Allanite-derived rare-earth leachate secondary resource
A rare-earth-bearing processing liquor generated from allanite ore, represented here by the chemically purified and reconstituted Halleck Creek, Wyoming feed used by Lu et al. (2026). Acid leaching, impurity precipitation, REE hydroxide precipitation and hydrochloric-acid redissolution precede the biological-reagent experiment. This processing intermediate is distinct from geological ore, beneficiated allanite concentrate, a pure allanite species and an isolated REE product. Its classification reflects chemical processing, not extraction alone. No criticality designation is inherited from its constituents.
Microbial & Biochemical Mechanisms (1)
Yeast-produced oxalate precipitates REEs from prepared leachate
biomineralization
Microbial
Associated Organisms:
Pichia kudriavzevii (NCBITaxon:4909)
Oxalate-containing culture supernatant from engineered JL04, derived from source-named Issatchenkia orientalis SD108, induced precipitation and decreased dissolved REE concentrations in a chemically prepared allanite-derived liquor. The REE stage used centrifuged supernatant, not intact yeast or direct microbial ore leaching. The reported over 99% total-REE removal near a source-nominal 2.7 g/L oxalic-acid dose is solution depletion under laboratory conditions, not an ore-to-product or isolated-pure-product yield. Industrial deployment and general superiority over commercial oxalic acid were not established.
Experimental Context & Analytical Limits:
Halleck Creek ore was density-concentrated, ground to a top size of 150 micrometres and HCl-leached at 75 degrees C, 30% solids by weight and a reported acid-to-solid ratio of 0.3:1 for 2 h. Hydrogen peroxide oxidation and staged NaOH additions removed Fe/silica and Al; REEs were precipitated at pH 8, redissolved using 12 M HCl, diluted to 310 mL and filtered to remove manganese hydroxide. Separately, JL04 glucose-fed SC-URA cultures were produced in 100 mL bioreactors at 30 degrees C, pH 4 and 10% dissolved-oxygen setting. Culture was centrifuged at 8000 x g for 30 min before use. Real-liquor tests compared source-labelled 22.00 and 42.70 g/L oxalate supernatants with 1 M commercial oxalic acid while mixing and maintaining pH 1.5 with 5 M NaOH. The workbook records sequential reagent additions and 1.5 mL withdrawals; initial liquid volumes were 95 mL in biological-reagent arms and 100 mL in the commercial arm. These dose points are not independent replicates: Methods state n=1 per real-leachate condition. Real-liquor precipitation duration and temperature are not separately specified; overnight room-temperature conditions belong to the synthetic single-salt assays and are not transferred. No matched parental-supernatant or uninoculated-medium real-liquor comparator is documented in the inspected main article and Data 1. Species-level taxonomy does not resolve engineered-strain identity or the effects of the broth matrix.
Halleck Creek ore was density-concentrated, ground to a top size of 150 micrometres and HCl-leached at 75 degrees C, 30% solids by weight and a reported acid-to-solid ratio of 0.3:1 for 2 h. Hydrogen peroxide oxidation and staged NaOH additions removed Fe/silica and Al; REEs were precipitated at pH 8, redissolved using 12 M HCl, diluted to 310 mL and filtered to remove manganese hydroxide. Separately, JL04 glucose-fed SC-URA cultures were produced in 100 mL bioreactors at 30 degrees C, pH 4 and 10% dissolved-oxygen setting. Culture was centrifuged at 8000 x g for 30 min before use. Real-liquor tests compared source-labelled 22.00 and 42.70 g/L oxalate supernatants with 1 M commercial oxalic acid while mixing and maintaining pH 1.5 with 5 M NaOH. The workbook records sequential reagent additions and 1.5 mL withdrawals; initial liquid volumes were 95 mL in biological-reagent arms and 100 mL in the commercial arm. These dose points are not independent replicates: Methods state n=1 per real-leachate condition. Real-liquor precipitation duration and temperature are not separately specified; overnight room-temperature conditions belong to the synthetic single-salt assays and are not transferred. No matched parental-supernatant or uninoculated-medium real-liquor comparator is documented in the inspected main article and Data 1. Species-level taxonomy does not resolve engineered-strain identity or the effects of the broth matrix.
Curated Evidence Points:
Support
Source:
lu2026
Figure 3b, Results and Precipitation test support dose-associated REE solution depletion by yeast-derived and commercial oxalate. Methods report centrifugation/filtration of precipitates and ICP-OES analysis, but the headline recovery is calculated from residual solution concentrations. The commercial comparator supports similar observed removal in this assay; n=1 does not establish statistical equivalence or replicated performance.
