Separation of Gadolinium (Gd) using Synergic Solvent Mixed Topo-D2EHPA with Extraction Method.

The main problem to obtain Gd with high purity is the similarity of chemical
properties and physical properties with the other rare earth elements (REE) such as Y and Dy, it
is necessary to do separation by the extraction process. The purpose of this research to determine
the best solvent type, amount of solvent, feed and solvent ratio in the Gd extraction process, to
determine the rate order and the value of the rate constant of Gd concentration based on
experimental data of aqueous phase concentration as a function of time and to know the effect
of temperature on the reaction speed constant. This research was conducted on variation of
solvent, amount of solvent, feed and solvent ratio in the extraction process of Gd separation,
extraction time to determine the order value and the rate constant of Gd concentration in
extraction process based on the aqueous phase concentration data as a function of time, to the
rate constant of decreasing concentration of Gd. Based on the calculation results, the solvent
composition was obtained with the best feed to separate the rare earth elements Gd in the
extraction process is 1 : 4 with 15% concentration of TOPO and 10% concentration of D2EHPA.
The separation process of Gd using extraction method by solvent TOPO-D2EHPA 2 : 1
comparison is better than single solvent D2EHPA / TOPO because of the synergistic effect. The
rate order of separation process of Gd follows order 1. The Arrhenius Gd equation becomes k =
1.46 x 10-7 exp (-6.96 kcal / mol / RT).