MXPA98006298A - Rent of benzene to form alquilbencenoslineales using mordenite that contains fl - Google Patents

Abstract

This invention is directed to a fluoride-containing mordenite catalyst and the use thereof in the manufacture of linear alkylbenzene (LAB) by alkylation of benzene with an olefin. The olefin can have from about 10 to 14 carbon atoms. The fluorine-containing mordenite is typically prepared by treatment with an aqueous solution of hydrogen fluoride. The alkylation of benzene can be carried out using reactive distillation

Description

ALOUILATION OF BENZENE TO FORM ALOÜI LINEAR BENCE? OS USING MORDENITE CONTAINING FLUORINE TECHNICAL FIELD This invention relates generally to the alkylation of benzene with olefins using mordenite catalysts.

ANTECEDENTS OF THE TECHNIQUE Linear alkylbenzenes (LAB) that have long chains (typically 10-14 carbons) are commonly used, and are commercial products. The .LAB are commonly sulfonated to thereby produce surfactants. Typically, LABs are commercially manufactured using classic Friedel-Crafts chemistry, using catalysts such as aluminum chloride, or using strong acid catalysts such as hydrogen fluoride, for example, to alkylate benzene with olefins. Although such methods produce high conversions, the selectivity to the 2-phenyl isomer, which is generally about 30% or less, is generally low. LABs with a high percentage of 2-phenyl isomer are highly desired because such compounds, when sulfonated have large "tails", which provide improved solubility and detergent properties. EP-AO 288582 discloses a process for the production of alkylated aromatic hydrocarbons, in particular dialkylated biphenyls, wherein an aromatic hydrocarbon is reacted with an olefin in the presence of a fluoride-containing mordenite zeolite catalyst, which is prepared by contacting the mordenite type zeolite with an aqueous solution of HF, with an HF concentration of 5 to 20%, or with an aqueous solution of NH4F, followed by calcination.

BRIEF DESCRIPTION OF THE INVENTION It has now been recognized that there is a need for a method for LAB production having a high olefin substrate conversion, high selectivity to the 2-phenyl isomer of LAB, and using a catalyst having long life times and ease of handling. This invention provides a solution to one or more of the problems and disadvantages described above. In its broadest aspect, this invention is a process useful for the production of monoalkylated benzene, which comprises contacting benzene with an olefin containing from about 8 to about 30 carbons in the presence of fluorine-containing mordenite, under conditions such that forms a linear monoalkylated benzene. In a second broad aspect, this invention is a process useful for the production of monoalkylated benzene, which comprises introducing a feed comprising olefin having about 8 to about 30 carbons, and benzene into a bed of fluoride-containing mordenine catalyst, under conditions such that monoalkylated benzene is produced, allow benzene, olefin and monoalkylated benzene to fall (fall) into an evaporator from a catalyst bed, remove the monoalkylated benzene from the evaporator, and heat the contents of the evaporator in such a way that the benzene is refluxed for further contact with the fluorine-containing mordenite. In another broad aspect, this invention relates to mordenite useful for alkylating benzene with olefin having a molar ratio of silica to alumina from about 10: 1 to about 100: 1; wherein the mordenite has been treated with an aqueous solution of hydrogen fluoride so that the mordenite contains from about 0.1 to about 4% fluorine by weight. In another broad aspect, this invention is a useful method for the preparation of fluorine-containing mordenite, which comprises contacting a mordenite having a molar ratio of silica to alumina in the range of from about 10: 1 to about 100: 1. , with an aqueous solution of hydrogen fluoride having a concentration of hydrogen fluoride in the range of from about 0.1 to about 10 weight percent, so that fluoride-containing mordenite is produced, the fluorine-containing mordenite is collected by filtration, and dried. The fluoride-treated mordenite catalyst advantageously produces high selectivities for the 2-phenyl isomer in the LAB preparation, which generally produces selectivities of about 70 percent or more. In addition, the fluoride-treated mordenite has a long duration time, preferably experiencing only 25 percent or less of activity decrease after 400 hours under current. A process that operates in accordance with the apparatus described in FIGS. 1 and 2 has the advantage that the ascending benzene of the evaporator continuously cleans the catalyst to thereby increase the catalyst lifetime. Furthermore, this invention advantageously produces only low amounts of dialkylated benzene, which is not particularly useful for the manufacture of detergents, as well as only low amounts of tetralin derivatives. In the present, certain terms and phrases are used that have the following meanings. "Meq / g" means milliequivalents of titratable acid per gram of catalyst, which is a unit used to describe the acidity of the catalysts. The acidity is generally determined by titration with an advance, for example by adding excessive base, for example sodium hydroxide to the catalyst and then re-titling the catalyst. "Conv." and "Conversion" means the molar percentage of a given reagent converted to product. Generally, the olefin conversion is about 95 percent or more in the practice of this invention. "Sel." and "Selectivity" means the molar percentage of a particular component in the product. Generally, the selectivity to the 2-phenyl isomer is about 70 or more in the practice of this invention. The mordenite catalyst of the present invention is useful as a catalyst in the production of LABs according to the manufacturing process of the LABs of this invention. He LAB is useful as an initial material for producing sulphonated LAB, which in itself is useful as a surfactant.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a representation of a first column of continuous reactive distillation used in the practice of this invention.

