The DOI matches its Crossref record.
Effect of pH on the Formation of Goethite and Hematite from Ferrihydrite
Abstract
Storage of ferrihydrite in aqueous suspensions at 24°C and pHs between 2.5 and 12 for as long as three years resulted in the formation of goethite and hematite. The proportions and crystallinity of these products varied widely with the pH. Maximum hematite was formed between pH 7 and 8, and maximum goethite at pH 4 and at pH 12. The crystallinity of both products, as indicated by X-ray powder diffraction line broadening and magnetic hyperfine field values and distribution widths, was poorer, the lower the proportion of the corresponding product in the mixture. The existence of two competitive formation processes is suggested: goethite is formed via solution, preferably from monovalent Fe(III) ions [Fe(OH)2+ and Fe(OH)4−], and hematite by internal rearrangement and dehydration within the ferrihydrite aggregates. This concept relates the proportions of goethite and hematite to the activity of the Fe(III) ion species in solution, and implies that conditions favorable for the formation of goethite are unfavorable for that of hematite and vice versa.
Overview
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Integrity signals
Registry
Cites
Statistics
Verification
Claims the paper makes
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
Citations
Cited by
Reactive iron in marine sediments
Canfield, D. E. (1989) · Geochimica et Cosmochimica Acta · doi:10.1016/0016-7037(89)90005-7 · Cited by 1,081
Occurrence and Constitution of Natural and Synthetic Ferrihydrite, a Widespread Iron Oxyhydroxide
Jambor, J. L., & Dutrizac, J. E. (1998) · Chemical Reviews · doi:10.1021/cr970105t · Cited by 916
Fredrickson, J. K., Zachara, J. M., Kennedy, D. W., Dong, H., Onstott, T. C., Hinman, N. W., & Li, S.-M. (1998) · Geochimica et Cosmochimica Acta · doi:10.1016/s0016-7037(98)00243-9 · Cited by 807
Zachara, J. M., Kukkadapu, R. K., Fredrickson, J. K., Gorby, Y. A., & Smith, S. C. (2002) · Geomicrobiology Journal · doi:10.1080/01490450252864271 · Cited by 364
Mo isotope fractionation during adsorption to Fe (oxyhydr)oxides
Goldberg, T., Archer, C., Vance, D., & Poulton, S. W. (2009) · Geochimica et Cosmochimica Acta · doi:10.1016/j.gca.2009.08.004 · Cited by 329
Metadata
- Authors
- Schwertmann, U., & Murad, E.
- Venue
- Clays and Clay Minerals
- Publisher
- Cambridge University Press (CUP)
- Published
- 1983-08
- Volume
- 31
- Issue
- 4
- Pages
- 277-284
- ISSN
- 0009-8604 (ISSN-L)
- 1552-8367
- OpenAlex
- W2159049505
- Cited by
- 749
- References
- 0
- FWCI
- 9.15
- Type
- journal article
- Language
- en
- Open access
- closed
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
How to cite
Cite CoChat for the checks on this page, and the paper for its own findings.
- This page
- CoChat. (2026). Citation check: Effect of pH on the Formation of Goethite and Hematite from Ferrihydrite. https://app.cochat.ai/papers/10.1346/ccmn.1983.0310405
- The paper
- Schwertmann, U., & Murad, E. (1983). Effect of pH on the Formation of Goethite and Hematite from Ferrihydrite. Clays and Clay Minerals. https://doi.org/10.1346/ccmn.1983.0310405
Data sources
Bibliographic data: Semantic Scholar, OpenAlex, Crossref.
Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.
