1660 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
leaching time. Therefore, the optimal leaching time for Sc
recovery using TABWL is one hour [22].
CONCLUSION
Sc recovery from RM by H2SO4 ABWL is limited due to
the inability of acid penetration through the sulfated prod-
uct layer during the baking stage. SEM-EDS analysis of the
acid-baked RM shows that a shell of sulfated Fe surrounds
a core of unreacted Fe. Surface area analysis of the baked
samples after the first and the second stages showed that
there was a marked increase in the pore surface area of RM
after the first leach. It is concluded that TABWL improved
access to the Sc in the bulk of the RM by washing the sul-
fated species, thereby exposing a new surface while using
the same amount of acid as in the case of ABWL at a similar
temperature. Over 75% Sc can be recovered by TABWL at
200°C for one hour using 1 ml H2SO4/g RM and leaching
at 75°C for one hour with an S/L =1/10. Detailed optimi-
zation of RM’s TABWL is currently underway.
REFERENCES
[1] A.B.B. Junior, D.C.R. Espinosa, J. Vaughan, and
J.A.S. Tenório, “Recovery of scandium from vari-
ous sources: A critical review of the state of the art
and future prospects,” Minerals Engineering, vol.
172, p. 107148, 2021/10/01/ 2021, doi: 10.1016
/j.mineng.2021.107148.
[2] A.D. Salman et al., “Scandium Recovery Methods
from Mining, Metallurgical Extractive Industries, and
Industrial Wastes,” (in eng), Materials (Basel), vol. 15,
no. 7, Mar 23 2022, doi: 10.3390/ma15072376.
[3] J. Demol, E. Ho, K. Soldenhoff, and G. Senanayake,
“The sulfuric acid bake and leach route for process-
ing of rare earth ores and concentrates: A review,”
Hydrometallurgy, vol. 188, pp. 123–139, 2019/09/01/
2019, doi: 10.1016/j.hydromet.2019.05.015.
[4] Z. Hu and S. Gao, “Upper crustal abundances of
trace elements: A revision and update,” Chemical
Geology, vol. 253, no. 3, pp. 205–221, 2008/08/15/
2008, doi: 10.1016/j.chemgeo.2008.05.010.
[5] N. Krishnamurthy, “Extractive metallurgy of rare
earths,” C.K. Gupta, Ed., Second edition. ed, 2016.
[6] W. Wang, Y. Pranolo, and C.Y. Cheng, “Metallurgical
processes for scandium recovery from various
resources: A review,” Hydrometallurgy, vol. 108, no.
1, pp. 100–108, 2011/06/01/ 2011, doi: 10.1016
/j.hydromet.2011.03.001.
[7] X. Shaoquan and L. Suqing, “Review of the
extractive metallurgy of scandium in China
(1978–1991),” Hydrometallurgy, vol. 42, no.
3, pp. 337–343, 1996/10/01/ 1996, doi:
10.1016/0304-386X(95)00086-V.
[8] J. Kim and G. Azimi, “An innovative process for
extracting scandium from nickeliferous laterite ore:
Carbothermic reduction followed by NaOH cracking,”
Hydrometallurgy, vol. 191, p. 105194, 2020/01/01/
2020, doi: 10.1016/j.hydromet.2019.105194.
[9] L. Wang, P. Wang, W.-Q. Chen, Q.-Q. Wang, and
H.-S. Lu, “Environmental impacts of scandium
oxide production from rare earths tailings of Bayan
Obo Mine,” Journal of Cleaner Production, vol.
270, p. 122464, 2020/10/10/ 2020, doi: 10.1016
/j.jclepro.2020.122464.
[10] B. Zhang, X. Xue, X. Huang, H. Yang, and J. Han,
“Study on Leaching Valuable Elements from Bayan
Obo Tailings,” Cham, 2017: Springer International
Publishing, in Proceedings of the 3rd Pan American
Materials Congress, pp. 633–641.
[11] B. Zhang, X.X. Xue, X.W. Huang, H. Yang, and G.J.
