INVESTIGADORES
QUERINI carlos Alberto
artículos
Título:
Skeletal isomerization of 1-butene on ferrierite: Deactivation and regeneration conditions
Autor/es:
FINELLI, ZUNILDA; QUERINI, CARLOS A; FIGOLI, NORA S; COMELLI, RAÚL A
Revista:
APPLIED CATALYSIS A-GENERAL
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 1999 vol. 187 p. 115 - 125
ISSN:
0926-860X
Resumen:
The skeletal isomerization of 1-butene on ferrierite at 350C and 400C, atmospheric pressure and 0.14 atm 1-butene partial
pressure is studied. The rapid decrease in activity with an increase in the isobutene selectivity is related to coke deposition. The
carbon content is similar for both reaction temperatures. Temperature-programmed oxidation profiles of the used catalysts
show two peaks for coke combustion, one each at low and high temperatures. The low-temperature peak is higher when
reaction takes place at 350C while the one at high temperatures is larger for reaction at 400C. The carbonaceous deposits
corresponding to the low-temperature combustion peak can be eliminated after stripping with a helium stream, suggesting
that these deposits are rich in hydrogen. Diffuse-reflectance infrared spectroscopy measurements indicate that coke presents
olefinic and aromatic character for all samples, being more olefinic after reaction at 350C and more aromatic after reaction
at 400C. The presence of water during the treatment before the reaction changes the proportion of olefinic and aromatic coke
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
at 400C. The presence of water during the treatment before the reaction changes the proportion of olefinic and aromatic coke
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
at 400C. The presence of water during the treatment before the reaction changes the proportion of olefinic and aromatic coke
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
corresponding to the low-temperature combustion peak can be eliminated after stripping with a helium stream, suggesting
that these deposits are rich in hydrogen. Diffuse-reflectance infrared spectroscopy measurements indicate that coke presents
olefinic and aromatic character for all samples, being more olefinic after reaction at 350C and more aromatic after reaction
at 400C. The presence of water during the treatment before the reaction changes the proportion of olefinic and aromatic coke
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
at 400C. The presence of water during the treatment before the reaction changes the proportion of olefinic and aromatic coke
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
at 400C. The presence of water during the treatment before the reaction changes the proportion of olefinic and aromatic coke
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
corresponding to the low-temperature combustion peak can be eliminated after stripping with a helium stream, suggesting
that these deposits are rich in hydrogen. Diffuse-reflectance infrared spectroscopy measurements indicate that coke presents
olefinic and aromatic character for all samples, being more olefinic after reaction at 350C and more aromatic after reaction
at 400C. The presence of water during the treatment before the reaction changes the proportion of olefinic and aromatic coke
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
at 400C. The presence of water during the treatment before the reaction changes the proportion of olefinic and aromatic coke
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n-butene isomerization consists of an oxidative treatment at high temperatures, but without the complete coke
removal
removal
removal
at 400C. The presence of water during the treatment before the reaction changes the proportion of olefinic and aromatic coke
formed. Regeneration under a nitrogen plus air stream at 660C for 15 h allows almost complete elimination of the coke and
full restoration of the catalytic activity to that of the fresh sample. However, the presence of a residual carbonaceous deposit
(i.e. 0.9 wt.%) when starting the reaction, improves catalytic activity, isobutene yield and catalyst stability after some minutes
on stream, as compared to the fresh sample. Therefore, we propose that the optimum regeneration procedure for ferrierite
catalyst for n