阅读说明：本技术 一种丝光沸石分子筛、其制备方法及应用 (Mordenite molecular sieve, and preparation method and application thereof ) 是由 李凌云 田鹏 王全义 刘中民 于 2018-06-20 设计创作，主要内容包括：本申请公开了一种丝光沸石分子筛,其特征在于,所述丝光沸石分子筛为毫米级球形分子筛；所述丝光沸石分子筛由微米级的片状丝光沸石晶体组装得到；所述丝光沸石分子筛的比表面积为200～500m<Sup>2</Sup>·g<Sup>-1</Sup>,孔体积为0.1～0.3cm<Sup>3</Sup>·g<Sup>-1</Sup>。该分子筛为适用于固定床和移动床反应器的无粘结剂球形丝光沸石,其大小在一定范围内可调,宏观上具有毫米级球形结构,具有较高的机械强度。本申请还公开了其制备方法及在酸催化反应、含氧化合物转化制羰基化合物反应中的应用,该方法原料转化效率高,处理过程简单、高效,采用该方法制备得到的丝光沸石分子筛用作催化剂时表现出良好的催化性能。(The application discloses a mordenite molecular sieve, which is characterized in that the mordenite molecular sieve is a millimeter-scale spherical molecular sieve; the mordenite molecular sieve is assembled by micron-sized flaky mordenite crystals; the specific surface area of the mordenite molecular sieve is 200-500 m 2 ·g ‑1 Pore volume of 0.1-0.3 cm 3 ·g ‑1 . The molecular sieve is binderless spherical mordenite suitable for fixed bed and moving bed reactors, and has adjustable size in a certain range, a millimeter-scale spherical structure in a macroscopic view, and high mechanical strength. The application also discloses a preparation method thereof and application of the catalyst in the reactions of acid catalysis reaction and carbonyl compound preparation through conversion of oxygen-containing compoundThe method has the advantages of high conversion efficiency of raw materials, simple and efficient treatment process, and good catalytic performance when the mordenite molecular sieve prepared by the method is used as a catalyst.)

1. A mordenite molecular sieve, wherein said mordenite molecular sieve is a millimeter-sized spherical molecular sieve;

the mordenite molecular sieve is assembled by micron-sized flaky mordenite crystals;

the specific surface area of the mordenite molecular sieve is 200-500 m²·g^-1Pore volume of 0.1-0.3 cm³·g^-1。

2. A mordenite molecular sieve as claimed in claim 1, wherein the mordenite molecular sieve has a size of 2 to 3 mm;

the size of the flaky mordenite crystals is 2-5 mu m.

3. A process for the preparation of a mordenite molecular sieve as claimed in claim 1 or 2, which comprises: heating and crystallizing spherical silicon dioxide serving as a precursor in a steam atmosphere containing a nitrogen-containing compound and water to obtain the mordenite molecular sieve;

the nitrogen-containing compound comprises at least one of ammonia, organic amine and quaternary ammonium base.

4. A method for preparing the mordenite molecular sieve of claim 3, wherein the spherical silica has a pore volume of 0.1-1.0 cm³·g^-1The specific surface area is 100 to 600m²·g^-1The average pore diameter is 2-50 nm;

preferably, the pore volume of the spherical silicon dioxide is 0.4-0.8 cm³·g^-1The specific surface area is 100 to 300m²·g^-1The average pore diameter is 2-20 nm;

the molar ratio of the nitrogen-containing compound to water is 0.001-0.05: 1;

preferably, the nitrogen-containing compound is selected from at least one of ammonia, diethylamine, diethanolamine, diisopropylamine, triethylamine, n-butylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide and cyclohexylimine;

preferably, the heating crystallization condition is crystallization at 150-220 ℃ for 24-144 hours.

Preferably, the temperature for heating and crystallizing is 160-210 ℃; the heating crystallization time is 24-120 hours;

preferably, the thermal crystallization is performed under a closed condition.

5. A process for the preparation of a mordenite molecular sieve as claimed in claim 3, which process comprises the steps of:

(1) spherical silicon dioxide is used as a silicon source, and a spherical molecular sieve precursor is obtained by pretreating a load aluminum source;

(2) and (2) heating and crystallizing the spherical molecular sieve precursor in the step (1) in a steam atmosphere containing a nitrogen-containing compound and water, and removing organic matters to obtain the mordenite molecular sieve.