Figure 2 shows a representation of a second column of continuous reactive distillation used in the practice of this invention.

DETAILED DESCRIPTION OF THE INVENTION Preparation and properties of the catalyst The catalyst of this invention is a fluoride-containing mordenite. Mordenite is a type of zeolite. The catalyst of this invention is prepared from hydrogenated mordenite (typically having 0.1 percent or less of sodium), which has a mole ratio of silica-alumina from about 10: 1 to about 100: 1. More typically, the initial mordenite has a molar ratio of silica / alumina from about 10: 1 to about 50: 1. The initial hydrogen mordenite, which is commonly available commercially, is treated with an aqueous solution of hydrogen fluoride ("HF") to produce the active, long-lasting and highly selective catalyst of the invention. In the course of such treatment with HF, as well as during the subsequent calcination of the mordenite treated with HF, the molar ratio of silica / alumina is typically increased. The finished catalyst of this invention shows a fluorine content of from about 0.1 to about 4 weight percent, more typically about 1 percent. Although it is not desired to join any theory, it is considered that the HF reacts with sites where there are bonds -Si-O-Al- so that the bond is broken with fluorine that binds to Al so that groups are formed - Si-OH and F-A1-. This is considered to decrease the total Bronsted acid sites and increase the strength of the remaining acid sites in the mordenite, and it is considered that the acidity of the mordenite is stabilized so that the mechanisms which degrade the functioning are retarded. during the production of LABs, such as the accumulation of coke. The aqueous solution used to treat mordenite may contain a range of HF concentrations. Generally, the concentration of HF is a minimum of about 0.1 weight percent. Below such a minimum concentration, the effect of the fluorine treatment decreases significantly, resulting in an undesirable need for repeated treatment, generally the concentration of HF at the upper end is about 10 weight percent or less. Above this concentration of approximately 10 weight percent, the HF is too concentrated so that it is difficult to prevent the HF from destroying the crystallinity of the mordenite, thus damaging its effectiveness as a catalyst for the production of LAB.

An aqueous solution of HF can be prepared by diluting commercially available HF solutions of 48% to the desired concentration. Alternatively, HF can be purged in water to provide an aqueous solution of HF. Typically, the treatment is carried out by adding mordenite powder or granules to an aqueous solution of stirred HF, at a temperature from about 0 ° C to about 50 ° C. Agitation and contact are continued for a sufficient time to obtain the desired level of fluoride in the mordenite. This time may vary, based on factors such as the concentration of HF, the amount of HF solution in relation to the amount of mordenite being treated, the rate of agitation used and the temperature. After treatment, the mordenite must be recovered by filtration and then dried. It is also possible to impregnate the mordenite to an incipient wet condition with a given solution of HF, as well as to treat the mordenite with gaseous hydrogen fluoride. Preferably, the fluoride treated mordenite can be calcined in air prior to its use in alkylation service. The preferred calcination temperature will be in the range from about 400 ° C to about 600 ° C. Alternative agents for mordenite fluorination other than hydrofluoric acid and hydrogen fluoride include ammonium fluoride, fluorinated silicon compounds and fluorinated hydrocarbons.

