CN107107042A

CN107107042A - Prepare catalyst of glycol ether and its preparation method and application

Info

Publication number: CN107107042A
Application number: CN201580059141.3A
Authority: CN
Inventors: 袁兴东; 京堂真大; 山下雅由; 李永烨
Original assignee: Highchem Technology Co ltd
Current assignee: Highchem Co Ltd
Priority date: 2015-05-25
Filing date: 2015-05-25
Publication date: 2017-08-29
Anticipated expiration: 2035-05-25
Also published as: WO2016187773A1; CN107107042B

Abstract

Present invention offer is a kind of to prepare catalyst of glycol ether and preparation method thereof, wherein with the gross weight meter of the catalyst, the catalyst includes following components：A) 30 85 weight % silica alumina ratio (SiO₂/Al₂O₃) be 50 350 zeolite molecular sieve, wherein the pore size of zeolite molecular sieve be 3 10 angstroms；B) 0.01 5 weight % metal oxide modifier, wherein one or more of the metal in Group IIA metal, La, Ga and Cu；And c) 15 65 weight % binding agent, and the summation of each component always added up as 100 weight %.The catalyst is particularly suitable for use in and prepares glycol ether and selectivity cheap, with higher ethylene glycol reforming rate and glycol ether by lower alkyl alcohol and/or lower alkyl ether and ethylene glycol and/or ethylene glycol mono-ether.The present invention also provides a kind of method using catalyst preparation glycol ether of the present invention.

Description

Catalyst for preparing glycol ether and preparation method and application thereof

Technical Field

The invention relates to a catalyst for preparing glycol ether, a preparation method and application thereof.

Background

Glycol ethers include ethylene glycol monoethers, ethylene glycol diethers, and polyethylene glycol monoethers and polyethylene glycol diethers, which are typically represented by ethylene glycol monomethyl ether (MMET) and ethylene glycol dimethyl ether (DMET). Since glycol ether molecules contain both hydroxyl and ether groups and are miscible with a variety of organic compounds, it is not only a good solvent, but also an intermediate in many organic syntheses. Glycol ethers have also developed in recent years for new applications, such as for extraction of drugs, as liquid crystal orientation agents, etc. Glycol ethers, especially glycol dimethyl ether, have better stability and higher cetane number, and can also be used as diesel additives for reducing the emission of carbon smoke. Therefore, the research on the synthesis and application of glycol ether is a very significant topic.

At present, the following methods are mainly used for synthesizing glycol ether:

(1) the current commercial process is the Williamson phase transfer process. The method uses ethylene glycol or ethylene glycol monoether as raw material, chloromethane as methylation reagent, crown ether or quaternary ammonium salt as phase transfer catalyst, and obtains the ethylene glycol diether. This process has the disadvantages that the catalyst is expensive and cannot be recovered, and that it generates hydrogen and salts and is hazardous.

(2) Ethylene oxide process. The method adopts the reaction of ethylene oxide and methanol at high temperature and high pressure, and can use some solid acidic substances as catalysts or does not need the catalysts. CN 101190876A discloses a method for preparing glycol ether, which uses ethylene oxide and low carbon fatty alcohol as raw materials, uses niobium oxide as main active component, uses one or more of elements selected from vanadium, molybdenum, tungsten, tin, lead, lanthanum, praseodymium and neodymium and compounds thereof as auxiliary agent to prepare the glycol ether under the conditions of reaction temperature of 100-300 ℃, reaction pressure of 0.1-3.0MPa, alcohol-alkyl ratio of 1-5 and reaction time of 0.5-8.0h, so as to solve the problems of low selectivity of the target product glycol ether, high alcohol-ethylene oxide molar ratio (alcohol-alkyl ratio) and the like in the prior art. However, this method cannot avoid the formation of a large amount of carbon dioxide as a by-product. And the method has the advantages of complex process and high energy consumption, and is not suitable for industrial production. CN1005133A reports that a ZSM-5 molecular sieve is used as a matrix, and an NKC-01 solid acid catalyst is prepared by exchanging inorganic acid, and glycol ether is prepared from ethylene oxide and low-carbon alcohol in a batch kettle. When the molar ratio of the alcohol to ethylene oxide in the raw material is 5, the catalytic activity is high and the conversion of ethylene oxide is close to 100%, but the selectivity of glycol ethers, particularly glycol dimethyl ether, is low and the reaction cannot proceed when the molar ratio of ethylene oxide to alcohol is low. CN1033742C on the basis of CN1005133A, the acidity of the catalyst is strengthened by a hydrothermal treatment method, and then the catalyst is used for the reaction of ethylene oxide and ethanol. Under the same reaction conditions, the method improves the conversion rate of the ethylene oxide, but does not improve the selectivity of the glycol ether, and a large amount of glycol is generated. Furthermore, the ethylene oxide used in this process is explosive.

(3) An ethylene process. Chinese patent CN102952003A discloses a method for preparing ethylene glycol monomethyl ether directly from ethylene, methanol and hydrogen peroxide as raw materials on a catalyst containing a titanium silicalite molecular sieve. The method has the defects of needing to use hydrogen peroxide as an oxidant, needing to use a toxic solvent, being easy to decompose and having high industrial price.

(4) Ethylene Glycol (EG) and methanol or dimethyl ether are used as raw materials. US2004/0044253 reports a process for the synthesis of glycol ethers from ethylene glycol or ethylene glycol monoethers and lower alcohols on perfluorosulfonic acid resin catalysts using a batch process with a maximum conversion of ethylene glycol of 77.2% and a total ether selectivity of 94.3%. The method has the advantages of wide raw material source and low price, but the method has the biggest problems that the price of the used catalyst, namely perfluorosulfonic acid resin, is very high, the catalyst is easy to deform under the influence of temperature in the using process, the regeneration is difficult, and the industrialization cannot be realized.

In summary, the industrial method of the conventional glycol ether production method is the Williamson phase transfer method, but the method uses highly toxic methyl chloride, which is unfavorable for the operation environment. In addition, the method uses strong base NaOH, so that the method has great corrosion to equipment. In the process using ethylene oxide and a lower alcohol as raw materials, the ethylene oxide used is liable to be explosive. In addition, the selectivity of glycol ether, especially glycol dimethyl ether, in the method is low, and the byproducts of dioxane and glycol are more. Among the above several processes for preparing glycol ethers, the method using ethylene glycol and methanol as raw materials is most economical and environmentally friendly, but it is required to improve the performance of the catalyst.

With the successful industrialization of the process for preparing glycol from coal, glycol is guaranteed to be used as a raw material for producing glycol ether. Based on the current situation that in the prior art, in the technology for preparing glycol ether by using lower alkyl alcohol and/or lower alkyl ether and ethylene glycol and/or ethylene glycol monoether as raw materials, expensive and difficult-to-regenerate perfluorosulfonic acid resin is needed as a catalyst, a solid catalyst which has a low price, can combine a good conversion rate of ethylene glycol and/or ethylene glycol monoether and glycol ether selectivity, and is low in dioxane byproducts is needed to replace a perfluorosulfonic acid resin catalyst so as to realize industrialization of etherification reaction of ethylene glycol and lower alkyl alcohol and/or lower alkyl ether to produce glycol ether.

Disclosure of Invention

In view of the above-mentioned prior art, the present inventors have conducted extensive and intensive studies on a catalyst for producing glycol ethers from lower alkyl alcohols and/or lower alkyl ethers and ethylene glycol and/or ethylene glycol monoethers as raw materials, and have found a catalyst for producing glycol ethers from lower alkyl alcohols and/or lower alkyl ethers and ethylene glycol and/or ethylene glycol monoethers, which overcomes the above-mentioned disadvantages of the prior art, is inexpensive, and has a high conversion rate of ethylene glycol and a high selectivity of glycol ethers.

It is an object of the present invention to provide a catalyst for the preparation of glycol ethers, wherein the catalyst comprises the following components, based on the total weight of the catalyst:

a) silicon to aluminum molar ratio (SiO) of 30-85 wt%₂/Al₂O₃) A zeolite molecular sieve of 50 to 350, wherein the zeolite molecular sieve has a pore size of 3 to 10 angstroms;

b)0.01 to 5 wt% of a metal oxide modifier, wherein the metal is selected from one or more of a group IIA metal, La, Ga and Cu; and

c) 15-65% by weight of a binder, and the sum of the individual components always adds up to 100% by weight.

It is another object of the present invention to provide a process for preparing the catalyst of the present invention, which comprises the steps of:

(1) mixing the mole ratio of silicon to aluminum (SiO)₂/Al₂O₃) Kneading a zeolite molecular sieve of 50-350 with a binder, a forming aid, water and an acid, then forming, drying, roasting, then crushing and sieving to obtain solid particles, wherein the acid is selected from one or more of nitric acid, phosphoric acid, sulfuric acid, formic acid, acetic acid, propionic acid, oxalic acid or citric acid; and

(2) contacting the solid particles obtained in the step (1) with an aqueous solution of water-soluble metal salt, drying and roasting to obtain the catalyst, wherein the metal is one or more selected from IIA group metal, La, Ga and Cu,

wherein the amount of each component is calculated by the total weight of the catalyst, and the catalyst comprises the following components:

It is still another object of the present invention to provide a method for producing glycol ether, comprising: under the condition of etherification, a material a and a material b are contacted with the catalyst provided by the invention, wherein the material a is ethylene glycol and/or ethylene glycol monoether, and the material b is C₁-C₆Alkyl alcohol and/or di-C₁-C₆An alkyl ether.

The catalyst of the invention is especially suitable for preparing glycol ether from lower alkyl alcohol and/or lower alkyl ether and glycol and/or glycol monoether, and has the advantages of low price, high conversion rate of glycol and high selectivity of glycol ether. The method for preparing the glycol ether provided by the invention has higher conversion rate of the glycol and selectivity of the glycol ether.

Drawings

FIG. 1 illustrates the effect of reaction temperature on glycol ether synthesis.

Figure 2 illustrates the stability of the catalyst prepared in example 1.

Figure 3 illustrates the stability of the catalyst prepared in example 1 after regeneration.

FIG. 4 illustrates the NH content of β molecular sieves after different Si/Al ratios and metal modification₃-TPD map.

