CA1137062A - Process for the "in-situ" fluorination of a catalyst - Google Patents
Process for the "in-situ" fluorination of a catalystInfo
- Publication number
- CA1137062A CA1137062A CA000326392A CA326392A CA1137062A CA 1137062 A CA1137062 A CA 1137062A CA 000326392 A CA000326392 A CA 000326392A CA 326392 A CA326392 A CA 326392A CA 1137062 A CA1137062 A CA 1137062A
- Authority
- CA
- Canada
- Prior art keywords
- catalyst
- gas
- fluorine
- fluorine compound
- organic fluorine
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/22—Halogenating
- B01J37/26—Fluorinating
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Catalysts (AREA)
- Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
Abstract
A B S T R A C T
Rapid in situ fluoridation at elevated temperature and pressure of hydrotreating catalysts with gaseous organic fluorine compounds, e.g., difluoroethane is disclosed. The fluorine com-pound is injected all at once in a gas preferably hydrogen, which is recycled through the hydrotreating plant. The gas is recycled until analyses on concentrations of a decomposition product of the injected fluorine compound, e.g., ethane, in the recycling gas indicates that the desired amount of fluorine has been incor-porated on the catalyst. This process provides an even distribu-tion of the fluorine on the catalyst, and permits the use of rela-tively low temperatures.
Rapid in situ fluoridation at elevated temperature and pressure of hydrotreating catalysts with gaseous organic fluorine compounds, e.g., difluoroethane is disclosed. The fluorine com-pound is injected all at once in a gas preferably hydrogen, which is recycled through the hydrotreating plant. The gas is recycled until analyses on concentrations of a decomposition product of the injected fluorine compound, e.g., ethane, in the recycling gas indicates that the desired amount of fluorine has been incor-porated on the catalyst. This process provides an even distribu-tion of the fluorine on the catalyst, and permits the use of rela-tively low temperatures.
Description
~ 7~
;
A PROCESS FOR ~E "IN-SIT~" ~L~ORIN~ION 0~ A CA~A~YS~
~he present invention relates to a process~for the~"in-situ"
fluorination of a catalyst containing alumina and one or more metals of groups VI~5; ~II3 and VIII of the periodic table of chemicals elements ~ , in which process a quantity of gaseous 5 organic fluorine compound is contacted with the catalyst at ~ ~
elevated temperature and pressure, the reactor ef~luent gas ~ ;
being recycled. ~ ~
~he present invention further relates to a catalyst which ~ ;
has been flucrinated b~ the ab;ove process and to process for ~ -the catalytic conversion of hydrocarbons by means of said oatalyst.
~he fluorinated catalysts are important for various :: , processes, such as isomerization, reforming, alkylation, hydration~ disproportionation, polymerization and hydrogenative and non-hydrogenative crac~ing.
According to processes known in the art, the catalysts ~ were activated by~a treatment with fluorine by means of an ; aqueous hydrofluoric solution or gaseous boron fluorides.
:
A fluorination agent of these t~pes cause corrosion of the equipment.
.
)~andbook of Chemistry~and Physics - 44th Edition 1962-1363, Chemical ~ubber Publishing Co., ~ages 448-449 ;
- : . ' 7~
It has been found that catalytically active, fluorinated catalysts can also be prepared by means of an organic fluorine compound. The advantage of suoh a compound is that it is less corrosive.
3xamples of such organic fluorine compounds are difluo~o-ethane, orthofluorotoluene, hexafluoro-ethane, hexafluoro-aoetone, octafluoropropane, 1 fluoro-2-meth~lpropane, deca-fluorodiethylether, hexafluorobenzene and hexadeoafluoropro-pyloxane. ~he organic fluorine compound can be rendered chemically reactive by oatalytio h~drogen~tion of the supported elemants of groups VI~, VlI3 and VIII of the periodic table of chsmical elements, so that for example alumina oontaining these elements can be activated and provided with fluorine.
~he catalyst may be fluorinated in-situ, i.e. in the reaotor itself for the conversion of hydrooarbons, fcr example by introducing the fluorins oompound by means of a oarrier gas into the reactor whers the fluorine compound contacts the catalyst. ~hs addition of the fluorine cbmpound i9~ usually carried out in a non-continuous manner~ ~he du~ation of the injection of the fluorins compound which is oontacted with the catalyst depends on t~he fluorination tsmperature and the quantity to be ~njeoted. ~his injection period may last up to i~
70 hours but~may be reduoea to less than 24 hours provided a fluorination temperature above 250C is used.