6. The method according to claim 5, wherein the pretreatment in the step (1) comprises:

a) preparation of an impregnation solution: dissolving an aluminum source, an alkali source and an amine/ammonium substance in water according to a ratio, and uniformly stirring to obtain a dipping solution;

b) preparing a spherical molecular sieve precursor: dipping the spherical silicon dioxide in the dipping solution obtained in the step a), and filtering to obtain a spherical molecular sieve precursor;

the removing of the organic matter in the step (2) includes: roasting for 4-10 hours at 400-700 ℃;

preferably, the step (2) specifically comprises: adding the spherical molecular sieve precursor in the step (1) into a reactor containing mixed liquid containing nitrogen-containing compounds and water, sealing, aging, heating, crystallizing, washing, filtering, drying, and removing organic matters to obtain the mordenite molecular sieve; wherein, the spherical molecular sieve precursor is prevented from directly contacting with the liquid in the reaction kettle.

7. The preparation method according to claim 6, wherein the aluminum source is calculated by alumina, and the molar ratio of the aluminum source to the water in the step a) is Al₂O₃/H₂O＝0.001～0.05：1；

The alkali source is calculated by an alkali metal M, and the molar ratio of the alkali source to the water in the step a) is M/H₂O＝0.01～0.5：1；

The molar ratio of the amine/ammonium substance to water in the step a) is 0.001-0.1: 1;

preferably, the aluminium source in step a) is selected from at least one of pseudoboehmite, aluminium hydroxide, aluminium nitrate, aluminium chloride, aluminium sulphate or sodium aluminate;

preferably, the alkali source in step a) is an oxide and/or hydroxide of a basic metal M; further preferably, the basic metal M is at least one selected from lithium, sodium and potassium;

preferably, the amine/ammonium species in step a) is selected from at least one of diethylamine, diethanolamine, diisopropylamine, triethylamine, n-butylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, cyclohexylimine;

the volume ratio of the spherical silicon dioxide to the dipping solution in the step b) is 0.1-0.5: 1;

the dipping temperature in the step b) is 20-60 ℃, and the dipping time is not less than 5 minutes;

the mixed liquid comprises at least one of water, ammonia water, diethylamine, diisopropylamine, triethylamine, n-butylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide and cyclohexylimine;

the molar ratio of the nitrogen-containing compound to water in the mixed liquid is 0.001-0.05: 1;

preferably, the molar ratio of the nitrogen-containing compound to water in the mixed liquid is 0.001-0.05: 1;

preferably, the aging treatment is aging for 0.5 to 12 hours at a temperature of 80 to 120 ℃;

preferably, the drying condition is drying at 100-120 ℃ for 6-12 hours.

8. The method for preparing according to claim 3, characterized in that it comprises the steps of:

a) preparation of an impregnation solution: dissolving an aluminum source, an alkali source and an amine/ammonium substance in water according to a ratio, and uniformly stirring to obtain a dipping solution;

b) preparing a spherical molecular sieve precursor: dipping the spherical silicon dioxide in the dipping solution obtained in the step a), and filtering to obtain a spherical molecular sieve precursor;

c) preparing a spherical mordenite molecular sieve: pre-adding a mixed liquid containing a nitrogen compound and water into a reaction kettle, placing the spherical molecular sieve precursor in the step b) into the reaction kettle, and avoiding the precursor from directly contacting the mixed liquid; after the reaction kettle is sealed, carrying out aging treatment and crystallization treatment, washing, drying and roasting to obtain the mordenite molecular sieve;

the molar ratio of the nitrogen-containing compound to the spherical molecular sieve precursor in the step c) is 0.05-2: 1;

in the step c), the roasting condition is that roasting is carried out for 4-10 hours at 400-700 ℃.

9. An acid catalytic reaction catalyst, which is obtained by ion exchange of at least one of the mordenite molecular sieve of claim 1 and the mordenite molecular sieve prepared by the method of any one of claims 2 to 8 to remove alkali metal ions, and then roasting in air at 400-700 ℃.

10. A catalyst for the reaction of converting an oxygen-containing compound to a carbonyl compound, wherein the catalyst is prepared by ion exchange of at least one of the mordenite molecular sieve of claim 1 and the mordenite molecular sieve prepared by the method of any one of claims 2 to 8 to remove alkali metal ions, and roasting at 400-700 ℃ in air.

