RU2460715C2 - Method of producing monoalkylated aromatic compounds with high linearity and controlled isomery - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing a linear monoalkylaromatic compound with controlled concentration of 2-phenyl isomers and very low colour index after sulphonation, involving use of a catalyst system based on highly stable solid catalysts. The alkylation process is carried out with a catalyst which enables to obtain a linear alkylaromatic compound with minimum content of 2-phenyl isomers, which constitutes 20 wt %, contains MOR type zeolite, from 0.01 to 0.20 wt % of at least one metal selected from a group consisting of Li, Na, K, Mg or Ca, with maximum Na content of 0.01%, and from 0 to 0.5 wt % of at least one metal selected from a group consisting of Ti, Zr and Hf, wherein the catalyst, which enables to obtain at most 20 wt % 2-phenyl isomers, also contains FAU type zeolite, from 0.5 to 2 wt % of at least one metal selected from a group consisting of Li, Na, K, Mg or Ca, and rare-earth metals in amount of: from 4.5 to 10 wt % La, from 1.2 to 4 wt % Ce, from 0.5 to 1.5 wt % Pr and from 2 to 3 wt % Nd.

EFFECT: high activity and high selectivity with respect to linear monoalkylated compounds.

19 cl, 8 ex, 28 tbl, 3 dwg

Description

FIELD OF TECHNOLOGY

The present invention generally relates to catalytic alkylation reactions of aromatic compounds and, in particular, to zeolite type catalysts used in these reactions.

BACKGROUND

Alkylaromatic compounds are an important family of substances that are used as raw materials in many industries, such as the production of plasticizers, polymeric materials, insecticides, in agriculture to prevent the adhesion of fertilizers, in the production of textiles and fibers, in the leather and furrier industries, in the production of herbicides, in industrial cleaning methods, in the photographic industry, in the production of adhesive materials and extinguishing agents products such as wetting agents in electrochemical processes to remove contaminants and lubricants from the surface of the substrate, and in biodegradable detergents, in which case they are linear monoalkyl aromatic compounds (Surfactants in Consumers Products, Theory, Technology and Application, Edited by J .Falbe, Springer Verlag, 1987).

The standard method used in the petrochemical industry to produce linear monoalkyl aromatic compounds, especially for detergent applications, is to dehydrogenate linear paraffins to obtain linear monoolefins and then perform alkylation of benzene with these monoolefins so as to form a linear chain of the monoalkylated product (linear monoalkyl aromatic compound), also called linear alkylbenzene (LAB). Linear alkyl sulfonate (LAS) is a product that is used in the final detergent compositions. LAS is obtained by sulfonation of LAB and subsequent neutralization of the corresponding sulfonic acids (H-LAS) with aqueous solutions of alkaline or alkaline earth hydroxides according to standard methods of the prior art. The linear olefins used in the process have nine to sixteen carbon atoms. The alkylation step is carried out in the liquid phase in the presence of Friedel-Crafts type catalysts, for example hydrofluoric acid. The hydrogen fluoride method is well known and is used in industry (with its help, approximately 75% of 3.3 million metric tons of LAB obtained per year is obtained), obtaining a high yield (> 92 wt.%) Of LAB with a relatively low selectivity for 2 -phenylisomers of less than 20%. A combined method for producing LAB is described in Handbook of Petroleum Refining Process, published by Robert A. Meyers, 1986, pp. 1-23, incorporated by reference. US Pat. No. 5,276,231 describes the intermediate steps of a method for producing LAB, such as the selective hydrogenation of diolefin by-products from the dehydrogenation of paraffins, and the separation of non-linear by-products from the stream of the dehydrogenation step. However, the use of HF has some drawbacks at the operational level, since it requires very careful handling and equipment made of special materials, because of its high corrosion ability, which leads to high fixed and current costs; therefore, attempts are being made to develop alternative catalysts based on solids with an acidic nature. Currently, the only industrial-grade method that uses heterogeneous catalysis is the DETAL® method (based on the patents PI 9204326-7, ES 2007545 and US 5146026), with which approximately 15% of the global LAB production is obtained. It is characterized by the use of amorphous fluorinated aluminosilicates as a heterogeneous catalyst and in this way approximately 30% by weight of 2-phenyl isomers are obtained.

The alkylation reaction can be characterized by the following indicators: conversion, selectivity for monoalkylbenzene and isomer distribution.

1) Alkylation conversion or, more specifically, relative conversion:

In the alkylation reaction contemplated by this invention, aromatics are always used in stoichiometric excess with respect to olefins. Relative conversion can be defined as the proportion of the limiting reagent, in this case olefin, which is consumed to produce all products, thus:

where N _A0 represents the number of moles of olefin at the inlet to the reactor and N _A represents the number of moles of the same reagent at the outlet of the reactor.

2) Selectivity with respect to monoalkyl aromatic compounds:

It is defined as

where W _mab is the mass of monoalkylated aromatic compound (monoalkyl aromatic compound) to be obtained, W _lightly is the mass of all by-products lighter than the lightest monoalkyl aromatic compound of interest, and W _strand is the total mass of substances whose molecular weight higher than the molecular weight of the resulting monoalkyl aromatic compounds.

The heavy alkylate group includes all chemicals with a molecular weight higher than that of the monoalkyl aromatic compound. It usually consists of polyalkyl aromatic compounds (mainly dialkyl aromatic compounds), diphenyl alkanes, oligomerized olefins and alkylates of these oligomerized olefins formed during the alkylation step. These products are mainly formed during the alkylation reaction. Dialkyl aromatic compounds are formed by alkylation with an olefin of a previously formed monoalkyl aromatic compound. Diphenylalkanes are formed by the alkylation of benzene with a diolefin, which is dehydrocyclic. The formation of heavy by-products of this variety in the method for producing a monoalkyl aromatic compound is undesirable, since these by-products do not have any washing action (cleaning ability) in the washing process due to their strong lipophilic nature. When they are formed, they reduce the economic efficiency of the method for producing monoalkyl aromatic compounds, since they do not allow the integral use of raw materials. In addition, they must be separated from the monoalkyl aromatic compound so that they do not affect the surface-active strength of the final LAS, and they are marketed as emulsifiers that lower the cost of the goods. In addition, among the heavy alkylates, there are other compounds that need to be taken into account, such as alkyl polyaromatic compounds formed by alkylation of mono-olefins of polyaromatic compounds obtained in the dehydrogenation step. Even at the trace level, these by-products sharply reduce the quality of the final LAS, as they significantly increase its color after sulfonation. Moreover, they cannot be separated from the target product, since they appear at the level of traces and they are eluted together with the heaviest monoalkylated LAB due to overlapping ranges of their distillation temperatures.

3) Isomer distribution:

Among the obtained monoalkyl aromatic compounds, the distribution of isomers can be defined as the mass percentage of each type of obtained isomers, such as 2-phenyl, 3-phenyl ... 6-phenyl isomers, as well as branched alkylate.

The distribution of isomers plays a very important role in the solubility and stability of the final detergents, especially liquid formulations, as well as in their surface activity and in the rate of their biological decomposition.

2-phenyl isomers are those alkyl molecules that have an aromatic ring linked to an alkyl chain at position 2 of the alkyl chain. The content of 2-phenyl isomers is defined as the mass percentage of 2-phenyl isomers in a mixture of LAB or LAS and is calculated by the following formula:

2-phenyl isomer [%] = (mass of 2-phenyl isomer) * 100 / (total mass of LAB or LAS)

Currently, technologies introduced at the industrial level (HF and DETAL®) make it possible to obtain LAB with only an average content of 2-phenylisomers of 18 and 30%, respectively. With regard to solubility and stability, the ideal concentration range of 2-phenylisomers is from 25 to 30% by weight. However, LAB mixtures with an external isomer content (2 + 3 phenyl) of more than 60 wt.% Are characterized by the fact that they provide LAS with a greatly increased surface activity after sulfonation and neutralization. However, these LAS have a significant disadvantage due to their low solubility in cold water and high viscosity. LAS mixtures, including more than 60 wt.% Of external isomers (2 + 3 phenyl), tend to form highly insoluble gels (low cloud point during cooling) with high viscosity, which complicates their use and processing. For this reason, it would be desirable to include a hydrotrop to improve the solubility of the final surfactant when the content of 2-phenylisomers exceeds 60 wt.%. Although there are many patents related to the use of hydrotropes, one of them is considered as the most recommended for this method. PCT / ES2005000169 relates to a process for preparing a suitable hydrotrope from pre-dehydrogenated paraffins, especially from such by-products isolated during the purification step of the monoolefin.

Finally, branched alkyl aromatic compounds (branched alkylates) can be defined as those alkyl aromatic compounds in which the alkyl chain attached to the aromatic ring is not a linear or normal, but a branched alkyl group. These non-normal alkyl groups contain radicals such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl and various hexyl, heptyl, octyl variants attached anywhere in the alkyl chain except at the ends of the chain. Branched alkylates are formed by alkylation with branched olefins derived from those branched paraffins that are present in fresh starting paraffins, or by alkyl rearrangement processes that occur during the dehydrogenation and alkylation steps.

Among the branched alkylates, there are alkylates that have one of the carbon atoms of an aliphatic alkyl group in the position of the quaternary carbon. A quaternary carbon atom in an alkyl chain is defined as carbon bonded to four other carbon atoms, and one of them can be bonded to a carbon atom in the phenyl group to form a quaternary alkyl phenylalkane. If the quaternary carbon is the second carbon atom in the alkyl chain, the quaternary carbon present in the resulting 2-alkyl-2-phenylalkane may be called the “terminal quaternary carbon”. It is known that, like single-branched alkylates, these substances have a biodegradation rate similar to linear alkylbenzenesulfonate. However, when the quaternary carbon is another carbon atom in the alkyl chain, for example 5-methyl, 5-phenylalkane, it is called “internal quaternary carbon” and the corresponding alkylbenzenesulfonate has a much lower biodegradation rate. In the articles "Iso-branching of LAS biodegradation study of two model compounds", L. Cavalli, G. Cassani, M. Lazzarin, C. Maraschin, G. Nuzzi, JL Berna, J. Bravo, J. Ferrer, A. Masno , Toxicology & Environmental Chemistry, vol. 54, pp. 167-186, 1966 and Biodegradation of co-products of commercial LAS, AMNielsen, LN Britton, L. Cavalli, JL Berna, The Cler Review, vol. 2, No. 1, pp. 14-27, 1996 provides scientific evidence of the biological degradation behavior of these branched alkylbenzene derivatives.

International patent application WO 2007/104805, considered as the closest analogue for this invention, relates to a method for producing linear alkylbenzenesulfonates with controlled content of 2-phenylisomers and very low color after sulfonation, which uses a catalytic system based on solid highly stable catalysts with high selectivity in relation to monoalkylate compounds. However, through the method described in this patent, a branched alkylbenzene content (more than 4 wt.%, Although up to 10 wt.% Can be achieved under certain operating conditions) is significantly higher than that obtained as in the standard industrial method based on a homogeneous catalysis with HF (about 3.5 wt.%), as well as in the industrial method based on heterogeneous catalysis (DETAL® method, in which about 3 wt.% of these branched products are obtained). Since it was shown that the LAS obtained from both of these industrial processes is rapidly and completely biodegradable at these branched alkylate contents (Berna JL et al. Tenside Surfactants Detergents, 26, 2, 1989), it would be advisable that new alkylation methods based on a heterogeneous catalyst, provided the possibility of obtaining linear monoalkylaromatic compounds with preferably lower or at least the same amount of these branched by-products in comparison with the amount obtained in and currently used technologies. Thus, optimal environmental behavior of the sulfonated and neutralized final product (LAS) is ensured.

