MXPA98007213A - Alquilation process using alloying catalysts containing hidrog fluoride - Google Patents

Abstract

A feeder stack is rented in the presence of a catalyst containing hydrogen fluoride, which also comprises a carrier. Possible carriers are: a water-soluble synthetic polymer similar to sodium acrylate or a salt similar to ammonium trifluoroacetate, ammonium sulfate or ammonium methanesulfonate

Description

ALQUILATION PROCESS USING ALLOYING CATALYSTS CONTAINING HYDROGEN FLUORIDE Field of the Invention This invention relates to catalysts for the alkylation reactions and their preparation. More particularly, the invention relates to an alkylation process using an alkylation catalyst containing hydrogen fluoride, in which the catalyst can be safely and easily handled or handled, transported and stored.

BACKGROUND OF THE INVENTION Alkylation reactions are catalyzed reactions of the acid in which an alkyl group is incorporated into an organic molecule. The alkylated organic molecules, or alkylates, that result from the reaction can be used as components that. increase the octane number for formulations in gasoline or detergents.

A catalyst widely used in alkylation reactions is hydrogen fluoride. Hydrogen fluoride has the advantage that its REF. : 28376 Chemical stability processing is convenient to use for a wide range of conditions. However, hydrogen fluoride has the disadvantage that it is a volatile substance. U.S. Patent No. 5,073,674 discloses a method for decreasing the volatility of hydrogen fluoride using ammonium complexes or polyhydrogen fluoride amines. This method is undesirable due to the toxicity of the complexes. Thus, there is a need for a hydrogen fluoride alkylation catalyst that overcomes the disadvantages of both pure hydrogen fluoride and the prior art complexes.

Description of the Invention and Preferred Modalities This invention provides an alkylation process using alkylation catalysts containing hydrogen fluoride, in both liquid and solid forms. The catalyst of the invention is less hazardous than pure hydrogen fluoride and can be safely and easily stored, handled or handled and transported. In addition, methods for the preparation of alkylation catalysts containing hydrogen fluoride are provided.

The alkylation process of the invention comprises: (A) contacting an alkylation catalyst containing hydrogen fluoride, comprising an effective amount of a carrier and a catalytic amount of hydrogen fluoride, with a feeder stack under convenient conditions to form a reaction mixture comprising a hydrocarbon phase and a catalyst phase; (B) the separation of the reaction mixture of its hydrocarbon and the catalyst phase; and (C) the processing of the hydrocarbon phase to recover the alkylate. By alkylation catalyst containing hydrogen fluoride, an alkylation catalyst comprising hydrogen fluoride and a carrier is suggested.

A carrier, like that term used for purposes of this invention, is a material that is not itself a reactant in the alkylation reaction and that does not complex with hydrogen fluoride. In addition, when combined with hydrogen fluoride, the carrier serves to lower the vapor pressure of hydrogen fluoride below pure hydrogen fluoride, without altering the chemical properties of hydrogen fluoride. Suitable carriers for use in this invention include the salts of acids and polymers.

The salts of acids used as carriers are salts of acids which have a pKa value of about 7 or less, preferably about 4 or less, more preferably about 0 or less, and are soluble in hydrogen fluoride. The exemplified acids include, without limitation, carboxylic acids such as formic, propionic and trifluoroacetic acid, sulfonic acids, such as methanesulfonic acid and trifluoromethanesulfonic acid. Preferably, strong acids such as trifluoroacetic, sulfuric or sulfonic are used. The counter of the acid salt can be any counter that forms a salt with the selected acid in which the salt is soluble in hydrogen fluoride. By soluble in hydrogen fluoride it suggests that the acid salt dissolves, or form a homogeneous solution, in approximately 10 times its weight or less of hydrogen fluoride. The counter can be ammonium, alkylammonium such as tetramethyl or tetraethylammonium, or an alkali metal cation (Group IA). Exemplary salts include, without limitation, ammonium sulfate, potassium formate, sodium propionate, ammonium trifluoroacetate, and ammonium methanesulfonate. Preferably ammonium sulfate, ammonium methanesulfonate or ammonium trifluoroacetate are used.

