Oxidized zinc ore primary resource
Natural oxidized zinc ore, represented here by a mixed, Fe-rich sample from Kozan-Horzum, Adana, Türkiye. The study calls it smithsonite ore, but its XRD pattern assigns smithsonite, hemimorphite and several gangue phases. This heterogeneous geological feed is distinct from pure smithsonite, sphalerite concentrate, elemental zinc, a specified traded product and a processing waste. Its composition and experimental results do not characterize all oxidized zinc ores. No constituent-element criticality or mineral-species identifier is inherited.
Microbial & Biochemical Mechanisms (1)
Culture-associated dissolution of zinc and iron from mixed ore
bioleaching
Microbial
Inoculated laboratory flasks were reported to release Zn and Fe into acidic liquor. The culture is identified in the paper as Acidithiobacillus ferrooxidans DSM 583. This is a source-reported culture-associated dissolution result; the published controls do not quantify the microbial contribution relative to chemical dissolution. Proposed iron cycling and ferric attack are interpretations, not demonstrated mineral-specific reactions or enzyme mechanisms.
Experimental Context & Analytical Limits:
Methods pp1068-1069 describe oven drying, crushing below 1 cm, ball milling and sieving below 75 micrometres. Table 1 lists XRF oxide-composition entries without an explicit unit, so no elemental concentration or pure-phase abundance is inferred from them. The reported Fe-free 9K medium contained 0.4 g/L ammonium sulfate, 0.4 g/L magnesium sulfate heptahydrate, 0.2 g/L potassium dihydrogen phosphate and 0.1 g/L potassium chloride. Sulfuric acid adjusted initial pH to 1.8-2; the flask preparation specifies 15% dosing acid. Each 250-mL flask had 100 mL working liquid, comprising 90 mL medium and 10 mL starter culture, at 150 rpm and 25 +/- 5 degrees C. Medium was autoclaved at 121 degrees C for 15 minutes; ore sterilization is not specified. Culture activation, an energy donor during preculture and starter-medium carryover are unresolved. The nine reported design combinations used solid ratios of 10, 15 and 20% and times of 6, 12 and 18 days; the percentage basis is not explicitly w/v or w/w and is not converted to g/L. Every six days, 5 mL was withdrawn and filtered at 0.2 micrometres for Zn, Fe and Pb analysis by atomic absorption spectrometry. Cell counts used a Petroff-Hausser slide. Methods says triplicate on p1068 but duplicate on p1069; endpoint tables provide neither raw replicates nor standard deviations. The paper and DSMZ catalogue use A. ferrooxidans, whereas BacDive links a genome labeled A. ferridurans DSM 583. The accession and naming conflict are retained without a definitive species CURIE. These are laboratory assays, with no isolated metal product or demonstrated pilot or industrial deployment.
Methods pp1068-1069 describe oven drying, crushing below 1 cm, ball milling and sieving below 75 micrometres. Table 1 lists XRF oxide-composition entries without an explicit unit, so no elemental concentration or pure-phase abundance is inferred from them. The reported Fe-free 9K medium contained 0.4 g/L ammonium sulfate, 0.4 g/L magnesium sulfate heptahydrate, 0.2 g/L potassium dihydrogen phosphate and 0.1 g/L potassium chloride. Sulfuric acid adjusted initial pH to 1.8-2; the flask preparation specifies 15% dosing acid. Each 250-mL flask had 100 mL working liquid, comprising 90 mL medium and 10 mL starter culture, at 150 rpm and 25 +/- 5 degrees C. Medium was autoclaved at 121 degrees C for 15 minutes; ore sterilization is not specified. Culture activation, an energy donor during preculture and starter-medium carryover are unresolved. The nine reported design combinations used solid ratios of 10, 15 and 20% and times of 6, 12 and 18 days; the percentage basis is not explicitly w/v or w/w and is not converted to g/L. Every six days, 5 mL was withdrawn and filtered at 0.2 micrometres for Zn, Fe and Pb analysis by atomic absorption spectrometry. Cell counts used a Petroff-Hausser slide. Methods says triplicate on p1068 but duplicate on p1069; endpoint tables provide neither raw replicates nor standard deviations. The paper and DSMZ catalogue use A. ferrooxidans, whereas BacDive links a genome labeled A. ferridurans DSM 583. The accession and naming conflict are retained without a definitive species CURIE. These are laboratory assays, with no isolated metal product or demonstrated pilot or industrial deployment.
