阅读说明：本技术 一种新铃兰醛的制备方法 (Preparation method of lyral ) 是由 柯诗祺 江承艳 于 2020-04-16 设计创作，主要内容包括：本发明涉及一种新铃兰醛的制备方法。具体地,本发明提供一种新铃兰醛的制备方法,所述的方法包括步骤：在有机溶剂中,在水合催化剂的作用下,柑青醛和水发生水合反应生成新铃兰醛。本发明所述的方法具有高收率、高转化率等优异技术效果,且工艺简单,适合工业化生产。(The invention relates to a preparation method of lyral. Specifically, the invention provides a preparation method of lyral, which comprises the following steps: in an organic solvent, under the action of a hydration catalyst, citral and water undergo a hydration reaction to generate lyral. The method has the excellent technical effects of high yield, high conversion rate and the like, is simple in process, and is suitable for industrial production.)

1. A method for preparing lyral, characterized in that the method comprises the steps of:

(1) in an organic solvent, under the action of a hydration catalyst, citral and water undergo a hydration reaction to generate lyral;

wherein the hydration catalyst comprises a first catalyst and a second catalyst; the first catalyst is a solid acid catalyst, the solid acid catalyst comprises a solid acid and a first metal active component, the first metal active component is loaded on the solid acid, and the first metal active component is selected from the following group: platinum, nickel, or a combination thereof;

the second catalyst is modified cation exchange resin loaded with a second metal active component, the modified cation exchange resin is cation exchange resin soaked by strong acid, and the second metal active component is selected from the following group: zinc chloride, aluminum chloride, tin chloride, ruthenium chloride, rhodium chloride, or combinations thereof.

2. The method of claim 1, wherein in step (1), the organic solvent is selected from the group consisting of: isopropanol, tetrahydrofuran, acetone, methyltetrahydrofuran, dioxane, acetic acid, acetate, or combinations thereof.

3. The method of claim 1, wherein in step (1), the hydration catalyst is used in an amount of 0.5 to 10 wt%, preferably 0.5 to 8 wt%, more preferably 1 to 5 wt%, most preferably 1 to 3 wt% of the amount of the myrac aldehyde.

4. The method of claim 1, wherein the solid acid catalyst is prepared by a process comprising the steps of:

impregnating a solid acid with a solution of a material selected from the group consisting of: dipping chloroplatinic acid, nickel nitrate hexahydrate or a combination thereof, drying, and roasting to obtain a solid acid catalyst;

the solid acid is selected from the following group: zeolite, silica, alumina, or combinations thereof.

5. The process of claim 1, wherein the weight percent of platinum based on the solid acid catalyst is from 0.1 to 2.5 wt.%, preferably from 0.1 to 2 wt.%, more preferably from 0.1 to 1.5 wt.%, more preferably from 0.2 to 0.8 wt.%, and most preferably from 0.3 to 0.7 wt.%; and/or

The weight percentage of nickel in the solid acid catalyst is 0.05-1.5 wt%, preferably 0.08-1.0 wt%, more preferably 0.08-0.5 wt%, and most preferably 0.1-0.3 wt%.

6. The process of claim 1 wherein said second metal active component comprises from 0.5 to 20 wt%, preferably from 1 to 15 wt%, more preferably from 2 to 12 wt%, most preferably from 4 to 10 wt%, more preferably from 4 to 8 wt% of said modified cation exchange resin in said second catalyst.

7. The method of claim 1, wherein the method comprises one or more features selected from the group consisting of:

in the second catalyst, the zinc chloride accounts for 0.5-20 wt%, preferably 1-15 wt%, more preferably 2-12 wt%, most preferably 4-10 wt%, more preferably 4-8 wt% of the modified cation exchange resin;

in the second catalyst, the aluminum chloride accounts for 0.5-20 wt%, preferably 1-15 wt%, more preferably 2-12 wt%, most preferably 4-10 wt%, more preferably 4-8 wt% of the modified cation exchange resin;

in the second catalyst, the weight percentage of the tin chloride in the modified cation exchange resin is 0.5-20 wt%, preferably 1-15 wt%, more preferably 2-12 wt%, most preferably 4-10 wt%, more preferably 4-8 wt%; and/or

In the second catalyst, the ruthenium chloride accounts for 0.5-20 wt%, preferably 1-15 wt%, more preferably 2-12 wt%, most preferably 4-10 wt%, and most preferably 4-8 wt% of the modified cation exchange resin.