In this case ths fluorination period is equal to the injection period.
~he application of such a teohnique does not allow a homo~eneous distribution of fluorine over the catalyst bed to be obtained It has now been found that, if the necessary quantity of fluorine compound is added at once to tne reoyole gas of the reactor in which the catalyst to be fluorinated is present, the fluorination temperature oan be reduced to a level below - 200C In this case the duration of the requirsd fluorination can bs reducsd to 10 hours. A treatment with fluorine according to this finding rssults in a good distribution - of fluorine on the catalyst. ~his process further :
, . . . .
:,, ~ : :
~: :: :-::
7~
offers the advantage that the fluorination process can be readily followed by analysing the recycle gas and determining the concent~ations of the decomposition products of the added organic fluorine compound.
~he invention, therefore~ relates to a process for the in situ fluorination of a catalyst containing alumina and at least one metal of Groups VI~ and VIII of the periodic table of chemical elements, in which process a gaseous organic fluorine compound is contacted in a reactor with the catalyst, at elevated temperature and pressure, the reactor effluent gas being recycled. It is characterized in that the duration of the injeotion of the organic fluorine compound into the gas is reduced to one imp~lsion.
Preferably, the duration of the injection is between 0.1 and 10 seconds. ~he organic fluorine compound is preferably injected into the recycle gas at a pressure of 0.5-50 bar, while the space velocity of the gas is preferably 400-600 NL/Xg of catalyst/hour.
To prevent tha equipment from being attacked by corrosion, the recycle gas is preferably washed with water. In this manner the recirculation gas system is freed from any traces of highly corrosive hydrofluoric acid formed during the decomposition of the~organic fluorine compound and not absorbed by the ca~talyst.
In order to deposit the required quantity of fluorine on the catalyst? a quantity of organic fluorine compound is preferably injected corresponding to 2-6% by weight of fluorine, based on the total weight of the catalyst to be fluorinated.
~he organic fluorine compound used is preferably difluoroethane, since the fluorination process with this compound is easy to follow. In fact~ tha recycle gas is then measured for the quantity of ethane which separates off as a decomposition product of difluoroethane during the fluorination ~` and which i~ present in the recycle gas.
3~ ln addition to a process for the fluorination of a catalyst the invention relates to a catalyst ;
fluorinated by the abova~entioned process and to aprocess for the catalytic conver~ion of hydrocarbons at elevated temperature and pressure in the presence of hydrogen, in which process use is made of the above-mentioned catalyst and of the `
hydrocarbons obtained by mean~ of said process.
The invention will be illustrated by means of the following e~amples.
Exam~e I
In a reactor for the hydrocracking o~` hydrocarbons 1 kg of catalyst containing alumina as well as 5.1% by weight of nickel and 23.4% by wsight of tungstenj based on the total weight of the catalyst~ was first sulphided with heavy Euwait gas oil at a maximum temperature of 375C and at a pressure of 50 bar. After sulphidation the temperature was - 15 reduced to 150C and the pre~sure to 35 bar, while the space velocity of the recycle gas was brough-t to 500 Nl/kg of catalyst/hour. 0.0~7 kg of difluoroethane, corresponding to 5~ by weight of fluorine based on the total weight of the catalyst, was injected in 1 second~into the recycls gas at a~
pressure of 35 bar, and after the recycle gas had~been homogenizsd the temperature was gradually brought to 190C.
- During fluorination the recycle gas was analysed to - determine its ethane content, to enable the fluorinationprocess to be followed. After 9 hours the process was stopped. ;~
According to the analysis of the quantity of ethane in the recycle gas, there was at that moment 3S6 by weight of fluorine on the catalyst.
Analysis of the fluorine on the catal~Jst showed that the - fluorine was diviaad homogeneously on the catalyst; the weight - 3~ percentage of fluorine then corresponded to the above-mentioned percentage according to the analysis of the rec~cle gas.
