2272 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
is a signature of the dangling (not-coordinated) sophorose
group. It is further supported by the fact that the adsorp-
tion of carboxylates on CeO2 causes the CeIV reduction
[35]. Finally, the LSL adsorption through the sophorose
group imparts the opposite effect. Hence, at pH 4, the car-
boxylic group of ASL competes with the sophorose group
for the ceria surface, which explains the poor collecting per-
formance of ASL in the separation of ceria from hematite
at pH 4 (Figure 8). In contrast, LSL is adsorbed though the
sophorose group, rendering CeO2(red) superhydrophobic,
which results in their hydrophobic agglomeration [13].
red
537 534 531 528
Binding Energy (eV)
930 920 910 900 890 880
Binding Energy (eV)
296 292 288 284
Binding Energy (eV)
CeO2(red)+LSL
a Ce 3d b c O 1s C 1s
ads LSL
ads LSL
ads LSL
Figure 11. XPS (a) Ce 3d, (b) O 1s, and (c) C 1s spectra of initial (brown) CeO
2
(red) and (green) after conditioning in 100 mM
LSL solution at pH 4 LSL for 2 h
CeO2(ox)+ASL
536 534 532 530 528
Binding Energy (eV)
925 920 915 910 905 900 895 890 885 880
Binding Energy (eV)
294 291 288 285 282
Binding Energy (eV)
a Ce 3d b c O 1s C 1s
ads ASL
ads ASL
ads ASL
Figure 12. XPS (a) Ce 3d, (b) O 1s, and (c) C 1s spectra of initial (brown) CeO
2
(ox) and (green) after conditioning in 100 mM
LSL solution at pH 4 ASL for 2 h. Arrow in (c) shows the C 1s component due to the sophorose group
Table 5. XPS total C/Ce and N/Ce (for BHA) atomic ratios for –20 µm CeO2(red) and CeO2(ox) after their conditioning in
water and 100 µM solutions of BHA, ASL, and LSL, all at pH 4, for 2h. To prepare the samples, 0.5 g of the particles were
added into a 50 mL solution at initial pH 4.0 ± 0.1. pH 4 adjusted with HNO3
C/Ce atomic ratio N/Ce atomic ratio
CeO2(red) CeO2(°x) CeO2(red) CeO2(°x)
H
2 O 2.7 2.2
BHA 1.4 1.5 0.20 0.22
ASL 3.2 3.4
LSL 6.0 3.7
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is a signature of the dangling (not-coordinated) sophorose
group. It is further supported by the fact that the adsorp-
tion of carboxylates on CeO2 causes the CeIV reduction
[35]. Finally, the LSL adsorption through the sophorose
group imparts the opposite effect. Hence, at pH 4, the car-
boxylic group of ASL competes with the sophorose group
for the ceria surface, which explains the poor collecting per-
formance of ASL in the separation of ceria from hematite
at pH 4 (Figure 8). In contrast, LSL is adsorbed though the
sophorose group, rendering CeO2(red) superhydrophobic,
which results in their hydrophobic agglomeration [13].
red
537 534 531 528
Binding Energy (eV)
930 920 910 900 890 880
Binding Energy (eV)
296 292 288 284
Binding Energy (eV)
CeO2(red)+LSL
a Ce 3d b c O 1s C 1s
ads LSL
ads LSL
ads LSL
Figure 11. XPS (a) Ce 3d, (b) O 1s, and (c) C 1s spectra of initial (brown) CeO
2
(red) and (green) after conditioning in 100 mM
LSL solution at pH 4 LSL for 2 h
CeO2(ox)+ASL
536 534 532 530 528
Binding Energy (eV)
925 920 915 910 905 900 895 890 885 880
Binding Energy (eV)
294 291 288 285 282
Binding Energy (eV)
a Ce 3d b c O 1s C 1s
ads ASL
ads ASL
ads ASL
Figure 12. XPS (a) Ce 3d, (b) O 1s, and (c) C 1s spectra of initial (brown) CeO
2
(ox) and (green) after conditioning in 100 mM
LSL solution at pH 4 ASL for 2 h. Arrow in (c) shows the C 1s component due to the sophorose group
Table 5. XPS total C/Ce and N/Ce (for BHA) atomic ratios for –20 µm CeO2(red) and CeO2(ox) after their conditioning in
water and 100 µM solutions of BHA, ASL, and LSL, all at pH 4, for 2h. To prepare the samples, 0.5 g of the particles were
added into a 50 mL solution at initial pH 4.0 ± 0.1. pH 4 adjusted with HNO3
C/Ce atomic ratio N/Ce atomic ratio
CeO2(red) CeO2(°x) CeO2(red) CeO2(°x)
H
2 O 2.7 2.2
BHA 1.4 1.5 0.20 0.22
ASL 3.2 3.4
LSL 6.0 3.7
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