Technical Field

The application relates to a mordenite molecular sieve, a preparation method and application thereof, belonging to the fields of chemistry and chemical engineering and catalyst preparation.

Background

The molecular sieve plays an important role in the catalytic process, and has great economic benefit when being applied to the reaction processes of catalytic cracking, aromatic isomerization, methanol-to-olefin and the like. The molecular sieve obtained by the traditional method is powdery and cannot be directly applied to an industrial reactor. It is generally necessary to carry out a shaping process to obtain a particulate catalyst. Since molecular sieves are inherently barren materials, binders must be added to increase mechanical strength. The inorganic binder remains in the catalyst, causing a decrease in the molecular sieve content of the catalyst and a consequent decrease in the activity of the catalyst. The binder also affects the diffusion of reactants, leading to deactivation of the carbon deposits and affecting catalyst life. Although the organic binder can be removed during roasting, the production cost of the catalyst is increased, the economy is not high, and the roasting of the organic matter causes certain pollution to the environment, which does not accord with the theme of energy conservation and environmental protection at present.

In order to overcome the problems associated with the prior art molecular sieves during the molding process, binder-free synthesis of molecular sieve catalysts has been developed and can be divided into two broad categories, namely the direct synthesis of zeolite blocks and the conversion of the binder into molecular sieves. Usually, the binder and the molecular sieve are mixed and formed, and the molecular sieve catalyst without the binder is obtained by crystallization under the hydrothermal condition. Because the catalyst does not contain a binder, the content of active components in the catalyst is increased, and the corresponding reaction activity is also improved. The molecular sieve has smooth pore passages, and the problem that the pore passages are blocked by the binder to influence the diffusion does not exist. However, the former has low production efficiency and cannot be applied in large scale, and the latter generally utilizes extrusion molding to obtain a strip-shaped molecular sieve, and a pore-forming agent is added in the extrusion process in order to prevent the problem of reduction of void ratio caused by extrusion.

Mordenite has 12-membered ring and 8-membered ring channel structures, and has excellent catalytic reaction performance in fixed bed reactions such as aromatic hydrocarbon isomerization, dimethyl ether carbonylation and the like, so that the mordenite is applied to petroleum refining and petrochemical processes. The spherical catalyst is a preferable shape of the fixed bed catalyst because it facilitates the catalyst loading in an industrial apparatus and can reduce the channeling phenomenon. U.S. patent USP 4935217 reports crystallization of micron-sized volcanic glasses in alkaline solution to obtain MOR zeolite particles at crystallization temperatures around 200 ℃. However, the method has the problems that the particles are too small to control the shape of the particles, the crystallization temperature is too high, and the like.

Disclosure of Invention

According to one aspect of the application, a mordenite molecular sieve is provided, which is an adhesive-free spherical mordenite molecular sieve suitable for fixed bed and moving bed reactors, the size of the molecular sieve is adjustable within a certain range, the molecular sieve macroscopically has a millimeter-scale spherical structure, and the molecular sieve has high mechanical strength and high thermal stability and hydrothermal stability.

The mordenite molecular sieve is a millimeter-sized spherical molecular sieve;

the mordenite molecular sieve is assembled by micron-sized flaky mordenite crystals;

the specific surface area of the mordenite molecular sieve is 200-500 m²·g^-1Pore volume of 0.1 to 0.3

3-1

cm·g。

Optionally, the size of the mordenite molecular sieve is 2-3 mm.

Optionally, the size of the mordenite molecular sieve crystals is 2-5 μm.

Optionally, the silicon-aluminum ratio (Si/Al) of the mordenite molecular sieve is between 10 and 12.

According to another aspect of the application, the preparation method of the mordenite molecular sieve is provided, in the method, the molecular sieve does not need a forming process, the raw material conversion efficiency is high, compared with the traditional hydrothermal synthesis, the product exists in a particle form in the whole preparation process, the powder can be avoided in the production process, so that the processes of centrifugation, forming and the like are omitted, and the treatment process is simple and efficient.

The preparation method of the mordenite molecular sieve is characterized by comprising the following steps: and (3) heating and crystallizing spherical silicon dioxide serving as a precursor in a steam atmosphere containing a nitrogen-containing compound and water to obtain the mordenite molecular sieve.

