Preparation Of High-Performance Oil-Water Separation Materials And Performance Research

In recent years, oil spill accidents happened frequently, killing tens of thousands of sea creatures every year, causing irreparable damage to the ecosystem. The use of oil-water separation material was found to be one of the most economic and efficient method in the treatment of oily wastewater.In this thesis, cheap stainless steel mesh was used as the base, while LDPE, SiC, PTFE, stearic acid were used as the main modification agents. The hydrophobic/oleophilic stainless steel mesh was prepared by soaking method and etching method. The surface micro structure and chemical composition of the modified stainless steel mesh were characterized by means of scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), infrared spectroscopy (FTIR) and energy dispersive spectrometer (EDS). The hydrophobic property of the modified stainless steel mesh was characterized by the OCA20 contact angle tester. The oil-water separation efficiency, oil-water separation rate, corrosion resistance and reusable performance of the modified stainless steel mesh were investigated. The results are as follows:1. LDPE modified stainless steel mesh was prepared by soaking method with stainless steel mesh as raw materials and low density polyethylene as modifying agent. The average contact angle of water droplets can reach 125° when the concentration of low density polyethylene is 15.12 g/L. By adding silicon SiC or PTFE particles into the low density polyethylene solution, the average contact angle of water droplets can reach 139° and 142°, respectively.2. Stainless steel mesh was etched with FeCl3 as etching liquid. The etched stainless steel mesh has rough surface of micro-nanometer combined structure. Then the etched stainless steel mesh was modified with ODT by soaking method. When the mass fraction of ODT is 0.1%, the average contact angle of water droplets can reach 150° , indicating a super-hydrophobic property. Experiments show that the ODT modified stainless steel mesh has great corrosion resistance and reusable performance. The ODT modified stainless steel mesh can be used as key material to prepare oil-water separation device with shows an oil-water separation efficiency as high as 98.5% and an oil/water separation rate up to 1900L·min-1·m-2. The ODT modified stainless steel mesh can meet the requirements of offshore oil spill recovery operations and has wide application prospects.3. Hydrophobic stainless steel mesh was prepared by soaking method with stearic acid as modifier. When the mass fraction of stearic acid is 0.1%, the average contact angle of water droplets can reach 145°. The stearic acid modified stainless steel mesh can be processed into a "boat" model. The experiments show that the oil-water separation efficiency of "boat" model is as high as 98.5%.