METHOD FOR CONTROLLING LANTHANIUM CONTENT IN TECHNOLOGICAL SOLUTIONS DURING HYDROMETALLURGICAL EXTRACTION OF RARE- EARTH ELEMENTS

摘要

This method finds applications in the hydrometallurgy of rare earths. It is characterized by short duration and high performance and allows carrying out a direct measurement of the lanthanum content on the process solutions in the course of the technological process. The method consists in adding the isotope Lanthanum 140 to the basic process solution at intervals, while maintaining the specific volume activity of the solution at a constant level. This is followed by measuring the activity of the process solution by gamma-spectrometry in at least two selected reference points along the process chain, one of which must coincide with the basic process solution, the activity serving as the basis for determining the lanthanum content.