Tungsten solubility and speciation in hydrothermal solutions revealed by in situ X-ray absorption spectroscopy
<p>Tungsten (W) concentrations in fluids in equilibrium with crystalline tungsten oxide are used to determine thermodynamic parameters for W solubility and W species in hydrothermal fluids. The solubility data were measured in situ at high pressures and temperatures using X-ray absorption. X-r...
Saved in:
| Main Authors: | , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2025-02-01
|
| Series: | European Journal of Mineralogy |
| Online Access: | https://ejm.copernicus.org/articles/37/111/2025/ejm-37-111-2025.pdf |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849765396374093824 |
|---|---|
| author | M. Borchert M. Borchert M. A. Kokh M. A. Kokh M. Louvel M. Louvel E. F. Bazarkina E. F. Bazarkina A. Loges E. Welter D. Testemale R. Al Abed S. Klemme M. Wilke |
| author_facet | M. Borchert M. Borchert M. A. Kokh M. A. Kokh M. Louvel M. Louvel E. F. Bazarkina E. F. Bazarkina A. Loges E. Welter D. Testemale R. Al Abed S. Klemme M. Wilke |
| author_sort | M. Borchert |
| collection | DOAJ |
| description | <p>Tungsten (W) concentrations in fluids in equilibrium with crystalline tungsten oxide are used to determine thermodynamic parameters for W solubility and W species in hydrothermal fluids. The solubility data were measured in situ at high pressures and temperatures using X-ray absorption. X-ray spectroscopic data measured in situ – with X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) – were applied to characterize the symmetry and the type of atoms of the first coordination shell of W aqueous complexes present in the fluid at given temperatures and pressures. Experiments were performed at up to 400 °C and at pressures of 40, 50 and 60 MPa. With this dataset, we were able to improve constraints for the already-suggested fluid species WO<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M1" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mrow><mn mathvariant="normal">2</mn><mo>-</mo></mrow></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="13pt" height="17pt" class="svg-formula" dspmath="mathimg" md5hash="fa6a3d1c655e3a1a9feb31b6a98317a5"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00001.svg" width="13pt" height="17pt" src="ejm-37-111-2025-ie00001.png"/></svg:svg></span></span>, HWO<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M2" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mo>-</mo></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="9pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="b6eae26b160dad06c5030a466620317b"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00002.svg" width="9pt" height="16pt" src="ejm-37-111-2025-ie00002.png"/></svg:svg></span></span>, H<span class="inline-formula"><sub>2</sub></span>WO<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mn mathvariant="normal">0</mn></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="7pt" height="17pt" class="svg-formula" dspmath="mathimg" md5hash="f65cbc9bcc2e7c68d9dab1c6f1426119"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00003.svg" width="7pt" height="17pt" src="ejm-37-111-2025-ie00003.png"/></svg:svg></span></span>, NaWO<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M5" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mo>-</mo></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="9pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="848b33a44e3b4138e639b80482e1fbb7"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00004.svg" width="9pt" height="16pt" src="ejm-37-111-2025-ie00004.png"/></svg:svg></span></span> and NaHWO<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M6" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mn mathvariant="normal">0</mn></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="7pt" height="17pt" class="svg-formula" dspmath="mathimg" md5hash="957fb3d072546ec621eb58df8977ed94"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00005.svg" width="7pt" height="17pt" src="ejm-37-111-2025-ie00005.png"/></svg:svg></span></span>. Further, we were able to introduce the H<span class="inline-formula"><sub>3</sub></span>WO<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M8" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mo>+</mo></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="a9b2fdba183dceff94210c316afa95ef"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00006.svg" width="8pt" height="15pt" src="ejm-37-111-2025-ie00006.png"/></svg:svg></span></span> species that is found to be dominant in acidic fluids. No evidence was found for W species involving Cl<span class="inline-formula"><sup>−</sup></span> as a ligand. The ionic W species found in the fluid are characterized by a tetrahedral complex at alkaline conditions. In neutral to acidic conditions, W complexes with distorted octahedral symmetry are formed. These complexes may be polymerized at temperatures <span class="inline-formula">≤200</span> °C and W concentrations <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M11" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>></mo><msup><mn mathvariant="normal">10</mn><mrow><mo>-</mo><mn mathvariant="normal">3</mn></mrow></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="35pt" height="13pt" class="svg-formula" dspmath="mathimg" md5hash="8cf1e8ae621f2c097aac89a396bbafbf"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00007.svg" width="35pt" height="13pt" src="ejm-37-111-2025-ie00007.png"/></svg:svg></span></span> mol kg<span class="inline-formula"><sup>−1</sup></span> H<span class="inline-formula"><sub>2</sub></span>O. X-ray spectroscopy as well as thermodynamic modeling suggests that polytungstate species are not relevant at equilibrium concentrations found in the solubility experiments of this study (<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M14" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>≤</mo><msup><mn mathvariant="normal">10</mn><mrow><mo>-</mo><mn mathvariant="normal">3</mn></mrow></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="35pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="d85bcf19a81ce57d4de382d38959b170"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00008.svg" width="35pt" height="14pt" src="ejm-37-111-2025-ie00008.png"/></svg:svg></span></span> mol W kg<span class="inline-formula"><sup>−1</sup></span> H<span class="inline-formula"><sub>2</sub></span>O in equilibrium with tungsten oxide) or at concentrations reported for natural systems. Using the thermodynamic properties of the species mentioned above, in situ data on the solubility of scheelite can be successfully described. Thermodynamic modeling shows that scheelite solubility and wolframite solubility strongly increase with increasing salinity, especially up to 1 <i>m</i> NaCl (<i>m</i> denotes molality), and vary with pH, which is consistent with earlier reports. Overall, this study provides improved thermodynamic properties for a set of W fluid species that cover a wide range of fluid compositions, which is necessary for understanding the complex processes of W enrichment and mineralization in hydrothermal systems.</p> |
| format | Article |
| id | doaj-art-3d1895e9dc844883bffbd6dd8318d2a8 |
| institution | DOAJ |
| issn | 0935-1221 1617-4011 |
| language | English |
| publishDate | 2025-02-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | European Journal of Mineralogy |
| spelling | doaj-art-3d1895e9dc844883bffbd6dd8318d2a82025-08-20T03:04:53ZengCopernicus PublicationsEuropean Journal of Mineralogy0935-12211617-40112025-02-013711113010.5194/ejm-37-111-2025Tungsten solubility and speciation in hydrothermal solutions revealed by in situ X-ray absorption spectroscopyM. Borchert0M. Borchert1M. A. Kokh2M. A. Kokh3M. Louvel4M. Louvel5E. F. Bazarkina6E. F. Bazarkina7A. Loges8E. Welter9D. Testemale10R. Al Abed11S. Klemme12M. Wilke13Institut für Mineralogie, Universität Münster, Corrensstrasse 24, 48149 Münster, GermanyDeutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, GermanyInstitut für Mineralogie, Universität Münster, Corrensstrasse 24, 48149 Münster, GermanyInstitut für Geowissenschaften, Universität Potsdam, Karl-Liebknecht-Str. 24–25, 14476 Potsdam, GermanyInstitut für Mineralogie, Universität Münster, Corrensstrasse 24, 48149 Münster, GermanyInstitut des Sciences de la Terre d'Orléans, CNRS–BRGM–Univ. Orléans, 1A rue de la Ferollerie, 45100 Orléans, FranceInstitute of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), P.O. Box 510119, 01314 Dresden, GermanyThe Rossendorf Beamline, European Synchrotron Radiation Facility (ESRF), CS40220, 38043 Grenoble CEDEX 9, FranceInstitut für Geologische Wissenschaften, Freie Universität Berlin, Malteserstr. 74–100, 12249 Berlin, GermanyDeutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, GermanyUniversité Grenoble Alpes, CNRS, Institut Néel, 38000 Grenoble, FranceInstitut für Geowissenschaften, Universität Potsdam, Karl-Liebknecht-Str. 24–25, 14476 Potsdam, GermanyInstitut für Mineralogie, Universität Münster, Corrensstrasse 24, 48149 Münster, GermanyInstitut für Geowissenschaften, Universität Potsdam, Karl-Liebknecht-Str. 24–25, 14476 Potsdam, Germany<p>Tungsten (W) concentrations in fluids in equilibrium with crystalline tungsten oxide are used to determine thermodynamic parameters for W solubility and W species in hydrothermal fluids. The solubility data were measured in situ at high pressures and temperatures using X-ray absorption. X-ray spectroscopic data measured in situ – with X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) – were applied to characterize the symmetry and the type of atoms of the first coordination shell of W aqueous complexes present in the fluid at given temperatures and pressures. Experiments were performed at up to 400 °C and at pressures of 40, 50 and 60 MPa. With this dataset, we were able to improve constraints for the already-suggested fluid species WO<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M1" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mrow><mn mathvariant="normal">2</mn><mo>-</mo></mrow></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="13pt" height="17pt" class="svg-formula" dspmath="mathimg" md5hash="fa6a3d1c655e3a1a9feb31b6a98317a5"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00001.svg" width="13pt" height="17pt" src="ejm-37-111-2025-ie00001.png"/></svg:svg></span></span>, HWO<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M2" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mo>-</mo></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="9pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="b6eae26b160dad06c5030a466620317b"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00002.svg" width="9pt" height="16pt" src="ejm-37-111-2025-ie00002.png"/></svg:svg></span></span>, H<span class="inline-formula"><sub>2</sub></span>WO<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mn mathvariant="normal">0</mn></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="7pt" height="17pt" class="svg-formula" dspmath="mathimg" md5hash="f65cbc9bcc2e7c68d9dab1c6f1426119"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00003.svg" width="7pt" height="17pt" src="ejm-37-111-2025-ie00003.png"/></svg:svg></span></span>, NaWO<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M5" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mo>-</mo></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="9pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="848b33a44e3b4138e639b80482e1fbb7"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00004.svg" width="9pt" height="16pt" src="ejm-37-111-2025-ie00004.png"/></svg:svg></span></span> and