不同形貌γ-AlOOH的制备及刚果红吸附试验研究

Preparation of Different Morphology of γ-AlOOH and Their Adsorption Performance to Congo Red in Water

以硝酸铝为铝源、尿素、硫酸钠、十六烷基三甲基溴化铵为沉淀剂,采用水热法分别合成空心微球、针状和层状的γ-AlOOH。通过X射线衍射(XRD)、扫描电子显微镜(SEM)和N_2吸附-脱附技术对γ-AlOOH样品进行表征测试。结果表明:3种不同形貌的γ-AlOOH均为正交晶相,其中空心微球状具有分等级孔结构,比表面积最大,达到82.5m^2·g^(-1),吸附量最大,达到504.54mg·g^(-1);而针状和层状主要为狭缝型孔结构。3种样品对刚果红动力学吸附数据符合准二级动力学模型和离子内扩散模型,热力学吸附数据符合Langmuir等温线模型。

Hollow microspheres,needle-like and lamellar γ-AlOOH were synthesized by hydrothermal method,respectively,using aluminium nitrate as precursors and urea sodium sulfate and CTAB as precipitating agent.The structure,morphology and textural properties of the γ-AlOOH samples were characterized by X-ray diffraction,scanning electron microscopy and N_2 adsorption-desorption techniques.It was found that all samples were orthorhombic γ-AlOOH;γ-AlOOH hollow microspheres had unique hierarchically porous structure and high specific surface areas（82.5m^2·g^-1）;It exhibited excellent sorption capacity（504.54mg·g^-1）for Conge red;Needle-like and lamellar γ-AlOOH were mainly of slit-shape porous structure.The pseudo-second order and intra-particle diffusion model could describe the adsorption kinetics.The Langmuir model showed the better correlation of the experimental data.