Preparation of rutile TiO2 by hydrolysis of TiOCl2 solution: experiment and theory
Preparation of rutile TiO2 by hydrolysis of TiOCl2 solution: experiment and theory
复制标题
TiOCl2 溶液水解制备金红石型 TiO2：实验与理论
DOI：
10.1039/c6ra04386k
复制
发表时间：
2016-01-01
期刊：
影响因子：
3.9
通讯作者：
Cao, Chengbo
中科院分区：
文献类型：
--
作者：
Liu, Yahui;Shao, Dawei;Cao, Chengbo
具有钙钛矿相（CaTiO 3）的钛渣难以用于传统的钛白粉生产。在此，我们证明了HCl可以以> 97wt%的高酸解率分解CaTiO 3以获得TiOCl 2溶液。通过水解和煅烧，一步合成了金红石型TiO 2，没有晶型结构的转变。由于TiOCl 2溶液水解制备偏钛酸（H2 TiO 3）是该过程中的关键步骤，因此通过拉曼光谱证实了模拟纯TiOCl 2溶液（由TiCl 4和H2O制备）在水中与HCl处理的CaTiO 3渣具有相同的结构。基于拉曼数据的DFT计算和水解率的曲线拟合，还推断出TiOCl 2溶液具有（Ti 2 O2）（H2O）4Cl 4的Ti化合物簇。通过阐明H2 TiO 3颗粒尺寸与Ti 4+和HCl浓度之间的关系，我们确定了核能为-19.46 kJ mol−1。此外，提出了一个完整的方案，为金红石型TiO 2，诱导水解TiO 2溶液，。周期性结构表明，通过简单的结构重排发生以下转变的可行性：（Ti_2O_2）（H_2O）_4Cl_4（在溶液中）-Ti（OH）（H_2O）_2Cl_3（添加HCl）-Ti（OH）_2Cl_2（一维生长和除去HCl）-金红石型Ti（OH）_2Cl_2（堆叠）-金红石型TiO_2（除去HCl）。
Titanium slag with a perovskite phase (CaTiO3) is difficult to use in traditional titanium dioxide production. Herein, we demonstrate that HCl can decompose CaTiO3 with a high acidolysis ratio of >97 wt% to obtain a TiOCl2 solution. With subsequent hydrolysis and calcination, rutile TiO2 was synthesised in one step without crystalline-structure transformation. As hydrolysis of the TiOCl2 solution to prepare metatitanic acid (H2TiO3) is an essential step in the process, a simulated pure TiOCl2 solution (prepared from TiCl4 and H2O) was confirmed to have the same structure in water as HCl-treated CaTiO3 slag by Raman spectroscopy. The TiOCl2 solution was also concluded to have the Ti compound cluster of (Ti2O2)(H2O)4Cl4, based on DFT calculations from the Raman data and the curve fit for the hydrolysis ratio. By elucidating the relationship between the H2TiO3 particle size and the concentration of Ti4+ and HCl, we identified the nuclear energy as -19.46 kJ mol−1. Moreover, a complete scheme for the production of rutile TiO2, induced by TiOCl2 solution hydrolysis, was proposed. Periodic structures show the feasibility of the following transformation occurring through a simple structural rearrangement: (Ti2O2)(H2O)4Cl4 (in solution)–Ti(OH)(H2O)2Cl3 (with addition of HCl)–Ti(OH)2Cl2 (1-dimentional growth and removal of HCl)–rutile-type Ti(OH)2Cl2 (stack)–rutile TiO2 (with removal of HCl).