Moreover, although the catalysts provided for in international patent application WO 2007/104805 are able to increase the duration of the reaction cycles compared to the heterogeneous catalysts currently used in the DETAL method (60 hours versus 24 hours with modern heterogeneous technology), on an industrial level it is important to be able to extend this duration even more. In this way, the frequency and number of catalyst washing cycles can be reduced. This is reflected in lower operating costs for auxiliary equipment (longer net operating time of the reactor and lower costs at the stage of catalyst regeneration), as well as lower energy consumption (pumping and heating of the regenerating agent) and atmospheric emissions associated with this process.

Finally, although the catalysts provided for in international patent application WO 2007/104805 are able to reduce the formation of heavy by-products compared to existing technology, it would be advantageous to be able to reduce their formation even further in order to maximize the cost-effectiveness of the production of LAB (integral utilization of raw materials). materials), as well as improving the quality of the product by reducing its color after sulfonation.

DESCRIPTION OF THE INVENTION

The present invention provides a method for producing monoalkyl aromatic compounds with high linearity (they will be called linear monoalkyl aromatic compounds, although they may contain minimal amounts of branched alkylates), a minimum content of heavy alkylates and a minimum color, at the same time also having an adjustable content of 2-phenyl isomers, in which uses a new catalyst that provides a low content of 2-phenyl, which can be more selective, active and stable than catalysts provided in the prior art. Due to the greater selectivity with respect to monoalkyl aromatic compounds with this new catalyst, it is possible to obtain a final product with a lower content of heavy alkylates than that provided in the prior art, which increases the economic efficiency of the method by increasing the utilization of raw materials and at the same time improves it quality due to a decrease in color after sulfonation of the resulting LAS. This color is further minimized by suitable purification of both the raw materials and the resulting linear monoalkyl aromatic compound. In addition, a linear monoalkyl aromatic compound is obtained with a branched alkylate content equal to this value for the technologies used in this field, which provides rapid complete biological decomposition of the resulting LAS. The catalyst is more resistant to deactivation than the catalysts provided in the prior art, which provides a greater number of reaction cycles and a lower frequency of washing cycles, while maintaining high activity, which leads to lower operating costs.

This method includes a method of utilizing the impurities of the intermediate streams so as to obtain a hydrotrop which, appropriately added when the content of 2-phenylisomers in the monoalkyl aromatic compound exceeds 60 wt.%, Makes it possible to obtain a product with higher solubility than with the addition of other hydrotropes, usually used in the prior art. In addition, since the new catalyst is more resistant to deactivation during contamination, the duration of the reaction cycles increases significantly and the frequency of the washing cycles decreases. This leads to longer production cycles and a decrease in the level of energy consumption associated with the regenerative washing step (pumping the washing agent and heating).

Therefore, the first aspect of the invention relates to a method for producing a linear monoalkyl aromatic compound with a content of 2-phenylisomers from 18 to 70 wt.% By catalytic alkylation of an aromatic compound with a purified alkylating agent, comprising the following steps:

1) catalytic dehydrogenation of a linear paraffin feed stream to produce linear monoolefins, unreformed paraffins and a certain amount of by-products, such as diolefins and non-linear compounds;

2) treating the effluent of step (1) to selectively hydrogenate the diolefins obtained as by-products in step (1) to monoolefins, thereby obtaining a starting alkylating agent including linear monoolefins, unreformed paraffins and non-linear compounds;

3) purification of the starting alkylating agent by separating non-linear products contained in the effluent of step (2) so that the resulting purified alkylating agent contains monoolefins and paraffins;

4) processing non-linear products separated in stage (3), with the formation of a hydrotropic precursor,

5) alkylation of an aromatic hydrocarbon with monoolefins present in a purified alkylating agent, by combining two alkylation processes based on:

a) an alkylation process with a catalyst that provides a linear alkyl aromatic compound with a maximum content of 2-phenylisomers of 20 wt.%,

b) an alkylation process with a catalyst that provides a linear alkyl aromatic compound with a minimum content of 2-phenylisomers of 20 wt.%, which includes a MOR type zeolite, from 0.01 wt.% to 0.20 wt.% of at least one from metals selected from the group consisting of Li, Na, K, Mg or Ca, with a maximum Na content of 0.01%, and from 0 to 0.5 wt.% of at least one of the metals selected from the group consisting of from Ti, Zr, Hf;

6) fractionation of the effluent of stage (5) to separate unreacted aromatic compounds, paraffins and the most severe by-products from the target linear monoalkyl aromatic compounds,

7) purification of the fraction of the target linear monoalkyl aromatic compounds coming from stage (6).

This method is characterized in that the catalyst, which provides the possibility of obtaining a maximum of 20 wt.% 2-phenylisomers, includes a zeolite type FAU, from 0.5 to 2 wt.% At least one of the metals selected from the group consisting of Li, Na, K, Mg or Ca, and from 8 to 16.5 wt.% At least one rare earth metal selected from the group consisting of La, Ce, Pr, Nd, Pm, Sm or Eu.

In the present invention, when it comes to zeolites of the FAU or EMT-FAU type, they mean a group of zeolites with isotypic structures corresponding to the FAU structural type, such as zeolite Y, zeolite Na-X, siliceous Na-Y, zeolite Linde X, zeolite Linde Y, zeolite ZSM-3 and zeolite ZSM-20, preferably zeolite Linde or zeolite Y.

In the present invention, when it comes to zeolites of the MOR type, they mean a group of zeolites with isotypic structures corresponding to the structural type of MOR, such as mordenite, zeolite Na-D and zeolite Ca-Q, most preferably mordenite,

In a specific embodiment of the present invention, the catalyst, which provides a maximum of 20% 2-phenylisomers, comprises 0.9 wt.% Na.

In another specific embodiment of the present invention, the catalyst, which provides a maximum of 20% of 2-phenylisomers, comprises from 4.5 to 10 wt.% La, from 1.2 to 4 wt.% Ce, from 0.5 to 1.5 wt. .% Pr and from 2 to 3 wt.% Nd.

In another specific embodiment of the present invention, a catalyst that provides a maximum of 20% of 2-phenylisomers includes:

a) an X-ray powder diffraction pattern, characterized in that the most intense diffraction peak appears at an angle of 2 theta corresponding to 6.2 °, and other main peaks appear at angles of diffraction of 2 theta corresponding to 23.6 °; 20.3 °; 21.6 °; 27.0 °; 31.3 °, arranged in decreasing order of intensity of the corresponding peaks;

b) the total silicon / aluminum molar ratio is from 0.5: 1.0 to 3.0: 1.0, preferably from 0.5: 1.0 to 2.0: 1.0;

c) the molar ratio of silicon / aluminum in the structural lattice from 1.5: 1.0 to 2.5: 1.0, preferably from 2.1: 1.0 to 2.3: 1.0;

g) a total specific surface area (BET) of 500 to 1000 m ² / g, preferably 600 to 700 m ² / g;

d) an area of micropores comprising from 500 to 900 m ² / g, preferably from 500 to 600 m ² / g,

e) a specific micropore volume of from 0.1 to 0.3 ml / g, preferably from 0.19 to 0.22 ml / g,

g) the distribution of macropores, in which the diameter of the macropores is from 20 to 2000 angstroms, preferably 40 angstroms.

In a specific embodiment of the present invention, in step (1), paraffins include straight chain alkanes containing from 8 to 30 carbon atoms, preferably from 10 to 16 carbon atoms, more preferably they contain from 10 to 14 carbon atoms. These paraffins can be dehydrogenated and purified by any method described in the prior art.

In a specific embodiment of the present invention, the aromatic hydrocarbon is selected from the group consisting of toluene, xylene, benzene or mixtures thereof, but preferably it is benzene.

In a specific embodiment of the present invention, the aromatic hydrocarbon and olefins are mixed before the alkylation reaction of step (5) in a molar ratio of aromatic hydrocarbon: olefin of 5: 1 to 70: 1, preferably 10: 1 to 30: 1, and more preferably 10: 1 to 15: 1.

In a specific embodiment of the present invention, the mixture of aromatic hydrocarbon and purified alkylating agent comprises a maximum of 0.3 wt.% Non-linear compounds.

In a specific embodiment of the present invention, the mixture of aromatic hydrocarbon and purified alkylating agent also includes from 0 to 0.1 wt.% Water.

In a specific embodiment of the present invention, in the step (5), the alkylation reactions are carried out simultaneously.

In a specific embodiment of the present invention, in step (5), the alkylation reaction is carried out in a reactor with a catalyst arrangement selected from the group consisting of a fixed bed with one catalyst, a fixed bed with two completely mixed different catalysts, at least two different fixed beds with one and the same catalyst in each bed of at least two different fixed beds with different catalysts in each bed, a fluidized bed with one or more different catalysts , A slurry reactor with one or more different catalysts.

In a particular embodiment of the present invention, in step (5), the alkylation reaction is carried out in a reactor configuration that includes at least one of the reactor configurations selected from the group consisting of an independent reactor, at least two parallel reactors, at least two serial reactors, and combinations of these configurations.

In a specific embodiment of the present invention, in step (3), the purification process of the starting alkylating agent is carried out by means of separation of non-linear impurities known to one skilled in the art, such as, for example, hydrogenation, fractionation and selective adsorption. In the case of selective adsorption, the adsorbent layer consists of at least one material selected from the group consisting of zeolites, silica, silica gel, macroporous magnesium silicate, activated alumina, silica-alumina, clays, molecular sieves, cellulose acetate, macroporous polystyrene gel, activated carbon and organ-selective polymer membranes.

In a specific embodiment of the present invention, the hydrotropic precursor treatment of step (4) comprises:

a) fractionation of non-linear compounds obtained in stage (2) by distillation at atmospheric pressure, and the temperature range of the distillation of the target fraction is from 195 ° C to 259 ° C;

b) the selective hydrogenation of polyaromatic substances contained in the target fraction, which was subjected to distillation in the previous stage.

In a specific embodiment of the present invention, the hydrotropic precursor obtained in step (4) includes:

- from 2 to 20 wt.% alkylaromatic compounds with one or more alkyl groups, which in total contain 4 carbon atoms,

- from 5 to 40 wt.% alkylaromatic compounds with one or more alkyl groups, which in total contain 5 carbon atoms,

- from 15 to 30 wt.% alkylaromatic compounds with one or more alkyl groups, which in total contain 6 carbon atoms,

- from 0.5 to 50 wt.% alkylaromatic compounds with one or more alkyl groups, which in total contain 7 carbon atoms,

- from 0.01 to 10 wt.% alkylaromatic compounds with one or more alkyl groups, which in total contain 8 carbon atoms,

- from 0.5 to 10 wt.% alkylaromatic compounds with one or more alkyl groups, which in total contain 9 carbon atoms,

- from 0.5 to 10 wt.% alkylaromatic compounds with one or more alkyl groups, which in total contain 10 carbon atoms.

Hydrotrop (hydrotropic agent) as such is formed by sulfonation and neutralization of the hydrotropic precursor, either separately or in admixture with a linear monoalkyl aromatic compound.

In a specific embodiment of the present invention, the purification method of step (7) is carried out by means of removing and / or separating polyaromatic and polyalkyl aromatic impurities known to one skilled in the art, such as, for example, hydrogenation, fractionation and adsorption. In a preferred embodiment, the cleaning method of step (7) is carried out by selective adsorption using a selective clay-based adsorbent, which includes:

a) a total silicon / aluminum molar ratio of from 3: 1 to 5: 1, preferably 4.1: 1.0;

b) from 1 to 4 wt.% Fe ₂ O ₃ , preferably 2.9 wt.%,

C) from 0.5 to 2 wt.% K ₂ O, preferably 1.4 wt.%,

g) from 0.2 to 2 wt.% MgO, preferably 1.2 wt.%,

d) from 0.1 to 1 wt.% TiO ₂ , preferably 0.45 wt.%,

e) from 1800 to 2500 ppm Na, preferably 2200 wt. parts per million

g) the specific surface area according to BET, comprising from 150 to 500 m ² / g, preferably 260 m ² / g,

h) a total pore volume of from 0.1 to 2.0 ml / g, preferably 0.42 ml / g,

i) the distribution of macropores, in which the diameter of the macropores is from 20 to 800 angstroms, preferably from 20 to 200 angstroms, more preferably from 20 to 100 angstroms with an average diameter based on a pore volume of 34 angstroms.

In a specific embodiment of the present invention, the hydrotropic precursor obtained in step (4) is added to the linear monoalkyl aromatic compound stream when the content of 2-phenyl isomers of the linear monoalkyl aromatic compounds is equal to or more than 60 wt.%, And added before the purification step (7).

In a specific embodiment of the present invention, the neutralization process of step (9) is carried out by means of an alkaline substance comprising one or more cations selected from the group: Na, K, NH ₄ ⁺ , Mg, Ca, Ba, or by substituted ammonium alkalis.

In a more specific embodiment of the present invention, the olefins are α-olefins and include from 9 to 30 carbon atoms.

In a specific embodiment of the present invention, the reaction temperature is from 20 to 400 ° C.

In a specific embodiment of the present invention, the space velocity is from 1 hour ^-1 to 15 hour ^-1 .

In a specific embodiment, the method described in the present invention includes an additional step (8) of sulfonation and neutralization of the compound obtained in step (7).

In a specific embodiment of the present invention, the hydrotropic precursor obtained in step (4) is sulfonated and neutralized separately and then added to the product obtained in step (8).

Another aspect of the present invention relates to a linear sulfonated and neutralized monoalkyl aromatic compound obtained by the method described in the present invention.

Another aspect of the present invention relates to a method for producing a linear monoalkyl aromatic compound with a content of 2-phenyl isomers of at least 18 wt.% By catalytic alkylation of the aromatic compound with an alkylating agent, as described previously, where stages (1), (2), (3) and ( 4) are optional.

Another aspect of the present invention relates to corresponding cleaning compositions for dishwashing compositions, cleaning agents for hard surfaces, liquid detergents, powder detergents, paste-like cleaning compositions, gels and washing bars, which include:

a) from 1 to 99 wt.% the compound obtained in stage (8),

b) from 99 to 1 wt.% of other detergent ingredients selected from the group consisting of derivatives of fatty alcohols, fatty acids, alkyl sulfates, ethanolamines, amine oxides, alkali carbonates, ethanol, isopropanol, water, pine oil, sodium chloride, sodium silicate, polymers, alkoxylates of alcohols, perborate salts, zeolites, alkali sulfates, enzymes, hydrotropes, dyes, flavors, preservatives, polishing materials, polyacrylates, essential oils, alkaline hydroxides, ether sulfonates, branched alkylbenzenesulfonates water-soluble alkyl phenol alkoxylates, fatty amines, alpha olefinsulfonates, paraffinsulfonates, betaines, chelating agents, Wanin talo ethoxylates, polyethylamines ethoxylates, ethylene oxide block copolymers, ethoxylated alcohols, methylene sulfides, methyl sulfonates, , sulfonated diphenylalkyl oxide and polyethylene glycol.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows a diagram of a method representing the present invention, in the form of a flowchart.

Figure 2 shows a diagram of a method representing the present invention, in the form of a flowchart, which includes the stages of sulfonation and neutralization.

Figure 3 shows the reaction scheme of the present invention in the form of a flow chart where the steps of catalytic dehydrogenation of paraffin, hydrogenation of a diolefin, purification of the starting alkylating agent and isolation, purification and addition of a hydrotropic precursor are omitted,

DETAILED DESCRIPTION OF THE METHOD FOR IMPLEMENTING THE EMBODIMENT

Figure 1 presents a non-limiting diagram of the implementation of the present invention.

Stream 15 is a linear paraffin feed to a dehydrogenation unit and includes a mixture of fresh linear paraffins, stream 10, with unconverted linear paraffins separated in a crude alkylate purification unit, block 350, and recycled via stream 170. In a dehydrogenation block 300, the linear paraffin feed is converted into a mixture of linear monoolefins, unreacted paraffins and various by-products, such as diolefins and non-linear compounds. In this embodiment, which uses benzene as an aromatic hydrocarbon, the crude alkylate is a mixture of monoalkylbenzenes, unreacted benzene, paraffins and light and heavy by-products, which constitutes the alkylation effluent.

An olefin purification unit, block 310, is supplied with the dehydrogenation unit effluent via stream 20, increasing the net monoolefin content by converting certain by-products obtained in the dehydrogenation unit, mainly diolefins, to monoolefins through a selective hydrogenation reaction. The resulting stream, stream 30, is processed in block 320, which contains a selective adsorbent to eliminate non-linear compounds obtained in the dehydrogenation process.

Fresh benzene is pumped into the process through stream 50 and mixed with unreacted benzene fed by recycle (stream 160), which comes from the crude alkylate purification unit, block 350. A mixture of these two streams forms a benzene feed (stream 55), which is mixed with stream ( stream 40) exiting the selective adsorption unit 320 to form a stream 60 consisting of monoolefins, benzene and paraffins, which is fed to the alkylation units. Stream 60 is divided into two identical streams (in composition, but not necessarily in feed rate), 60a and 60b, which are fed to two different alkylation reactors, blocks 330 and 340, respectively; in the alkylation reactor 330, a catalyst is used that provides an effluent stream (stream 70) with a crude alkylate in which monoalkylbenzenes have a maximum content of 2-phenylisomers of 20% by weight, while in a reactor 340 a catalyst is used that provides an exit a stream (stream 80) with a crude alkylate in which monoalkylbenzenes have a 2-phenylisomer content of at least 20 wt.%. Streams 70 and 80 are mixed to form a stream, stream 90, consisting of crude alkylate, in which monoalkylbenzenes have a variable content of 2-phenyl (in accordance with the feed rates of streams 60a and 60b), unreacted benzene, paraffins and light and heavy by-products. Stream 90 is fed to a crude alkylate purification unit, block 350, in which unreacted benzene, paraffins and by-products lighter and heavier than monoalkylbenzenes are distilled to give a relatively pure linear monoalkylbenzene (stream 100). Paraffins are recycled to the process via stream 170, while benzene is recycled through stream 160. Then, stream 100 is fed to the purification unit of the final linear monoalkylbenzene, block 360, which contains selective adsorbent, to eliminate aromatic compounds that, even in small quantities are present in relatively pure monoalkylbenzene due to the fact that the range of their distillation temperature overlaps with the range of distillation temperature of the target linear monoalkylbenzene.

Non-linear compounds recovered in block 320 are pumped into special treatment block 380 via stream 180. Block 380 includes fractionation and hydrogenation steps to isolate and purify, respectively, the fraction of non-linear impurities of interest, which is a hydrotropic precursor (stream 190). Depending on the specific needs at the output of the device at any given time (product with a content of 2-phenylisomers constituting more or less than 60 wt.%, According to the requirement at this time), stream 190 can be transported by streams 190a and 190b or it can be omitted, if the content of 2-phenylisomers of linear monoalkylbenzene stream 100 is less than 60 wt.%. Thus, streams 190a and 190b can be dispensed with when the content of 2-phenylisomers in linear alkylbenzene of stream 100 is lower than 60 wt.%. In this case, the relatively pure linear alkylbenzene streams 100-110 are individually purified (block 360) individually, with the stream exiting block 360 (stream 120) including purified linear compounds. When the content of 2-phenylisomers in linear monoalkylbenzene exceeds 60 wt.%, The method can be carried out through two alternative channels. On the one hand, the relatively pure linear monoalkylbenzene stream, stream 100, and hydrotropic precursor stream 190a can be mixed to form stream 110, which is fed to purification unit 360. The stream leaving stream 360 (stream 120-130) contains the final linear alkyl aromatic compound. Alternatively, stream 190a can be dispensed with, so that the relatively pure linear alkylbenzene that comes from block 350, stream 100-110, is cleaned separately in block 360 and, after cleaning (stream 120), it is mixed with the hydrotropic precursor supplied by stream 190b, receiving stream 130, which includes the final linear monoalkylaromatic compound.

Figure 2 presents a non-limiting implementation scheme of this invention, which includes the stages of sulfonation and neutralization.

Stream 15 is a paraffin feed to the dehydrogenation unit and includes a mixture of fresh linear paraffins, stream 10, with non-converted linear paraffins separated in the crude alkylate purification unit, block 350, and recycled via stream 170. In the dehydrogenation unit 300, the linear paraffin feed is converted to a mixture monoolefins, unreacted paraffins, and various by-products, such as diolefins and non-linear compounds. The crude alkylate is believed to be a mixture of monoalkylbenzenes, unreacted benzene, paraffins and light and heavy by-products, which constitutes the effluent of the alkylation step.

An olefin purification unit, block 310, is supplied with the dehydrogenation unit effluent via stream 20, increasing the net monoolefin content by converting certain by-products obtained in the dehydrogenation unit, mainly diolefins, to monoolefins through a selective hydrogenation reaction. The resulting stream, stream 30, is processed in block 320, which contains a selective adsorbent to eliminate non-linear compounds obtained in the dehydrogenation block.

Fresh benzene is injected into the process via stream 50 and mixed with unreacted benzene fed by recycle (stream 160), which comes from the crude alkylate purification unit, block 350. A mixture of these two streams forms a benzene feed (stream 55), which is mixed with stream ( stream 40) exiting the selective adsorption unit 320, to form a stream 60 consisting of monoolefins, benzene and paraffins, which is fed to the alkylation units. Stream 60 is divided into two identical streams (in composition, but not necessarily in feed rate) 60a and 60b, which are fed to two different alkylation reactors, blocks 330 and 340, respectively; in the alkylation reactor 330, a catalyst is used that provides an effluent stream (stream 70) with a crude alkylate in which monoalkylbenzenes have a maximum content of 2-phenylisomers of 20% by weight, while in a reactor 340 a catalyst is used that provides an exit a stream (stream 80) with a crude alkylate in which monoalkylbenzenes have a 2-phenylisomer content of at least 20 wt.%. Streams 70 and 80 are mixed to form a stream, stream 90, consisting of crude alkylate, in which monoalkylbenzenes have a variable content of 2-phenylisomers (in accordance with the feed rates of streams 60a and 60b), unreacted benzene, paraffins and light and heavy by-products. Stream 90 is fed to a crude alkylate purification unit, block 350, in which unreacted benzene, paraffins and by-products lighter and heavier than monoalkylbenzenes are fractionated to give a relatively pure linear monoalkylbenzene (stream 100). Paraffins are recycled to the process through stream 170, while benzene is recycled through stream 160. Then, stream 100 is fed to the purification step of the final linear monoalkylbenzene, block 360, which contains a selective adsorbent to eliminate aromatic compounds that, even in small amounts, are present in relatively pure monoalkylbenzene because the range of their distillation temperature overlaps with that of the target linear monoalkylbenzene.

