DE2331163A1 - PROCESS FOR PREPARING AN ALKYLATION REACTION PRODUCT - Google Patents

Description

Dr. EMIL VORWERK ^ If ^ÖBEN _O ^ZE _T \ ^{L /} * ™ ™ ^E * June 19, 1973 PATENT Attorney MozcMr 9 · Teiefo ,, 08U2 / 6359 I 3. UUIlI W * AAA ^ 1CO Potticheckkonto ι Mfnchan 17MSf ZOO IIOO Bank ι Deutsche lank MOneh <rn, Zweigs ". Maximilians *., Account 41/9 * 236

U 813/73

Universal Oil Products Company Des Piaines, Illinois 60016 (V.St.A.)

Process for the preparation of an alkylation reaction product

The invention relates to a process for the alkylation of alkylatable isoparaffinic hydrocarbons with olefinic hydrocarbons. In particular, the invention provides a process for preparing an alkylation reaction product from an isoparaffinic reactant, a lighter olefinic reactant, and a heavier olefinic reactant using acidic alkylation catalysts. The process of the invention enables the production of alkylation reaction products with improved properties for use as a motor fuel component compared to the products produced by heretofore conventional alkylation processes.

The alkylation of isoparaffinic hydrocarbons, such as isobutane, isopentane and the like, with olefinic hydrocarbons, such as propylene, butylenes, amylenes and the like, is known to be a technically and economically important process for the production of hydrocarbons in the gasoline boiling range. The hydrocarbons generally produced by the alkylation reaction with 5 to 10 carbon atoms (for the sake of simplicity below, written analogously for all other carbon numbers as Cc-C.Q hydrocarbons) are called "alkylate"

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designated. Alkylates are because of their high engine octane numbers and Research octane numbers are particularly useful as blending components for motor fuels because they can be used to calculate the total octane number of gasolines so that they meet the requirements of modern automotive engines. Such products high octane numbers are particularly important for the production of unleaded Motor fuels of sufficient quality, if desired or required, to meet the octane rating not to use lead alkyl compounds in the fuel. It is an ongoing goal in the art to provide an isoparaffin-olefin alkylation process to provide an alkylate product of higher engine and research octane numbers than that is possible with conventional working methods.

The current trend for the imposed on motor fuel requirements and in future show expected development in this field that to strive for the production of motor fuels with Siedeendpunkten below about 150 ° C (300 ⁰ F) and / or necessary to the expected rules to meet. Conventional isoparaffin-olefin alkylation processes are not suitable for producing an alkylate product having a sufficiently low distillation endpoint to be useful in forming such low endpoint motor fuels. The process of the invention provides a procedure whereby an alkylate product can be produced having a distillation endpoint significantly lower than that possible with conventional procedures, in addition to the increased value of the product produced by the present process resulting from octane improvements.

In general, engineering uses isoparaffin-olefin alkylation processes Isobutane as isoparaffin and propylene and / or butylenes as olefins. Catalysts used include Hydrogen fluoride, sulfuric acid and other similar acidic or acidic materials. The isoparaffin, _ the olefins and the Catalysts are usually placed in an alkylation reactor

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Formation of a reaction mixture brought into contact with each other. After the alkylation reaction is essentially complete, the reaction mixture is withdrawn from the reactor and separated into a hydrocarbon phase and a catalyst phase in a separation zone, usually by settling in a sedimentation vessel, whereupon the catalyst separated in this way returned to the reactor for further use. The hydrocarbon phase produced is further processed, e.g. by fractionation to recover the alkylate product and unused reactants, e.g., isoparaffin, to further Separate use.

It has been found useful to use isoparaffin-olefin alkylation processes under very specific temperature and pressure conditions and at very specific concentrations of reactants and perform catalysts to achieve an optimal yield of high quality alkylate product. A large molar excess of isoparaffin relative to the olefin in the reaction mixture, usually from about 10: 1 to about 30: 1, represents one of the necessary conditions to achieve an at least useful product. It has proven to be useful have been found to use as great an excess of isoparaffin as possible as this improves the quality of the alkylate product will. Accordingly, there is usually a substantial amount of isoparaffin after separation from the hydrocarbon phase of the reactor effluent is recovered and returned to the reactor. The large amount of isoparaffin, which accordingly passed through the alkylation reactor and the settling vessel and unreacted to be separated from the alkylate product makes the application of high throughput fractionation units necessary to ensure adequate separation of the product alkoxide from to ensure the isoparaffin to be recycled. Limitations on the amount of excess isoparaffin applied are primarily based on economic considerations. The cost and difficulty of achieving a large throughput of isoparaffin and a large amount of isoparaffin recycle

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can at least partially by applying the method of Invention can be eliminated or reduced.

It is known that higher quality alkylate can be produced in the alkylation of olefins of different molecular weights, such as propylene and butylenes, etc., with an isoparaffin if an olefin, e.g., propylene, is separately alkylated with the isoparaffin under a set of reaction conditions while e.g. butylenes can be alkylated with the isoparaffin at a different set of reaction conditions. However, it has been found necessary to maintain the same high molar excess of isoparaffin to olefin in both the propylene alkylation reaction and the alkylation of the butylenes in order to produce a useful product. The separate alkylation of, for example, C ₃ - and C ₄ -01efinen has therefore proven to be uneconomical, in particular because of the costs for special reactors for the C -, - and C-Oiefine in connection with the aforementioned costs and difficulties of handling the large ones molar excess amounts of isoparaffin, which are necessary to achieve a high quality product.

The invention is based on the object of a simple, reliable and economical process for alkylating an isoparaffin with a lighter olefin and a heavier one To create olefin. In connection with this, the invention further aims to provide a method for producing a improved alkylation reaction product of a lighter olefin, a heavier olefin and an isoparaffin. It should an isoparaffin-olefin alkylation process can be given which manages to handle smaller amounts of isoparaffin and still has a high isoparaffin concentration during the alkylation reaction guaranteed.

The invention relates to a method for this Preparation of an alkylation reaction product from an isoparaffinic one Reactant, a lighter olefinic one

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Reactant and a heavier olefinic reactant which is characterized in that one

(a) the isoparaffinic reactant and the lighter one olefinic reactant with a first alkylation catalyst brings into contact and reacts in a first alkylation zone under first alkylation conditions,

(b) a first hydrocarbon stream from the first alkylation zone, comprising a portion of the isoparaffinic reactant and a portion of the alkylation reaction product, wins,

(c) the heavier olefinic reactant and at least a portion of the first hydrocarbon stream having a second alkylation catalyst in a second alkylation zone brings into contact with second alkylation conditions and reacts,

(d) from the second alkylation zone, a second hydrocarbon stream containing at least a portion of the alkylation reaction product includes, wins and <

(e) the alkylation reaction product from the second hydrocarbon stream wins.

