DE1468978A1 - Process for the alkylation of aromatic hydrocarbons - Google Patents

Description

Dr. KARL SCHWARZHANS.

Dr. ELISABETH JUNG ΠΠΠΟθΙ © MÜNCHEN 19, den ¹ 3 · J «« * ¹ # *

PATENTANWÄLTE L / V / J «/ ^ ^Wi ROMANPLATZ 10

TEL: 570245

TELEGRAMS: INVENT MÖNCHEN I 4 D O 9 7

p 2307 / J / Kt

3HELL INTEBNATIONALE RESEARCH MAATSCHAPPIJ N.V., Den Hang, Netherlands "Process for alkylating clay aromatic hydrocarbons"

Priority 1 June 17, 1963 / USA Ana 1de no. 288 537

The present invention refers to a new process sun alkylation of aromatic hydrocarbons through a selective · reaction with certain olefins and on a method of purification of ethylene by removing olefinic impurities by means of the the same alkylation reaction removed

There are safaris for the alkylation of aromatic substances Hydrocarbons become known «Many of these processes use the classic Friedel-Crafts alkylation process, according to which the aromatic hydrocarbons are reversed of alkyl halides, alcohols or olefins in the presence of catalytically active substances are alkylated, which are now completely

generally referred to as Friedel-Crafts catalysts, e.g. >

Aluminum chloride and boron trifluoride. Although such alkylation processes >

These can be practically carried out to a large extent, as they are not phne Naohteile. When nMalioh alkylates an aromatic hydrocarbon

If, then, Aas is initially present in relation to the monoalkylation product

a further alkylation is generally far more reactive than the original »

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High Auagangematerial and eo obtained in the alkylation process the end product is a mixture of mono- and polyalkylation derivatives the hydrocarbons originally used ·· QLe subsequent Separation of the individual components of the reaction mixture ■ shares a significant difficulty inherent in the alkylation process Another procedural difficulty often arises when such an alkylation process is carried out on an industrial scale Scale is carried out. Although with alkylations on a small scale Scale also halides or alcohols with success as alkylating agents must be used in large-scale Durohftthrung essentially olefins are used * Such olefins are usually obtained in refining processes, especially in thermal or catalytic cracking process. The resulting Olefins are often impure and they consist of a mixture of the most varied Olefins together with saturated hydrocarbons and they often contain ethylene when propylene is to be used for the alkylation of aromatic hydrocarbons, for example for production of cumene from benzene. Carrying out the alkylation using such an olefin mixture entails further technical problems of concern the separation of the process product, since the usual alkylation catalysts practically no selectivity in relation to those present Show olefins and the alkylation product therefore contains derivatives of all of the olefins present in the olefins. For example arise in the alkylation of benzene by means of a propylene-ethylene mixture, usually both ethylated and propylated compounds, why the separation of the end product continues to be complicated. One must therefore ensure that the possibly existing

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Ethylen Tor carrying out an alkylation reaction with Propyltn Will get removed. Ee would therefore be of great benefit when considering a procedure cur alkylation of aromatic hydrocarbons would have made it possible to use ethylene-containing olefins, without the ethylene reacting with the alkylation, since here " a previous removal of the ethylene would be superfluous

It has now been found that the deficiencies discussed above Can be remedied by using an alkyl aluminum dichloride al · catalyst Used · Under these conditions, olefins with three or more carbon atoms in the molecule can be very effective as alkylating agents can be used without any ethylene that may be present reacting This finding is particularly surprising in view of the fact that aluminum triochloride is a well known ethylation catalyst while trialkylaluminum and dialkylaluminum chloride are not catalytic at all under the Ubliohen alkylation reduction conditions Have activity.

Accordingly, the present invention relates to a process for the alkylation of an aromatic hydrocarbon which is characterized by the fact that an aromatic hydrocarbon is used with a monoolefin with at least 3 carbon atoms in the molecule la Presence of an alkylaluminum dioloride as a catalyst.