Detailed Description

According to one aspect of the present invention, there is provided a catalyst for the preparation of glycol ethers, wherein the catalyst comprises the following components, based on the total weight of the catalyst:

Preferably, the catalyst comprises the following components, based on the total weight of the catalyst:

a)35-80 wt.% Si/Al molar ratio (SiO)₂/Al₂O₃) A zeolite molecular sieve of 50 to 350, wherein the zeolite molecular sieve has a pore size of 3 to 10 angstroms;

b)0.1 to 3 wt% of a metal oxide modifier, wherein the metal is selected from one or more of a group IIA metal, La, Ga and Cu; and

c) 20-60% by weight of a binder, and the sum of the individual components always adds up to 100% by weight.

The zeolite molecular sieve used in the present invention is based on zeolite molecular sieves known to those skilled in the art, for example, the zeolite molecular sieve may be one or more of USY, Ferrierite, ZSM-5, ZSM-11, ZSM-23, MCM-22, β and mordenite molecular sieves, preferably one or more of ZSM-5, USY, Ferrierite and β molecular sieves, further preferably β and/or Ferrierite molecular sieves, and especially preferably β molecular sieves.

The source of the zeolite molecular sieve is not particularly required in the invention, and the zeolite molecular sieve can be obtained by commercial products or synthesis of the zeolite molecular sieve by the prior art, such as hydrothermal synthesis.

According to the invention, the zeolitic molecular sieve may have a silica to alumina molar ratio ranging from 50 to 350, but from ethylene glycol and C₁-C₆Alkyl alcohol and/or di-C₁-C₆The conversion rate of raw materials in the process of preparing glycol ether by converting alkyl ether and the selectivity of glycol ether are considered, and the preferred silica-alumina molar ratio of the zeolite molecular sieve is 75-300.

The metal in the metal oxide improver is one or more selected from group IIA metals, La, Ga and Cu. From the viewpoint of selectivity of glycol ether, the metal is preferably one or more of Mg, La, Ca, Ga and Cu, more preferably one or more of Mg, Cu and Ca, and still more preferably Mg and/or Ca.

The type of the binder used in the present invention is not particularly limited, and may be selected according to actual needs. For example, the binder may be clay, alumina sol, pseudo-boehmite, silica sol, or the like, or mixtures thereof. The content of the binder is not particularly limited, and the binder may be charged in a conventional amount.

In a preferred embodiment of the present invention, the catalyst comprises the following components, based on the total weight of the catalyst:

a)35-80 wt.% Si/Al molar ratio (SiO)₂/Al₂O₃) A zeolitic molecular sieve of 75 to 300, wherein the zeolitic molecular sieve has a pore size of 4.5 to 9 angstroms and is selected from one or more of the ZSM-5, USY, Ferrierite and β molecular sieves;

b)0.1 to 3 wt% of a metal oxide modifier, wherein the metal is one or more of Mg, Cu and Ca; and

c) 20-60% by weight of a binder, and the sum of the individual components always adds up to 100% by weight. The catalyst thus obtained is prepared by₁-C₆Alkyl alcohol and/or di-C₁-C₆The selectivity and conversion rate are especially high when alkyl ether reacts with glycol to prepare glycol ether.

According to another aspect of the present invention, there is provided a process for preparing the catalyst of the present invention, the process comprising the steps of:

(1) mixing the mole ratio of silicon to aluminum (SiO)₂/Al₂O₃) Kneading a zeolite molecular sieve of 50 to 350 with a binder, a forming aid, water and an acid, followed by forming, drying, calcining, and then crushing and sieving to obtain solid particles, wherein the acid used comprises one or more of an inorganic acid (such as nitric acid, phosphoric acid, sulfuric acid, and the like) or an organic acid (such as formic acid, acetic acid, propionic acid, oxalic acid, citric acid, and the like); and

a) 30-85% by weight ofSilicon to aluminum molar ratio (SiO)₂/Al₂O₃) A zeolite molecular sieve of 50 to 350, wherein the zeolite molecular sieve has a pore size of 3 to 10 angstroms;

In the present invention, the type of the molding aid in the step (1) is not particularly limited, and may be selected according to actual needs. For example, it may be one or more of sesbania powder, polyvinyl alcohol or polyethylene glycol. The amount of the forming aid is not particularly limited, and the forming aid is added in the conventional catalyst preparation process. For example, the forming aid may be used in an amount of 1 to 20 parts by weight, preferably 3 to 15 parts by weight, more preferably 5 to 10 parts by weight on a dry basis, relative to 100 parts by weight of the catalyst.

In the present invention, the kind of the acid in the step (1) is not particularly limited, and may be selected according to actual needs. For example, it may be one or more of inorganic acids (e.g., nitric acid, phosphoric acid, sulfuric acid, etc.), organic acids (e.g., formic acid, acetic acid, propionic acid, oxalic acid, citric acid, etc.). The amount of the acid is not particularly limited, and the acid may be fed in the conventional catalyst preparation process. For example, the acid may be used in an amount of 1 to 20 parts by weight, preferably 1 to 15 parts by weight, and more preferably 1 to 10 parts by weight on a dry basis, relative to 100 parts by weight of the catalyst.

The invention also has no special limitation on the using amount of water in the step (1), and the water is fed according to the using amount of water in the conventional catalyst preparation process. For example, the water may be used in an amount of 40 to 80 parts by weight, preferably 50 to 70 parts by weight, on a dry basis, relative to 100 parts by weight of the catalyst.

