CN117654588A

CN117654588A - Solid acid catalyst, preparation method and application thereof

Info

Publication number: CN117654588A
Application number: CN202211033765.6A
Authority: CN
Inventors: 张成喜; 李永祥; 任奎; 付强; 周顺利
Original assignee: Sinopec Petrochemical Research Institute Co ltd; China Petroleum and Chemical Corp
Current assignee: Sinopec Petrochemical Research Institute Co ltd; China Petroleum and Chemical Corp
Priority date: 2022-08-26
Filing date: 2022-08-26
Publication date: 2024-03-08

Abstract

The invention relates to the field of catalysts, and discloses a solid acid catalyst, a preparation method and application thereof. The catalyst comprises a metal modified molecular sieve and a heat-resistant inorganic oxide; wherein the metal modified molecular sieve comprises a molecular sieve and metal outside a molecular sieve framework; the content of the metal is 8-30wt% based on the total amount of the metal modified molecular sieve; in the metal modified molecular sieve, the ratio of the mass fraction of the surface phase metal measured by XPS to the mass fraction of the bulk phase metal measured by XRF test is not more than 1.45 in terms of the mass fraction of elements. The linear chain degree of the product is obviously improved due to the shape selection of the reaction product after modification of the molecular sieve, and the service life of the catalytic alkylation cycle of the solid acid catalyst is obviously prolonged due to the improvement of the selectivity.

Description

Solid acid catalyst, preparation method and application thereof

Technical Field

The invention relates to the field of catalysts, in particular to a solid acid catalyst, a preparation method and application thereof.

Background

Long chain alkylbenzenes are important raw materials for preparing synthetic detergents sodium alkylbenzenesulfonate. In the prior art, long-chain alkylbenzene is generally prepared by alkylation reaction of long-chain olefin and benzene, and the catalyst conventionally adopted in the reaction is hydrofluoric acid or aluminum trichloride, but due to the poor safety of the two catalytic systems and the large hidden environmental protection trouble, along with the gradual increase of the requirements on industrial production safety and environmental protection, the development of a corrosion-free pollution-free catalyst is urgently needed, and the catalyst also becomes a necessary development trend of long-chain alkylbenzene production technology.

Solid acid catalyzed alkylation processes are of great interest. Currently, fluorine-containing SiO developed cooperatively for UOP and Petresa in Spain is used in commercial solid acid processes ₂ -Al ₂ O ₃ The solid acid catalyst (ZL 93104573.8) has certain corrosiveness to equipment and certain potential safety hazard due to fluorine contained in the catalyst.

In addition, zeolite molecular sieve catalyst systems are more studied at home and abroad. Because long-chain alkylbenzene molecules are relatively large, ten-membered rings and pore channels below cannot enter, only molecular sieves such as MOR, Y, beta with pore channels above ten-membered rings have good alkylation reaction catalytic performance of benzene and long-chain olefins (catalyst Surv Asia (2014) 18:1-12; catalyst Today (2017) 298:109-116). The main problems of the molecular sieve in catalyzing long-chain alkylbenzene synthesis are that the service life of the catalyst is short and the linearity of the product is low. The Y molecular sieve is widely applied to the petrochemical field and is the molecular sieve with the largest petrochemical application amount. The acid distribution and diffusion properties of the Y molecular sieve are key reasons for affecting the linear long chain olefin alkylation lifetime and product linearity.

CN107867699a discloses a Y zeolite containing regular ultra-large micropores, which is constructed by treating selected Y zeolite with a template agent and an acid and alkali, and has higher conversion rate and selectivity due to rich acid centers and proper reaction pore channels provided by the regular ultra-large micropores.

CN110562995a discloses a synthesis method of nano Y zeolite and application in synthesis of linear alkylbenzene, and because of the catalyst grain, the diffusion resistance is small, and the activity and stability of long-chain olefin alkylation are improved.

CN102639471a discloses a process for producing linear alkylbenzenes which uses a combination of two zeolites to limit skeletal isomerization to increase the linear character of the product.

Thus, alkylation of long-chain olefins with aromatics presents a significant challenge to the activity and selectivity of the reaction due to the greater length of the long-chain olefins, activation of the long-chain olefins, and skeletal isomerization.

Disclosure of Invention

The invention aims to solve the problems that a molecular sieve catalyst in the prior art has short service life and low product linearity in the catalysis of long-chain olefin alkylation reaction and is not suitable for large-scale industrial application, and provides a solid acid catalyst and a preparation method and application thereof.

In order to achieve the above object, a first aspect of the present invention provides a solid acid catalyst comprising a metal-modified molecular sieve and a refractory inorganic oxide;

Wherein the metal modified molecular sieve comprises a molecular sieve and metal outside a molecular sieve framework; the content of the metal is 8-30wt% based on the total amount of the metal modified molecular sieve;

in the metal modified molecular sieve, the ratio of the mass fraction of the surface phase metal measured by XPS to the mass fraction of the bulk phase metal measured by XRF test is not more than 1.45 in terms of the mass fraction of elements.

The second aspect of the present invention provides a method for producing a solid acid catalyst, comprising: mixing, molding and roasting a metal modified molecular sieve, a heat-resistant inorganic oxide and/or a precursor thereof, water and optionally an extrusion aid and a peptizing agent to obtain the solid acid catalyst;

The third aspect of the present invention provides a solid acid catalyst produced by the above production method.

In a fourth aspect, the present invention provides the use of a solid acid catalyst according to the first or third aspect for the preparation of long chain alkylbenzenes.

In the alkylation of linear olefins with aromatic hydrocarbons, the activation and skeletal isomerization of linear olefins present great challenges to the activity and selectivity of the reaction due to the large length of the olefins, while it is difficult to realize industrial production. The solid acid catalyst provided by the invention can realize the shape selection of a reaction product through the coordination of the metal modified molecular sieve and the heat-resistant inorganic oxide, so that the linearity of the product is obviously improved, and the selectivity of the product is improved; meanwhile, the solid acid catalyst provided by the invention is suitable for reactor forms such as a fixed bed, a fluidized bed, a moving bed and the like in industrial production, and can realize large-scale industrial application.

Drawings

FIG. 1 is an XRD spectrum of the metal-modified molecular sieve prepared in preparation example 1;

FIG. 2 is a plot of monoalkylbenzene selectivity and alkylbenzene linearity trends for the 1-dodecene and benzene alkylation reaction process of example 1.

