Sorption of rare earth metals and other elements from phosphoric acid solutions

Abstract

In this study, sorption of rare earth elements (REE, lanthanum, yttrium and ytterbium), iron, aluminum and calcium from phosphoric acid solutions with the composition closeto an industrial wet process phosphoric acid, was investigated. Sorption experiments were performed both in static and dynamic conditions, using a sulfonic ion exchange resin KU-2. A few of chelating resins of the Company Hydrolite were also used: ZG D860 with macroporous azylphosphonate groups, macroporous imine diacetoxyl resin ZG D850 and macroporous thioureido chelating one ZG D840. The concentration of the components of the solutions were determined by ICP-MS on the device XSERIES 2. It was shown that the use of imine diacetoxyl chelating resin ZG D850 allows to remove calcium from the phosphoric acid solution by 88.9%. The experiments were carried out at the advisableflow rate of the solution through the adsorption column equal to 0.70 cm3/(cm2 ·min). It wasdemonstrated that the complete saturation of cation exchangerby therare earth metal (REM) cationsreached by passing 120 bed volumes of fluid, and the according degree of extraction of REM was 19.8%, further passing the solution leadedback to decreasing the degree of extraction of REE. At passing 20 bed volumes of the solution through the twocolumns with sulphonic exchanger KU-2 arranged in series, the recovery rate of the REM output from the first ion exchange column was 73.8%, using a second column increased the recovery rate by15.5%.
The data obtained demonstrates the inadvisability of using a second ion exchange column, as well as the large volumes of solutions. However, for real technology, additional technical and economic calculations are needed.