Alternatively, the carrier can be a polymer. Homopolymers, copolymers and mixtures thereof are suggested by the term polymer. In general, the polymer used in the invention has molecular weights of about 5,000 to 10,000,000. Preferably, polymers with molecular weights of about 5,000 to an approximate 1,000,000 form are used.

The polymers used in the alkylation catalyst containing hydrogen fluoride of the invention are water soluble polymers. By "water-soluble polymer" it is suggested any molecular weight compound that swells or swells, by approximately twice its dry volume, or dissolves with the addition of water at room temperature. Preferably, the polymers used in the catalyst are polymers that swell or swell by approximately twice their dry volume with the addition of water.

Water-soluble polymers are suggested to include water-soluble semi-synthetic polymers, water-soluble synthetic polymers, and mixtures thereof. Semi-synthetic water-soluble polymers are derivatives of natural water-soluble polymers and are formed only through chemical reactions.

Examples of semi-synthetic water-soluble polymers include, without limitation, cellulose ethers, modified starches, starch derivatives, natural gum derivatives, and mixtures thereof. Illustrative water-soluble synthetic polymers include, without limitation, polymers, referred polymers, and polymer salts of acrylamide, acrylic acid, ethylene oxide, methacrylic acid, polyethylene imine, polyvinyl alcohol, polyvinyl pyrrolidone, and mixtures thereof. By referenced polymer it is suggested that the repeating unit of the polymer, or a branch thereof extending through carbon atoms, preferably one to four carbon atoms. For example, a related polymer of acrylic acid is one in which the vinyl group is extended by a carbon atom to form an allyl group.

Preferably, a synthetic polymer soluble in water is used. More preferably, the polyacrylic acid is one of the salts used. More preferably, the water soluble polymer is sodium polyacrylate.

To prepare the catalyst of the invention, an effective amount of a carrier is mixed with a catalytic amount of hydrogen fluoride. The mixing must be carried out in any suitable container resistant to corrosion. If the selected carrier is an acid salt, the acid salt is mixed and dissolved in hydrogen fluoride. If the carrier is a water-soluble polymer, the water-soluble polymer is mixed with hydrogen fluoride to form an intimate mixture. The polymer can be any form for mixing, with hydrogen fluoride including, without limitation, granules, beads, pellets, fibers or matrices. The mixing may be accompanied by any convenient means, including without limitation stirring or dispersing the polymer in a hydrogen fluoride container or passing the hydrogen fluoride gas through the polymer. Mixing is typically performed at a temperature of from about 0 to about 100 ° C, preferably from about 10 to about 40 ° C. The pressure is not critical.

When the carrier is an acid salt, an effective amount of the acid salt is any amount capable of decreasing the volatility of the hydrogen fluoride at the desired level below the pure hydrogen fluoride and which is insoluble in the catalytic amount of the hydrogen. hydrogen fluoride used. An effective amount of the polymer is an amount capable of decreasing the volatility and decreasing the surface tension of the catalytic amount of the hydrogen fluoride used in the desired amplitude. The specific amount of the salt of the acid or polymer used will depend on both the salt of the selected acid or polymer and the catalytic amount of the hydrogen fluoride used.

A catalytic amount of the hydrogen fluoride is an amount of hydrogen fluoride sufficient to maintain the desired level of the catalytic activity in the specific alkylation reaction in which it is used. If the carrier is an acid salt, the minimum amount of the hydrogen fluoride used is an amount effective either to dissolve the salt of the acid and to maintain the desired level of the catalytic activity. For polymer carriers, the minimum amount of hydrogen fluoride is an amount effective to form an intimate mixture with the polymer and maintain the desired catalytic activity.

In general, independently of the selected carrier, the amount of the hydrogen fluoride used is from 20 to about 99, preferably from about 30 to about 98, percent of the weight based on the total weight of the alkylation catalyst. For polymer / HF catalysts, more preferably from about 60 to about 99 weight percent and more preferably from about 70 to about 99 weight percent of the hydrogen fluoride are used. For HF acid salt catalysts, more preferably about 50 to 80 weight percent, more preferably about 60 to about 75 percent, of hydrogen fluoride are used. If a very similar amount of hydrogen fluoride is used, the pressure will be very low, as will the catalytic activity. If a large amount of hydrogen fluoride is used, the reduction of the vapor phase will be less, but the catalytic activity will be high. One of ordinary skill in the art will recognize that a balance preferably will be carried out between the use of also little and also large amount of hydrogen fluoride.

