1
25-008
Alternative Methodology for Selecting and Formulating
Collectors for Coarse Fractions Using Metallurgical and
Statistical Analysis
Cristian Saavedra
Clariant, Chile
Patricio Zarate
Clariant, Chile
INTRODUCTION
Flotation collectors play a crucial role in mineral flotation
by selectively adhering to mineral surfaces and aiding in
their separation from gangue material. They are heteropo-
lar molecules, as defined by Sutherland and Wark (1955),
featuring non-polar hydrocarbon chains and polar groups
interacting with mineral surfaces to induce hydrophobicity
selectively.
The importance of collectors in mineral processing, as
underscored by Lotter and Bradshaw (2010), lies in their
ability to enhance recovery rates and improve selectivity,
thereby optimizing the extraction of valuable minerals from
complex ores. Collectors are classified based on their mech-
anism of action, as proposed by Laskowski (2010). This
classification categorizes collectors into three groups: water-
soluble compounds, water-insoluble “oily” collectors, and
water-insoluble amphipathic compounds forming molecu-
lar films at the water/gas interface. This complements the
chemical structure-based classification by Sutherland and
Wark (1955) and Suoninen and Laajalehto (1993), offer-
ing a comprehensive understanding of collector diversity
in flotation systems. Collector selection is an iterative pro-
cess crucial for optimizing mineral processing efficiency, as
emphasized by Lotter and Bradshaw (2010).
Understanding the significance of collector mixing
or synergy outcomes is paramount for enhancing mineral
flotation efficiency and sustainability. Taguta, O’Connor,
and McFadzean (2018) demonstrate that mixed collector
systems enhance interaction enthalpies and microflotation
recoveries, indicating improved performance. McFadzean,
Castelyn, and O’Connor (2012), along with Critchley and
Riaz (1991), delve into investigating synergistic interactions
between collectors, offering insights for strategic selection.
Observations from the study of collector synergy, as noted
by Wakamatsu et al. (1980), reveal nuanced relationships
surpassing individual collector behaviors.
The methodology outlined in this paper provides valu-
able guidance for classifying and selecting collectors based
on specific application needs, while also suggesting the
potential for synergistically improving recovery across fine,
intermediate, and coarse particles.
METHODOLOGY
In this study, thirteen collectors from various chemical fam-
ilies in Clariant’s product portfolio were evaluated, and five
key metallurgical responses were analyzed: copper recov-
ery and copper distribution by size fractions of –75 μm,
+75 μm, +150 μm, and +210 μm. The aim was to identify
the collectors that achieved the highest copper recoveries
and to assess their capacity to reduce copper losses across
different size fractions in flotation tailings. The objective
was to classify and select collectors according to specific
needs, and/or explore future combinations that allow for-
mulating collector mixtures to improve the recovery of fine,
intermediate, and/or coarse particles.
Characterization of Flotation Feed
A chemical assay was conducted to determine the copper
(Cu), iron (Fe), and molybdenum (Mo) content in the
feed. Using the QEMSCAN technique, the minerals pres-
ent in the flotation feed were identified and quantified,
and the liberation of valuable minerals by particle size was
determined. Additionally, a sieving analysis using ASTM
standard sieves (meshes 16, 30, 40, 50, 70, 100, 200, and
–200) determined the particle size distribution in the flota-
tion feed.
Flotation Tests
A sample of Cu-Mo sulphide ore from northern Chile was
used in the batch flotation tests. The as-received sample was
100% below size 10 ASTM mesh (2.0 mm). This sample
was further ground in a Marcy type steel ball mill (5.4 L
25-008
Alternative Methodology for Selecting and Formulating
Collectors for Coarse Fractions Using Metallurgical and
Statistical Analysis
Cristian Saavedra
Clariant, Chile
Patricio Zarate
Clariant, Chile
INTRODUCTION
Flotation collectors play a crucial role in mineral flotation
by selectively adhering to mineral surfaces and aiding in
their separation from gangue material. They are heteropo-
lar molecules, as defined by Sutherland and Wark (1955),
featuring non-polar hydrocarbon chains and polar groups
interacting with mineral surfaces to induce hydrophobicity
selectively.
The importance of collectors in mineral processing, as
underscored by Lotter and Bradshaw (2010), lies in their
ability to enhance recovery rates and improve selectivity,
thereby optimizing the extraction of valuable minerals from
complex ores. Collectors are classified based on their mech-
anism of action, as proposed by Laskowski (2010). This
classification categorizes collectors into three groups: water-
soluble compounds, water-insoluble “oily” collectors, and
water-insoluble amphipathic compounds forming molecu-
lar films at the water/gas interface. This complements the
chemical structure-based classification by Sutherland and
Wark (1955) and Suoninen and Laajalehto (1993), offer-
ing a comprehensive understanding of collector diversity
in flotation systems. Collector selection is an iterative pro-
cess crucial for optimizing mineral processing efficiency, as
emphasized by Lotter and Bradshaw (2010).
Understanding the significance of collector mixing
or synergy outcomes is paramount for enhancing mineral
flotation efficiency and sustainability. Taguta, O’Connor,
and McFadzean (2018) demonstrate that mixed collector
systems enhance interaction enthalpies and microflotation
recoveries, indicating improved performance. McFadzean,
Castelyn, and O’Connor (2012), along with Critchley and
Riaz (1991), delve into investigating synergistic interactions
between collectors, offering insights for strategic selection.
Observations from the study of collector synergy, as noted
by Wakamatsu et al. (1980), reveal nuanced relationships
surpassing individual collector behaviors.
The methodology outlined in this paper provides valu-
able guidance for classifying and selecting collectors based
on specific application needs, while also suggesting the
potential for synergistically improving recovery across fine,
intermediate, and coarse particles.
METHODOLOGY
In this study, thirteen collectors from various chemical fam-
ilies in Clariant’s product portfolio were evaluated, and five
key metallurgical responses were analyzed: copper recov-
ery and copper distribution by size fractions of –75 μm,
+75 μm, +150 μm, and +210 μm. The aim was to identify
the collectors that achieved the highest copper recoveries
and to assess their capacity to reduce copper losses across
different size fractions in flotation tailings. The objective
was to classify and select collectors according to specific
needs, and/or explore future combinations that allow for-
mulating collector mixtures to improve the recovery of fine,
intermediate, and/or coarse particles.
Characterization of Flotation Feed
A chemical assay was conducted to determine the copper
(Cu), iron (Fe), and molybdenum (Mo) content in the
feed. Using the QEMSCAN technique, the minerals pres-
ent in the flotation feed were identified and quantified,
and the liberation of valuable minerals by particle size was
determined. Additionally, a sieving analysis using ASTM
standard sieves (meshes 16, 30, 40, 50, 70, 100, 200, and
–200) determined the particle size distribution in the flota-
tion feed.
Flotation Tests
A sample of Cu-Mo sulphide ore from northern Chile was
used in the batch flotation tests. The as-received sample was
100% below size 10 ASTM mesh (2.0 mm). This sample
was further ground in a Marcy type steel ball mill (5.4 L