锐钛矿型氧化钛在高钙体系下的反应行为

对锐钛矿型Ti O2在高钙体系下的反应进行了热力学和动力学分析,确定了理论上能发生的反应,计算了活化能和反应级数并判断出反应控制类型.通过实验研究了锐钛矿型Ti O2在Ti O2-Ca O-Na Al O2体系下的反应行为.结果表明,在Ti O2与Ca O物质量的比为1,反应1 h,铝酸钠溶液中Na2O的质量浓度为220 g/L,Na2O与Al2O3物质量的比为3.1的条件下,随着温度的升高,首先Ti O2与Na OH反应生成Na2Ti O3,Ca(OH)2和Na Al(OH)4反应生成3Ca O·Al2O3·6H2O,反应产物3Ca O·Al2O3·6H2O与Na2Ti O3反应最终可以得到稳定的Ca Ti O3.锐钛矿型Ti O2可在220℃以上完全转型为Ca Ti O3,升高温度能促进钛向最终物相Ca Ti O3的转型.

Reaction Behavior of Anatase Titanium Oxide in High Calcium System

Thermodynamic and kinetics analysis of anatase TiO₂ reaction in high calcium system were conducted and the possible reactions were determined. Activation energy， reaction order and reaction control types of important reactions were determined by calculation in this system. The reaction behaviors of anatase TiO₂ in TiO₂-CaO-NaAlO₂ system were investigated through experiments. The results showed that when the molar ratio of TiO₂ and CaO is 1， the reaction time is 1h， the mass concentration of Na₂O is 220g/L， the molar ratio of Na₂O and Al₂O₃ is 3.1， TiO₂ reacts with NaOH to produce Na₂TiO₃ first， then Ca(OH)₂ and NaAl(OH)₄ react to produce 3CaO·Al₂O₃·6H₂O with increasing temperature. The resultant 3CaO·Al₂O₃·6H₂O reacts with Na₂TiO₃ to get stable CaTiO₃. Anatase TiO₂ converts to CaTiO₃ completely at 220℃. In this process， elevating temperature can promote the conversion of anatase to the final phase of CaTiO₃.