Fe(II)-induced transformation from ferrihydrite to lepidocrocite and goethite
- School of Chemistry and material Science, Hebei Normal University, Shijiazhuang 050016 (China)
- Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001 (China)
The transformation of Fe(II)-adsorbed ferrihydrite was studied. Data tracking the formation of products as a function of pH, temperature and time is presented. The results indicate that trace of Fe(II) adsorbed on ferrihydrite can accelerate its transformation obviously. The products are lepidocrocite and/or goethite and/or hematite, which is different from those without Fe(II). That is, Fe(II) not only accelerates the transformation of ferrihydrite but also leads to the formation of lepidocrocite by a new path. The behavior of Fe(II) is shown in two aspects-catalytic dissolution-reprecipitation and catalytic solid-state transformation. The results indicate that a high temperature and a high pH(in the range from 5 to 9) are favorable to solid-state transformation and the formation of hematite, while a low temperature and a low pH are favorable to dissolution-reprecipitation mechanism and the formation of lepidocrocite. Special attentions were given to the formation mechanism of lepidocrocite and goethite. - Graphical abstract: Fe(II)-adsorbed ferrihydrite can rapidly transform into lepidocrocite or/and goethite or/and hematite. Which product dominates depends on the transformation conditions of ferrihydrite such as temperature, pH, reaction time, etc. In the current system, there exist two transformation mechanisms. One is dissolution/reprecipitation and the other is solid-state transformation. The transformation mechanisms from Fe(II)-adsorbed ferrihydrite to lepidocrocite and goethite were investigated.
- OSTI ID:
- 21015882
- Journal Information:
- Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 7 Vol. 180; ISSN 0022-4596; ISSN JSSCBI
- Country of Publication:
- United States
- Language:
- English
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