According to the present invention, the kind of the water-soluble metal salt can be selected in a wide range, for example, the water-soluble metal salt can be a water-soluble salt of group IIA metal, La, Ga, Cu or a mixture thereof, specifically can be a nitrate, carbonate, hydrochloride or a mixture thereof of group IIA metal, La, Ga or Cu, preferably a nitrate, carbonate, hydrochloride or a mixture thereof of Mg, Cu or Ca, and more preferably a nitrate, carbonate, hydrochloride or a mixture thereof of Mg and/or Ca.

The present invention does not particularly require the kneading conditions of step (1), and generally, the kneading conditions may include: the kneading temperature is 20-50 ℃, and the kneading time is 20-90 minutes; it is preferable that the kneading temperature is 20 to 30 ℃ and the kneading time is 25 to 45 minutes.

The method of the present invention further comprises the steps of shaping, drying and firing after the kneading in step (1). The molding method, the drying method and the firing method can be performed by methods known in the art. For example, the molding method may be extrusion molding. The drying can be a conventional drying method, such as oven drying, and the drying temperature can be 50-250 ℃, preferably 100-200 ℃; the drying time may be 5 to 96 hours, preferably 5 to 20 hours. Calcination may be the conventional calcination conditions for preparing the H-type zeolite molecular sieve, for example, the calcination temperature may be 500-750 ℃, preferably 500-650 ℃; the calcination time may be 1 to 10 hours, preferably 3 to 8 hours.

The water-soluble metal salt and the formed zeolite molecular sieve in the step (2) of the method can adopt an impregnation method commonly used in the field, and generally, the contact condition can comprise that the contact temperature is 30-90 ℃, and the contact time is 2-15 hours; preferably, the contact temperature is 50-80 ℃ and the contact time is 2-10 hours.

The drying of step (2) may be the conventional drying conditions of the molecular sieve, specifically, the drying temperature may be 50-250 ℃, preferably 100-200 ℃; the drying time may be 4 to 20 hours, preferably 4 to 16 hours.

The roasting of the step (2) can be the conventional roasting condition for preparing the zeolite molecular sieve; for example, the temperature of the calcination can be 500-750 ℃, preferably 500-650 ℃; the calcination time may be 1 to 10 hours, preferably 3 to 8 hours.

In the preparation method of the present invention, the zeolite molecular sieve, the kind of the metal in the water-soluble metal salt, the kind and the amount of the binder, and the preferable conditions are as described above, and will not be described herein again.

According to a further aspect of the present invention there is provided a process for the preparation of glycol ethers using a catalyst according to the present invention, which process comprises: under the etherification condition, a material a and a material b are contacted with the catalyst provided by the invention or the catalyst prepared by the method of the invention, wherein the material a is ethylene glycol and/or ethylene glycol monomethyl ether, and the material b is C₁-C₆Alkyl alcohol and/or di-C₁-C₆An alkyl ether.

According to the present invention, the molar ratio of the material b to the material a is not particularly limited, and for example, the molar ratio of the material b to the material a may be 0.1 to 20: 1, preferably 1 to 10: 1, more preferably 2 to 6: 1.

according to the present invention, the conditions for contacting the feed a and the feed b with the catalyst are not particularly limited, and for example, the contacting conditions may include: the contact temperature is 100-400 ℃, the contact pressure is 0.1-10.0MPa, and the mass space velocity of the total flow meter of the material a and the material b is 0.05-15h^-1. From the viewpoint of reaction conversion rate and glycol ether selectivity, the preferred contact temperature is 180 ℃ to 220 ℃, the contact pressure is 3.5 to 7.0MPa, and the mass space velocity of the total flow meter of the material a and the material b is 1.0 to 10h^-1。

According to the invention, the invention is directed to said C₁-C₆The choice of alkyl alcohol is not particularly limited. Specifically, examples thereof include, but are not limited to: one or more of methanol, ethanol, n-propanol, isopropanol, n-butanol and its isomer, n-pentanol and its isomer, and n-hexanol and its isomer; preferably one or more of methanol, ethanol, n-propanol, n-butanol, n-pentanol and n-hexanol; further preferably one or more of methanol, ethanol, n-propanol and n-butanol.

According to the invention, the invention is applied to said di-C₁-C₆The choice of alkyl ether is not particularly limited. Specifically, examples thereof include, but are not limited to: dimethyl ether, diethyl ether, di-n-propyl ether, diisopropyl ether, di-n-butyl ether and isomers thereof, di-n-pentyl ether and isomers thereofDi-n-hexyl ether and isomers thereof; preferably one or more of dimethyl ether, diethyl ether, di-n-propyl ether, di-n-butyl ether, di-n-pentyl ether and di-n-hexyl ether; further preferred is dimethyl ether.

According to the invention, the source of ethylene glycol includes not only pure ethylene glycol commercial products but also starting products of plants for the industrial production of ethylene glycol. The sources of the ethylene glycol monoethers not only comprise pure ethylene glycol monoethers commodities, but also can be initial products of devices for industrially preparing the ethylene glycol monoethers. Preferably, material a is ethylene glycol.