The process of the invention enables separate alkylation of a lighter olefinic reactant and a heavier olefinic reactant with one Isoparaffin under different and preferred alkylation conditions for the separate alkylation of the two olefins, and it results in an improved reaction product of both olefins. At the same time, the amount of excess isoparaffin, required for optimal alkylation conditions can be reduced. By introducing the entire charge of the isoparaffinic reactant into a first Alkylation reactor along with the lighter olefinic reactant, Introducing the hydrocarbon effluent from the first reactor and the heavier olefinic reactant into a second alkylation reactor, so-like recovery

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of the alkylate product from the hydrocarbon effluent of the second alkylation reactor, the separate alkylation of the lighter and the heavier olefin with an optimal concentration of excess isoparaffin for both conversions in both reactors without the need for separate isoparaffin feeds to the two reactors used.

The attached drawing shows a flow diagram of an embodiment of the procedure. In the illustrated embodiment, isobutane is used as the isoparaffinic reactant as well as butylene and propylene used as the heavier and lighter olefinic reactants, respectively; continue to be hydrogen fluoride catalysts in both alkylation reactors used, the catalysts having different concentrations of hydrogen fluoride. However, the invention is not limited to the particular embodiment explained. Further preferred features, embodiments and examples within the scope of the invention can be found in the following explanation the drawing and preferred forms of implementation of the process emerged.

According to your flow diagram, isobutane is released through line 1 fed. The lighter olefinic reactant, the Comprises or consists of propylene, is fed through line 2 and into line i for mixing with the isobutane fed in. The mixture of propylene and isobutane continues to flow through line 1 and part of it is passed through line 3 and 4 branched off. The reactants flowing in through lines 1, 3 and 4 are separated into the alkylation reactor 5 initiated to ensure thorough mixing in the reactor 5. In the alkylation reactor 5 are the isoparaffin and the olefin with a high strength or concentration hydrogen fluoride catalyst comprising about 95% acid, brought into contact to form a reaction mixture .and thoroughly mixed. The reactor 5 is not shown with

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ORIGINAL INSPECTED

Facilities for indirect heat exchange. A Coolant is introduced through a line 6 into the reactor 5 and there with the reactants and the catalyst in indirect Brought heat exchange. The heated coolant is withdrawn from the reactor 5 through the line 7 again. The reaction mixture is at a temperature of about 32 ° C (90 ° F) and sufficient pressure to operate in reactor 5 to ensure kept in the liquid phase. The reaction mixture, the catalyst, alkylated hydrocarbons, not reacted hydrocarbons such as isobutane and possibly some propylene is withdrawn and passed through line 8 led into a sedimentation vessel 9. The hydrogen fluoride catalyst is in the settling vessel 9 high strength separated from a hydrocarbon phase, the alkylated hydrocarbons, unreacted Contains hydrocarbons and possibly smaller amounts of alkyl fluoride compounds. The hydrogen fluoride catalyst high strength forms a separate heavier phase in the settling vessel 9 and this is through the line 10 via the pump and returned to reactor 5 through line 14. A small proportion of the catalyst flowing through line 10 is higher Starch is removed through line 11 and passed to a catalyst regeneration (not shown). Fresher and / or regenerated catalyst with high hydrogen fluoride concentration, e.g. 97 weight percent, is fed through line 12 into line 10 to add the catalyst used in reactor 5 to maintain optimal strength and concentration.

From the settling vessel 9, the hydrocarbon phase is containing alkylation reaction products, isobutane and optionally some alkyl fluorides, etc. is withdrawn through line 15. The heavier olefinic reactant, the butylenes comprises or consists of it, is fed through line 16 into line 15 and with the hydrocarbons in the Line 15 mixed. The mixture of butylenes and hydrocarbon effluent from the settling vessel 9 flows on through the line 15 into the reactor 19 flowing mixture of butylenes and hydrocarbon effluent

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are branched off from line 15 into line 17 and line 18 and fed through these lines into reactor 19, to bring about thorough mixing with the alkylation catalyst in reactor 19. The reactor 19 is with not shown provided facilities for indirect heat exchange. A coolant is introduced into the reactor through line 20 introduced. The coolant is brought into indirect heat exchange with the reaction mixture located in the reactor 19 and then withdrawn through line 21. The reactants fed to the reactor 19 through lines 15, 17 and 18 are also included Lower strength hydrogen fluoride catalyst, which is about 90 percent by weight Contains acid, mixed to form a reaction mixture in the reactor 19. The reaction mixture is in the reactor 19 maintained at a temperature of about 32 ° C (90 ° F) and in the liquid phase. After the alkylation reaction essentially is complete, the reaction mixture is withdrawn from the reactor 19 and through line 22 into a reaction after or - Equalization vessel 23 (reaction soaker) in which the reaction mixture is passed is held at the alkylation temperature and pressure for a further period of time. The mixture is removed from the reaction vessel withdrawn through line 24 and fed into settling vessel 25. A heavier one separates out in the sedimentation vessel 25 the hydrogen fluoride catalyst of lesser strength existing phase and this is through the line 26 via the pump 29 and the line 30 is led back to the reactor 19. A small proportion of the catalyst flowing through the line 26 is less Starch is removed through line 27 and fed to a regeneration device, not shown. Fresher and / or regenerated catalyst is fed into line 26 through line 28. A lighter hydrocarbon phase, comprising alkylate product and unreacted isobutane is withdrawn from settler 25 through line 31 and is conventional Fractionators such as an isobutane stripping column for further conventional separation of the alkylate product and, preferably, recycling of the isobutane to reactor 5.

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Preferred features and embodiments are explained further below. Isoparaffinic and olefinic reactants, which are preferably used in the process, can be materials customary for this purpose. Isobutane is preferably used as the isoparaffin, but isopentane, isohexane and the like or a mixture of two or more isoparaffins can also be used. The isoparaffinic reactant can contain certain amounts of non-reactive accompanying substances, for example η-paraffins, without questioning its suitability. For example, a typical commercial isobutane containing certain amounts of propane and n-butane can be used as a reactant. A material comprising or consisting of butylenes is preferred as the heavier olefinic reactant. A preferred heavier olefinic reactant may, for example, contain or consist of pure butene-1, pure butene-2, pure isobutylene, or any mixture of two or all of the butylene isomers. Also well suited for use as the heavier olefinic reactants is a mixture of butylenes with certain amounts of amylenes or other heavier olefinic reactants. Other suitable heavier olefinic reactants include C ₅ and heavier olefins, although these do not necessarily give results equivalent to those obtained with C.sub.1 olefins. Preferred heavier olefinic feedstocks may contain minor amounts of other hydrocarbons such as η-paraffins, isoparaffins, ethylene, propylene, etc.

