XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 1711
REFERENCES
Aleksenko, S.S., Gumenyuk, A.P., &Mushtakova, S.P.
(2002). Study of the speciation of rhodium (III) in a
hydrochloric acid solution by capillary electrophore-
sis. Journal of Analytical Chemistry, 57, 215–220. doi:
10.1023/A:1014488114371.
Asamoah-Bekoe, Y. (1998). Investigation of the leaching of
the platinum group metal concentrate in hydrochloric acid
solution by chlorine. (Master’s thesis, University of the
Witwatersrand, Johannesburg). Retrieved from wired
space.wits.ac.za/handle/10539/21348.
Bernardis, F.L., Grant, R.A., &Sherrington, D.C. (2005).
A review of methods of separation of the platinum-
group metals through their chloro-complexes. Reactive
&Functional Polymers, 65, 205–217. doi: 10.1016
/j.reactfunctpolym.2005.05.011.
Chagnes, A. (2020). Simulation of solvent extrac-
tion flowsheets by a global model combining
physicochemical and engineering approaches—appli-
cation to cobalt (II) extraction by D2EHPA. sol-
vent extraction and ion exchange, 38(1), 3–13. doi:
10.1080/07366299.2019.1691135.
Crundwell, F.K., Moats, M.S., Ramachandran, V.,
Robinson, T.G., &Davenport, W.G. (2011).Refining
of the Platinum-Group Metals. Extractive Metallurgy of
Nickel, Cobalt, and Platinum-Group Metals, (pp.489–
534). Retrieved from https://app.knovel.com/hot-
link/toc/id:kpEMNCPGMO/extractive-metallurgy/
extractive-metallurgy.
Crundwell, F. (2019). Platinum Group Metals. In R.C.
Dunne, S.K. Kawatra., &C.A Young. SME Mineral
Processing &Extractive Metallurgy Handbook, (pp.1995–
2012). Retrieved from https://app.knovel.com/hotlink
/toc/id:kpSMEMPE1/sme-mineral-processing
/sme-mineral-processing.
Ding, Y., Zheng, H., Zhang, S., Liu, B., Wu, B., &
Jian, Z. (2020). Highly efficient recovery of plati-
num, palladium, and rhodium from spent automo-
tive catalysts via iron melting collection. Resources,
Conservation &Recycling 155, 104644. doi: 10.1016
/j.resconrec.2019.104644.
Firmansyah, M.L., Kubota, F., Yoshida, W., &Goto, M.
(2019). Application of a novel phosphonium-based
ionic liquid to the separation of platinum group met-
als from automobile catalyst leach liquor. Industrial &
Engineering Chemistry Research, 58(9), 3845–3852.
doi: 10.1021/acs.iecr.8b05848.
Gaita, R., &Al-Bazi, S.J. (1995). An Ion Exchange Method
for Selective Separation of Platinum, Palladium
and Rhodium from Solutions obtained by leaching
Automotive Catalytic Converters. Talanta,42 (2),
249–255. doi: 10.1016/0039-9140(94)00246-0.
Galvão, T.L., Kuznetsova, A., Gomes, J.R.,
Zheludkevich, M.L., Tedim, J., &Ferreira, M.G.
(2016). A computational UV–Vis spectroscopic study
of the chemical speciation of 2-mercaptobenzothiazole
corrosion inhibitor in aqueous solution. Theoretical
Chemistry Accounts, 135, 1–11. doi: 10.1007
/s00214-016-1839-3.
Ge, T., He, J.-D., Xu, L., Xiong, Y.-H., Wang, L.,
Zhou, X.-W., Tian, Y.-P., &Zhao, Z. (2023). Recovery
of platinum from spent automotive catalyst based on
hydrometallurgy. Rare Metals, 42(4), 1118–1137. doi:
10.1007/s12598-022-02236-2.
Ghaedi, M., Shokrollahi, A., Niknam, K., Niknam, E.,
Najibi, A., &Soylak, M. (2009). Cloud point extrac-
tion and flame atomic absorption spectrometric
determination of cadmium (II), lead (II), palladium
(II) and silver (I) in environmental samples. Journal
of Hazardous Materials, 168(2–3), 1022–1027. doi:
10.1016/j.jhazmat.2009.02.130.
Goc, K., Kluczka, J., Benke, G., Malarz, J., Pianowska, K.,
&Leszczyńska-Sejda, K. (2021). Application of
ion exchange for recovery of noble metals. Minerals,
11(11), 1188. doi: 10.3390/min11111188.
Han, Q., Huo, Y., Wu, J., He, Y., Yang, X., &Yang, L.
(2017). Determination of ultra-trace rhodium in
water samples by graphite furnace atomic absorp-
tion spectrometry after cloud point extraction using
2-(5-iodo-2-pyridylazo)-5-dimethylaminoaniline as a
chelating agent. Molecules, 22(4), 487. doi: 10.3390/
molecules22040487.
Hong, H.J., Yub, H., Hong, S., Hwang, J.Y., Kimb, S.M.,
Park, M.S., &Jeong, H.S. (2020). Modified tunicate
nanocellulose liquid crystalline fiber as closed loop
for recycling platinum-group metals. Carbohydrate
Polymers, 228 (115424), 1–7. doi: 10.1016
/j.carbpol.2019.115424.
Johnson Matthey. (2020). Pgm Market Report February.
Retrieved from http://www.platinum.matthey.com
/services/market-research/pgm-market-reports.
Johnson Matthey. (2023). Pgm Market Report May.
Retrieved from https://matthey.com/en/products
-and-markets/pgms-and-circularity/pgmmarkets
/pgm-market-reports.