The form of the reactor for carrying out the contact according to the method for producing glycol ether of the present invention is not particularly limited, and the reactor may be one or a combination of more of a fixed bed reactor, a slurry bed reactor, a batch tank reactor, a fluidized bed reactor, a moving bed reactor and a monolith reactor. In the present invention, the monolith reactor refers to a reactor using a foamed monolith catalyst, and preferably, the reactor is a fixed bed reactor.

Examples

The present invention is described in detail below with reference to examples and comparative examples, but the scope of the present invention is not limited to these examples.

In the following examples, the analysis of each component in the system by gas chromatography and the quantitative determination by the calibration and normalization method were carried out by referring to the prior art, and evaluation indexes such as the conversion of the reactant, the yield of the product, and the selectivity were calculated based on the analysis.

In the present invention, the conversion of Ethylene Glycol (EG) is calculated as follows:

wherein, X_EGAs conversion of ethylene glycol, m^o _{Raw material EG}Is the mass of the ethylene glycol starting material, m_{Product EG}Is the mass of ethylene glycol in the product.

Selectivity of each product:

wherein S_iAs a selectivity for component i, n_iIs the mass of component i in the product.

The pore size of the molecular sieve is measured by a BJH method.

The following examples and comparative examplesIn the examples, the silica sols used were all SiO₂Silica sol in an amount of 40% by weight; the alumina sol is Al₂O₃An aluminum sol in an amount of 10 wt.%.

Example 1

Mixing commercially available Si/Al molar ratio (SiO)₂/Al₂O₃) 100 g of ammonium form β molecular sieve at 300 ℃ was calcined in air at 550 ℃ for 5 hours to give H form β molecular sieve.

Weighing 70g of prepared H-type β molecular sieve, 30g of clay, 5g of sesbania powder and 60g H g of sesbania powder₂O, 5g of concentrated nitric acid was added thereto, kneaded at 25 ℃ for 30 minutes, extruded into a bar with a die having a diameter of 3.0 mm, air-dried, placed in an oven at 120 ℃ for 12 hours, and then calcined in a muffle furnace at 550 ℃ for 5 hours in an air atmosphere. Then crushing and sieving are carried out to obtain solid particles with the particle size of 1 mm.

Weighing 1.05g Ca (NO)₃)₂·4H₂O was dissolved in 100ml of deionized water, 24g of the above-described molded 1mm solid particles were added, the mixture was immersed at 60 ℃ for 6 hours, excess water was evaporated, and the evaporated solid was placed in an oven at 120 ℃ for 12 hours and then calcined in a muffle furnace at 550 ℃ for 5 hours to obtain a CaO-modified catalyst containing 69.3% by weight of β molecular sieve, 1.0% by weight of CaO and 29.7% by weight of clay, based on the weight of the catalyst, other properties of which are shown in Table 1.

Example 2

The experimental conditions of example 1 were repeated, except that molecular sieve H β (SiO)₂/Al₂O₃300 molar ratio) was entirely made of H-type ZSM-5 zeolite (SiO)₂/Al₂O₃The molar ratio is 100). Other properties of the catalyst are shown in table 1.

Example 3

The experimental conditions of example 1 were repeated, except that molecular sieve H β (SiO)₂/Al₂O₃Molar ratio of 300) all by using USY molecular Sieve (SiO)₂/Al₂O₃The molar ratio is 110). Other properties of the catalyst are shown in table 1.

Example 4

The experimental conditions of example 1 were repeated, except that molecular sieve H β (SiO)₂/Al₂O₃Molar ratio of 300) was used all with Ferrierite (SiO)₂/Al₂O₃Molar ratio 100). Other properties of the catalyst are shown in table 1.

Comparative example 1

The experimental conditions of example 1 were repeated, except that the H form β molecular Sieve (SiO) was not used₂/Al₂O₃Molar ratio of 300) was modified with CaO.

Comparative example 2

Weighing 5.0g of purchased perfluorosulfonic acid resin, adding 100.00g of deionized water, then adding 5.0g of hydrochloric acid with the concentration of 35 weight percent, stirring for 30 minutes, then standing for 12 hours, filtering, washing and drying at 120 ℃.

Example 5

The experimental conditions of example 1 were repeated except that an ammonium β molecular sieve having a silica to alumina molar ratio of 150 was used.

Example 6

The experimental conditions of example 1 were repeated except that an ammonium β molecular sieve having a silica to alumina molar ratio of 75 was used.

Example 7

The experimental conditions of example 1 were repeated, except that: with 1.58g Mg (NO)₃)₂·6H₂O instead of 1.05g Ca (NO)₃)₂·4H₂This catalyst comprised 69.3 wt.% β molecular sieve, 1.0 wt.% magnesia, and 29.7 wt.% clay, based on the total weight of the resulting catalyst.

Example 8

The experimental conditions of example 1 were repeated, except that: with 0.90g Cu (NO)₃)₂·6H₂O instead of 1.05g Ca (NO)₃)₂·4H₂This catalyst comprised 69.3 wt.% β molecular sieve, 1.0 wt.% copper oxide, and 29.7 wt.% clay, based on the total weight of the resulting catalyst.

