Preparation And Adsorption Properties Of Waste Newspaper Based Cellulose Composite Aerogels

The wastewater are discharged from textile industry,printing,leather industry and chemical industry contains insoluble oils and soluble dyes,which are complex in composition,highly toxic,difficult to degrade with natural conditions,seriously damage the environment and cause many human diseases.Wastewater purification has become one of the urgent problems to be solved to protect the ecological environment.The adsorbent technology is simple in process and low in energy consumption,which has attracted the attention of many scholars due to its variety and excellent performance.Aerogels belong to porous adsorption materials,which have wide applications in oil cleaning and sewage purification.However,lower adsorption efficiency limits the practical application.In order to improve the oil absorption performance of aerogels and take into account the environmental protection and economic benefits,the cellulose aerogels(WA)with light porosity and high porosity were prepared from waste newspaper as raw material.On this basis,hydrophobic waste newspaper cellulose aerogels(WTA)were obtained after modification by methyltrimethoxy silane(MTMS).SEM showed that WA belongs to a three-dimensional interlaced network with large specific surface area.FTIR and XRD showed that hydrophobic groups were successfully introduced into the surface of WE after modification.Oil-water mixture can be separated in 20s.The maximum adsorption increment and adsorption capacity of GS-1 pump oil can reach 961.4%and 11.4 g/g,which is 3-4 times higher than that of WA.The adsorption capacity can still reach 7.4 g/g after four cycles of oil absorption,so it can be used as a potential oil absorption material.WE/GNS(WNS)and WE/GO(WOS)composite aerogels were prepared from waste newspaper cellulose(WE)by adding different mass fraction of graphene(GNS)and graphene oxide(GO).The hydrogen bonding force formed by GO or GNS and WE make the composite aerogels have multi lamellar morphology and strong stability.Due to the difference of surface electronegativity between GO and GNS,there are significant differences in the adsorption of MB and CR.When 0.5%w/v GO was compounded,the electrostatic force of WA on MB increased the adsorption capacity from 65.4 to 154.1 μmol/g,while the charge repulsion force between GO and CR only increased to 70.2%.The corresponding WNS obtained almost invariable adsorption amount in MB,but the π-π bond force between GNS and CR made the adsorption amount reach 128.6 μmol/g,which is 2.4 times as much as that of WA.Dye adsorption conforms to Langmuir isotherm,pseudo-second-order kinetics and internal diffusion model.As a new type of composite adsorbent,WNS and WOS can remove anionic and cationic dyes from wastewater to meet the needs of practical application.