2626 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
with different reagents at pH =8.0 was measured. As shown
in Figure 2, the zeta potential of clean cassiterite surface
was –21.87 mV, it slightly decreased to –25.13 mV after
the reaction of single kerosene, and sharply decreased to
–72.40 mV after the reaction of single NaOL. The negative
shift of zeta potential on cassiterite surface indicated that
kerosene and NaOL were adsorbed on the cassiterite sur-
face, because kerosene has weak negative charge and NaOL
is an anionic collector[14]. The combination use of NaOL
and kerosene mad the zeta potential on cassiterite surface
further negative, indicated that they were co-adsorbed on
cassiterite surface. The zeta potential on the cassiterite sur-
face, which reacted with kerosene first and then NaOL, had
the largest negative shift, this may be due to the largest co-
adsorption capacity of NaOL and kerosene on its surface.
Effect of NaOL and Kerosene on the Surface Wettability
of Fine Cassiterite
In order to further analyse the influence of reagent adsorp-
tion on the surface wettability of cassiterite, the contact
angle of cassiterite surface before and after the treatment
with different reagent was measured by the sessile drop
method. As shown in Figure 3, the contact angle of the
clean cassiterite surface was 52.74°, and it increased to
71.99° and 80.77° after being treated with kerosene and
NaOL alone, respectively. It was confirmed again that kero-
sene and NaOL adsorbed on cassiterite surface. The hydro-
phobicity of kerosene is much greater than that of NaOL,
but the contact angle of cassiterite surface after kerosene
treatment was smaller than that of NaOL treatment, indi-
cated that the adsorption amount of kerosene on cassiterite
surface was very small. The combination use of kerosene
and NaOL further increased the contact angle of cassiterite
surface, illustrated that the pre-adsorption of kerosene or
NaOL can promote the co-adsorption of the latter added
reagent. Compared with adding NaOL before kerosene,
the contact angle of cassiterite surface treated by adding
kerosene before NaOL was larger, which may be caused by
the larger co-adsorption capacity of the reagent. This result
demonstrated that adding kerosene before NaOL made the
cassiterite surface more hydrophobic, which was an impor-
tant reason for the larger particle size of the induced cas-
siterite aggregates.
Effect of NaOL and Kerosene on the Flotation Recovery
of Fine Cassiterite
In order to verify the floatability of the cassiterite aggre-
gates, the flotation behaviour of the aggregates induced
by different reagent was investigated. From the results in
Figure 4, we can see that the flotation recovery of cassiterite
without reagent treatment was only 7.23%, which was dif-
ficult to recover by flotation. When cassiterite was treated
with kerosene alone, the particle size and hydrophobicity of
cassiterite were slightly increased, but not enough to make
it effective for flotation, and the recovery was only 10.79%.
The single use of NaOL or combination use of kerosene and
NaOL made the flotation recovery of the induced aggre-
gates significantly increased, and the recovery of adding
kerosene first followed by NaOL was the highest, reached
to 81.23%. The results proved that the larger the apparent
particle size and the stronger the surface hydrophobicity,
the more favorable for the flotation of fine cassiterite[15].
52.74
71.99
80.77
88.73
92.03
0
20
40
60
80
100
Without
reagent
Kerosene NaOL Kerosene
+NaOL
NaOL+
Kerosene
Figure 3. Contact angle of cassiterite under different reagent
-21.87 -25.13
-72.40
-77.13
-81.10
-100
-80
-60
-40
-20
0
Without
reagent
Kerosene NaOL Kerosene
+NaOL
NaOL+
Kerosene
Figure 2. Zeta potential of cassiterite under different reagent
Contact
a
le
(°)
Zeta
potenti
(mV)
with different reagents at pH =8.0 was measured. As shown
in Figure 2, the zeta potential of clean cassiterite surface
was –21.87 mV, it slightly decreased to –25.13 mV after
the reaction of single kerosene, and sharply decreased to
–72.40 mV after the reaction of single NaOL. The negative
shift of zeta potential on cassiterite surface indicated that
kerosene and NaOL were adsorbed on the cassiterite sur-
face, because kerosene has weak negative charge and NaOL
is an anionic collector[14]. The combination use of NaOL
and kerosene mad the zeta potential on cassiterite surface
further negative, indicated that they were co-adsorbed on
cassiterite surface. The zeta potential on the cassiterite sur-
face, which reacted with kerosene first and then NaOL, had
the largest negative shift, this may be due to the largest co-
adsorption capacity of NaOL and kerosene on its surface.
Effect of NaOL and Kerosene on the Surface Wettability
of Fine Cassiterite
In order to further analyse the influence of reagent adsorp-
tion on the surface wettability of cassiterite, the contact
angle of cassiterite surface before and after the treatment
with different reagent was measured by the sessile drop
method. As shown in Figure 3, the contact angle of the
clean cassiterite surface was 52.74°, and it increased to
71.99° and 80.77° after being treated with kerosene and
NaOL alone, respectively. It was confirmed again that kero-
sene and NaOL adsorbed on cassiterite surface. The hydro-
phobicity of kerosene is much greater than that of NaOL,
but the contact angle of cassiterite surface after kerosene
treatment was smaller than that of NaOL treatment, indi-
cated that the adsorption amount of kerosene on cassiterite
surface was very small. The combination use of kerosene
and NaOL further increased the contact angle of cassiterite
surface, illustrated that the pre-adsorption of kerosene or
NaOL can promote the co-adsorption of the latter added
reagent. Compared with adding NaOL before kerosene,
the contact angle of cassiterite surface treated by adding
kerosene before NaOL was larger, which may be caused by
the larger co-adsorption capacity of the reagent. This result
demonstrated that adding kerosene before NaOL made the
cassiterite surface more hydrophobic, which was an impor-
tant reason for the larger particle size of the induced cas-
siterite aggregates.
Effect of NaOL and Kerosene on the Flotation Recovery
of Fine Cassiterite
In order to verify the floatability of the cassiterite aggre-
gates, the flotation behaviour of the aggregates induced
by different reagent was investigated. From the results in
Figure 4, we can see that the flotation recovery of cassiterite
without reagent treatment was only 7.23%, which was dif-
ficult to recover by flotation. When cassiterite was treated
with kerosene alone, the particle size and hydrophobicity of
cassiterite were slightly increased, but not enough to make
it effective for flotation, and the recovery was only 10.79%.
The single use of NaOL or combination use of kerosene and
NaOL made the flotation recovery of the induced aggre-
gates significantly increased, and the recovery of adding
kerosene first followed by NaOL was the highest, reached
to 81.23%. The results proved that the larger the apparent
particle size and the stronger the surface hydrophobicity,
the more favorable for the flotation of fine cassiterite[15].
52.74
71.99
80.77
88.73
92.03
0
20
40
60
80
100
Without
reagent
Kerosene NaOL Kerosene
+NaOL
NaOL+
Kerosene
Figure 3. Contact angle of cassiterite under different reagent
-21.87 -25.13
-72.40
-77.13
-81.10
-100
-80
-60
-40
-20
0
Without
reagent
Kerosene NaOL Kerosene
+NaOL
NaOL+
Kerosene
Figure 2. Zeta potential of cassiterite under different reagent
Contact
a
le
(°)
Zeta
potenti
(mV)