Example 9

The experimental conditions of example 1 were repeated, except that: all the clay is replaced by pseudo-boehmite to obtain a binder Al₂O₃The catalyst comprised 69.3 wt% of β molecular sieve, 1.0 wt% of calcium oxide, and 29.7 wt% of Al, based on the total weight of the resulting catalyst₂O₃。

Example 10

The experimental conditions of example 1 were repeated, except that the clay was entirely replaced with the silica sol to obtain a catalyst having the silica sol as a binder source, the catalyst contained β molecular sieve in an amount of 69.3 wt%, calcium oxide in an amount of 1.0 wt%, and SiO in an amount of 29.7 wt%, based on the total weight of the catalyst₂。

Example 11

The experimental conditions of example 1 were repeated, except that the clay was entirely replaced with an aluminum sol (Nissan chemical industries, Ltd., AS-200) to obtain a catalyst having the aluminum sol AS a binder source, the catalyst contained 69.3% by weight of β molecular sieve, 1.0% by weight of calcium oxide and 29.7% by weight of Al, based on the total weight of the catalyst₂O₃。

Example 12

The experimental conditions of example 1 were repeated, except that the weight of the H form β zeolite during the formation was 80g, the weight of the clay was 20g, and Ca (NO) during the impregnation was used₃)₂·4H₂The weight of O was 3.15 g. the catalyst comprised 77.6 wt% β molecular sieve, 3.0 wt% calcium oxide, and 19.4 wt% clay, based on the total weight of the resulting catalyst.

Example 13

The experimental conditions of example 1 were repeated, except that the weight of the H form β zeolite during the formation process was 50g, the weight of the clay was 50g, and Ca (NO) during the impregnation process was repeated₃)₂·4H₂The weight of O was 0.52 g. the catalyst comprised 49.75 wt.% β molecular sieve, 0.5 wt.% calcium oxide, and 49.75 wt.% clay, based on the total weight of the resulting catalyst.

Example 14

The experimental conditions of example 1 were repeated, except that the weight of the H form β zeolite during the formation process was 40g, the weight of the clay was 60g, and Ca (NO) during the impregnation process₃)₂·4H₂The weight of O was 0.104 g. the catalyst comprised 39.96 wt.% β molecular sieve, 0.1 wt.% calcium oxide, and 59.94 wt.% clay, based on the total weight of the resulting catalyst.

Example 15

This example serves to illustrate the preparation of glycol ethers from ethylene glycol and methanol using the catalyst of the present invention.

In a stainless steel tube reactor with an inner diameter of 6 mm, 2.0g of the formed catalyst prepared in example 1 is filled, methanol and ethylene glycol with a molar ratio of 4.0/1.0 are introduced under 5.0MPa, the reaction temperature is 210 ℃, and the mass space velocity of a total flow meter of the material a and the material b is 1.2h^-1The results are shown in Table 1.

Examples 16 to 28

The experimental conditions of example 15 were repeated except that: the catalysts used were replaced with the catalysts prepared in examples 2 to 14, respectively. The results of the experiment are shown in Table 1.

Comparative examples 3 to 4

The experimental conditions of example 15 were repeated except that: the catalysts used were replaced with the catalysts prepared in comparative examples 1-2, respectively. The results of the experiment are shown in Table 1.

Examples 29 to 32

The same experimental conditions as in example 15 were repeated, except that: the methanol feed was replaced with ethanol, n-propanol, n-butanol and dimethyl ether feed, respectively, and the results are listed in table 2.

Example 33

The experimental conditions of example 15 were repeated except that: the methanol in the feed was replaced with a mixture feed of methanol, ethanol, n-propanol and n-butanol at a molar ratio of 1/1/1/1, and the results are listed in table 2.

Examples 34 to 37

The experimental conditions of example 15 were repeated except that: the molar ratio of methanol to ethylene glycol in the feed was changed to 2/1, 3/1, 5/1, 6/1 feeds and the results are listed in table 2.

Examples 38 to 41

The experimental conditions of example 15 were repeated except that: the reaction temperatures were changed to 180 deg.C, 190 deg.C, 200 deg.C and 220 deg.C, respectively, and the results are shown in FIG. 1.

Examples 42 to 44

The experimental conditions of example 15 were repeated except that: the reaction pressure was changed to 0.1MPa, 3.5MPa and 7.0MPa, respectively. And (3) reaction results: the conversion of ethylene glycol was 67.46%, 72.81% and 74.83%, respectively; the selectivity of the mono-ethylene glycol ether was 10.47%, 58.93% and 99.46%, respectively, the selectivity of the dioxane was 77.59%, 20.04% and 0.05%, respectively, and the selectivity of the poly-ethylene glycol ether was 31.94%, 21.03% and 0.49%, respectively.

Examples 45 to 47

The experimental conditions of example 15 were repeated except that: the mass airspeeds of the total flow meters of the material a and the material b are respectively 1.0h^-1、4.8h^-1And 9.6h^-1And the reaction result; the conversion of ethylene glycol was 89.76%, 46.69% and 25.52%, respectively; the selectivity of the mono-ethylene glycol ether was 89.81%, 99.67% and 99.66%, respectively, the selectivity of dioxane was 7.38%, 0.14% and 0.15%, respectively, and the selectivity of the poly-ethylene glycol ether was 2.81%, 0.18% and 0.19%, respectively.

