湍流效应是火焰合成纳米TiO2颗粒工业化规模放大的一个重要影响因素。本文基于一种新提出的滞止旋流火焰开展了合成TiO2纳米颗粒的实验研究。在旋流数0.26的条件下,可成功获得比表面积300 m~2/g以上,粒径最小达5nm的锐钛矿型TiO2颗粒,这可归因于本文滞止旋流火焰具有贫燃稳定性、速度高反应快、温度梯度大等特点。实验还发现,随着前驱物浓度的减小,合成颗粒粒径逐渐减小且更加均匀。
Turbulence effect plays an important role in the scale-up and industrialization of flame synthesis process.In this paper,a swirl-stabilized stagnation flame was specially proposed and developed for the flame synthesis of TiO2 Nano-particles.After experimental researching,the obtained titiania from this process has a diameter of 5nm,BET surface more than 300 m~2/g with dominating anatase crystal due to the high temperature gradient,high flame speed and reaction of this novel flame.The results incidated that,with a smaller precursor loading rate,the particle diameter become smaller and more uniform.