The HF-treated mordenite of this invention generally has from about 0.1 weight percent or more of fluorine, based on the total weight of the mordenite. Typically, the fluorine-containing mordenite contains about 4 weight percent or less of fluorine. More typically, the fluorine-containing mordenite contains about 1 weight percent of fluorine. The mordenite can be used in the practice of this invention as a powder, in the form of grit, as granules or as extrudates. The mordenite can be formed into grits or extruded using binders well known to those familiar in the art, such as alumina, silica or mixtures thereof.

Reagents for the production of LAB In the practice of this invention, benzene is alkylated with olefin to form LAB. These reagents can be handled and purified as is generally performed by those familiar with the art. In this regard, it is preferred that the reagents are free of water and alcohol. The olefins used in the practice of this invention have from about 8 to about 30 carbons, preferably from about 10 to about 14 carbons, such as are commercially available or are produced as dehydrogenated paraffin raw materials. It is preferred that the olefin be monounsaturated. It is further preferred that the olefin be an alpha-olefin containing a terminal ethylenic unit. Commonly, olefins would be available in a paraffinic medium of the same carbon range. Olefins with a carbon number range of 10 to 14 will typically be available from dehydrogenation of C10 to C14 paraffin in a mixture of C10 to C14 paraffin having an olefin content of 5 to 20%. Frequently, the olefin content of the olefin-paraffin mixture would be from 8 to 10% by weight. The 2-phenyl isomer of LAB produced according to this invention is of the formula: nCH3 wherein n is from about 5 to about 17 and preferably from about 7 to about 11.