Optionally, the nitrogen-containing compound comprises at least one of ammonia, an organic amine, and a quaternary ammonium base.

Optionally, the pore volume of the spherical silicon dioxide is 0.1-1.0 cm³·g^-1The specific surface area is 100 to 600m²·g^-1The average pore diameter is 2 to 50 nm.

Optionally, the pore volume of the spherical silicon dioxide is 0.4-0.8 cm³·g^-1The specific surface area is 100 to 300m²·g^-1The average pore diameter is 2-20 nm.

Optionally, the molar ratio of the nitrogen-containing compound to water is 0.001 to 0.05: 1.

alternatively, the lower limit of the molar ratio of the nitrogen-containing compound to water is independently selected from 0.001:1, 0.005:1, 0.01:1, 0.015:1, 0.02:1, 0.025:1, 0.03:1, 0.035:1, 0.04:1, 0.045:1, 0.05:1, and any point in the range consisting of any two of the above points.

Optionally, the upper limit of the molar ratio of the nitrogen-containing compound to water is independently selected from 0.005:1, 0.01:1, 0.015:1, 0.02:1, 0.025:1, 0.03:1, 0.035:1, 0.04:1, 0.045:1, 0.05:1, and any point in the range consisting of any two of the foregoing.

Optionally, the nitrogen-containing compound is selected from at least one of ammonia, diethylamine, diethanolamine, diisopropylamine, triethylamine, n-butylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide and cyclohexylimine.

Optionally, the heating crystallization condition is crystallization at 150-220 ℃ for 24-144 hours.

Optionally, the temperature of the heating crystallization is 160-210 ℃; the heating crystallization time is 24-120 hours.

Optionally, the lower temperature limit for thermal crystallization is independently selected from 150 ℃, 160 ℃, 165 ℃, 170 ℃, 175 ℃, 180 ℃, 185 ℃, 190 ℃, 195 ℃, 200 ℃, 210 ℃, and any point in a range consisting of any two of the above points.

Optionally, the upper temperature limit for thermal crystallization is independently selected from 165 ℃, 170 ℃, 175 ℃, 180 ℃, 185 ℃, 190 ℃, 195 ℃, 200 ℃, 210 ℃, 220 ℃, and any point in a range consisting of any two of the above points.

Optionally, the lower limit of the time for thermal crystallization is independently selected from 24h, 36h, 48h, 60h, 72h, 78h, 84h, 90h, 96h, 120h, 144h, and any point in a range consisting of any two of the above points.

Optionally, the upper time limit for thermal crystallization is independently selected from 25h, 36h, 48h, 60h, 72h, 78h, 84h, 90h, 96h, 120h, 144h, and any point in a range consisting of any two of the above points.

Optionally, the thermal crystallization is performed under a closed condition.

Optionally, the method comprises the steps of:

(1) spherical silicon dioxide is used as a silicon source, and a spherical molecular sieve precursor is obtained by pretreating a load aluminum source;

(2) and (2) heating and crystallizing the spherical molecular sieve precursor in the step (1) in a steam atmosphere containing a nitrogen-containing compound and water, and removing organic matters to obtain the mordenite molecular sieve.

Optionally, the pre-processing in step (1) comprises:

a) preparation of an impregnation solution: dissolving an aluminum source, an alkali source and an amine/ammonium substance in water according to a ratio, and uniformly stirring to obtain a dipping solution;

b) preparing a spherical molecular sieve precursor: dipping the spherical silicon dioxide in the dipping solution obtained in the step a), and filtering to obtain a spherical molecular sieve precursor.

Optionally, the removing the organic matter in the step (2) includes: roasting for 4-10 hours at 400-700 ℃.

Optionally, the step (2) specifically includes: adding the spherical molecular sieve precursor in the step (1) into a reactor containing mixed liquid containing nitrogen-containing compounds and water, sealing, aging, heating, crystallizing, washing, filtering, drying, and removing organic matters to obtain the mordenite molecular sieve; wherein, the spherical molecular sieve precursor is prevented from directly contacting with the liquid in the reaction kettle.

Optionally, the aluminum source is calculated by alumina, and the molar ratio of the aluminum source to the water in the step a) is Al₂O₃/H₂O＝0.001～0.05：1。

Alternatively, the lower limit of the molar ratio of the aluminum source to water in step a) is independently selected from 0.001:1, 0.005:1, 0.01:1, 0.015:1, 0.02:1, 0.025:1, 0.03:1, 0.035:1, 0.04:1, 0.405:1, 0.05:1, and any two of the above ranges.

