高纯活性纳米γ型氧化铝的化学沉淀法合成及其性能表征

Synthesis and Characterization of High Pure Active γ-Al_2O_3 Nanoparticles by Chemical Precipitation Method

以硝酸铝为原料,碳酸铵为沉淀剂,通过加入少量表面活性剂,采用化学沉淀法获得前驱体,经热处理得到高纯活性γ型纳米氧化铝。研究了合成过程中的工艺影响因素,并使用DTA、XRD、BET、TEM、激光粒度及纯度分析等多种方法对γ-Al_2O_3的性能进行了表征。结果表明,所获得的γ-Al_2O_3属立方晶系,空间群为O_H^7—FD3M,原生晶粒平均尺寸为9nm左右,颗粒粒径为20nm左右,粒子大小分布均匀,比表面积为131.35m^2/g,孔径分布为7～11nm,纯度不低于99.93％。采用该法制备高纯活性纳米γ-Al_2O_3,具有原料价格便宜,设备及操作过程简单,能有效除去杂质,粒子分散性好、环境污染小等优点,从而具有较好的工业化发展前景。

High pure active γ-Al_2O-3 nanoparticle is synthesized from aluminium nitrate and ammonium carbonate with a little of surfactant by chemical precipitation method. The effect of the process is studied. This kind of γ-Al_2O_3 is characterized by using a variety of test methods, such as DTA,XRD,BET,TEM,laser granularity analysis and purity analysis. The result shows the crystal system of this γ-Al_2O_3 nanoparticle is cubic, with the space group being O^7h-FD3M, average primary crystal size about 9nm, particle size some 20nm and well-distributed, BET surface area 131. 35 m^2/g, pore size 7～11nm, and purity not lower than 99. 93%. In using this method to prepare high purity γ-Al_2O_3 nanoparticle, there are superiorities such as cheap raw materials, simple equipment and easy operation,effective exclusion of impurities, well-distributed particles and less environmental pollution. This offers a better prospect of industrialized development.