Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-27T09:32:22.649Z Has data issue: false hasContentIssue false

Synthesis and Determination of Thermodynamical Properties of the Compounds of the system Ca-Mg-Bi

Published online by Cambridge University Press:  18 December 2012

C. Ramírez*
Affiliation:
ESIQIE-IPN, Z.C. 07738 Tel. 57296000 ext. 55270, México, D.F.
J. A. Romero
Affiliation:
ESIQIE-IPN, Z.C. 07738 Tel. 57296000 ext. 55270, México, D.F.
A. Hernández
Affiliation:
ESIQIE-IPN, Z.C. 07738 Tel. 57296000 ext. 55270, México, D.F.
F. Pérez
Affiliation:
University of the State of Hidalgo, Tel. 01-771-717-2000, ext. 2271, México.
Get access

Abstract

Bismuth is an element obtained as a sub-product in lead production; Mexico occupies the second position in the world in production of this element. Bismuth is used as iron, aluminum and copper alloying, in the pharmaceutical industry, in the cosmetics industry, etc. Bismuth is separated from lead by the Kroll-Betterton Process in which a Ca-Mg alloy is added to the melting lead to form the intermetallic compounds Ca3Bi2, Mg3Bi2 and Ca2MgBi2 which float to the surface of the bath. Unfortunately, there is little thermodynamical information of the compounds of the system Ca-Mg-Bi which can be used to study and optimize the Kroll-Betterton process in a theoretical way. In this work there were synthesized the compounds Ca3Bi2, Mg3Bi2 and CaMg2Bi2 using powders of pure elements (Ca, Mg and Bi) in the required amounts and melted under an inert atmosphere. After synthesis, the samples were characterized by X-Ray Diffraction to ensure the formation of the desire compounds. Later, calorimetric technique was used to determine the thermodynamical properties of the compounds. The results obtained by X-Ray Diffraction show the formation of Mg3Bi2 and Mg2CaBi2 species; however, there is no crystallographic information of the compound Ca3Bi2. The heating curves obtained by calorimetry show endothermic peaks, due to the presence of phases changes as is indicated in the Ca-Bi, Mg-Bi and Ca-Mg-Bi phases diagrams.

Keywords

Type
Articles
Copyright
Copyright © Materials Research Society 2012

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Handbook of Ternary Alloy Phase Diagrams, ASM International, (1995).Google Scholar
Massalski, T. B., “Binary Alloy Phase Diagrams”, 2nd. Edition, ASM Int, Materials Park, Oh. (1990).Google Scholar
Okamoto, H. J., “Phase Equilibria”, 13(6), 649679, (1992).CrossRefGoogle Scholar
Paliwal, M., “Thermodynamic modeling of the Mg-Bi and Mg-Sb binary systems and short-range-ordering behavior of the liquid solutions”, CALPHAD: Computer Coupling of Phase Diagrams and Thermochemistry 33, 744754, (2009).Google Scholar
Kim, H., Electrochimica Acta 60, 154162 (2012).CrossRefGoogle Scholar
Kumar, A., Advanced Materials Letters, 112, (2012).Google Scholar