3134
The Combined Depression of Calcium Chloride and Sodium
Humate in the Flotation Separation of Pyrite from Galena
Under Low Alkalinity
Yanfang Cui, Fen Jiao, Wenqing Qin, Xinchun Li, Qian Wei
School of Minerals Processing and Bioengineering, Central South University, Changsha, China
Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing
Mineral Resources, Central South University, Changsha, China
ABSTRACT: In this study, CaCl2 and sodium humate (NaHA) were employed as the mixed depressant for the
separation of galena from pyrite. Micro-flotation results showed that the recovery difference was more than 60%
between the galena and pyrite at pH 6–10 when the CaCl2 and NaHA concentration was 4 mg/L and 50 mg/L,
respectively. Ca2+ could selectively promote the NaHA adsorption on the pyrite surface, thus hindering the
adsorption of the collector. Moreover, the adsorption of NaHA on the surface of the minerals weakened the
electron transfer, and then reduce the galvanic interaction between galena and pyrite.
Keywords: Galena Pyrite Selective flotation Calcium chloride and Sodium humate Combined depressant
Low alkalinity
INTRODUCTION
Lead is an important non-ferrous raw material that play an
extremely important role in the development of national
economy [1,2]. Lead have many applications, such as elec-
trical industry and military industry[3,4]. Galena is a major
source of lead [5]. Pyrite is the most widely distributed sul-
fide mineral in the Earth’s crust. It is usually associated with
other minerals, such as galena [6,7]. In the flotation pro-
cess, pyrite is one of the main minerals that affecting the
separation of polymetallic sulfide minerals and the grade of
concentrate. It has become the key to depress pyrite effec-
tively in the flotation separation of galena and pyrite.
vIn present, the depression of pyrite usually use a large
amount of lime in the flotation process of sulfide ores
[8–10]. However, the high alkaline environment is very
easy to depress the fine grained useful minerals and asso-
ciated rare and precious metal minerals, resulting in low
recovery and low rate of comprehensive utilization of min-
eral resources. At the same time, flotation foam sticky and
slime entrained seriously under high alkali conditions lime
is easy to scale and clog the pipeline, which is not conducive
to production operation and index stability the amount
of sulfuric acid in the subsequent tailings flotation desul-
furization process is increased, thus worsening the work-
ing environment. Therefore, it is imperative to effectively
depress pyrite under low alkaline condition.
Nowadays, more and more researchers pay attention
to the depression of pyrite under low alkaline conditions.
The depressants used for pyrite mainly include inorganic,
organic and combined depressants. Inorganic depressants
The Combined Depression of Calcium Chloride and Sodium
Humate in the Flotation Separation of Pyrite from Galena
Under Low Alkalinity
Yanfang Cui, Fen Jiao, Wenqing Qin, Xinchun Li, Qian Wei
School of Minerals Processing and Bioengineering, Central South University, Changsha, China
Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing
Mineral Resources, Central South University, Changsha, China
ABSTRACT: In this study, CaCl2 and sodium humate (NaHA) were employed as the mixed depressant for the
separation of galena from pyrite. Micro-flotation results showed that the recovery difference was more than 60%
between the galena and pyrite at pH 6–10 when the CaCl2 and NaHA concentration was 4 mg/L and 50 mg/L,
respectively. Ca2+ could selectively promote the NaHA adsorption on the pyrite surface, thus hindering the
adsorption of the collector. Moreover, the adsorption of NaHA on the surface of the minerals weakened the
electron transfer, and then reduce the galvanic interaction between galena and pyrite.
Keywords: Galena Pyrite Selective flotation Calcium chloride and Sodium humate Combined depressant
Low alkalinity
INTRODUCTION
Lead is an important non-ferrous raw material that play an
extremely important role in the development of national
economy [1,2]. Lead have many applications, such as elec-
trical industry and military industry[3,4]. Galena is a major
source of lead [5]. Pyrite is the most widely distributed sul-
fide mineral in the Earth’s crust. It is usually associated with
other minerals, such as galena [6,7]. In the flotation pro-
cess, pyrite is one of the main minerals that affecting the
separation of polymetallic sulfide minerals and the grade of
concentrate. It has become the key to depress pyrite effec-
tively in the flotation separation of galena and pyrite.
vIn present, the depression of pyrite usually use a large
amount of lime in the flotation process of sulfide ores
[8–10]. However, the high alkaline environment is very
easy to depress the fine grained useful minerals and asso-
ciated rare and precious metal minerals, resulting in low
recovery and low rate of comprehensive utilization of min-
eral resources. At the same time, flotation foam sticky and
slime entrained seriously under high alkali conditions lime
is easy to scale and clog the pipeline, which is not conducive
to production operation and index stability the amount
of sulfuric acid in the subsequent tailings flotation desul-
furization process is increased, thus worsening the work-
ing environment. Therefore, it is imperative to effectively
depress pyrite under low alkaline condition.
Nowadays, more and more researchers pay attention
to the depression of pyrite under low alkaline conditions.
The depressants used for pyrite mainly include inorganic,
organic and combined depressants. Inorganic depressants