Example 48

The experimental conditions of example 15 were repeated except that: the reaction time was extended to 2000 hours. The results of the experiment are shown in fig. 2.

Example 49

After the preparation of example 48 was complete, the ethylene glycol and methanol feeds were stopped, the catalyst bed was purged with 50ml/min of nitrogen for 30 minutes, then air was added at a rate of 50ml/min to raise the temperature from 210 ℃ to 550 ℃ at a rate of 8 ℃/min, and then held at 550 ℃ for 8 hours to regenerate the catalyst of example 36. After regeneration, the catalyst bed temperature was reduced to 210 ℃.

The catalyst stability test was carried out using the same test conditions as in example 48, and the test results are shown in FIG. 3.

TABLE 1 results of the reaction of various catalysts to synthesize glycol ethers

Reaction conditions are as follows: the reaction temperature is 210 ℃, the reaction pressure is 5.0MPa, the molar ratio of the material b to the glycol is 4/1, the weight of the catalyst is 2.0g, and the mass space velocity based on the total flow of the material b and the glycol is 1.2h^-1。

TABLE 2 influence of the type and composition of the materials b on the glycol ether synthesis reaction

Reaction conditions are as follows: the reaction temperature is 210 ℃, the reaction pressure is 5.0MPa, the weight of the catalyst is 2.0g, and the mass space velocity based on the total flow of the material b and the glycol is 1.2h^-1。

From the results in tables 1 and 2, several molecular sieve and perfluorosulfonic acid resin catalysts were selected to convert ethylene glycol and methanol into glycol ether, but when USY molecular sieve with large pore size or perfluorosulfonic acid resin was used as the active site of the catalyst, the conversion rate of ethylene glycol was relatively high, but the selectivity of harmful substances dioxane and polyalcohol ether in the product was high, and the USY molecular sieve catalyst was deactivated at a high rate, probably associated with large pore size and more by-products of macromolecules, and easily clogged in the channels. The perfluorosulfonic acid resin catalyst gradually decreases in activity with time, possibly related to the loss of sulfonic acid, and in addition, when the reaction is completed, the perfluorosulfonic acid resin catalyst is found to be severely deformed, indicating that the stability of the catalyst cannot reach the industrial level. When the catalyst containing Ferrierite molecular sieve with the smallest pore diameter is used, the catalyst has the highest ethylene glycol conversion rate of 90.71% and glycol ether selectivity of 100%, but the selectivity of glycol dimethyl ether is low and is only 24.53%, and after the catalyst is used for 120 hours, the conversion rate of ethylene glycol is only 43.73%, and the deactivation is quick; the activity of ZSM-5 molecular sieve catalyst with the same small pore diameter is as high as 77.94%, the selectivity of glycol ether is 98%, but the selectivity of glycol dimethyl ether is only 35.61%, 1.75% of dioxane is generated, the catalyst is also inactivated quickly, the conversion rate of the glycol is reduced to 55.74% after 240 hours, and the product selectivity and stability and the pore diameter of the molecular sieve are relatively smallTo a small scale, β (SiO)₂/Al₂O₃Molar ratio of 300) molecular sieve is used as a catalyst, although the conversion rate of glycol and the selectivity of glycol ether are lower than those of Ferrierite molecular sieve, the Ca is passed through²⁺After modification, the selectivity of glycol ether is up to 98.67%, the selectivity of glycol dimethyl ether is also up to 41.44%, the selectivity of dioxane is below 1.0%, and the stability is the best, which shows that the pore structure of β molecular sieve is favorable for the reaction of synthesizing glycol ether from ethylene glycol and methanol.

NH from molecular sieves₃The TPD graph shows that when the silica-alumina ratio is increased from 75 to 300, the acid strength of β molecular sieve does not change much, the acid density is reduced, the conversion rate of ethylene glycol is only reduced from 84.51% to 75.42%, but the selectivity of the product is obviously changed, wherein the by-product dioxane is reduced from 20.32% to below 0.73%, which indicates that the conversion rate of ethylene glycol is related to the acidity of the molecular sieve, the acid density is high, the ethylene glycol is easy to convert, but the more dioxane is generated by dehydration in the ethylene glycol molecule, the more dioxane is unfavorable for the target product, the acid amount is reduced, the activity is reduced, the conversion rate of ethylene glycol is reduced, the acid strength is increased, the reaction of methanol and ethylene glycol is facilitated, and the selectivity of ethylene glycol ether is high.

β molecular sieve is also subjected to acidity modulation, and from the result after metal modification, alkali metal Mg is added²⁺、Ca²⁺The modification of (A) is better, the selectivity of glycol ether, especially glycol dimethyl ether is improved, the selectivity of by-product dioxane and heavy components is inhibited, and the catalyst is more stable, wherein Ca is used²⁺The modified β molecular sieve catalyst is optimal, the stability of the fresh catalyst is higher than 2000 hours, and the catalyst can be regenerated for many times.

