INVESTIGADORES
BOHE Ana Ester
artículos
Título:
The kinetics of the chlorination of yttrium oxide
Autor/es:
JUAN PABLO GAVIRÍA; ANA ESTER BOHÉ
Revista:
METALLURGICAL AND MATERIALS TRANSACTIONS B
Editorial:
The Minerals, Metals & Material Society and ASM Internacional 09 D.E. ,Laughlin
Referencias:
Lugar: D.E. Laughlin; Año: 2009 vol. 40 p. 45 - 53
ISSN:
0360-2141
Resumen:
The chlorination kinetics of Y2O3 with chlorine to produce YOCl was studied by thermogravimetry
over a temperature range from 575 C to 975 C. The influence of convective mass
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
over a temperature range from 575 C to 975 C. The influence of convective mass
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
over a temperature range from 575 C to 975 C. The influence of convective mass
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
over a temperature range from 575 C to 975 C. The influence of convective mass
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
2O3 with chlorine to produce YOCl was studied by thermogravimetry
over a temperature range from 575 C to 975 C. The influence of convective mass
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
C to 975 C. The influence of convective mass
transfer into the boundary layer surrounding the sample, gaseous diffusion into the sample pores,
partial pressure of chlorine, and temperature on the reaction rate were analyzed in order to
determine the rate-controlling step. The thermogravimetric and scanning electron microscopy
(SEM) results showed that the process follows a model of nucleation and growth, and the process
is chemically controlled for temperatures lower than 800 C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
C, with an activation energy (Ea) of
187 ± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2± 3 kJ/mol. In the 850 C to 975 C range the reaction rate was affected by diffusion of Cl2
through the gas film surrounding the sample, with apparent Ea of 105 ± 11 kJ/mol.
A global rate equation that includes these parameters has been developed R ¼ da=dt ¼
A global rate equation that includes these parameters has been developed R ¼ da=dt ¼
A global rate equation that includes these parameters has been developed R ¼ da=dt ¼
A global rate equation that includes these parameters has been developed R ¼ da=dt ¼
Ea of 105 ± 11 kJ/mol.
A global rate equation that includes these parameters has been developed R ¼ da=dt ¼¼ da=dt ¼
105 kPa1 exp 187 kJmol15 kPa1 exp 187 kJmol1
RT pCl21:51 ð1 aÞ½lnð1 aÞ0:34T pCl21:51 ð1 aÞ½lnð1 aÞ0:34