8. The process of claim 1, wherein the weight ratio of the first catalyst to the second catalyst is from 0.5 to 5:1, preferably 0.5-4:1, more preferably 1-2:1, more preferably 1.2-2:1, more preferably 1.3-1.8: 1.

9. The method of claim 1, wherein the second catalyst is prepared by:

(a) providing a cation exchange resin and a second metal active component;

(b) soaking cation exchange resin in strong acid to obtain modified cation exchange resin;

(c) and mixing the modified cation exchange resin and the second metal active component in an anhydrous solvent, reacting, and filtering to obtain the second catalyst.

10. A hydration catalyst, the hydration catalyst comprising a first catalyst and a second catalyst; the first catalyst is a solid acid catalyst, the solid acid catalyst comprises a solid acid and a first metal active component, the first metal active component is loaded on the solid acid, and the first metal active component is selected from the following group: platinum, nickel, or a combination thereof;

the second catalyst is modified cation exchange resin loaded with a second metal active component, the modified cation exchange resin is cation exchange resin soaked by strong acid, and the second metal active component is selected from the following group: zinc chloride, aluminum chloride, tin chloride, ruthenium chloride, rhodium chloride, or combinations thereof.

Technical Field

The invention relates to the technical field of perfume synthesis, and particularly relates to a preparation method of lyral.

Background

The chemical formula of the lyral is C₁₃H₂₂O₂The trade name is: lyre, a colorless transparent liquid, stable in chemical properties, small in volatility, andhas good color and luster and is not easy to change color. The chemical name of the lyral is 4-or 3- (4-methyl-4-hydroxypentyl) -3-cyclohexene aldehyde, which is a mixture of two isomers and has pleasant fragrance of clove and lily, wherein the fragrance is better in 4-position isomer. The lily and lily flower fragrance essence has lasting lily and conyza blinii flower fragrance, is mild and stable in fragrance, has rich aftertaste, has soft flower fragrance similar to that of hydroxycitronellal, and has stronger taste.

With the increase of the market demand of lyral, a plurality of large perfume companies develop and produce lyral internationally. Due to the irreplaceable role of neocarl in perfume formulations, it is becoming more and more appreciated. It has gradually replaced the traditional synthetic lily of the valley aldehyde in various essences such as perfume essence and the like. However, lyral does not occur in nature, so it needs to be prepared by chemical synthesis. Among them, the international perfume company and the high sand international company have introduced lyral which is the most mature, and the Shanghai perfume research institute of the original Ministry of light industry of China has also developed related researches.

Disclosure of Invention

The invention aims to provide a preparation method of lyral with high yield, high conversion rate, simple process and easy industrial production

In a first aspect of the present invention, there is provided a process for preparing lyral, said process comprising the steps of:

(1) in an organic solvent, under the action of a hydration catalyst, citral and water undergo a hydration reaction to generate lyral;

wherein the hydration catalyst comprises a first catalyst and a second catalyst; the first catalyst is a solid acid catalyst, the solid acid catalyst comprises a solid acid and a first metal active component, the first metal active component is loaded on the solid acid, and the first metal active component is selected from the following group: platinum, nickel, or a combination thereof;

the second catalyst is modified cation exchange resin loaded with a second metal active component, the modified cation exchange resin is cation exchange resin soaked by strong acid, and the second metal active component is selected from the following group: zinc chloride, aluminum chloride, tin chloride, ruthenium chloride, rhodium chloride, or combinations thereof.

In another preferred embodiment, in the step (1), the organic solvent is selected from the group consisting of: isopropanol, tetrahydrofuran, acetone, methyltetrahydrofuran, dioxane, acetic acid, acetate, or combinations thereof.

In another preferred embodiment, in the step (1), the reaction time is 5-12h, preferably 6-10 h.

In another preferred embodiment, in said step (1), said reaction temperature is 50-100 ℃, preferably 60-90 ℃, more preferably 70-90 ℃, most preferably 75-85 ℃.

In another preferred embodiment, in said step (1), the molar ratio of said myrac aldehyde to said water is 0.3 to 1:1, preferably 0.3 to 0.8:1, more preferably 0.4 to 0.6: 1.

in another preferred embodiment, in the step (1), the molar ratio of the organic solvent to the water is 0.5-1.5:0.5-1.5, preferably 0.8-1.2: 0.8-1.2.