Detailed Description

The endpoints and any values of the ranges disclosed herein are not limited to the precise range or value, and are understood to encompass values approaching those ranges or values. For numerical ranges, one or more new numerical ranges may be found between the endpoints of each range, between the endpoint of each range and the individual point value, and between the individual point value, in combination with each other, and are to be considered as specifically disclosed herein.

The first aspect of the present invention provides a solid acid catalyst comprising a metal modified molecular sieve and a refractory inorganic oxide;

In the solid acid catalyst, the metal modified molecular sieve is taken as an active component, and the inventor of the invention finds that the framework isomerization of an alkylbenzene product can be well inhibited by containing a certain amount of extra-framework metal in the molecular sieve through a great deal of research, and the linearity of the product can be further improved through the cooperation of the metal modified molecular sieve and the heat-resistant inorganic oxide, and meanwhile, the catalytic alkylation cycle life of the catalyst is also greatly prolonged, so that the catalyst is suitable for industrial production.

In the invention, the metal outside the molecular sieve framework refers to the metal which exists in the molecular sieve cation position in the form of ions and/or is loaded on the surface of the molecular sieve in the form of oxides, and the outlet peak position of the characteristic peak of the metal modified molecular sieve is the same as the outlet peak position of the diffraction peak of the unmodified molecular sieve through XRD test, namely, the characteristic peak does not deviate, so that the metal can be proved to be positioned outside the molecular sieve framework.

In the present invention, the XRD pattern was tested using an X-ray powder diffractometer from PANalytical, netherlands, under conditions including: tube voltage 40kV, tube current 40ma, cu target ka radiation, scan speed 2 °/min, scan range 2θ=5° -35 °.

In the present invention, the mass fraction of the surface phase metal means the mass fraction of the metal element obtained by XPS test, and the mass fraction of the bulk phase metal means the mass fraction of the metal element obtained by XRF test and calculation. It will be appreciated that XRF testing first yields the mass fraction of bulk metal in terms of oxide, and then calculates the mass fraction of the corresponding element.

In the present invention, XPS test was performed using an esclab 250 type X-ray photoelectron spectrometer (Thermo Fisher Scientific company), and test conditions include: monochromatic AlK alpha X-rays, energy 1486.6eV, power 150W, are used to correct charge displacement by C1s peak (284.8 eV) of polluted carbon.

In the present invention, XRF test was performed using an X-ray fluorescence spectrometer of Nippon Motor industry Co., ltd 3271; the test conditions included: the anode target material of the X-ray tube is rhodium target; the laser voltage is 50kV; the laser current was 50mA.

In the invention, the content of each component in the solid acid catalyst is calculated according to the feeding ratio, the content selection range of each component in the solid acid catalyst is wider, and the content can be adjusted according to the actual application requirement. Preferably, the dry basis mass ratio of the metal modified molecular sieve to the heat-resistant inorganic oxide is 99:1-20:80, preferably 95:5-25:75, more preferably 90:10-50:50.

In the present invention, the "dry basis mass" is defined as the mass of the catalyst after 3 hours of calcination at 600 ℃.

In the present invention, there is no particular requirement for the selection of the heat-resistant inorganic oxide, and specific species conventional in the art may be employed. Preferably, the refractory inorganic oxide is selected from at least one of alumina, zirconia, silica and titania. The adoption of the preferable heat-resistant inorganic oxide is favorable for playing the coordination effect of the metal modified molecular sieve and the heat-resistant inorganic oxide, and further improves the catalytic performance of the catalyst.

Preferably, the refractory inorganic oxide has a particle size of 0.005 to 200. Mu.m, more preferably 0.01 to 100. Mu.m. In the above preferred cases, it is advantageous to enhance the interaction of the molecular sieve with the inorganic oxide, improving catalyst performance and strength.

The inventors of the present invention creatively found that the distribution of bulk metal and surface metal has a key effect on the performance of the metal-modified molecular sieve, further affecting the catalytic performance of the solid acid catalyst, in order to further inhibit the occurrence of byproduct formation and deactivation caused by olefin isomerization, polyalkylation reaction, etc., and realize shape selective catalysis, thereby improving the linearity of the product and the cycle life of the catalyst, preferably, the ratio of the mass fraction of the surface metal measured by XPS to the mass fraction of the bulk metal measured by XRF test in the metal-modified molecular sieve is not more than 1.35, preferably 0.9-1.35, in terms of mass fraction of the element; for example, typical, but non-limiting, ratios of 0.95, 1, 1.05, 1.1, 1.15, 1.2, 1.25, 1.3, 1.35, etc. are possible. Under the above preferred distribution conditions, the service life of the solid acid catalyst and the linearity of the product are improved, and the ratio of the mass fraction of the surface phase metal to the mass fraction of the bulk phase metal is too high, which may result in shortening the catalytic life of the solid acid catalyst, and the ratio is too low, which may result in lowering the linearity of the product.

In the present invention, in order to ensure that the metal distribution is at an optimal position and thus to achieve shape selective catalysis to improve catalyst life and product linearity, it is preferable that the metal content is 12 to 23wt% in terms of elements based on the total amount of the metal-modified molecular sieve. For example, the metal content may be 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, 18wt%, 19wt%, 20wt%, 21wt%, 22wt%, 23wt% and the like, typical and non-limiting content on an elemental basis.

In the present invention, the metal preferably has an atomic radius of 120 to 270pm, preferably 160 to 240pm. Preferably, the metal is selected from at least one of alkaline earth metals, group IIIB metals, and group IIIA metals; preferably at least one of Mg, ca, sr, ba, la, ce, pr, rd, sm, eu, yb, sc, Y, al, ga and In; further preferably at least one of La, ce, sr and Y. The adoption of the preferable metal is favorable for realizing matching with a molecular sieve pore passage, achieves the optimal shape-selective catalytic effect, protects a molecular sieve structure, and further improves the service life of the catalyst and the linearity of the product.

In the present invention, preferably, the metal-modified molecular sieve is a silica-alumina molecular sieve; preferably, the molar ratio of silica/alumina in the metal modified molecular sieve is 1-100:1, further preferably 3 to 20:1.

Preferably, the metal modified molecular sieve is selected from at least one of an X-type molecular sieve, a Y-type molecular sieve, an MCM-22 type molecular sieve, a Beta-type molecular sieve and a MOR-type molecular sieve, preferably an X-type molecular sieve and/or a Y-type molecular sieve. The adoption of the preferable molecular sieve type is beneficial to further improving the catalytic activity of the solid acid catalyst.