An aromatic hydrocarbon is said to be the su-alkylating exit material are used, i.e. a compound which has at least one six-membered ring with a bensole structure.Suitable Aromatic hydrocarbons can contain up to 6 such six-membered aromatic rings, which are condensed with one another or

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may not be condensed or are bound to one another by non-aromatic hydrocarbon radicals. Aromatic RLn * ge can optionally be substituted with bia jbu 10 non-aromatic hydrocarbon radicals, which are preferably saturated and can have 1 to 8 carbonates independently of one another. Suitable substituents are, for example, alkyl or alkylene groups. The best results are obtained when the aromatic hydrocarbons which are alkylated below have only unsaturated bonds of aromatic character. Avoid aromatic coal waaaeratotffe with up to 3 six-membered aromatic rings and. to su k saturated carbon dioxide substituents which, independently of one another, can have up to bu k carbon atoms. In order to achieve particularly favorable results, it is also advantageous if at least 1 aromatic sing has at least 2 non-substituted plits. Such preventive aromatic king systems can be derived from benzene, naphthalene, antraean, phenanthrene, biphenyl and diphenylalkanes. Compounds with a single ring, ie benzene and alkyl or similar, should be particularly avoided. Alkylene derivatives of benzene, for example toluene, xylene, ethylbenzene, m-QLhexylbenzol, tetralin, o-Dlbutylbenzen, p-Od.-ootylbenzol, 1-ethyl-2, ^i- f-dipropylbenzene, pseudooumene, dur oil, cumene, ρ-isopropyltoluene m-ethylbutylbenzene. Suitable binuolear carbons are naphthalene, 1-methylnaphthalene, 2-butylnaphthalene, 1,8-bia'thylnaphthalene, 1-octylnaphthalene, 1,2,4,6-tram'thyl phthalene, biphenyl, 4-propylbiphenyl, 3, 3'-butylbiphenyl, 2,4,6-tri-t-butylbiphenyl, 2,3t3 ^t , 5 * -tetramethylbiphenyl, and k _t k '-dlieopropylbiphenyl. Diphenylalkanes, in which the aromatic rings are connected to one another by an alkylene radical with 1 to 4 carbon atoms, can also

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nen are used in the context of the invention, beiepielaweise diphenylmethane, 1,3-W.phenylbutane, 1,2-Bi- (2, ^ diaethylphenyl) -thane, 2,2-piphenylpropane and p-tolylphenylmethane. Suitable trinuolear aromatic Hydrocarbons are anthracene, 1-propylanthracene, 1,3,5,7-tetrabutylanthracene, 1,4-QLisopropylanthraoene, phenanthrene, 2,9-dimethylphenanthrene, 9-butylphenanthrene, 3,6-dioetylphenanthrene and 2,3,6,7-tetramethylphenanthrene. Also aoenaphthen, fluorene, naphthaoen, Ohrysen, Pyrene and Triphenylen eowle their alkyl derivatives can be in the frame to be used for irfinding.

Acyclic and cyclic monoolefins can be used as alkylating agents in the process according to the invention, the ethylene bond being either inside the olefin or in the bond , 2-hexene, 1-octene, 2, ^, 'f-xrimethyl-1-pentene and isomeric hones, decenes and dodenees.Suitable eyelic olefins are cyelohexene, cyelopenten, 2,3,5-trimethyloyolohexene and cyclooctene. However, the best results are obtained from aoyolic olefins which have 3 to 5 carbon atoms, whereby olefins with the ethylene bond in the end position are generally avoided compared with those with the ethylene bond in the interior of the molecule.

The method according to the invention can be carried out using the monoolefin with at least 3 carbon atoms per molecule as one olefinic Material or a mixture of olefin and ethylene can be carried out. When such a mixture of olefin and ethylene reacted the proportions of these two components are not critical, Since the process is both old mixtures, the main thing is

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must consist of such olefins with at least 3 carbon atoms also the presence of considerable amounts of ethylene is satisfactory can be carried out.

Alkylation can also be carried out without difficulty * the when the olefinic starting material inert substances as diluents contains, in particular, saturated hydrocarbons, such as χ · Β · methane, ethane and propane, which are commonly found in those from refineries originating olefins occur · It is therefore not necessary to use such diluents which do not take part in the reaction Separate alkylation from the olefin.

The choice of a particular alkyl group in the catalyst is a · set Alkylaluminiuajchlorid is not kritisoh although Alkylalumlnlumdichloride in which the alkyl group has up su 8 carbon atoms are preferred _t for their ease ZugKngliohkeit · representative of this preferred catalysts are Äthylaluniniumdiohlorid, Methylaluminiumdiohlorid, Propylalumlniumdichlorid, Butylaluminiumdiehlo · »Rid« isobutyl aluminum dichloride, hexyl aluminum dichloride, 2-ethyl · hexyl aluminum dichloride and octyl aluminum dichloride. In the context of the invention, very particular preference is given as catalyst to those alkylaluminiuradlohlorides in which the alkyl group has 2 to k carbon atoms.