The lighter olefinic reactant is preferably propylene, which is pure propylene may or lesser amounts of paraffins, isoparaffins, ethylene, butylenes, etc. may be included. A typical commercial one Propylene reactants for the alkylation include propylene and propane. Preferably the heavier olefinic Reactants should be essentially free of the lighter olefin used, as should the lighter olefin

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Reaction participants essentially free of the one used be heavier olefin. Examples are a typical one preferred isoparaffin feed may, for example, be 95 percent by weight isobutane, 1 percent by weight propane, and 4 percent by weight n-butane contain; a typical preferred feed of the heavier olefinic reactant may, for example, be about 40 weight percent Butylenes, 45 weight percent isobutane and 15 weight percent η-butane; a typical preferred bet item of the lighter olefinic reactant can e.g. 60 percent by weight propylene and 40 percent by weight propane.

The alkylation catalysts suitable for the process include those alkylation catalysts known in the art. For example, strong acids such as hydrogen fluoride, Sulfuric acid and phosphoric acid, all have been used. Other suitable catalysts are metal halides, e.g. aluminum chloride, Antimony halides, etc., boron halides and certain crystalline aluminosilicates having catalytic activity for alkylation of isoparaffins, e.g. faujasite, mordenite, etc., either with or without the addition of catalytic amounts of metals or Metal ions.

In general, hydrogen fluoride alkylation catalysts are preferred for use in the process of the invention. Conventional hydrogen fluoride alkylation catalysts comprise about 75 weight percent or more titratable acid and about 5 percent by weight or less water, the rest consists of hydrocarbons and bound fluoride in solution in the acid. Such a conventional alkylation catalyst is useful for use both as an alkylation catalyst in the first alkylation zone for the alkylation of the isoparaffin with the lighter one olefinic reactants as well as in the second alkylation zone for use with the heavier olefinic reactant. In a particularly preferred embodiment of the process of the invention are two hydrogen fluoride catalysts different strengths used. A stronger alkylation catalyst is preferably used in the first alkylation zone

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to alkylate the isoparaffin with the lighter olefinic one Reaction part, which preferably comprises propylene, used. The stronger catalyst is characterized by a concentration of titratable acid of about 80 to about 99 percent by weight, a water content of about 0.1 to about 1 percent by weight and a hydrocarbon content of from about 1 to about 20 percent by weight. A different hydrogen fluoride alkylation catalyst the lower strength is preferred in the second alkylation reaction zone in the alkylation of the heavier olefinic reactant, which preferably comprises butylenes, used. The weaker alkylation catalyst is characterized by a titratable acid concentration of about 65 to about 95 percent by weight, a water content of about 0.1 to about 1 percent by weight and a hydrocarbon content of about 5 to about 35 weight percent. A particularly preferred higher strength catalyst contains from about 90 to about 99 weight percent Acid, a particularly preferred lower strength catalyst, contains from about 80 to about 95 weight percent acid.

Numerous alkylation reaction zones suitable for the process herein are known. Example catfish can, without limitation, the alkylation reactors described in U.S. Patents 3,456,033, 3,469,949, and 3,501,536 can be used with good success for both alkylation reactions when a fluid catalyst, e.g., the preferred Hydrogen fluoride catalyst is used. Isoparaffin-Olefin Alkylation Conditions for the alkylation reactors described in the patents listed above or in conjunction with other suitable conventional alkylation reactors are also known and can in particular embodiments The local procedure should be used. Within the scope of the invention For example, embodiments of the method in which the reactants and fluid catalysts are in the Alkylation zones are brought into contact with one another and subsequently catalyst from the reaction products by settling is separated for further use. But there are also failures

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Embodiments within the scope of the invention in which beds of solid catalysts, for example zeolitic catalysts, are used in one or both reactors and the hydrocarbon effluent from the first reactor can accordingly be passed to the second reactor without "a further separation from the catalyst Appropriate alkylation zones and optimal alkylation conditions for specific embodiments of this process will depend on the composition of the particular heavier olefinic reactant feed stream used, the particular lighter olefinic reactant feedstream used, the isoparaffin feedstream and the type of catalyst used in the preferred embodiment, isobutane and a lighter olefinic reactant which is from about 50 to about 70 volume percent propylene and from about 30 to about 50 volume percent propa n comprises, at an isobutane / propylene molar ratio of about 5: 1 to about 50: 1 with a hydrogen fluoride catalyst in a first alkylation reaction zone at alkylation conditions with a temperature ranging from about -18 to about 9 3 ° C (0 to 200 ⁰ F ), a pressure sufficient to keep the hydrocarbons and the catalyst in the liquid phase, a catalyst / hydrocarbon volume ratio in the first alkylation reactor in the range of about 0.1: 1 to about 10: 1 and a contact time (defined as the volume of the alkylation reactor divided by the volume of reaction participants and catalyst flowing in per minute) in the first alkylation reactor in the range from about 0.1 to about 30 minutes. In this preferred embodiment, a heavier olefinic reactant, which comprises about 30 to about 60 volume percent butylenes and the remainder of propane and butanes, is in a second alkylation reactor with the hydrocarbon effluent from the first alkylation zone and with a hydrogen fluoride catalyst under alkylation conditions with a temperature in the range from about -18 to about 93 ° C (0 to 200 ⁰ F), a sufficient pressure to

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ORIGINAL INSPECTED

To maintain liquid phase operation, a catalyst / hydrocarbon volume ratio in the second alkylation reactor from about 0.1: 1 to about 10: 1 and a contact time: contacted in the second alkylation reactor in the range of about 0.1 to about 30 minutes.