Process conditions, procedures and devices The process of this invention can be carried out using a continuous reactive distillation column shown in Figure 1. In Figure 1, a feed mixture of benzene and olefin, generally in a molar ratio of benzene to olefin ranging from about 1: 1 to 100: 1, it flows from the feed pump 10 to the feed inlet 14 via the pipe 12. The feed mixture drops to a bed 32 of packed mordenite catalyst where alkylation occurs in presence of the fluoride-containing mordenite. Alternatively, although not shown in Figure 1, benzene and olefin can be introduced separately into the bed where mixing occurs in the bed, or the reagents can be mixed by means of an in-line mixer before introducing the Reagents within the catalyst bed, or reagents can be injected separately above the bed and mixing is carried out by using standard packing above the bed, or the reagents can be purged into the chamber by above the bed. Catalyst bed 32 shown in Figure 1, on a laboratory scale, can be fabricated from two 28 mm (1.1 inch) internal diameter pipe lengths, with lengths between 24 cm (9.5 inches) and 56 cm (22 inches) . In the catalyst bed 32, the falling feed mixture also contacts the rising vapors of unreacted benzene, which has been heated to the reflux temperature in the evaporator 42 by the heater 40. Such upstream vapors pass through. on the thermocouple 38 which monitors the temperature to provide feedback to the heater 40. The ascending vapors of benzene and / or olefin also pass through the standard package 36 (e.g., 19 cm (7.5 inches) of Goodloe packaging). The rising vapors heat the thermocouple 30 which is connected to a bottom temperature controller 28 which activates the heater 40 when the temperature drops below a set level. Before start-up, the system can be flushed with nitrogen which enters via line 54 and which flows through line 58. After start-up, a nitrogen atmosphere is maintained on the system. In addition, before starting and during purging with nitrogen, it may be desirable to heat the catalyst bed 32 so that water is extracted from the fluoride containing mordenite. Waste water from the feed mixture or which otherwise enters the system, is collected in a water trap 24 by being liquefied in a condenser 21 (together with benzene vapor). If the feed is very dry (free of water), the water trap 24 may not be necessary. The removal of water leads to a longer duration of the catalyst. Therefore, the water trap 24 is optional. The same applies to Figure 2. The condenser 21 is cooled by means of a cooler such as a condenser 21 with water inlet through the orifice 22 and exiting via the orifice 20. As needed, the water in the trap 24 when the drainage valve 26 is opened. As needed, when the content of LAB in the evaporator 42 is increased to a desired level, the LAB product in the bottom can be removed from the system via line 47, using either gravity or a bottom 48 pump. to extract the product. When the product is removed in this manner, the valve 44 is opened. In Figure 1, the submerged tube 46, which is optional, is used to slightly increase the pressure in the evaporator 42 to thereby increase the boiling point of benzene one degree or two. In the same way, a pressure generator 56 can optionally be used to increase the system pressure. Other standard devices can be used to increase the pressure. In this way the pressure in the system can be increased so that the boiling point of the benzene increases by approximately 200 ° C. In Figure 1, the control mechanisms for heater inactivation 50 and pump inactivation 52 are shown which serve to inactivate the heat and the pump if the level of liquid in the system increases to such levels. These control mechanisms are optional and may be included so that the catalyst bed does not come into contact with the bottom of the evaporator. In the practice of this invention in the alkylation of benzene, a wide variety of process conditions can be used. In this regard, the temperature in the catalyst bed can vary based on the reactants, rate of introduction into the catalyst bed, size of the bed and so on. Generally, the bed is maintained at the reflux temperature of benzene, based on the pressure. Typically, the temperature of the catalyst bed is above about 70 ° C, and more likely at about 78 ° C or higher, in order to have reasonable reaction rates, and about 200 ° C or less, to avoid degradation of reagents and products, and to avoid deactivation of the catalyst by accumulation of coke. Preferably, the temperature is in the range from about 80 ° C to about 140 ° C. The process can be operated at a variety of pressures during the contact stage, with pressures from approximately atmospheric using more typically. When the process operates using a system as shown in Figures 1 and 2, the evaporator temperature is maintained so that benzene and olefin vaporize, the temperature varies based on the olefin, and is generally from about 80 ° C. up to about 250 ° C for olefins having 2 to 14 carbons. The composition of the evaporator will vary with respect to time, but is generally initially set to have a ratio of benzene to olefin of about 5: 1, maintaining this ratio during the practice of this invention. The rate of feed introduction into the catalyst bed may vary, and generally at a liquid space per hour ("LHSV") of about 0.05 μT1 to about 10 h "1, more typically from about 0.05 h" 1 to about 1 hr. 1. The molar ratio of benzene to olefin introduced into the catalyst bed is generally from about 1: 1 to about 100: 1. In commercial benzene alkylation operations, it is common to work at molar proportions from about 2: 1 to about 20: 1, which can be suitably used in the practice of this invention, and loading the olefins as an olefin-paraffin mixture comprising 5% to 20% olefin content. -paraffin are usually commercially generated through the dehydrogenation of the corresponding paraffinic starting material on a noble metal catalyst. 2 another continuous reactive distillation apparatus is shown. In Figure 2, the feed mixture enters the reactor via inlet 114. The feed mixture falls through the column of catalyst bed 132, where alkylation occurs to form LAB. A thermowell 133 monitors the temperature of the catalyst bed 132. The catalyst bed 132 may optionally be externally heated and contained within a 32 mm (1-1 / 4 inch) stainless steel pipe. The Goodloe packing is placed with the packing 136 and 137. The product LAB, as well as benzene and olefin that have not reacted, fall through the packing 136 to the evaporator 142. In the evaporator 142, the electric heater 140 heats the contents of the evaporator 142 so that the heated vapors of benzene and olefin rise from the evaporator 142 to at least reach the bed 132 of the catalyst. As needed, the LAB product at the bottom can be removed from the evaporator 142 by opening the bottom valve 144 after passing through the pipe 147 and the filter 145. The waste water from the feed mixture, or which can otherwise entering the system, it can be condensed in the condenser 121, which is cooled with a cooler by means of the inlet pipe 122 and the outlet pipe 120. The condensed water falls into the water trap 124 which can be drained as needed when the drainage valve 126 is opened. The temperature in the system is monitored by means of thermocouples 138, 130 and 165. The system includes a pressure release valve 166. A nitrogen atmosphere is maintained on the system by introducing nitrogen gas through the inlet pipe 154. The level control activator 150 activates the bottom level control valve 151 to open when the liquid level in the evaporator is increased to the level control activator 150. Although the systems shown in Figure 1 and Figure 2 show single catalyst right systems, it can be appreciated that multiple catalyst bed reactors, as well as multiple orifices for inlet feeds, water traps, are within the scope of this invention. product removal pipes and so on. In addition, the process can operate in the form of batches or in a continuous process using piston-type expense designs, drip bed designs, fluidized bed designs. It is considered that as the average molecular weight of olefins increases, particularly when the average carbon number exceeds 14, selectivity and conversion to LAB, especially LAB with isomer 2, is increasingly decreased. Alkylation product using mordenite treated with HF can be sent to a second bed of finishing catalyst to improve performance. This procedure is optional and is considered to depend on the needs and wishes of the end user. An example of such a second catalyst is HF treated clay such as montomorillonite clay having approximately 0.5% fluoride. Such a catalyst can also be adjusted to decrease the number of bromine below about 0.1., based on the conditions. The following examples are illustrative of the present invention and are not intended to limit the scope of the invention or the claims. Unless stated otherwise, all percentages are by weight. In the examples, all reagents are commercial grades and are used as received. The apparatus shown in Figure 1 is used for examples 2-4. The apparatus shown in Figure 1 is used for Example 5. It should be noted that, Example 2 illustrates the production of LAB from paraffin dehydrogenating using the fluoride-treated mordenite catalyst of Example B, where it is obtained a good catalyst life (250+ h) without catalyst regeneration, and at the same time a selectivity of LAB 2 -phenyl of >is maintained70% and high productivity of LAB, without significant loss of fluoride. On the other hand, in comparative example 1, by using untreated mordenite, without added fluoride, a rapid decrease in LAB production is shown. In addition, examples 3 and 4 illustrate the production of LAB using a 5: 1 molar C10-C14 benzene / olefin feed mixture and the fluoride-treated mordenite catalysts of example B, when operating at different LHSVs in the range 0.2-0.4 h "1. The catalyst life can exceed 500 hours. electrodeionization apparatus 10 for treatment. The molded insulator block for the electrode 28 and the electrode compartment abuts the perimeter of the faceplate 14 and the molded insulator block for the electrode 30, forms a continuous compartment of the electrode abutting the perimeter of the support plate 20. The electrodeionization apparatus 1Q has a plurality of cation permeable membranes and alternating anionic permeable membranes represented by the number 32 between the insulator block of the electrode 28 and 30. The cation permeable membranes and the anion permeable membranes 32 define the boundaries of the compartments to dilute and concentrate alternately, described.

