Preparation of zirconia Nanopowder from the product of the acid washing stage of Alkali fusion of Zircon: investigation of the parameters of the preparation stage of zirconia Nanopowder by precipitation method
Subject Areas :
Yasaman Jalinousi
1
(Research Assistant, M.Sc. in physical chemistry, Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, Tehran, Iran)
Kamal Saberayn
2
(Associate Professor, Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, Tehran, Iran.)
Keywords: Zirconia, Nanopowder, Surfactant, Zircon, Alkali fusion,
Abstract :
The purpose of this research is to perform the process of extracting zirconium from zircon mineral by alkali fusion method and determining the optimal operating conditions for preparing zirconia nanopowder from the solution of the acid leaching step.Alkali fusion process of zircon includes three stages of melting zircon with alkali, water leaching and acid leaching.The final product obtained from the reaction of melting zircon with alkali has in the desired state a powdery form and includes sodium silicate and sodium zirconate.Sodium silicate is soluble in water and as a result it is removed from the powder after the water leaching step.In order to further enrich the powder and separate silica, unreacted zircon and other remaining impurities, this powder is leached by an acid.The optimal parameters of the steps of melting with alkali, washing and acid washing have been used from past researches to achieve the highest amount of zirconium and remove the largest amount of silica.In order to determine the optimal conditions for the production of zirconia nanopowder,the effect of pH, type and mass ratio of surfactant to zirconium and calcination temperature were investigated.The results of the investigations showed that the optimal conditions for the deposition stage are pH equal to 7,the polyvinyl pyrrolidone as a surfactant with a mass ratio of surfactant to zirconium of 0.82 and the calcination temperature of 300 degrees Celsius.Under these conditions, particles with dimensions of 27.1nm were obtained from artificial zirconium solution and particles with dimensions of 26.6nm were obtained from real zirconium solution.