In a particularly preferred embodiment, the alkylation conditions in the first alkylation zone include the use of the preferred high strength hydrogen fluoride alkylation catalyst described above and a temperature of about 15 to 66 ° C (60-150 ° F), with a temperature of about 24 to 48 ° C ( 75-120 ° F) it is most preferred to have sufficient pressure to maintain the reactants and catalyst in liquid form and a reaction time of about 0.1. up to 20 minutes. Preferably, in this particular embodiment, isobutane and propylene reactants are fed to the first alkylation reactor in a molar ratio of about 20: 1 to 30: 1 and a catalyst / hydrocarbon volume ratio of about 0.5: 1 to 2: 1 is used in the first alkylation zone maintained. Further, in this particularly preferred embodiment, the alkylation conditions in the second alkylation include the use of the preferred Fluorwasserstoffalkylierungskatalysators lesser strength as described above and a temperature of about 4 to 43 ° C (40 to 110 ⁰ F), a temperature of about 10 to 38 ° C (50-100 ° F) it is most preferred to have sufficient pressure to maintain the reactants and catalyst in liquid form and a reaction time of about 0.1 to 20 minutes. Preferably, the hydrocarbon effluent from the first alkylation zone and the heavier olefinic reactant, which comprises butylenes, are fed to the second alkylation reactor with a eutylene / hydrocarbon effluent molar ratio of about 1:20 to 1:30 and a catalyst / hydrocarbon volume ratio of about 0 , 5: 1 to 2: 1 in the second alkylation reactor. If the preferred conditions specified above are observed in the first alkylation zone or the second alkylation zone, when propylene is used

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as. lighter olefinic reactant and butylenes than heavier olefinic reactant an optimal yield of high quality alkylate product from both the propylene alkylation reaction as well as the alkylation reaction of the butylenes. The desired high molar ratio of isobutane to olefins is maintained in both the first and second alkylation reaction zones without the need for it would be to have such large amounts of excess isobutane in the process as that to present separate loads of excess Isobutane would be necessary for the separate reactors according to the prior art. By taking advantage of the first Alkylation zone obtained hydrocarbons to present the hydrocarbons, in particular isobutane, in the second Alkylation zone are required, i.e. the same hydrocarbon feed in part as the excess used in both the lighter olefin alkylation reaction and in the Alkylation reaction of the heavier olefin is required. By using propylene as the lighter olefinic reactant and maintaining the above-described preferred alkylation conditions in the first alkylation zone the self-alkylation of isobutane, the c. preferred isoparaffinic Respondents, favored. Reacts under the preferred conditions used in the first alkylation zone Propylene with isobutane to form propane and isobutylene according to the hydrogen transfer reaction known in the art designated implementation. The isobutylene formed in this way reacts in an alkylation reaction with further isobutane mainly with the formation of (^ -hydrocarbons of high octane

number. Thus, albeit in the preferred embodiment of the present process, more isobutane than in some conventional ones Alkylation process may be consumed, this will be increased Consumption is more than offset by the production of additional quantities of particularly high quality alkylate product.

In the preferred embodiment, aas reaction mixture formed in the second alkylation reactor is

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ORIGINAL INSPECTED

follow-up or equalization vessel (reaction soaker). In describing the preferred embodiments given the term "second alkylation zone" excludes both the second alkylation reactor and the reaction make or equalization vessel as well as a sedimentation vessel. Suitable reaction equalization vessels are known. For example, the reaction equalization vessels U.S. Patents 3,560,587 and 3,607,970 have been used with good success in the present process Find. Such reaction equalization vessels are usually containers with perforated bottoms, Guide wall sections or the like. are equipped to that of the second Alkylation reactor fed mixture of catalyst and hydrocarbons for a predetermined period of time in the form to keep a sufficiently homogeneous mixture at the alkylation temperature and pressure. The mixture of catalyst and hydrocarbons is left in the reaction equalization vessel for a period of time that depends on the composition of the reaction mixture depends. A residence time in the reaction equalization vessel of about 1 to 30 minutes is preferred. The temperature and the pressure, which are maintained in the reaction equalization vessel are correct coincides with the temperature and pressure in the second Alkylation reactor are maintained.

Means for separating a hydrocarbon phase from, for example, a fluid catalyst phase, e.g. a hydrogen fluoride catalyst, in the effluent from an alkylation reactor or expansion tank are known in the field of alkylation. When a fluid catalyst like hydrogen fluoride Used in the present process, the effluent comprises an alkylation reactor or surge tank generally a mixture of isoparaffin, reaction products, catalyst and catalyst-soluble organic materials in combination with small amounts of olefinic compounds, light hydrocarbon gases, etc. If this mixture without Stirring and agitation is left to stand, i.e. left to settle, form the reaction products, the isoparaffin, light hydrocarbon gases and possibly some organic

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niche fluoride a hydrocarbon phase, which optionally contains a small amount of catalyst in solution. The catalyst and hydrocarbons soluble in the catalyst form one separate phase. The hydrocarbon phase can thus easily separated mechanically from the catalyst phase. The temperature and pressure conditions involved in such a settling process an alkylation process, as it is when using a fuiden Catalyst required to be complied with are essentially consistent with the alkylation reaction conditions described above for the reactor. The hydrocarbons and the catalyst become preferred during the separation process kept in the liquid phase. The term "alkylation zone" shall include a settling vessel in connection with a reactor, when a settler is required to separate the hydrocarbons from the catalyst, for example when a hydrogen fluoride catalyst is used.

Usually some means of removing heat from the alkylation zones is satisfactory Operation of the process required. There are numerous Devices for bringing about the heat deduction are known. For example can according to a preferred embodiment the - in the alkylation reaction generated heat directly from the alkylation reactor through indirect heat exchange between cooling water and the reaction time ·.:. ~ ch can be discharged into the reactor.

The hydrocarbon stream used in the preferred Embodiment from the first alkylation reactor after settling of the reaction gel discharge occurs, becomes heavier with your olefinic reactants, preferably butylenes, combined and fed to the second alkylation reactor. There this combined hydrocarbon stream is combined with an alkylation catalyst brought into contact. Usually enough isoparaffin is fed to the first reactor so that the hydrocarbons, which are fed to the second reactor, no further isoparaffin needs to be added. In general is thus the total used in alkylation processes

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BATH ORIGINAL

Isobutane successively through the first alkylation zone and the second alkylation zone passed. Under certain conditions, however, it can be advantageous to add something to the second alkylation reactor to supply further isobutane and such a modification of the procedure is within the scope of the invention. The second hydrocarbon stream, which is obtained from the second alkylation zone, is fed to other conventional separation means, e.g., a fractionator, and there the alkylate product Of unused isoparaffin and possibly entrained or dissolved catalyst, such as hydrogen fluoride, which is still in the Hydrocarbon effluent present from the second alkylation zone can be separated. Any known method of separating the alkylate product from the isoparaffin and e.g. Hydrogen fluoride find use in the process of the invention.

