Naslov
Extraction and separation of Tantalum(v) with 3-Hydroxy-2-Methyl-1-(4-tolyl)-4-pyridone

Autori
Vojković, Vlasta ; Gojmerac Ivšić, Astrid ; Tamhina, Biserka

Izvornik
Croatica chemica acta (0011-1643) 70 (1997), 2; 667-677

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Sažetak
Extraction of tantalum(V) from aqueous oxalic solution with 3-hydroxy-2-methyl-1-(4-tolyl)-4-pyridone (HY) dissolved in chloroform has been examined at different acidities and ionic strengths. Tantalum(V) is quantitatively extracted with HY from oxalic solution at pH 2.3-2.5, probably as a mixed ligand Ta-oxalate-HY complex. Tantalum(V) can be quantitatively extracted even from a more acidic solution in the presence of sulphuric, hydrochloric or perchloric acids, in the acidity range from pH= 2.3 to 3.5 M H2SO4 or HCl and from pH= 2.3 to 5.5 M HClO4. Thiocyanate, perchlorate and chloride ions produce a synergistic effect on the tantalum(V) extraction with HY. In the presence of an excess of thiocyanate, perchlorate or chloride ions tantalum (V) is quantitatively extracted with HY in the acidity range from pH= 2.3 to 3.5 M H2SO4 as a mixed ligand Ta-NCS-HY, Ta-ClO4-HY or in the form Ta-Cl-HY complexes. Compositions of the complexes are studied and discussed. Tantalum(V) extraction with HY enables its separation from niobium(V), zirconium(IV) and hafnium(IV).

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA