Method of etherification

Abstract

To provide methods of etherification.SOLUTION: Embodiments of the present disclosure are directed towards methods of etherification including modifying a zeolite catalyst with silica to provide a silica modified zeolite catalyst; and contacting the silica modified zeolite catalyst with an olefin and an alcohol to produce a monoalkyl ether.SELECTED DRAWING: None

Description

[Technical Field]

[0001] Embodiments of the present disclosure relate to methods for etherification, and more specifically, embodiments relate to methods for etherification that include modifying a zeolite catalyst with silica to provide a silica-modified zeolite catalyst, and producing a monoalkyl ether by contacting the silica-modified zeolite catalyst with an olefin and an alcohol. [Background technology]

[0002] Monoalkyl ethers are useful in many applications, such as solvents, surfactants, and chemical intermediates. Industry continues to focus on developing novel and improved materials and / or methods that can be used to produce monoalkyl ethers. [Overview of the project]

[0003] This disclosure provides a method for etherification, which includes modifying a zeolite catalyst with silica to provide a silica-modified zeolite catalyst having a silica content of 15 to 50 weight percent based on the total weight of the silica-modified zeolite catalyst, and producing a monoalkyl ether by contacting the silica-modified zeolite catalyst with an olefin and an alcohol.

[0004] The above summary of this disclosure is not intended to describe each disclosed embodiment or all implementations of this disclosure. More specifically, this specification illustrates exemplary embodiments. In several places throughout this application, guidance is provided through lists of examples, which can be used in various combinations. In all cases, the enumerated lists serve only as representative groups and should not be construed as exclusive lists. [Modes for carrying out the invention]

[0005] A method for etherification is disclosed herein. This method includes modifying a zeolite catalyst with silica to provide a silica-modified zeolite catalyst, and producing a monoalkyl ether by contacting the silica-modified zeolite catalyst with an olefin and an alcohol.

[0006] Advantageously, the etherification methods disclosed herein, as further discussed herein, can provide improved, i.e., higher monoalkyl ether selectivity compared to etherification without silica-modified zeolite catalysts. Improved monoalkyl ether selectivity can be desirable in many applications, such as providing chemical intermediates. For example, monoalkyl ethers can be used in the production of surfactants by ethoxylation processes, and monoalkyl ethers can have a desirable effect on the properties of surfactants compared to dialkyl ethers, for example, which may have undesirable effects on the properties of surfactants.

[0007] Furthermore, the etherification methods disclosed herein, as further discussed herein, can provide improved, i.e., less dialkyl ether selectivity compared to etherification without silica-modified zeolite catalysts. Improved dialkyl ether selectivity may be desirable for many applications, such as the production of surfactants by ethoxylation processes, where dialkyl ethers may have undesirable effects on the properties of surfactants compared to, for example, monoalkyl ethers.

[0008] Zeolite catalysts are crystalline metallosilicates, such as aluminosilicates, and are composed of repeating tetrahedral units of TO4, for example, where T can be Si, Al, or P (or a combination of tetrahedral units). These units are linked together to form a framework with regular intracrystalline cavities and / or molecular-sized channels, such as micropores.

[0009] Embodiments of this disclosure provide that the zeolite catalyst is a synthetic zeolite catalyst. Synthetic zeolite catalysts can be produced, for example, by known processes of crystallization of silica-alumina gel in the presence of alkali and a template. Examples include zeolite beta catalyst (BEA), Linde type A (LTA), Linde types X and Y (Al-rich and Si-rich FAU), Silicalite-1, ZSM-5 (MFI), Linde type B (zeolite P), Linde type F (EDI), Linde type L (LTL), Linde type W (MER), and SSZ-32 (MTT), which are described using IUPAC codes in accordance with the nomenclature of the Structural Committee of the International Zeolite Association. Unless otherwise specified, the IUPAC codes describing the crystal structures depicted by the Structural Committee of the International Zeolite Association refer to the current notation as of the priority date of this document.

[0010] One or more embodiments provide a zeolite catalyst, a zeolite beta (BEA) catalyst. One or more embodiments provide that the zeolite catalyst includes many Brønsted acid moieties, i.e., proton-donating moieties.

[0011] Zeolite catalysts can have SiO2 / Al2O3 molar ratios ranging from 5:1 to 1500:1, as measured using neutron activation analysis. This includes all individual values ​​and subranges of 5:1 to 1500:1. For example, zeolite catalysts can have SiO2 / Al2O3 molar ratios ranging from lower limits of 5:1, 10:1, 15:1, or 20:1 to upper limits of 1500:1, 750:1, 300:1, or 100:1.

