Study On New Preparation Technology Of Nano Zirconia

This study researched improved process route of nano-zirconia in aqueous solution using zirconium oxychloride and urea as the raw materials. Factors that affects on process route were discussed through the selection of reaction temperature, urea solution concentration, reactants mol ratio, calcining temperature, dispersing method, drying method and surfactant, and the optimum technological conditons were determined through orthogonal experiment. Univarite regression analysis and bis-factor regression analysis were used to forecast the optimum value, and the zirconia powder was characterized by environmental scanning electronical microscope(ESEM) and laser particle size distribution analyzer(LA).The research showed that there was no need to do ball milling after spray drying. surfactant has no effect on the particle size of powder. it mainly affects the crystal form of product. Monoclinic zirconia powder was prepared by Span80 or OP-10 as dispersant, while tetragonal zirconia powder was prepared by organic polymer polyvinyl alcohol (PVA) or polyethylene glycol (PEG) which possess high molecular weight and long chain as dispersant.The optimal synthesizing conditions were found through monofactor experiment, univarite regression analysis, bis-factor regression analysis and orthogonal experiment when the reaction temperature was 100℃, urea solution concentration was 13%, reactants mol ratio was 2:1, the precusor was calcinated completely at 550℃, the best drying method was spray drying. Under the above conditions, the verification test was carried out by adding OP-10 as dispersant, and the dispersion of zirconia powder were characterized by ESEM and LA, respectively, the result showed that the average particle size was 113.5nm with a good distribution, and the expected target had achieved.