In another preferred embodiment, in the step (1), the hydration catalyst is used in an amount of 0.5 to 10 wt%, preferably 0.5 to 8 wt%, more preferably 1 to 5 wt%, and most preferably 1 to 3 wt% of the amount of the myrac aldehyde.

In another preferred embodiment, the weight percentage of the first metal active component in the solid acid catalyst is 0.5-8 wt%, preferably 1-4 wt%.

In another preferred embodiment, the solid acid catalyst is prepared by a process comprising the steps of:

impregnating a solid acid with a solution of a material selected from the group consisting of: dipping chloroplatinic acid, nickel nitrate hexahydrate or a combination thereof, drying, and roasting to obtain a solid acid catalyst;

the solid acid is selected from the following group: zeolite, silica, alumina, or combinations thereof.

In another preferred embodiment, the solution is an aqueous solution.

In another preferred embodiment, the temperature of drying after impregnation is 100-150 ℃.

In another preferred embodiment, the temperature for the calcination is 400-550 ℃, preferably 450-520 ℃.

In another preferred embodiment, the first metal active component is platinum and nickel.

In another preferred embodiment, the weight percentage of platinum to the solid acid catalyst is 0.1 to 2.5 wt%, preferably 0.1 to 2 wt%, more preferably 0.1 to 1.5 wt%, more preferably 0.2 to 0.8 wt%, most preferably 0.3 to 0.7 wt%.

In another preferred embodiment, the nickel is present in an amount of 0.05 to 1.5 wt%, preferably 0.08 to 1.0 wt%, more preferably 0.08 to 0.5 wt%, and most preferably 0.1 to 0.3 wt% based on the weight of the solid acid catalyst.

In another preferred embodiment, the solid acid is zeolite.

In another preferred embodiment, the zeolite is selected from the group consisting of: natural zeolite, beta zeolite, Y zeolite, MCM-22, ZSM-5, or a combination thereof.

In another preferred embodiment, the SiO of the β zeolite₂/Al₂O₃(molar ratio) is 20 to 100, preferably 20 to 40, more preferably 20 to 30.

In another preferred embodiment, the beta zeolite is Cation Type H.

In another preferred embodiment, the beta zeolite further has one or more characteristics selected from the group consisting of:

SiO₂/Al₂O₃(molar ratio) of 20 to 100, preferably 20 to 40, more preferably 20 to 30;

the crystallinity is more than or equal to 90 percent, preferably 90 to 98 percent, and more preferably 92 to 97 percent;

the specific surface area is 550-750m²G, preferably 600- & ltwbr/& gt700 m²G, more preferably 620-660m²(ii)/g; and/or

The weight percent of the sodium oxide is less than or equal to 0.1 percent, preferably less than or equal to 0.05 percent, and more preferably 0.01 to 0.05 percent.

In another preferred embodiment, in the second catalyst, the second metal active component is present in an amount of 0.5 to 20 wt%, preferably 1 to 15 wt%, more preferably 2 to 12 wt%, most preferably 4 to 10 wt%, and most preferably 4 to 8 wt% based on the weight of the modified cation exchange resin.

In another preferred embodiment, the zinc chloride is present in the second catalyst in an amount of 0.5 to 20 wt%, preferably 1 to 15 wt%, more preferably 2 to 12 wt%, most preferably 4 to 10 wt%, more preferably 4 to 8 wt% based on the weight of the modified cation exchange resin.

In another preferred embodiment, the weight percentage of the aluminum chloride in the second catalyst is 0.5-20 wt%, preferably 1-15 wt%, more preferably 2-12 wt%, most preferably 4-10 wt%, more preferably 4-8 wt% of the modified cation exchange resin.

In another preferred embodiment, the tin chloride is present in the second catalyst in an amount of 0.5 to 20 wt%, preferably 1 to 15 wt%, more preferably 2 to 12 wt%, most preferably 4 to 10 wt%, more preferably 4 to 8 wt% based on the weight of the modified cation exchange resin.

In another preferred embodiment, the ruthenium chloride is present in the second catalyst in an amount of 0.5 to 20 wt%, preferably 1 to 15 wt%, more preferably 2 to 12 wt%, most preferably 4 to 10 wt%, more preferably 4 to 8 wt% based on the weight of the modified cation exchange resin.