The second aspect of the present invention provides a method for producing a solid acid catalyst, comprising: mixing, forming and roasting a metal modified molecular sieve, a heat-resistant inorganic oxide and/or a precursor thereof, water, and optionally an extrusion aid and a peptizing agent to obtain the solid acid catalyst;

In the present invention, the selection range for the content of each component in the solid acid catalyst is wide. Preferably, the mass ratio of the metal modified molecular sieve, the refractory inorganic oxide and/or the precursor thereof is 99:1-20:80, preferably 95:5-25:75, more preferably 90:10-50:50.

In the present invention, the selection range for the heat-resistant inorganic oxide is wide, and specific species conventional in the art can be employed, which are well known to those skilled in the art. Preferably, the refractory inorganic oxide is at least one selected from the group consisting of alumina, zirconia, silica and titania. The precursor of the refractory inorganic oxide is a substance that can be calcined to obtain the refractory inorganic oxide, and is also a conventional choice in the art. For example, the precursor of alumina may be pseudo-boehmite.

Preferably, the particle size of the refractory inorganic oxide and/or precursor thereof is 0.005 to 200. Mu.m, more preferably 0.01 to 100. Mu.m. In the above preferred cases, it is advantageous to enhance the interaction of the molecular sieve with the inorganic oxide, improving catalyst performance and strength.

According to the invention, the extrusion aid and/or the peptizer can be optionally added in the mixing process, and the mixing process can be selected according to actual molding requirements.

In the present invention, the kind of the extrusion aid is not particularly limited, and any extrusion aid conventional in the art is applicable to the present invention. Preferably, the extrusion aid is selected from at least one of sesbania powder, cellulose and starch.

In the invention, the selection range of the dosage of the extrusion aid is wider. Preferably, the extrusion aid is used in an amount of 0-20wt% based on the total weight of the dry basis of the metal modified molecular sieve, the heat-resistant inorganic oxide and/or the precursor thereof, and further preferably, the extrusion aid is used in an amount of 1-5wt% based on the total weight of the dry basis of the metal modified molecular sieve and the heat-resistant inorganic oxide.

In the present invention, the kind of the peptizing agent is not particularly limited, and the peptizing agent conventionally defined in the art is applicable to the present invention. Preferably, the peptizing agent is selected from at least one of citric acid, nitric acid and phosphoric acid. In the present invention, the amount of the peptizing agent is not particularly limited. Preferably, the amount of the peptizing agent is 0 to 20wt% of the total weight of the dry basis of the metal modified molecular sieve and the heat-resistant inorganic oxide and/or the precursor thereof, and further preferably, the amount of the peptizing agent is 1 to 8wt% of the total weight of the dry basis of the metal modified molecular sieve and the heat-resistant inorganic oxide and/or the precursor thereof.

In the invention, the selection range of the water consumption is wider, so long as the components can be uniformly mixed, and the water consumption can be adjusted according to actual needs. Preferably, the ratio of the amount of water to the total weight of the metal modified molecular sieve and the dry basis of the refractory inorganic oxide and/or precursor thereof is from 0.2 to 1.2:1, further preferably, the ratio of the amount of water to the total weight of the metal modified molecular sieve and the dry basis of the refractory inorganic oxide and/or precursor thereof is from 0.3 to 1:1.

In the invention, the method further comprises the steps of molding and drying the molded product to obtain a mixed molded product, and then roasting. The forming and drying may be carried out using procedures conventional in the art such that the dry basis weight of the mixed formed product is 40 to 85wt%, preferably 60 to 75wt% of the weight of the formed product.

In the present invention, it is preferable that the temperature of the molding drying is 100 to 250 ℃, preferably 100 to 150 ℃, and the time of the molding drying is 1 to 24 hours, preferably 2 to 10 hours.

Preferably, the temperature of the primary calcination is 400-650 ℃, preferably 500-600 ℃, and the time of the primary calcination is 0.5-8 hours, preferably 2-6 hours.

In the present invention, there is no particular requirement for the preparation method of the metal modified molecular sieve, as long as the above composition and structural requirements can be satisfied. Preferably, the metal modified molecular sieve is prepared by a process comprising:

(1) Subjecting the molecular sieve precursor to a first ion exchange with a first exchange liquid comprising a soluble compound of a metal;

(2) Carrying out first roasting on the product of the first ion exchange to obtain a first exchange molecular sieve;

(3) Subjecting the first exchange molecular sieve to a second ion exchange with a second exchange liquid containing a soluble compound of a metal;

(4) Subjecting the second ion exchanged product to a second calcination, optionally repeating the second ion exchange and the second calcination, to obtain a second exchanged molecular sieve;

(5) Carrying out high-temperature treatment on the second exchange molecular sieve in an oxygen-containing atmosphere to obtain the metal modified molecular sieve;

wherein the first firing and/or the second firing is performed under an alkaline atmosphere.

Through the preferred embodiment, the modification of the specific extra-framework metal can be realized through at least two-to-two baking, meanwhile, the stability of the unit cell size of the molecular sieve before and after the reaction is ensured, and the molecular sieve structure can be prevented from being damaged due to multiple baking. The solid acid catalyst prepared on the basis is applied to the preparation of long-chain alkylbenzene, and the linearity of the product can be further improved and the service life of the catalyst can be prolonged through the cooperation of the metal modified molecular sieve and the heat-resistant inorganic oxide.

In the present invention, the number of repetition of the second ion exchange and the second calcination is not particularly limited, and may be determined according to the effect of the ion exchange in order that the metal content in the molecular sieve satisfies the above range requirement, and may be repeated 1 to 3 times, for example.

According to the present invention, preferably, the molecular sieve precursor is a silica-alumina molecular sieve, and preferably, the molar ratio of silica/alumina in the molecular sieve precursor is 1 to 100:1, further preferably 3 to 20:1.

In the invention, the mole ratio of the silicon oxide and the aluminum oxide of the molecular sieve before and after metal modification is basically kept unchanged, and the requirements of the mole ratio range are met.

According to the present invention, preferably, the molecular sieve precursor is selected from at least one of an X-type molecular sieve, a Y-type molecular sieve, an MCM-22-type molecular sieve, a Beta-type molecular sieve and a MOR-type molecular sieve, preferably an X-type molecular sieve and/or a Y-type molecular sieve.