Previous Page Next Page

Extracted Text (may have errors)

XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 1711
REFERENCES
Aleksenko, S.S., Gumenyuk, A.P., &Mushtakova, S.P.
(2002). Study of the speciation of rhodium (III) in a
hydrochloric acid solution by capillary electrophore-
sis. Journal of Analytical Chemistry, 57, 215–220. doi:
10.1023/A:1014488114371.
Asamoah-Bekoe, Y. (1998). Investigation of the leaching of
the platinum group metal concentrate in hydrochloric acid
solution by chlorine. (Master’s thesis, University of the
Witwatersrand, Johannesburg). Retrieved from wired
space.wits.ac.za/handle/10539/21348.
Bernardis, F.L., Grant, R.A., &Sherrington, D.C. (2005).
A review of methods of separation of the platinum-
group metals through their chloro-complexes. Reactive
&Functional Polymers, 65, 205–217. doi: 10.1016
/j.reactfunctpolym.2005.05.011.
Chagnes, A. (2020). Simulation of solvent extrac-
tion flowsheets by a global model combining
physicochemical and engineering approaches—appli-
cation to cobalt (II) extraction by D2EHPA. sol-
vent extraction and ion exchange, 38(1), 3–13. doi:
10.1080/07366299.2019.1691135.
Crundwell, F.K., Moats, M.S., Ramachandran, V.,
Robinson, T.G., &Davenport, W.G. (2011).Refining
of the Platinum-Group Metals. Extractive Metallurgy of
Nickel, Cobalt, and Platinum-Group Metals, (pp.489–
534). Retrieved from https://app.knovel.com/hot-
link/toc/id:kpEMNCPGMO/extractive-metallurgy/
extractive-metallurgy.
Crundwell, F. (2019). Platinum Group Metals. In R.C.
Dunne, S.K. Kawatra., &C.A Young. SME Mineral
Processing &Extractive Metallurgy Handbook, (pp.1995–
2012). Retrieved from https://app.knovel.com/hotlink
/toc/id:kpSMEMPE1/sme-mineral-processing
/sme-mineral-processing.
Ding, Y., Zheng, H., Zhang, S., Liu, B., Wu, B., &
Jian, Z. (2020). Highly efficient recovery of plati-
num, palladium, and rhodium from spent automo-
tive catalysts via iron melting collection. Resources,
Conservation &Recycling 155, 104644. doi: 10.1016
/j.resconrec.2019.104644.
Firmansyah, M.L., Kubota, F., Yoshida, W., &Goto, M.
(2019). Application of a novel phosphonium-based
ionic liquid to the separation of platinum group met-
als from automobile catalyst leach liquor. Industrial &
Engineering Chemistry Research, 58(9), 3845–3852.
doi: 10.1021/acs.iecr.8b05848.
Gaita, R., &Al-Bazi, S.J. (1995). An Ion Exchange Method
for Selective Separation of Platinum, Palladium
and Rhodium from Solutions obtained by leaching
Automotive Catalytic Converters. Talanta,42 (2),
249–255. doi: 10.1016/0039-9140(94)00246-0.
Galvão, T.L., Kuznetsova, A., Gomes, J.R.,
Zheludkevich, M.L., Tedim, J., &Ferreira, M.G.
(2016). A computational UV–Vis spectroscopic study
of the chemical speciation of 2-mercaptobenzothiazole
corrosion inhibitor in aqueous solution. Theoretical
Chemistry Accounts, 135, 1–11. doi: 10.1007
/s00214-016-1839-3.
Ge, T., He, J.-D., Xu, L., Xiong, Y.-H., Wang, L.,
Zhou, X.-W., Tian, Y.-P., &Zhao, Z. (2023). Recovery
of platinum from spent automotive catalyst based on
hydrometallurgy. Rare Metals, 42(4), 1118–1137. doi:
10.1007/s12598-022-02236-2.
Ghaedi, M., Shokrollahi, A., Niknam, K., Niknam, E.,
Najibi, A., &Soylak, M. (2009). Cloud point extrac-
tion and flame atomic absorption spectrometric
determination of cadmium (II), lead (II), palladium
(II) and silver (I) in environmental samples. Journal
of Hazardous Materials, 168(2–3), 1022–1027. doi:
10.1016/j.jhazmat.2009.02.130.
Goc, K., Kluczka, J., Benke, G., Malarz, J., Pianowska, K.,
&Leszczyńska-Sejda, K. (2021). Application of
ion exchange for recovery of noble metals. Minerals,
11(11), 1188. doi: 10.3390/min11111188.
Han, Q., Huo, Y., Wu, J., He, Y., Yang, X., &Yang, L.
(2017). Determination of ultra-trace rhodium in
water samples by graphite furnace atomic absorp-
tion spectrometry after cloud point extraction using
2-(5-iodo-2-pyridylazo)-5-dimethylaminoaniline as a
chelating agent. Molecules, 22(4), 487. doi: 10.3390/
molecules22040487.
Hong, H.J., Yub, H., Hong, S., Hwang, J.Y., Kimb, S.M.,
Park, M.S., &Jeong, H.S. (2020). Modified tunicate
nanocellulose liquid crystalline fiber as closed loop
for recycling platinum-group metals. Carbohydrate
Polymers, 228 (115424), 1–7. doi: 10.1016
/j.carbpol.2019.115424.
Johnson Matthey. (2020). Pgm Market Report February.
Retrieved from http://www.platinum.matthey.com
/services/market-research/pgm-market-reports.
Johnson Matthey. (2023). Pgm Market Report May.
Retrieved from https://matthey.com/en/products
-and-markets/pgms-and-circularity/pgmmarkets
/pgm-market-reports.

