微波制备人造金红石及其相转变的研究

天然金红石是生产钛白粉的重要原料之一。目前,可利用的高品位天然金红石资源日渐枯竭,探索一种在较低能耗以及较小环境污染下生产人造金红石的方法已日趋迫切。微波加热技术现已广泛的应用于试验和工业生产中,与传统加热相比,有着选择性加热,加热速度快等优点。本文以云南高钛渣为原料提出一种微波加热制备高品质人造金红石产品的新工艺,并利用X射线衍射,扫描电子显微镜,能谱分析等方法对产物进行表征与分析。XRD分析结果表明,高钛渣的主要成分是铁钛氧化物的固熔体,其中的二氧化钛大多是以锐钛矿形式存在,也含少量的金红石相。经过微波焙烧后,锐钛矿的峰已经消失,金红石的峰增强。SEM-EDAX分析结果表明高钛渣表观型貌图中高钛渣颗粒表面比较光滑、平整,但经微波焙烧后物料生成了一些形状不是很规则的短棒状体,这些棒状体即为金红石相。

The investigation on the preparation of synthetic rutile and its phase transformation using microwave heating

Natural rutile is one of the important raw materials for the production of TiO₂ pigment. Nowadays the high grade natural rutile resource become limiting. So it is urgent to explore a new method with low energy consumption and less environmental pollution for the preparation of synthetic rutile TiO₂. Microwave heating technology has been widely used in both research and industrial processes. Compared with the traditional heating, microwave heating is selective and the speed of it is fast. In this paper, a new method with microwave heating is proposed to the preparation of synthetic rutile TiO₂. The crystal structure and microstructure were investigated by X-ray diffraction (XRD), scanning electron microscope-energy spectrum analysis (SEM-EDAX), respectively. XRD analysis results show that the main phase of high titanium slag is anosovite, accompanied with a small amount of anatase and rutile phase. After microwave roasting, anatase has disappeared, the peak of rutile increases. SEM-EDAX analysis results show that the surface of high titanium slag is smooth. After microwave heating, some irregular rod-like particles appeared which belongs to the morphology of rutile TiO₂