Abstract
Low temperature isothermal kinetic studies were performed on alkali roasting of Cr2O3 with progressive replacement of Na2CO3 in the reaction mixture by NaNO3 in the temperature range of 573 to 873 K. The influence of the nitrate on the course of the reactions was studied. Statistical design of experiments was employed to asses the relative influence of different process variables. Kinetic analysis of the experimental data shows that the reaction with NaNO3 follows a simple first-order model, and the activation energy of the reaction is 22.7 kJmol-1, as compared to 72 kJmol−1 for Na2CO3 flux.
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G. Bonnivard:Can. Inst. Min. Metall. Bull., 1967, vol. 60, pp. 1424–28.
A.A. Yousef, T.R. Boulos, G.A. Kolta, and O. Abdel Aal:J. Mines Met. Fuels, 1970, vol. 18, pp. 12–18.
J.M. Udy:Chemistry of Chromium and its compounds, Reinhold Publication, New York, NY, 1956.
M.K. Hussain, G.A. Kolta, and O. Abdel Aal:Can. Metall. Q., 1972, vol. 11, pp. 481–89.
A.K. Tripathy: Ph.D. Thesis, IIT, Bombay, 1992.
A.K. Tripathy, H.S. Ray, and P.K. Pattnayak:Trans. Inst. Min. Metall. Sect. C, 1994, vol. 103, pp. 147–51.
C. Wadier:J. Therm. Anal., 1969, vol. 1, pp. 63–74.
M.R. Udupa:Thermochem. Acta, 1976, vol. 16, pp. 231–35.
F.R. Duke and M.L. Iverson:J. Am. Chem. Soc., 1968, vol. 51, p. 5061.
V.V. Fedorov:Theory of Optimal Experiments, Academic Press, New York, NY, 1972.
D.M. Himmelblan:Process Analysis of Statistical Methods, John Wiley, New York, NY, 1970.
P. Dutta: Ph.D. Thesis, IIT, Kharagpur, 1990, chs. 3 and 4.
H.S. Ray and N. Kundu:Thermochem. Acta., 1986, vol. 101, pp. 107–18.
S.B. Sarkar, H.S. Ray, and I. Chatterjee:J. Therm. Anal., 1989, vol. 35, pp. 2467–70.
M.N. Sastri and J.O. Hill:J. Therm. Anal., 1977, vol. 11, pp. 323–26.
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Tripathy, A.K., Ray, H.S. & Pattnayak, P.K. Kinetics of roasting of chromium oxide with sodium nitrate flux. Metall Mater Trans B 26, 449–454 (1995). https://doi.org/10.1007/BF02653861
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DOI: https://doi.org/10.1007/BF02653861