Study of the oxidation kinetics of vanadium carbide
Study of the oxidation kinetics of vanadium carbide
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DOI：
10.1007/bf00611690
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发表时间：
1975-10
影响因子：
2.2
通讯作者：
C. Santafé;C. Borgianni
中科院分区：
文献类型：
--
作者：
C. Santafé;C. Borgianni
钒的碳氧化物VO0.6C0.7和碳化钒VC 0.98的氧化反应在800° C的温度下进行了非热研究，在400 ° C和580° C之间进行了等温研究，氧压范围为10− 2到1 atm。碳氧化物在450° C以下遵循抛物线速率定律，V2 O 5是唯一的反应产物。活化能为49千卡/摩尔。VC 0.98在此温度范围内不形成氧化物，而是形成溶解氧，活化能为26.6千卡/摩尔。没有氧压的动力学依赖性被发现在此温度范围内的任何样品。两种样品在500-580° C范围内的氧化过程均遵循立方速率定律，在此过程中有V2 O 5生成。有一个P1/3依赖性和活化能是相同的两种材料，51千卡/摩尔。立方速率定律和正压依赖性（而不是预期的负依赖性）归因于与化学吸附在V2 O 5薄层上的氧离子相关的电场。
The oxidation of an oxycarbide of vanadium, VO0.6C0.7, and of a vanadium carbide, VC0.98, was studied athermally up to temperatures of 800° C and isothermally between 400 and 580° C at oxygen pressures ranging from 10−2to 1 atm. The oxycarbide followed the parabolic rate law below 450° C with V2O5forming as the only reaction product. The activation energy was 49 kcal/mole. VC0.98did not form an oxide in this temperature range, but rather dissolved oxygen, the activation energy being 26.6 kcal/mole. No oxygen pressure dependence on the kinetics was found for either sample in this temperature range. Both samples followed the cubic rate law during oxidation in the range of 500–580° C during which V2O5formed. There was a P1/3dependence and the activation energy was the same for both materials, 51 kcal/mole. The cubic rate law and the positive pressure dependency (rather than an anticipated negative dependency) were attributed to an electric field associated with oxygen ions chemisorbed on a thin layer of V2O5.