The alkylation produced in the process of the invention

reaction product primarily comprises saturated C-- and C _o -Coh-

lenwasserstoffe, which through the alkylation reactions of the Isoparaffins result with both the lighter and heavier olefinic reactants. To the vast majority Products include e.g. dimethylpentane and trimethylpentane. It is well known that highly branched hydrocarbons have superior properties as motor fuel; the method of the invention produces, along with other advantages, an alkylate that has a higher than usual ratio of more branched Hydrocarbons, such as trimethylpentanes, to less branched hydrocarbons such as dimethylhexanes. The invention thus creates a novel method that is used in Is able to provide an improved alkylate product after a more economical one and to produce an operationally simple way of working, compared to the previously known.

example 1

It became a mixed butylenes feed taken in stock and analyzed. It contained 50 percent by weight butene-2, 28 percent by weight isobutylene and 22 percent by weight

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BATH ORIGINAL

Butene-l. Next was "a propylene feedstock in stock." taken, it contained 99.6 percent by weight propylene by analysis. A stock of isobutane feed was also made, the Analysis showed 96 percent by weight isobutane, 3 percent by weight n-butane and 1 percent by weight propane,

An organic catalyst diluent as required for alkylation catalysts was prepared by adding 4 liters of isobutylene and 1.6-199 weight percent hydrogen fluoride to a 8.81 liter stirred autoclave under a nitrogen atmosphere of 13.4 atm (200 psi) became; the olefin and the catalyst were allowed to react at 60 ° C. for one hour and then the diluent was separated from the acid. According to analysis, the diluent comprising polyisobutylenes having a molecular weight in the range of about 200 to 500th

To demonstrate the utility and advantages of the process of the invention, a portion of the propylene feed was mixed with a portion of the isobutanein at OT.ate.r: i in an isobutane / propylene molar ratio of 24: 1. This mixture was continuously supplied to a Alkyij.sru - '^ r ^ ctor at a rate of ₁ O S moles of propylene per hour and 12 Ho;:. Iscbutar * Jv Stxinde * At the same time, a hydrogen fluoride alkylation catalyst containing 95% by weight of hydrogen fluoride, 4% by weight of organic diluent and 1% by weight of water was also continuously introduced into the reactor. The alkylation reactor was equipped with a stirrer and means for removing excess heat of reaction. An acid / hydrocarbon volume ratio of 3/2 was maintained in the reactor. The reaction mixture formed in the alkylation reactor was maintained at a temperature of 40.6 C (105 F) and a pressure of 15 atm. A residence time (defined as the volume of the reactor divided by the total volume of reactants and catalyst which was fed in per minute) of 10 minutes was also maintained. The active substance is continuously withdrawn from the alkylation reaction, passed into an acid vessel and left there for a dwell time of 5 minutes;

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the mixture separated into a catalyst phase and a hydrocarbon phase. The catalyst phase was removed and returned to the alkylation reactor for further use. The hydrocarbon phase was withdrawn from the settler and recovered. The hydrocarbons obtained in this way from the settling vessel were continuously fed to an alkylation reactor which was exactly the same as the reactor described above and used to convert the propylene. Some of the butylene feedstock mentioned at the outset was mixed with the hydrocarbon _{phase and fed continuously to the alkylation reactor at a rate of 0.5 mol of C 4} ~ olefins per hour. At the same time, a hydrogen fluoride alkylation catalyst containing 75 weight percent hydrogen fluoride, 24 weight percent organic diluent, and 1 weight percent water was also introduced into the alkylation reactor. An acid / hydrocarbon volume ratio of 3/2 was maintained in the reactor. The reaction mixture formed from the catalyst and the hydrocarbons was held at a temperature of 32 ° C (90 ° F) and a pressure of 15 atmospheres for a residence time of 10 minutes. The reaction mixture was continuously withdrawn from the alkylation reactor, passed into a settler and allowed to settle into a catalyst phase and a hydrocarbon phase. The catalyst phase was continuously removed and returned to the alkylation reactor for further use. The hydrocarbon phase was also continuously withdrawn from the settling vessel. The hydrocarbons with 5 or more carbon atoms present in the hydrocarbon phase were separated and recovered as the product of the alkylation process. Analysis of this product found a research octane number, unleaded, of 95.2 and a motor octane number, unleaded, of 92.5.

Example 2

To demonstrate the superiority of the process of the invention over other methods of alkylating isobutane with propylene and To show butylenes, another part of the same butylenes was

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oil feed as used in Example 1 with another portion of the same isobutane feed as it was was used in Example 1 in an isobutane / C. olefins molar ratio mixed by 24: 1. This mixture was continuously fed into an alkylation reactor similar to that in Example 1 reactor used was identical, at a rate of 0.5 mol of C. olefins per hour and 12 mol of isobutane per hour. At the same time, the hydrogen fluoride alkylation catalyst, the 75 weight percent hydrogen fluoride, 24 weight percent organic Containing diluent and 1 weight percent water, also continuously fed into the reactor. In the reactor was a. Maintained acid / hydrocarbon volume ratio of 3/2. The reaction mixture formed in the alkylation reactor was during a residence time of 10 minutes at a Maintained temperature of 32 C and a pressure of 15 Atm. The reaction mixture was continuously withdrawn from the alkylation reactor, passed into a settling vessel and there for a residence time held for 5 minutes, a catalyst phase and a hydrocarbon phase separated from each other. The catalyst phase was withdrawn from the settler and returned to the alkylation reactor for further use. The hydrocarbon phase was also withdrawn from the sedimentation vessel and recovered. Those obtained in this way from the sedimentation vessel Hydrocarbons were continuously fed to an alkylation reactor similar to the reactor described and used above was exactly the same. Part of the same propylene feed, as used in Example 1 was mixed with the hydrocarbons from the settler and the mixture became continuous fed to the reactor at a rate of 0.5 moles of propylene per hour. At the same time, the hydrogen fluoride alkylation catalyst was used of 95 percent by weight hydrogen fluoride, 4 percent by weight organic diluent and 1 percent by weight Water also fed continuously into the reactor. An acid / hydrocarbon volume ratio was established in the reactor maintained by 3/2. The reaction mixture formed in the alkylation reactor was during a residence time of

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10 minutes at a temperature of 40/6 ° C (105 ° F) and one Maintained pressure of 15 atm. The reaction mixture became continuous withdrawn from the alkylation reactor, passed into a settling vessel and held therein for a residence time of 5 minutes held, the reaction mixture settling into a catalyst phase and a hydrocarbon phase. The catalyst phase was continuously withdrawn from the settler and returned to the reactor for further use. The hydrocarbon phase was also continuously withdrawn from the sedimentation vessel. The hydrocarbons present in this hydrocarbon phase with 5 and more carbon atoms were separated und.as the product of the process. The analysis this product found a research unleaded octane number of 94.5 and a motor octane number, unleaded, of 92.0.

