INVESTIGADORES
ESQUIVEL Marcelo Ricardo Oscar
artículos
Título:
Chlorination of samarium sesquioxide
Autor/es:
M.R. ESQUIVEL; A. BOHE; D. PASQUEVICH
Revista:
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
Editorial:
Elsevier
Referencias:
Lugar: Amsterdam; Año: 2005 vol. 170 p. 304 - 309
ISSN:
0924-0136
Resumen:
Samarium as either a metal or a compound has become very popular in the last years, mainly due to the applications of the metal or the
fluorides as precursors in permanent magnets, the use of the oxychlorides in optics and those of the oxide in many applications such as catalysis
and fuel cells. But samarium does not occur in nature as a metal due to its strong affinity for oxygen and sulfur. Therefore, its extraction from
minerals becomes difficult because of both the high stability of the oxides and the well known chemical similarities among them. Chlorination
using Cl2 (g) has been proposed as a useful method to separate Sm2O3 from the other lanthanide oxides. Despite its potential application as a
separation method, no kinetic data related to the interactions of this oxide and chlorine is known. This fact, related to the scientific field and
the possibility of using this method in extractive metallurgy at industrial scale aimed the elaboration of this work.
The chlorination of samarium sesquioxide with gaseous chlorine was studied by thermogravimetry. The effects of both the total gas flow
rate between 2.1 and 7.9 l h−1 (NTP) and temperature between 200 and 950 ◦C on the reaction rate were analyzed. Apparent activation energy
values of 2040, 129±1 and 12±7 kJmol−1 corresponding to the 200270, 270350 and 350950 ◦C temperature ranges were found. SmOCl
(s) and O2 (g) were the reaction products. Solids involved on the reaction were analyzed by X-ray diffraction (XRD) and energy dispersive
spectroscopy (EDS). The microstructure was observed by scanning electron microscopy (SEM).
2 (g) has been proposed as a useful method to separate Sm2O3 from the other lanthanide oxides. Despite its potential application as a
separation method, no kinetic data related to the interactions of this oxide and chlorine is known. This fact, related to the scientific field and
the possibility of using this method in extractive metallurgy at industrial scale aimed the elaboration of this work.
The chlorination of samarium sesquioxide with gaseous chlorine was studied by thermogravimetry. The effects of both the total gas flow
rate between 2.1 and 7.9 l h−1 (NTP) and temperature between 200 and 950 ◦C on the reaction rate were analyzed. Apparent activation energy
values of 2040, 129±1 and 12±7 kJmol−1 corresponding to the 200270, 270350 and 350950 ◦C temperature ranges were found. SmOCl
(s) and O2 (g) were the reaction products. Solids involved on the reaction were analyzed by X-ray diffraction (XRD) and energy dispersive
spectroscopy (EDS). The microstructure was observed by scanning electron microscopy (SEM).
−1 (NTP) and temperature between 200 and 950 ◦C on the reaction rate were analyzed. Apparent activation energy
values of 2040, 129±1 and 12±7 kJmol−1 corresponding to the 200270, 270350 and 350950 ◦C temperature ranges were found. SmOCl
(s) and O2 (g) were the reaction products. Solids involved on the reaction were analyzed by X-ray diffraction (XRD) and energy dispersive
spectroscopy (EDS). The microstructure was observed by scanning electron microscopy (SEM).
±1 and 12±7 kJmol−1 corresponding to the 200270, 270350 and 350950 ◦C temperature ranges were found. SmOCl
(s) and O2 (g) were the reaction products. Solids involved on the reaction were analyzed by X-ray diffraction (XRD) and energy dispersive
spectroscopy (EDS). The microstructure was observed by scanning electron microscopy (SEM).
2 (g) were the reaction products. Solids involved on the reaction were analyzed by X-ray diffraction (XRD) and energy dispersive
spectroscopy (EDS). The microstructure was observed by scanning electron microscopy (SEM).