Construction And Application Of Oil-water Separation Material Based On Melamine Sponge

In recent years,oil spills and organic solvents have caused serious damage to water resources.It not only affects the ecological environment,but also threatens the survival and development of human society.Physical adsorption is an efficient method to treat oily wastewater.However,the current adsorption materials still have problems such as low adsorption capacity,poor selectivity and recycling,high preparation cost,and ineffective separation of oil-water emulsion.Therefore,it is very important to prepare a super hydrophobic,high efficient and environment-friendliness oil-absorbing material.In this paper,three-dimensional porous commercial melamine sponge(MS)was used as the base material to prepare its hydrophobic modification in different ways,and its application in oil-water separation was explored.Firstly,we explored the effect of temperature to modification the MS.By comparing with samples at different temperatures,the superhydrophobic sample with better performance was selected and tested for its performance and structure.Through tests of Scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectrometer(XPS),Mass spectrum(MS),it was analyzed that the hydrophobic reason was mainly caused by removing hydrophilic groups on the surface of MS at temperature,thereby reducing the decrease surface energy of MS.After that,the prepared superhydrophobic MS with density of only 5 mg·cm-3,ultra-high adsorption capacity(133-284 g· g-1)and excellent cycle performance(50 cycles)was applied in the selective of different types of oil-water separation to realize effective treatment of waste water.In order to adapt the general requirements of sponge modification,MS was modified through increase surface roughness and reduce surface energy.Activated carbon(AC)was selected to increase the surface roughness of the MS,and PTFE solution reduced the surface energy of the MS.The optimal ratio of AC and PTFE was explored,and the superhydrophobic AC/PTFE-MS samples with good performance were prepared.The composition,structure and properties of the samples were tested.Through the surface wettability,compression cycle,oil-water separation experiments,the prepared superhydrophobic AC/PTFE-MS samples can maintain good hydrophobic after complete 50 cycles compression experiments,selective adsorb oil float on the water and heavy oil under water,achieve efficient separation of oil-water mixture,especially emulsion to treat wastewater and repair the environment.Furthermore,it can be applied to fabricate other similar hydrophobic materials through increase the surface roughness and decrease the surface energy.Finally,in order to further optimize the defect of AC and obtain the different carbon materials can also achieve superhydrophobic by combining with PTFE,graphene was selected as carbon material to increase the surface roughness and combine with PTFE to modify MS.GPMS with superhydrophobic and superhydrophilic were successfully prepared.The microscopic morphology and structure characteristics of GPMS were characterized and tested.The experimental results show that the prepared superhydrophobic GPMS has excellent recycle performance,and can efficiently and selectively separate oil-water mixture and emulsion,so as to realize effective recovery and reuse of oily sewage.This superhydrophobic material has a great application prospect in the treatment of water environmental pollution.More importantly,it modifies the three-dimensional porous sponge material by combining the carbon material and low surface energy material,providing a new design idea for the preparation of superhydrophobic material.