From a comparison of the octane numbers of the alkylate product obtained in Example 1 with the octane numbers of the in Example 2 obtained product is readily apparent that the process according to the invention, for which Example 1 is an embodiment represents, the procedure described in Example 2 is clearly superior, which is to be regarded as quite surprising. Although the reasons for this unexpected superiority of the alkylate product according to Example 1 over the alkylate product of the Example 2 are not fully known in detail, it may be assumed that this superiority is in part on a reduction in the quality of the alkylate formed in the first reactor of the example in the second reactor if it is in the two- » th reactor is subjected to the most favorable, relatively harsh conditions for the alkylation of propylene is. A comparison of Example 1 with Example 2 also shows that when using the first reactor for alkylation of propylene and the second reactor for alkylating butylenes, instead of reversing the order itself with identical reactors and identical reaction conditions as in Example 2, a clearly superior product according to the Process of the invention can be obtained. None of this occurs

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Increase in the consumption of reactants and auxiliary materials and the like.

Example 3

Another run was conducted to demonstrate the adaptability to optimal alkylation conditions that may be used for the alkylation of eutylenes in the process of the invention. A portion of the supply of propylene feed identified in Example 1 was combined with a portion of the supply of isobutane feed also identified in Example 1 at an isobutane / propylene molar ratio of 24: 1. The mixture of isobutane and propylene was fed to an alkylation reactor, which was the in Example 1 for the Propyler-isobutane t ^v ir>'nuation reactor used the same. The isobutane and the propylene were continuously fed to the peactor at an isobutane flow rate of 12 mol / h and a propylene flow rate of 0.5 mol / h. Hydrogen fluoride alkylation catalyst that is 95 percent by weight. Hydrogen fluoride, 4 percent by weight of organic diluent and 1 percent by weight of water were contained in the reactor. The catalyst and the hydrocarbons were brought into contact with one another to form a reaction mixture, and the reaction mixture was kept at an acid / hydrocarbon volume ratio of 3/2 for a residence time of 10 minutes at a temperature of 32 ° C. and a pressure of 15 atm. The reaction mixture was continuously withdrawn from the reactor and passed to a settling vessel in which it was left for a residence time of 5 minutes; a catalyst phase and a hydrocarbon phase formed. The catalyst phase was continuously withdrawn from the settler and returned to the reactor for further use. The hydrocarbon phase was withdrawn from the., Settling vessel and recovered. The hydrocarbons obtained in this way from a settling vessel were continuously fed to an alkylation reactor, which had the following:: · '.! basehrieber ^ n Renkte · - 3V:. · Un-

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setting of propylene and isobutane was the same. Part of the supply of the butylene feed described in Example 1 was mixed with the hydrocarbons and also continuously passed to the reactor. The butylenes were fed to the reactor at a flow rate of 0.5 mol / hour. Hydrogen fluoride alkylation catalyst, the 89 weight percent hydrogen fluoride, 9 weight percent organic diluent and Containing 1 percent by weight of water was introduced into the alkylation reactor at the same time. The hydrocarbons and the Catalysts were mixed and mixed to form a reaction mixture having an acid / hydrocarbon volume ratio of 3/2 the reaction mixture was kept at a temperature of 32 ° C. and a pressure of 15 atmospheres for a residence time of 10 minutes. The reaction mixture was continuously withdrawn from the reactor, passed to a settler and for a residence time held therein for 5 minutes, a catalyst phase and a hydrocarbon phase being formed. The catalyst phase was continuously withdrawn from the settler and returned to the reactor for further use. The hydrocarbon phase would also be withdrawn from the reactor. The hydrocarbons present in the hydrocarbon phase with Five or more carbon atoms were separated and recovered as the alkylate product. This alkylate product upon investigation revealed a research octane number, unleaded, of 96.2.

When the conditions used and the quality of the alkylate produced according to Example 1 are compared with those used Conditions and the quality of the alkylate according to Example 3 can be seen that by changing the temperatures in the first and the second reactor and by using a stronger acid in the second reactor in the example a product considerably higher quality was produced. This surprising result is particularly unexpected because the quality of the ' alkylate produced in Example 1 is already considerably higher than the quality of from the same reactants conventional methods produced alkylate, and the quality of the alkylate according to Example 1 was also significantly higher than the quality

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of alkylate, which reversed the order of the reaction of the propylene and the butylenes, as described in Example 2, was generated.

Examples 1 and 3 clearly demonstrate the wide range of conditions under which the present process, in particular the second stage of the eutylene alkylation carried out can be. By adjusting the conditions in the second, i.e., butylene, stage of the process to bring about more optimal Conditions for the alkylation of butylenes, keeping the conditions of the second stage as mild as possible, by a loss of quality in the first, i.e. the propylene alkylation stage to avoid generated alkylate, a particularly effective and advantageous process implementation is achieved »- enough. This is particularly true in comparison to carrying out an alkylation according to the method of Example 2, in the case of propylene is unset in the second stage. The propylene alkylation conditions are, in general, not as flexible as the conditions for the alkylation of butylenes. Furthermore, the propylene alkylation conditions must generally harsher than the butylene alkylation conditions to obtain a satisfactory product produce.

Example 4

The superior adaptability of the process of the invention compared to the procedure of Example 2 was further demonstrated by changing the alkylation conditions using the procedure of Example 2. A portion of the stock of the same butylene feed as used in Example 1 was used mixed with a portion of the supply of the same isobutane feed as used in Example 1. The mixture was mixed in an isobutane / butylene molar ratio of 24: 1. The mixture of isobutane and butylenes was continuously fed to an alkylation reactor, which was the same as the reactor used in Example 1, at a flow rate of 0.5 mol of butylenes and 12 Mole of isobu-

