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Title: Reduced Magnetism in Core–Shell Magnetite@MOF Composites

Abstract

Rare-earth elements (REEs) have significant commercial and military uses.1-3 However, REE extraction through conventional mining processes is expensive and feasible at only a few locations worldwide. Alternative methods are needed to produce REEs from more geographically disperse resources and in a cost effective, environmental friendly manner.4,5 Among various sources, geothermal brine, used for generating geothermal energy can possess attractive concentrations (ppb to ppm level) of REEs along with other dissolved metal ions.6 A system that can selectively trap the REEs using an existing geothermal power plant infrastructure would be an attractive additional revenue stream for the plant operator that could accelerate the development and deployment of geothermal plants in the United States and rest of the world.7,8 Here, we demonstrate a magnetic core-shell approach that can effectively extract REEs in their ionic form from aqueous solution with up to 99.99% removal efficiency. The shell, composed of thermally and chemically stable functionalized metal-organic framework (MOF), is grown over a synthesized Fe3O4 magnetic core. Magnetic susceptibility of the particles was found to decline significantly after in situ growth of a MOF shell, which resulted from oxidation of Fe2+ species of the magnetite (Fe3O4) to Fe3+ species (maghemite). The core-shell particles can bemore » completely removed from the mixture under an applied magnetic field, offering a practical, economic, and efficient REE-removal process.« less

Authors:
 [1]; ; ; ; ; ;  [2]; ; ;  [3]; ;  [2]; ORCiD logo
  1. Chemistry Department, Faculty of Science, Alexandria University, P.O. Box 426, Ibrahimia, Alexandria 21321, Egypt
  2. Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
  3. Department of Mechanical Engineering, University of Texas at El Paso, El Paso, Texas 79968, United States
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Geothermal Technologies Office (EE-4G)
OSTI Identifier:
1411894
Report Number(s):
PNNL-SA-122221
Journal ID: ISSN 1530-6984; GT0200000
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nano Letters; Journal Volume: 17; Journal Issue: 11
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; core shell nano particles; rare earth element extraction; MOFs

Citation Formats

Elsaidi, Sameh K., Sinnwell, Michael A., Banerjee, Debasis, Devaraj, Arun, Kukkadapu, Ravi K., Droubay, Timothy C., Nie, Zimin, Kovarik, Libor, Vijayakumar, Murugesan, Manandhar, Sandeep, Nandasiri, Manjula, McGrail, B. Peter, and Thallapally, Praveen K. Reduced Magnetism in Core–Shell Magnetite@MOF Composites. United States: N. p., 2017. Web. doi:10.1021/acs.nanolett.7b03451.
Elsaidi, Sameh K., Sinnwell, Michael A., Banerjee, Debasis, Devaraj, Arun, Kukkadapu, Ravi K., Droubay, Timothy C., Nie, Zimin, Kovarik, Libor, Vijayakumar, Murugesan, Manandhar, Sandeep, Nandasiri, Manjula, McGrail, B. Peter, & Thallapally, Praveen K. Reduced Magnetism in Core–Shell Magnetite@MOF Composites. United States. doi:10.1021/acs.nanolett.7b03451.
Elsaidi, Sameh K., Sinnwell, Michael A., Banerjee, Debasis, Devaraj, Arun, Kukkadapu, Ravi K., Droubay, Timothy C., Nie, Zimin, Kovarik, Libor, Vijayakumar, Murugesan, Manandhar, Sandeep, Nandasiri, Manjula, McGrail, B. Peter, and Thallapally, Praveen K. 2017. "Reduced Magnetism in Core–Shell Magnetite@MOF Composites". United States. doi:10.1021/acs.nanolett.7b03451.
@article{osti_1411894,
title = {Reduced Magnetism in Core–Shell Magnetite@MOF Composites},
author = {Elsaidi, Sameh K. and Sinnwell, Michael A. and Banerjee, Debasis and Devaraj, Arun and Kukkadapu, Ravi K. and Droubay, Timothy C. and Nie, Zimin and Kovarik, Libor and Vijayakumar, Murugesan and Manandhar, Sandeep and Nandasiri, Manjula and McGrail, B. Peter and Thallapally, Praveen K.},
abstractNote = {Rare-earth elements (REEs) have significant commercial and military uses.1-3 However, REE extraction through conventional mining processes is expensive and feasible at only a few locations worldwide. Alternative methods are needed to produce REEs from more geographically disperse resources and in a cost effective, environmental friendly manner.4,5 Among various sources, geothermal brine, used for generating geothermal energy can possess attractive concentrations (ppb to ppm level) of REEs along with other dissolved metal ions.6 A system that can selectively trap the REEs using an existing geothermal power plant infrastructure would be an attractive additional revenue stream for the plant operator that could accelerate the development and deployment of geothermal plants in the United States and rest of the world.7,8 Here, we demonstrate a magnetic core-shell approach that can effectively extract REEs in their ionic form from aqueous solution with up to 99.99% removal efficiency. The shell, composed of thermally and chemically stable functionalized metal-organic framework (MOF), is grown over a synthesized Fe3O4 magnetic core. Magnetic susceptibility of the particles was found to decline significantly after in situ growth of a MOF shell, which resulted from oxidation of Fe2+ species of the magnetite (Fe3O4) to Fe3+ species (maghemite). The core-shell particles can be completely removed from the mixture under an applied magnetic field, offering a practical, economic, and efficient REE-removal process.},
doi = {10.1021/acs.nanolett.7b03451},
journal = {Nano Letters},
number = 11,
volume = 17,
place = {United States},
year = 2017,
month =
}
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