均匀设计在沉淀法制备纳米二氧化锆中的应用

用氨水作沉淀剂与氯氧化锆进行反应生成的胶体沉淀再焙烧制备出纳米二氧化锆。利用均匀设计考察了反应物量比、反应物浓度、焙烧温度和焙烧时间对产品平均粒径、分散性和晶形状态的影响。粒径由TEM测出 ,分散性和晶形状态由人为评分给出。研究表明反应物量比、氯氧化锆浓度和焙烧温度对产品性质影响较大。本实验优化的制备条件是 :n(氨水 )∶n(氯氧化锆 ) =3∶1;c(氯氧化锆 ) =0 .1mol/L ;c(氨水 ) =0 .5mol/L ;焙烧温度为 6 0 0℃ ;焙烧时间为 1h ,在此条件下可获得均匀分散的纳米二氧化锆 ,收率为 95 .4%。XRD分析结果表明 ,此产品主要为单斜晶形

Application of Uniform Design to Preparation of Nano ZrO_2 by Precipitation

Aqueous ammonia as precipitant reacts with ZrOCl\-2·8H\-2O at room temperature and the resulting colloidal precipitate is calcinated to give nano ZrO\-2 powder.By means of uniform design,the influences of molar ratio and concentrations of reactants,calcinating temperature and time on average size,dispersity and crystal form of the product are investigated.The result of study indicates that properties of the product are greatly affected by the molar ratio of reactants,concentration of ZrOCl\-2 and the calcinating temperature.The optimum conditions for the preparation of nano ZrO\-2 powder are n (NH\-3·H\-2O)∶ n (ZrOCl\-2)=3∶1, c (ZrOCl\-2)=0.1 mol/L, c (NH\-3·H\-2O)=0.5 mol/L,calcinating time 1 h and calcinating temperature 600 ℃.Under these conditions well distributed nano ZrO\-2 is obtained.The product yield is up to 95.4%.Result of X ray diffraction shows that the crystal form is monoclinic.