Selective extraction of gold(III) in the presence of Pd(II) and Pt(IV) by salting-out of the mixture of 2-propanol and water.

The mixture of 2-propanol with water has been employed to extract Au(III) along with other precious metals such as Pd(II) and Pt(IV) by using NaCl in the concentration range of 2.5-4.0 mol dm(-3).

Spectrophotometric titration of cobalt(II) with CaCl2 in mixed solvents of 2-propanol and water for the analysis of the extraction mechanism of cobalt(II) by salting-out in the presence of CaCl2.

The spectrophotometric titration of cobalt(II) with CaCl2 was carried out in mixed solvents of 2-propanol and water at different solvent compositions of 2-propannol, water and CaCl2 to analyze the salting-out extraction mechanism of Co(II) by the addition of CaCl2 from the mixed solvents. The formation constants of betaCoCl4(2-) = [CoCl4(2-)][Co2+](-1)[Cl-](-4) in both the organic and aqueous phases were determined thorough non-linear regression of the spectrophotometric titration data by a computer program SPECFIT/32. The values of log betaCoCl4(2-) in the aqueous phases were -4.