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1710 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
mentioned in the previous section, which have slow ligand
exchange kinetics. These characteristics lead to low Pt and
Rh extractions in the initial stages of the reaction. The
competition for adsorption sites, potentially arising from
chloride ions released after Pd (II) adsorption and [FeCl4]–,
as indicated in Table 2, could result in the delayed adsorp-
tion of Pt (IV) and Rh (III). Among the two kinetically
inert PGMs, Rh (III) is more inert, with more water
and hydroxyl ligands, making its extraction much slower
(Bernardis, Grant, and Sherrington 2005 Shelimov et al.,
2000).
In Figure 4, at 115 minutes, Pd (II) extraction exceeded
98%, while Pt ((IV) extraction was at 76%, and Rh (III)
extraction was less than 1%. The increase in Pt extrac-
tion could be attributed to the formation of more extract-
able anionic species from the chloride ions released by Pd
adsorption. Notably, the extraction of Rh (III) increased
after 24 hours of incubation time to 37%, and since Rh has
more aqua chloro species, a longer time is required for the
unreactive ligands to be replaced to form more extractable
species, extending up to 7 days (Kononova et al., 2010).
Concentration Factors for CPE and IX, and CPE’s
Potential Integration in PGMs Refineries
At 10% concentration of the activating agent, CPE had
a total PGMs concentration factor of 14.10 and 15.21 at
pH 1.00 and pH 4.00–5.75 respectively compared to total
PGMs concentration factors of 13.40 and 15.92 at 20%
tin (II) chloride di-hydrate at similar pH values respec-
tively. IX had a concentration factor of 8.04. The higher
CPE concentration factor indicates a potential of a smaller
processing plant for PGMs recovery, which would result in
lower capital costs, compared to IX.
Current commercial PGMs recovery processes have Pd
and Pt raffinates ranging from 100–600 ppm (Crundwell
et al., 2011). Treatment involves boiling down to attain
solution concentration before reprocessing raising refinery
costs. The CPE results in this study suggest its potential
integration in PGM refineries to lower process costs.
CONCLUSIONS AND FURTHER
RECOMMENDATIONS
This study aimed to compare the efficiency of extracting Pt,
Pd, and Rh from a spent autocatalytic converter chloride
leach solution using Cloud Point Extraction (CPE) and
Ion Exchange (IX). CPE demonstrated optimal selectivity
at low pH and achieved high extractions under near-neutral
pH in a single step. In contrast, the impact of pH on IX was
minimal. Both processes exhibited low selectivity for indi-
vidual PGMs, with CPE at 10% tin (II) chloride showing
the best selectivity, but Pt and Pd recovery was only 50%
at pH 1, and Rh was not extracted. Increasing the reducing
agent in CPE to 20% improved Rh extraction but activated
the recovery of Al, Fe, and Mg.
IX required a shorter incubation time for Pd and Pt
extraction compared to CPE, but it needed 24 hours for
37% Rh extraction, while CPE at 20% tin (II) chloride
achieved 40% extraction in 115 minutes. While these find-
ings suggest the feasibility of CPE for SACs leach metal
concentrations, further comprehensive investigations are
necessary for a robust comparison with existing PGM
extraction methods.
Further work requires exploring the effect of pH on
PGMs and impurity metal extraction in the pH range of
7–14. It is also recommended to extend CPE application to
low-concentration solutions like PGM industry process raf-
finates and waste streams. In addition, research on the recy-
clability of the surfactant phase and impurity scrubbing is
essential. To validate CPE’s commercial potential, piloting,
cost-benefit analyses, and process costing for comparison
with established technologies like solvent extraction is also
recommended.
ACKNOWLEDGMENTS
The authors would like to thank the Department of
Science and Innovation (DSI) and the National Research
Foundation (NRF) for funding under SARChI grant num-
ber 98350.
Figure 4. Effect of contact time on PGMs extraction by IX