Without departing from the scope of the invention, it will be recognized that other components can be included in the catalysts of the invention. In general, any component that does not adversely effect the catalytic action or undesirably increase the volatility of the hydrogen fluoride can be used.

Hydrogen fluoride can be commercially available as hydrogen fluoride anhydride having a water content of 0.1% or less or aqueous hydrogen fluoride. Preferably the hydrogen fluoride anhydride is used. The salt of the acid is substantially preferably anhydride having a water content of less than about 1%. A number of substantially anhydrous acid salts are commercially available or such salts can be produced by the use of any of the well-known drying techniques such as desiccants or vacuum dryers.

If the salt of the desired acid is not readily available or is expensive, the salt of the acid can be prepared by mixing the acid with a difluoride salt to form the acid salt. Alternatively, the salt of the acid can be formed in itself by mixing together with the acid, the bifluoride salt and the hydrogen fluoride.

The catalysts may be in liquid form, gel-like solids or solids. The weight percentage of hydrogen fluoride on which the catalyst will be a liquid will depend on the carrier used. In general, for the ammonium salts of the acids having pKa's of about 3 or less, the hydrogen fluoride / alkylation catalyst of the acid salt may be liquid even with a salt content of about 20 to about 30 per cent. cent in weight. Within the range of about 5 to about 30 weight percent hydrogen fluoride, the alkylation catalyst of the hydrogen fluoride polymer will be a gel-like solid or solid, while at high concentrations of hydrogen fluoride, the catalyst more similarly . It will be a liquid.

The selection of solid, gel-like or liquid-like solid catalyst will depend on a number of factors including the specific alkylation reaction used, the scale of the reaction, and the desired procedure of mixing the product. Solid alkylation catalysts are advantageous in that they can be removed from a rented product by simple filtration or decantation. Alkylations using solid catalysts may also be susceptible by a flow system in which the materials that feed the liquid to be rented are left to downflows into a column containing the catalyst.

The catalyst of the invention can be used in conjunction with a solid support which is inert to the reaction condition of the specific alkylation reaction chosen. Suitable inert supports include, without limitation, carbon, treated fluoride or coated resins, metal calcites or halides inert to hydrogen fluoride or which can be converted to inert hydrogen fluoride compounds, and acid-resistant molecular meshes. Alternatively, an inert support can be prepared by coating a non-inert support with any suitable inert material such as antimony trifluoride or aluminum trifluoride. The supported catalyst can be prepared by any method known in the art.

The alkylation catalysts of the invention can be used in any of the well known alkylation reactions, in which the reactions are conducted over a wide range of conditions. The alkylation catalysts can be used in both vapor or liquid phase alkylation reactions. Preferably, the catalyst is used in liquid or solid form for liquid phase and solid phase reactions for vapor phase reactions. The alkylation reactions can be carried out in batch, intermittent or continuous mode.

In the process for producing an alkylate, a feeder stack is contacted with the alkylation catalyst in step (A). The used battery or feeder cells will depend on the desired alkylate. Convenient feeder cells include, without limitation, isoparaffinic or paraffinic hydrocarbons, aromatic hydrocarbons, olefins and mixtures thereof.

Examples of paraffinic or isoparaffinic hydrocarbons include without limitation, methane, butane, isobutane, isopentane, and the like. Aromatic hydrocarbons include * without limitation, benzene, alkyl benzenes, alkylene benzenes and the like. Suitable olefins for use include both olefinic hydrocarbons and olefin actinators, without limitation, alkyl halides of 3 to 5 carbon atoms, mono olefins of 3 to 6 carbon atoms, and the like. In the case of alkylation of the olefin paraffin, the molar ratio of the isoparaffin, paraffinic or aromatic hydrocarbon to olefin is used from about 1: 1 to about 1: 200, preferably from about 1: 3 to about 1:50, more preferably from about 1: 5 to about 1:25. The feeder stack may contain any cracking inhibitor or moderator known in the art.

