微混合沉淀技术制备纳米TiO2颗粒

以Ti(SO4)2为分散相，NH4HCO3为连续相，通过膜分散实现液液的微混合沉淀，从而制备纳米TiO2晶体颗粒、分别研究了两种反应物浓度和流量对制备的TiO2颗粒的影响，并利用XRD和TEM分别对所得颗粒的晶型和形态进行了表征．实验结果表明，制得的颗粒具有球形度高，粒径小，分布范围窄，且为锐钛矿结构的特点．TiO2的晶粒粒度和颗粒粒径随Ti(SO4)2和NH4HCO3浓度的上升，先有所上升再下降；随Ti(SO4)2流量的上升而下降；随NH4HCO3流量的上升而上升．微混合沉淀技术是一种很好的控制颗粒粒径、且连续化沉淀制备TiO2超细颗粒的新方法。

Preparation of Ultra-fine TiO2 Particles Using Micro-Mixing Precipitation Technology

A method of micro-mixing-precipitation technology was developed from membrane dispersion technology to prepare ultra-fine TiO2 particles. Titanic sulfate was selected as the dispersed phase, and ammonium acid carbonate as the continuous phase. The influences of the re-actant concentrations and two-phase flow rate were investigated. The crystal structure and crystal dimension of the particles were analyzed by XRD, morphology, particle size and size distribution by TEM. The results showed that the spheric TiO2 nano-particles with small size and narrow size distribution could be prepared with the method. The crystal dimension and the particle size of the Ti02 particles were increased with the increasing of reactant concentrations at first, then decreased. They also were decreased with the increasing of the flow rate of Ti(SO4)2 solution, but increased with the increasing of the flow rate of NH4HCO3 solution.