In another preferred embodiment, the weight ratio of the first catalyst to the second catalyst is 0.5-5: 1, preferably 0.5-4:1, more preferably 1-2:1, more preferably 1.2-2:1, more preferably 1.3-1.8: 1.

In another preferred embodiment, the cation exchange resin is a strong acid cation exchange resin.

In another preferred example, the cation exchange resin is a macroporous strong-acid styrene cation exchange resin.

In another preferred example, the functional group of the strong acid cation exchange resin is a sulfonic acid group.

In another preferred embodiment, the cation exchange resin is selected from the group consisting of: d61 macroporous strong acid cation exchange resin (Tianjinbo resin science and technology Co., Ltd.), NKC-9 cation exchange resin, D72 macroporous strong acid cation exchange resin, or a combination thereof.

In another preferred embodiment, the second catalyst is prepared by the following method:

(a) providing a cation exchange resin and a second metal active component;

(b) soaking cation exchange resin in strong acid to obtain modified cation exchange resin;

(c) and mixing the modified cation exchange resin and the second metal active component in an anhydrous solvent, reacting, and filtering to obtain the second catalyst.

In another preferred embodiment, the modified cation exchange resin is prepared by the following method:

(b) soaking cation exchange resin in strong acid to obtain modified cation exchange resin;

in another preferred embodiment, the strong acid is selected from the group consisting of: hydrochloric acid, sulfuric acid, or a combination thereof;

in another preferred embodiment, the concentration of the strong acid is 0.5 to 5mol/L, preferably 1 to 3 mol/L;

in another preferred embodiment, the strong acid is used in an amount of 2 to 20 times, preferably 5 to 15 times, more preferably 8 to 12 times the weight of the cation exchange resin;

in another preferred embodiment, the soaking temperature is 20-80 ℃, preferably 30-70 ℃, more preferably 35-45 ℃;

in another preferred embodiment, the soaking time is 2-30h, preferably 5-20h, more preferably 6-16 h;

in another preferred embodiment, the anhydrous solvent is selected from the group consisting of: anhydrous ethanol, anhydrous methanol, anhydrous acetone, or combinations thereof;

in another preferred embodiment, in the step (c), the temperature of the reaction is 60-90 ℃, preferably 70-90 ℃;

in another preferred embodiment, in the step (c), the reaction time is 3 to 12 hours, preferably 4 to 8 hours;

in another preferred example, in the step (c), after the reaction is finished, the reaction mixture is cooled to room temperature (20 ℃) and then filtered;

in another preferred embodiment, in the step (c), after filtration, the second catalyst is obtained after washing with anhydrous ether, acetone and deionized water in sequence and drying (e.g. 75-85 ℃);

in another preferred embodiment, the second catalyst is prepared by the following method:

(a) providing a cation exchange resin and a second metal active component;

(b) soaking cation exchange resin in strong acid for ion exchange, performing modification treatment, and drying to obtain modified cation exchange resin, wherein the concentration of hydrochloric acid is 0.5-5mol/L, the amount of hydrochloric acid is 2-20 times of the weight of the resin, the soaking time is 2-30h, the soaking temperature is 20-80 deg.C, and then drying at 40-80 deg.C;

(c) adding an anhydrous solvent solution of a second metal active component into the modified cation exchange resin, reacting at 60-90 ℃ for 3-12h, cooling to room temperature (20 ℃), filtering, washing with anhydrous ether, acetone and deionized water in sequence, and drying (such as 75-85 ℃) to obtain a second catalyst.

In another preferred embodiment, the drying temperature is 55-65 ℃.

In a second aspect of the present invention, there is provided a hydration catalyst, the hydration catalyst comprising a first catalyst and a second catalyst; the first catalyst is a solid acid catalyst, the solid acid catalyst comprises a solid acid and a first metal active component, the first metal active component is loaded on the solid acid, and the first metal active component is selected from the following group: platinum, nickel, or a combination thereof;

the second catalyst is modified cation exchange resin loaded with a second metal active component, the modified cation exchange resin is cation exchange resin soaked by strong acid, and the second metal active component is selected from the following group: zinc chloride, aluminum chloride, tin chloride, ruthenium chloride, rhodium chloride, or combinations thereof.

In another preferred embodiment, the hydration catalyst is the hydration catalyst of the first aspect of the invention.

