Study on a new, environmentally benign method and its feasibility of preparing nanometer zirconia powder

In this paper, a new method to prepare nanometer zirconia is described, and the mechanism is discussed briefly. It is proposed that the coordinated wa ter of zirconium oxychloride acts as a microzone actuating medium in the pr eparation of zirconia powder. The method was realized by agitating a solid mixture of sodium hydroxide and zirconium oxychloride, whose intermediate a nd final products were studied by X-ray fluorescence analysis (XRF), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and transmission electron microscopy (TEM). It was found that the nuclei of zirconia were f ormed under the superalkaline condition and polycrystallized at 400 degrees C. The experiments showed that the powder obtained was tetragonal/cubic zir conia, with narrow particle size distribution (average size about 7 nm), an d contained and less than a trace (<10 ppm) of chlorion. The by-product of the new process can be recycled as chemical raw material after simple treat ment. Compared with traditional methods, the new method is environmently be nign, with low energy consumption, convenient manipulation, easy source rec ycling, and low pollution. (C) 2000 Elsevier Science Ltd. All rights reserv ed.