According to the present invention, preferably, the molecular sieve precursor is a molecular sieve in the hydrogen form or the sodium form.

Preferably, the molecular sieve precursor is a sodium type molecular sieve, and the first exchange liquid and/or the second exchange liquid further comprise ammonium salt. For example, the first exchange liquid contains an ammonium salt, in which case step (1) comprises ion co-exchanging the sodium molecular sieve with the first exchange liquid containing the soluble metal compound and the ammonium salt.

In the present invention, the ammonium salt may be selected conventionally in the art. Preferably, the ammonium salt is selected from at least one of ammonium nitrate, ammonium chloride and ammonium sulfate.

In the present invention, preferably, the concentration of the ammonium salt in the first exchange liquid and/or the second exchange liquid is each independently 50 to 200g/L, preferably 70 to 150g/L.

According to the present invention, when the molecular sieve precursor is a sodium type molecular sieve, preferably, the preparation method further comprises subjecting the second exchange molecular sieve to ammonium exchange with a third exchange liquid containing an ammonium salt, and then subjecting the second exchange molecular sieve to the high temperature treatment.

In the present invention, the ammonium exchange may be performed using methods and conditions conventional in the art, for example, the ammonium exchange process includes: the second exchange molecular sieve is contacted with a third exchange liquid containing ammonium salt, and then filtered and dried. The above procedure is as a single ammonium exchange operation, which can optionally be repeated 1-3 times, so that the Na mass fraction in the molecular sieve is below 0.2%.

In the present invention, the concentration of the ammonium salt in the third exchange liquid may be the same as the concentration range in the first exchange liquid or the second exchange liquid, and will not be described herein.

The soluble compound of the metal may be selected conventionally in the art according to the present invention, and is not particularly limited in the present invention. For example, the soluble compound of a metal is selected from at least one of chloride, nitrate, phosphate and sulfate of the metal.

Preferably, the first exchange liquid and the second exchange liquid each independently comprise a solvent, and the solvent is preferably water.

In the present invention, the concentration of the soluble compounds of the metals in the first exchange liquid and/or the second exchange liquid is each independently 100 to 500g/L, more preferably 130 to 400g/L.

Preferably, the metal has an atomic radius of 120-270pm, preferably 160-240pm.

In the present invention, the metal preferably has an atomic radius of 120 to 270pm, preferably 160 to 240pm. Preferably, the metal is selected from at least one of alkaline earth metals, group IIIB metals, and group IIIA metals; preferably at least one of Mg, ca, sr, ba, la, ce, pr, rd, sm, eu, yb, sc, Y, al, ga and In; further preferably at least one of La, ce, sr and Y. The adoption of the preferable metal type is favorable for realizing matching with a molecular sieve pore path, achieves the best shape-selective catalytic effect, protects a molecular sieve structure, and improves the service life of the catalyst and the linearity of the product.

According to the present invention, for the first ion exchange to be more sufficient, it is preferable that the mass ratio of the first exchange liquid to the molecular sieve precursor is 2 to 8:1, further preferably 3 to 6:1.

preferably, the mass ratio of the second exchange liquid to the first exchange molecular sieve is 3-6:1, further preferably 3 to 5:1.

In the present invention, preferably, the conditions of the first ion exchange include: the exchange temperature is 50-90 ℃, preferably 70-90 ℃; the exchange time is 0.5-2h, preferably 0.8-1.5h.

In the present invention, the conditions of the second ion exchange may be the same as or different from those of the first ion exchange, and preferably the conditions of the second ion exchange include: the exchange temperature is 50-120 ℃, preferably 70-100 ℃; the exchange time is 0.5-2h, preferably 0.8-1.5h. Preferably, the exchange temperature of the second ion exchange is 0-15 ℃, preferably 1-10 ℃, higher than the exchange temperature of the first exchange. The adoption of the preferred embodiment is beneficial to optimizing metal distribution and further improving the catalytic activity of the catalyst.

According to the present invention, it is preferable that the metal is contained in an amount of 12 to 23% by weight on an elemental basis based on the total amount of the metal-modified molecular sieve. For example, the metal may be present in an amount of 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, 18wt%, 19wt%, 20wt%, 21wt%, 22wt%, 23wt% or a value between any two points on an elemental basis. The adoption of the preferable metal content is beneficial to ensuring that the metal distribution is at the optimal position, so that the shape selective catalysis is realized, and the service life of the catalyst and the linearity of the product are improved.

In the present invention, in order to be able to further regulate the distribution of the metal, the first firing and/or the second firing are performed under an alkaline atmosphere, for example, the first firing or the second firing may be performed under an alkaline atmosphere, or both the first firing and the second firing may be performed under an alkaline atmosphere. Preferably, the first firing and the second firing are both performed under an alkaline atmosphere. By adopting the preferred embodiment, the molecular sieve structure is protected, the service life of the solid acid catalyst is further prolonged, and the linearity of the product is improved.

According to the present invention, preferably, the alkaline atmosphere is provided by an aqueous solution of an alkaline compound. It is understood that the aqueous solution of the basic compound rapidly vaporizes at the firing temperature to provide an alkaline atmosphere for the firing process.

In the present invention, the selection range for the basic compound is wide. Preferably, the basic compound is selected from at least one of ammonia, ammonium carbonate and urea, preferably ammonia.

In the present invention, preferably, the concentration of the basic compound in the aqueous solution of the basic compound is 0.01 to 2mol/L, preferably 0.01 to 0.5mol/L, further preferably 0.05 to 0.3mol/L, and in the above preferred case, the stability of the molecular sieve structure is facilitated and the cycle life of the solid acid catalyst for catalyzing the alkylation reaction is prolonged.

According to the present invention, the basic atmosphere is preferably introduced at a rate of 0.01 to 0.5mL/min, more preferably 0.05 to 0.2mL/min, relative to 50g of the molecular sieve precursor. It is understood that the rate of introduction of the basic atmosphere may be increased proportionally as the throughput of molecular sieve precursors increases.

Preferably, the conditions of the first firing include: the roasting temperature is 400-600 ℃, the roasting time is 0.5-3h, the pressure is 0.01-0.1MPa, and the pressure is gauge pressure.

