation efficiency is over 85%.and can be reused more than 30 times.The oil content in the separated oil-water mixture is tested by an infrared oil detector,and the oil content in the water is determined to be 55.38 mg/L.In addition,after soaking for20 days with Na Cl solution and p H = 5,p H = 9 solution,the oil-water separation efficiency is still above 80%,and has good corrosion resistance.2.Using a hydrothermal method in the experiment,a layer of nanometer zinc oxide is grown on the surface of the brass mesh and modified by cetyltrimethoxysilane to prepare a superhydrophobic superlipophilic copper mesh.The results show that the contact angle of superhydrophobic copper mesh prepared by this method can reach 152o,and the kerosene droplets can completely infiltrate the copper mesh within 20 ms,which can effectively separate different oil-water mixtures such as kerosene,petroleum ether and n-hexane.Repeated separation for 100 times,the separation efficiency is still as high as 90%,and the oil content in the water after separation is 33.23 mg/L,which realizes the preliminary purification of oily wastewater.