The alkyl aluminum dichloride is employed in amounts ranging from 0.0001 to 0.1 moles per mole of the aromatic hydrocarbon correspond. Preferred molar ratios of catalyst to aromatic hydrocarbon are in the range between 0.01 and 0.001

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Although the method according to the invention is also used in the aaaphaa can be carried out "alkylated aan but Toreugaweiae in the liquid Phaae. Fell the aroaatiache hydrocarbon at the reaction temperature is liquid, the best results are obtained when the reaction partner is used as a reaction medium » On the other hand, the aromatic coal water falls at reaction temperature Should not be fluid, the reaction can also be inert Contain solvents, beiapielsweiae a saturated Kohlenwaaaeratoffι such as hexane, iaoootane, gyolohexane, deodorant and meowings aoleher Compounds in which the solvents are used, the aroaatiaehen Xbhlenwaaeretoff and ao the implementation of the alkylation in the flUaaigen Phaee su enable. The temperature at which the alkylation takes place, is therefore about a tone of the type de al " Raw material used aromatic hydrocarbons dependent, because in the absence of such an alkylation the alkylation becomes a moderate amount carried out. The optimal reaction temperature is also determined by the boiling point of the ala alkylating agent reacted olefin with b • That's right, because the inventive method is particularly easy carry out and check if the olefin in question «la 0 ·· Tor« lelbatTerstKndlieh, however, such a Seaktionsteapera * for use where the olefin in question is liquid Suitable reaction temperatures are also about -10 ° to 120 °, although even higher temperatures can be used. Sin · reaction temperature in the range between 20 and 100, however, precautions are taken to especially when the flavoring agent used is “carbon dioxide” single-core ·

The alkylation process according to the invention can be carried out at atmospheric sohem pressure, with negative pressure or with overpressure can be carried out. Za In general, in the pressure range Ton 0.1 to 50 atm, satisfactory Sr-

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Gebniese "rzitlt, whereby Brück" between 0.5 and 5 atm are preferred. Often the best results are obtained when during the training period Practical atmospheric pressure is applied to the use of excess pressures, it is advantageous to remove the reactor from the alkylation used olefin even under pressure, although the Presence of other inert oases, such as fltiokatoff, not harmful is, however, is preferred, the alkylation in the absence of Sau · due to the presence of greater amounts of oxygen a loss in catalysis due to oxidation of the catalyst. gate activity causes

IkLe participation participants and the catalyst can be in any Wise mixed together «Bine Ausftthrungswelse consists in that one first mixes the aromatic hydrocarbon and the catalyst and then the olefin allaMhlioh Add to this mixture, for example by adding a gaseous Introduces olefin into the coal hydrogen catalyst solution, for example. hindur pearls lM & t · However, it is just as possible that the entire Olefin is present in the reaction vessel at the beginning of the reaction · If the alkylation is carried out by means of a mixture which consists of ethylene and another olefin, then ethylene is preferably used little by little and the catalyst must first be prepared accordingly «See effect of the presence of ÄtbjjB.en see below The beginning of the implementation can not be fully explained theoretically « However, it was found that the catalyst in some Manner is deactivated and with respect to the alkylation reaction in substantial shows no more catalytic activity, but if the alkylation is first set to orange in the absence of ethylene,

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can lead to a solution in the course of the further alkylation reaction from ethylene and the other olefin can be used and the base then runs smoothly, although the ethylene does not react For the induction period of the alkylation there are no rumbling 01 «f inaengen is needed, but it is only necessary that the alkylation is checked at all ·

Kaeh completion of the reaction, the nieht uagesetsten shares de "aroaatieehen hydrocarbon and because · given * case · aitverwendete Löauagsaittel loh through to" known · MaBnahaon au · tor Beaktloaaalaehung separated, SB tillleren by eohnellea Abde- •, uad "he can then for further processing can be used again, file taxation products can then be separated from one another by fractional distillation or other known measures

What * are incurred for indproducts in the case of inventions, beatlaat «loh aui large part danaeh, in which white ·· die Alkylation is carried out regardless of the nature of the Olefin BU Kohlenwaaeeretoff eur application koaa | · case "high wall" 1 unrecognized de * cabbage «nwa * e« retoff ·· erwünaeht «ind, atteaen ent« pre * ehend high solar TerhSltni ··· τοη olefin su aroaatiaehea coals * Hydrogen can be used is blown, aan boa «« r a BonlenwaeaervtoffUbor- «Use first and only low conversion rates of the coolant hydrogen« Bine solehe low · conversion council · also does not provide any borrowing Baohteil represents, since nioht uagoweltenea Auagangeaatarial la The cycle can be carried out in the alkylation process.

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In terms of the mutual orientation of the alkyl substituents and the nature of these substituents, the usual considerations apply to the alkylation process according to the invention in the alkylation with isobutene the corresponding t-butyl derirates of the aromatic hydrocarbon are obtained. If, on the other hand, the olefinic double bond connects two secondary carbon atoms, a secondary and a primary carbon atom are connected to one another, then s-alkyl groups are introduced as sub-substituents in the aromatic hydrocarbon the alkylation with 1-butene or 2 * butene always s-butyl derivatives. Orientation of further substituents during the alkylation reaction usually takes place on the pendant carbon atom which is most electronegative, for example an orientation in ortho or para position to any alkyl substituents present - _t tri- and tetralsopropylbenzene obtained · In the alkylation of toluene or 1 «butene, according to the invention, s-butyltoluene and di-s-butyltoluene are obtained -butylnaphthalenes · The alkylation of diphenyl with cyclohexene gives mono- and polyoyolohexylated diphenyls as end products. In the alkylation of phenanthrene with isoamylene, the t-amyl derivatives of phenanthrene are obtained according to the invention.

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The alkylation products according to the invention are suggested Lttsungsaittel and for the manufacture of other valuable products * to application. For example, I leave the compound Pheael from cumene dlt produce uai p-ttLalkylbenzol can be oxidized from terephthalic acid

As a result dor fact 'ache, daft when do »orfindungageBäaen AlkyXlorungsrerfahren nioht ethylene aondern only the higher olefins react" can ea also beneficial for Beinigung τοη Äthylea been applied "coat" the new approach laaeen oieh nMalieh oleflnloehe Teruareinlgungen effective au · ethylene remove _T Index maa ias relevant olefinseaiaeh in the presence of an "alkylaluminiuadichl · rida duroh an aroaatlaehen Xbhlenwaaeoretoff hlndurehlnduret *

Sa · gate driving according to the invention is carried out during the following periods » rungabeioplele explains in more detail, weloho but not al · BeoohrXnkuag are touched.

Belepiel I

Ha reactor, which contained 15 liters of benzene, was old propylene bla au elnea pressure of 0.70 kg / oa at 25 boaufaohlagt · Kaoh Saaata Toa Io «Mol Ätaylaluainluadiohlorld aotato immediately the Beaktioa« 1 «· The Druok fell on O ab uad oa aHelen was initiated snaittalleh ·· Propylea la aoa MaA "as above was consumed · AaaohlioAoad initiated Ätayloa ami propylene old same speed, blo tor ilooriruok 1.05 kg / ea was _f geatoppt whereupon the Oaaaufuar was Trots · · elae further Zueatsea τοη h The catalyst entered koine welter · Bo * aktlon, as could be seen from the constant pressure within to · leak * tors · The oa ·· • which had accumulated over the liquid was then removed and it was seen that it was only au · Ethylea

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existed, βο that the propylene had obviously been consumed » After the ethylene had been removed, propylene was introduced again and this in turn was increased to the extent by the reaction that started again the feed is used up. The propylene feed was then interrupted and the alkylation products formed were gas-liquid » analysis of the chromatography. It was found that the reaction mixture had the following composition: ^ 8.9 wt .- # Benzolj 3 ^, 9 wt .- # cumene j 12.2 wt .- # diisopropylbenzene and ^, 0 wt .- # triisopropylbenzene. However, ethylbenzene could not be detected.

Example II

100 ml of benzene was saturated with propylene at room temperature and then 4, 5 mmol of isobutylaluminum dichloride were added After one hour of excess propylene through this The mixture was passed through, the catalyst was removed by washing and the reaction product by means of gas-fluid chromatography analyzed * It had the following composition: 96.3% weight Benzene 3.1 wt .- # cumene and 0.6 wt .- # diisopropylbenzene *

The above procedure was repeated using 1 mmole of ethylaluminum dichloride as a catalyst. The reaction product had the following composition! S3 »^ wt. 56 benzene | 9.8 percent by weight cumene 2.9 percent by weight diisopropylbenzene 2.3 percent by weight triisopropylbenzene and 1.6 percent by weight tetraisopropylbenzene.

