Kinetic aspects of reaction between tantalum and carbon material (active carbon or graphite) under solar radiation heating

• Published in: Solar energy 2006-12, Vol.80 (12), p.1553-1560
• Main Authors: Cruz Fernandes, Jorge, Almeida Costa Oliveira, Fernando, Granier, Bernard, Badie, Jean-Marie, Rosa, Luis Guerra, Shohoji, Nobumitsu
• Format: Article
• Language: English
• Subjects: Applied sciences; Carbon; Energy; Equipments, installations and applications; Exact sciences and technology; Heating; Natural energy; Solar energy; Solar furnace; Solar thermal conversion; Tantalum mono-carbide; Tantalum sub-carbide
• ISSN: 0038-092X; 1471-1257
• DOI: 10.1016/j.solener.2006.01.001

Reaction between tantalum (Ta) and carbon (graphite or amorphous carbon) in tap-compacted powder mixture state under solar radiation heating was investigated. Although mono-carbide TaC is the final equilibrium product at 1600 °C under presence of excess carbon, formation of sub-carbide Ta 2C as the interim product was detected under certain circumstances. After 30 min reaction at 1600 °C reached by solar radiation heating, Ta powders compacted with graphite powders by pressing into pellet were fully converted to TaC but loosely tap-compacted powder mixtures of Ta and graphite yielded Ta 2C coexisted with TaC. On the other hand, Ta powders tap-compacted with amorphous carbon were fully converted to TaC under the comparable reaction condition reflecting the high reactivity and chemical carbon activity of amorphous carbon compared with those of graphite (reference state of carbon).