Non-linear compounds recovered in block 320 are pumped into special treatment block 380 via stream 180. Block 380 includes fractionation and hydrogenation steps for separating and purifying, respectively, the non-linear impurity fraction of interest, which is a hydrotropic precursor (stream 190). Depending on the specific needs at the output of the device at any given time (product with a content of 2-phenylisomers constituting more or less than 60 wt.%, According to the requirement at this time), stream 190 can be transported by streams 190a and 190b or it can be omitted, if the content of 2-phenylisomers of linear monoalkylbenzene stream 100 is less than 60 wt.%. If the content of 2-phenylisomers in stream 100 exceeds 60 wt.%, The relatively pure monoalkylbenzene stream, stream 100, and hydrotropic precursor stream 190a can be mixed to form stream 110 and they can be cleaned together in block 360 and then sent through streams 120 and 130 to to block 370, where they are sulfonated / neutralized together to produce a final stream, stream 140-150. Stream 190a can also be dispensed with so that the relatively pure linear alkyl benzene that comes from block 350, stream 100-110, is cleaned separately in block 360, and after cleaning (stream 120), it is mixed with the hydrotropic precursor supplied by streams 190b and 191a obtaining stream 130, moreover, they are sulfonated and neutralized together in block 370, thereby obtaining the final stream, stream 140-150. It is also possible to dispense with streams 190a and 191a so that stream 100 of relatively pure alkylbenzene is purified (block 360), sulfonated and neutralized (block 370) separately. The effluent from block 370 (stream 140) is then mixed with stream 192 corresponding to a hydrotropic precursor, sulfonated and neutralized separately. Stream 192 is obtained by sulfonation and neutralization of the hydrotropic precursor from block 380 (via streams 190, 190b and 191b) separately in block 390. The final stream 150 is obtained when streams 140 and 192 are mixed. If the content of 2-phenylisomers in stream 100 is less than 60 wt. .%, flows 190a and 190b can be dispensed with, and linear alkylbenzene is purified separately in block 360 and transported via streams 120-130 to a sulfonation and neutralization unit (block 370), the effluent of which (stream 140-150) is the final stream of this embodiment .

Figure 3 presents another non-limiting implementation scheme of this invention, in which stages (1), (2), (3) and (4) are optional.

Stream 10 is the supply of fresh olefins to the process. Stream 20 is a fresh supply of an aromatic compound, such as benzene, to the process. Stream 20 is mixed with stream 60, which is a recycle stream of excess aromatics after separation from the alkylation products in a distillation column, block 120. By mixing streams 20 and 60, stream 30 is obtained, which is the aromatics feed. Stream 30 is mixed in mixing block 100 with stream 10 to produce a mixture of aromatics and olefins with the desired molar ratio of olefins to aromatics, stream 40. This stream is fed to an alkylation unit, block 110, consisting of two fixed-bed reactors operated in parallel, where one reactor is loaded with a catalyst that provides crude alkylate, in which alkylbenzene contains less than 20% of 2-phenyl isomers, and the other reactor is loaded with a catalyst that provides crude o alkylate, in which alkylbenzene contains more than 20% of 2-phenyl isomers. The feed stream (stream 40) is divided into two (having the same composition, but not necessarily the same feed rate) for feeding into both reactors in which the aromatic compound is alkylated with olefins. The effluents from both reactors are combined to produce an effluent from the alkylation unit, stream 50, which consists of the unreacted aromatic compound and the alkyl aromatic compound obtained during the alkylation. Stream 50 is fractionated in a distillation column, block 120, to separate the unreacted aromatic compound in its upper part, stream 60, and the alkyl aromatic compound in its lower part, stream 70. Stream 60 is recycled to the process as mentioned above, while stream 70 is sulfonated in a falling film reactor with gaseous SO ₃ , block 130. The sulfonated product, stream 80, consists of a high-purity linear alkyl sulfonic acid with a given 2-phenylisomer content. This product can then be neutralized in block 140 with alkaline salts of calcium, barium, sodium, magnesium and ammonium in the presence of a highly ionizable compound such as phenol to obtain high-purity alkyl aromatic sulfonate, both neutral and preferably superbasic, depending on the amount of base used during neutralization.

The invention is described further, for purposes of illustration only, by means of the following examples, which should not be construed as limiting the scope of the present invention.

EXAMPLES

Example 1

This example relates to a process for the preparation of a purified alkylating agent and a process for preparing a hydrotopic precursor from impurities isolated during the purification of said alkylating agent.

The method begins with a mixture of high-purity linear paraffins (usually the paraffin content should be higher than 97 wt.% According to UOP 411), the distribution of carbon atoms in paraffins should be as shown in table 1.

Table 1 The distribution of the initial linear paraffins wt.% each paraffin <C ₁₀ 0.5 C ₁₀ eleven C ₁₁ 34 C ₁₂ 32 C ₁₃ 22 C ₁₄ one

These linear paraffins were processed by a method for selective dehydrogenation to monoolefins using a conventional industrial catalyst for the selective dehydrogenation of paraffins of a group of detergents. The dehydrogenation conditions are summarized in table 2 and provide an olefin yield of 14%.

table 2 Pressure, MPa (bar) 0.13-0.15 (1.3-1.5) Temperature ° C 469-472 The molar ratio of H ₂ / hydrocarbon 3.0-5.0 HOUSING, hour ^{-1 (*)} 20-23 (*) COSJ: Hourly fluid volumetric velocity

The effluent from the dehydrogenation step may contain up to 0.1% by weight of diolefins, which are undesirable by-products of the dehydrogenation step. For this reason, the effluent from the dehydrogenation step is subjected to a purification process. During this purification process, the effluent from the dehydrogenation step is subjected to selective dehydrogenation to convert the undesired diolefins to the desired monoolefins. For this, an industrial Ni-Mo type catalyst is used. The conditions for selective dehydrogenation are summarized in table 3.

Table 3 Pressure, MPa (bar) 0.9-1.1 (9-11) Temperature ° C 190-200

The LHSV conditions (volume ratio of the liquid charge to the catalytic layer) are adjusted to obtain a conversion of diolefins to monoolefins above 99%, this conversion is checked using the method of UOP 902-89. The resulting mixture of monoolefins and paraffins constitutes a crude alkylating agent.

The stage of purification of the alkylating agent is carried out by means of an adsorbent layer in which a certain amount of a specific molecular sieve is placed. The selected molecular sieve is a type 13X zeolite widely used in methods for the selective removal of non-linear components from a mixture of olefins and paraffins. A mixture of olefins and paraffins is passed through the bed to achieve selective adsorption of non-linear components from the previous dehydrogenation step (or which are present in the supply of fresh paraffins and / or in recycled paraffins). After the layer is saturated with non-linear components, the layer is washed with short chain paraffins to desorb olefins and paraffins that can be retained in the pores, and then it is washed with benzene to desorb previously adsorbed non-linear components, which can then be converted into a hydrotropic precursor. The operating conditions of the experimental installation of the cleaning stage are summarized in table 4.

Table 4 Particle size, standard mesh. USA from 10 to 20 Adsorption temperature, ° С 135-145 Flushing temperature, ° С 123-135 Desorption temperature, ° С 135-145 Adsorption pressure, MPa (kg / cm ² ) 2.5 (25) Flushing Pressure, MPa (kg / cm ² ) 2.5 (25) Desorption pressure, MPa (kg / cm ² ) 2.5 (25) Flushing agent n-pentane Desorption agent benzene HOUSING, hour ^-1 1.5-2.5

A mixture of olefins and paraffins from selective dehydrogenation and hydrogenation, i.e. crude alkylating agent, contains about 2 wt.% non-linear components. The composition of the alkylating agent, purified by adsorption of non-linear components on zeolite 13X, is presented in table 5.

Table 5 Compound The percentage, wt.% In the mixture nc ₁₀ 14.8 nc ₁₁ 31,0 HC ₁₂ 26.1 nc ₁₃ 18.2 HC ₁₄ <0.9 C ₁₀ olefin 1.3 C ₁₁ olefin 3.2 C ₁₂ olefin 3,1 C ₁₃ olefin 2,3 C ₁₄ olefin <0.1 Aromatic compounds <0.1

Non-linear components separated during the purification phase of the alkylating agent contain the raw material necessary to obtain a hydrotropic precursor. The following is a description of a method for transforming said impurities into a hydrotropic precursor. After purification of the alkylating agent with benzene, non-linear impurities stripped from 13X zeolite undergo atmospheric fractionation. During the fractionation stage, the goal is to separate the benzene used during desorption (then benzene should be recycled to the desorption cycle with 13X zeolite) and impurities that do not have hydrotropic potential (polyaromatic substances with high molecular weight) from the fraction of substances that have hydrotropic potential. It was found that the fraction of substances with hydrotropic potential (those substances that provide a hydrotropic effect during sulfonation and neutralization) for LAS, the purpose of this invention, is a fraction that has a distillation temperature from 195 to 259 ° C. After this fraction is separated by atmospheric distillation, it undergoes a hydrogenation process to eliminate components that can form dyes upon sulfonation. The hydrogenation conditions are shown in table 6.

Table 6 Pressure, MPa (bar) 2-3 (20-30) Temperature ° C 185-195 The molar ratio of H ₂ / hydrocarbon 1-2 HOUSING, hour ^-1 4-8

Obtained at this stage of hydrogenation, the product contains a hydrotropic precursor, the composition of which is described in table 7.

Table 7 Distribution wt.% Phenyl-C ₄ 7 Phenyl-C ₅ twenty Phenyl-C ₆ 25 Phenyl-C ₇ fifteen Phenyl-C ₈ 7 Phenyl-C ₉ 7 Phenyl-C ₁₀ 7 The total content of alkylaromatic substances 88 Other compounds 12 The average molecular weight, g / mol 165 Bromine number (ASTMD 1491 method) 130

Example 2

This example relates to the advantages of using a catalyst based on zeolite Y with a high content of rare earths (such as La, Ce, Nd and Pd) and sodium compared to a catalyst based on a zeolite Y with a low content of rare earths (such as La, Ce , Nd and Pd) and sodium in a method for the alkylation of benzene with a purified mixture of detergent group olefins / paraffins. Two catalysts are specifically compared. On the one hand, a catalyst (catalyst A) based on zeolite Y with a total content of rare earth metals of 7% and a low sodium content (0.1 wt.%), And, on the other hand, a catalyst (catalyst B) based on zeolite Y with a rare earth content of more than 71% (12 wt.% Rare earth) and a sodium content of more than 90% (0.9 wt.%).

Both catalysts were tested using extruded particles of the same size. Benzene was dried by molecular sieves to minimize the addition of water, and then benzene was mixed with a mixture of purified monoolefins and paraffins (purified alkylating agent, see Example 1). The alkylation tests in the pilot plant were carried out in a fixed-bed isothermal reactor with 24-hour reaction cycles, followed by catalyst regeneration cycles by washing with benzene for the same period of time. The standard cycle consisted of a 24-hour reaction cycle at 140 ° C, a LHSV = 11 h ^-1 and a benzene: olefin molar ratio of 30: 1, followed by a benzene washing cycle for the same period of time. Mass of catalyst, flushing conditions, etc. are summarized in table 8.