In step (A), the feeder stack and catalyst are connected and vigorously mixed in an alkylation reactor made of any suitable material such as TEFLON® carbon steel coated under convenient conditions to form a mixture having hydrocarbon phases and catalysts . The conditions, for example, time, temperature, and pressure, are those suitable for producing the desired alkylate. The precise conditions will depend on the reaction phase, the selected feeder cell, as well as on the desired alkylate and are quickly determined by one of ordinary skill in the art. In general, the contacting step can be carried out at a temperature from about -100 ° C to about 150 ° C, preferably from about -30 ° C to about 100 ° C, more preferably from about -10 ° C to about 80 ° C and pressures from approximately 15 psi to approximately 315 psia. The contact or residence times will be from approximately 0.05 seconds to approximately several hours.

The reaction mixture formed in step (A) is separated into its hydrocarbon phase, which contains the alkylated product, and the catalyst phases in step (B). The separation can be completed by any convenient method known in the art such as distillation. The catalyst phase can be recycled again by the contact stage (A).

Following the separation, the hydrocarbon phase can be processed in one step (C) to recover the alkylated product as well as any remaining catalyst and unreacted hydrocarbon or olefin. The unreacted hydrocarbon catalyst and olefin can be recycled in step (A). Typically, processing is accompanied by any of the well-known fractional methods.

The invention will be further clarified by a consideration of the following examples which are suggested for purely exemplification.

Examples - Example 1 g of sodium polyacrylate, MW 1,000,000 were weighed into a TEFLON® autoclave coated at room temperature, and after cooling of the autoclave, on dry ice, 34.7 g of HF was charged into the autoclave to form an alkylation catalyst. solid similar to gel. The catalyst formed was 78 weight percent HF and 22 weight percent sodium polyacrylate. Subsequently the autoclave was heated to room temperature and then 40.1 g of isobutane and 20.7 g of isobutylene were added to the autoclave and then heated and maintained at 85 ° C for 1 hour during which the mixture was stirred. The reactor was then cooled and the organic liquid was analyzed by gas chromatography and mass spectrography. The analysis indicated saturated hydrocarbons of 5 to 13 carbon atoms, including isooctane.

Example 2 The procedure of Example 1 was used, except that the catalyst was 95 weight percent HF and 5 weight percent sodium polyacrylate. The resulting catalyst was a liquid phase. 29.5 g of isobutane and 20 g of isobutylene were added and reacted with the catalyst as in Example 1. Analysis of the organic liquid indicated saturated hydrocarbons of 5 to 13 carbon atoms, including isooctane. and t Example 3 36 g of HF and 4 g of polyacrylic acid copolymerized with 50 weight percent maleic acid, 5 m, weight 50,000 and available from Aldrich Chemicals were charged into an autoclave and mixed to form a 90 weight percent catalyst. HF and 10 percent by weight of the polymer. To the resulting liquid phase catalyst were added 40 g of isobutane and 20 g of Isobutylene and the mixture was heated to and maintained at 75 ° C and stirred. The reactor was cooled and the liquid phase containing the organics was analyzed by GC and MS and found to contain typical alkylation products, including isooctane. 5 Example 4 The procedure of Example 4 was used, except 0 which was 90 percent by weight HF and 10 percent by weight sodium polyacrylate copolymerized with methyl methacrylate, m, weight 15,000 and available from Aldrich Chemicals, was replaced by the catalyst of Example 3. GC and MS analysis of the liquid phase containing the organics was found to contain typical products, including ai isooctane.

Example 5 The procedure of Example-3 was followed, except that an HF of weight percent of 95 and 5 weight percent of sodium polyacrylate, m, weight, 1,000.00 catalyst and 20.5 g of propylene was substituted by isobutylen of Example 3. Analysis of the liquid phase contained in the organics by GC and MS found to contain typical alkylation products, including isooctane.

Example 6 The procedure of Example 3 was used, except that a catalyst of 95 weight percent HF and 5 weight percent sodium polyacrylate was used, weight, 1,000,000 and 20.2 g of amylene were replaced by isobutylene of Example 3. Analysis of the organic phase containing liquid by GC and MS was found to contain typical alkylation products, including isooctane.

Example v The procedure of Example 3 was used except that the catalyst which was 70 weight percent HF and 30 weight percent ammonium sulfate was used and 20 g of amylene was used for the isobutylene of Example 3. The analysis of the liquid phase containing the organics by GC and MS was found to contain typical alkylation products, including isooctane.

