Study of co-crystallization of neodymium and strontium sulphates in the absence of potassium ions

Abstract

The processes of co-crystallization of neodymium and strontium sulfates have been studied using X-ray phase, X-ray spectral analyses and microscopy. For the first time, high absorption activity of crystal matrices of trigonal modification SrSO4 · 0.5H2O and its dehydrated monoclinic modification SrSO4 to isomorphic heterovalent inclusion of Nd3+ ions with the formation of moisture-resistant solid solutions were established. The parameters of the elementary cells of solid solutions and their structural proximity are determined. In a humid environment, solid solutions decompose within 6–10 hours to form stable poorly soluble individual compounds Nd2(SO4)3 · 8H2O and rhombic modification SrSO4.