Table 8 Working conditions The size of the extruded particles, mm · mm 1.5 × 5.0 The volume of catalyst, cm ³ 122 The reaction temperature, ° C 100-150 Regeneration temperature, ° С 260 Reaction pressure, MPa (kgf / cm ² ) 2 (20) Regeneration pressure, MPa (kgf / cm ² ) 4 (40) COSG reaction, hour ^-1 4-11 COSG regeneration, hour ^-1 one The benzene / olefin molar ratio 10-30

The composition of the feedstock, which relates to a mixture of olefins and paraffins, is presented in table 9.

Table 9 Compound The percentage, wt.% In the mixture n-C10 14.8 n-C11 31,0 n-C12 26.1 H-C13 18.2 n-C14 <0.9 C10 olefin 1.3 C11 olefin 3.2 C12 olefin 3,1 C13 olefin 2,3 C14 olefin <0.1 Aromatic compounds <0.1

This purified mixture of paraffins and olefins (purified alkylating agent, see Example 1) was mixed with dried benzene to achieve the desired benzene: olefin molar ratio. Catalyst tests were performed in four different reaction cycle sequences. After each reaction cycle, the alkylation effluent (crude alkylate, including formed alkylbenzene, unreacted benzene, paraffins and heavy alkylate) was distilled in three stages using three successive distillation columns (the first of these columns being operated at atmospheric pressure, while the other operated under vacuum). The first column was operated at atmospheric pressure and unreacted benzene was separated in its upper part, while the compounds from its lower part were fed into the second column. In the second column, paraffins were separated in its upper part, while compounds from its lower part were fed into the third column. In the third column, monoalkylbenzenes in its upper part and heavy alkylate in its lower part were separated. Tests (conducted with a gas chromatograph with a flame ionization detector (GC-FID)) relate to compounds fed to a third column. In all of the examples described in this patent, the chromatographic method, ref. U 698 was used. During the first sequence of reaction cycles, both catalysts (A and B) were independently tested under the same operating conditions. For each catalyst, the evaluation sequence consisted of seven reaction cycles carried out at a LHSV of 11 h ^-1 and a temperature of 130 to 140 ° C, followed by three cycles at 115 ° C with a LHSV of 4 h ^-1 . Next, a standard cycle was performed at 140 ° C and a LHSV of 11 h ⁻¹ to verify catalyst deactivation. In all these cycles, the benzene: olefin molar ratio was maintained at 30: 1. Each of these reaction cycles was followed by a regeneration cycle (washing cycle). All conditions and results are presented in Table 10. Note that a difference of up to 100% addition of monoalkylbenzenes and heavy alkylate corresponds to light by-products (lower than 5-phenyl-C ₁₀ ), while a difference up to 100% addition of branched alkylate and 2 -phenyl isomers corresponds to the internal isomers (3, 4, 5 and 6-phenyl).

Table 10 Cycle T, ° С HOUSING, hour ^-1 Conversion, mol.% Monoalkylbenzene, wt.% Heavy alkylate, wt.% Ramified alkylate, wt.% 2-phenyl isomers, wt.% BUT AT BUT AT BUT AT BUT AT BUT AT one 140 eleven 100.0 100.0 98.4 98.6 0.6 0.5 6.5 3,7 18.7 19.3 2 140 eleven 100.0 100.0 98.5 98.6 0.5 0.4 6.4 3.6 18.5 19.2 3 140 eleven 100.0 100.0 98.8 98.8 0.3 0.3 6.3 3.6 18.5 19.2 four 130 eleven 99.9 99.9 98.4 98.5 0.7 0.5 5.7 3,7 18,4 19.1 5 130 eleven 99.9 99.9 98.4 98.5 0.7 0.5 6.0 3.9 18.3 19.1 6 130 eleven 99.9 99.9 98.5 98.7 0.6 0.4 5.8 3.8 18,4 19.1 7 140 eleven 100.0 100.0 98.5 98.6 0.5 0.4 6.9 3.9 18,4 19.2 8 115 4.0 100.0 100.0 98.3 98.4 0.8 0.7 5.1 3.3 18.5 19.0 9 115 4.0 100.0 100.0 98.3 98.4 0.8 0.7 5.2 3.4 18,4 19.0 10 115 4.0 100.0 100.0 98.4 98.6 0.8 0.7 5.2 3.4 18,4 19.1 eleven 140 eleven 100.0 100.0 98.4 98.5 0.6 0.5 6.8 3.9 18,4 19.2

During the second sequence of reaction cycles, kinetic tests of catalysts A and B were carried out to analyze their activity at lower temperatures. This sequence includes three reaction cycles carried out at a LHSV of 4 h ^-1 , but at the same time at 100 ° C, followed by a standard cycle (LHS = 11 h ^-1 , T = 140 ° C). In all these cycles, the benzene: olefin molar ratio was maintained at 30. All conditions and results are presented in table 11. Note that a difference of up to 100% addition of monoalkylbenzenes and heavy alkylate corresponds to light by-products (lower than 5-phenyl-C ₁₀ ), while the difference of up to 100% addition of branched alkylate and 2-phenyl isomers corresponds to the internal isomers (3, 4, 5 and 6-phenyl).

Table 11 Cycle T, ° С HOUSING, hour ^-1 Conversion, mol.% Monoalkylbenzene, wt.% Heavy alkylate, wt.% Ramified alkylate, wt.% 2-phenylisomers. wt.% BUT AT BUT AT BUT AT BUT AT BUT AT one one hundred 4.0 99.9 99.9 98.3 98.4 1,1 0.9 3.8 2.5 18.2 18.8 2 one hundred 4.0 99.9 99.9 98.5 98.5 0.9 0.8 3.8 2.5 18.2 18.8 3 one hundred 4.0 99.9 99.9 98.6 98.7 0.8 0.7 4.0 2.6 18.2 18.7 four 140 11.0 100.0 100.0 98.5 98.6 0.6 0.5 6.7 3.8 18,4 19.2

The third sequence of reaction cycles includes six reaction cycles performed at varying LHSV, temperature and molar ratio of benzene.-olefin to analyze the effect of the latter variable on conversion and selectivity of the reaction. The conditions and results are shown in table 12.

Table 12 Cycle T, ° С HOUSING, hour ^-1 Benzene olefin Conversion,
mol% Monoalkyl-benzene, wt.% Heavy alkylate, wt.% Ramified alkylate, wt.% 2-phenylisomers. wt.% BUT AT BUT AT BUT AT BUT AT BUT AT one 120 3,1 10 100.0 100.0 94.9 95.0 3.3 3.2 7.6 4.9 18.8 19.2 2 120 3.6 fifteen 100.0 100.0 96.6 96.8 1.9 1.7 6.7 4.4 18.8 19.2 3 120 4,5 25 100.0 100.0 97.2 97.5 1.3 1,0 6.5 4.2 18.7 19.2 four 120 4.9 thirty 100.0 100.0 98.0 98.1 0.7 0.6 5.9 3.8 19.1 19.6 one 140 3,1 10 100.0 100.0 94.4 94.6 4.0 3.8 9.1 5.2 19.0 19.5 2 150 3,1 10 100.0 100.0 94.9 95.0 4.0 3.8 10,2 5.8 18.9 19.3

During the fourth sequence of reaction cycles, both catalysts were tested to analyze their deactivation rate. With the goal of stimulating catalyst deactivation, after the initial standard cycle (LSS = 11 h ^-1 , T = 140 ° C), the usual 24-hour reaction period was extended to 72 hours without a standard benzene wash every 24 hours. During all these cycles, the benzene: olefin molar ratio was maintained at 30. The activity of the catalyst was analyzed in terms of conversion. All results and conditions are shown in table 13.

Table 13 Reaction time, hour Temperature ° C HOUSING, hour ^-1 Catalyst A Conversion Catalyst B Conversion 24 140 eleven 100.0 100.0 thirty 140 eleven 100.0 100.0 36 140 eleven 100.0 100.0 42 140 eleven 99.9 99.9 48 140 eleven 99.9 99.9 54 140 eleven 99.5 99.7 60 140 eleven 98.9 99.6 66 140 eleven 98.2 99.5 72 140 eleven 97.1 99.5

As can be seen in table 10, the activity of catalyst B is equal to the activity of catalyst A in all sequences of 24-hour reaction cycles, since, like catalyst A, catalyst B provides conversion levels from 99.9 to 100% during cycles at "high »Temperature (from 115 to 140 ° C). In terms of conversion, it can be observed that also during cycles at a "low" temperature (100 ° C, table 11), said catalyst B can provide an activity of 99.9%, which is equal to the activity of catalyst A. Moreover, table 12 shows that both catalysts also give a 100% conversion when LHSV, temperature and the benzene: olefin molar ratio are varied within the industrial operating conditions. In terms of catalytic activity, the great advantage of catalyst B is that it provides a short-term level of activity (24-hour cycles) equal to that for catalyst A, however, catalyst B is also able to maintain high degrees of conversion (above 99.5%) for longer periods of time (30% longer time) without any washing cycles between these periods, as can be seen from the stimulated deactivation tests described in table 13. Higher catalyst stability at d decontamination from contaminants allows you to extend the duration of the reaction cycles and reduce the number of regeneration cycles required for operation at high degrees of conversion, in relation to the catalyst A. This provides for the same period of operation of catalysts A and B a longer net operating time when using the reaction time of catalyst B ( high productivity of catalyst B), as well as a decrease in the total cost of regeneration (fewer washing cycles for a specified period of time and), mainly related to energy consumption.

Compared with catalyst A, in addition to equivalent activity and greater stability during deactivation, catalyst B provides higher selectivity with respect to the desired linear monoalkylated products. Thus, catalyst B provides an average of 30-35% less branched alkylate and 10-18% less heavy alkylate (mainly dialkylbenzenes) than catalyst A. Reducing both undesirable by-products entails two technological advantages over with catalyst A.

The main advantage of catalyst B relates to a decrease in the production of branched alkylate, therefore there is a proportional decrease in the “internal Quaternary carbon atoms”. A second advantage associated with catalyst B with respect to catalyst A is that catalyst B provides a lower amount of heavy alkylate. By reducing the final heavy alkylate content, there is an increase in the use of raw materials during the process of forming monoalkylated substances (dialkylbenzenes use an additional olefin chain as compared to the monoalkylbenzene molecule). Moreover, the quality of the final product is significantly improved, since the indicated heavy alkylate does not manifest itself as effectively as monoalkylated substances in the washing process, and the heavy alkylate often interferes with the formation of chromophore by-products during the final sulfonation stage, therefore, as can be seen in Example 6 LAB can be obtained with lower color after sulfonation (relative to 3 units on the Cletta-Summerson scale).

Example 3

This example relates to the benefits of using a purified alkylating agent (the purified mixture of olefins and paraffins in Example 1) during the alkylation step. Moreover, this example relates to the advantages of using a catalyst based on zeolite Y with a higher content of rare earth metals (12 wt.% Rare earth metals in the final catalyst, catalyst B from example 2) compared to a catalyst based on zeolite Y with a lower content of rare earths metals (7 wt.% rare earth metals in the final catalyst, catalyst A from example 2) using a purified alkylating agent.