Preferably, the conditions of the second firing include: the roasting temperature is 400-600 ℃, the roasting time is 0.5-3h, the pressure is 0.01-0.1MPa, and the pressure is gauge pressure.

In the present invention, the first firing and the second firing do not refer to an operation sequence, and are used only to distinguish firing conditions in different steps. The conditions of the first firing and the second firing may be the same or different as long as the above-described condition requirements are satisfied.

In the present invention, before the first roasting or the second roasting, solid-liquid separation and drying of the first ion-exchanged product or the second ion-exchanged product are further included, and the solid-liquid separation and drying may be performed by using conventional operations in the art, which are not described herein.

According to the present invention, preferably, the oxygen-containing atmosphere is air or a mixture of oxygen and an inert gas; the inert gas is preferably nitrogen.

In the present invention, preferably, the oxygen-containing atmosphere has an oxygen content of 16 to 30vol%, preferably 18 to 25vol%.

Preferably, the temperature of the high temperature treatment is 50-100 ℃ higher than the second firing temperature.

According to the present invention, preferably, the conditions of the high temperature treatment include: the temperature is 500-700 ℃, preferably 550-650 ℃, and the treatment time is 2-12h, preferably 4-8h.

The third aspect of the present invention provides a solid acid catalyst produced by the above-described production method.

In a fourth aspect, the present invention provides the use of a solid acid catalyst as described in the first or third aspect above in the preparation of a long chain alkylbenzene.

According to the invention, the solid acid catalyst is preferably suitable for the preparation of long-chain alkylbenzenes of C6-C27.

According to the invention, the solid acid catalyst is suitable for large scale industrial applications and may be adapted for any conventional reactor in the art. Preferably, the preparation of the long chain alkylbenzene is carried out in a fixed bed reactor, a fluidized bed reactor or a moving bed reactor.

The present invention will be described in detail by examples.

In the examples below, various starting materials used were commercially available and the molecular sieves used were purchased from chinese petrochemical catalyst limited, unless otherwise specified.

In the examples below, the mass fraction of bulk metal was tested by XRF. The mass fraction of the gauge phase metal was measured by XPS testing.

The testing conditions of the XRD include: the instrument used was an X-ray powder diffractometer from PANalytical, netherlands; the test conditions included: tube voltage 40kV, tube current 40ma, cu target ka radiation, scan speed 2 °/min, scan range 2θ=5° -35 °.

The following preparation examples are presented to illustrate the preparation of metal modified molecular sieves.

Preparation example 1

(1) 50g of HY molecular sieve (molar ratio of silica/alumina 6,w (Na ₂ O) =0.0628%), the first ion exchange is performed on the HY molecular sieve by using a lanthanum nitrate solution, the concentration of lanthanum nitrate is 300g/L, the exchange temperature is 80 ℃, the exchange time is 1h, and the mass ratio of the lanthanum nitrate solution to the HY molecular sieve is 3:1, filtering and drying the exchanged molecular sieve, performing first roasting at 550 ℃ for 1h under the pressure of 0.02MPa, and introducing 0.1M ammonia water at the concentration of 0.1mL/min in the roasting process; and roasting to obtain a first exchange molecular sieve, and detecting and calculating by XRF to obtain the lanthanum metal with the mass fraction of 10.65%.

(2) And (3) carrying out second ion exchange and second roasting on the first exchange molecular sieve to obtain a second exchange molecular sieve, wherein the conditions are the same as those of the step (1), and the second exchange molecular sieve is subjected to XRF detection and calculation to obtain the lanthanum metal with the mass fraction of 17.33%.

(3) And roasting the second exchange molecular sieve in the atmosphere of air in a muffle furnace at 600 ℃ for 4 hours to obtain the finished molecular sieve, wherein the number of the finished molecular sieve is Y1.

According to XRD test, as shown in figure 1, characteristic peaks at 11.9 degrees and 12.4 degrees are attributed to metal ions at cation positions, characteristic peaks at 29.0 degrees are attributed to metal oxides on the surface of the molecular sieve, meanwhile, the peak positions of the characteristic peaks of the metal modified molecular sieve are identical with the peak positions of the diffraction peaks of the HY molecular sieve, namely no offset is generated, and therefore, the metal is proved to be located outside the molecular sieve framework.

The physicochemical properties of the molecular sieve Y1 obtained by the test are shown in Table 1.

Preparation example 2

According to the method in preparation example 1, except that the HY type molecular sieve in step (1) was replaced with an equal mass of H.beta.type molecular sieve (molar ratio of silica/alumina was 19, w (Na ₂ O) =0.0171%). The number of the prepared metal modified molecular sieve is Y2.

The physicochemical properties of the molecular sieve Y2 obtained by the test are shown in Table 1.

Preparation example 3

The procedure of preparation 1 was followed except that the lanthanum nitrate solution was replaced with cerium nitrate solution. The number of the prepared metal modified molecular sieve is Y3.

The physicochemical properties of the molecular sieve Y3 obtained by the test are shown in Table 1.

Preparation example 4

The procedure of preparation 1 was followed except that the lanthanum nitrate solution was replaced with strontium nitrate solution. The number of the prepared metal modified molecular sieve is Y4.

The physicochemical properties of the molecular sieve Y4 obtained by the test are shown in Table 1.

Preparation example 5

The procedure of preparation 1 was followed, except that in both the first and second ion exchanges, the mass ratio of lanthanum nitrate solution to HY molecular sieve was 2.5:1. the number of the prepared metal modified molecular sieve is Y5.

The physicochemical properties of the molecular sieve Y5 obtained by the test are shown in Table 1.

Preparation example 6

The procedure of preparation 1 was followed, except that in both the first and second ion exchanges, the mass ratio of lanthanum nitrate solution to HY molecular sieve was 3.8:1. the number of the prepared metal modified molecular sieve is Y6.

The physicochemical properties of the molecular sieve Y6 obtained by the test are shown in Table 1.

Preparation example 7

The procedure of preparation example 1 was followed except that the flow rate of ammonia water was replaced with 0.03mL/min. The number of the prepared metal modified molecular sieve is Y7.

The physicochemical properties of the molecular sieve Y7 obtained by the test are shown in Table 1.