Previous Page Next Page

Extracted Text (may have errors)

1710 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
mentioned in the previous section, which have slow ligand
exchange kinetics. These characteristics lead to low Pt and
Rh extractions in the initial stages of the reaction. The
competition for adsorption sites, potentially arising from
chloride ions released after Pd (II) adsorption and [FeCl4]–,
as indicated in Table 2, could result in the delayed adsorp-
tion of Pt (IV) and Rh (III). Among the two kinetically
inert PGMs, Rh (III) is more inert, with more water
and hydroxyl ligands, making its extraction much slower
(Bernardis, Grant, and Sherrington 2005 Shelimov et al.,
2000).
In Figure 4, at 115 minutes, Pd (II) extraction exceeded
98%, while Pt ((IV) extraction was at 76%, and Rh (III)
extraction was less than 1%. The increase in Pt extrac-
tion could be attributed to the formation of more extract-
able anionic species from the chloride ions released by Pd
adsorption. Notably, the extraction of Rh (III) increased
after 24 hours of incubation time to 37%, and since Rh has
more aqua chloro species, a longer time is required for the
unreactive ligands to be replaced to form more extractable
species, extending up to 7 days (Kononova et al., 2010).
Concentration Factors for CPE and IX, and CPE’s
Potential Integration in PGMs Refineries
At 10% concentration of the activating agent, CPE had
a total PGMs concentration factor of 14.10 and 15.21 at
pH 1.00 and pH 4.00–5.75 respectively compared to total
PGMs concentration factors of 13.40 and 15.92 at 20%
tin (II) chloride di-hydrate at similar pH values respec-
tively. IX had a concentration factor of 8.04. The higher
CPE concentration factor indicates a potential of a smaller
processing plant for PGMs recovery, which would result in
lower capital costs, compared to IX.
Current commercial PGMs recovery processes have Pd
and Pt raffinates ranging from 100–600 ppm (Crundwell
et al., 2011). Treatment involves boiling down to attain
solution concentration before reprocessing raising refinery
costs. The CPE results in this study suggest its potential
integration in PGM refineries to lower process costs.
CONCLUSIONS AND FURTHER
RECOMMENDATIONS
This study aimed to compare the efficiency of extracting Pt,
Pd, and Rh from a spent autocatalytic converter chloride
leach solution using Cloud Point Extraction (CPE) and
Ion Exchange (IX). CPE demonstrated optimal selectivity
at low pH and achieved high extractions under near-neutral
pH in a single step. In contrast, the impact of pH on IX was
minimal. Both processes exhibited low selectivity for indi-
vidual PGMs, with CPE at 10% tin (II) chloride showing
the best selectivity, but Pt and Pd recovery was only 50%
at pH 1, and Rh was not extracted. Increasing the reducing
agent in CPE to 20% improved Rh extraction but activated
the recovery of Al, Fe, and Mg.
IX required a shorter incubation time for Pd and Pt
extraction compared to CPE, but it needed 24 hours for
37% Rh extraction, while CPE at 20% tin (II) chloride
achieved 40% extraction in 115 minutes. While these find-
ings suggest the feasibility of CPE for SACs leach metal
concentrations, further comprehensive investigations are
necessary for a robust comparison with existing PGM
extraction methods.
Further work requires exploring the effect of pH on
PGMs and impurity metal extraction in the pH range of
7–14. It is also recommended to extend CPE application to
low-concentration solutions like PGM industry process raf-
finates and waste streams. In addition, research on the recy-
clability of the surfactant phase and impurity scrubbing is
essential. To validate CPE’s commercial potential, piloting,
cost-benefit analyses, and process costing for comparison
with established technologies like solvent extraction is also
recommended.
ACKNOWLEDGMENTS
The authors would like to thank the Department of
Science and Innovation (DSI) and the National Research
Foundation (NRF) for funding under SARChI grant num-
ber 98350.
Figure 4. Effect of contact time on PGMs extraction by IX

