Preparation Of Modified Polyurethane Foam Composites And Application In Adsorption Of Dye And Oil/water Separation

Along with the social industry,transportation,high-speed development of offshore oil production and modern chemical industry,marine oil spill and organic chemical reagent leakage accident,dye waste water emissions caused serious damage to the local water environment.At present,the most basic way to deal with the water pollution is to absorb the pollutants in the water with the absorbing material,so as to achieve the purpose of control.Polyurethane foam is a typical porous material,which combines polymer material properties,flexible material damping function,porous material with high porosity,large surface area,the pore structure characteristics of the exchange,is a kind of good adsorption material.So it is very important to study the foam material in water pollution treatment.The purpose of this study is to approach the development of efficient,cheap and environment friendly to the preparation of efficient dye adsorption,oil-water separation,and excellent oil recovery efficiency polyurethane foam materials.The main research contents and results are as follows:?1?The polyurethane foam composites modified with coal were prepared by one step foaming.The ratio of raw materials of polyurethane foam composites modified with coal was optimized,and a new coal-based polyurethane foam adsorbent was obtained.The C/PUF was applied to remove brilliant green?BG?from aqueous.The effects on coal content,adsorbent dosage and BG dye solution temperature adsorption efficiency by a group of adsorption experiments were evaluated.Under the optimum conditions,the removal efficiency of the dye can reach up to 99.4%.The isothermal adsorption results show that the Langmuir isothermal model can simulate the adsorption behavior of C/PUF on BG,and the maximum adsorption capacity of BG is134.952 mg/g.The adsorption kinetics of system was investigated and the result showed that the adsorption of BG onto C/PUF material followed pseudo-second-order kinetic model.The adsorbent shows a remarkable regeneration capability?no obvious change in absorption capacity?,which makes them an ideal candidate BG removed from the solution.This present study shows an economic way to treat BG using the?2?polyurethane foam materials modified with a low-cost coal by one step foaming technology.?2?The CNT was oxidized by nitric acid?HNO3?and sulfuric acid?H2SO4?to obtain CNT-OH.CNT-OH and silane coupling agent?KH 570?as modifying agent,the novel absorbent of carbon nanotubes?CNT?based on polyurethane?PU?foams,which was prepared by one-step method.Polyurethane foam material was observed by scanning electron microscopy?SEM?before and after the modification of the bubble pore structure and pore size distribution.The thermal stability was investigated,and the hydrophobicity of composite materials was evaluated by the water contact angle?WCA?.The CNT content was investigated to measure the oil absorption capacity of the CNT/PUF composites.The results show that addition of the modified CNT significantly improves the heat resistance and oil absorption capacity?3?A common and feasible approach to hydrophobic aluminium oxide?Al₂O₃?reinforced polyurethane foam was investigated.The hydrophobicity,oil-absorption capacity,and reusability of the PUF modified with Al₂O₃?Al₂O₃/PUF?were tested.The results show that water contact angles of the modified PUF across the surfaces were found to exceed 140°,indicating that the modified PUF possessed good hydrophobicity.The oil can be easily absorbed within a few seconds after contact with the modified PUF.The absorption capacity of modified PUF was 37 g/g.The modified PUF was found to be reusable up to10 cycles while maintaining its high absorption capacity.?4?The hydrothermal method was employed to synthesize MnO₂ nanowires.MnO₂ nanowires/polyurethane?PU?foam composites,a facile,inexpensive to fabricate,effective and recyclable oil-absorbent,was prepared with MnO₂ nanowires as modification agent and PU sponge as a porous substrate through the foaming technology.MnO₂ / polyurethane?PU?foam composites were prepared by foaming technology using MnO 2 nanowires synthesized by hydrothermal method as the modifier and PU sponge as the porous substrate.In order to enhance the hydrophobic and oleophilic properties,the surfaces of MnO₂ nanowires are chemically modified using silane coupling agent?KH 570?.The present MnO₂ nanowires/PU foam composites not only effectively separate oils from water,but also possess a very high absorption capacity for the removal of organic solvents from water up to 40.15 times its own weight.More importantly,the obtained MnO₂ nanowires/PU foam composites is demonstrated to have excellent oil recoverability and absorbent regenerability to satisfy various practical oily wastewater and organic solvent separation requirements.?5?Mg–Al porous fiber?Mg–Al PF?/polyurethane?PU?foam composites was prepared by a novel strategy,which combining the biotemplate method and foaming technology.The application in the absorption of oils and organic solvents was discussed.The Mg–Al PF composites with a hierarchical porous structure are fabricated based on nanoplatelets on the surfaces of microscale inorganic fibers.The PU foam composites with excellent oil swelling properties are synthesized by addition of Mg–Al PF composites to PU foams.The surfaces of Mg–Al PF composites are chemically modified using silane coupling agent?KH 570?,and the water contact angle was 146.6°,the Mg–Al PF exhibited the good hydrophobic property.Owing to their unique pore structures,superhydrophobic and swelling properties,the foam composites can remove oils and organic solvents from water with high selectivity and absorption capacity,and can absorb not only floating oil but also heavy organic solvents underwater.In general,the absorption capacities of the PU foam composites for oils and organic solvents are 5.06–44.81 times their own weight.The PU foam composites still maintain relatively consistent absorption properties for oil and organic solvent absorption after 10 cycles.These outstanding properties potentially make the as-prepared PU foam composites promising candidates for practical oil absorption and oil/water separation.