Figure 2 representatively shows compartments for concentrating 44, 46 and a representative dilution compartment 48, between the concentration compartments, in greater detail. The membranes permeable to cations 36 and 38 and membranes permeable to A 500 g of acidified and dealuminated mordenite (CBV-20A of PQ Corp), molar ratio of Si02 / Al203 of 20, 0.02% by weight of Na20, surface area 550 m2 / g, with 1.6 mm (1/16") diameter extrudates, which have been calcined at 538 ° C overnight) add a solution of 33 ml of 48% HF solution in 1633 ml of distilled water The mixture is cooled on ice, stirred on a rotary evaporator overnight, then filtered to recover the extruded solids.The extrudates are further washed with distilled water, dried in vacuo at 100 ° C and then calcined at 538 ° C. ° C during the night The analysis of the treated mordenite shows: F: 1.2% Acidity: 0.49 meq / g EXAMPLE 1 This example illustrates the preparation of linear alkylbenzenes using a modified mordenite catalyst with hydrogen fluoride. To a 500 ml flask, prepared with a condenser and a Dean Stark trap are added 100 ml of benzene (reactive grade) plus 10 g of modified mordenite zeolite with hydrogen fluoride, prepared by the method of Example A. The mixture is subjected to at reflux for 15-20 minutes to remove small amounts of moisture, and then a combination of benzene (50 ml) plus 1-dodecene (10 g) is injected into the flask, and the solution is allowed to reflux for 3 hours. hours. After allowing to cool, the modified mordenite catalyst is removed by filtration, the filtrate is vaporized to remove the unreacted benzene, and the waste liquid is analyzed by gas chromatography. The typical analytical data are summarized in table 1.

