1352 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
The extraction of rare earth elements from aqueous
solution involves the use of various chemical pollutants
which are hazardous to the environment. A perfect example
is ammonium bicarbonate used in the enrichment of rare
earth leaching solution which always pollute water bodies
in the environment. Recently, there has been serious push
for more environmentally friendly methods of processing
REEs. A novel local biomass-based method is being devel-
oped at the “CHAR Research Laboratory” of Montana
Technological University for extraction and separation of
REEs. This method involves the use of various feedstocks
to produce biochar which are used to adsorb REEs from
aqueous solution with the aid of resonant vibratory mixing.
Biochar is a carbonaceous material that is produced
when organic matters from animal and plants (biomass)
are heated in the absence of oxygen, a process known as
“pyrolysis”. Historically, biochar is popularly associated
with carbon sequestration, soil amendment, and waste
management (Lehmann et al, 2009). It has been applied
to four major areas in the world which are climate change
alleviation, waste management, energy manufacture and
soil refinement.
According to a publication by Carpenter et al, 1998,
the management of crop and animal wastes generated from
agriculture is worrisome and contributes to pollution of
waters, both ground and surface. Due to the discovery of
the biochar technology, these wastes can be subjected to
the pyrolysis process to convert them to carbon-rich bio-
char products. Biochar also plays important role in soil
remediation because it was observed that it amasses heavy
metals when applied to contaminated soil. Biochar has
been noticed to also function as a source of nutrient to the
soil (Lehmann, 2009) which in turn enhances the quality
of soil. Article published by Lehmann et al in 2009 sug-
gested that the application of biochar to soil is also a way
of sequestering carbon dioxide in the atmosphere. During
the thermal breakdown process of biochar production, the
low oxygen in the beginning of pyrolysis process may be
the source of free radicals, and then carboxyl and carbonyl
functional groups are formed (Shafizadeh, 1982 Brennan
et al, 2001). The molecular properties that biochar exhibit
leads to its capability of reacting with chemicals and reveals
the importance of studying the surface chemistry. The
functional groups that exist on the surfaces of biochar con-
tribute to its adsorption property due to surface charge and
the presence of π electrons, although the pH of the solu-
tion may influence the charge on the functional groups.
As investigated by Radovich et al in 2001, the grouping
Figure 1. Areas of applications of rare earth elements
The extraction of rare earth elements from aqueous
solution involves the use of various chemical pollutants
which are hazardous to the environment. A perfect example
is ammonium bicarbonate used in the enrichment of rare
earth leaching solution which always pollute water bodies
in the environment. Recently, there has been serious push
for more environmentally friendly methods of processing
REEs. A novel local biomass-based method is being devel-
oped at the “CHAR Research Laboratory” of Montana
Technological University for extraction and separation of
REEs. This method involves the use of various feedstocks
to produce biochar which are used to adsorb REEs from
aqueous solution with the aid of resonant vibratory mixing.
Biochar is a carbonaceous material that is produced
when organic matters from animal and plants (biomass)
are heated in the absence of oxygen, a process known as
“pyrolysis”. Historically, biochar is popularly associated
with carbon sequestration, soil amendment, and waste
management (Lehmann et al, 2009). It has been applied
to four major areas in the world which are climate change
alleviation, waste management, energy manufacture and
soil refinement.
According to a publication by Carpenter et al, 1998,
the management of crop and animal wastes generated from
agriculture is worrisome and contributes to pollution of
waters, both ground and surface. Due to the discovery of
the biochar technology, these wastes can be subjected to
the pyrolysis process to convert them to carbon-rich bio-
char products. Biochar also plays important role in soil
remediation because it was observed that it amasses heavy
metals when applied to contaminated soil. Biochar has
been noticed to also function as a source of nutrient to the
soil (Lehmann, 2009) which in turn enhances the quality
of soil. Article published by Lehmann et al in 2009 sug-
gested that the application of biochar to soil is also a way
of sequestering carbon dioxide in the atmosphere. During
the thermal breakdown process of biochar production, the
low oxygen in the beginning of pyrolysis process may be
the source of free radicals, and then carboxyl and carbonyl
functional groups are formed (Shafizadeh, 1982 Brennan
et al, 2001). The molecular properties that biochar exhibit
leads to its capability of reacting with chemicals and reveals
the importance of studying the surface chemistry. The
functional groups that exist on the surfaces of biochar con-
tribute to its adsorption property due to surface charge and
the presence of π electrons, although the pH of the solu-
tion may influence the charge on the functional groups.
As investigated by Radovich et al in 2001, the grouping
Figure 1. Areas of applications of rare earth elements