682 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
deionized water accompanied by 5 min magnetic stirring,
and 0.2 g of TC was dispersed in the solution with bath
sonication and another 30 min stirring. Then, refriger-
ated NaBH4 solution was put into the suspension drop-
wise. ATC was collected after the final 30 min stirring and
high-speed centrifugation. (2) MTC synthesis: 0.24 g of
Na2MoO4·2H2O and 0.075 g of C2H5NS were added into
50 mL of deionized water with 10 min continuous stirring
to form a transparent solution. Subsequently, 0.2 g of TC
was immersed in the solution with sonication for 5 min to
obtain a suspension. Afterward, a certain amount of CTAB
was put into the mixed slurry with another 30 min mag-
netic stirring. Next, the suspension was transferred into
the autoclave and maintained at 180 °C for 24 h. MTC
photocatalysts were obtained through final washing, cen-
trifugation and calcination under Ar atmosphere. (3) BTC
synthesis: 0.01 g of Bi(NO3)3·5H2O was dissolved in 50
mL of deionized water with stirring for 10 min. Then, 0.2 g
of TC was added into the solution with bath sonication
for 5 min. Next, NaCl solution was dropwise added into
the suspension, and transferred into a water bath kettle to
keep a constant temperature of 50 °C with 2 h continuous
stirring.
Photodegradation Performance Evaluation
To evaluate the photodegradation performance of the
composite photocatalysts, a series of experiments were
conducted using a photochemical reactor (PL-03, Beijing
Pulinsaisi plant, China). For TC composites, a high-pres-
sure mercury lamp at 300 W was applied. In a typical
experimental procedure, 50 mg of the photocatalysts were
added into 50 mL of sodium isopropyl xanthate (SIPX)
solution with an initial concentration of 20 mg/L. Before
irradiation, 30 min dark adsorption procedure was con-
ducted to achieve the adsorption-desorption equilibrium of
xanthate over the photocatalyst surface. 4 mL of suspen-
sion was extracted by a plastic straw during every 5 min
irradiation interval. After high-speed centrifugation, the
solution absorbance was measured using UV–vis absorp-
tion spectrophotometer (UV1901PC, Shanghai AuCy
Instrument) according to the strong characteristic peak of
SIPX at 301 nm (Figure 2a). Based on the absorbance mea-
surement results in Figure 2b, it can be found that there is
a good linear relationship between SIPX concentration and
absorbance. Therefore, the degradation efficiency (D) of all
samples can be determined by Eq. (1) as follows.
D C
C C
A
A A
100%
0
0
0
0 #=
-
=
-
(1)
Herein, A0, A, and C0, C represent the absorbance values
and SIPX concentrations when the reaction times were 0
and t, respectively. Besides, the pseudo-first-order kinetic
model is appropriate for the degradation processes of all
samples. k is the degradation rate constant, which can be
determined by the slope of the fitting lines.
lnb C
C
kt 0 =l (2)
For the operation of ternary composites, the light
source of the photochemical reactor was changed into a
400 W Xe lamp to irradiate visible light. Furthermore, the
dark adsorption process and irradiation interval will pro-
long to 1 h and 30 min, respectively.
Figure 2. (a) UV-vis absorption spectrum and (b) standard curve of SIPX
deionized water accompanied by 5 min magnetic stirring,
and 0.2 g of TC was dispersed in the solution with bath
sonication and another 30 min stirring. Then, refriger-
ated NaBH4 solution was put into the suspension drop-
wise. ATC was collected after the final 30 min stirring and
high-speed centrifugation. (2) MTC synthesis: 0.24 g of
Na2MoO4·2H2O and 0.075 g of C2H5NS were added into
50 mL of deionized water with 10 min continuous stirring
to form a transparent solution. Subsequently, 0.2 g of TC
was immersed in the solution with sonication for 5 min to
obtain a suspension. Afterward, a certain amount of CTAB
was put into the mixed slurry with another 30 min mag-
netic stirring. Next, the suspension was transferred into
the autoclave and maintained at 180 °C for 24 h. MTC
photocatalysts were obtained through final washing, cen-
trifugation and calcination under Ar atmosphere. (3) BTC
synthesis: 0.01 g of Bi(NO3)3·5H2O was dissolved in 50
mL of deionized water with stirring for 10 min. Then, 0.2 g
of TC was added into the solution with bath sonication
for 5 min. Next, NaCl solution was dropwise added into
the suspension, and transferred into a water bath kettle to
keep a constant temperature of 50 °C with 2 h continuous
stirring.
Photodegradation Performance Evaluation
To evaluate the photodegradation performance of the
composite photocatalysts, a series of experiments were
conducted using a photochemical reactor (PL-03, Beijing
Pulinsaisi plant, China). For TC composites, a high-pres-
sure mercury lamp at 300 W was applied. In a typical
experimental procedure, 50 mg of the photocatalysts were
added into 50 mL of sodium isopropyl xanthate (SIPX)
solution with an initial concentration of 20 mg/L. Before
irradiation, 30 min dark adsorption procedure was con-
ducted to achieve the adsorption-desorption equilibrium of
xanthate over the photocatalyst surface. 4 mL of suspen-
sion was extracted by a plastic straw during every 5 min
irradiation interval. After high-speed centrifugation, the
solution absorbance was measured using UV–vis absorp-
tion spectrophotometer (UV1901PC, Shanghai AuCy
Instrument) according to the strong characteristic peak of
SIPX at 301 nm (Figure 2a). Based on the absorbance mea-
surement results in Figure 2b, it can be found that there is
a good linear relationship between SIPX concentration and
absorbance. Therefore, the degradation efficiency (D) of all
samples can be determined by Eq. (1) as follows.
D C
C C
A
A A
100%
0
0
0
0 #=
-
=
-
(1)
Herein, A0, A, and C0, C represent the absorbance values
and SIPX concentrations when the reaction times were 0
and t, respectively. Besides, the pseudo-first-order kinetic
model is appropriate for the degradation processes of all
samples. k is the degradation rate constant, which can be
determined by the slope of the fitting lines.
lnb C
C
kt 0 =l (2)
For the operation of ternary composites, the light
source of the photochemical reactor was changed into a
400 W Xe lamp to irradiate visible light. Furthermore, the
dark adsorption process and irradiation interval will pro-
long to 1 h and 30 min, respectively.
Figure 2. (a) UV-vis absorption spectrum and (b) standard curve of SIPX