Study On Preparation And Properties Of Oil-separation Filter Papers And Oil-absorbing Polymer

The application amount of oil production is increasing gradually in theworldwide. Meanwhile, a bunch of crude oil and oil production leak during processof transportation, processing, mining and the like. However, leaking of crude oil,even in a small amount, will also be a strong beat to local ecosystems. The methodto avoid this damage is by using superhydrophobic material to separate oil-watersystem and oil-absorbing polymer to absorb oil pollution.Superhydrophobic material is the material with the contact angle more than150degrees and the sliding angle less than10degrees, which depends on the chemicalcomposition and the morphology of the surface. Oil-absorbing polymer is a kind oflow cross-linked polymer with a large amount of lyophilic groups. And by far, mostsuperhydrophobic material are reported been polymer and metallic oxide. It shouldbe mentioned that polymer will be swelled or dissolved in low-polarity liquid. Andmetallic oxide is toxic in water.This dissertation concentrates on developing a sort of superhydrophobic filterpapers with a large amount of silica nano-particles which are easy to change surfaceenergy and stabilize separating oily liquid by dipping-coating. I also preparedoil-absorbing polymer by free radical polymerization and ionic self-assembly toabsorb variety of liquids. Besides, I studied the relationship between surfacewettability and processing conditions, and the surfaces were applied to separateliquids differing in surface tension.1. By controlling the stirring speed and the concentration of raw materials, silicanano-particles with different diameters can be prepared by Stober method. Superhydrophobic filter papers can be prepared by silica nano-particles withdifferent diameters, different immersion methods and different modified material.After dipping the filter paper in176nm silica nano-particles for4times andmodified by n-octadecyltriethoxysilane, filter papers become superhydrophobicwhich contact angle is151.5degrees and sliding angle is12.1degrees.2. Using the superhydrophobic filter papers to separate water-n-octane system,n-octane content in water should be less than5wt%after separation. Ethyleneglycol-n-octane system should be less than60wt%n-octane content, whilen-octane content in ethylene glycol should be less than5wt%, after separation.Nevertheless, the separation ability to water-methanol system is relatively low.3. I prepared the oil-absorbing polymer by free radical polymerization andinvestigated the effects of different raw material ratio, crosslinking reagent, thelength of the alkyl chains and the polarity of liquid on the absorption. And thefact is when molar ratio of stearyl acrylate to styrene is5:5, the absorbingcapability of copolymer is the strongest. When molar concentration ofcrosslinking reagent is0.5%, the absorbing capability of copolymer is thestrongest. The longer alkyl chains is, the better absorbing ability the copolymerhas. When the polarity of liquid increases, the absorbing ability of thecopolymer increases firstly and then decreases and the highest point is on THF.The absorbing ability of copolymer to coal-oil-water system is between pure coaloil and water. This copolymer can also be used repeatedly.4. I prepared two kinds of oil-absorbing polymer by ionic self-assembly with CTABand DDAB. When the polarity of liquid increases, the absorbing ability of thepolymer increases firstly and then decreases and the highest point is on THF.The polymer with DDAB has a lower crystallization temperature and more alkylchains, so its absorbing ability is better the polymer with CTAB. And theabsorbing capability of polymer to THF will maintain steady after digging in for7days.