| CeO2is a well-know rare earth oxide, because cerium dioxide has high chemical stability, unique store oxygen function, high dielectric constant, good ultraviolet absorption. Cerium dioxide has a wide range of applications including polishing materials, catalysts, ultraviolet blockers and solid oxide fuel cells. At present, the study of cerium dioxide mainly concentrated in the preparation and application. The research of crystallization kinetics is relatively lack. In this paper, the crystallization kinetics of cerium dioxide was studied by continuous steady state. It provides a theoretical basis for controllable preparation of cerium dioxide with this equation.In this research, Cerium dioxide was prepared by liquid precipitation method, and cerium nitrate was cerium source, ammonium carbonate was the precipitating agent, PEG6000was the addition agent. Method of continuous steady state was applied in the crystallization kinetics of cerium dioxide to obtain a model equation for controllable preparation of cerium dioxide. Experimental results demonstrated the reliability and validity of the model equation, which could provided a theoretical basis. Test Cerium dioxide by XRD, SEM, TEM, TG and particle size analyzer.The results showed that from the equation we could be deduced that growth rate G of crystal was slower with the increase of reaction temperature, and the nucleation rate B0of crystal was faster with the increase of reaction temperature, the equation of the growth rate and nucleation rate is:B0=4.60×10-12G-2.56. When the amount of additive PEG6000was increasing, the growth rate G of crystal was faster and the nucleation rate B0of crystal was slower. The equation of the growth rate and nucleation rate is: B0=6.95x10-23G-3.55. That microscope photos were in good agreement with the experimental results. Cerium dioxide of threadiness, long iron, stub was preparation by crystallization kinetics, to realize the controllable preparation of cerium dioxide. |
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