Preparation And Oil-water Separation Of Hydrophobic Oleophilic Polyurethane Sponge

In recent years,with the rapid development of economy,oil production demand and transportation are increasing day by day.Oil spill accidents occur frequently due to drilling platform exploitation,tanker transportation,storage,war and natural disasters,which not only wastes a lot of crude oil resources,but also poses a great threat to the Marine ecological environment.In addition to oil spill accidents,the leakage and discharge of a large number of oil-containing wastewater and insoluble organic solvents in manufacturing industry also threaten the living environment of human beings.At present,adsorption method has attracted much attention because of its advantages of simple operation,low cost and flexible design.Because it can collect and completely remove oil stains on the water surface,no adverse effects on the surrounding environment after treatment.Inspired by lotus leaves,desert beetles and other creatures,researchers have found that their super-wetting properties promise a solution to oily wastewater pollution.In recent years,polyurethane,melamine and other sponge adsorbents have attracted attention in oil-water separation treatment due to their advantages of low cost,good elasticity,three-dimensional structure and convenient design.The hydrophilic sponge surface can be changed into hydrophobic sponge surface by material modification.Sponge adsorbent becomes a new kind of oil absorbing material because of its excellent properties.In this paper,polyurethane sponge materials were prepared by three modification methods respectively.The research contents are as follows:1.A novel magnetically driven hydrophobic polyurethane sponge was synthesized by simple impregnation method.Isodecanol with long carbon chain was grafted to the surface of sponge by substitution reaction and condensation reaction,and Fe3O4 nanoparticles were adhered to the sponge,giving it magnetism and making it easy to collect.It was characterized by Fourier transform infrared spectroscopy(FT-IR),X-ray diffraction(XRD),scanning electron microscopy(SEM)and energy dispersion spectrometer(EDS).The maximum adsorption capacity for various oils/organic solvents is 24-50 times its own weight.After ten cycles of use,it shows good reusability.In addition,due to its high porosity,hydrophobicity and lipophilic characteristics,it can selectively absorb oil in a wide range of water and continuously separate oil-water mixtures.2.Using commercial polyurethane sponge as substrate,the modified sponge was successfully prepared by substitution and esterification reaction,connecting the long carbon chain of 1-octadecanethiol to the surface of sponge skeleton.After modification,the hydrophobic Angle is 149°,after 10 absorption-extrusion cycles,it has good reusability,good oil absorption capacity of various oil/organic solvents,adsorption capacity is 20-46 times of its own weight,with high efficiency oil and water separation ability and good selectivity and adsorption performance.The results show that the modified sponge has potential application prospect in oil purification and oil removal industry.3.Superhydrophobic polyurethane sponge was prepared by soaking polyurethane sponge in ethanol solution containing tannic acid and testamine.The samples were analyzed and tested by XRD,SEM,XPS,etc.The results showed that the sponge with high porosity,elasticity and mechanical stability was modified with testamine and Fe3O4 with low surface energy.The modified sponge not only had superhydrophobic surface,water contact Angle was 156.5°,but also showed excellent oil-water adsorption separation performance and recycling ability.