Preparation example 8

(1) 50g of NaY molecular sieve (molar ratio of silica/alumina 5,w (Na ₂ O) =12.8%), the NaY molecular sieve is subjected to a first ion exchange with a mixed solution of ammonium chloride and lanthanum nitrate, the concentration of ammonium chloride is 120g/L (calculated alone), the concentration of lanthanum nitrate is 300g/L (calculated alone), the exchange temperature is 80 ℃, the exchange time is 1h, and the mass ratio of the mixed solution to the molecular sieve is 3:1, filtering and drying the exchanged molecular sieve, performing first roasting at 550 ℃ for 1h under the pressure of 0.02MPa, and introducing 0.1M ammonia water at the concentration of 0.1mL/min in the roasting process; and roasting to obtain the first exchange molecular sieve.

(2) And (3) carrying out second ion exchange and second roasting on the first exchange molecular sieve to obtain a second exchange molecular sieve, wherein the conditions are the same as those of the step (1).

(3) And exchanging the second exchange molecular sieve by adopting an ammonium chloride solution, wherein the concentration of ammonium chloride is 120g/L, the exchange temperature is 80 ℃, the exchange time is 1h, and the mass ratio of the ammonium chloride solution to the molecular sieve is 3: and 1, filtering and drying the exchanged molecular sieve, then exchanging ammonium chloride solution again, repeating the process for 2 times under the same conditions as the above, so that the Na mass fraction in the molecular sieve is lower than 0.2%, and roasting the second exchanged molecular sieve in a muffle furnace at 600 ℃ for 4 hours in the air atmosphere.

The finished molecular sieve is the molecular sieve with the number of Y8. The physicochemical properties of the molecular sieve Y8 obtained by the test are shown in Table 1.

Preparation example 9

The procedure of preparation 1 was followed, except that the concentration of the lanthanum nitrate solution was 400g/L. The number of the prepared metal modified molecular sieve is Y9.

The physicochemical properties of the molecular sieve Y9 obtained by the test are shown in the following Table 1.

Preparation example 10

The procedure of preparation 1 was followed, except that the concentration of the lanthanum nitrate solution was 200g/L. The number of the prepared metal modified molecular sieve is Y10.

The physicochemical properties of the molecular sieve Y10 obtained by the test are shown in the following Table 1.

PREPARATION EXAMPLE 11

According to the method in preparation example 1, except that the HY type molecular sieve in (1) was replaced with HX type molecular sieve (molar ratio of silica/alumina was 2,w (Na ₂ O) =0.0156%). The number of the prepared metal modified molecular sieve is Y11.

The physicochemical properties of the molecular sieve Y11 obtained by the test are shown in the following Table 1.

Preparation example 12

(1) 50g of HY molecular sieve (molar ratio of silica/alumina 6,w (Na ₂ O) =0.0628%), the first ion exchange is performed on the HY molecular sieve by using a lanthanum nitrate solution, the concentration of lanthanum nitrate is 300g/L, the exchange temperature is 80 ℃, the exchange time is 1h, and the mass ratio of the lanthanum nitrate solution to the HY molecular sieve is 3:1, filtering and drying the exchanged molecular sieve, and then performing first roasting at 550 ℃ for 1h under the pressure of 0.02MPa, and introducing 0.1M ammonia water at the concentration of 0.1mL/min in the roasting process to obtain a first exchanged molecular sieve;

(2) Performing a second ion exchange on the first exchange molecular sieve, the second ion exchange temperature being 90 ℃ different from the first ion exchange; and roasting to obtain the second exchange molecular sieve.

(3) And roasting the second exchange molecular sieve in the atmosphere of air in a muffle furnace at 600 ℃ for 4 hours to obtain the finished molecular sieve, wherein the number of the finished molecular sieve is Y12.

The physicochemical properties of the molecular sieve Y12 obtained by the test are shown in the following Table 1.

Comparative preparation example 1

The untreated HY molecular sieve of preparation 1 was used and was numbered DY1. The physicochemical properties of the molecular sieve DY1 obtained by the test are shown in the following Table 1.

Comparative preparation example 2

(1) 50g of HY molecular sieve (molar ratio of silica/alumina 6,w (Na ₂ O) =0.0628%), first ion exchange is performed on the HY molecular sieve by using a lanthanum nitrate solution, the concentration of lanthanum nitrate is 150g/L, the exchange temperature is 80 ℃, the exchange time is 1h, and the mass ratio of the solution to the molecular sieve is 3:1, filtering and drying the exchanged molecular sieve, roasting at 550 ℃ for 1h under the pressure of 0.02MPa, and simultaneously introducing 0.1M ammonia water at the concentration of 0.1mL/min in the roasting process; and roasting to obtain a first exchange molecular sieve, and detecting and calculating by XRF to obtain the lanthanum metal with the mass fraction of 5.83%.

(2) And (3) carrying out second ion exchange and second roasting on the first exchange molecular sieve to obtain a second exchange molecular sieve, wherein the conditions are the same as those of the step (1), and the second exchange molecular sieve is subjected to XRF detection and calculation to obtain the lanthanum metal with the mass fraction of 6.97%.

(3) And roasting the second exchange molecular sieve in the muffle furnace at 600 ℃ for 4 hours in the air atmosphere to obtain the finished molecular sieve with the number DY2.

The physicochemical properties of the molecular sieve DY2 obtained by the test are shown in the following Table 1.

Comparative preparation example 3

(1) 50g of HY molecular sieve (molar ratio of silica/alumina 6,w (Na ₂ O) =0.0628%), the first ion exchange is performed on the HY molecular sieve by using lanthanum nitrate solution, the concentration is 900g/L, the exchange temperature is 80 ℃, the exchange time is 1h, and the mass ratio of the solution to the molecular sieve is 3:1, evaporating the molecular sieve after exchange to remove water, drying, roasting at 550 ℃ for 1h under the pressure of 0.02MPa, and simultaneously introducing 0.1M ammonia water at the concentration of 0.1mL/min in the roasting process; and after roasting, the molecular sieve is detected by XRF and calculated to obtain the lanthanum metal with the mass fraction of 19.06%.

(2) And (3) carrying out second ion exchange and second roasting on the first exchange molecular sieve to obtain a second exchange molecular sieve, wherein the method is the same as that of the step (1), and the second exchange molecular sieve is subjected to XRF detection and calculation to obtain the lanthanum metal with the mass fraction of 31.80%.

(3) And roasting the second exchange molecular sieve in the muffle furnace at 600 ℃ for 4 hours in the air atmosphere to obtain the finished molecular sieve with the number DY3.

