Fabrication Of Multifunctional Biomaterial-based Oil-water Separation Materials For Wastewater Treatment

The main pollutants of water include insoluble oil and soluble dyes.If we drink polluted water or eat plants and animals which feed on wastewater,it could cause serious damage to human health,and most of soluble dyes have deformed biological toxicity and carcinogenicity.In recent years,because of the bionic interface oil-water separation materials have high treatment efficiency,it has attracted widespread attention.While the single function of oil-water separation materials can be difficult to deal with toxic pollutants of the water.Biomaterials materials such as cellulose and lignin are renewable resources,and biomaterials materials have the advantages of environmental friendliness.This paper used biomaterials as based material to made functional oil and water separation material for efficient separation of oily water and treatment of dye in water.The main contents of the study are as follows:(1)We reported a hierarchical composite-coated cotton fabric coated with urchinlike Nix Py,aiming at dealing with complex water pollution.This cotton fabrics were fabricated though a simple and fast method to achieve interfacial degradation of watermiscible toxic organic pollutants and effective oil/water separation simultaneously.The results show that the composite-coated cotton fabric has obtained the stable superhydrophobic surface which could apply on oil/water separation.More interestingly,the micro/nanostructures could be maintained completely and kept long-term water repellency even after the abrasion test by sandpaper because of the flexibility of PDMS on the cotton fabrics.4-nitrophenol(4-NP)could be reduced to 4-aminophenol(4-AP)in the presence of Na BH4 due to the high catalytic ability of the cotton with the urchin-like Nix Py loaded on.This multi-function cotton composites allow continuous treatment of oily wastewater,making it a promising candidate for water purification.(2)We choose cotton as the raw material to fabricate cellulose aerogels through solgel method and Freeze drying.Then,dipped the aerogel in silver nitrate and polyvinyl alcohol(PVA)solution,with glutaraldehyde(GA)as crosslinking agent to improve the hydrophilicity of cellulose aerogel.Ag/Ag Cl was loaded onto cellulose aerogel by chemical precipitation and UV-irradiation.The structure and properties of superhydrophilic cellulose aerogel were characterized by SEM,XRD,FT-IR,XPS and contact angle test.The load of Ag/Ag Cl increases the roughness of the material so that the material has the properties of superhydrophilic and underwater superoleophobic.The oil/water separation efficiency of this material for different kinds of oil is more than 95%,and the oil/water separation efficiency of this material is higher than 95% for 10 cycles.We also investigated the self-cleaning properties of the materials.Due to the high catalytic activity of Ag/Ag Cl,the degradation rate of Rh B reached 91.8% within 20 minutes under sunlight.These properties show that the material has an important application prospect in water purification.(3)We choose populus euphratica wood as the base material,and the reduction of the wood was used to prepare silver loaded wood by one-step hydrothermal method.The internal structure of wood was characterized by SEM.It was found that there was a connected channel in the interior of the wood,and there was a nanoscale pore structure in the inner wall of the channel.Through XRD,XPS and contact angle test,it has proved that wood acts as the reductant in the hydrothermal condition to reduce Ag+ to Ag,and leak out its own amino group to improve the hydrophilicity of the material.Because of the special structure of the wood of,the nanocomposite has a good demulsification ability for small particle size(particle size of 0.5~1 ?m)and increases the possibility of contact between the catalyst and water soluble toxic organics.The catalytic conversion rate of MB was 97.21% in 5 min.The conversion rate of MB remained above 90% for 5 cycles The results show that the composite can be used for emulsified oil separation and catalytic decomposition.