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tan per hour. Hydrogen fluoride alkylation catalyst containing 75 weight percent acid, 24 weight percent organic diluent, and 1 weight percent water was also continuously fed to the reactor. The catalyst and the hydrocarbons were mixed together in a catalyst / hydrocarbon volume ratio of 3/2. The reaction mixture was held for a residence time of 10 minutes at a temperature of 32 ° C. and a pressure of 15 atm. The reaction mixture was continuously withdrawn and passed to a settling vessel and held therein for a residence time of 5 minutes. A catalyst phase and a hydrocarbon phase settled in the process. The catalyst phase was withdrawn from the settler and returned to the reactor for further use in the butylene alkylation reaction. The hydrocarbon phase was recovered from the settler and continuously fed to an alkylation reactor similar to the reactor used in the first stage. A portion of the supply of the same propylene feed as used in Example 1 was mixed with the hydrocarbons recovered from the settler and thereby also fed into the second stage reactor at a flow rate of 0.5 mol / hr. Hydrogen fluoride catalyst containing 95 weight percent acid, 4 weight percent organic diluent, and 1 weight percent water was simultaneously continuously introduced into the second stage reactor. A catalyst / hydrocarbon volume ratio of 3/2 was maintained. The mixture of hydrocarbons and catalyst was held for a residence time of 10 minutes at a temperature of 32 ° C. and a pressure of 15 atm. The reaction mixture was continuously withdrawn from the reactor of the second stage, passed into a settling vessel and held there for a residence time * of 5 minutes. It was separated into a catalyst phase and a hydrocarbon phase and the catalyst phase was continuously withdrawn from the settling vessel and returned to the second stage reactor for further use. The hydrocarbon phase was withdrawn from the settler and fractionated. The C _g - and

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heavier hydrocarbons were replaced by the lighter hydrocarbons separated and recovered as the alkylate product of the process. Upon analysis, this alkylate product gave a research octane number unleaded, from 95.

Comparing Examples 1 and 3, in which propylene in the first stage and butylenes in the second stage were alkylated according to the process of the invention, with Examples 2 and 4, in which butylenes are alkylated in the first stage and propylene in the second stage it can be seen that the process of the invention has greater adaptability and yields a significantly superior alkylate product. In both Examples 3 and 4 Propylene was alkylated using the same temperature and acid strength and the second stage was carried out in both of these examples at a temperature of 32 ° C (90 ⁰ F). Nevertheless, the procedure of Example 3, which is an embodiment of the invention, produced a significantly superior alkylate product. By adapting the reaction conditions in Example 4, only an increase in the research octane number of 0.5 units compared to the alkylate product of Example 2 was achieved. In contrast, by adjusting the alkylation reaction conditions in Example 3, an octane number increase of a full octane number compared to the alkylate of Example 1 was achieved. Furthermore, it should be noted that - even compared to the procedure with adapted reaction conditions according to Example 4 ■ the procedure according to the invention used in Example I, which was based only on an alkylate product with an octane number at the lower end of the range achievable by the process of the invention, still gave an alkylate product which was superior to the products obtained according to the procedures of Examples 2 and 4.

Example 5

To demonstrate some of the advantages of the process of the invention over conventional methods of producing alkylate, a conventional operation was carried out. Share

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le of the stocks of propylene feed and isobuta feed, as described in Example 1, the mixture was mixed in an isobutane / propylene-Mo ratio of 12: 1. The reactants were continuously fed into an alkylation reactor fed to the in Example 1 zur'Alkylierung von. Propylene reactor used was the same. The flow rate of the reactants was kept at 6 mol / h isobutane and 0.5 mol / h propylene. Hydrogen fluoride alkylation catalyst that is 95 percent by weight Hydrogen fluoride, 4 weight percent organic diluent, and 1 weight percent water was also used fed continuously into the reactor. The hydrocarbons and the catalyst were in an acid / hydrocarbon volume ratio 'of 3/2 mixed and the reaction mixture was during a residence time of 10 minutes at a temperature of 32 ° C and a pressure of 15 atm. The reaction mixture was continuously withdrawn from the reactor and transferred to a settler directed. The reaction mixture was left in the settling vessel for a residence time of 5 minutes, in the course of which it formed a catalyst phase and a hydrocarbon phase. the Catalyst phase was drawn into the settler and returned to the reactor for further use. The hydrocarbon phase was removed from the sedimentation vessel and recovered. Proportions of butylene feed stocks described in Example 1 and the isobutane feed were combined in an isobutane / butylene molar ratio of 12: 1. These reactants were continuously fed to an alkylation reactor fed, which was the same as the reactor used for the alkylation of the butylenes in Example 1, at an isobutane flow rate of 6 mol / h and a butylene flow rate of 0.5 moles / hour. Hydrogen fluoride alkylation catalyst that is 90 percent by weight Hydrogen fluoride, 9 weight percent organic diluent, and 1 weight percent water was also used continuously fed to the reactor and with the hydrocarbon feed in an acid / hydrocarbon volume ratio united by 3/2. The resulting reaction mixture was kept at temperature for a residence time of 10 minutes

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of 32 ° C and a pressure of 15 atm. The reaction mixture was continuously withdrawn from the reactor, passed to a settling vessel and separated into a catalyst phase and a hydrocarbon phase. A residence time of 5 minutes was observed in the sedimentation vessel. The catalyst phase was continuously withdrawn from the settler and returned to the reactor for further use. The hydrocarbon phase was withdrawn from the settling vessel and combined with the hydrocarbon phase obtained from the above-mentioned propylene alkylation settling vessel. The C _g and heavier hydrocarbons of this combined hydrocarbon phase were separated from the lighter hydrocarbons and recovered as the product of the process. This alkylate product was analyzed to have a research octane number, unleaded, of 94.5.

Comparing the quality of the alkylate produced in Example 5 with the quality of that in Example 1 and Example 3 produced alkylates, it can be seen that the process of the invention can produce a significantly superior alkylate product be able to. A comparison of the amount of reactants added in Examples 1 and 3 with that in the Example 5 added amount of reactants shows that in Exactly the same amounts of reactants were used in all three examples, while essentially adhering to the same alkylation conditions in the reactors. This clearly demonstrates the superiority of the method of the invention.

