反相微乳液法制备纳米氧化铝

采用由环己烷、聚乙二醇辛基苯基醚(TritonX-100)、正丁醇与水溶液构成的反相微乳液体系, 合成了纳米Al2O3粉体. 采用X射线衍射、扫描电子显微镜、透射电子显微镜、比表面积分析仪等表征手段, 分别对产物的结构、形貌、比表面积和孔容进行了表征, 该纳米Al2O3比表面积约450 m2·g-1(随反应参数不同发生变化), 均属γ-Al2O3, 粒径均匀, 颗粒直径小于10 nm. 考察了微乳液体系中水与表面活性剂的物质的量之比r0、表面活性剂与助表面活性剂的体积比φ、焙烧温度等关键因素对产物比表面积等物理性质的影响. 结果表明, 当r0=20, φ=0.5, 焙烧温度为500 ℃时, 可以得到大比表面积、高孔容、分散性好及粒径分布均匀的γ-Al2O3粉体.

Preparation of Nano-Alumina by Reverse Microemulsion Method

Al_2O_3 nanoparticles were prepared by reverse microemulsion method that uses cyclohexane, polyethylene glycol octylphenyl ether (TritonX-100), n-butylalcohol, and water. The structure, morphology, and specific surface area of the nano-alumina particles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and specific surface area analysis. The specific surface area of the nano-alumina particles was about 450 m~2·g~(-1) (changing with different reaction parameters) and the crystal structure was γ-Al_2O_3. The particle size was smaller than 10 nm and very uniform. The effect of molar ratio of water to surfactant (r_0), volume ratio of surfactant to assistant-surfactant (ψ), and calcination temperature (T) on the characteristics of the product were studied. The results indicated that the nano Al_2O_3 powder with a high specific surface area, high pore volume, good dispersibility, and narrow particle size distribution was obtained at r_0=20, ψ=0.5, and T=500℃.