Chen, “Study on recycling and leaching valuable
elements from Bayan Obo tailings,” Metallurgical
Research &Technology, vol. 116, no. 1, Jan 2019, Art
no. 114, doi: 10.1051/metal/2018040.
[12] W. Ding et al., “Extraction of Scandium and Iron from
Red Mud,” Mineral Processing and Extractive Metallurgy
Review, vol. 43, no. 1, pp. 61–68, 2020/01/02 2020,
doi: 10.1080/08827508.2020.1833195.
[13] C.R. Borra, Y. Pontikes, K. Binnemans, and T.
Van Gerven, “Leaching of rare earths from baux-
ite residue (red mud),” Minerals Engineering, vol.
76, pp. 20–27, 2015/05/15/ 2015, doi: 10.1016
/j.mineng.2015.01.005.
[14] R.M. Rivera, B. Ulenaers, G. Ounoughene, K.
Binnemans, and T. Van Gerven, “Extraction of
rare earths from bauxite residue (red mud) by dry
digestion followed by water leaching,” Minerals
Engineering, vol. 119, pp. 82–92, 2018/04/01/ 2018,
doi: 10.1016/j.mineng.2018.01.023.
[15] R.P. Narayanan, N.K. Kazantzis, and M.H. Emmert,
“Selective Process Steps for the Recovery of Scandium
from Jamaican Bauxite Residue (Red Mud),” ACS
Sustainable Chemistry &Engineering, vol. 6, no. 1,
pp. 1478–1488, 2018/01/02 2018, doi: 10.1021
/acssuschemeng.7b03968.
[16] C.R. Borra, B. Blanpain, Y. Pontikes, K. Binnemans,
and T. Van Gerven, “Recovery of Rare Earths and
Other Valuable Metals From Bauxite Residue (Red
Mud): A Review,” Journal of Sustainable Metallurgy,
vol. 2, no. 4, pp. 365–386, 2016/12/01 2016, doi:
10.1007/s40831-016-0068-2.
leaching time. Therefore, the optimal leaching time for Sc
recovery using TABWL is one hour [22].
CONCLUSION
Sc recovery from RM by H2SO4 ABWL is limited due to
the inability of acid penetration through the sulfated prod-
uct layer during the baking stage. SEM-EDS analysis of the
acid-baked RM shows that a shell of sulfated Fe surrounds
a core of unreacted Fe. Surface area analysis of the baked
samples after the first and the second stages showed that
there was a marked increase in the pore surface area of RM
after the first leach. It is concluded that TABWL improved
access to the Sc in the bulk of the RM by washing the sul-
fated species, thereby exposing a new surface while using
the same amount of acid as in the case of ABWL at a similar
temperature. Over 75% Sc can be recovered by TABWL at
200°C for one hour using 1 ml H2SO4/g RM and leaching
at 75°C for one hour with an S/L =1/10. Detailed optimi-
zation of RM’s TABWL is currently underway.
REFERENCES
[1] A.B.B. Junior, D.C.R. Espinosa, J. Vaughan, and
J.A.S. Tenório, “Recovery of scandium from vari-
ous sources: A critical review of the state of the art
and future prospects,” Minerals Engineering, vol.
172, p. 107148, 2021/10/01/ 2021, doi: 10.1016
/j.mineng.2021.107148.
[2] A.D. Salman et al., “Scandium Recovery Methods
from Mining, Metallurgical Extractive Industries, and
Industrial Wastes,” (in eng), Materials (Basel), vol. 15,
no. 7, Mar 23 2022, doi: 10.3390/ma15072376.
[3] J. Demol, E. Ho, K. Soldenhoff, and G. Senanayake,
“The sulfuric acid bake and leach route for process-
ing of rare earth ores and concentrates: A review,”
Hydrometallurgy, vol. 188, pp. 123–139, 2019/09/01/
2019, doi: 10.1016/j.hydromet.2019.05.015.