It is to be understood that within the scope of the present invention, the above-described features of the present invention and those specifically described below (e.g., in the examples) may be combined with each other to form new or preferred embodiments. Not to be reiterated herein, but to the extent of space.

Detailed Description

The invention unexpectedly develops a preparation method of the lyral with high yield, high conversion rate, simple process and easy industrial production through extensive research. Experiments show that the solid acid catalyst of the zeolite loaded with platinum and nickel and the modified cation exchange resin loaded with the second metal active component can play a synergistic role, so that the selectivity and the conversion rate of the citral are remarkably improved.

Term(s) for

As used herein, the terms "comprises," "comprising," "includes," "including," and "including" are used interchangeably and include not only closed-form definitions, but also semi-closed and open-form definitions. In other words, the term includes "consisting of … …", "consisting essentially of … …".

As used herein, "zeolite beta" is also known as molecular sieve beta.

As used herein, "D72 macroporous strong acid cation exchange resin" is a macroporous strong acid styrenic cation exchange resin, also known as D72 macroporous strong acid styrenic cation exchange resin, whose functional group is a sulfonic acid group (-SO 3H).

As used herein. The terms "first catalyst" and "solid acid catalyst" are used interchangeably and include a solid acid and a first metal active component supported on the solid acid, the first metal active component being selected from the group consisting of: platinum, nickel, or a combination thereof.

Preparation method

The invention provides a preparation method of lyral, which comprises the following steps:

(1) in an organic solvent, under the action of a hydration catalyst, citral and water undergo a hydration reaction to generate lyral;

wherein the hydration catalyst comprises a first catalyst and a second catalyst;

the first catalyst is a solid acid catalyst, the solid acid catalyst comprises a solid acid and a first metal active component, the first metal active component is loaded on the solid acid, and the first metal active component is selected from the following group: platinum, nickel, or a combination thereof;

the second catalyst is modified cation exchange resin loaded with a second metal active component, the modified cation exchange resin is cation exchange resin soaked by strong acid, and the second metal active component is selected from the following group: zinc chloride, aluminum chloride, tin chloride, ruthenium chloride, rhodium chloride, or combinations thereof.

In a preferred embodiment of the present invention, in the step (1), the organic solvent is selected from the group consisting of: isopropanol, tetrahydrofuran, acetone, methyltetrahydrofuran, dioxane, acetic acid, acetate, or combinations thereof.

In another preferred embodiment, in the step (1), the reaction time is 5-12h, preferably 6-10 h.

In another preferred embodiment, in said step (1), said reaction temperature is 50-100 ℃, preferably 60-90 ℃, more preferably 70-90 ℃, most preferably 75-85 ℃.

In another preferred embodiment, in said step (1), the molar ratio of said myrac aldehyde to said water is 0.3 to 1:1, preferably 0.3 to 0.8:1, more preferably 0.4 to 0.6: 1.

in another preferred embodiment, in the step (1), the molar ratio of the organic solvent to the water is 0.5-1.5:0.5-1.5, preferably 0.8-1.2: 0.8-1.2.

In another preferred embodiment, the hydration catalyst is used in an amount of 0.5 to 10 wt%, preferably 0.5 to 8 wt%, more preferably 1 to 5 wt%, most preferably 1 to 3 wt% of the amount of the myrac aldehyde.

In another preferred embodiment, the weight ratio of the first catalyst to the second catalyst is 0.5-5: 1, preferably 0.5-4:1, more preferably 1-2:1, more preferably 1.2-2:1, more preferably 1.3-1.8: 1.

In the preparation method of the lyral of the invention, the raw material of the lyral has 2 double bonds, and in the hydration reaction, the hydroxyl can be connected with different carbon atoms of the 2 double bonds, so that a plurality of hydration reaction products can be generated (namely, different carbon atoms of the double bonds are connected with the hydroxyl).

In the method for producing lyral of the present invention, the selectivity (%) means the percentage of lyral produced by the reaction based on the amount of the substance of the product produced by the reaction (including the product formed by bonding different carbon atoms of the double bond to the hydroxyl group), for example, in the method for producing lyral of the present invention, 100mol of the product is produced, wherein lyral is 90mol, and the selectivity is 90%.

In the method for producing lyral of the present invention, the conversion rate (%) is calculated as the conversion rate of myrac aldehyde. For example, 100g of citral is used as a raw material, 60g of citral is reacted, and the conversion (%) is 60% of citral (60g) reacted based on 100g of citral charged.

