Reaction kinetics of CaC2 formation from powder and compressed feeds
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The production of CaC2 from coke/lime powders and compressed powder pellets are low cost and fast processes. A number of studies have reported the reaction kinetics of these reactions but they are still not well understood and the proposed kinetic models are not comparable due to differences in the reaction conditions. Therefore the reaction behavior of CaO/C powders (0.074 mm) and cubes (5 mm × 5 mm × (4.6–5.1) mm) compressed from a mixture of powders have been studied using thermal gravimetric analysis (TGA) at 1700–1850 °C. Kinetic models were obtained from the TGA data using isoconversional and model-fitting methods. The reaction rates for the compressed feeds were lower than those for the powder feeds. This is due to the reduced surface area of the compressed samples which inhibits heat transfer from the surrounding environment (or the heating source) to the sample. The compression pressure had little influence on the reaction rate. The reaction kinetics of both the powder and the compressed feeds can be described by the contracting volume model f(α) = 3(1–α)2/3, where α is the conversion rate of reactant. The apparent activation energy and pre-exponential factor of the powder feed were estimated to 346–354 kJ∙mol–1 and 5.9 × 107 min–1, respectively, whereas those of the compressed feed were 305–327 kJ∙mol–1 and 3.6 × 106 min–1, respectively.
Keywordscalcium carbide kinetic model activation energy pre-exponential factor
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- 1.Holzrichter K, Knott A, Mertschenk B, Salzinger J. Ullmann’s Encyclopedia of Industrial Chemistry: Calcium Carbide. New York: John Wiley & Sons, Inc., 2000, 1–14Google Scholar
- 8.Mukaibo T, Yamanaka Y. Calcium carbide. III. Kinetics of the first stage of the reaction of producing calcium carbide under reduced pressure(2–3 mmHg). Journal of the Society of Chemical Industry (Japan), 1953, 56(5): 313–314Google Scholar
- 11.Torikai N, Nagaishi T, Saito S, Miyamoto G. Reaction between calcium oxide and graphite. Bulletin of the Faculty of Engineering, Yokohama National University, 1967, 16: 21–28Google Scholar
- 12.El-Naas M H. Synthesis of calcium carbide in a plasma spout fluid bed. Dissertation for the Doctoral Degree. Montreal: McGill University, 1996, 135–139Google Scholar
- 18.Müller M B. Structure, properties and reactions of CaO in burnt lime. Part 3. Composite reactions of CaO and C in solid and liquid state. Scandinavian Journal of Metallurgy, 1990, 19(5): 210–217Google Scholar
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