[4] Z. Hu and S. Gao, “Upper crustal abundances of
trace elements: A revision and update,” Chemical
Geology, vol. 253, no. 3, pp. 205–221, 2008/08/15/
2008, doi: 10.1016/j.chemgeo.2008.05.010.
[5] N. Krishnamurthy, “Extractive metallurgy of rare
earths,” C.K. Gupta, Ed., Second edition. ed, 2016.
[6] W. Wang, Y. Pranolo, and C.Y. Cheng, “Metallurgical
processes for scandium recovery from various
resources: A review,” Hydrometallurgy, vol. 108, no.
1, pp. 100–108, 2011/06/01/ 2011, doi: 10.1016
/j.hydromet.2011.03.001.
[7] X. Shaoquan and L. Suqing, “Review of the
extractive metallurgy of scandium in China
(1978–1991),” Hydrometallurgy, vol. 42, no.
3, pp. 337–343, 1996/10/01/ 1996, doi:
10.1016/0304-386X(95)00086-V.
[8] J. Kim and G. Azimi, “An innovative process for
extracting scandium from nickeliferous laterite ore:
Carbothermic reduction followed by NaOH cracking,”
Hydrometallurgy, vol. 191, p. 105194, 2020/01/01/
2020, doi: 10.1016/j.hydromet.2019.105194.
[9] L. Wang, P. Wang, W.-Q. Chen, Q.-Q. Wang, and
H.-S. Lu, “Environmental impacts of scandium
oxide production from rare earths tailings of Bayan
Obo Mine,” Journal of Cleaner Production, vol.
270, p. 122464, 2020/10/10/ 2020, doi: 10.1016
/j.jclepro.2020.122464.
[10] B. Zhang, X. Xue, X. Huang, H. Yang, and J. Han,
“Study on Leaching Valuable Elements from Bayan
Obo Tailings,” Cham, 2017: Springer International
Publishing, in Proceedings of the 3rd Pan American
Materials Congress, pp. 633–641.
[11] B. Zhang, X.X. Xue, X.W. Huang, H. Yang, and G.J.
Chen, “Study on recycling and leaching valuable
elements from Bayan Obo tailings,” Metallurgical
Research &Technology, vol. 116, no. 1, Jan 2019, Art
no. 114, doi: 10.1051/metal/2018040.
[12] W. Ding et al., “Extraction of Scandium and Iron from
Red Mud,” Mineral Processing and Extractive Metallurgy
Review, vol. 43, no. 1, pp. 61–68, 2020/01/02 2020,
doi: 10.1080/08827508.2020.1833195.
[13] C.R. Borra, Y. Pontikes, K. Binnemans, and T.
Van Gerven, “Leaching of rare earths from baux-
ite residue (red mud),” Minerals Engineering, vol.
76, pp. 20–27, 2015/05/15/ 2015, doi: 10.1016
/j.mineng.2015.01.005.
[14] R.M. Rivera, B. Ulenaers, G. Ounoughene, K.
Binnemans, and T. Van Gerven, “Extraction of
rare earths from bauxite residue (red mud) by dry
digestion followed by water leaching,” Minerals
Engineering, vol. 119, pp. 82–92, 2018/04/01/ 2018,
doi: 10.1016/j.mineng.2018.01.023.
[15] R.P. Narayanan, N.K. Kazantzis, and M.H. Emmert,
“Selective Process Steps for the Recovery of Scandium
from Jamaican Bauxite Residue (Red Mud),” ACS
Sustainable Chemistry &Engineering, vol. 6, no. 1,
pp. 1478–1488, 2018/01/02 2018, doi: 10.1021
/acssuschemeng.7b03968.
[16] C.R. Borra, B. Blanpain, Y. Pontikes, K. Binnemans,
and T. Van Gerven, “Recovery of Rare Earths and
Other Valuable Metals From Bauxite Residue (Red
Mud): A Review,” Journal of Sustainable Metallurgy,
vol. 2, no. 4, pp. 365–386, 2016/12/01 2016, doi:
10.1007/s40831-016-0068-2.