The physicochemical properties of the molecular sieve DY3 obtained by the test are shown in the following Table 1.

Comparative preparation example 4

According to the method of preparation example 1, except that the same amount of water was introduced in place of ammonia water during both the first calcination and the second calcination, the obtained molecular sieve was designated as DY4, and the physicochemical properties of the molecular sieve DY4 obtained by the test were as shown in the following table 1.

TABLE 1

Table 1, below

The following examples are presented to illustrate the preparation of solid acid catalysts in the present invention.

Example 1

Molecular sieve sample Y1 and pseudo-boehmite (average particle size 100 μm) were taken at a dry basis weight percent of 80:20, respectively adding 3wt% of sesbania powder and 3wt% of nitric acid (based on the total weight of the dry basis of the molecular sieve and the pseudo-boehmite), and mixing according to the mass ratio of 1 based on the dry basis of the molecular sieve and the pseudo-boehmite: 1 adding deionized water, uniformly mixing, extruding and molding, drying at 110 ℃ for 6 hours so that the dry basis weight of the dried mixed molded product is 65wt%, and then roasting at 550 ℃ for 4 hours in air to obtain the solid acid catalyst G1.

Catalyst evaluation:

alkylation of benzene with 1-dodecene at 120deg.C under 3MPa with a hydrocarbon feed space velocity of 0.354h ^-1 The feed benzene alkene material was in a mass ratio of 60:1. the results of the conversion of 1-dodecene and the selectivity to monoalkylbenzene are shown in Table 2.

Conversion (%) = (amount of substance of 1-dodecene before reaction-amount of substance of 1-dodecene after reaction)/amount of substance of 1-dodecene before reaction×100%;

monoalkylbenzene selectivity (%) = amount of monoalkylbenzene material after reaction/amount of material of total reaction product x 100%;

linear degree (%) =amount of substance of linear alkylbenzene after reaction/amount of substance of monoalkylbenzene after reaction×100%;

the results of the steady operation evaluation are shown in FIG. 2, and it is clear from FIG. 2 that the monoalkylbenzene selectivity was always close to 100% and the alkylbenzene linearity was always 94% or more in the steady operation evaluation of 260 hours.

Examples 2 to 12

The procedure of example 1 was followed except that Y1 was replaced with the metal-modified molecular sieve of preparation examples 2 to 12, respectively, to obtain solid acid catalysts G2 to G12.

Alkylation reactions were carried out using the above-mentioned solid acid catalysts G2 to G12, respectively, according to the evaluation method in example 1, and the results are shown in Table 2 and the following Table 2.

Example 13

The catalyst preparation procedure in example 1 was replaced with: molecular sieve sample Y1 was taken with silica (average particle size 0.05 μm) at a dry weight percent of 80:20, respectively adding 3wt% of sesbania powder and 3wt% of nitric acid (based on the total weight of dry basis of molecular sieve and silicon dioxide), wherein the mass ratio of the sesbania powder to the nitric acid is 0.5 based on the dry basis of the molecular sieve and the silicon dioxide: 1 adding deionized water, uniformly mixing, extruding and molding, drying at 150 ℃ for 6 hours so that the dry basis weight of the dried mixed molded product is 70wt%, and then roasting at 600 ℃ for 6 hours in air to obtain the solid acid catalyst G13.

Alkylation was carried out using the above-mentioned solid acid catalyst G13 according to the evaluation method in example 1, and the results are shown in Table 2.

Example 14

The procedure of example 1 was followed except that molecular sieve sample Y1 was replaced with pseudo-boehmite at 60 weight percent on a dry basis: 40 to give solid acid catalyst G14.

Alkylation was carried out using the above-mentioned solid acid catalyst G14 according to the evaluation method in example 1, and the results are shown in Table 2 below.

Comparative examples 1 to 4

The procedure of example 1 was followed, except that Y1 was replaced with each of the molecular sieves DY1-DY4 obtained in comparative preparation examples 1-4, respectively, to obtain solid acid catalysts DG1-DG4.

The alkylation reactions were carried out using the solid acid catalysts DG1 to DG4, respectively, according to the evaluation method in example 1, and the results are shown in Table 2 below.

TABLE 2

Continuous table 2

As can be seen from the results in Table 2 and subsequent Table 2, the solid acid catalyst prepared in the examples of the present invention has high catalytic activity, and the conversion rate of the reactants is high in the alkylation reaction of 1-dodecene and benzene, wherein the selectivity of monoalkylbenzene is more than 98%, and the linear degree of alkylbenzene is more than 94%. The stability of the monoalkylbenzene selectivity and the alkylbenzene and the linearity is good in the stable operation evaluation for 260 hours, and the method can be suitable for large-scale industrial application.

The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, a number of simple variants of the technical solution of the invention are possible, including combinations of the individual technical features in any other suitable way, which simple variants and combinations should likewise be regarded as being disclosed by the invention, all falling within the scope of protection of the invention.

Claims

1. A solid acid catalyst, characterized in that the catalyst comprises a metal modified molecular sieve and a refractory inorganic oxide;

2. The solid acid catalyst of claim 1, wherein the mass ratio of the metal modified molecular sieve to the refractory inorganic oxide on a dry matrix basis is 99:1-20:80, preferably 95:5-25:75, more preferably 90:10-50:50.

3. the solid acid catalyst according to claim 1 or 2, wherein the refractory inorganic oxide is selected from at least one of alumina, zirconia, silica, and titania;

preferably, the refractory inorganic oxide has a particle size of 0.005 to 200. Mu.m, more preferably 0.01 to 100. Mu.m.

4. A solid acid catalyst according to any one of claims 1 to 3, wherein the ratio of the mass fraction of the surface phase metal as measured by XPS to the mass fraction of the bulk metal as measured by XRF test in the metal modified molecular sieve, in terms of mass fraction of the element, is not more than 1.35, preferably 0.9 to 1.35;

preferably, the metal is contained in an amount of 12 to 23wt% in terms of elements based on the total amount of the metal-modified molecular sieve;

Preferably, the metal has an atomic radius of 120-270pm, preferably 160-240pm;

preferably, the metal is selected from at least one of alkaline earth metals, group IIIB metals, and group IIIA metals; further preferably at least one of La, ce, sr and Y.

