DE1270032B - Process for the production of olefins - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY GERMAN WT ^ S PATENT OFFICE

EDITORIAL

Int. CL:

German class:

Number:
File number:
Registration date:
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C07c

BOIj

12 ο -19/01

12 g -11/64 12 g-11/78

P 12 70 032.2-42 May 14, 1963 June 12, 1968

The production of higher olefins by reacting tertiary alkyl halides in the presence of Zinc chloride is known as a catalyst at low temperature. The implementation should be done by a shake the reaction mixture for several days. It is also known, ethylene with tert-butyl chloride in the presence of anhydrous aluminum chloride at -10 ° C or with ferric chloride 24 ° C to implement l-chloro-3,3-dimethylbutane.

In contrast, the invention is used in the production process described below of olefins a class of catalysts, the use of which leads to a technical improvement in leads in several ways. The catalysts of the invention are not highly corrosive like the catalysts proposed in the prior art, cooling of the reaction mixture - such as it is necessary, for example, when working with aluminum chloride - is not necessary here.

The invention accordingly provides a process for the production of olefins in which from a halogen-substituted paraffin and an olefinically unsaturated hydrocarbon in the presence of a halogenated catalyst is a higher alkyl chloride built up and this is then catalytically dehydrohalogenated, which is characterized by is that the same or different catalysts are used in both stages, each through Treatment of a halogenatable metal oxide of III. to V. or VIII. group of the periodic table or a mixture of such oxides with a compound having the group Process for the production of olefins

Applicant:

The British Petroleum Company Limited, London

Representative:

Dr.-Ing. A. v. Kreisler, Dr.-Ing. K. Schönwald, Dr.-Ing. Th. Meyer and Dipl.-Chem. Dr. rer. nat. J. F. Fues, Patent Attorneys, 5000 Cologne 1, Deichmannhaus

Named inventor: Anthony George Goble, Sunbury-on-Thames, Middlesex (Great Britain)

Claimed Priority: Great Britain May 15, 1962 (18,627)

of the invention are CHCl ₃ , CCl ₄ , CH ₂ Cl-CHCl ₂ and tertiary butyl chloride.

According to the invention, those can be obtained by the following Typical reactions shown in equations are performed;

CH ₃

CH ₃ -C -CH-C ₂ H ₄

, Shark

CH ₃

CH ₃

contains, in the shark and shark 'same or different Are halogen atoms,

The method according to the invention is preferably carried out at temperatures in the range from -3Q to
350 ° C carried out. It can be used at reduced pressure,
Normal pressure or positive pressure can be used. -

The starting material is passed over the catalyst in the vapor phase or liquid phase. Preferably an inert carrier gas such as nitrogen is used.

As olefinically unsaturated compounds to be used, as halogenable inorganic oxides fertilize come for example ethylene, propylene, 50 preferably heat-resistant metal oxides from the n- or isobutenes and higher olefins in question. Groups III to V or from group VIII des Typical halogen-substituted paraffins used for the purposes of the Periodic Table, for example oxides

809 559/532

CH ₃ CH ₃

CH ₃ -C -CH = CH ₈

CH ₃

3 4

of aluminum, boron, silicon, titanium, zirconium or the retained alkali or alkaline earth metal ferric oxide, alumina is preferred. amount can be in proportion to the amount of anorga-also Mixtures of two or more inorganic frilly oxides can be small and, for example, in BeOxyden can be used if necessary. rich from 0.01 to 10% of the weight of the inorganic

If aluminum oxide is used, the 5 niche oxide should be used. The minimum amount that

position of the catalyst contains the aluminum oxide is required for any given application,

preferably some hydrogen. This is a feature to make the catalyst selective, can experi-

of activated aluminum oxides, which are indeed determined over the mind. That about the minimum quantity

consist mainly of aluminum oxide, but a metal that is also present is not disadvantageous. It

low, usually less than 1 weight percent, io has been found to involve significant amounts of halogen

Contain amount of hydrogen. One is generally the one that can be absorbed by oxides

View that this hydrogen in the form of upper alkali metal in amounts of, for example, 4 Ge

surface hydroxyl groups are present and that by weight percent and more.

Halogen compound halogen in the alumina The catalyst is preferably formed by

in the places of at least part of the origin, the treated inorganic oxide at increased

borrowed superficial hydroxyl groups, forming temperature with the vapors of a compound

is introduced by active catalyst sites. the general formula

All aluminum oxide forms that are suitable as

Support for reforming catalysts in question 1

come. However, one of 20 'is particularly preferred

form derived from an alumina hydrate precursor, X - C - Cl
in which the trihydrate predominates. Particularly suitable

is a form of alumina that has a larger Y
Contains a portion of aluminum oxide trihydrate. The aluminum oxide can be in a simple manner by 25 in which X and Y are the same or different and H, hydrolysis of an aluminum alcoholate, z. B. Alu- Cl, Br or SCl or in which X and Y are ammonium isopropoxide, in an inert hydrocarbon sammen O or S, is brought together, substance as a solvent, z. B. Benzene, produce. If necessary, however, other compounds containing the activity can also be used. The preference of the catalyst, the higher, the greater the number of compounds used in which the aluminum oxide is absorbed by halogen, group > CCl ₂ not directly to a carbon atom and since the maximum amount of halogen that is attached to the atom is bound.