1712 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
Kim, M.-S., Kim, B.-S., Kim, E.-Y., Kim, S.-K., Ryu, J.-W.,
&Lee, J.-C. (2011). Recovery of Platinum Group
Metals from the Leach Solution of Spent Automotive
Catalysts by Cementation. Journal of the Korean
Institute of Resources Recycling, 20 (4), 36–45. doi:
10.7844/kirr.2011.20.4.036.
Kolbadinejad, S., &Ghaemi, A. (2023). Recovery
and extraction of platinum from spent catalysts: A
review. Case Studies in Chemical and Environmental
Engineering, 7, 100327.
doi: 10.1016/j.cscee.2023.100327.
Kononova, O.N., Goncharova, E.L., Melnikov, A.M.,
Kashirin, D.M., Kholmogorov, A.G &Konontsev, S.G.
(2010). Ion Exchange Recovery of Rhodium (III) from
Chloride Solutions by Selective Anion Exchangers.
Solvent Extraction and Ion Exchange,28 (3), 388–402.
doi: 10.1080/07366291003684196.
Kumar, K.R., &Shyamala, P. (2019). Catanionic mixed
micellar cloud point extraction of metal ions in coal
fly ash samples and their determination by CS-ETAAS.
Journal of Environmental Chemical Engineering,
7(103119), 1–5. doi: 10.1016/j.jece.2019.103119.
Levan, M.D., &Carta, G. (2008). Adsorption and Ion
Exchange. In D.W. Green &R.H. Perry, Perry’s
Chemical Engineers’ Handbook (8th Ed), (pp.1795–
1799). doi: 10.1036/0071511393.
Le, M.N., Nguyen, T.H., &Lee, M.S. (2018). Comparison
of separation behavior of Ir (IV) and Rh (III) between
tin (II) chloride and ascorbic acid as a reducing agent
in the extraction with Cyanex 921 and Cyanex 301.
Solvent Extraction and Ion Exchange, 36(3), 272–285.
doi: 10.1080/07366299.2018.1478373.
Makua, L., Langa, K., Saguru, C., &Ndlovu, S. (2019).
PGM recovery from a pregnant leach solution using
solvent extraction and cloud point extraction: a pre-
liminary comparison. The Southern African Institute
of Mining and Metallurgy, 119, 453–458. doi:
10.17159/2411-9717/17/484/2019.
Maranon, E., Suárez, F., Alonso, F., Fernández, Y., &
Sastre, H. (1999). Preliminary study of iron removal
from hydrochloric pickling liquor by ion exchange.
Industrial &engineering chemistry research, 38(7),
2782–2786. doi: 10.1021/ie9806895.
Melnyk, A., Namiesnik, J., &Wolska, L. (2015). Theory
and recent applications of coacervate-based extraction
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292. doi: 10.1016/j.trac.2015.03.013.
Mhaske, A.A., &Dhadke, P.M. (2001). Extraction sepa-
ration studies of Rh, Pt and Pd using Cyanex 921 in
toluene—a possible application to recovery from
spent catalysts. Hydrometallurgy, 61(2), 143–150. doi:
10.1016/S0304-386X(01)00152-9.
Morcali, M.H. (2020). A new approach to recover plati-
num-group metals from spent catalytic converters via
iron matte. Resources, Conservation and Recycling, 159,
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Mortada, W.I., Hassanien, M.M., &El-Asmy, A.A.
(2014). Cloud point extraction of some precious
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/j.ejbas.2014.07.001.
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/j.scitotenv.2017.11.350.
Niemelä, M., Huttunen, S.M., Gornostayev, S.S., &
Perämäki, P. (2009). Determination of Pt from coke
samples by ICP-MS after microwave assisted diges-
tion and microwave assisted cloud point extraction.
Microchimica Acta, 166, 255–260. doi: 10.1007
/s00604-009-0194-7.
Panda, R., Jha, M.K., &Pathak, D.D. (2018). Commercial
Processes for the Extraction of Platinum Group Metals
(PGMs). H. Kim et al. (Eds.), Rare Metal Technology
2018, The Minerals, Metals &Materials Society, 119–
130. doi: 10.1007/978-3-319-72350-1_11.
Peng, L.I.U., Liu, G.F., Chen, D.L., Cheng, S.Y., &
Ning, T.A.N.G. (2009). Adsorption properties of Ag
(I), Au (III), Pd (II) and Pt (IV) ions on commercial
717 anion-exchange resin. Transactions of Nonferrous
Metals Society of China, 19(6), 1509–1513. doi:
10.1016/S1003-6326(09)60061-3.
Quina, F.H., &Hinze, W.L. (1999). Surfactant-mediated
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Coulson and Richardson’s chemical engineering:
Volume 2 (5th ed.). Oxford: Butterworth-Heinemann.
Saguru, C.T. (2018). Acid based recovery of PGMs from
spent autocatalytic converters using AlCl3 and HOCl.
(Master’s thesis, University of the Witwatersrand,
Johannesburg). Retrieved from wiredspace.wits.ac.za
/handle/10539/27299.