Alternatively, the aluminum source is calculated as alumina, and the upper limit of the molar ratio of the aluminum source to the water in step a) is independently selected from 0.002:1, 0.005:1, 0.01:1, 0.015:1, 0.02:1, 0.025:1, 0.03:1, 0.035:1, 0.04:1, 0.405:1, 0.05:1, and any two of the above ranges.

Optionally, the aluminum source is calculated by alumina, and the molar ratio of the aluminum source to the water in the step a) is Al₂O₃/H₂O＝0.01～0.03：1。

Optionally, the alkali source is calculated by a basic metal M, and the molar ratio of the alkali source to the water in the step a) is M/H₂O＝0.01～0.5：1。

Alternatively, the lower limit of the molar ratio of the alkali source to water in step a) is independently selected from 0.01:1, 0.05:1, 0.1:1, 0.15:1, 0.2:1, 0.25:1, 0.3:1, 0.35:1, 0.4:1, 0.45:1, 0.5:1, and any point in a range consisting of any two of the above points.

Optionally, the upper limit of the molar ratio of the alkali source to water in step a) is independently selected from 0.02:1, 0.05:1, 0.1:1, 0.15:1, 0.2:1, 0.25:1, 0.3:1, 0.35:1, 0.4:1, 0.45:1, 0.5:1, and any point in a range consisting of any two of the above points.

Optionally, the molar ratio of the alkali source to water in step a) is M/H₂O＝0.1～0.5：1。

Optionally, the molar ratio of the amine/ammonium species to water in step a) is 0.001-0.1: 1.

optionally, the lower limit of the molar ratio of amine/ammonium species to water in step a) is independently selected from 0.001:1, 0.005:1, 0.01:1, 0.015:1, 0.02:1, 0.025:1, 0.03:1, 0.035:1, 0.04:1, 0.045:1, 0.05:1, 0.06:1, 0.07:1, 0.08:1, 0.09:1, 0.1:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1, and any two of the above ranges.

Optionally, the upper limit of the molar ratio of the amine/ammonium species to water in step a) is independently selected from 0.002:1, 0.005:1, 0.01:1, 0.015:1, 0.02:1, 0.025:1, 0.03:1, 0.035:1, 0.04:1, 0.045:1, 0.05:1, 0.06:1, 0.07:1, 0.08:1, 0.09:1, 0.1:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1, and any two of the above ranges.

Optionally, the molar ratio of the amine/ammonium species to water in step a) is 0.001-0.05: 1.

optionally, the molar ratio of the amine/ammonium species to water in step a) is 0.005-0.04: 1.

optionally, the aluminium source in step a) is selected from at least one of pseudoboehmite, aluminium hydroxide, aluminium nitrate, aluminium chloride, aluminium sulphate or sodium aluminate.

Optionally, the alkali source in step a) is an oxide and/or hydroxide of a basic metal M; further preferably, the basic metal M is at least one selected from lithium, sodium and potassium.

Optionally, the amine/ammonium species in step a) is selected from at least one of diethylamine, diethanolamine, diisopropylamine, triethylamine, n-butylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, cyclohexylimine.

Optionally, the volume ratio of the spherical silica to the impregnation solution in the step b) is 0.1-0.5: 1.

alternatively, the lower limit of the volume ratio of the spherical silica to the impregnating solution in step b) is independently selected from 0.1:1, 0.15:1, 0.2:1, 0.25:1, 0.3:1, 0.35:1, 0.4:1, 0.45:1, 0.5:1, and any point in the range consisting of any two of the above points.

Optionally, the upper limit of the volume ratio of the spherical silica to the impregnating solution in step b) is independently selected from 0.15:1, 0.2:1, 0.25:1, 0.3:1, 0.35:1, 0.4:1, 0.45:1, 0.5:1, and any point in the range consisting of any two of the above points.

Optionally, the temperature of the impregnation in the step b) is 20-60 ℃, and the time of the impregnation is not less than 5 minutes.

As a specific embodiment, the dipping temperature in the step b) is 20-60 ℃, and the dipping time is not less than 5 minutes. The impregnated and filtered microspheres can be dried and used in step (2) (the drying temperature is not higher than 120 ℃) or directly used in step (2).

Optionally, the mixed liquid comprises at least one of water, ammonia water, diethylamine, diisopropylamine, triethylamine, n-butylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, and cyclohexylimine.

Optionally, the molar ratio of the nitrogen-containing compound to water in the mixed liquid is 0.001-0.05: 1.

optionally, the lower limit of the molar ratio of nitrogen-containing compound to water in the mixed liquid is independently selected from 0.001:1, 0.005:1, 0.01:1, 0.015:1, 0.02:1, 0.025:1, 0.03:1, 0.035:1, 0.04:1, 0.045:1, 0.05:1, and any point in the range of any two of the above points.

Optionally, the upper limit of the molar ratio of nitrogen-containing compound to water in the mixed liquid is independently selected from 0.002:1, 0.005:1, 0.01:1, 0.015:1, 0.02:1, 0.025:1, 0.03:1, 0.035:1, 0.04:1, 0.045:1, 0.05:1, and any point in the range of any two of the above points.

Optionally, the method comprises the steps of:

a) preparing a dipping solution: dissolving an aluminum source, an alkali source and an amine/ammonium substance in water according to a ratio, and uniformly stirring to obtain a dipping solution;

b) preparing a spherical molecular sieve precursor: dipping the spherical silicon dioxide in the dipping solution obtained in the step a), and filtering to obtain a spherical molecular sieve precursor;

c) preparing a spherical mordenite molecular sieve: pre-adding a mixed liquid containing a nitrogen compound and water into a reaction kettle, placing the spherical molecular sieve precursor in the step b) into the reaction kettle, and avoiding the precursor from directly contacting the mixed liquid; and after the reaction kettle is sealed, carrying out aging treatment and crystallization treatment, washing, drying and roasting to obtain the mordenite molecular sieve.

Optionally, the molar ratio of the nitrogen-containing compound to the spherical molecular sieve precursor in the step c) is 0.05-2: 1.

alternatively, the lower limit of the molar ratio of the nitrogen-containing compound to the spherical molecular sieve precursor in step c) is independently selected from 0.05:1, 0.1:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, 1.2:1, 1.5:1, 2:1, and any point in the range consisting of any two of the above points.

Optionally, the upper limit of the molar ratio of the nitrogen-containing compound to the spherical molecular sieve precursor in step c) is independently selected from 0.05:1, 0.1:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, 1.2:1, 1.5:1, 2:1, and any point in the range consisting of any two of the above points.

Optionally, the aging treatment in the step c) is aging for 0.5 to 12 hours at a temperature of 80 to 120 ℃.

Optionally, the lower temperature limit of the aging treatment in step c) is independently selected from 80 ℃, 85 ℃, 90 ℃, 95 ℃, 100 ℃, 105 ℃, 110 ℃, 115 ℃, 120 ℃, and any point in a range consisting of any two of the above points.

Optionally, the upper temperature limit of the aging treatment in step c) is independently selected from 80 ℃, 85 ℃, 90 ℃, 95 ℃, 100 ℃, 105 ℃, 110 ℃, 115 ℃, 120 ℃, and any point in a range consisting of any two of the above points.

Optionally, the lower time limit of the aging treatment in step c) is independently selected from 0.5h, 1h, 2h, 3h, 4h, 5h, 6h, 6.5h, 7h, 8.5h, 9h, 10h, 11h, 12h, and any of the ranges consisting of any two of the above points.

Optionally, the upper time limit of the aging treatment in step c) is independently selected from 1h, 2h, 3h, 4h, 5h, 6h, 6.5h, 7h, 8.5h, 9h, 10h, 11h, 12h, and any of the ranges consisting of any two of the above points.

Optionally, the drying condition in the step c) is drying at 100-120 ℃ for 6-12 hours.

Optionally, the roasting condition in the step c) is roasting at 400-700 ℃ for 4-10 hours.