Partial
Source:
lu2026_data1
Analysis sheets correct concentrations for cumulative reagent volume and sampling. Row 74 gives over 99% total-REE depletion in all three arms near their nominal 2.7 g/L doses. Dose formulas use a fixed 100 mL denominator even for the 95 mL biological arms; these values are not asserted as actual final reactor concentrations. TREE uses the source's 16-element sum, with Sc included among its light REEs. This is not a closed process mass balance.
Partial
Source:
lu2026_data1
Raw feed rows include Th and U; their high-dose zero cells generate 100% apparent removal without stated per-cell detection or censoring limits. This raises possible co-retention, not proof of absence or product purity. Negative apparent removals, especially for Mg and the first biological-A total-REE point, remain source calculation limitations and are not clamped to zero. OAP-A row 74 reports Mn removal about 6.89%, contrary to the text's blanket less-than-6% statement for Ca, Mg, Mn and Zn. Missing cells are not interpreted as zeros. No universal high-purity mixed-REE product claim is made.
Partial
Source:
lu2026_supplement
Table 1 and strain-construction methods identify engineered JL04. Figure S8 supplies the separate 22 g/L supernatant real-liquor arm. Table 3 and main Figure 3c identify Nd oxalate decahydrate in a synthetic single-Nd experiment; this does not identify the mixed real-liquor precipitate or establish its phase purity. Single-salt Nd/La/Dy assays are separate from the processed ore.
Partial
Source:
lu2026_source_data
Fig.3a and 3b rows 17-28 and 34-45 reproduce the commercial and biological-A real-liquor curves; Fig. S1 to S8 rows 68-79 contain biological B. Fig.2 F11-F12 contain the two 10-day production titers, 38.78 and 40.27 g/L. The 42.70 g/L precipitation reagent is not one of those two values; its batch/time relationship to the displayed production series is not fully resolved and it is not substituted for the 39.53 g/L reported mean.
Context_only
Source:
lu2026
Figure 4 and the TEA/LCA methods describe modeled large-scale oxalic-acid production, including assumed co-location and electricity credits. These projections are not demonstrated industrial operation, a validated life-cycle result for this particular leachate train or evidence of field deployment.
Sources & References
-
lu2026: Lu J et al. (2026). Bio-based oxalic acid production in Issatchenkia orientalis enables sustainable rare earth recovery. Nature Communications 17:2193. DOI 10.1038/s41467-026-68957-5; original article, Figures 2-4 and Methods, especially Precipitation test, pages 7-9.
https://doi.org/10.1038/s41467-026-68957-5 (accessed 2026-10-12) -
lu2026_supplement: Lu et al. (2026), Supplementary Information, 28-page original PDF; Supplementary Methods 1-2, Table 1 (strain construction), Table 3 (single-Nd XRD assignment), Figures S6-S8 (production and separate precipitation arms).
https://media.springernature.com/original/springer-static/esm/art%3A10.1038%2Fs41467-026-68957-5/MediaObjects/41467_2026_68957_MOESM1_ESM.pdf (accessed 2026-10-12) -
lu2026_data1: Lu et al. (2026), Supplementary Data 1, original MOESM4 workbook; Raw Data and Volume Additions plus Analysis of OAP-O, OAP-A and OAP-B sheets, including initial volumes, sequential sampling, dilution corrections and calculated removal rows 66-77.
https://media.springernature.com/original/springer-static/esm/art%3A10.1038%2Fs41467-026-68957-5/MediaObjects/41467_2026_68957_MOESM4_ESM.xlsx (accessed 2026-10-12) -
lu2026_source_data: Lu et al. (2026), Source Data, original MOESM11 workbook; Fig.2, Fig.3a and 3b, Fig.3c, Fig.3d and Fig. S1 to S8 sheets.
https://media.springernature.com/original/springer-static/esm/art%3A10.1038%2Fs41467-026-68957-5/MediaObjects/41467_2026_68957_MOESM11_ESM.xlsx (accessed 2026-10-12) -
ncbi_kudriavzevii: NCBI Taxonomy 4909, Pichia kudriavzevii, species; Issatchenkia orientalis is listed as a heterotypic synonym. This species identifier does not identify engineered strain JL04 or authenticate the experimental stock.
https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=4909&mode=Info (accessed 2026-10-12)
Curation History
| Timestamp | Curator | Action | Summary |
|---|---|---|---|
2026-10-12T10:00:26Z |
codex (GPT-6) | CREATE | Added the chemically prepared allanite-derived liquor and engineered-yeast supernatant precipitation evidence, preserving source workbook discrepancies, impurity and mass-balance limits, separate assay arms and laboratory scope. |
Record source: data/records/allanite-leachate.yaml