2544
Changes in Physicochemical Properties and Flotation Behavior
of Bastnaesite after Mineral Phase Transformation
Qiang Zhang, Yongsheng Sun, Yuexin Han, Peng Gao, Wenbo Li
School of Resources and Civil Engineering, Northeastern University, Shenyang, PR China
National-local Joint Engineering Research Center of High-efficient exploitation technology for Refractory Iron Ore
Resources, Shenyang, PR China
ABSTRACT: The hydrogen-based mineral phase transformation technology was innovatively proposed for
the development of Bayan Obo ores. The effect of roasting on the physicochemical properties and flotation
behavior of bastnaesite was investigated. Bastnaesite was decomposed to produce rare earth oxides, fluorides and
oxyfluorides with complex phase compositions. Compared with natural bastnaesite, the structure of the roasted
particles was severely damaged, many long cracks were formed and the porosity was significantly increased.
Using SHA as a collector and MIBC as a frother, the flotation recovery of roasted products was about 90%, but
new collectors need to be explored to reduce the dosage.
Keywords: Bastnaesite magnetization roasting pyrolysis behavior physicochemical properties flotation
INTRODUCTION
Strategic mineral resources such as iron, rare earth elements
(REEs), niobium, and fluorite are critical to moderniza-
tion (Hou et al., 2020). The Bayan Obo polymetallic ore,
a globally recognized strategic mineral resource, includes
iron, REEs, and fluorite. It possesses large reserves, with
proven iron ore reserves currently estimated at 1.47 bil-
lion tons and world-leading REEs reserves of 100 million
tons (Lai et al., 2013 Q. Zhang et al., 2023a Q. Zhang et
al., 2023b). However, the efficient beneficiation of Bayan
Obo ore has remained a significant challenge due to the
complex mineral composition and close symbiotic rela-
tionships between valuable minerals (Ning et al., 2024). In
recent years, extensive scientific research has focused on the
comprehensive utilization of Bayan Obo ore, resulting in
the development of novel processes such as low-intensity
magnetic separation-high-intensity magnetic separation-
floating for iron and REEs minerals beneficiation, and the
niobium and fluorite beneficiation from tailings (Li et al.,
2014).
Currently, only three concentrates are produced from
the Bayan Obo ore: iron (TFe grade of 65% and recovery of
68%), rare earth (REO grade of 58% and recovery of 35%)
and fluorite (CaF2 grade of 90% and recovery of 30%).
Despite extensive research conducted over the years, the
recoveries of iron, rare earth, and fluorite remain low, while
niobium is essentially underutilized, leading to a significant
waste of resources. The Bayan Obo ore is a representative
iron-bearing rare earth ore (Ning et al., 2024). Studies have
shown that pre-removal of iron minerals facilitates the sub-
sequent beneficiation of REEs minerals (Faris et al., 2017).
Magnetization roasting is proposed to treat iron-containing
Changes in Physicochemical Properties and Flotation Behavior
of Bastnaesite after Mineral Phase Transformation
Qiang Zhang, Yongsheng Sun, Yuexin Han, Peng Gao, Wenbo Li
School of Resources and Civil Engineering, Northeastern University, Shenyang, PR China
National-local Joint Engineering Research Center of High-efficient exploitation technology for Refractory Iron Ore
Resources, Shenyang, PR China
ABSTRACT: The hydrogen-based mineral phase transformation technology was innovatively proposed for
the development of Bayan Obo ores. The effect of roasting on the physicochemical properties and flotation
behavior of bastnaesite was investigated. Bastnaesite was decomposed to produce rare earth oxides, fluorides and
oxyfluorides with complex phase compositions. Compared with natural bastnaesite, the structure of the roasted
particles was severely damaged, many long cracks were formed and the porosity was significantly increased.
Using SHA as a collector and MIBC as a frother, the flotation recovery of roasted products was about 90%, but
new collectors need to be explored to reduce the dosage.
Keywords: Bastnaesite magnetization roasting pyrolysis behavior physicochemical properties flotation
INTRODUCTION
Strategic mineral resources such as iron, rare earth elements
(REEs), niobium, and fluorite are critical to moderniza-
tion (Hou et al., 2020). The Bayan Obo polymetallic ore,
a globally recognized strategic mineral resource, includes
iron, REEs, and fluorite. It possesses large reserves, with
proven iron ore reserves currently estimated at 1.47 bil-
lion tons and world-leading REEs reserves of 100 million
tons (Lai et al., 2013 Q. Zhang et al., 2023a Q. Zhang et
al., 2023b). However, the efficient beneficiation of Bayan
Obo ore has remained a significant challenge due to the
complex mineral composition and close symbiotic rela-
tionships between valuable minerals (Ning et al., 2024). In
recent years, extensive scientific research has focused on the
comprehensive utilization of Bayan Obo ore, resulting in
the development of novel processes such as low-intensity
magnetic separation-high-intensity magnetic separation-
floating for iron and REEs minerals beneficiation, and the
niobium and fluorite beneficiation from tailings (Li et al.,
2014).
Currently, only three concentrates are produced from
the Bayan Obo ore: iron (TFe grade of 65% and recovery of
68%), rare earth (REO grade of 58% and recovery of 35%)
and fluorite (CaF2 grade of 90% and recovery of 30%).
Despite extensive research conducted over the years, the
recoveries of iron, rare earth, and fluorite remain low, while
niobium is essentially underutilized, leading to a significant
waste of resources. The Bayan Obo ore is a representative
iron-bearing rare earth ore (Ning et al., 2024). Studies have
shown that pre-removal of iron minerals facilitates the sub-
sequent beneficiation of REEs minerals (Faris et al., 2017).
Magnetization roasting is proposed to treat iron-containing