[0012] Zeolite catalysts can have an average pore diameter of 5 to 12 angstroms. This includes all individual values ​​and subranges within the 5 to 12 angstrom range; for example, a zeolite catalyst can have an average pore diameter ranging from a lower limit of 5 or 7 angstroms to an upper limit of 11 or 12 angstroms.

[0013] Zeolite catalysts are 130-1000m 2It can have a surface area of ​​130-1000 m². 2 This includes all individual values ​​and subranges of / g, for example, zeolite catalysts have lower limits of 130, 150, 175, 300, 400 or 500m 2 / g ~ Upper limit 1000, 900, or 800m 2 It can have a surface area of ​​ / g. The surface area is measured according to ASTM D4365-19.

[0014] As mentioned above, zeolite catalysts can be produced by processes that utilize templates, sometimes also called organic templates. Templates are sometimes also called template agents and / or structure-directing agents (SDAs). Templates can be added to a reaction mixture for producing a zeolite catalyst to, for example, induce, or direct, the molecular shape and / or pattern of the zeolite catalyst's skeleton. Upon completion of the zeolite catalyst production process, the zeolite catalyst contains templates, for example, templates located in the micropores of the zeolite catalyst. These templates are utilized in the formation of the zeolite catalyst. One or more embodiments provide that the template contains ammonium ions. Zeolite catalysts containing templates can be produced by known processes. Zeolite catalysts containing templates are commercially available. Suitable examples of commercially available metallosilicate catalysts include CP814E, CP814C, CP811C-300, CBV712, CBV720, CBV760, CBV2314, and CBV10A from ZEOLYST INTERNATIONAL (trademark) of Conshohocken, PA.

[0015] Various templates are known that can be used to produce zeolite catalysts. Examples of templates include, among others, tetraethylammonium hydroxide, N,N,N-trimethyl-1-adamante-ammonium hydroxide, hexamethyleneimine, and dibenzylmethylammonium.

[0016] Embodiments of this disclosure provide silica-modified zeolite catalysts by modifying a zeolite catalyst with silica. The modification of the zeolite catalyst can be carried out, for example, through many known processes such as impregnation or solution processes, followed by calcination. Modification of the zeolite catalyst with silica can utilize known conditions, known apparatus, and known components. For example, the zeolite catalyst can be contacted with an organic solvent and / or aqueous solution containing a silicon compound. Examples of organic solvents include, but are not limited to, hexane, toluene, and combinations thereof. Examples of silicon compounds include, but are not limited to, tetramethyl orthosilicate, tetraethyl orthosilicate, and combinations thereof. By modifying the zeolite catalyst, it is provided that the zeolite catalyst is filled with silica from a silicon compound.

[0017] Modifying a zeolite catalyst with silica may involve contacting the zeolite catalyst with a solution containing a silicon compound, followed by calcination. The solution may contain water and / or an organic solvent. Different amounts of silicon compound and / or water and / or organic solvents can be used for different applications.

[0018] Zeolite catalysts can be contacted with solutions containing silica compounds at temperatures ranging from 5°C to 90°C, for example. This includes all individual values ​​and subranges of 5°C to 90°C; for example, zeolite catalysts can be contacted with solutions containing silica compounds at temperatures ranging from a lower limit of 5, 10, or 15°C to an upper limit of 90, 85, or 80°C.

[0019] Zeolite catalysts can be contacted with a solution containing a silica compound for, for example, 0.5 to 96 hours. This includes all individual values ​​and subranges of 0.5 to 96 hours; for example, zeolite catalysts can be contacted with a solution containing a silica compound for a lower limit of 0.5, 0.8, or 1 hour to an upper limit of 96, 72, 48, 24, or 12 hours.

[0020] One or more embodiments of the present disclosure provide that, as considered, many steps of modifying the zeolite catalyst can be repeated. For example, the zeolite catalyst can be brought into contact with a solution containing a silica compound multiple times. When the steps of modifying the zeolite catalyst are repeated, the next step can utilize the same conditions and / or components as the previous step. When the steps of modifying the zeolite catalyst are repeated, the next step can utilize different conditions and / or components than the previous step.

