Study On Structure And Performance Of Rare Earth Oxide Hollow Spheres Prepared By Hydrothermal Method

The special wettability of object surface is an important part of modern bionics.Superhydrophobic surface is a special case of object surface wettability.In recent years,the use of superhydrophobic materials to separate oily wastewater has attracted more and more attention.As a cheap and easy-to-obtain alloy material,stainless steel mesh has very good stability,toughness and machinability.In this paper,superhydrophobic surface was prepared on stainless steel mesh by three different methods.The main research contents are as follows:Nano-sized silica particles were prepared by hydrolysis of tetraethyl silicate under alkaline conditions.Dimethyldiethoxysilane was used for hydrophobic modification.The nano-scale rough structure was constructed on the surface of 100 mesh stainless steel mesh by direct immersion method.The super-hydrophobic stainless steel mesh with water contact angle of 155°was finally prepared.The effects of soaking times and aging time on the surface wettability of the samples were studied,and the formation mechanism of silica was discussed.The surface morphology of stainless steel was analyzed by scanning electron microscope,and the surface composition of stainless steel mesh was analyzed by Fourier transform infrared spectroscopy.Super hydrophobic surfaces were prepared on stainless steel by chemical etching and self-assembly.First,the surface of stainless steel mesh was etched by hydrochloric acid,then iron stearate was formed by the combination of stearic acid and Fe²⁺produced by reaction,and then superhydrophobic material with contact angle of 152.2°was prepared by soaking the stainless steel mesh in stearic acid.The influence of etching solution concentration and reaction time on water contact angle of the sample surface was analyzed.The reaction principle was analyzed.Finally,the stability of superhydrophobic performance of the prepared stainless steel mesh was investigated.Titanium dioxide sol was prepared by hydrolysis of butyl titanate in acidic condition.Titanium dioxide film was prepared by coating the sol on the surface of stainless steel mesh as adhesive.Titanium dioxide with micro-nano composite rough structure was prepared on stainless steel mesh by hydrothermal deposition using butyl titanate as titanium source.Superhydrophobic surface with water contact angle of152.9°was prepared on the surface of stainless steel mesh by modifying the surface with n-octadecyl mercaptan.The effect of titanium dioxide sol pretreatment on the stability of superhydrophobic stainless steel mesh was analyzed.The corrosion resistance of superhydrophobic stainless steel mesh was studied.Oil-water separation of naphthenic oil,kerosene,peanut oil and gasoline was carried out by a self-made oil-water separation device.The effect of separation times on the separation efficiency was studied.Comparing the theoretical value with the actual value,it is found that the actual value is slightly higher than the theoretical value.