~ample II
1 kg of catalyst containing the same quantity of nicXel, tungstsn and alumin2 as that of ~xample I was fluorinated after sulphidation wlth heavy Kuwait gas oil ~nder the ~a~e ,, :
- - , : ~ ,:
~ ' ' '' , '~ . ~
, 11 ~ 7 OOz conditions of temperature and pressure as in Example I, by injection of 0.057 kg of difluoroethane, corresponding to 3.3%
by weight of fluorine based on the total weight of catalyst, injected in 1 second into the recycle gas from the reactor at a pressure of 35 bar.
In the latter case the space velocity of the recycle gas was also 500 ~TL/kg of catalyst/hour. After 20 hours the fluorination was stopped after analysis of the ethane in the reoycle gas had indicated that the quantity cf fluorine on the catalyst was 3~ by weight. ~his fact was confirmed by subsequent analysis of the fluorine present on the catalyst.
In view of the rasults o the tests described in the ~amples, it is obvious that the process according to the invention not only provides a rapid fluorination method, but ~- t5 that it also offers the possibility to follow the exact degree ~` of fluorination by mea~s of analysis of the recycle gas, thereby enabling the process to be followed closely, .
, ,. . .
.:
.
.
;
A PROCESS FOR ~E "IN-SIT~" ~L~ORIN~ION 0~ A CA~A~YS~
~he present invention relates to a process~for the~"in-situ"
fluorination of a catalyst containing alumina and one or more metals of groups VI~5; ~II3 and VIII of the periodic table of chemicals elements ~ , in which process a quantity of gaseous 5 organic fluorine compound is contacted with the catalyst at ~ ~
elevated temperature and pressure, the reactor ef~luent gas ~ ;
being recycled. ~ ~
~he present invention further relates to a catalyst which ~ ;
has been flucrinated b~ the ab;ove process and to process for ~ -the catalytic conversion of hydrocarbons by means of said oatalyst.
~he fluorinated catalysts are important for various :: , processes, such as isomerization, reforming, alkylation, hydration~ disproportionation, polymerization and hydrogenative and non-hydrogenative crac~ing.
According to processes known in the art, the catalysts ~ were activated by~a treatment with fluorine by means of an ; aqueous hydrofluoric solution or gaseous boron fluorides.
:
A fluorination agent of these t~pes cause corrosion of the equipment.
.
)~andbook of Chemistry~and Physics - 44th Edition 1962-1363, Chemical ~ubber Publishing Co., ~ages 448-449 ;
- : . ' 7~
It has been found that catalytically active, fluorinated catalysts can also be prepared by means of an organic fluorine compound. The advantage of suoh a compound is that it is less corrosive.
3xamples of such organic fluorine compounds are difluo~o-ethane, orthofluorotoluene, hexafluoro-ethane, hexafluoro-aoetone, octafluoropropane, 1 fluoro-2-meth~lpropane, deca-fluorodiethylether, hexafluorobenzene and hexadeoafluoropro-pyloxane. ~he organic fluorine compound can be rendered chemically reactive by oatalytio h~drogen~tion of the supported elemants of groups VI~, VlI3 and VIII of the periodic table of chsmical elements, so that for example alumina oontaining these elements can be activated and provided with fluorine.
~he catalyst may be fluorinated in-situ, i.e. in the reaotor itself for the conversion of hydrooarbons, fcr example by introducing the fluorins oompound by means of a oarrier gas into the reactor whers the fluorine compound contacts the catalyst. ~hs addition of the fluorine cbmpound i9~ usually carried out in a non-continuous manner~ ~he du~ation of the injection of the fluorins compound which is oontacted with the catalyst depends on t~he fluorination tsmperature and the quantity to be ~njeoted. ~his injection period may last up to i~
70 hours but~may be reduoea to less than 24 hours provided a fluorination temperature above 250C is used.
In this case ths fluorination period is equal to the injection period.
~he application of such a teohnique does not allow a homo~eneous distribution of fluorine over the catalyst bed to be obtained It has now been found that, if the necessary quantity of fluorine compound is added at once to tne reoyole gas of the reactor in which the catalyst to be fluorinated is present, the fluorination temperature oan be reduced to a level below - 200C In this case the duration of the requirsd fluorination can bs reducsd to 10 hours. A treatment with fluorine according to this finding rssults in a good distribution - of fluorine on the catalyst. ~his process further :
, . . . .
