TiC及びTiN粉末と高温高圧水との反応

概要

論文の詳細を見る
The reactions between TiC or TiN powder and H_2O have been studied at 200°-650℃ under 100 MPa. The reaction of TiC with H_2O above 400℃ for 3 h yielded anatase, CH_4, CO_2 and H_2, and above 500℃ rutile was formed additionally. TiN powder with an average grain size of 1.4/μm reacted with H_2O above 290℃ to yield anatase, NH_3 and H_2, while TiN powder of 9 μIm reacted H_2O above 480℃ and yielded rutile, NH_3 and H_2. The oxidation rate calculated from the weight gain was compared with that from various model kinetic equations. In TiC the rate was best described by the Avrami- Erofeev equation ( n =1.3), while the core-shrinking model fitted as well. This suggests that the reaction was controlled by the phase boundary reactions. In TiN the Jander-type model was the best, which suggests that the reaction was controlled by the diffusion through the oxide scale. An Arrhenius plot of the rate constants gave an apparent activation energy of 98 kJ/mol. The difference of reaction mechanism between TiC and TiN is attributed to the difference in the gaseous species of reaction products.
社団法人日本セラミックス協会の論文
1989-11-01