Preparation And Properties Of Oil-water Separation Materials Via Surface Modification By Natural Phenols

The pollution of oily wastewater seriously threatens human health and the ecological environment.Therefore,effective oil-water separation of oily wastewater is a serious task at present.Among the numerous oil-water separation methods,the oil-water separation material has attracted more and more attention not only because of its selective absorption of water or oil,but also it has the advantages of high separation efficiency and no secondary pollution.How to use natural environmentally friendly,non-polluting materials or how to prepare oil-water separation materials with good performance by simple and inexpensive methods is the goal of this paper.Firstly,the cardanol-based benzoxazine monomer is synthesized by using the natural product cardanol with long carbon chain and formulated into a solution.Superhydrophobic fabric with a contact angle of more than 150°can be made in one step on different materials?cotton fabric,non-woven fabric and cotton?by solution immersion method,and different oil-water separation methods can be selected according to the characteristics of the material.Through a series of characterization and performance tests,it was found that the superhydrophobic cotton fabric and superhydrophobic non-woven fabric prepared by the method have good mechanical stability and chemical stability,and all of separation efficiency of various kinds of oils are above 94%.Especially the superhydrophobic cotton fabric not only can maintain high separation efficiency after repeated use,but also can efficiently perform oil-water separation even in extreme environments of strong acid,alkali or high salt.It has excellent properties such as high temperature resistance,ultraviolet radiation resistance and durability,too.Superhydrophobic cotton,because of its superoleophilic property,exhibits great adsorption capacity for different oils,and can separate oil-in-water emulsions successfully.Urushiol is a traditional coating in China.The main component is urushiol,which is a natural product with a long carbon side chain structure.We first constructed nano-scale TiO₂ particles on cotton fabric,then the phenolic hydroxyl groups of urushiol reacted with TiO₂ by solution immersion method to prepare modified cotton fabric with hydrophobic and oleophilic properties,the contact angle is about 146.13°.The cotton fabric exhibits excellent corrosion resistance and can not be corroded and permeated under the long-term infiltration of strong acid or strong alkaline aqueous solution of different concentrations,and it also shows great properties of friction resistance,high temperature resistance,UV resistance.When it is used for oil-water separation,all of separation efficiency of different oils are above 94%,and separating repeatedly does not affect the separation efficiency,even in the chemical environment of strong acid,strong alkali or high salt.It is a fabric material with excellent properties and is expected to be used for hazardous protection.