The alkylation reaction was carried out with the catalysts A and B described in Example 2. In this case, purified and crude alkylating agents were used for each catalyst in order to detect differences in the characteristics of the catalysts. After purification of the alkylating agent (and over 95% of the aromatic compounds were eliminated), the mixture of olefins and paraffins was mixed with dried benzene to obtain the selected molar ratio. This mixture was then used as a feed during the alkylation step. The operating conditions of the alkylation step are shown in table 14.

Table 14 Temperature ° C 140 Pressure, MPa (kgf / cm ² ) 2 (20) HOUSING, hour ^-1 eleven The benzene / olefin molar ratio thirty

Another test was carried out to analyze the effects that the purification step has on the distribution of products, while maintaining all operating parameters, but at the same time using a crude mixture of an alkylating agent. On the other hand, the crude alkylate distillation process, which forms the outlet stream of the alkylation reactor, was carried out to separate benzene, paraffins, monoalkylbenzenes and heavy alkylate, and this process is equivalent to the process defined in example 2. GC analysis of the stream was carried out, which was fed to the third column ( method U 698). Light elements were analyzed by GC-PID at the output of the first column.

The distribution of the product in connection with the alkylation of a purified and crude mixture with catalysts A and B is presented in table 15.

Table 15 Product distribution Refined mixture Crude mixture BUT AT BUT AT Monoalkylbenzene, wt.% 98.6 98.7 94.7 95.2 Heavy alkylate, wt.% 0.5 0.4 3,7 3,5 Light by-products, wt.% 0.9 0.9 1,6 1.3

As can be seen in table 15, in comparison with the crude mixtures, the amount of heavy alkylate obtained using purified mixtures is reduced by 86% with catalyst A and reduced by 89% with catalyst B. It is also seen that the purification of the paraffin / olefin mixture contributes to a decrease in light by-products, and this decrease is slightly higher with catalyst A (decrease 44%) than with catalyst B (decrease 30%). In any case, it has been shown that purification of the paraffin / olefin mixture causes a significant reduction in the formation of undesirable by-products (above 85% with both catalysts). In addition, in both purified and unrefined mixtures, catalyst B provides fewer light and heavy by-products than catalyst A.

Example 4

This example relates to a higher stability achieved during the deactivation of a zeolite Y catalyst with the addition of a higher content of rare earth metals (12 wt.% Rare earth metals in the final catalyst, catalyst B from example 2) compared to a zeolite Y catalyst with by adding a lower content of rare earth metals (7 wt.% rare earth metals in the final catalyst, catalyst A from example 2), when the first is used as a catalyst for the alkylation of benzene purification nnym alkylating agent. A long sequence of reaction cycles was performed for both catalysts A and B to analyze the degree of their deactivation. In contrast to the case of “reversible” decontamination (implying that it can be eliminated by washing), tested in Example 2 (table 13), in this case the goal is to study “irreversible” deactivation, i.e. decontamination, which does not disappear after regeneration of the catalyst. All thirty cycles were performed at a LHSV = 11 hour ^-1 , T = 140 ° C and a benzene: olefin molar ratio of 30 (a mixture of purified olefins and paraffins, as described in Example 1, the composition of the mixture is described in Tables 5 and 9, other working conditions as indicated in table 8). After each 24-hour reaction cycle, a benzene washing cycle was performed for 24 hours. The results are summarized in table 16 and represent the average value for the considered cycles.

Table 16 Cycles Average conversion BUT AT 1-10 99.6 99.8 11-20 99.6 99.8 21-30 99.6 99.8

As can be seen in table 16, for this entire sequence of reaction / regeneration cycles, the average conversion with catalyst B remains uniform and constant (99.8%), while its value is higher than that provided by catalyst A. None of the catalysts showed any loss of irreversible activity during the thirtieth cycle compared with the initial cycles. Due to the fact that catalyst B operates at higher activity rates than catalyst A, and since no irreversible deactivation has been detected, it can be confirmed that the resistance of catalyst B to irreversible deactivation is at least equal to that for catalyst A. This means that catalyst B has a lifetime equal to or even greater than catalyst A.

Example 5

This example relates to the advantages of using a catalyst based on zeolite Y containing a high content of rare earth metals and sodium (catalyst B from example 2), compared to using a catalyst based on zeolite Y containing a low content of rare earth metals and sodium (catalyst A from example 2 ), in the operation of two parallel fixed-bed isothermal reactors used to produce alkylate with a controlled content of 2-phenylisomers. One of the reactors is loaded with one of the catalysts A or B, and the other reactor is loaded with non-fluorinated industrial crystalline mordenite, called catalyst C, by adjusting the distribution of the pre-purified feed (as in Example 1) between the two reactors and mixing the resulting effluents to obtain a controlled content of 2-phenyl isomer in received stream.

A certain amount of catalyst A was placed in one of the fixed-bed reactors (called layer 1), while the other layer (called layer 2) was loaded with a certain amount of non-fluorinated industrial crystalline mordenite (catalyst C). The feed composition to both reactors was the same. The feed stream was formed by mixing a purified mixture of olefins and paraffins (composition of the mixture as described in table 5, example 1) with a suitable amount of dried benzene to obtain the desired benzene: olefin molar ratio. Always maintained a constant flow rate of the specified source stream. After that, the stream was divided into two substreams by means of a three-way valve. Each stream was fed to the reactor (after the preheating step) to meter a variable flow rate to each reactor by adjusting the valve (but keeping the total flow constant). The effluent from each reactor (crude alkylate) was mixed, thereby obtaining a final effluent that was analyzed by GC-FID (after separation of benzene, paraffins and heavy alkylate from monoalkylbenzenes by the distillation process as described in Example 2). In this example, both the feed composition, as well as the reaction pressure, were kept constant for both reactors, however, the reaction temperature was different in each reactor (since Y zeolites are more active than mordenite) and the feed rates were varied to change the final content 2 phenylisomer. The same method was carried out by loading layer 1 with catalyst B (the same mass of catalyst B as the mass of catalyst A used in the previous test) and loading layer 2 with the same amount of catalyst C as the amount used in the previous test to see differences in the ratio characteristics of both catalysts based on zeolites Y (A and B). Operating conditions are shown in table 17.

Note that the hourly volumetric flow rate of the fluid (CFS) for each reactor varies with a change in the percentage of initial feed dosed to each reactor from 2.7 hours ^-1 (when 25% of the initial feed passes through the specified reactor) to 11 hours ^-1 (when 100% of the initial feed passes through one separate reactor).

Table 17 Catalytic layer one 2 Loaded catalyst A or b FROM The diameter of the particle (extruded in the form of a cylinder), mm 1.5 × 5.0 1.5 × 5.0 The volume of catalyst, cm ³ 122 122 The reaction temperature, ° C one hundred 140 Reaction pressure, MPa (kgf / cm ² ) 2 (20) 2 (20) COSG reaction, hour ^-1 2.7-11.0 2.7-11.0 The benzene / olefin molar ratio thirty thirty

The distribution of the product in the final effluent when the feed streams are changed is shown in table 18.

Table 18 % began. feed, dose. to each reactor (layer 1 / layer 2) Total conversion,% The content of 2-phenylisomer, wt.% Heavy alkylate, wt.% Branched alkylate, wt.% BUT AT BUT AT BUT AT BUT AT 100/0 99.9 99.9 18.2 18.8 0.9 0.7 6.3 2.5 75/25 99,4 99.5 30.1 31.6 0.9 0.7 5.7 2,8 50/50 99.1 99,2 43.0 44,4 0.9 0.8 5.1 3,1 25/75 98.7 98.7 55,2 57.2 0.9 0.8 4.4 3,5 0/100 98.3 98.3 70.0 70 0.9 0.9 3.8 3.8

As can be seen in table 18, a change in the flow rate fed to each reactor means a change in the final content of 2-phenylisomer in monoalkylbenzene from 18 wt.% (Obtained when the entire initial supply passes through layer 1) to 70 wt.% (Obtained, when the entire initial feed passes through the mordenite layer). This confirms that the configuration of the method in which catalyst B is used in layer 1 gives a net conversion slightly higher than the pure conversion using catalyst A, due to the higher activity of catalyst B at low temperatures. Regarding the formation of 2-phenylisomers, there are no significant differences between the results obtained using catalysts A or B. As for the formation of heavy alkylate, it can be seen that for the layer 1 / layer 2 dosing ratio, the feed rates are lower or equal to 50/50, with the use of catalyst B in layer 1, the resulting final content of heavy alkylate is lower (11 to 20%) than the amount of heavy alkylate obtained using catalyst A in layer 1, which means better use of raw materials.

The most significant result from table 18 relates to the production of branched products. Table 18 shows that when using catalyst B in layer 1, the final amount of branched alkylate in the stream obtained by mixing the effluents from layers 1 and 2 is much lower than the final amount of branched alkylate obtained using catalyst A. The same range 2- phenyl isomers can be obtained using catalyst A or B, but when catalyst B is used, the conversion and selectivity conditions are improved and the amount of branched alkylates in the final product (average content of 3.1%) is significantly shaetsya (60%), the amount of branched alkylates in the final product does not exceed 3.8% in any case. The percentage of branched alkylate obtained using the BC catalyst system is within the same level as the percentage of branched alkylate obtained using existing HF and DETAL technologies, which, as noted in the prior art section, produce LAB biologically degradable quickly and completely.

Example 6

This example relates to the advantages of purifying monoalkylbenzene from the alkylation and purification of the crude alkylate (described in Example 5) before the sulfonation step to minimize color after sulfonation of the final sulfonic acid. This example also relates to the advantage of using a catalyst based on zeolite Y with a high content of rare earth metals and sodium (catalyst B from example 2) compared to using a catalyst based on zeolite Y with a low content of rare earth metals and sodium (catalyst A from example 2), moreover, this comparison is based on indicators of lower levels of final color after sulfonation.

As described in Examples 2-5, a purified mixture of olefins and paraffins mixed with dried benzene was used as a feed. A molar ratio of benzene: olefin of 20: 1 was chosen. Alkylation was carried out using two fixed-bed isothermal parallel reactors as described in Example 5. Catalyst A or B was loaded into one of the layers (layer 1), and catalyst C described in example 4 was loaded into another layer. The operating conditions during the alkylation step were exactly the same as the operating conditions shown in Example 5 (Table 17). A feed dosage of 50% of the initial flow for each reactor was selected in the configuration in which the loading of layer 1 was carried out by catalyst A, as well as in the configuration in which the loading of catalyst 1 was loaded into layer 1. The crude alkylate formed by mixing the effluents of layers 1 and 2, was purified by fractionation to separate monoalkylbenzenes. The distillation (purification) of the crude alkylate was slightly different from the purification used in the previous examples. In this example, four distillation columns were used. The first column was operated at atmospheric pressure and unreacted benzene was separated in its upper part, while compounds from its lower part were fed into the second column. In the second column, which worked under vacuum, paraffins were separated in its upper part, while the compounds from its lower part were fed into the third column. In the third column, which operated under vacuum, monoalkylbenzene was separated in its upper part, and the heavy alkylate in its lower part was separated. Monoalkylbenzene obtained from the top of the third column, in which traces of heavy alkylate were detected, was applied to a cleaning layer responsible for eliminating chromophore precursors. After cleaning, the effluent was fed to the fourth distillation column. In this column, light by-products formed during the purification step (mainly benzene obtained through the transalkylation reaction, at parts per million) were separated in its upper part, while the compounds found in the lower part were highly pure monoalkylbenzenes. These high-purity monoalkylbenzenes were then sulfonated in a single-tube falling film reactor, the SO ₃ sulfonating agent being dissolved in nitrogen, and these monoalkylbenzenes were aged and hydrolyzed to complete the reaction.