Claims

A catalyst for the preparation of glycol ethers, wherein the catalyst comprises the following components, based on the total weight of the catalyst:

a) silicon to aluminum molar ratio (SiO) of 30-85 wt%₂/Al₂O₃) A zeolite molecular sieve of 50 to 350, wherein the zeolite molecular sieve has a pore size of 3 to 10 angstroms;

b)0.01 to 5 wt% of a metal oxide modifier, wherein the metal is selected from one or more of a group IIA metal, La, Ga and Cu; and

c) 15-65% by weight of a binder, and the sum of the individual components always adds up to 100% by weight.
The catalyst according to claim 1, wherein the catalyst comprises the following components, based on the total weight of the catalyst:

a)35-80 wt.% Si/Al molar ratio (SiO)₂/Al₂O₃) A zeolite molecular sieve of 50 to 350, wherein the zeolite molecular sieve has a pore size of 3 to 10 angstroms;

b)0.1 to 3 wt% of a metal oxide modifier, wherein the metal is selected from one or more of a group IIA metal, La, Ga and Cu; and

c) 20-60% by weight of a binder, and the sum of the individual components always adds up to 100% by weight.
The catalyst of claim 1 or 2, wherein the molar ratio of silicon to aluminum (SiO)₂/Al₂O₃) Is 75-300.
The catalyst according to any one of claims 1-3, wherein the zeolitic molecular sieve is one or more of USY, Ferrierite, ZSM-5, ZSM-11, ZSM-23, MCM-22, β, and mordenite molecular sieves, preferably one or more of ZSM-5, USY, Ferrierite, and β molecular sieves, further preferably β and/or Ferrierite molecular sieves, especially preferably β molecular sieves.
The catalyst according to any of claims 1 to 4, wherein the metal is one or more of Mg, Ga, La, Ca and Cu, preferably one or more of Mg, Cu and Ca, further preferably Mg and/or Ca.
The catalyst of any one of claims 1 to 5, wherein the binder is one or more of clay, alumina sol, pseudoboehmite, and silica sol.
The catalyst of any of claims 1 to 6 wherein the zeolitic molecular sieve has a pore size of from 4.5 to 9 angstroms.
A process for preparing a catalyst according to any one of claims 1 to 7, the process comprising the steps of:

(1) mixing the mole ratio of silicon to aluminum (SiO)₂/Al₂O₃) Kneading a zeolite molecular sieve of 50-350 with a binder, a forming aid, water and an acid, then forming, drying, roasting, then crushing and sieving to obtain solid particles, wherein the acid is selected from one or more of nitric acid, phosphoric acid, sulfuric acid, formic acid, acetic acid, propionic acid, oxalic acid or citric acid; and

(2) contacting the solid particles obtained in the step (1) with an aqueous solution of water-soluble metal salt, drying and roasting to obtain the catalyst, wherein the metal is one or more selected from IIA group metal, La, Ga and Cu,

wherein the components are used in such amounts that the catalyst comprises the following components, based on the total weight of the catalyst:

a) silicon to aluminum molar ratio (SiO) of 30-85 wt%₂/Al₂O₃) A zeolite molecular sieve of 50 to 350, wherein the zeolite molecular sieve has a pore size of 3 to 10 angstroms;

b)0.01 to 5 wt% of a metal oxide modifier, wherein the metal is selected from one or more of a group IIA metal, La, Ga and Cu; and

c) 15-65% by weight of a binder, and the sum of the individual components always adds up to 100% by weight.
A method according to claim 8, wherein the forming aid is selected from one or more of sesbania powder, polyvinyl alcohol and polyethylene glycol.
The method according to claim 7 or 8, wherein the water-soluble metal salt is a nitrate, carbonate, hydrochloride or a mixture thereof of the metal.
A method of making glycol ethers comprising: contacting feed a and feed b with a catalyst according to any one of claims 1 to 7 or prepared according to the process of any one of claims 8 to 10 under etherification conditions, wherein feed a is ethylene glycol and/or ethylene glycol monomethyl ether and feed b is C₁-C₆Alkyl alcohol and/or di-C₁-C₆An alkyl ether.
The process according to claim 11, wherein the molar ratio of feed a to feed b is from 0.1 to 20: 1, preferably 1 to 10: 1, more preferably 2 to 6: 1.
the process according to claim 11 or 12, wherein the etherification conditions comprise: the contact temperature is 100-400 ℃, the contact pressure is 0.1-10.0MPa, and the mass space velocity of the total flow meter of the material a and the material b is 0.05-15h^-1(ii) a The preferred contact temperature is 180 ℃ and 220 ℃, the contact pressure is 3.5-7.0MPa, and the mass space velocity of the total flow meter of the material a and the material b is 1.0-10h^-1。
The method according to any one of claims 11 to 13, wherein C₁-C₆The alkyl alcohol is one or more of methanol, ethanol, n-propanol, isopropanol, n-butanol and isomers thereof, n-pentanol and isomers thereof, n-hexanol and isomers thereof, preferably one or more of methanol, ethanol, n-propanol, n-butanol, n-pentanol and n-hexanol, and further preferably one or more of methanol, ethanol, n-propanol and n-butanol; di C₁-C₆The alkyl ether is dimethyl ether, diethyl ether, di-n-propyl ether, diisopropyl ether, di-n-butyl ether and isomers thereof, di-n-pentyl ether and isomers thereof, and di-n-hexyl ether and isomers thereof; preferably one or more of dimethyl ether, diethyl ether, di-n-propyl ether, di-n-butyl ether, di-n-pentyl ether and di-n-hexyl ether; further preferred is dimethyl ether.