3
materials may inhibit these carbonation reactions. These
factors will determine the efficacy of the calcite precipi-
tation process for various mining applications including
stockpile protection from the elements, dust control, and
liquefaction control for tailings and cargo stabilization.
Lastly, we are testing additional biological additives to reach
target values for parameters such as strength and moisture
content.
RESULTS AND DISCUSSION
Microbiome Database/Biobank
Allonnia’s work on the isolation and sequencing of
microbes from mine tailings ponds has demonstrated the
wide genomic diversity present in “inhospitable” mineral-
rich locations. To date, we isolated over 350 fungal and 450
bacterial species (Figure 1). We identified bacteria using
16S amplicon sequencing and fungi using ITS sequencing,
in addition to whole genome sequencing on select isolates.
In samples from several tailings sites, we identified over 25
unique bacterial phyla (the grouping below kingdom in
taxonomic classification) and 11 fungal phyla. Remarkably,
for the fungi over 65% of the isolated species have not
been described in published taxonomy databases, including
some of the most abundant (Figure 2).
Bio-Solubilization
Allonnia’s bio-solvents can effectively solubilize silicate
materials resulting in the removal of gangue components
such as Al, Ca, Mg, and SiO2, while minimizing the loss of
the mineralogical phases with value metals such as lithium
(Li), copper (Cu), nickel (Ni), and iron (Fe). We report a
subset of our results with an ore material and with silicate-
rich tailings here.
Ore Material
The target elements for solubilization from this material
were alumina (Al2O3) and SiO2, which were present in
multiple phases including kaolinite and quartz, as deter-
mined by XRD. Testing was conducted on four samples
with moderately different grades and compositions from
similar ore bodies. One strong performing bio-solvent (Bio-
solvent 1A) was able to achieve the removal of 19 to 31%
of total Al2O3and 22 to 40% of total SiO2 (as measured
by XRF) after two hours of treatment of the pulverized ore
under semi-optimized conditions. This was a single contact
test and additional solubilization is likely with additional
contacts. Further, upon the removal of the alumina and sil-
ica, the target metal increased by 2% to 5% over the same
time (Figure 3).
Based on preliminary data, the relationship between
percent gangue removal and ore grade suggests that removal
is increased with lower ore grades at a solid loading of
almost 40% by weight, similar to typical processing steps
(Figure 4).
In addition, we can refine the bio-solvent composition
and the operational parameters to fine-tune the solubiliza-
tion of the gangue while retaining the value metal. One
Figure 1. Bacteria and Fungi Isolated from Mining Sites
around the World
Figure 2. Abundance of Specific Fungal Genera at Several
Tailings Sites. Colored bar segments show known genera.
Uncharacterized genera are shown with white bars
materials may inhibit these carbonation reactions. These
factors will determine the efficacy of the calcite precipi-
tation process for various mining applications including
stockpile protection from the elements, dust control, and
liquefaction control for tailings and cargo stabilization.
Lastly, we are testing additional biological additives to reach
target values for parameters such as strength and moisture
content.
RESULTS AND DISCUSSION
Microbiome Database/Biobank
Allonnia’s work on the isolation and sequencing of
microbes from mine tailings ponds has demonstrated the
wide genomic diversity present in “inhospitable” mineral-
rich locations. To date, we isolated over 350 fungal and 450
bacterial species (Figure 1). We identified bacteria using
16S amplicon sequencing and fungi using ITS sequencing,
in addition to whole genome sequencing on select isolates.
In samples from several tailings sites, we identified over 25
unique bacterial phyla (the grouping below kingdom in
taxonomic classification) and 11 fungal phyla. Remarkably,
for the fungi over 65% of the isolated species have not
been described in published taxonomy databases, including
some of the most abundant (Figure 2).
Bio-Solubilization
Allonnia’s bio-solvents can effectively solubilize silicate
materials resulting in the removal of gangue components
such as Al, Ca, Mg, and SiO2, while minimizing the loss of
the mineralogical phases with value metals such as lithium
(Li), copper (Cu), nickel (Ni), and iron (Fe). We report a
subset of our results with an ore material and with silicate-
rich tailings here.
Ore Material
The target elements for solubilization from this material
were alumina (Al2O3) and SiO2, which were present in
multiple phases including kaolinite and quartz, as deter-
mined by XRD. Testing was conducted on four samples
with moderately different grades and compositions from
similar ore bodies. One strong performing bio-solvent (Bio-
solvent 1A) was able to achieve the removal of 19 to 31%
of total Al2O3and 22 to 40% of total SiO2 (as measured
by XRF) after two hours of treatment of the pulverized ore
under semi-optimized conditions. This was a single contact
test and additional solubilization is likely with additional
contacts. Further, upon the removal of the alumina and sil-
ica, the target metal increased by 2% to 5% over the same
time (Figure 3).
Based on preliminary data, the relationship between
percent gangue removal and ore grade suggests that removal
is increased with lower ore grades at a solid loading of
almost 40% by weight, similar to typical processing steps
(Figure 4).
In addition, we can refine the bio-solvent composition
and the operational parameters to fine-tune the solubiliza-
tion of the gangue while retaining the value metal. One
Figure 1. Bacteria and Fungi Isolated from Mining Sites
around the World
Figure 2. Abundance of Specific Fungal Genera at Several
Tailings Sites. Colored bar segments show known genera.
Uncharacterized genera are shown with white bars