Fe_3O_4@SiO_2复合气凝胶的制备及其对刚果红的吸附

Preparation of Fe_3O_4@SiO_2 composite aerogel and its adsorption to Congo red

以Fe Cl_3·6H_2O和正硅酸四乙酯为原料,通过溶胶-凝胶法结合醇溶剂热法制备了Fe_3O_4@Si O_2复合气凝胶。采用XRD,FTIR,SEM,EDS等技术对Fe_3O_4@Si O_2的结构进行了表征。考察了Fe_3O_4@Si O_2对刚果红溶液的吸附性能。表征结果显示,Fe_3O_4@Si O_2复合气凝胶是由直径为10~20 nm的近球形颗粒组装而成的具有三维网络结构的纳米材料,比表面积为457.93 m^2/g,平均孔径为10.7 nm。在溶液p H为5、吸附时间为35 min的最佳工艺条件下,采用Fe_3O_4@Si O_2吸附处理质量浓度为10 mg/L的刚果红溶液,刚果红去除率为99.39%,此时溶液中刚果红的质量浓度仅为0.052 mg/L。Fe_3O_4@Si O_2复合气凝胶吸附刚果红后具有较好的解吸和再生能力。

The Fe3O4@SiO2 composite aerogel was prepared by sol-gel method combined with alcohol solvothermal method using FeCl3 · 6H2O and tetraethylorthosilicate as raw materials. The structure of Fe3O4@SiO2 was characterized by XRD, FTIR, SEM, EDS, etc. The adsorption capability of Fe3O4@SiO2 to Congo red （CR） was studied. The characterization results indicate that： The Fe3O4@SiO2 composite aerogel is a kind of nano material with three- dimensional network structure, which consists of subglobular particles with 10-20 nm of diameter; The specific surface area of Fe3O4@SiO2 composite aerogel is 457.93 m2/g, and the average pore size of it is 10.7 nm. Under the optimum process conditions of solution pH 5, adsorption time 35 min and mass concentration of CR 10 mg/L, the CR removal rate is 99.39% and the mass concentration of remaining CR in solution is only 0.052 mg/L. The desorption and regeneration abilities of the used Fe3O4@SiO2 composite aerogel are good.