:,, ~ : :
~: :: :-::
7~
offers the advantage that the fluorination process can be readily followed by analysing the recycle gas and determining the concent~ations of the decomposition products of the added organic fluorine compound.
~he invention, therefore~ relates to a process for the in situ fluorination of a catalyst containing alumina and at least one metal of Groups VI~ and VIII of the periodic table of chemical elements, in which process a gaseous organic fluorine compound is contacted in a reactor with the catalyst, at elevated temperature and pressure, the reactor effluent gas being recycled. It is characterized in that the duration of the injeotion of the organic fluorine compound into the gas is reduced to one imp~lsion.
Preferably, the duration of the injection is between 0.1 and 10 seconds. ~he organic fluorine compound is preferably injected into the recycle gas at a pressure of 0.5-50 bar, while the space velocity of the gas is preferably 400-600 NL/Xg of catalyst/hour.
To prevent tha equipment from being attacked by corrosion, the recycle gas is preferably washed with water. In this manner the recirculation gas system is freed from any traces of highly corrosive hydrofluoric acid formed during the decomposition of the~organic fluorine compound and not absorbed by the ca~talyst.
In order to deposit the required quantity of fluorine on the catalyst? a quantity of organic fluorine compound is preferably injected corresponding to 2-6% by weight of fluorine, based on the total weight of the catalyst to be fluorinated.
~he organic fluorine compound used is preferably difluoroethane, since the fluorination process with this compound is easy to follow. In fact~ tha recycle gas is then measured for the quantity of ethane which separates off as a decomposition product of difluoroethane during the fluorination ~` and which i~ present in the recycle gas.
3~ ln addition to a process for the fluorination of a catalyst the invention relates to a catalyst ;
fluorinated by the abova~entioned process and to aprocess for the catalytic conver~ion of hydrocarbons at elevated temperature and pressure in the presence of hydrogen, in which process use is made of the above-mentioned catalyst and of the `
hydrocarbons obtained by mean~ of said process.
The invention will be illustrated by means of the following e~amples.
Exam~e I
In a reactor for the hydrocracking o~` hydrocarbons 1 kg of catalyst containing alumina as well as 5.1% by weight of nickel and 23.4% by wsight of tungstenj based on the total weight of the catalyst~ was first sulphided with heavy Euwait gas oil at a maximum temperature of 375C and at a pressure of 50 bar. After sulphidation the temperature was - 15 reduced to 150C and the pre~sure to 35 bar, while the space velocity of the recycle gas was brough-t to 500 Nl/kg of catalyst/hour. 0.0~7 kg of difluoroethane, corresponding to 5~ by weight of fluorine based on the total weight of the catalyst, was injected in 1 second~into the recycls gas at a~
pressure of 35 bar, and after the recycle gas had~been homogenizsd the temperature was gradually brought to 190C.
- During fluorination the recycle gas was analysed to - determine its ethane content, to enable the fluorinationprocess to be followed. After 9 hours the process was stopped. ;~
According to the analysis of the quantity of ethane in the recycle gas, there was at that moment 3S6 by weight of fluorine on the catalyst.
Analysis of the fluorine on the catal~Jst showed that the - fluorine was diviaad homogeneously on the catalyst; the weight - 3~ percentage of fluorine then corresponded to the above-mentioned percentage according to the analysis of the rec~cle gas.
~ample II
1 kg of catalyst containing the same quantity of nicXel, tungstsn and alumin2 as that of ~xample I was fluorinated after sulphidation wlth heavy Kuwait gas oil ~nder the ~a~e ,, :
- - , : ~ ,:
~ ' ' '' , '~ . ~
, 11 ~ 7 OOz conditions of temperature and pressure as in Example I, by injection of 0.057 kg of difluoroethane, corresponding to 3.3%
by weight of fluorine based on the total weight of catalyst, injected in 1 second into the recycle gas from the reactor at a pressure of 35 bar.
In the latter case the space velocity of the recycle gas was also 500 ~TL/kg of catalyst/hour. After 20 hours the fluorination was stopped after analysis of the ethane in the reoycle gas had indicated that the quantity cf fluorine on the catalyst was 3~ by weight. ~his fact was confirmed by subsequent analysis of the fluorine present on the catalyst.