Example 8 g of sodium polyacrylate are weighed into a TEFLON®-coated autoclave filled at room temperature and, after cooling the autoclave on dry ice, 30 g of HF are charged into the autoclave to form a solid alkylating catalyst. The catalyst is 75 weight percent HF and 25 weight percent sodium polyacrylate. Subsequently, the autoclave was heated to room temperature and then 2: 1 of a mixture of isobutane and isobutylene was induced through the solid catalyst in the autoclave. The effluent from the autoclave is condensed in a cold trap with acetone and dry ice and the organic liquid collected is? t analyzed by GC and MS. The analysis indicated saturated hydrocarbons from 5 to 13 carbon loins present, including isooctane.

Example 9 Sodium acrylate is polymerized in the presence of the following inert solid supports: carbon, ammonium trifluoride and calcium fluoride. This results in the insertion of the solid polymer soluble in water, or supported in the inert supports. 50 g of each of these catalysts are weighed in TEFLON®-coated autoclaves at room temperature and, after cooling In the autoclaves with dry ice, 30 g of HF are loaded in each of the autoclaves to form solid alkylating catalysts. Subsequently, the autoclaves are heated to room temperature and then a 2: 1 gaseous mixture of • isobutane and isobutylene is induced through the solid catalysts in the autoclaves. The effluent from each of the condensed autoclaves in an acetone and dry ice cooled eliminator and the collected organic liquid is analyzed by GC and MS. The analysis showed the presence of saturated hydrocarbons of 5 to 13 carbon atoms, including isooctane.

Example 10 The procedure of Example 1 was used, except that the catalyst is 95 weight percent HF and 5 weight percent acrylic acid copolymerized with 10% acrylamide, 200,000 m, weight, available from Aldrich Chemicals. The resulting catalyst is a liquid phase. 29.5 g of isobutane and 20 g of isobutylene are added and reacted with the catalyst as in Example 1. Analysis of the organic liquid indicated saturated hydrocarbons of 5 to 13 carbon atoms, including isooctane.

Example 11 The procedure of Example 1 was used, except that the catalyst which is 60 weight percent HF and 40 weight percent methacrylic acid, m, weight 200,000 is used. 30 g of isobutane and 20 g of isobutylene are added and reacted with the catalyst as in Example 1. Analysis of the organic liquid indicated saturated hydrocarbons of 5 to 13 carbon atoms, including isooctane.

? »Example 12 The procedure of Example 1 was used, except that the catalyst used is 70 weight percent HF and 5 weight percent polyvinyl alcohol, m, weight 5,000. 30 g of isobutane and 20 g of isobutylan are added and reacted with the catalyst as in Example 1. Analysis of the organic liquid indicated saturated hydrocarbons of 5 to 13 carbon atoms, including 10 isooctane.

Example 13 The procedure of Example 1 was used, except that the catalyst used is 99 weight percent HF and 1 weight percent polyvinyl pyrrolidone, m, weight 1,000,000. The resulting catalyst is a liquid phase. 30 g of isobutane and 20 g of isobutylene are added and reacted with the catalyst as in Example 1. Analysis of the organic liquid indicated saturated hydrocarbons of 5 to 13 carbon atoms including isooctane. example 1 ' The procedure of Example 1 was used, except that the catalyst used is 95 weight percent HF and 5 weight percent sodium polyethylene oxide, m, weight 250,000. The resulting catalyst is a liquid phase. 29.5 g of isobutane and 20 g of isobutylene are added and reacted with the catalyst as in Example 1. Analysis of the organic liquid indicated saturated hydrocarbons of 5 to 13 carbon atoms, including isooctane.

Example 15 The procedure of Example 3 was used, except that the catalyst used which is 80 weight percent HF and 20 weight percent sodium fluoride and 20 g is used for isobutylene. The analysis of the liquid phase containing organic found to contain organic including isooctane. ^ 1 example 16 The procedure of Example 3 is used, except that the catalyst used is 20 weight percent HF and 80 weight percent sodium propionate. The analysis of the liquid phase containing the organics by GC and MS showed to contain typical alkylation products, including isooctane.