Previous Page Next Page

Extracted Text (may have errors)

1712 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
Kim, M.-S., Kim, B.-S., Kim, E.-Y., Kim, S.-K., Ryu, J.-W.,
&Lee, J.-C. (2011). Recovery of Platinum Group
Metals from the Leach Solution of Spent Automotive
Catalysts by Cementation. Journal of the Korean
Institute of Resources Recycling, 20 (4), 36–45. doi:
10.7844/kirr.2011.20.4.036.
Kolbadinejad, S., &Ghaemi, A. (2023). Recovery
and extraction of platinum from spent catalysts: A
review. Case Studies in Chemical and Environmental
Engineering, 7, 100327.
doi: 10.1016/j.cscee.2023.100327.
Kononova, O.N., Goncharova, E.L., Melnikov, A.M.,
Kashirin, D.M., Kholmogorov, A.G &Konontsev, S.G.
(2010). Ion Exchange Recovery of Rhodium (III) from
Chloride Solutions by Selective Anion Exchangers.
Solvent Extraction and Ion Exchange,28 (3), 388–402.
doi: 10.1080/07366291003684196.
Kumar, K.R., &Shyamala, P. (2019). Catanionic mixed
micellar cloud point extraction of metal ions in coal
fly ash samples and their determination by CS-ETAAS.
Journal of Environmental Chemical Engineering,
7(103119), 1–5. doi: 10.1016/j.jece.2019.103119.
Levan, M.D., &Carta, G. (2008). Adsorption and Ion
Exchange. In D.W. Green &R.H. Perry, Perry’s
Chemical Engineers’ Handbook (8th Ed), (pp.1795–
1799). doi: 10.1036/0071511393.
Le, M.N., Nguyen, T.H., &Lee, M.S. (2018). Comparison
of separation behavior of Ir (IV) and Rh (III) between
tin (II) chloride and ascorbic acid as a reducing agent
in the extraction with Cyanex 921 and Cyanex 301.
Solvent Extraction and Ion Exchange, 36(3), 272–285.
doi: 10.1080/07366299.2018.1478373.
Makua, L., Langa, K., Saguru, C., &Ndlovu, S. (2019).
PGM recovery from a pregnant leach solution using
solvent extraction and cloud point extraction: a pre-
liminary comparison. The Southern African Institute
of Mining and Metallurgy, 119, 453–458. doi:
10.17159/2411-9717/17/484/2019.
Maranon, E., Suárez, F., Alonso, F., Fernández, Y., &
Sastre, H. (1999). Preliminary study of iron removal
from hydrochloric pickling liquor by ion exchange.
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