5. The solid acid catalyst of any one of claims 1-4, wherein the metal modified molecular sieve is a silica-alumina molecular sieve;

preferably, the molar ratio of silica/alumina in the metal modified molecular sieve is 1-100:1, preferably 3-20:1, a step of;

preferably, the metal modified molecular sieve is selected from at least one of an X-type molecular sieve, a Y-type molecular sieve, an MCM-22 type molecular sieve, a Beta-type molecular sieve and a MOR-type molecular sieve, preferably an X-type molecular sieve and/or a Y-type molecular sieve.

6. A method for preparing a solid acid catalyst, comprising: mixing, forming and roasting a metal modified molecular sieve, a heat-resistant inorganic oxide and/or a precursor thereof, water, and optionally an extrusion aid and a peptizing agent to obtain the solid acid catalyst;

7. The process of claim 6, wherein the metal modified molecular sieve is prepared by a process comprising:

8. The process of claim 7, wherein the molecular sieve precursor is a hydrogen or sodium form of molecular sieve;

Preferably, the molecular sieve precursor is a silica-alumina molecular sieve, and the molar ratio of silica/alumina in the molecular sieve is preferably 1 to 100:1, preferably 3-20:1, a step of;

preferably, the molecular sieve precursor is selected from at least one of an X-type molecular sieve, a Y-type molecular sieve, an MCM-22-type molecular sieve, a Beta-type molecular sieve, and a MOR-type molecular sieve, preferably an X-type molecular sieve and/or a Y-type molecular sieve;

preferably, the molecular sieve precursor is sodium molecular sieve, and the first exchange liquid and/or the second exchange liquid further comprise ammonium salt;

preferably, the ammonium salt is selected from at least one of ammonium nitrate, ammonium chloride and ammonium sulfate;

preferably, the concentration of ammonium salt in the first exchange liquid and/or the second exchange liquid is 50-200g/L independently.

9. The production method according to claim 7 or 8, wherein the soluble compound of a metal is selected from at least one of a chloride, a nitrate, a phosphate, and a sulfate of a metal;

preferably, the first exchange liquid and the second exchange liquid each independently comprise a solvent, and the solvent is preferably water;

preferably, the concentration of the soluble compounds of the metals in the first exchange liquid and/or the second exchange liquid is 100-500g/L independently;

Preferably, the metal has an atomic radius of 120-270pm, preferably 160-240pm;

preferably, the metal is selected from at least one of alkaline earth metals, group IIIB metals, and group IIIA metals; further preferably at least one of La, ce, sr and Y;

preferably, the mass ratio of the first exchange liquid to the molecular sieve precursor is 2-8:1, a step of;

preferably, the mass ratio of the second exchange liquid to the first exchange molecular sieve is 3-6:1, a step of;

preferably, the conditions of the first ion exchange include: the exchange temperature is 50-90 ℃, preferably 70-90 ℃; the exchange time is 0.5-2h, preferably 0.5-1.5h;

preferably, the exchange temperature of the second ion exchange is 0-15 ℃, preferably 1-10 ℃, higher than the exchange temperature of the first ion exchange;

preferably, the metal is contained in an amount of 12 to 23% by weight on an elemental basis based on the total amount of the metal-modified molecular sieve.

10. The production method according to any one of claims 7 to 9, wherein the alkaline atmosphere is provided by an aqueous solution of an alkaline compound;

preferably, the basic compound is selected from at least one of ammonia, ammonium carbonate and urea;

preferably, the concentration of the alkaline compound in the aqueous solution of the alkaline compound is 0.01-2mol/L;

Preferably, the basic atmosphere is introduced at a rate of 0.01 to 0.5mL/min relative to 50g of molecular sieve precursor;

preferably, the conditions of the first firing include: the roasting temperature is 400-600 ℃, the roasting time is 0.5-3h, the pressure is 0.01-0.1MPa, and the pressure is gauge pressure;

11. The production method according to any one of claims 7 to 10, wherein the oxygen-containing atmosphere is air or a mixture of oxygen and an inert gas;

preferably, the oxygen content in the oxygen-containing atmosphere is 16 to 30vol%, preferably 18 to 25vol%;

preferably, the temperature of the high temperature treatment is 50-100 ℃ higher than the second firing temperature;

preferably, the conditions of the high temperature treatment include: the temperature is 500-700 ℃, preferably 550-650 ℃, and the treatment time is 2-12h, preferably 4-8h.

12. The production method according to any one of claims 6 to 11, wherein the mass ratio of the metal-modified molecular sieve and the heat-resistant inorganic oxide and/or the precursor thereof on a dry matrix basis is 99:1-20:80, preferably 95:5-25:75, more preferably 90:10-50:50.

13. The production method according to any one of claims 6 to 12, wherein the heat-resistant inorganic oxide is at least one selected from the group consisting of alumina, zirconia, silica and titania;

preferably, the particle size of the refractory inorganic oxide and/or precursor thereof is 0.005 to 200 μm, more preferably 0.01 to 100 μm;

preferably, the extrusion aid is selected from at least one of sesbania powder, cellulose and starch;

preferably, the extrusion aid is used in an amount of 0-20wt% of the total weight of the metal modified molecular sieve and the heat-resistant inorganic oxide and/or the precursor thereof, and further preferably, the extrusion aid is used in an amount of 1-5wt% of the total weight of the metal modified molecular sieve and the heat-resistant inorganic oxide and/or the precursor thereof;

preferably, the peptizing agent is selected from at least one of citric acid, nitric acid and phosphoric acid;

preferably, the amount of the peptizing agent is 0 to 20wt% of the total weight of the dry basis of the metal modified molecular sieve and the heat-resistant inorganic oxide and/or the precursor thereof, and further preferably, the amount of the peptizing agent is 1 to 8wt% of the total weight of the dry basis of the metal modified molecular sieve and the heat-resistant inorganic oxide and/or the precursor thereof;

Preferably, the ratio of the amount of water to the total weight of the metal modified molecular sieve and the dry basis of the refractory inorganic oxide and/or precursor thereof is from 0.2 to 1.2:1, further preferably, the ratio of the amount of water to the total weight of the metal modified molecular sieve and the dry basis of the refractory inorganic oxide and/or precursor thereof is from 0.3 to 1:1, a step of;

preferably, the roasting temperature is 400-650 ℃, and the roasting time is 1-12h.

14. A solid acid catalyst produced by the production process according to any one of claims 6 to 13.

15. Use of the solid acid catalyst of any one of claims 1-5 and 14 for the preparation of long chain alkylbenzenes.