ie5023223_si_001.pdf (41.39 kB)
Model-Based Comparison of Batch and Continuous Preparative Chromatography in the Separation of Rare Earth Elements
journal contribution
posted on 2014-10-22, 00:00 authored by Niklas Andersson, Hans-Kristian Knutson, Mark Max-Hansen, Niklas Borg, Bernt NilssonThe
demand for rare earth elements (REEs) is growing, while the
future supply is uncertain. Their unique electronic characteristics
make them irreplaceable, and the commercial value of pure fractions
is high. A model-based simulation study is presented that compares
batch chromatography with the twin-column MCSGP (multicolumn countercurrent
solvent gradient purification) process for ion-exchange chromatography
of the four-component system neodymium, samarium, europium, and gadolinium.
The last three components are considered products with individual
purity requirements of 99%. The twin-column process has been shown
to be a good alternative to the batch process regarding modifier consumption
and productivity since it enables internal recycling to achieve high
purities. A new cut strategy for MCSGP is applied where subfractions
are taken from each outlet. Two multiobjective optimizations with
yield, solvent productivity, and productivity objectives show that
the MCSGP process is a better alternative than batch chromatography.