In a preferred embodiment, the preparation method of the lyral provided by the invention comprises the steps of carrying out reaction in a reaction tower, sequentially layering through a continuous layering device, removing the solvent through a solvent removal tower, and rectifying to obtain the product lyral. The rectification can be carried out by adopting conventional rectification equipment. Preferably, the reaction and rectification are carried out by: and continuously pumping the materials in the batching kettle into the reactor through a delivery pump, and feeding the materials flowing through the tail end of the reactor into the delayer. After materials in the delaminating device are delaminated, the upper layer mainly comprises a solvent, citral and the neocarling aldehyde generated by the reaction, the continuous rectifying tower is directly carried out, and the citral and the solvent flow out of the tower top and return to the batching kettle; the materials at the lower layer of the delaminator mainly comprise water and a solvent, and enter the batching kettle together with the materials which are not discharged from the rectifying tower. And transferring the tower kettle materials of the rectifying tower kettle to a secondary rectifying tower through a delivery pump for secondary rectifying separation. The lyral extracted from the rectifying tower can enter a finished product storage tank because of containing a trace amount of myrac aldehyde, the finished product can be sold in the market II or enter a fractionating tower, and the high-purity lyral extracted by simple re-rectification enters the finished product storage tank.

Hydration catalyst

In the preparation method of the lyral, under the action of a hydration catalyst, the lyral and water generate hydration reaction to generate the lyral.

Typically, the hydration catalyst of the present invention comprises a first catalyst and a second catalyst.

First catalyst

In the present invention, the first catalyst is a solid acid catalyst, the solid acid catalyst comprises a solid acid and a first metal active component, the first metal active component is supported on the solid acid, and the first metal active component is selected from the following group: platinum, nickel, or a combination thereof;

in a preferred embodiment of the present invention, the weight percentage of the first metal active component in the solid acid catalyst is 0.5-8 wt%, preferably 1-4 wt%.

In another preferred embodiment, the solid acid catalyst is prepared by a process comprising the steps of:

impregnating a solid acid with a solution of a material selected from the group consisting of: dipping chloroplatinic acid, nickel nitrate hexahydrate or a combination thereof, drying, and roasting to obtain a solid acid catalyst;

the solid acid is selected from the following group: zeolite, silica, alumina, or combinations thereof.

In another preferred embodiment, the temperature of drying after impregnation is 100-150 ℃.

In another preferred embodiment, the temperature for the calcination is 400-550 ℃, preferably 450-520 ℃.

Preferably, the platinum is present in an amount of 0.1 to 2.5 wt%, preferably 0.1 to 2 wt%, more preferably 0.1 to 1.5 wt%, more preferably 0.2 to 0.8 wt%, and most preferably 0.3 to 0.7 wt% based on the weight of the solid acid catalyst.

Preferably, the nickel is present in an amount of 0.05 to 1.5 wt%, preferably 0.08 to 1.0 wt%, more preferably 0.08 to 0.5 wt%, and most preferably 0.1 to 0.3 wt% based on the weight of the solid acid catalyst.

In another preferred embodiment, the solid acid is zeolite.

In another preferred embodiment, the zeolite is selected from the group consisting of: natural zeolite, beta zeolite, Y zeolite, MCM-22, ZSM-5, or a combination thereof.

In another preferred embodiment, the SiO of the β zeolite₂/Al₂O₃(molar ratio) is 20 to 100, preferably 20 to 40, more preferably 20 to 30.

In another preferred embodiment, the beta zeolite is Cation Type H.

In another preferred embodiment, the beta zeolite further has one or more characteristics selected from the group consisting of:

SiO₂/Al₂O₃(molar ratio) of 20 to 100, preferably 20 to 40, more preferably 20 to 30;

the crystallinity is more than or equal to 90 percent, preferably 90 to 98 percent, and more preferably 92 to 97 percent;

the specific surface area is 550-750m²G, preferably 600- & ltwbr/& gt700 m²G, more preferably 620-660m²(ii)/g; and/or

The wt.% of sodium oxide is less than or equal to 0.1%, preferably less than or equal to 0.05%, more preferably 0.01-0.05%.