TABLE 1 EXAMPLE 2 This example illustrates the preparation of linear alkylbenzenes from dehydrogenated paraffin using a mordenite catalyst treated with hydrogen fluoride. In the example, benzene is alkylated with a C10-C14 paraffin dehydrogenated sample containing about 8.5% C10-C14 olefins. The alkylation is carried out in a process unit as shown in figure 1. The alkylation is carried out by first charging 500 ml of a benzene / dehydrogenated paraffin mixture (10: 1 molar ratio, benzene / olefin C10- C14) to an evaporator, and 250 cc of mordenite treated with HF of Example B to a reaction zone of 2.8 cm (1.1") of internal diameter (id.) The mordenite is held in place using a Goodloe package. The evaporator is then heated to reflux and the mixture of C10-C14 paraffin benzene plus dehydrogenated (10: 1 molar ratio, benzene / C? 0-C14 olefin) is continuously introduced into the unit above the catalyst at a rate of 100 cc / h (LHSV = 0.4 h "1). Under reflux conditions, in steady state, the liquid product is continuously withdrawn from the evaporator and water is continuously withdrawn from the water trap. The crude liquid product is analyzed periodically by gas chromatography. The evaporator temperature is typically in the controlled range of 97-122 ° C. The temperature variability of the head of the column is 78-83 ° C. Table 2 shows a summary of the analytical results. After 253 hours in stream, the recovered HF-treated mordenite catalyst shows, by analysis: F 1.1% Acidity: 0.29 meq / g H20 0.3% Table 2 Comparative Example 1 This example illustrates the preparation of linear alkylbenzene from dehydrogenated paraffin using an untreated mordenite catalyst. Following the procedures of example 9, the alkylation unit was charged with 250 cc of calcined, untreated mordenite (the initial mordenite of Example B), and the liquid feed was constituted by a mixture of paraffin-C9-C14 dehydrogenated benzene. in a molar ratio of 10: 1 benzene / C10-C14 olefin. Typical results are summarized in Table 3. The recovered mordenite shows, by analysis: Acidity: 0.29 meq / g H20 2.1% Table 3 EXAMPLE 3 This example also illustrates the preparation of linear alkylbenzene from dehydrogenated paraffin using a mordenite catalyst treated with hydrogen fluoride. Following the procedures of Example 2, the alkylation unit was charged with 250 cc of the HF treated mordenite from Example B, and the fed liquid comprises a mixture of more dehydrogenated benzene C10-C14 paraffin in a molar ratio of 5: 1 of Benzene / C10-C14 olefin, the evaporator temperature typically is in the range of 122-188 ° C, the temperature of the head of the column is at 78-83 ° C. Typical analytical results are summarized in Table 4. After 503 hours in stream, the recovered HF-treated mordenite catalyst shows, by analysis: F 1.0% Acidity: 0.35 meq / g H20: 0.1% Table 4 "Corrected for benzene in the effluent sample b Applied pressure of 20.32 cm (8") of H20 cPressure applied of 30.5 cm (12") of H20 EXAMPLE 4 This example also illustrates the preparation of linear alkylbenzene from dehydrogenated paraffin using a mordenite catalyst treated with hydrogen fluoride. Following the procedures of Example 2, alkylation is carried out in a glass unit of Figure 1 complete with catalyst column, evaporator, condenser and controls. The reaction zone is charged with 500 cc of mordenite treated with HF from Example B. The liquid feed is constituted by a mixture of benzene plus dehydrogenated C10-C14 paraffin in a molar ratio of 5: 1 benzene / olefin? o_C14. The feed rate is 100 cc / h (LHSV: 0.2 h "1). Under typical steady-state reflux conditions, with an evaporator temperature in the range of 131-205 ° C and a head temperature of 76- 83 ° C, typical results are summarized in Table 5.

Table 5 "Corrected for benzene in the sample of effluent bProduct composed EXAMPLE 5 This example illustrates the preparation of linear alkylbenzenes from dehydrogenated paraffin using a mordenite catalyst treated with hydrogen fluoride. Following the procedures of Example 2, alkylation of benzene with dehydrogenated C10-C14 paraffin is carried out using the stainless steel unit of Figure 2, complete with catalyst column, evaporator, condenser and controls. Approximately 250 cc of mordenite treated with HF from Example B was charged to the column. The liquid feed constituted a mixture of benzene plus dehydrogenated C10-C14 paraffin in a molar ratio of 10: 1 benzene / C10-C14 olefin . The LHSV varies from 0.2 to 0.4 h "1. The alkylation was carried out over a column interval and evaporator temperature, and a range of outlet pressures.The typical results are summarized in Table 6.

Table 6 "Compound product bDistilled composite product Examples 6-8 These examples illustrate the preparation of linear alkyl benzene using mordenite catalysts modified with hydrogen fluoride, with different levels of fluoride treatment. Following the procedures of Example 1, the alkylation unit is charged with benzene (100 ml), a 10 g sample of modified mordenite with hydrogen fluoride prepared by the procedure of Example B, plus a mixture of benzene (50 ml) and l-decene (10 g). Three mordenites treated with HF were tested, which have the composition: Catalyst "C" 0.25% of HF in mordenite (CBV-20A) Catalyst "D" 0.50% of HF in mordenite (CBV-20A) Catalyst "E" 1.0% of HF in mordenite (CBV-20A) In each experiment, samples of the liquid from the tail or bottoms were taken at regular periods and subjected to gas chromatographic analysis. The results are summarized in Table 7.

