Preparation Of Functional Cotton Fabric Based On CuO And Its Application In Water Purication

With the continuous advancement of human industrialization,the lack of drinking water,the discharge of industrial sewage,and the frequent occurrence of crude oil spills have brought huge threats to human's life and health and the global ecological environment.Therefore,the development of multifunctional water purification material that can remove bacteria,organic pollutants and oil-soluble pollutants is the current research hot spot and focus in the field of materials and environment.Based on the physical and chemical properties of copper oxide(CuO),cotton fabric/copper oxide composite(Cot-CuO)was prepared by in-situ growth of cotton fabric(Cot)and copper acetate(CuAc)as raw materials and explore its potential to remove bacterial and soluble dyes in water.On this basis,the stearic acid(STA)hydrophobic surface was constructed by impregnating the surface of the Cot-CuO composite material to obtain cotton fabric/copper oxide/stearic acid superhydrophobic material(Cot-CuO-STA),and further explore its separation performance for oily pollutants in water.On this basis,Cot-CuO and Cot-CuO-STA were assembled into a double-layer functional membrane system(DFMS),and the oil-water separation efficiency and photocatalytic performance of DFMS on complex water containing both oil CHCl3 and methylene blue(MB)water-soluble dye were investigated.The specific research work is as follows:(1)Preparation of cotton fabric/copper oxide composite and study on their antibacterial and photocatalytic properties:cotton fabric/copper oxide composite(Cot-CuO)were prepared by in-situ growth using cotton fabric(Cot)as the substrate and copper acetate(CuAc)as the precursor solution.The effects of CuAc concentration on the micro-morphology,crystal structure,and loading of CuO were studied,and the ability of Cot-CuO to remove bacteria and soluble dyes in water was investigated.Cot-CuO was characterized by X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM),X-ray diffractometer(XRD)and thermogravimetric analyzer(TGA).The results of XRD and SEM show that the micro-nano particles deposited on the surface of cotton fabric are CuO phase,CuO particles are concentrated into a subsphere by small particles with the increase of CuAc concentration and the particle accumulation becomes denser.TGA analysis showed that the load of CuO on cotton fabric surface increased significantly from 0.8%to 15.9%with the increase of CuAc concentration from 0.5%to 3%.Cot-CuO with high load showed excellent antibacterial activity:when the dosage of Cot-CuO3.0 was 1 mg·mL-1,it acted on 106 CFU·mL-1 Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)for 2 h,showing 100%high antibacterial property.In particular,the growth and reproduction of microorganisms in river water also showed a complete inhibition effect.In addition,Cot-CuO3.0 showed a good visible light catalytic degradation potential for MB:the visible light catalytic degradation rate of 10 mg·L-1 MB reached.62.7%,further expanding the application potential of Cot-CuO3.0 for photocatalytic degradation of organic dyes.(2)Preparation of cotton fabric/copper oxide/stearic acid superhydrophobic material and study of its oil-water separation performance:Based on the rough surface of cotton fabric/copper oxide composite(Cot-CuO),stearic acid(STA)with low surface energy was coated on the surface of Cot-CuO by the dipping method to prepare cotton fabric/copper oxide/stearic acid superhydrophobic material(Cot-CuO-STA).The effects of the concentration of CuAc and the number of impregnations on the micro-morphology of the material and the water contact angle were studied.It was found that the treatment with CuO significantly increased the adhesion of stearic acid on the surface of cotton fabrics,and the coating amount increased with the increase of CuAc concentration;the increase of impregnation times also significantly improved the hydrophobicity of the fabric surface.Based on comprehensive economics and timeliness,the Cot-CuO-STA preparation process was determined as follows:CuAc concentration was 2 wt%,and cyclic dipping was performed 5 times.The obtained Cot-CuO-STA has excellent superhydrophobic characteristics with a water contact angle of 156.5°,and it has good chemical and mechanical friction stability.Soaked in pH 5?9 and 0.9?2.5 wt%NaCl solution for 6 days,it still maintains its superhydrophobic property;after high temperature treatment at 100?200?,its water contact angle is still above 156°;after rubbing for 20 cycles with 1500 mesh sandpaper,the water contact angle remained above 150°,showing excellent hydrophobic stability.The results of oil-water separation performance research show that the Cot-CuO-STA superhydrophobic material has a separation efficiency of more than 98.7%for n-hexane(C6H14)soybean oil,dichloroethane(CH2Cl2)and trichloroethane(CHCl3).In particular,after 10 cycles of testing,the oil-water separation efficiency remained at 97%.The permeate flux to CH2Cl2/H2O and CHCl3/H2O mixture was as high as 1740 L·m-2·h-1 and 1805 L·m-2·h-1,and remained at 1666 L·m-2·h-1 after 10 cycles,maintaining 92%of the original permeate flux.At the same time,Cot-CuO-STA also show excellent antifouling and self-cleaning capabilities?On this basis,the photocatalytic activity of Cot-CuO and the oil-water separation performance of Cot-CuO-STA were organically combined to construct a double-layer functional membrane system(DFMS);showed a separation efficiency of at least 93.6%for oil CHCl3/MB aqueous solution,a permeate flux of up to 1975.4 L·m-2·h-1,and a photodegradation efficiency of 70.1%for MB.DFMS demonstrated the potential as a complex water purification material.In this paper,CuO functionalized cotton fabric was successfully prepared by simple in-situ growth and impregnation coating technology,which could remove microorganisms,soluble dyes and oil pollutants in water simultaneously.The research in this paper is simple,gentle,cheap and easy to obtain raw materials,and easy to achieve large-scale production.It provides a certain theoretical basis and experimental reference for the development of multifunctional water purification materials and its application in the purification of complex water.