Example 17 The procedure of Example 3 was used, except that the catalyst used is 40 weight percent HF and 15 60 weight percent ammonium trifluoroacetate. The analysis of the liquid phase containing the organics by GC and MS showed to contain typical alkylation products, including isooctane.

Example 18 The procedure of Example 3 was used, except that the catalyst used is 60 weight percent HF and percent by weight of ammonium methanesulfonate. The analysis of the liquid phase containing the organics by GC and MS showed to contain typical alkylation products, including isooctane.

It is noted that, with regard to this date, the best method known by the Applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention. Having described the invention as above, the content of the following is claimed as property.

Claims (10)

1. An alkylation process characterized in that it comprises the steps of: (A) contacting a feed material with an alkylation catalyst containing hydrogen fluoride, the catalyst comprising an effective amount of a carrier and a catalytic amount of hydrogen fluoride, suitable conditions for forming a reaction mixture comprising a hydrocarbon phase, the hydrocarbon phase comprises an alkylated product, and a catalyst phase: (B) the separation of the hydrocarbon phase and the catalyst phase; Y (C) the processing of the hydrocarbon phase to recover the rented product.

2. The process according to claim 1, characterized in that the catalytic amount of the hydrogen fluoride is from about 20 to about 99 weight percent based on the total weight of the aikiazion catalyst.

3. The process according to claim 1, characterized in that the catalytic amount of the hydrogen fluoride is from about 30 to about 98 weight percent based on the total weight of the alkylation catalyst.

4. The process according to claim 1, characterized in that the carrier is a synthetic polymer soluble in water.

5. The process according to claim 4, characterized in that the synthetic water-soluble polymer is sodium polyacrylate.

6. The process according to claim 1, characterized in that it is a salt of an acid, the acid has a pKa of about 4 or less.

7. The process according to claim 6, characterized in that the salt of the acid is ammonium trifluoroacetate, ammonium sulfate, or ammonium methanesulfonate.

8. The process according to claim 1, characterized in that the feed pile comprises at least one hydrocarbon selected from the group consisting of paraffinic hydrocarbons, isoparaffin hydrocarbons, aromatic hydrocarbons, and mixtures thereof and at least one olefin selected from the group consisting of olefinic hydrocarbons, olefin-acting agents and mixtures thereof.

9. An alkylation process characterized in that it comprises the steps of: (A) contacting a feed pile comprising at least one hydrocarbon selected from the group consisting of paraffinic hydrocarbons, isoparaffin hydrocarbons, aromatic hydrocarbons, and mixtures thereof and at least an olefin selected from the group consisting of olefinic hydrocarbons, olefin-acting agents and mixtures thereof, and an alkylation catalyst containing hydrogen fluoride of from about 40 to about 1 weight percent sodium polyacrylate and from about 60 weight about 99 weight percent hydrogen fluoride, at a temperature of about -30 ° C to 100 ° C and a pressure of about 15 psia to about 315 psia for a convenient time to form a reaction mixture comprising a phase of hydrocarbon, the hydrocarbon phase comprises an alkylated product and a zador (B) The separation of the hydrocarbon phase and the catalyst phase; Y (C) the processing of the hydrocarbon phase to recover the rented product.

10. An alkylation process comprising the steps of: (A) contacting a feedstock comprising at least one hydrocarbon selected from the group consisting of paraffinic hydrocarbons isoparaffin hydrocarbons, aromatic hydrocarbons, and mixtures thereof and at least one olefin selected of the group consisting of olefinic hydrocarbons, olefin-acting agents and mixtures thereof, and an alkylation catalyst containing hydrogen fluoride of from about 50 to about 20 weight percent of an acid salt selected from the group consisting of trifluoroacetate of ammonium, sulfate of "a. * • ammonium, ammonium methanesulfonate, and mixtures thereof and . about 80 to about 80 weight percent hydrogen fluoride, at a temperature of about -30 ° C to 100 ° C and a pressure of about 5 about 15 psia at about 315 psia for a convenient time to form a reaction mixture, comprising a hydrocarbon phase, the hydrocarbon phase comprising an alkylated product and a catalyst phase; 10 (B) the separation of the hydrocarbon phase and the catalyst phase; Y (C) the processing of the hydrocarbon phase 15 to recover the alkylated product. 20 25