[0021] Silica-modified zeolite catalysts have a silica content of 15–50 weight percent, based on the total weight of the silica-modified zeolite catalyst. In other words, silica is added to the silica-modified zeolite catalyst by modifying the zeolite catalyst with a silicon compound and then calcining it. All individual values ​​and subranges of 15–50 weight percent are included; for example, a zeolite catalyst can have a silica content of 15, 20, 20.5, 21 or 21.5 weight percent to 50, 45, 40, 39 or 38 weight percent, based on the total weight of the silica-modified zeolite catalyst. The silica content is determined by known processes. The silica content is calculated based on the components used to produce the silica-modified zeolite catalyst. For example, the silicon and aluminum content of a silica-modified zeolite beta catalyst is determined by elemental analysis (neutron activation analysis), and the silica content of the silica-modified zeolite catalyst is then calculated using the known amount of aluminum in the zeolite catalyst, based on the structure of the zeolite catalyst, for example.

[0022] One or more embodiments of the present disclosure provide that a silica-modified zeolite catalyst can be provided by contacting a zeolite catalyst with a silicon compound and then calcining the zeolite catalyst. The zeolite catalyst can be calcined at temperatures of 350°C to 700°C to provide a silica-modified zeolite catalyst. This includes all individual values ​​and subranges of 350°C to 700°C, for example, the zeolite catalyst may be calcined at a lower limit of 350°C, 400°C or 450°C to an upper limit of 700°C, 650°C or 600°C.

[0023] Zeolite catalysts can be calcined in many known calcination environments. For example, zeolite catalysts can be calcined in an air environment.

[0024] Zeolite catalysts can be calcined, that is, in a calcination environment, they can be exposed to a temperature of 350°C to 700°C for 1 hour to 24 hours. All individual values and sub-ranges of 1 hour to 24 hours are included. For example, zeolite catalysts can be calcined at a lower limit of 1 hour, 3 hours or 6 hours to an upper limit of 24 hours, 18 hours or 12 hours.

[0025] One or more embodiments provide that the methods disclosed herein include reducing, for example removing, the template of the zeolite catalyst before modifying the zeolite catalyst with silica as contemplated herein. Embodiments of the present disclosure provide that the template of the zeolite catalyst can be reduced by calcination.

[0026] To reduce the template, the zeolite catalyst can be calcined at a temperature of 550°C to 750°C. All individual values and sub-ranges of 550°C to 750°C are included. For example, the zeolite catalyst can be calcined at a lower limit of 550°C, 560°C or 575°C to an upper limit of 750°C, 700°C or 650°C to reduce the template.

[0027] To reduce the template, the zeolite catalyst can be calcined in many known calcination environments. For example, zeolite catalysts can be calcined in an air environment.

[0028] To reduce the template, the zeolite catalyst can be calcined, that is, in a calcination environment, it can be exposed to a temperature of 550°C to 750°C for 1 hour to 24 hours. All individual values and sub-ranges of 1 hour to 24 hours are included. For example, the zeolite catalyst can be calcined at a lower limit of 1 hour, 3 hours or 6 hours to an upper limit of 24 hours, 18 hours or 12 hours.

[0029] Embodiments of this disclosure relate to methods for etherification. Etherification refers to a chemical process, such as a chemical reaction, that produces an ether. Methods disclosed herein include producing a monoalkyl ether by contacting a silica-modified zeolite catalyst with an olefin and an alcohol.

[0030] As used herein, “olefin” refers to a compound that is a hydrocarbon having one or more carbon-carbon double bonds. Embodiments of this disclosure provide that olefins contain 6 to 30 carbon atoms. All individual values ​​and subranges of 6 to 30 carbon atoms are included, for example, an olefin may have a lower limit of 6, 8 or 10 carbon atoms to an upper limit of 30, 20 or 14 carbon atoms.

[0031] Examples of olefins include alpha(α)olefins, internally disubstituted olefins, or cyclic structures (e.g., C3-C 12 Alkenes such as cycloalkenes may be examples. Alpha-olefins contain an unsaturated bond at the α-position of the olefin. Preferred α-olefins may be selected from the group consisting of propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-icosene, 1-docosene, and combinations thereof. Internally disubstituted olefins contain an unsaturated bond that is not at the terminal position of the olefin. Internal olefins may be selected from the group consisting of 2-butene, 2-pentene, 2-hexene, 3-hexene, 2-heptene, 3-heptene, 2-octene, 3-octene, 4-octene, 2-nonene, 3-nonene, 4-nonene, 2-decene, 3-decene, 4-decene, 5-decene, and combinations thereof. Other exemplary olefins may include butadiene and styrene.

[0032] Suitable examples of commercially available olefins include NEODENE® 6-XHP, NEODENE® 8, NEODENE® 10, NEODENE® 12, NEODENE® 14, NEODENE® 16, NEODENE® 1214, NEODENE® 1416, and NEODENE® 16148 from Shell, The Hague, Netherlands.

[0033] Embodiments of the present disclosure provide that an alcohol may contain a single hydroxyl group, two hydroxyl groups, i.e., a glycol, or three hydroxyl groups. The alcohol may contain one or more carbon atoms, or two or more carbon atoms, or three or more carbon atoms, or four or more carbon atoms, or five or more carbon atoms, or six or more carbon atoms, or seven or more carbon atoms, or eight or more carbon atoms, or nine or more carbon atoms, but at the same time may contain 10 or fewer carbon atoms, or nine or fewer carbon atoms, or eight or fewer carbon atoms, or seven or fewer carbon atoms, or six or fewer carbon atoms, or five or fewer carbon atoms, or four or fewer carbon atoms, or three or fewer carbon atoms, or two or fewer carbon atoms. The alcohol may be selected from the group consisting of methanol, ethanol, monoethylene glycol, diethylene glycol, propylene glycol, triethylene glycol, polyethylene glycol, monopropylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, 1,3-propanediol, 1,2-butanediol, 2,3-butanediol, 1,4-butanediol, 1,6-hexanediol, 1,4-cyclohexanemethanediol, glycerol, and combinations thereof. One or more embodiments provide that the alcohol is selected from the group consisting of monoethylene glycol, diethylene glycol, glycerol, and combinations thereof. One or more embodiments provide that the alcohol is a (poly)alkylene glycol such as monoethylene glycol, diethylene glycol, propylene glycol, or triethylene glycol. Examples of (poly)alkylene glycols include monoethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, monopropylene glycol, dipropylene glycol, tripylene glycol, polypropylene glycol, 1,3-propanediol, 1,2-butanediol, 2,3-butanediol, 1,4-butanediol, 1,6-hexanediol, paraxylene glycol, glycerol, and 1,4-cyclohexanemethanediol. One or more embodiments provide that the (poly)alkylene glycol is monoethylene glycol.

[0034] Embodiments of the present disclosure provide a reaction in which an alcohol and an olefin are reacted, for example, in a molar ratio of alcohol to olefin ranging from 0.05:1 to 20:1, in contact with a silica-modified zeolite catalyst. This includes all individual values ​​and subranges of 0.05:1 to 20:1, for example, the alcohol and olefin can be reacted in molar ratios of alcohol ranging from a lower limit of 0.05:1, 0.075:1, or 0.1:1 to an upper limit of 20:1, 18:1, or 15:1 relative to the molar ratio of olefin.

[0035] As described above, the methods disclosed herein include contacting a silica-modified zeolite catalyst with an olefin and an alcohol to produce a monoalkyl ether. The olefin and alcohol can be contacted with the silica-modified zeolite catalyst under known etherification conditions, and known reactors and known reactants can be utilized. For example, the olefin and alcohol can be contacted with a decreasing template zeolite catalyst in a slurry reactor, a fixed-bed reactor, or a fluidized-bed reactor. The reactor can operate in batch mode or continuous mode.

[0036] Silica-modified zeolite catalysts can be used in amounts such as 1% to 50% by weight, based on the total weight of the olefin. This includes all individual values ​​and subranges of 1% to 50% by weight, for example, the silica-modified zeolite catalyst may be at a lower limit of 1%, 3% or 5% by weight and an upper limit of 50%, 40% or 30% by weight, based on the total weight of the olefin.

[0037] Olefins and alcohols can be contacted with silica-modified zeolite catalysts at reaction temperatures ranging from 80°C to 200°C. This includes all individual values ​​and subranges within the 80°C to 200°C range; for example, olefins and alcohols can be contacted with silica-modified zeolite catalysts at lower limits of 80°C, 90°C, or 100°C to upper limits of 200°C, 175°C, or 150°C.

[0038] Reaction pressure can vary depending on the application. For example, reaction pressure can be reduced pressure, atmospheric pressure, or high pressure.

[0039] When a silica-modified zeolite catalyst is contacted with an olefin and an alcohol, a monoalkyl ether is produced. Various monoalkyl ethers can be produced for different applications, for example, by changing which olefin is used and / or which alcohol is used. Advantageously, the etherification method disclosed herein can provide improved, i.e., higher monoalkyl ether selectivity compared to etherification without the use of a silica-modified zeolite catalyst, as described herein.

