TY - JOUR
T1 - Application of portable total-reflection X-ray fluorescence spectrometer to analysis of dysprosium in neodymium-iron-boron magnet
AU - Imashuku, Susumu
AU - Takahashi, Jun
AU - Kunimura, Shinsuke
AU - Wagatsuma, Kazuaki
N1 - Funding Information:
Financial support for the present study was provided by the 23rd ISIJ Research Promotion Grant and JSPS KAKENHI Grant Number 26709056.
Publisher Copyright:
© 2016 ISIJ.
PY - 2016
Y1 - 2016
N2 - Dysprosium (Dy) is expected to be recovered from end-of-life neodymium-iron-boron (NdFeB) magnets in the near future because of its worldwide shortage. Therefore, the rapid on-site elemental analysis of dysprosium in end-of-life NdFeB magnets is required. Here, we report a method of measuring the dysprosium composition in a NdFeB magnet on-site using a portable total-reflection X-ray fluorescence (TXRF) spectrometer. This method leads to drastic reduction of dysprosium loss caused by dissolving a NdFeB magnet because the portable TXRF spectrometer requires a small sample volume for measurement and its detection limit is as low as the ppb level. A NdFeB magnet was dissolved into hydrochloride acid and then iron in the solution was extracted using 4-methyl-2-pentanone (methyl isobutyl ketone: MIBK). Yttrium oxide (Y2O3) and a diluted standard solution of rubidium (Rb) were added to the solution as internal standards. We measured the X-ray intensities of dried residue of the solution using a portable TXRF spectrometer. Dy Lα line was clearly detected in the solution, whereas it overlapped with Fe Kα line in the solution before the MIBK extraction process. The dysprosium composition in the NdFeB magnet was determined from the measured intensities of Dy Lα, Y Kα, and Rb Kα, the relative sensitivities of dysprosium and yttrium to rubidium for the portable TXRF spectrometer, and the weights of the dissolved NdFeB magnet and yttrium oxide. The calculated dysprosium composition was in good agreement with that obtained by conventional ICP-AES.
AB - Dysprosium (Dy) is expected to be recovered from end-of-life neodymium-iron-boron (NdFeB) magnets in the near future because of its worldwide shortage. Therefore, the rapid on-site elemental analysis of dysprosium in end-of-life NdFeB magnets is required. Here, we report a method of measuring the dysprosium composition in a NdFeB magnet on-site using a portable total-reflection X-ray fluorescence (TXRF) spectrometer. This method leads to drastic reduction of dysprosium loss caused by dissolving a NdFeB magnet because the portable TXRF spectrometer requires a small sample volume for measurement and its detection limit is as low as the ppb level. A NdFeB magnet was dissolved into hydrochloride acid and then iron in the solution was extracted using 4-methyl-2-pentanone (methyl isobutyl ketone: MIBK). Yttrium oxide (Y2O3) and a diluted standard solution of rubidium (Rb) were added to the solution as internal standards. We measured the X-ray intensities of dried residue of the solution using a portable TXRF spectrometer. Dy Lα line was clearly detected in the solution, whereas it overlapped with Fe Kα line in the solution before the MIBK extraction process. The dysprosium composition in the NdFeB magnet was determined from the measured intensities of Dy Lα, Y Kα, and Rb Kα, the relative sensitivities of dysprosium and yttrium to rubidium for the portable TXRF spectrometer, and the weights of the dissolved NdFeB magnet and yttrium oxide. The calculated dysprosium composition was in good agreement with that obtained by conventional ICP-AES.
KW - Dysprosium
KW - Methyl isobutyl ketone
KW - Neodymium-iron-boron magnet
KW - On-site analysis
KW - Portable analyzer
KW - Total-reflection X-ray fluorescence
UR - http://www.scopus.com/inward/record.url?scp=85007228386&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85007228386&partnerID=8YFLogxK
U2 - 10.2355/isijinternational.ISIJINT-2016-349
DO - 10.2355/isijinternational.ISIJINT-2016-349
M3 - Article
AN - SCOPUS:85007228386
VL - 56
SP - 2224
EP - 2227
JO - Transactions of the Iron and Steel Institute of Japan
JF - Transactions of the Iron and Steel Institute of Japan
SN - 0915-1559
IS - 12
ER -