Chemistry of hydrocarbon compounds – Aromatic compound synthesis – By condensation of entire molecules or entire hydrocarbyl...
Reexamination Certificate
2000-06-22
2002-08-06
Griffin, Walter D. (Department: 1764)
Chemistry of hydrocarbon compounds
Aromatic compound synthesis
By condensation of entire molecules or entire hydrocarbyl...
C585S446000, C585S455000, C585S323000
Reexamination Certificate
active
06429345
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to the field of processes for producing phenylalkanes by alkylating benzene using at least one olefin comprising at least 9 carbon atoms, or comprising at least 14 carbon atoms. More particularly, the hydrocarbon feed used comprises at least one olefin containing 9 to 16 carbon atoms or 10 to 14 carbon atoms or, for example, the hydrocarbon feed used comprises at least one olefin containing 14 to 20 carbon atoms, in the presence of at least one catalyst comprising a zeolite with structure type EUO.
PRIOR ART
The phenylalkanes obtained in accordance with the invention constitute compounds for formulating biodegradable detergents after sulphonation.
Currently, bases for biodegradable detergents mainly use linear alkylbenzenes. This type of compounds is being produced in increasing quantities. In addition to its detergent power, one of the principal desired properties for these compounds after the sulphonation step is biodegradability. To ensure maximum biodegradability, the alkyl group must be linear and long with the distance between the sulphonate group and the terminal carbon on the linear chain being a maximum. The most important benzene alkylation agents are constituted by linear C9-C16 olefins, preferably C10-C14.
The linear alkylbenzenes obtained by alkylating benzene using linear olefin(s) are currently prepared using two major processes. The first process uses hydrofluoric acid as an acidic catalyst during the benzene alkylation step. The second uses a Friedel-Crafts type catalyst, in particular based on AlCl
3
. Those two processes lead to the formation of 2-, 3-, 4-, 5- and 6-phenylalkanes. The principal drawback of those processes is connected to environmental constraints. The first process based on the use of hydrofluoric acid causes severe safety problems and discharge re-treatment problems. The second process causes the conventional problem linked with Friedel-Crafts type catalysts, namely with the discharges; for that type of process, the effluents have to be neutralised by a basic solution at the reactor outlet. These various drawbacks are supplemented by difficulties linked with separation of the catalyst from the reaction products in both processes.
These various constraints explain the interest in developing a process for alkylating benzene using linear olefins in the presence of a solid catalyst.
The prior art is primarily based on the use of catalysts with geometrical selectivity properties and leading to improved selectivity for 2- and 3-phenylalkane. Such catalysts with geometrical selectivity properties are constituted by zeolites. Thus United States patent U.S. Pat. No. 4,301,317 claims a series of zeolites, namely: cancrinite, gmelinite, mordenite, offretite and ZSM-12. In particular, such zeolites are characterized in that their pore opening is in the range from about 6 to about 7 Å in diameter (1 Å=10
−10
m).
A patent application filed by the Applicant and published with number FR-2 697 246 demonstrates that catalysts based on dealuminated Y zeolite can be used. Y zeolites with a pore opening of close to 7.4 Å do not fall within the scope of U.S. Pat. No. 4,301,317. Regarding the use of Y zeolites, European patent EP-A-0 160 144 claims the use of low crystallinity Y zeolites (crystallinity in the range 30% to 80%), and U.S. Pat. No. 5,036,033 claims the use of Y zeolites rich in ammonium cations.
SUMMARY OF THE INVENTION
The invention provides a process for producing at least one compound selected from 2-, 3-, 4-, 5- and 6-phenylalkanes by alkylating benzene using at least one olefin containing at least 9 carbon atoms per molecule, in the presence of a solid zeolitic catalyst, characterized in that the catalyst comprises a matrix and a zeolite with structure type EUO, said zeolite comprising silicon and at least one element T selected from the group formed by aluminium, iron, gallium and boron, with an overall Si/T atomic ratio of more than 5, characterized in that said alkylation is carried out at a pressure in the range 0.1 to 10 MPa, a temperature in the range 30° C. to 400° C., and with an hourly space velocity of 0.50 to 200 h
−1
, and a benzene/olefin(s) mole ratio in the range 1:1 to 50:1. More particularly, the invention concerns alkylating benzene using a linear olefin for the production of linear phenylalkanes.