[0040] Furthermore, the etherification methods disclosed herein can provide improved, i.e., less dialkyl ether selectivity compared to etherification without silica-modified zeolite catalysts, as described herein. [Examples]

[0041] In this embodiment, various terms and names relating to materials are used, including, for example, the following:

[0042] Zeolite beta catalyst (CP 814E, CAS number 1318-02-1, SiO2 / Al2O3 molar ratio of 25:1, average pore size 6.7 angstroms, surface area 680 m²) 2 / g, all organic templates are removed by the commercial supplier before receipt (obtained from Zeolyst International), Zeolite beta catalyst (CP 806EL, CAS number 1318-02-1, SiO2 / Al2O3 molar ratio of 25:1, average pore size in angstroms, surface area 177 m²) 2 ( / g, including the obtained organic template, obtained from Zeolyst International)

[0043] Example 1 was carried out as follows. The zeolite beta catalyst was modified with silica as follows. The zeolite beta catalyst (CP 806EL, 60 grams) was added to hexane (800 mL) in a container (1 L). Tetraethyl orthosilicate (40 mL) was added to the contents of the container while stirring, and then the contents of the container were stirred for 96 hours under ambient conditions. Then, the solvent was removed by rotary evaporation, and the dried zeolite beta catalyst was calcined at 550 °C for 8 hours in an air environment. Next, the obtained material was added to hexane (800 mL) in a container (1 L). Tetraethyl orthosilicate (40 mL) was added to the contents of the container while stirring, and then the contents of the container were stirred for 24 hours under ambient conditions. Then, the solvent was removed by rotary evaporation, and the dried zeolite beta catalyst was calcined at 550 °C for 8 hours in an air environment to obtain a silica-modified zeolite beta catalyst. The silicon and aluminum loadings of the silica-modified zeolite beta catalyst were determined by elemental analysis (neutron activation analysis), and the silica-modified zeolite beta catalyst had an additional silica loading of 37.5% based on the total weight of the silica-modified zeolite beta catalyst.

[0044] Etherification was carried out as follows. The silica-modified zeolite beta catalyst (0.75 grams) was added to a vial reactor (40 mL) equipped with a rare earth magnetic stirring bar (part number: VP 772FN-13-13-150, V&P Scientific, Inc.), 1-dodecene (6.2 grams) and monoethylene glycol (6.7 grams) were added to the vial reactor, the contents of the vial reactor were heated to 150 °C, and stirred for 3 hours for etherification. Then, the contents of the vial reactor were analyzed by gas chromatography. The gas chromatography sample was prepared by adding the contents of the vial reactor (100 μL) to 10 mL of an internal standard solution (1 mL of hexadecane dissolved in 1 L of ethyl acetate), and then analyzed offline using an Agilent GC (7890). For the analysis, dioxane, 1-dodecene (1-C 12 ) and its isomers (C 12), 2-dodecanol, diethylene glycol, monoalkyl ethers and their isomers, as well as dialkyl ethers and their isomers, were included for product quantification so that a certain weight percentage of interest could be obtained.

[0045] The species derived from dodecene were dodecyl-monoether (ME), dodecyl-diether (DE), and 2-dodakanol.

[0046] The total amount of dodecene includes 1-dodecene and all other C1-dodecenes. 12 It contained isomers.

[0047] Total amount of seeds derived from dodecene = monoethermoles + 2 × diethermoles + 2 - dodecanol.

[0048] Dodecyl monoether (ME) selectivity (%) is expressed as [total amount of ME] / [C 12 It was determined as [total amount of originating species] × 100%.

[0049] Dodecyl-diether (DE) selectivity (%) is expressed as 2 × [total amount of DE] / [C 12 It was determined as [total amount of originating species] × 100%.

[0050] Olefin conversion rate (%), [C 12 [Total amount of species derived from] / [C 12 The formula was determined as [Total amount of originating species + Total amount of Dodesen] × 100%.

[0051] The results are reported in Table 1.

[0052] Comparative Example A was carried out in the same manner as Example 1, with modifications including not modifying the zeolite beta catalyst (CP 806EL) with silica, using 0.35 grams of catalyst instead of 0.75 grams, and shortening the etherification reaction time from 3 hours to 1.5 hours. The catalyst loading amount and / or etherification reaction time were adjusted so that Example 1 and Comparative Example A had similar olefin conversion rates. The results are reported in Table 1. [Table 1]

[0053] The data in Table 1 shows that Example 1 exhibited improved, i.e., greater monoalkyl ether selectivity compared to Comparative Example A.

