A Novel Collector 5–(Butylthio)–1,3,4–Thiadiazole–2–Thiol …
647
complexes. We can also confirm the excellent selectivity again of CSC-1 collector
towards galena in flotation separation by obvious difference value of Gibbs free
energy and distortion energy in CSC-1–M
2+ complex.
Conclusions
In this study, a novel selective collector 5–(butylthio)–1,3,4–thiadiazole–2–thiol
(CSC-1) was synthesized by modifying the molecular structure of xanthate. The
results of the flotation tests prove that under the optimized reagent scheme, CSC-1
collector could significantly improve the flotation recoveries and the grades of Zn and
Pb rather than Fe, while EX collector mediates these three minerals poorly and nonselectively. Next, the results of flotation tests were demonstrated by contact angle
and zeta potential measurements: using CSC-1 as the collector, the adsorption on
sphalerite and galena surfaces is much stronger than that on pyrite surface. However,
using EX as the collector, the adsorption on pyrite, sphalerite, and galena surfaces
is minor and similar. Furthermore, DFT calculation results provided insight into the
mechanism. EPS and NCP studies of collectors proved that aza-framework of CSC1 molecule are responsible for the excellent flotation selectivity. ELF study reveals
that CSC-1 molecule is more likely to bind to Pb
2+ and these inferences were further
proven by distortion energy and Gibbs free energy in optimized molecular geometry: Pb
2+ is the optimum metal ion to reduce fused ring tension of collector–M
2+
complexes, and CSC-1–Pb
2+ coordination is also the most stable chelation modes in
CSC-1–M
2+ complexes. In summary, CSC-1 can be used for flotation separation of
galena and sphalerite from pyrite and has a great potential for industrial application.
References
1. Christopher P, Linic S (2008) Engineering selectivity in heterogeneous catalysis: Ag nanowires
as selective ethylene epoxidation catalysts. J Am Chem Soc 130:11264–11265
2. Liu G, Yang X, Zhong H (2017) Molecular design of flotation collectors: a recent progress.
Adv Colloid Interface Sci 246:181–195
3. Mu Y, Peng Y, Lauten RA (2016) The depression of pyrite in selective flotation by different
reagent systems—a literature review. Miner Eng 96–97:143–156
4. Ghirlanda G (2008) Old enzymes, new tricks. Nature 453:164–166
5. Kaiser ET (2010) Catalytic activity of enzymes altered at their active sites. Angew Chem Int
Ed 27:913–922
6. Pecina Treviño ET, Uribe Salas A, Nava Alonso F et al (2003) On the sodium-diisobutyl
dithiophosphinate (Aerophine 3418A) interaction with activated and unactivated galena and
pyrite. Int J Miner Process 71:201–217
7. Huang Z, Wang J, Sun W et al (2019) Selective flotation of chalcopyrite from pyrite using
diphosphonic acid as collector. Miner Eng 140:105890
8. Nowak P, Laajalehto K (2007) On the interpretation of the XPS spectra of adsorbed layers
of flotation collectors—ethyl xanthate on metallic lead. Physicochem Probl Miner Process
41:107–116
647
complexes. We can also confirm the excellent selectivity again of CSC-1 collector
towards galena in flotation separation by obvious difference value of Gibbs free
energy and distortion energy in CSC-1–M
2+ complex.
Conclusions
In this study, a novel selective collector 5–(butylthio)–1,3,4–thiadiazole–2–thiol
(CSC-1) was synthesized by modifying the molecular structure of xanthate. The
results of the flotation tests prove that under the optimized reagent scheme, CSC-1
collector could significantly improve the flotation recoveries and the grades of Zn and
Pb rather than Fe, while EX collector mediates these three minerals poorly and nonselectively. Next, the results of flotation tests were demonstrated by contact angle
and zeta potential measurements: using CSC-1 as the collector, the adsorption on
sphalerite and galena surfaces is much stronger than that on pyrite surface. However,
using EX as the collector, the adsorption on pyrite, sphalerite, and galena surfaces
is minor and similar. Furthermore, DFT calculation results provided insight into the
mechanism. EPS and NCP studies of collectors proved that aza-framework of CSC1 molecule are responsible for the excellent flotation selectivity. ELF study reveals
that CSC-1 molecule is more likely to bind to Pb
2+ and these inferences were further
proven by distortion energy and Gibbs free energy in optimized molecular geometry: Pb
2+ is the optimum metal ion to reduce fused ring tension of collector–M
2+
complexes, and CSC-1–Pb
2+ coordination is also the most stable chelation modes in
CSC-1–M
2+ complexes. In summary, CSC-1 can be used for flotation separation of
galena and sphalerite from pyrite and has a great potential for industrial application.
References
1. Christopher P, Linic S (2008) Engineering selectivity in heterogeneous catalysis: Ag nanowires
as selective ethylene epoxidation catalysts. J Am Chem Soc 130:11264–11265
2. Liu G, Yang X, Zhong H (2017) Molecular design of flotation collectors: a recent progress.
Adv Colloid Interface Sci 246:181–195
3. Mu Y, Peng Y, Lauten RA (2016) The depression of pyrite in selective flotation by different
reagent systems—a literature review. Miner Eng 96–97:143–156
4. Ghirlanda G (2008) Old enzymes, new tricks. Nature 453:164–166
5. Kaiser ET (2010) Catalytic activity of enzymes altered at their active sites. Angew Chem Int
Ed 27:913–922
6. Pecina Treviño ET, Uribe Salas A, Nava Alonso F et al (2003) On the sodium-diisobutyl
dithiophosphinate (Aerophine 3418A) interaction with activated and unactivated galena and
pyrite. Int J Miner Process 71:201–217
7. Huang Z, Wang J, Sun W et al (2019) Selective flotation of chalcopyrite from pyrite using
diphosphonic acid as collector. Miner Eng 140:105890
8. Nowak P, Laajalehto K (2007) On the interpretation of the XPS spectra of adsorbed layers
of flotation collectors—ethyl xanthate on metallic lead. Physicochem Probl Miner Process
41:107–116