IMPORTANCE OF THE INVENTION
We have discovered that the use of catalysts comprising at least one zeolite with structure type EUO, at least partially in its acid form and at least one matrix, said zeolite comprising silicon and at least one element T selected from the group formed by aluminium, iron, gallium and boron (preferably aluminium and boron), with an Si/T atomic ratio of more than 5, on alkylating benzene with olefin(s) as defined above, exhibits catalytic performances which are better than those of the catalysts described in the prior art. These novel catalysts are simultaneously highly active, highly selective and highly resistant to deactivation.
DESCRIPTION OF THE INVENTION
In the present invention, in addition to at least one olefin as defined above, the hydrocarbon feed used to alkylate the benzene ring can contain one or more paraffins, one or more other aromatic compound(s), one or more polyolefinic compound(s) (for example diolefinic), one or more mono- and/or polyunsaturated non linear olefin(s). These cuts can also contain one or more alpha-olefins in highly variable quantities from a trace to very large quantities which may even be in the majority compared with said feed. The olefins can be linear or branched olefins.
The process of the present invention can produce, preferably simultaneously, at least one compound selected from 2-, 3-, 4-, 5- and 6-phenylalkanes. In the case where the feed comprises linear olefins,, the process of the invention can produce mainly linear phenylalkanes. In the case where the feed comprises branched olefins, the process of the invention can produce mainly branched phenylalkanes.
The catalyst used in the present invention comprises at least one zeolite with structure type EUO, for example EU-1 zeolite, at least partially in its acid form and at least one matrix (binder), said zeolite comprising silicon and at least one element T selected from the group formed by aluminium, iron, gallium and boron, preferably aluminium and boron, with an Si/T atomic ratio of more than 5. Further, this catalyst formed, for example into beads or extrudates, has good mechanical strength.
EU-1 zeolite with structure type EUO, which has already been described in the prior art, has a unidimensional microporous network with a pore diameter of 4.1×5.7 Å (1 Å=1 Angström=1×10
−10
m) (“Atlas of Zeolite Structure Types”, W. M. Meier and D. H. Olson, 4th edition, 1996). Further, N. A. Briscoe et al. have disclosed in an article in the review Zeolites (1988, 8, 74) that these unidimensional channels have lateral pockets with a depth of 8.1 Å and a diameter of 6.8×5.8 Å. The mode of synthesis of EU-1 zeolite and its physico-chemical characteristics have been described in European patent EP-B1-0 042 226. U.S. Pat. No. 4,640,829 concerns ZSM-50-zeolite, which has the same EUO structure type as EU-1 zeolite according to the “Atlas of Zeolite Structure Types”, W. M. Meier and D. H. Olson,
4
th edition, 1996. Said patent has a different mode of synthesis of the ZSM-50 to that described in EP-B1-0 042 226 regarding EU-1 zeolite. EP-A1-0 051 318 deals with TPZ-3 zeolite which has the same EUO structure type as EU-1 zeolite according to “Atlas of Zeolite Structure Types”, W. M. Meier and D. H. Olson, 4th edition, 1996, and describes its use as a catalyst containing the zeolite as it is or formed. In said document, an example of forming TPZ-3 zeolite is the preparation of pellets, obtained by pelletising a mechanical mixture of powdered zeolite and binder. The pellets comprise TPZ-3 zeolite, a binder and optionally at least one element selected from the group formed by ir
Alario Fabio
Joly Jean-François
Magne-Drisch Julia
Merlen Elisabeth
Griffin Walter D.
Institut Francais du Pe'trole
Miilen, White, Zelano & Branigan, P.C.
LandOfFree
Process for production phenylalkanes using a catalyst based... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for production phenylalkanes using a catalyst based..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for production phenylalkanes using a catalyst based... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2934377