Example 6

The method of the invention was further developed with conventional ones Compared alkylation methods by performing a typical conventional alkylation process in which the Propylene and butylene reactants are combined. The same propylene, butylene, and isobutane reactants became as used in example 1. The reactants were used to adjust an isobutane / propylene molar ratio of 24: 1, an isobutane / butylene molar ratio of 24: 1, and an isobutane / olefin molar ratio

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mixed at 12: 1. The reactants became continuous fed to an alkylation reactor which was the same as the reactor used in Example 1. It became a flow rate of 12 Moles / h of isobutane, 0.5 moles / h of butylenes and 0.5 moles / h of propylene are maintained. At the same time, the hydrogen fluoride catalyst the 89 weight percent acid, 10 weight percent organic diluent and containing 1 weight percent water, also fed to the reactor. In the reaction mixture, a volume ratio became from catalyst to hydrocarbons of 3/2 complied with. Again, a temperature of 32 C and a pressure of 15 atm maintained. After a residence time of 10 minutes, the reaction mixture was continuously withdrawn from the reactor, passed to a sedimentation vessel and for a dwell time of

Held in it for 5 minutes. The resulting catalyst phase was withdrawn from the settling vessel and returned to the reactor for further use. The hydrocarbon phase resulting from the settling process was withdrawn from the settling vessel and fractionated. The C ₅ and heavier hydrocarbons of the hydrocarbon phase were separated and recovered as the alkylate product of the process. This alkylate product was analyzed to have a research octane number, unleaded, of 93.5.

Comparing the alkylate product produced by the process of the invention in the Procedures of Examples 1 and 3 with that produced by the conventional alkylation method of ^! Examples

6 generated alkylate product, it can be seen that the process of the invention leads to a surprising and quite substantial improvement in the quality of the alkylate obtained , when using the same reactants in the same amounts, so produced when using identical amounts of the olefinic reactants and the Isobutane reactant, the embodiment of the process of the invention of Example 3 produced an alkylate having a research octane number of 96.2, while the conventional engineering procedure of Example 6 produced an alkylate having a research octane number of only 93.5.

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It became an operational run according to the method of the invention carried out in accordance with Example 3, the only difference was that in the second stage reactor in which the Butylene reactant was alkylated, a temperature of 20 ° C (68 ° F) was maintained, while Example 3 was a temperature of 32 ° C (90 ° F) had been applied. The hydrocarbons withdrawn from the second stage settler were in a fraction of hydrocarbons with 5 and more carbon atoms and a fraction of hydrocarbons with 4 and less Carbon atoms separated. The fraction of hydrocarbons with 5 and more carbon atoms was considered to be the alkylate product of Process won and analyzed. ' She had a research octane number of 96.2, consistent with that of the alkylate obtained by following the procedure of Example 3. This further shows flexibility in the operating conditions employed in the process of the invention for alkylating the butylenes can be.

Example 8

To further demonstrate the benefits of the process of the invention, the alkylate products produced in Examples 2, 3 and 7 were further analyzed to determine the level of C _g - and heavier hydrocarbons - produced in the embodiments of these Examples. It was found that the alkylate product produced in Examples 3 and 7 by the process of the invention contained only 4 weight percent Cg and heavier hydrocarbons, while that following the procedure of Example 2 in which only the order of reaction of the lighter and heavier was found Olefins was reversed from the sequence prescribed according to the invention, the product produced contained 6.2 percent by weight of C _g - and contained heavier hydrocarbons. The alkylate product obtained by the conventional procedures of Examples 5 and 6 was analyzed for 5 weight percent C _q and heavier hydrocarbons. There? The method of the invention thus creates a mode of operation for the spontaneous generation of alkylates which, in addition to the other advantages shown, have a boiling end point considerably below the boiling end points. Alkylates as obtained by conventional and other alkylation processes.

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Claims (13)

u-813 ^ 7331163 Claims A method of making an alkylation reaction product from an isoparaffinic reactant, one lighter olefinic reactant and one heavier olefinic reactants, characterized in that one (a) the isoparaffinic reactant and the lighter one olefinic reactant with a first alkylation catalyst in a first alkylation zone under first alkylation conditions brings into contact and implements, (b) a first hydrocarbon stream from the first alkylation zone, comprising a portion of the isoparaffinic reactant and a portion of the alkylation reaction product, wins, (c) the heavier olefinic reactant and at least part of the first hydrocarbon stream with a second Bringing alkylation catalyst into contact in a second alkylation zone at second alkylation conditions and implements, (d) a second hydrocarbon stream from the second alkylation zone, which comprises at least a portion of the alkylation reaction product, wins and (e) recovering the alkylation reaction product from the second hydrocarbon stream . 2. The method according to claim 1, characterized in that there is used as the lighter olefinic reactant propylene or a fraction comprising propylene. 3. The method according to claim 1 or 2, characterized in that there is used as the heavier olefinic reactant butylenes or a fraction comprising butylenes. 3G9884 / U40 OWGINAL INSPECT6D 4. The method according to any one of claims 1-3, characterized in that there is a first alkylation catalyst Hydrogen fluoride alkylation catalyst used. 5. The method according to any one of claims 1-4, characterized in that there is a second alkylation catalyst Hydrogen fluoride alkylation catalyst used. 6 .. The method according to claim 4 or 5, characterized in that a hydrogen fluoride alkylation catalyst is used as the first alkylation catalyst which comprises about 80 to about 99 percent by weight of hydrogen fluoride, and a temperature of about 15 to about 66 ° C ( 60 - 150 ⁰ F). 7. The method according to claim 5 or 6, characterized in that a hydrogen fluoride alkylation catalyst is used as the second alkylation catalyst which comprises about 65 to about 95 percent by weight of hydrogen fluoride, and a temperature of about -18 to about 44 ° C ( 0 - 110 ⁰ F). 8. The method according to any one of claims 1-7, characterized in that there is an isoparaffinic recycle stream the second hydrocarbon stream and at least a portion of this isoparaffinic recycle stream to the first alkylation zone introduces. 9. The method according to any one of claims 1-8, characterized in that the isoparaffinic reactant Isobutane or a fraction comprising isobutane is used. ■ 10. The method according to any one of claims 1-3, 5 and 7-9, characterized in that the first alkylation catalyst Sulfuric acid, phosphoric acid or one for isoparaffin-olefin alkylation catalytically active crystalline aluminosilicate used. 309884 / U40 originally inspected ■ - 33 - 11. The method according to any one of claims 1-4, 6 and 8 - IO, characterized in that the second alkylation catalyst Sulfuric acid, phosphoric acid or one for isoparaffin-olefin alkylation catalytically active crystalline aluminosilicate used. 12. The method according to any one of claims 6-9 and 11, characterized in that a temperature of about 24 to about 49 C (75-120 r) is maintained for the first alkylation conditions and as the first alkylation catalyst, a catalyst comprising from about 85 to about 99 weight percent hydrogen fluoride used. 13. The method according to any one of claims 7-10 and -12, characterized in that in the second alkylation conditions a temperature of about 10 to about 38 C (50- lOOT) adheres to and as a second alkylating catalyst an about 70 to about 95 weight percent hydrogen fluoride catalyst is used. 309884/1440 OfHGiNAL INSPECTED Blank page