In view of the rasults o the tests described in the ~amples, it is obvious that the process according to the invention not only provides a rapid fluorination method, but ~- t5 that it also offers the possibility to follow the exact degree ~` of fluorination by mea~s of analysis of the recycle gas, thereby enabling the process to be followed closely, .
, ,. . .
.:
.
.
Claims (7)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A process for the in situ fluorination of a catalyst containing alumina and at least one metal of Groups VIB, VIIB and VIII of the periodic table of chemical elements, in which process a gaseous organic fluorine compound is contacted in a reactor with the catalyst at elevated temperature and pressure, the reactor effluent gas being recycled, characterized in that the duration of the injection of the organic fluorine compound into the gas is reduced to one impulsion.
2. A process as claimed in claim 1, characterized in that the duration of the injection is between 0.1 and 10 seconds.
3. A process as claimed in claim 1, characterized in that the organic fluorine compound is injected at a pressure of 0.5-50 bar.
4. A process as claimed in claim 1, 2 ox 3 characterized in that the gas has a space velocity of 400-600 NL/kg of catalyst/hour.
5. A process as claimed in claim 1, 2 or 3 characterized in that the gas is washed with water.
6. A process as claimed in claim 1, 2 or 3 characterized in that a quantity of organic fluorine compound is injected correspond-ing to 2-6% by weight of fluorine, based on the total weight of the catalyst to be fluorinated.
7. A process as claimed in claim 1, 2 or 3 characterized in that difluoroethane is used as organic fluorine compound.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR7820182A FR2430263A1 (en) | 1978-07-06 | 1978-07-06 | PROCESS FOR "IN SITU" FLUORATION OF A CATALYST |
| FR7820182 | 1978-07-06 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1137062A true CA1137062A (en) | 1982-12-07 |
Family
ID=9210413
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000326392A Expired CA1137062A (en) | 1978-07-06 | 1979-04-26 | Process for the "in-situ" fluorination of a catalyst |
Country Status (7)
| Country | Link |
|---|---|
| JP (1) | JPS5511097A (en) |
| CA (1) | CA1137062A (en) |
| DE (1) | DE2927052A1 (en) |
| FR (1) | FR2430263A1 (en) |
| GB (1) | GB2024642B (en) |
| IT (1) | IT7924102A0 (en) |
| NL (1) | NL7905206A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2560068B1 (en) * | 1984-02-28 | 1986-08-01 | Shell Int Research | IN SITU FLUORINATION PROCESS FOR A CATALYST |
| US7485598B2 (en) * | 2006-06-21 | 2009-02-03 | Arkema Inc. | High pressure catalyst activation method and catalyst produced thereby |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3843748A (en) * | 1970-06-25 | 1974-10-22 | Texaco Inc | Isomerization of c10-c14 hydrocarbons with fluorided metal-alumina catalyst |
| GB1459047A (en) * | 1973-03-19 | 1976-12-22 | Shell Int Research | Isomerization catalyst reactivation process |
| CA1067880A (en) * | 1975-04-18 | 1979-12-11 | Shell Canada Limited | Process for the fluoriding of a catalyst |
-
1978
- 1978-07-06 FR FR7820182A patent/FR2430263A1/en active Granted
-
1979
- 1979-04-26 CA CA000326392A patent/CA1137062A/en not_active Expired
- 1979-07-04 DE DE19792927052 patent/DE2927052A1/en not_active Withdrawn
- 1979-07-04 IT IT7924102A patent/IT7924102A0/en unknown
- 1979-07-04 GB GB7923338A patent/GB2024642B/en not_active Expired
- 1979-07-04 NL NL7905206A patent/NL7905206A/en not_active Application Discontinuation
- 1979-07-04 JP JP8405079A patent/JPS5511097A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| NL7905206A (en) | 1980-01-08 |
| FR2430263B1 (en) | 1981-01-02 |
| FR2430263A1 (en) | 1980-02-01 |
| JPS6252623B2 (en) | 1987-11-06 |
| DE2927052A1 (en) | 1980-01-17 |
| IT7924102A0 (en) | 1979-07-04 |
| GB2024642A (en) | 1980-01-16 |
| JPS5511097A (en) | 1980-01-25 |
| GB2024642B (en) | 1982-08-18 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |