Adsorption of scandium and neodymium on biochar derived after low-temperature pyrolysis of sawdust
| Autor: | Georgios Alevizos, Konstantinos Komnitsas, Dimitra Zaharaki, Georgios Bartzas |
|---|---|
| Jazyk: | angličtina |
| Předmět: |
scandium
neodymium pyrolysis sawdust-derived biochar activated carbon adsorption Freundlich model lcsh:QE351-399.2 020209 energy Activated carbon Inorganic chemistry chemistry.chemical_element 02 engineering and technology 010501 environmental sciences 7. Clean energy 01 natural sciences Adsorption Biochar 0202 electrical engineering electronic engineering information engineering medicine Freundlich equation Scandium Point of zero charge 0105 earth and related environmental sciences Neodymium lcsh:Mineralogy Chemistry Sawdust-derived biochar Geology Geotechnical Engineering and Engineering Geology 13. Climate action visual_art visual_art.visual_art_medium Sawdust Pyrolysis medicine.drug |
| Zdroj: | Minerals Minerals, Vol 7, Iss 10, p 200 (2017) Minerals; Volume 7; Issue 10; Pages: 200 |
| Popis: | Research paper Summarization: The objective of this study was to investigate the adsorption of two rare earth elements (REEs), namely scandium (Sc) and neodymium (Nd), on biochar produced after low temperature pyrolysis (350◦C) of wood sawdust. The biochar was characterized with the use of several analytical techniques, namely X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric (TG) analysis, while the pH at point of zero charge (pHPZC) was also determined. The experimental conditions were: absorbent concentration 1–10 g L−1, REE concentration in solution 20 mg L−1, contact time for equilibrium 24 h, temperature 25◦C and stirring speed 350 rpm. The efficiency of biochar was compared to that of a commercial activated carbon. Geochemical modelling was carried out to determine speciation of Nd and Sc species in aqueous solutions using PHREEQC-3 equipped with the llnl database. The experimental results indicated the potential of low temperature produced biochar, even though inferior to that of activated carbon, to adsorb efficiently both REEs. The equilibrium adsorption data were very well fitted into the Freundlich isotherm model, while kinetic data suggested that the removal of both REEs follows the pseudo-second order kinetic reaction. Finally, the most probable adsorption mechanisms are discussed. Παρουσιάστηκε στο: Minerals |
| Databáze: | OpenAIRE |
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