As a specific embodiment, the method comprises the steps of:

a) preparing a dipping solution: dissolving an aluminum source, an alkali source and an amine/ammonium substance in a certain proportion in a certain amount of deionized water, and uniformly stirring;

b) preparing a precursor of the spherical mordenite molecular sieve: dipping the silicon dioxide pellets in the solution prepared in the step a), and filtering to obtain a spherical mordenite precursor;

c) preparing a spherical mordenite molecular sieve: pre-adding a mixed liquid containing a nitrogen compound and water into a reaction kettle, and placing the precursor in the step b) into a polytetrafluoroethylene lining in the reaction kettle, wherein the distance between the precursor and the liquid at the bottom of the reaction kettle is 4-5 cm; aging the sealed reaction kettle at 80-120 deg.c for 0.5-12 hr; then heating to 160-220 ℃ for crystallization for 24-120 hours, washing the solid product to be neutral by deionized water, filtering, drying at 100-120 ℃ for 6-12 hours, and roasting at 400-700 ℃ for 4-10 hours to remove organic matters, thus obtaining the spherical mordenite.

In order to overcome the defects of adverse effect generated in the presence of a binder and poor strength of the existing molecular sieve catalyst, the application provides the preparation method of the binder-free spherical mordenite suitable for the fixed bed reactor.

In the application, a silicon-aluminum precursor is obtained by taking a silicon dioxide pellet as a silicon source and loading an aluminum source and the like, and the precursor is crystallized in situ by using a vapor phase-assisted synthesis method to obtain the spherical mordenite molecular sieve. The method has simple process, and can obtain high-strength microspheres with high molecular sieve content. Meanwhile, the molecular sieve catalyst prepared by the method shows higher catalytic performance in the reaction of preparing carbonyl compounds by converting oxygen-containing compounds.

According to still another aspect of the present application, there is provided an acid-catalyzed reaction catalyst which can be directly applied to industrial fixed bed and moving bed reactors and exhibits good catalytic performance.

The acid catalytic reaction catalyst is prepared by removing alkali metal ions from at least one of the mordenite molecular sieve and the mordenite molecular sieve prepared by any one of the methods through ion exchange, and roasting at 400-700 ℃ in air.

Alternatively, the acid-catalyzed reaction includes, but is not limited to, dimethyl ether carbonylation, n-butene isomerization, acetylation.

According to still another aspect of the present application, there is provided a reaction catalyst for converting an oxygenate to a carbonyl compound, which can be directly applied to industrial fixed bed and moving bed reactors and exhibits good catalytic performance.

The catalyst for the reaction of converting the oxygen-containing compound to prepare the carbonyl compound is prepared by removing alkali metal ions from at least one of the mordenite molecular sieve and the mordenite molecular sieve prepared by any one of the methods through ion exchange, and roasting the mordenite molecular sieve in air at the temperature of 400-700 ℃.

Alternatively, the reaction for preparing carbonyl compound by converting the oxygen-containing compound comprises but is not limited to methanol carbonylation reaction and dimethyl ether carbonylation reaction.

Benefits that can be produced by the present application include, but are not limited to:

1) the mordenite molecular sieve provided by the application is an adhesive-free spherical mordenite molecular sieve suitable for a fixed bed reactor, the size of the mordenite molecular sieve is adjustable within a certain range, and the mordenite molecular sieve has a millimeter-scale spherical structure in a macroscopic view and has higher mechanical strength.

2) In the preparation method of the mordenite molecular sieve, the molecular sieve does not need a forming process, the conversion efficiency of raw materials is up to more than 90%, compared with the traditional hydrothermal synthesis, the product exists in a particle form in the whole preparation process, and powder can be avoided in the production process, so that the processes of centrifugation, forming and the like are omitted, the treatment process is simple and efficient, and the spherical mordenite molecular sieve prepared by the method has higher crushing strength and adjustable size in a certain range.

3) The catalyst based on the mordenite molecular sieve can be directly applied to industrial fixed bed and moving bed reactors, shows good catalytic performance and has high thermal stability and hydrothermal stability.

Drawings

Figure 1 is an XRD spectrum of the mordenite molecular sieve prepared in example 2 of the present application.

Figure 2 is an optical photograph of a mordenite molecular sieve prepared in example 2 of the present application.

Figure 3 is an SEM image of the mordenite molecular sieve prepared in example 2 of the present application.

FIG. 4 is a graph of the nitrogen physisorption isotherm and pore size distribution of the mordenite molecular sieve prepared in example 2 of the present application.

Detailed Description

The present application will be described in detail with reference to examples, but the present application is not limited to these examples.

Unless otherwise specified, the raw materials in the examples of the present application were all purchased commercially, wherein the spherical silica was purchased from Qingdao ocean chemical Co., Ltd.

The analysis method in the examples of the present application is as follows: