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本文用X射线粉末衍射仪考察了从ZrCl_4和ZrOCl_2·8H_2O出发，经过不同的处理，制备出不同晶型的ZrO_2。讨论了影响四方ZrO_2生成的实验条件。实验结果表明：ZrCl_4在空气中水解并热分解后能够得四方ZrO_2，其最佳焙烧温度为320—350℃，该温度下焙烧制得的四方ZrO_2颗粒大小为300 ，比表面为99．2m~2／g焙烧温度更高时，四方ZrO_2逐渐晶化为单斜ZrO_2。ZrCl_4或ZrOCl_2·8H_2O氨解后得到的Zr（OH）_4在高温焙烧过程中Clˉ，OHˉ，NH_4~+等杂质离子存在不利于四方ZrO_2的生成。而Fe（NO_3）_3·9H_2O，Ni（NO_3）_2·6H_2O等浸渍盐的存在和混合r—Al_2O_3载体，水解、焙烧后极大地有利于四方ZrO_2形成。
In this paper, X-ray powder diffractometry was used to investigate the different crystalline forms of ZrO_2 from ZrCl_4 and ZrOCl_2 · 8H_2O. The experimental conditions affecting tetragonal ZrO 2 formation were discussed. The experimental results show that ZrCl_4 is tetragonal ZrO_2 after being hydrolyzed and pyrolyzed in the air, the optimum calcination temperature is 320-350 ℃, the size of the tetragonal ZrO_2 calcined at 300 ℃ and the specific surface area is 99.2m ~ When the calcination temperature is higher than 2 / g, the tetragonal ZrO 2 gradually crystallizes into monoclinic ZrO 2. The Zr (OH) _4 obtained after the ammonolysis of ZrCl_4 or ZrOCl_2 · 8H_2O is not conducive to the formation of tetragonal ZrO_2 during the calcination at high temperature. However, the presence of Fe (NO_3) _3 · 9H_2O, Ni (NO_3) _2 · 6H_2O impregnated salts and the mixed r-Al_2O_3 support, hydrolysis and calcination greatly contribute to the formation of tetragonal ZrO_2.