Experimental Chevreul’s Salt Production Methods on Copper Recovery

Experimental production methods of Chevreul’s salt
being an intermediate stage product in copper recovery were
investigated on this article. Chevreul’s salt, Cu2SO3.CuSO3.2H2O,
being a mixed valence copper sulphite compound, has been obtained
by using different methods and reagents. Chevreul’s salt has an
intense brick-red color. It is highly stable and expensive. The
production of Chevreul’s salt plays a key role in hydrometallurgy.
Thermodynamic tendency on precipitation of Chevreul’s salt is
related to pH and temperature. Besides, SO2 gaseous is a versatile
reagent for precipitating of copper sulphites, Using of SO2 for
selective precipitation can be made by appropriate adjustments of pH
and temperature. Chevreul’s salt does not form in acidic solutions if
those solutions contains considerable amount of sulfurous acid. It is
necessary to maintain between pH 2–4.5, because, solubility of
Chevreul’s salt increases with decreasing of pH values. Also, the
region which Chevreul’s salt is stable can be seen from the potentialpH
diagram.

• Turan Çalban
• Oral Laçin
• Abdüsselam Kurtbas

• Chevreul’s salt
• copper recovery
• copper sulphite
• stage product.

[1] T. Çalban, S. Çolak and M. Yesilyurt, “Statistical modelling of
Chevreul’s salt recovery from leach solutions containing copper”, Chem.
Eng. Process., vol. 45, 2006, pp. 168-174.
[2] J.B. de Andrade, L.A. da Silva, “Isomorphic series of double sulfites of
the Cu2SO3.MSO3·2H2O (M= Cu, Fe, Mn, and Cd) type,” J. Braz. Chem.
Sci., vol. 15, 2004, pp. 170-177.
[3] M. Inoue, H. Grijalva, M.B. Inoue, Q. Fernando, “Spectroscopic and
magnetic properties of Chevreul’s salt, a mixed valence copper sulfite
Cu3(SO3)2.2H2O”, Inorgan. Chim. Acta, vol. 295, 1999, pp. 125-127.
[4] A.J. Parker, D.M. Muir, “Recovery of copper powder from copper
concentrates and from solutions of copper (II) sulfates using sulfur
dioxide and aqueous acetonitrile”, Hydrometallurgy vol. 6, 1981, pp.
239-260.
[5] L.A. Silva, J.R. Matos, J.B. de Andrade, “Synthesis, identification and
thermal decomposition of double sulfites like Cu2SO3.MSO3.2H2O (M =
Cu, Fe, Mn or Cd)”, Thermochimica Acta, 360, 17 (2000).
[6] S. Çolak, T. Çalban, M. Yesilyurt, D. Sergili, Z. Ekinci, “Recovery of
copper powders from leach solutions containing copper by means of
ammonia, sulphur dioxide and acetonitrile”, Powder Technology, vol.
134, 2003, pp. 65-71.
[7] M. Yesilyurt, T. Çalban, “Precipitation of Chevreul’s Salt from CuSO4
Solutions with Na2SO3”, Chemical and Process Engineering, vol. 28,
2007, pp. 85-91.
[8] T. Çalban, S. Kuslu, S. Çolak, “Precipitation Conditions of Chevreul’s
Salt from Syntetic Aqueous CuSO4 Solutions”, Chemical Engineering
Communications, vol. 196, 2009, pp. 1018-1029.
[9] T. Çalban, B. Kaynarca, F. Sevim, H. Eroğlu, “Precipitation Conditions
of Chevreul's Salt Using (NH4)2SO3 from Synthetic Aqueous CuSO4
Solutions”, Asian Journal of Chemistry, vo.. 26 (18), 2014, pp. 6111-
6117.
[10] P. Kierkegaard, B. Nyberg, “The crystal structure of
Cu2SO3.CuSO3.2H2O”, Acta Chem. Scand., vol. 19, 1965, p. 2189.