NaHWO<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M6" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mn mathvariant="normal">0</mn></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="7pt" height="17pt" class="svg-formula" dspmath="mathimg" md5hash="957fb3d072546ec621eb58df8977ed94"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00005.svg" width="7pt" height="17pt" src="ejm-37-111-2025-ie00005.png"/></svg:svg></span></span>. Further, we were able to introduce the H<span class="inline-formula"><sub>3</sub></span>WO<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M8" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi/><mn mathvariant="normal">4</mn><mo>+</mo></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="a9b2fdba183dceff94210c316afa95ef"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00006.svg" width="8pt" height="15pt" src="ejm-37-111-2025-ie00006.png"/></svg:svg></span></span> species that is found to be dominant in acidic fluids. No evidence was found for W species involving Cl<span class="inline-formula"><sup>−</sup></span> as a ligand. The ionic W species found in the fluid are characterized by a tetrahedral complex at alkaline conditions. In neutral to acidic conditions, W complexes with distorted octahedral symmetry are formed. These complexes may be polymerized at temperatures <span class="inline-formula">≤200</span> °C and W concentrations <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M11" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>></mo><msup><mn mathvariant="normal">10</mn><mrow><mo>-</mo><mn mathvariant="normal">3</mn></mrow></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="35pt" height="13pt" class="svg-formula" dspmath="mathimg" md5hash="8cf1e8ae621f2c097aac89a396bbafbf"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00007.svg" width="35pt" height="13pt" src="ejm-37-111-2025-ie00007.png"/></svg:svg></span></span> mol kg<span class="inline-formula"><sup>−1</sup></span> H<span class="inline-formula"><sub>2</sub></span>O. X-ray spectroscopy as well as thermodynamic modeling suggests that polytungstate species are not relevant at equilibrium concentrations found in the solubility experiments of this study (<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M14" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>≤</mo><msup><mn mathvariant="normal">10</mn><mrow><mo>-</mo><mn mathvariant="normal">3</mn></mrow></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="35pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="d85bcf19a81ce57d4de382d38959b170"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-37-111-2025-ie00008.svg" width="35pt" height="14pt" src="ejm-37-111-2025-ie00008.png"/></svg:svg></span></span> mol W kg<span class="inline-formula"><sup>−1</sup></span> H<span class="inline-formula"><sub>2</sub></span>O in equilibrium with tungsten oxide) or at concentrations reported for natural systems. Using the thermodynamic properties of the species mentioned above, in situ data on the solubility of scheelite can be successfully described. Thermodynamic modeling shows that scheelite solubility and wolframite solubility strongly increase with increasing salinity, especially up to 1 <i>m</i> NaCl (<i>m</i> denotes molality), and vary with pH, which is consistent with earlier reports. Overall, this study provides improved thermodynamic properties for a set of W fluid species that cover a wide range of fluid compositions, which is necessary for understanding the complex processes of W enrichment and mineralization in hydrothermal systems.</p>https://ejm.copernicus.org/articles/37/111/2025/ejm-37-111-2025.pdf |
| spellingShingle | M. Borchert M. Borchert M. A. Kokh M. A. Kokh M. Louvel M. Louvel E. F. Bazarkina E. F. Bazarkina A. Loges E. Welter D. Testemale R. Al Abed S. Klemme M. Wilke Tungsten solubility and speciation in hydrothermal solutions revealed by in situ X-ray absorption spectroscopy European Journal of Mineralogy |
| title | Tungsten solubility and speciation in hydrothermal solutions revealed by in situ X-ray absorption spectroscopy |
| title_full | Tungsten solubility and speciation in hydrothermal solutions revealed by in situ X-ray absorption spectroscopy |
| title_fullStr | Tungsten solubility and speciation in hydrothermal solutions revealed by in situ X-ray absorption spectroscopy |
| title_full_unstemmed | Tungsten solubility and speciation in hydrothermal solutions revealed by in situ X-ray absorption spectroscopy |
| title_short | Tungsten solubility and speciation in hydrothermal solutions revealed by in situ X-ray absorption spectroscopy |
| title_sort | tungsten solubility and speciation in hydrothermal solutions revealed by in situ x ray absorption spectroscopy |
| url | https://ejm.copernicus.org/articles/37/111/2025/ejm-37-111-2025.pdf |
| work_keys_str_mv | AT mborchert tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy AT mborchert tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy AT makokh tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy AT makokh tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy AT mlouvel tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy AT mlouvel tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy AT efbazarkina tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy AT efbazarkina tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy AT aloges tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy AT ewelter tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy AT dtestemale tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy AT ralabed tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy AT sklemme tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy AT mwilke tungstensolubilityandspeciationinhydrothermalsolutionsrevealedbyinsituxrayabsorptionspectroscopy |