As indicated in the previous paragraph, the purification step was carried out by treating monoalkylbenzene (obtained by fractionating the crude alkylate) in a treatment unit (reactor) with a fixed bed in which a certain amount of industrial acid clay was placed. In this example, the clay used is characterized by a mass ratio of silica to alumina of 4.9: 1.0, 1.4 wt.% K ₂ O and 1.2 wt.% MgO are partially neutralized, and is also characterized by a content of 2.9 wt. Wt.% Fe ₂ O ₃ and 0.5 wt.% TiO ₂ . This clay was pre-activated by directing a stream of hot inert gas to remove adsorbed water. The conditions of activation and operation are given in table 19.

Table 19 Cleaning temperature, ° С 110 COSJ cleaning, hour ^-1 3 Activation temperature, ° С 120 COSG activation, hour ^-1 2 Activation time, hour 12 Activation gas N ₂

The sulfonation conditions of the purified and crude monoalkylbenzenes obtained by the combination of catalysts A-C and B-C are shown in Table 20.

Table 20 The molar ratio of SO ₃ / LAB 1.10: 1 Reaction time, hour 1,5 The reaction temperature, ° C 40-45 Holding time, hour one Holding temperature, ° С 40-45 Hydrolysis time, hour 0.5 The hydrolysis temperature, ° C 40-45

The final color after sulfonation of the obtained linear alkylbenzenesulfonates (LAS) (called LAS A-C, if monoalkylbenzene comes from alkylation with catalysts A-C, and LAS B-C, if monoalkylbenzene comes from alkylation with a combination of catalysts B-C) were analyzed using a colorimeter Cletta-Summerson. To assess the effect of the purification step on the final color after sulfonation using catalysts A and B, monoalkylbenzene was also sulfonated under the same conditions without the clay purification step. The color of the sulfonated crude monoalkylbenzene (LAS from crude monoalkylbenzene) and the color of the sulfonated purified monoalkylbenzene (LAS from purified monoalkylbenzene) in alkylates prepared with a combination of catalysts A-C and A-B are shown in Table 21.

Table 21 Sulfonate Chroma after sulfonation (Clette-Summerson scale) LAS A-S LAS VS Crude Monoalkylbenzene LAS 23 19 Purified Monoalkylbenzene LAS <7 <7

As shown in table 21, purification of monoalkylbenzene using acidic clay can significantly reduce color after sulfonation of LAS from purified monoalkylbenzene alkylate compared to LAS from crude monoalkylbenzene (at least 70-80% lower, color after sulfonation below 7 cannot be measured using a scale Cletta-Summerson). Note that the LAS sample from crude monoalkylbenzene obtained by combining catalysts BC shows a color after sulfonation that is significantly lower (17% lower) than the color after sulfonation obtained by combining catalysts A-C. This means that during the alkylation step, catalyst B provides fewer chromophore precursors than catalyst A. By decreasing the color after sulfonation, the quality of the neutralized final product is increased, especially when the final product is used in the liquid composition of the detergent, since this color may affect on the visual effect of the coloring matter added to the detergent composition.

Example 7

This example shows the advantages of adding a hydrotropic precursor (prepared as described in Example 1) to monoalkyl benzene (obtained by fractionating the crude alkylate) before the purification step of said alkyl benzene (explained in Example 6), after which the resulting alkylate is separated and sulfonated. A hydrotrop itself is formed by sulfonation (and subsequent neutralization) of the hydrotropic precursor in the sulfonation step, either separated or mixed with linear monoalkylbenzene. In addition, the hydrotropic effect of LAS obtained with a combination of catalysts A – C and B – C was compared.

The effluent (crude alkylate) streams of layers 1 and 2 (using A — C and B — C in various operations as in Example 5) were mixed and then distilled in a manner equivalent to that described in Examples 5 and 6 to separate monoalkylbenzenes. A hydrotropic precursor was added to these monoalkylbenzenes, after which the resulting mixture was purified with acid clay under the same conditions as in Example 8, and the resulting effluents were distilled to separate light by-products of the final alkylate. After sulfonation of these alkylates, they were finally neutralized with an aqueous solution of sodium hydroxide in a stoichiometric amount.

To evaluate the hydrotropic effect depending on the content of the 2-phenylisomer, six samples of purified monoalkylbenzene with different contents of 2-phenylisomers were obtained in the alkylation stage (as defined in Example 5) for each combination of catalysts indicated in Examples 3 and 4 (A-C and B-C). Samples were designated S1 (A-C and B-C), S2 (A-C and B-C) and S3 (A-C and B-C) according to the content of 2-phenyl isomers and their origin. The costs were regulated when working with configurations A-C and B-C to obtain the same content of 2-phenyl isomers. Control tests (without adding a hydrotrope) and tests with sodium xylene sulfonate (SPH) were performed with an alkylate obtained from A-C and B-C systems with the same content of 2-phenyl isomers as the above S1, S2 and S3, so that the same designation used to distinguish the content of 2-phenylisomer. The results are shown in table 22.

Table 22 S1 (A-C and B-C) S2 (A-C and B-C) S3 (A-C and B-C) 2-phenyl isomers, wt.% 18.8 58.1 70.0

The effect of hydrotrope dissolution was evaluated in terms of the cloud point during cooling (TPO) of the final sulfonated and neutralized product. The specified product was diluted with water to obtain the usual industrial concentrations (20, 25, 30 wt.% In water). To observe the effect of the hydrotropic precursor, samples were prepared with 90 wt.% Monoalkylbenzene and 10 wt.% Hydrotropic precursor. In addition, pure samples were prepared, that is, samples without the addition of a hydrotropic precursor. Thus, samples were prepared with 100% of the product obtained from system AB, and samples with 100% by-product of the above system BC with the same content of 2-phenylisomers as the samples in which the hydrotropic precursor was added. Another well-known hydrotrope - sodium xylene sulfonate (SPH) was added to samples without a hydrotropic precursor (90% pure sodium alkylbenzenesulfonate containing 2-phenyl isomers equivalent to the content in other tests and 10% SPH) and then it was diluted with water to the same industrial concentrations as previous samples. The results are shown in table 23.

Table 23 Active material in a cleaning composition (wt.% In water) twenty% 25% thirty% Cloud point at cooling, ° С Alkylate from AC system 100% S1 (A-C) 8 16 24 90% S1 (A-C) + 10% SPF (sodium xylene sulfonate) 7 fourteen twenty 90% S1 (A-C) + 10% one 7 fourteen

hydrotropic precursor 100% S2 (A-C) 17 twenty ( ^* ) 90% S2 (A-C) + 10% KCH (sodium xylene sulfonate) fourteen 17 ( ^* ) 90% S2 (A-C) + 10% hydrotropic precursor 13 16 twenty 100% S3 (A-C) 16 twenty 24 90% S3 (A-C) + 10% KCH (sodium xylene sulfonate) 12 fifteen 17 90% S3 (A-C) + 10% hydrotropic precursor 7 9 13 Alkylate from the BC system 100% S1 (B-C) 9 17 24 90% S1 (B-C) + 10% SPF (sodium xylene sulfonate) 7 fifteen twenty 90% S1 (BC) + 10% hydrotropic precursor one 7 fourteen 100% S2 (B-C) eighteen twenty ( ^* ) 90% S2 (B-C) + 10% KCH (sodium xylene sulfonate) fourteen 17 ( ^* ) 90% S2 (B-C) + 10% hydrotropic precursor 13 16 twenty 100% S3 (B-C) 16 twenty 24 90% S3 (B-C) + 10% KCH (sodium xylene sulfonate) 12 fifteen 17 90% S3 (B-C) + 10% hydrotropic precursor 7 9 13 ( ^* ) Turbid at room temperature (T = 25 ° C).

From table 23 two main conclusions can be drawn. Firstly, it can be seen that for samples with a low 2-phenyl content and without hydrotrope (samples 100% S1 and 100% S2), the cloud point obtained for the alkylate from system A-C is slightly higher than the cloud point of system B- C, although the addition of hydrotropes tends to lower these cloud points to the same levels (and at high concentrations of 2-phenylisomers this difference disappears). This fact is apparently associated with a high content of branched monoalkyl sulfonates (more soluble than linear equivalent compounds) in the AB system. The second conclusion refers to the fact that the ability of the hydrotrope provided in this application to reduce the cloud point is much higher than that of the SPF, especially for samples with a very low (18%) or very high (70%) content of 2-phenylisomers for both products catalytic system AC, and for both products of the system BC. Therefore, we can conclude that the product of system BC is practically as soluble as the product of system AB (in fact, equally soluble for high concentrations of 2-phenylisomers), and that the addition of the hydrotrope provided in this application reduces the TPO of the catalytic by-product systems A-B and B-C to the same levels and much lower than the values obtained using an industrial hydrotrope, such as SPE.

Example 8

This example illustrates the advantages of a zeolite Y catalyst having a high content of rare earth metals and sodium (catalyst B in Example 2) with respect to the use of a zeolite Y catalyst having a low content of rare earth metals and sodium (catalyst A in Example 2) with performing alkylation of benzene with long chain linear alpha olefins (range C ₂₀ -C ₂₂ ), compared with the results obtained using HF, a catalyst used for a long time on an industrial scale abe for this method.

Benzene was dried with a molecular sieve to minimize the addition of water and then mixed with a mixture of long chain linear alpha olefins. The alkylation tests in the pilot plant in the case of a solid catalyst were carried out in a thin-layer isothermal reactor with 24-hour reaction cycles, followed by washing cycles with benzene for the same period. The standard cycle includes a 24-hour reaction cycle with a benzene: olefin molar ratio of 50: 1, followed by a benzene washing cycle for the same period of time. Operating conditions are shown in table 24.

Table 24 Catalyst BUT Particle Diameter mm mm 0.5-1.25 The volume of catalyst, cm ³ 122 The reaction temperature, ° C 140-150 Regeneration temperature, ° С 260 Reaction pressure, MPa (kgf / cm ² ) 2 (20) Regeneration pressure, MPa (kgf / cm ² ) 4 (40) COSG reaction, hour ^-1 4-8 COSG regeneration, hour ^-1 one Reaction time, hour 24 Regeneration time, hour 24 The benzene / olefin molar ratio fifty

The composition of the mixture of alpha-olefins used as a feed is presented below in table 25.

Table 25 Compound wt.% <C ₂₀ olefin 0.1 C ₂₀ olefin 43.7 C ₂₂ olefin 35.3 C ₂₄ olefin 19.1 > C ₄₀ olefin 0.7

Twelve reaction alkylation cycles were carried out using zeolites Y A and B of Example 2. The first three cycles were performed with a LHSV of 8 h ⁻¹ at T = 150 ° C (cycle 1). Then three cycles with LSS 6 h ^-1 at T = 150 ° C (cycle 2). The last four cycles were performed with LSSV 8 h ^-1 , two of them at T = 150 ° C and the last two at a lower temperature T = 140 ° C (cycle 3). All these cycles were performed to analyze the effect of temperature and space velocity on the catalyst yield. Products were analyzed by gas chromatography (GC) with a flame ionization detector (PID).

