碳热还原法制取Ti(C,N)的热力学原理

分析了以TiO2为原料，用碳热还原法制取Ti（C，N）的热力学原理。结果表明钛氧化物的还原是逐级进行的，反应过程伴随着相变，当TiO2粉末和C粉末均匀混合时还原碳化反应主要依赖于CO／CO2传质的气固反应，当TiO2颗粒表面被C包膜时主要是碳和钛氧化物之间的固固反应，当TiO2粉末和C粉末混合压球时则两种反应机理均有。升高温度有利于还原进行，钛氧化物的开始还原温度随气相中的CO分压降低而降低。Ti（C，N）中的C，N含量取决于温度和N2压力。

Thermodynamic principle of preparing Ti(C, N) by carbon-heat reducing

Thermodynamic principle of making Ti(C,N) with TiO_2 by carbon-heat reducing is analyzed.The result shows that synthesizing process goes along with phase change,the reducing of titanic oxide goes along gradually.When TiO_2 powder and carbon grain are mixed,the reductive and carbonized reaction mainly depend on CO/CO_2 gas-solid reaction.When surface of TiO_2 powder is enveloped by carbon,the reduction is mainly solid-solid reaction between carbon and titanic oxide.When TiO_2 powder and carbon grain are mixed and pressed into globosity,the reduction is either gas-solid or solid-solid reaction.It is beneficial to reducing process to increase temperature.The reduction initiative temperature of titanic oxide decreases with decrease of partial pressure of CO.But the content of C,N in Ti(C,N) depends on the temperature and partial pressure of N_2.