Preparation of Ultrafine Powder of ZrO2 with Impinging-Tubular Reactor
Abstract:
Zirconia industry in our country is under developing. During the past decades, a great number of low end ZrO 2 powder were exported, but on the contrary, many high grade ZrO 2 powder were imported simultaneously. For that cause, new technology to prepare ZrO 2 powder with high extra economic value, especially ZrO 2 nano-powder with controlled particle size and its distribution, is needed to develop urgently. Method of reaction precipitation is becoming the focus of the study because of its low cost and easy industrialization. In this paper, a new technology of tubular reaction with impinging inlet was investigated. Reaction precipitation occurred when reactants contacted each other by impinging, through which micromixing was greatly intensified to ensure a homogeneous environment. In this case, the nucleation can be controlled effectively. Moreover, tubular reactor provided a homogeneous environment for growth of nuclei because back mixing was avoided as possible. So, both nucleation and growth progress can be controlled. Combination with surface modification via alcohol-thermal treating, final ZrO 2 nano powder with 14 nm of mean particle size and very narrow size distribution and no agglomeration is achieved. All the processes are operated easily, and have a good prospect of industrialization.