INDUSTRIAL precipitation of cUPRIC HydroxY-salts
Andrej Lubej,a
Tine Koloini,b and Ciril Poharb
a Cinkarna
Celje, Metallurgical and Chemical Company, Kidričeva 26, SI-3000 Celje, Slovenia,
b Faculty of Chemistry and Chemical Technology, University of
Ljubljana, Aškerčeva 5 SI-1000 Ljubljana, Slovenia
Abstract
The reaction between Cu2Cl(OH)3 and slaked
lime suspension was studied. It was found that the concentrations of the
participating ions in the reaction mixture determined which of the possible
products CuO, or CaCu3Cl2(OH)6, or CaCu4Cl2(OH)8
was precipitated. The reaction conditions also influenced the repose times of
the precipitates. The considerably longer repose time of CuO than that of the
MB4 enables industrial production of the MB4 of the prescribed purity. When co-precipitation
of MB4 and CuO occurs, it causes blackening of the product. From the composition
and the concentrations of all the ionic species present in equilibrium with the
solid phase, the solubility products of the precipitated compounds were
estimated.
Key words: Copper fungicides, copper oxide, calcium tri-copper di-chloride hexa-hydroxide, calcium tetra-copper di-chloride octa-hydroxide, solubility constant, industrial precipitation.