can be related to the size of the surface. The subsequent chlorination is essentially

it is advantageous if the aluminum oxide is borrowed in the same way as it

a large surface of, for example, more than 35 in the German Auslegeschrift 1194 378 of the invention

250m ² / g, preferably more than 300m ² / g, which is described. Suitable compounds with

having. of the required structural formula

The halogenable inorganic carbon tetrachloride (CCl ₄ ) is expedient.

Oxide before halogenation with an alkali or chloroform (CHCl 1

Alkaline earth metal compound under such conditions 40 methylene chloride (CH Cl)

treated that alkalt or alkaline earth metal by dichlorodifluoromethane'iCCl ^

the oxide is retained in the formation of trichlorobromomethane (CCl ₃ Br)

of the catalyst used alkali or alkaline earth phoses (COCl ")

metal compounds are preferably compounds, thiophosgene (CSCl ")

those under the conditions under which they were 45

inorganic oxide are brought together, or of the compounds listed are the

preferred among the later but prior to halogenation of the first three. In the case of connections,

Catalyst conditions applied metal- those except chlorine, carbon and hydrogen still

able to deliver cations. may contain other elements

The exact way in which the additive 50 adds the other elements in addition to chlorine to the of an alkali or alkaline earth metal, a change is attached to the catalyst. For example, one has Beder Activity of the catalyst is effected, no action with dichlorodifluoromethane results in that known for certain, however, it is believed both chlorine and fluorine due to the catalyst that the metal cation will somehow be absorbed with the inorga-. The presence of these others niche oxide connects. Preferably, therefore, 55 elements will not be affected by the chlorine the oxide is subject to activity after the addition of a treatment, but can produce other properties, through which the alkali or alkaline earth metal shafts are introduced, so that through corresponding Compound is decomposed, for example a Calci- care must be ensured that the Seleknierung, and preferably compounds activity of the catalyst is not impaired, used, which can be decomposed without 60 Small amounts of halogen (including chlorine) can change Elements remain on the oxide. nen in the catalyst even before the chlorination Particularly suitable compounds are the salts that are present without being caused by the chlorination from organic acids, especially from carbon-conferred activity. For example acids, e.g. B. the formates, acetates and oxalates. it may be the inorganic oxide that the The alkali or alkaline earth metal compounds can be subjected to treatment according to the invention, Impregnate the inorganic oxide in a simple manner by using a platinum-aluminum oxide catalyst with solutions of the compounds to yours, which contains up to 1 weight percent halogen, are given. as he normally used to reform im

Gasoline range boiling hydrocarbons is used.

Suitable fluorinating compounds are, for example, methylene fluoride, fluoroform and carbon tetrafluoride. The latter is preferred. Tetrafluorocarbon is an extremely stable compound and does not appear at first glance to be suitable for the production of fluorine-containing catalysts. Nevertheless it was found to be useful and has advantages over other fluorinating compounds.

Preference is given to the temperature, contact time and amount of the halogen-containing compound in the preparation of the catalyst chosen so that the halogen uptake is at least 1 percent by weight. There the halogenation is essentially a surface phenomenon, the amount of halogen is without Formation of free metal halide can be deposited with the surface area of the catalyst in connection. The larger the surface, the greater the amount of halogen that can be used without the formation of free halide can be attached. Usually this amount of halogen is at least half as large like the amount that could have been added without the formation of free halide if the catalyst had not been treated with an alkali or alkaline earth metal.

The non-reducing conditions used for halogenation can be either inert or oxidizing conditions. The latter are preferred. A simple method of Treatment of the metal oxide consists in taking the halogen compound as a gaseous stream alone or preferably to pass over the metal oxide in a non-reducing carrier gas. Suitable Carrier gases are, for example, nitrogen, air and oxygen.

Non-reducing conditions are preferred because, with some catalysts, reducing conditions convert the halogen compound to hydrogen halide, thereby yielding inactive catalysts. The halogenation temperature may be 149 to 593 ⁰ C. When using aluminum oxide, the tendency towards the formation of free aluminum halide increases with increasing temperature. Care must therefore be taken when working in the specified range at the higher temperatures. Since the temperatures used are normally above the volatilization temperature of aluminum halide, the formation of free aluminum halide can easily be detected by its appearance in the gaseous reaction products. When treating a catalyst composed of a platinum group metal and alumina, care should be taken to prevent the formation of volatile platinum complexes. The tendency to form such complexes also increases with increasing temperature. When treating catalysts which consist of a platinum group metal and aluminum oxide, the temperature is preferably between 149 and 371 ^{° C., with temperatures between 232 and 316 °} C. for the combination of platinum on aluminum oxide and temperatures between in particular between 260 and 343 ° C can be used. The halogenation reaction is exothermic and the temperatures mentioned are the initial temperatures used.

