Hydrothermal decomposition of industrial jarosite in alkaline media: The rate determining step of the process kinetics
This work examines the role of NaOH and Ca(OH)2 on the hydrothermal decomposition of industrial jarosite deposited by a Mexican company in a tailings dam. The industrial jarosite is mainly composed by natrojarosite and contains 150 g Ag/t, showing a narrow particle size distribution, as rev...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
University of Belgrade, Technical Faculty, Bor
2016-01-01
|
| Series: | Journal of Mining and Metallurgy. Section B: Metallurgy |
| Subjects: | |
| Online Access: | http://www.doiserbia.nb.rs/img/doi/1450-5339/2016/1450-53391600016G.pdf |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1832570044759932928 |
|---|---|
| author | González-Ibarra A.A. Nava-Alonso F. Fuentes-Aceituno J.C. Uribe-Salas A. |
| author_facet | González-Ibarra A.A. Nava-Alonso F. Fuentes-Aceituno J.C. Uribe-Salas A. |
| author_sort | González-Ibarra A.A. |
| collection | DOAJ |
| description | This work examines the role of NaOH and Ca(OH)2 on the hydrothermal
decomposition of industrial jarosite deposited by a Mexican company in a
tailings dam. The industrial jarosite is mainly composed by natrojarosite and
contains 150 g Ag/t, showing a narrow particle size distribution, as revealed
by XRD, fire assay, SEM-EDS and laser-diffraction analysis. The effect of the
pH, when using NaOH or Ca(OH)2 as alkalinizing agent was studied by carrying
out decomposition experiments at different pH values and 60°C in a
homogeneous size particle system (pH = 8, 9, 10 and 11) and in a
heterogeneous size particle system (pH = 11). Also, the kinetic study of the
process and the controlling step of the decomposition reaction when NaOH and
Ca(OH)2 are used was determined by fitting the data obtained to the shrinking
core model for spherical particles of constant size. These results, supported
by chemical (EDS), morphological (SEM) and mapping of elements (EDS) analysis
of a partially reacted jarosite particle allowed to conclude that when NaOH
is used, the process kinetics is controlled by the chemical reaction and when
Ca(OH)2 is used, the rate determining step is changed to a diffusion control
through a layer of solid products. |
| format | Article |
| id | doaj-art-034b7c28786e4f7cb75fbdcef8acb6cb |
| institution | Kabale University |
| issn | 1450-5339 2217-7175 |
| language | English |
| publishDate | 2016-01-01 |
| publisher | University of Belgrade, Technical Faculty, Bor |
| record_format | Article |
| series | Journal of Mining and Metallurgy. Section B: Metallurgy |
| spelling | doaj-art-034b7c28786e4f7cb75fbdcef8acb6cb2025-02-02T17:29:56ZengUniversity of Belgrade, Technical Faculty, BorJournal of Mining and Metallurgy. Section B: Metallurgy1450-53392217-71752016-01-0152213514210.2298/JMMB150430016G1450-53391600016GHydrothermal decomposition of industrial jarosite in alkaline media: The rate determining step of the process kineticsGonzález-Ibarra A.A.0Nava-Alonso F.1Fuentes-Aceituno J.C.2Uribe-Salas A.3CINVESTAV Unidad Saltillo, Ramos Arizpe, MexicoCINVESTAV Unidad Saltillo, Ramos Arizpe, Mexico + Laval University, Department of Mining, Metallurgical and Materials Engineering, Quebec, CanadaCINVESTAV Unidad Saltillo, Ramos Arizpe, MexicoCINVESTAV Unidad Saltillo, Ramos Arizpe, MexicoThis work examines the role of NaOH and Ca(OH)2 on the hydrothermal decomposition of industrial jarosite deposited by a Mexican company in a tailings dam. The industrial jarosite is mainly composed by natrojarosite and contains 150 g Ag/t, showing a narrow particle size distribution, as revealed by XRD, fire assay, SEM-EDS and laser-diffraction analysis. The effect of the pH, when using NaOH or Ca(OH)2 as alkalinizing agent was studied by carrying out decomposition experiments at different pH values and 60°C in a homogeneous size particle system (pH = 8, 9, 10 and 11) and in a heterogeneous size particle system (pH = 11). Also, the kinetic study of the process and the controlling step of the decomposition reaction when NaOH and Ca(OH)2 are used was determined by fitting the data obtained to the shrinking core model for spherical particles of constant size. These results, supported by chemical (EDS), morphological (SEM) and mapping of elements (EDS) analysis of a partially reacted jarosite particle allowed to conclude that when NaOH is used, the process kinetics is controlled by the chemical reaction and when Ca(OH)2 is used, the rate determining step is changed to a diffusion control through a layer of solid products.http://www.doiserbia.nb.rs/img/doi/1450-5339/2016/1450-53391600016G.pdfhydrothermal decompositionpHshrinking core model |
| spellingShingle | González-Ibarra A.A. Nava-Alonso F. Fuentes-Aceituno J.C. Uribe-Salas A. Hydrothermal decomposition of industrial jarosite in alkaline media: The rate determining step of the process kinetics Journal of Mining and Metallurgy. Section B: Metallurgy hydrothermal decomposition pH shrinking core model |
| title | Hydrothermal decomposition of industrial jarosite in alkaline media: The rate determining step of the process kinetics |
| title_full | Hydrothermal decomposition of industrial jarosite in alkaline media: The rate determining step of the process kinetics |
| title_fullStr | Hydrothermal decomposition of industrial jarosite in alkaline media: The rate determining step of the process kinetics |
| title_full_unstemmed | Hydrothermal decomposition of industrial jarosite in alkaline media: The rate determining step of the process kinetics |
| title_short | Hydrothermal decomposition of industrial jarosite in alkaline media: The rate determining step of the process kinetics |
| title_sort | hydrothermal decomposition of industrial jarosite in alkaline media the rate determining step of the process kinetics |
| topic | hydrothermal decomposition pH shrinking core model |
| url | http://www.doiserbia.nb.rs/img/doi/1450-5339/2016/1450-53391600016G.pdf |
| work_keys_str_mv | AT gonzalezibarraaa hydrothermaldecompositionofindustrialjarositeinalkalinemediatheratedeterminingstepoftheprocesskinetics AT navaalonsof hydrothermaldecompositionofindustrialjarositeinalkalinemediatheratedeterminingstepoftheprocesskinetics AT fuentesaceitunojc hydrothermaldecompositionofindustrialjarositeinalkalinemediatheratedeterminingstepoftheprocesskinetics AT uribesalasa hydrothermaldecompositionofindustrialjarositeinalkalinemediatheratedeterminingstepoftheprocesskinetics |