Vv. Akimov et As. Chernyak, EFFECT OF THE REAL STRUCTURE OF CRYSTALS ON SULFATIZATION OF TANTALONIOBATES, Journal of applied chemistry of the USSR, 65(7), 1992, pp. 1208-1215
It is shown that the thermodynamic driving force of the sulfatization
reaction depends, to a significant extent, on the depth of decompositi
on of the tantalite-columbite particles and the degree of coherence of
the interface. By computer calculations it is determined that mechani
cal activation of tantalite-columbite produces fine chemical inhomogen
eities in the near-surface layer of the activated particles caused by
elastic interaction of iron and manganese atoms with dislocations. The
formation of these inhomogeneities is the reason for the fact reveale
d earlier that it is fairly easy to selectively extract the group-A ca
tions [manganese(II) and iron(II)] from tantaloniobates with a number
of acid solutions.