Table 7 Example 9 This example illustrates the inactivity of a heavily charged hydrogen fluoride modified mordenite catalyst. Following the procedures of Example 2, the alkylation unit was charged with 100 ce of mordenite nail treated with hydrogen fluoride (CBV-20A) prepared by the method of Example B, but having a much higher HF load (fluoride content). , 4.8%). The acidity of the mordenite treated with HF is 0.15 meq / g. No significant amount of alkylated product was detected by gas chromatography.

Claims (15)

1. A useful process for the production of monoalkylated benzene, characterized in that it comprises: contacting the benzene with an olefin of 8 to 30 carbons in the presence of a fluoride-containing mordenite under conditions such that a monoalkylated benzene is formed; wherein the mordenite has been treated by contacting mordenite with an aqueous solution of hydrogen fluoride, wherein the hydrogen fluoride in the aqueous solution has a concentration in the range from 0.1 to 1% by weight.

2. The process according to claim 1, characterized in that the fluorine-containing mordenite has a molar ratio of silica to alumina in a range from 10: 1 to 50: 1.

3. The process according to claim 1 or 2, characterized in that the olefin has from 10 to 14 carbons.

4. The process according to claim 1, 2 or 3, characterized in that the process operates under conditions such that monoalkylated benzene contains 70 or more percent 2-phenyl isomer.

5. The process according to claim 1, 2, 3 or 4, characterized in that the mordenite contains in a range from 0.1 to 4 weight percent of fluorine.

6. The process according to claim 1, 2, 3, 4 or 5, characterized in that it further comprises: allowing benzene, olefin and monoalkylated benzene to descend to an evaporator from the catalyst bed; remove the monoalkylated benzene from the evaporator; and heating the contents of the evaporator so that the benzene is refluxed for further contact with the fluorine-containing mordenite.

7. The process according to claim 6, characterized in that the ratio of benzene to olefin in the feed is from 2: 1 to 20: 1, where the catalyst bed is maintained at a temperature of 75 ° C to 200 ° C , and where the feed is introduced into the catalyst bed at a space velocity per hour of liquid of 0.1 h "1 to lh" 1.

8. The process according to claim 1, 2, 3, 4 or 5, characterized in that the ratio of benzene to olefin is from 2: 1 to 20: 1, wherein the fluorine-containing mordenite is maintained at a temperature in the range from 75 ° C to 200 ° C, and where benzene and olefin are introduced into the fluoride-containing mordenite at a space velocity per hour of liquid from 0.1 h "1 to 1 h" 1.

9. The process according to claim 6 or 7, characterized in that it also comprises collecting the water in the vapors projecting from the upper part to the catalyst bed in a water trap.

10. Mordenite useful for renting benzene with olefin having a molar ratio of silica to alumina in a range from 10: 1 to 100: 1; wherein the mordenite is characterized in that it has been treated with an aqueous solution of hydrogen fluoride having a concentration in the range from 0.1 to 1% by weight.

11. The mordenite according to claim 10, characterized in that the molar ratio of silica to alumina is from 10: 1 to 50: 1.

12. A useful method for the preparation of fluorine-containing mordenite, characterized in that it comprises: contacting a mordenite having a molar ratio of silica to alumina in a range from 10: 1 to 100: 1 with an aqueous solution of hydrogen fluoride having a concentration of hydrogen fluoride in the range from 0.1 to 1 so that fluoride-containing mordenite is produced; collect by filtration the fluorine-containing mordenite; and drying the mordenite containing fluorine collected.

13. The method according to claim 12, characterized in that the molar ratio of silica to alumina is 50: 1 or less.

14. The method according to claim 12, or 13, characterized in that the fluorine-containing mordenite contains fluorine in the range from 0.1 to 4 weight percent.

15. The method according to claim 12, 13 or 14, characterized in that the temperature in the range from 80 ° C to 140 ° C is maintained during the contacting stage.