XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 3375
Ca and 20% Mg were extracted in 8 hours. Compared to
sulfuric acid, oxalic acid proves to be a more selective and
environmentally friendly leaching agent for Li-bearing sed-
imentary claystones.
REFERENCES
1. Karrech, A., et al., A review on methods for liberating
lithium from pegmatities. Minerals Engineering, 2020.
145: p. 106085. doi: 10.1016/j.mineng.2019.106085.
2. Shan, Z., et al., Effectively promoting the crystallization
of lithium disilicate glass-ceramics by free oxygen in the
glass. Materials Chemistry and Physics, 2020. 240:
p. 122131. doi: 10.1016/j.matchemphys.2019.122131.
3. Guo, H., et al., Fundamental Research on a New Process
to Remove Al3+ as Potassium Alum during Lithium
Extraction from Lepidolite. Metallurgical and Materials
Transactions B, 2016. 47(6): p. 3557–3564. doi:
10.1007/s11663-016-0774-y.
4. Zhang, W., et al., Lithium leaching recovery and mecha-
nisms from density fractions of an Illinois Basin bitumi-
nous coal. Fuel, 2020. 268: p. 117319. doi: 10.1016/j.
fuel.2020.117319.
5. Ryu, T., et al., Recovery of lithium in seawater using a
titanium intercalated lithium manganese oxide com-
posite. Hydrometallurgy, 2019. 184: p. 22–28. doi:
10.1016/j.hydromet.2018.12.012.
6. Hu, J., et al., Perspective on powder technology for all-
solid-state batteries: How to pair sulfide electrolyte with
high-voltage cathode. Particuology, 2024. 86: p. 55–66.
doi: 10.1016/j.partic.2023.04.005.
These percentages do not seem to be suitable in terms of
the selectivity of Li in the leaching process. However, oxalic
acid had a tremendous selectivity for Li against Ca, with as
low as 5.5% maximum Ca being leached into the system.
Sulfuric acid had a lower Ca extraction compared to citric
acid and tartaric acid, with a maximum of less than 20%
leached into the system. Figure 8(c) shows the leaching effi-
ciency of Mg with the 4 different acids. The only acid that
showed selectivity of Li against Mg was oxalic acid, leach-
ing no more than 23% of Mg in the system, whereas the
other acids leached Mg to a considerable degree (more than
80% ).It can be seen that oxalic acid was an excellent acid
in both Li extraction and selectivity. Subsequent experi-
ments to test the kinetics concerning changes in the leach-
ing parameters will even make the use of this acid more
economical and overall energy efficient.
CONCLUSIONS
The use of organic acid in the leaching of Li-bearing sedi-
mentary claystone was evaluated, for both the leaching
efficiency of Li and the selectivity of Li against other impu-
rities in the clay. The characterization of the sample allowed
us to identify the main impurities and their mineral phases
which were dolomite, calcite, albite, quartz, feldspar, and
clay minerals. Knowing that specifically Mg and Ca were
very high in concentration in this sample, attention was
paid to the dissolution of these elements. Citric acid and
tartaric acid generally did not have an excellent Li extrac-
tion efficiency, and they were neither selective in the extrac-
tion of Li. Oxalic acid on the other hand extracted more
than 90% in 1 hour and 95% in 4 hours. At the same time,
oxalic acid was selective in Li extraction, as barely 5.5%
Figure 9. Speciation diagram for (a) Li in oxalic acid and b) Li in sulfuric acid, showing the ions stable complexes formed
Ca and 20% Mg were extracted in 8 hours. Compared to
sulfuric acid, oxalic acid proves to be a more selective and
environmentally friendly leaching agent for Li-bearing sed-
imentary claystones.
REFERENCES
1. Karrech, A., et al., A review on methods for liberating
lithium from pegmatities. Minerals Engineering, 2020.
145: p. 106085. doi: 10.1016/j.mineng.2019.106085.
2. Shan, Z., et al., Effectively promoting the crystallization
of lithium disilicate glass-ceramics by free oxygen in the
glass. Materials Chemistry and Physics, 2020. 240:
p. 122131. doi: 10.1016/j.matchemphys.2019.122131.
3. Guo, H., et al., Fundamental Research on a New Process
to Remove Al3+ as Potassium Alum during Lithium
Extraction from Lepidolite. Metallurgical and Materials
Transactions B, 2016. 47(6): p. 3557–3564. doi:
10.1007/s11663-016-0774-y.
4. Zhang, W., et al., Lithium leaching recovery and mecha-
nisms from density fractions of an Illinois Basin bitumi-
nous coal. Fuel, 2020. 268: p. 117319. doi: 10.1016/j.
fuel.2020.117319.
5. Ryu, T., et al., Recovery of lithium in seawater using a
titanium intercalated lithium manganese oxide com-
posite. Hydrometallurgy, 2019. 184: p. 22–28. doi:
10.1016/j.hydromet.2018.12.012.
6. Hu, J., et al., Perspective on powder technology for all-
solid-state batteries: How to pair sulfide electrolyte with
high-voltage cathode. Particuology, 2024. 86: p. 55–66.
doi: 10.1016/j.partic.2023.04.005.
These percentages do not seem to be suitable in terms of
the selectivity of Li in the leaching process. However, oxalic
acid had a tremendous selectivity for Li against Ca, with as
low as 5.5% maximum Ca being leached into the system.
Sulfuric acid had a lower Ca extraction compared to citric
acid and tartaric acid, with a maximum of less than 20%
leached into the system. Figure 8(c) shows the leaching effi-
ciency of Mg with the 4 different acids. The only acid that
showed selectivity of Li against Mg was oxalic acid, leach-
ing no more than 23% of Mg in the system, whereas the
other acids leached Mg to a considerable degree (more than
80% ).It can be seen that oxalic acid was an excellent acid
in both Li extraction and selectivity. Subsequent experi-
ments to test the kinetics concerning changes in the leach-
ing parameters will even make the use of this acid more
economical and overall energy efficient.
CONCLUSIONS
The use of organic acid in the leaching of Li-bearing sedi-
mentary claystone was evaluated, for both the leaching
efficiency of Li and the selectivity of Li against other impu-
rities in the clay. The characterization of the sample allowed
us to identify the main impurities and their mineral phases
which were dolomite, calcite, albite, quartz, feldspar, and
clay minerals. Knowing that specifically Mg and Ca were
very high in concentration in this sample, attention was
paid to the dissolution of these elements. Citric acid and
tartaric acid generally did not have an excellent Li extrac-
tion efficiency, and they were neither selective in the extrac-
tion of Li. Oxalic acid on the other hand extracted more
than 90% in 1 hour and 95% in 4 hours. At the same time,
oxalic acid was selective in Li extraction, as barely 5.5%
Figure 9. Speciation diagram for (a) Li in oxalic acid and b) Li in sulfuric acid, showing the ions stable complexes formed