Example III

A small reactor was filled with 100 ml of benzene and 1 mmol of ethylaluminum dichloride loaded. Then it was within a period of time

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Sound exposed to 1-butene for 20 minutes «whereby the reaction am • Chung kept at a temperature below 30 ° by cooling was · The catalyst was then removed by washing and · Beaktlonagemisoh by eaa-Jlüeeigkeits-Chromatographie and Infra « rotanalyee analyzed »One found 63, ^ Qew» - # Benzolf 26,2 aew »- # a-Butylbenzolj 10.4 Qew »- $ Bi-s-butylbenzene and traces τοη higher · * boiling material.

Example I?

Sin a dry glass flask τοη 2 l of chamfering capacity was charged with 1 l of anhydrous toluene. The flask was then purged with nitrogen and the toluene was saturated with propylene at atmospheric pressure and 25%. After adding 2 mmoles of ethyl aluminum dichloride, the temperature of the reaction mixture suddenly rose to 50 °. The propylene subsequently introduced at a rate of 900 ml / min was practically completely converted. After 2 hours of alkylation at a temperature of 30 ° and odor, the reaction rate decreased somewhat, but could be restored to the original level by adding 1 mmol of catalyst If the alkylation agent was introduced instead of pure propylene, a mixture of 600 ml / min propene and 300 ml / min ethylene was introduced immediately Propylene introduced in an amount of 900 ml / min ··· Propylene was again absorbed practically quantitatively by the reaction amieohung. "At the end of the reaction, the catalyst was removed by washing and the reaction mixture was analyzed by means of" liquidity chromatography " It found Ί2.1 α · ν .-% toluene »29 * 0 0ew.-9

Iseprepyltoluene, 20.6 Gow »- £ diisoprepyltoluene and 8.3 (3ew.-9 (Triieo-

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propyltoluene. However, ethyl-substituted reaction product could cannot be proven *

Example Y

In the alkylation of naphthalene with 1-hexene in the presence Clay octylaluminum dichloride was a mixture of mono- and di-2-hexylnaphthalene obtain.

Example YI

Isobutene was introduced into o-xylene in the presence of butylaluminum dichloride until the alkylation reaction had started was · Sann, instead of pure olefin, a mixture was made from ethylene and isobutene au, but the o-xylene only reacted selectively with the isobutene *

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Claims (1)

Claims 1 method of alkylating a β aromatic hydrocarbon β toffee, dadlirch marked that the aromatic hydrocarbon with a monoolefin having at least 3 carbon atoms in the molecule in the presence of an alkylaluminium dichloride as a catalyst is implemented « 2 · Method according to claim 1, characterized in that Ben * zol or an alkyl or alkylene derivative of benzene as aromatic Hydrocarbon is used 3 * Method according to claim 1 or 2, daduroh characterized, Aß a C, -C - alkene is used as a monoolefin 4 »Method according to claims 1 to 3 *, characterized in that a monoolefin with the olefinic double bond in the end position «in · is set. 5 »Process according to claim 1 to k _t daduroh characterized in that an alkyl aluminum dichloride is used as catalyst, the alkyl group of which contains 2 to k carbon atoms * 6. Method according to claims 1 to 5, characterized in that the alkylation is carried out at a temperature between 20 and 100 °. 7. Process according to Claims 1 to 6, characterized in that the alkylation is carried out at a pressure between 0.5 and 5 atm 909806/1009 8. The method according to claim 7, characterized in that the Alkylation is carried out essentially at atmospheric pressure. 9. The method according to claim 1 to 3, characterized in that the alkylation is carried out in the presence of ethylene « 10. The method according to claim 9, characterized in that a Mixture of the monoolefin participating in the reaction and ethylene is introduced into the alkylation zone. 11. The method according to claim 10, characterized in that the The proportion of ethylene in the mixture gradually increases from 0 to the desired end value. 12. A method for purifying ethylene, characterized in that the olefinic impurities are removed by removing the latter selectively according to the method according to claims 9 to 11 with a brings aromatic hydrocarbon to implementation. 909806/1009