[0054] The data in Table 1 shows that Example 1 was improved compared to Comparative Example A, i.e., it had less dialkyl ether selectivity.

[0055] Example 2 was carried out as follows. Zeolite beta catalyst (CP 814E) was calcined in an air environment at 550°C for 12 hours to convert the catalyst from NH4 type to H type, and then the catalyst was modified with silica as follows. Zeolite beta catalyst (41 grams) was impregnated with a solution containing hexane (80 mL) and tetraethyl orthosilicate (20 mL), and the components were stirred at 20°C for 5 minutes. The catalyst was then dried in a box oven at 200°C for 1 hour. The catalyst was then calcined in an air environment at 550°C for 4 hours to obtain silica-modified zeolite beta catalyst.

[0056] Etherification was carried out as follows: A silica-modified zeolite beta catalyst (0.75 g) was added to a vial reactor (40 mL) equipped with a rare-earth magnetic stirring rod (part number: VP 772FN-13-13-150, V&P Scientific, Inc.). 1-dodecene (6.2 g) and monoethylene glycol (6.7 g) were then added to the vial reactor, and the contents of the vial reactor were heated to 150°C and stirred for 3 hours for etherification. The results are reported in Table 2.

[0057] Comparative Example B was carried out in the same manner as Example 2, but without modifying the zeolite beta catalyst (CP 814E) with silica. The results are reported in Table 2. [Table 2]

[0058] The data in Table 2 shows that Example 2 exhibited improved, i.e., greater monoalkyl ether selectivity compared to Comparative Example B.

[0059] The data in Table 2 shows that Example 1 was improved compared to Comparative Example B, i.e., it had less dialkyl ether selectivity.

[0060] Example 3 was carried out as follows. Zeolite beta catalyst (CP 814E) was calcined in an air environment at 550°C for 12 hours to convert the catalyst from NH4 type to H type, and then the catalyst was modified with silica as follows. Zeolite beta catalyst (10 grams) and hexane (100 mL) were added to a container, and then tetraethyl orthosilicate (16.5 grams) was added to the container, and the contents of the container were stirred at 20°C for 60 hours. The contents of the container were then centrifuged to obtain a solid, which was calcined in an air environment at 550°C for 8 hours to obtain silica-modified zeolite beta catalyst.

[0061] Etherification was carried out as follows: A silica-modified zeolite beta catalyst (0.75 g) was added to a vial reactor (40 mL) equipped with a rare-earth magnetic stirring rod (part number: VP 772FN-13-13-150, V&P Scientific, Inc.). 1-dodecene (6.2 g) and monoethylene glycol (6.7 g) were then added to the vial reactor, and the contents of the vial reactor were heated to 150°C and stirred for 1 hour for etherification. The results are reported in Table 3.

[0062] Comparative Example C was carried out in the same manner as Example 3, with the following modifications: the zeolite beta catalyst (CP 814E) was not modified with silica, 0.35 grams of catalyst were used instead of 0.75 grams, and the etherification reaction was performed for 1 hour. The catalyst loading amount was adjusted so that Example 3 and Comparative Example C had similar olefin conversion rates (%). The results are reported in Table 3. [Table 3]

[0063] The data in Table 3 shows that Example 3 exhibited improved, i.e., greater monoalkyl ether selectivity compared to Comparative Example C.

[0064] The data in Table 3 shows that Example 3 was improved compared to Comparative Example C, i.e., it had less dialkyl ether selectivity.

Claims

1. A step of removing the template of the zeolite catalyst before modification, which includes calcining the zeolite catalyst, The process includes modifying a zeolite catalyst by impregnating it with a solution containing a silicon compound such that the amount of silica filling is 15 to 50 weight percent based on the total weight of the silica-modified zeolite catalyst. The zeolite catalyst is a zeolite beta catalyst, The silicon compound is tetramethyl orthosilicate or tetraethyl orthosilicate. The process of preparing a silica-modified zeolite catalyst, The process includes a step of producing a monoalkyl ether by contacting a silica-modified zeolite catalyst with an olefin and an alcohol having two or more hydroxyl groups. The alcohol is selected from the group consisting of monoethylene glycol, diethylene glycol, glycerol, and combinations thereof. Methods of etherification.

2. The method according to claim 1, wherein the olefin comprises 6 to 30 carbon atoms.

3. The aforementioned olefin is C １２ -C １４ The method according to claim 1, wherein the material is an olefin.

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