The rate at which the halogen compound is supplied is preferably as low as possible to ensure uniform halogenation and rapid temperature rise than Avoid consequence of the exothermic reaction. The amount supplied is preferably not greater than this 1.3 percent by weight of halogen compound per minute, based on the catalyst. When using a Carrier gas is the flow velocity

ίο preferably at least 200 V / V catalyst / hour.

A range of 200 to 100OV / V / hour is suitable here. It is useful at normal pressure worked.

In the presence of water, the active catalyst is subject to hydrolysis. It must therefore be stored under anhydrous conditions. The substances used in the manufacture of the catalyst must also be anhydrous.
Suitable conditions for the preparation of the catalyst are given in German Auslegeschrift 1194378 and in British Patent 932 342 of the inventor.

example

A chlorinated alumina catalyst was prepared using a stream of dry air that 0.49 percent by volume of carbon tetrachloride vapors, for 4 hours at an amount of 1700 v / v / h. was passed over an alumina catalyst which was kept at 290 to 327 ° C. After Treatment, the catalyst had a chlorine content of 11.8 percent by weight and a pore volume from 0.30.

Ethylene gas was bubbled in an amount of 103 cm ³ / minute through 100 cm ^{3 of} tertiary butyl chloride in which 20 cm ^{3 of} the chlorinated aluminum oxide catalyst were suspended. The liquid was refluxed for 2 hours, cooled and the resulting liquid product decanted. 61.5 g of product were obtained here.

1.2 g of the product was then in a microreactor at 5 to 6 V / V / hr. in a stream of nitrogen at 1200 V / V / hour. and 316 ° C passed over the chlorinated alumina catalyst. This gave 0.53 g of olefinic product which boiled up to 46.degree. Gas chromatographic analysis of this material showed that it contained 20 percent by weight of unreacted tertiary butyl chloride and 15 to 20 percent by weight of C _e olefins. The C _e olefins contained about 40 percent by weight dimethylbutenes. The remainder of the product consisted mainly of C ₄ and C ₅ olefins.

Claims (4)

Patent claims: 1. Process for the production of olefins, in which from a halogen-substituted paraffin and an olefinically unsaturated hydrocarbon in the presence of a halogenated catalyst built up a higher alkyl chloride and then catalytically dehydrohalogenated is, characterized in that the same or different catalysts in both stages are used, each by treating a halogenatable metal oxide the III. to V. or VIII. group of the periodic table or a mixture of such oxides with a connection obtained that the group Ha! contains, in the shark and shark 'same or different Are halogen atoms, 2. The method according to claim 1, characterized in that that the halogenable inorganic metal oxide is a heat-resistant oxide of a metal from groups III to V of the periodic table, in particular aluminum oxide. 3. Process according to Claims 1 and 2, characterized in that the inorganic metal oxide has a surface area greater than 250 m ² / g. 4. Process according to Claims 1 to 3, characterized in that the halogenatable inorganic Metal oxide an alkali metal or alkaline earth metal compound, preferably in one Amount between 0.1 and 10 percent by weight of the inorganic metal oxide. 5. Process according to Claims 1 to 4, characterized in that the catalyst is treated by treatment of the inorganic metal oxide at elevated temperatures and under non-reducing temperatures Conditions with the vapors of a compound of the general formula Cl so as has been obtained in which X and Y are identical or different, mean H, Cl, Br, F or SCl or X and Y together represent O or S. 35 6. Process according to Claims 1 to 5, characterized in that the catalyst is treated by treatment of the inorganic metal oxide with carbon tetrachloride, chloroform or methylene chloride has been received. 7. Process according to Claims 1 to 6, characterized in that in the preparation of the catalyst the temperature, the treatment time and the amount of compound used with the group ,Ha Ha' have been matched to one another in such a way that the inorganic metal oxide is at least 1 percent by weight and not more than 15 percent by weight of halogen, based on the weight of the oxide. 8, process according to claims 1 to 7, characterized in that as olefinically unsaturated Hydrocarbons ethylene, propylene, n- and / or isobutene are used. Process according to Claims 1 to 8, characterized in that the halogen-substituted paraffins used are CHCl 3, CCI ₄ , CH ₈ Cl-CHCl ₂ and / or tert-butyl chloride, 10. Process according to Claims 1 to 9, characterized in that temperatures in the range from -30 to + 35O ⁰ C are used. Considered publications:
Chemisches Zentralblatt, 1956, pp. 14316 to 14317; Houben-Weyl, Methods of Organic Chemistry, 4th Edition, Vol. 5/3, p. 962. 809 559/532 5.6S © Bundesdruckerei Berlin