Alkylation with HF was carried out batchwise in a cooled reactor with continuous stirring, since alkylation is an exothermic reaction and it is necessary to remove heat from the reactor to maintain a constant required reaction temperature, which is typical of the prior art. A certain amount of the previously considered linear alpha-olefin mixture (composition shown in Table 25) mixed with dry benzene was introduced into the reactor to obtain the desired benzene: olefin molar ratio. The mixture of benzene and olefins was preheated to the selected reaction temperature. Then, a certain volume of liquid HF was introduced into the reactor until the selected volume ratio HF: olefin was reached. The reaction time was chosen so that it was 10 minutes to obtain a LHSV = 6 h ^-1 , which is common for known alkylation processes with HF. The operating conditions of the alkylation reaction with HF are shown in table 26.

Table 26 Catalyst Hf The reaction temperature, ° C 60 Reaction time, min 10 Volume ratio HF / olefin one The benzene / olefin molar ratio 10

The results presented in table 27 correspond to the average distribution of products (monoalkylbenzenes and by-products, including light by-products and heavy by-products, after separation of unreacted benzene) of such cycles in which solid catalysts A and B were used with different LOC conditions and temperatures (called cycles 1, 2 and 3). Results corresponding to HF technology are included at the bottom of Table 27 to compare the yields for HF and solid catalyst.

Table 27 Catalyst Cycle ChOSZh, hour " ¹ T, ° С Conversion% Monoalkylbenzene, wt.% All by-products, wt.% one 8 150 99.7 99.6 0.37 BUT 2 four 150 99.9 99.8 0.23 3 four 140 99.8 99.7 0.26 AT one 8 150 99.8 99.7 0.29 2 four 150 99.9 99.8 0.23 3 four 140 99.8 99.7 0.25 Hf - 6 60 99.9 99.7 0.30

As can be seen in table 27, the activity of zeolites Y containing rare earth metals A and B as additives is very similar (slightly higher for catalyst B), since the olefin conversion is always higher than 99.7%. In the analysis of the obtained by-products, both catalysts A and B, as well as HF, showed high selectivity for minimizing light by-products and heavy alkylate. The amount of all by-products obtained by solid catalysts A and B is below 0.4 wt.% In the three cycles evaluated, and in cycles 2 and 3 even better than when using HF. Therefore, both catalysts based on zeolites Y with rare earth metals (A and B) are equivalent to the catalyst used in industry (HF) in terms of conversion and selectivity towards monoalkylbenzenes.

The distribution of isomers corresponding to the previous experiments is presented in table 28. As in table 27, the line located in the lower part corresponds to the results related to the reaction with HF under operating conditions previously defined in table 26.

Table 28 Catalyst Cycle Branched alkylate, wt.% 2-phenyl, wt.% 3-phenyl, wt.% 4, 5, 6, 7-phenyl, wt.% BUT one 16.8 17.6 14.0 51.6 2 18.7 17.0 13,4 51.0 3 16,4 17.7 14,4 51.8 AT one 12.6 17.4 14.2 55.8 2 14.0 18.3 13.5 54,2 3 12.3 16.9 14.6 56.2 Hf - 12,4 19.9 12.1 55.8

In table 28, the distribution of isomers is similar when comparing the products of zeolites Y (A and B) with the products of HF. The main difference relates to the content of branched alkylate. As you can see, the amount of branched alkylate obtained using a zeolite with a low content (7%) of rare earth metals is approximately 27% higher than the amount obtained using HF as a catalyst. However, the amount of branched alkylate obtained with catalyst B is equal to and even lower (cycle 3) than that obtained with HF. Therefore, from this point of view, it is possible to obtain less branched alkylate with catalyst B than with catalyst A (25% less), and approximately the same amount as with the homogeneous catalyst used in industry (HF). Regarding the content of 2-phenylisomers, it can be seen that with the HF technology a slightly lower amount of 2-phenylisomers is obtained than with zeolites Y modified with rare earth metals (A and B).

Therefore, it can be seen that catalyst B is a catalyst equivalent to the HF catalyst in the method of alkylating benzene with pure alpha olefins (in terms of conversion, selectivity for monoalkylate and alkylates), and in addition, difficulties in handling a corrosive acid such as HF are avoided . Moreover, catalyst B improves the performance of catalyst A in this process by significantly reducing (by 25%) the production of branched alkylates.

Claims (19)

1. A method of obtaining a linear monoalkyl aromatic compound with a 2-phenylisomer content of from 18 to 70 wt.% By catalytic alkylation of an aromatic compound selected from the group consisting of toluene, xylene, benzene or mixtures thereof, a purified alkylating agent comprising monoolefins; the specified method includes the following stages:
1) alkylation of an aromatic hydrocarbon with monoolefins present in a purified alkylating agent by a combination of the following processes:
a) an alkylation process with a catalyst that provides a linear alkyl aromatic compound with a maximum content of 2-phenylisomers of 20 wt.%,
b) an alkylation process with a catalyst that provides a linear alkyl aromatic compound with a minimum content of 2-phenylisomers of 20 wt.%, including a MOR type zeolite, from 0.01 wt.% to 0.20 wt.% of at least one of metals selected from the group consisting of Li, Na, K, Mg or Ca, with a maximum Na content of 0.01%, and from 0 to 0.5 wt.% at least one of the metals selected from the group consisting of Ti, Zr, Hf;
2) fractionation of the effluent of stage (1) to separate unreacted aromatic hydrocarbons, straight chain alkanes containing from 8 to 30 carbon atoms, and the lightest and heaviest by-products from the target linear monoalkyl aromatic compounds;
3) purification of the fraction of linear monoalkyl aromatic compounds from stage (2),
characterized in that the catalyst, providing a maximum of 20 wt.% 2-phenylisomers, includes a zeolite type FAU, from 0.5 to 2 wt.% at least one of the metals selected from the group consisting of Li, Na, K, Mg or Ca, and rare earth metals in an amount of: from 4.5 to 10 wt.% La, from 1.2 to 4 wt.% Ce, from 0.5 to 1.5 wt.% Pr and from 2 to 3 wt. .% Nd. 2. A method for producing a linear monoalkyl aromatic compound according to claim 1, comprising preliminary steps:
catalytic dehydrogenation of straight chain alkanes containing from 8 to 30 carbon atoms;
selective hydrogenation of diolefins obtained as by-products in the previous step to monoolefins to obtain a starting alkylating agent;
purifying the starting alkylating agent obtained in the previous step, separating the non-linear products contained in the effluent of the previous step to obtain a purified alkylating agent, and
processing non-linear products separated in the previous step to form a hydrotropic precursor. 3. The method for producing a linear monoalkyl aromatic compound according to claim 1, wherein the catalyst providing a maximum of 20% of 2-phenylisomers comprises 0.9 wt.% Na. 4. The method for producing a linear monoalkyl aromatic compound according to claim 1, in which the catalyst, providing a maximum of 20% of 2-phenyl isomers, includes:
a) X-ray powder diffraction pattern, characterized in that the most intense diffraction peak appears at an angle of 2 θ corresponding to 6.2 °, and the remaining main peaks appear at an angle of diffraction of 2 θ corresponding to 23.6 °; 20.3 °; 21.6 °; 27.0 °; 31.3 °, arranged in order from highest to lowest intensity of the corresponding peaks;
b) the total molar ratio of silicon / aluminum is from 0.5: 1.0 to 3.0: 1.0;
c) the molar ratio of silicon / aluminum in the structural lattice from 1.5: 1.0 to 2.5: 1.0;
g) the total specific surface area (BET), comprising from 500 to 1000 m ² / g;
d) the area of micropores, comprising from 500 to 900 m ² / g;
e) a specific micropore volume of 0.1 to 0.3 ml / g;
g) the distribution of macropores, in which the diameter of the macropores is from 0.002 to 0.200 microns. 5. The method for producing a linear monoalkyl aromatic compound according to claim 1, wherein the aromatic hydrocarbon and purified alkylating agent are mixed before the alkylation reaction of step (1) in a molar ratio aromatic hydrocarbon: olefin of 5: 1 to 70: 1. 6. The method for producing a linear monoalkyl aromatic compound according to claim 1, wherein the mixture of an aromatic hydrocarbon and a purified alkylating agent comprises a maximum of 0.3 wt.% Non-linear compounds other than an aromatic hydrocarbon. 7. The method for producing a linear monoalkyl aromatic compound according to claim 1, wherein the mixture of aromatic hydrocarbon and purified alkylating agent comprises from 0 to 0.1 wt.% Water. 8. The method for producing a linear monoalkyl aromatic compound according to claim 1, wherein the alkylation reactions of step (1) are carried out simultaneously. 9. The method for producing a linear monoalkyl aromatic compound according to claim 1, wherein the catalyst used in the alkylation reaction is placed in the reactor in an arrangement selected from the group consisting of a fixed bed with one catalyst, a fixed bed with two completely mixed different catalysts, at least at least two different fixed beds with the same catalyst in each layer, at least two different fixed beds with different catalysts in each layer, a fluidized bed with one or olee different catalysts, a slurry reactor with one or more different catalysts. 10. The method of producing a linear monoalkyl aromatic compound according to claim 1, wherein the alkylation process is carried out in a reactor configuration that includes at least one of the reactor configurations selected from the group consisting of an independent reactor, at least two parallel reactors, at least two serial reactors and combinations of these configurations. 11. The method for producing a linear monoalkyl aromatic compound according to claim 1, wherein the purification step (3) is performed by selective absorption and / or hydrogenation and / or fractionation. 12. The method for producing a linear monoalkyl aromatic compound according to claim 11, in which selective adsorption is performed by means of a selective clay-based adsorbent. 13. The method of obtaining a linear monoalkylaromatic compounds according to item 12, in which the clay includes:
a) the total molar ratio of silicon / aluminum is from 3: 1 to 5: 1;
b) from 1 to 4 wt.% Fe ₂ About ₃ ;
C) from 0.5 to 2 wt.% K ₂ O;
g) from 0.2 to 2 wt.% MgO;
d) from 0.1 to 1 wt.% TiO ₂ ;
e) from 1800 to 2500 ppm Na;
g) specific surface area, expressed as BET surface area, from 150 to 500 m ² / g;
h) the total pore volume from 0.1 to 2.0 ml / g;
i) the distribution of macropores, in which the diameter of the macropores is from 0.002 to 0.080 microns. 14. The method for producing a linear monoalkyl aromatic compound according to claim 1, wherein the olefins of step (1) are linear α-olefins. 15. The method of producing a linear monoalkyl aromatic compound according to 14, in which the α-olefins of stage (1) include from 9 to 30 carbon atoms. 16. The method for producing a linear monoalkyl aromatic compound according to claim 1, wherein the reaction temperature is from 20 to 400 ° C. 17. The method of producing a linear monoalkyl aromatic compound according to claim 1, in which the space velocity is from 1 to 15 h ^-1 . 18. A method of producing a linear alkyl sulfonate, comprising obtaining a linear monoalkyl aromatic compound according to any one of claims 1 to 17 and a step for sulfonation and neutralization of the obtained monoalkyl aromatic compound. 19. The method of producing a linear alkyl sulfonate according to claim 18, wherein said neutralization is performed in the presence of an alkaline substance comprising one or more cations selected from the group of: Na, K, NH ₄ ⁺ , Mg, Ca, Ba or substituted ammonium alkali.

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