| Oil pollution in water bodies is seriously endangering people’s health and the ecological environment,so it is necessary to develop high absorption rate,reusable,environmentally friendly and renewable adsorption materials.Bacterial cellulose（BC）aerogel is an ultra-light,porous,and degradable three-dimensional material,and its extremely high adsorption properties make it have broad application prospects in the treatment of polluted wastewater;graphene oxide（GO）as a new type of carbon The material has the advantages of high porosity,high specific surface area,high mechanical strength,and easy surface modification,which can improve the mechanical properties of the material and can also be used for dye adsorption.Therefore,bacterial cellulose-based aerogels are ideal oil adsorbents after proper mechanical reinforcement and hydrophobic modification.This study is mainly divided into three parts:（1）Using BC as the base material,aerogels were prepared by freeze-drying technology,and the surface morphology,chemical structure,and pore structure of BC aerogels with different BC concentrations,solution p H,and alcohol replacement were investigated.,the influence of thermal properties,the aerogel with the best BC concentration and solution p H was obtained;（2）On the basis of the above,the chemical reaction between butane tetracarboxylic acid（BTCA）and the hydroxyl group on the BC molecule was used for cross-linking,freeze-drying After the preparation of aerogel,the cross-linked BC aerogel was prepared by high temperature and short time treatment.The effect of BTCA addition on the surface morphology,chemical structure,pore structure,thermal properties and mechanical properties of BC aerogel was investigated.The cross-linked BC aerogel was tested.The oil absorption performance and recycling performance of the cross-linked aerogel were characterized,and the optimal addition amount of cross-linking agent was obtained;（3）In order to further increase the mechanical properties,recycling performance and oil absorption performance of the cross-linked BC aerogel,adding GO,to explore the effect of GO addition on the surface morphology,chemical structure,pore structure,thermal properties,and mechanical properties of BC aerogels,and to obtain the optimal GO addition amount,hydrophobic modification of the composite aerogel by vapor deposition,adjustment modification time.The hydrophobic properties,oil absorption properties,recycling properties and oil-water separation properties of the composite aerogels were tested and characterized.The results show that: when the BC concentration is 0.7 %,the p H of the solution is 4,the tert-butanol is replaced,the BC/BTCA/GO ratio is 100/10/5,and the hydrophobic treatment time is 3.5 h,the three-dimensional lamellae inside the cross-linked composite aerogel are obtained.The structure is uniform,no crystal particles are precipitated,the linear shrinkage rate is as low as 5.88 %,and the porosity is as high as 99.9 %.The specific surface area and pore volume are greatly improved,and the average pore size is reduced from 28.2nm to 1.9 nm;The gel is greatly improved,the mass residual rate increases from 15.9 % to41.5 % at 600 ℃,and the maximum thermal degradation temperature increases from 285 ℃to 331 ℃;it has a good compression cycle.After 10 times of compression at 50 %,its maximum The compressive stress is 20.2 k Pa,and the compressive structure is still stable in water;when the hydrophobic treatment time is 3.5 h,the hydrophobic effect is better,and the contact angle reaches 152 °;The adsorption efficiencies of edible oil were 51 g/g,50 g/g,45g/g,79 g/g,204 g/g,131 g/g,and 106 g/g,respectively.The extraction cycle of ethanol was relatively high.After 20 extraction cycles,the adsorption capacity is only reduced by 14.8 %,and the adsorption capacity of the paraffin oil is only reduced by 38 % after 20 compression cycles.At the same time,it can quickly absorb the oil on water and underwater,and has a good oil-water separation effect. |
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