7
Ethaline leaching of REE from Its Ore
Figure 9 illustrates the conversion of cerium, lanthanum,
neodymium, and praseodymium in Ethaline. Similar
to Reline, the recovery of the REEs during the leaching
period remained nearly zero however, Reline showed an
increase in recovery after 6 hours, which did not occur
with Ethaline. It’s been reported that at lower pH levels,
the recovery of REEs tends to improve [28] Therefore, the
lower recovery of REEs in Ethaline can be linked to its
higher pH [19] [30].
Lactic Acid-Choline Choline Chloride leaching of REE
from Its Ore
Figure 10 illustrates the conversion of cerium, lanthanum,
neodymium, and praseodymium in lactic acid-choline chlo-
ride deep eutectic solvent (DES) leaching at 80°C. Similar to
the leaching process in Oxaline, recovery increased with lon-
ger exposure times. The recovery of the rare earth elements
(REEs) follows the same order observed in Oxaline leaching,
with cerium lanthanum neodymium praseodymium.
Recovery was selective for cerium and rose sharply from 1
hour to 8 hours. The increase in recovery did not plateau at 8
hours, suggesting that extending leaching time could further
enhance recovery. Lactic acid-choline chloride has a low pH,
which may explain the high recovery rates of the REEs, as
indicated by the results in Oxaline, which has an even lower
pH. This finding is backed by the report from [28], which
shows that lower pH levels enhance the recovery of REEs.
Glycerol-Choline Choline Chloride Leaching of REE
from Its Ore
Figure 11 illustrates the conversion of Cerium, Lanthanum,
Neodymium, and Praseodymium in Ethaline. Similar
to Reline, the recovery of the REEs remained nearly zero
throughout the leaching period. The only difference is that
the recovery of the REEs in Reline increased after 6 hours,
which was not observed in Ethaline. Since it is reported
that lower pH levels enhance the recovery of REEs [28], the
reduced recovery of REEs in Ethaline can be attributed to
its higher pH [19] [30].
0 1 2 3 4 5 6 7 8 9
0
5
10
15
20
25
30
Time/ Hours
Ce- Oxaline(80°C)
La- Oxaline(80°C)
Nd- Oxaline(80°C)
Pr- Oxaline(80°C)
Figure 8. %Recovery of Cerium, Lanthanum, Neodymium,
and Praseodymium during leaching in Oxaline DES at 80°C
0 1 2 3 4 5 6 7 8 9
0
5
10
15
20
25
30
Time/ Hours
Ce- Ethaline(80°C)
La- Ethaline(80°C)
Nd- Ethaline(80°C)
Pr- Ethaline(80°C)
Figure 9. %Recovery of Cerium, Lanthanum, Neodymium,
and Praseodymium during leaching in Ethaline DES at 80°C
0 1 2 3 4 5 6 7 8 9
0
5
10
15
20
25
30
Time/ Hours
Ce- Lactic Acid-ChCl(80°C)
La- Lactic Acid-ChCl(80°C)
Nd- Lactic Acid-ChCl(80°C)
Pr- Lactic Acid-ChCl(80°C)
Figure 10. %Recovery of Cerium, Lanthanum, Neodymium,
and Praseodymium during leaching in Lactic-Acid- Choline-
Chloride DES at 80°C
%
Recovery
%
Recovery
%
Recovery
Ethaline leaching of REE from Its Ore
Figure 9 illustrates the conversion of cerium, lanthanum,
neodymium, and praseodymium in Ethaline. Similar
to Reline, the recovery of the REEs during the leaching
period remained nearly zero however, Reline showed an
increase in recovery after 6 hours, which did not occur
with Ethaline. It’s been reported that at lower pH levels,
the recovery of REEs tends to improve [28] Therefore, the
lower recovery of REEs in Ethaline can be linked to its
higher pH [19] [30].
Lactic Acid-Choline Choline Chloride leaching of REE
from Its Ore
Figure 10 illustrates the conversion of cerium, lanthanum,
neodymium, and praseodymium in lactic acid-choline chlo-
ride deep eutectic solvent (DES) leaching at 80°C. Similar to
the leaching process in Oxaline, recovery increased with lon-
ger exposure times. The recovery of the rare earth elements
(REEs) follows the same order observed in Oxaline leaching,
with cerium lanthanum neodymium praseodymium.
Recovery was selective for cerium and rose sharply from 1
hour to 8 hours. The increase in recovery did not plateau at 8
hours, suggesting that extending leaching time could further
enhance recovery. Lactic acid-choline chloride has a low pH,
which may explain the high recovery rates of the REEs, as
indicated by the results in Oxaline, which has an even lower
pH. This finding is backed by the report from [28], which
shows that lower pH levels enhance the recovery of REEs.
Glycerol-Choline Choline Chloride Leaching of REE
from Its Ore
Figure 11 illustrates the conversion of Cerium, Lanthanum,
Neodymium, and Praseodymium in Ethaline. Similar
to Reline, the recovery of the REEs remained nearly zero
throughout the leaching period. The only difference is that
the recovery of the REEs in Reline increased after 6 hours,
which was not observed in Ethaline. Since it is reported
that lower pH levels enhance the recovery of REEs [28], the
reduced recovery of REEs in Ethaline can be attributed to
its higher pH [19] [30].
0 1 2 3 4 5 6 7 8 9
0
5
10
15
20
25
30
Time/ Hours
Ce- Oxaline(80°C)
La- Oxaline(80°C)
Nd- Oxaline(80°C)
Pr- Oxaline(80°C)
Figure 8. %Recovery of Cerium, Lanthanum, Neodymium,
and Praseodymium during leaching in Oxaline DES at 80°C
0 1 2 3 4 5 6 7 8 9
0
5
10
15
20
25
30
Time/ Hours
Ce- Ethaline(80°C)
La- Ethaline(80°C)
Nd- Ethaline(80°C)
Pr- Ethaline(80°C)
Figure 9. %Recovery of Cerium, Lanthanum, Neodymium,
and Praseodymium during leaching in Ethaline DES at 80°C
0 1 2 3 4 5 6 7 8 9
0
5
10
15
20
25
30
Time/ Hours
Ce- Lactic Acid-ChCl(80°C)
La- Lactic Acid-ChCl(80°C)
Nd- Lactic Acid-ChCl(80°C)
Pr- Lactic Acid-ChCl(80°C)
Figure 10. %Recovery of Cerium, Lanthanum, Neodymium,
and Praseodymium during leaching in Lactic-Acid- Choline-
Chloride DES at 80°C
%
Recovery
%
Recovery
%
Recovery