Curated Evidence Points:
Support
Source:
demirci_2025
Table 3 row 2 reports the highest tested solution-release percentages, 54.70% Zn and 63.14% Fe, at the stated 10% solid ratio and 12 days. At the same loading, row 3 reports lower values at 18 days, 44.11% Zn and 51.45% Fe. These are the author's reported aqueous dissolution metrics, not independently reconciled yields or additional measurements from the fitted contour plots. The p1070 discussion reports Pb was not solubilized, but gives no Pb concentration or detection limit; no numerical zero or confirmed PbSO4/PbCO3 product is asserted.
Partial
Source:
demirci_2025
Figures 1-3 show pH, redox and cell-count trajectories; abiotic controls are displayed for pH and redox. Although the text says controls were run at every loading, it supplies no numerical abiotic Zn/Fe dissolution series from which to calculate microbial enhancement. The initial external acid, incompletely specified inoculum conditioning and lack of a matched-pH dissolution comparison limit causality. No direct Fe(II)/Fe(III) or sulfur oxidation measurements establish the proposed iron cycle or the source of energy in the nominally Fe-free medium. Cell counts and bulk redox changes do not establish ferric attack on ZnCO3.
Partial
Source:
demirci_2025
Equation 2 labels liquor volume in mL and dissolved concentration in mg/L without displaying a volume conversion. Correction for serial 5-mL withdrawals, replacement liquid and cumulative metal inventories is not documented. The feed concentration denominator cannot be reconstructed from the unit-unspecified XRF oxide table. Reported percentages therefore remain qualified source values; no repaired balance or exact concentration observations are added. Table 4 is captioned as S/N-based ANOVA, but its sums of squares approximately match calculations from Table 3's raw percentage outcomes, not its printed S/N values. Replication and statistical processing cannot be resolved from the paper. Figures 5-7 are derived summaries and contour estimates, not independent confirmation of an optimum, significance or general process yield.
Partial
Source:
demirci_2025
Figure 4 labels multiple minerals in vertically offset pre/post patterns, including both smithsonite and hemimorphite. It provides no quantitative phase balance, specified post-leach treatment condition or abiotic residue comparison. Reduced peak intensities do not assign all dissolved Zn to smithsonite, and absence of new diffraction peaks does not exclude amorphous or trace precipitates. Proposed passivation, mass-transfer inhibition and lead-phase precipitation are interpretations without direct tests here. The conclusions call for pilot and industrial feasibility work; environmental and economic advantages were not measured.
Context_only
Source:
dsm583_catalogue
The current collection catalogue agrees with the paper's A. ferrooxidans DSM 583 name. It does not independently genotype or verify the culture used in the ore experiment.
Partial
Source:
bacdive111
The strain entry's front matter and linked genome use different species names. This limits a definitive species mapping for the reported DSM 583 stock; neither a species identifier nor genome identity is assigned to the experimental culture.
Sources & References
-
demirci_2025: Demirci S (2025). Bioleaching of Oxidized Zinc Ore Using Acidithiobacillus Ferrooxidans with Taguchi Approach. Dicle University Journal of Engineering 16(4):1067-1075. DOI 10.24012/dumf.1748240. Complete official nine-page PDF; methods pp1068-1069, Tables 1-4, Figures 1-7 and conclusions pp1072-1073 inspected. The printed DOI prefix 0.24012 is erroneous; publisher and Crossref resolve 10.24012.
https://doi.org/10.24012/dumf.1748240 (accessed 2026-10-11) -
demirci_2025_registration: Crossref registration for 10.24012/dumf.1748240, confirming title, Seda Demirci authorship and publication date 30 December 2025.
https://api.crossref.org/works/10.24012/dumf.1748240 (accessed 2026-10-11) -
dsm583_catalogue: DSMZ culture catalogue, DSM 583, displayed as Acidithiobacillus ferrooxidans. Collection-to-name context, not authentication of the experimental stock.
https://www.dsmz.de/collection/catalogue/details/culture/dsm-583 (accessed 2026-10-11) -
bacdive111: BacDive strain 111, DSM 583. Front matter displays Acidithiobacillus ferrooxidans while the linked genome GCA_018854535 is labeled Acidithiobacillus ferridurans DSM 583.
https://bacdive.dsmz.de/strain/111 (accessed 2026-10-11)
Curation History
| Timestamp | Curator | Action | Summary |
|---|---|---|---|
2026-10-11T17:43:43.212961+00:00 |
Codex (GPT-6; Codex) | CREATE | Added a source-defined mixed oxidized-zinc ore identity and qualified culture-associated aqueous Zn/Fe dissolution. Preserved strain-name ambiguity, qualitative Pb non-solubilization, incomplete controls, replication and unit conflicts, unresolved inventory accounting and the distinction between reported endpoints and derived analyses. |
Record source: data/records/oxidized-zinc-ore.yaml