Second catalyst

In the invention, the second catalyst is a modified cation exchange resin loaded with a second metal active component, the modified cation exchange resin is a cation exchange resin soaked by strong acid, and the second metal active component is selected from the following group: zinc chloride, aluminum chloride, tin chloride, ruthenium chloride, rhodium chloride, or combinations thereof.

In a preferred embodiment of the present invention, in the second catalyst, the second metal active component accounts for 0.5-20 wt%, preferably 1-15 wt%, more preferably 2-12 wt%, most preferably 4-10 wt%, and most preferably 4-8 wt% of the modified cation exchange resin.

Preferably, the weight percentage of the zinc chloride in the second catalyst to the modified cation exchange resin is 0.5 to 20 wt%, preferably 1 to 15 wt%, more preferably 2 to 12 wt%, most preferably 4 to 10 wt%, more preferably 4 to 8 wt%.

Preferably, in the second catalyst, the aluminum chloride accounts for 0.5-20 wt%, preferably 1-15 wt%, more preferably 2-12 wt%, most preferably 4-10 wt%, more preferably 4-8 wt% of the modified cation exchange resin.

Preferably, in the second catalyst, the tin chloride is present in an amount of 0.5 to 20 wt%, preferably 1 to 15 wt%, more preferably 2 to 12 wt%, most preferably 4 to 10 wt%, more preferably 4 to 8 wt% based on the weight of the modified cation exchange resin.

Preferably, the ruthenium chloride is present in the second catalyst in an amount of 0.5 to 20 wt%, preferably 1 to 15 wt%, more preferably 2 to 12 wt%, most preferably 4 to 10 wt%, more preferably 4 to 8 wt%, based on the weight of the modified cation exchange resin.

In another preferred embodiment, the cation exchange resin is a strong acid cation exchange resin.

In another preferred example, the cation exchange resin is a macroporous strong-acid styrene cation exchange resin.

In another preferred example, the functional group of the strong acid cation exchange resin is a sulfonic acid group.

Typically, the cation exchange resin is selected from the group consisting of: d61 macroporous strong acid cation exchange resin (Tianjinbo resin science and technology Co., Ltd.), NKC-9 cation exchange resin, D72 macroporous strong acid cation exchange resin, or a combination thereof.

In another preferred embodiment, the second catalyst is prepared by the following method:

(a) providing a cation exchange resin and a second metal active component;

(b) soaking cation exchange resin in strong acid to obtain modified cation exchange resin;

(c) and mixing the modified cation exchange resin and the second metal active component in an anhydrous solvent, reacting, and filtering to obtain the second catalyst.

In another preferred embodiment, the strong acid is selected from the group consisting of: hydrochloric acid, sulfuric acid, or a combination thereof.

In another preferred embodiment, the concentration of the strong acid is 0.5 to 5mol/L, preferably 1 to 3 mol/L.

In another preferred embodiment, the strong acid is used in an amount of 2 to 20 times, preferably 5 to 15 times, more preferably 8 to 12 times the weight of the cation exchange resin.

In another preferred embodiment, the temperature of said soaking is 20-80 ℃, preferably 30-70 ℃, more preferably 35-45 ℃.

In another preferred embodiment, the soaking time is 2-30h, preferably 5-20h, more preferably 6-16 h.

In another preferred embodiment, the anhydrous solvent is selected from the group consisting of: anhydrous ethanol, anhydrous methanol, anhydrous acetone, or combinations thereof.

In another preferred embodiment, in the step (c), the temperature of the reaction is 60 to 90 ℃, preferably 70 to 90 ℃.

In another preferred embodiment, in the step (c), the reaction time is 3-12h, preferably 4-8 h.

In another preferred embodiment, in the step (c), after the reaction is finished, the reaction mixture is cooled to room temperature (20 ℃) and then filtered.

In another preferred embodiment, in the step (c), after filtration, the second catalyst is obtained after washing with anhydrous ether, acetone and deionized water in sequence and drying (e.g., 75-85 ℃).

The main excellent technical effects obtained by the invention comprise:

the invention unexpectedly develops a method for preparing the lyral, which has the excellent technical effects of high selectivity, high yield, high conversion rate and the like, and the method for preparing the lyral by the one-step hydration method has simple process and is suitable for industrial production.

The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The experimental procedures, in which specific conditions are not noted in the following examples, are generally carried out under conventional conditions or conditions recommended by the manufacturers. Unless otherwise indicated, percentages and parts are by weight.