WO2016078035A1 - Active aluminosilicate material and preparation method therefor - Google Patents

Abstract

An active aluminosilicate material and a preparation method therefor, the preparation method comprising: kneading a natural Si-Al mineral raw material, an alkali metal hydroxide and water, performing extrusion forming, and performing sub-molten salt activation treatment at a temperature of 150^oC - 300^oC to obtain the active aluminosilicate material. The obtained active aluminosilicate material may act as a highly active Si-Al source for the synthesis of a zeolite. The preparation method reduces the requirements of an activation process with regard to a device, is simple and easy, and has low material consumption and low energy consumption. The "three wastes" are not discharged, and the Si-Al ratio of the product is adjustable.

Description

Active aluminosilicate material and preparation method thereof Technical field

The invention belongs to the field of comprehensive utilization of natural minerals, and relates to a living aluminosilicate material and a preparation method thereof, in particular to a method for preparing a living aluminosilicate material by extruding a natural silicon-aluminum mineral after being extruded by a sub-molten salt medium. The resulting activated aluminosilicate material can be used as a high activity silica aluminum source for the synthesis of molecular sieves.

Background technique

The molecular sieve is an aluminosilicate having a tetrahedral skeleton structure. The most basic structure constituting the zeolite skeleton is a silicon oxide (SiO ₄ ) tetrahedron and an aluminum oxide (AlO ₄ ) tetrahedron, which are mutually coupled by a common oxygen atom to form a three-dimensional network. The chemical structure of the structure is: Me _{x / n} [(AlO ₂ ) _x (SiO ₂ ) _y ] · mH ₂ O, where x, y represent the atomic number of Al and Si, and n is the metal ion Me valence , m is the number of water molecules. Due to its unique structure and properties, molecular sieves can be widely used in petrochemical and household chemical industries as main catalytic materials, adsorption separation materials and ion exchange materials.

The synthetic route of molecular sieves can be divided into two categories according to raw materials: synthesis using chemical raw materials and synthesis using natural clay. The silicon source and the aluminum source in the form of chemical raw materials are prepared from quartz and boehmite through complicated reaction and separation processes. The production process has long process route, high energy consumption and material consumption, and most processes have serious pollution discharge. Although the molecular sieve route based on inorganic chemical raw materials is mature, the technical conditions are easy to control, but the cost is high, and it is not a green synthetic route from its source. Therefore, in order to reduce the production cost of molecular sieves and achieve green synthesis, many researchers try to synthesize molecular sieves with natural clay with abundant raw materials and low prices, which not only can improve the utilization value of resources, greatly reduce the production cost, but also realize the green color of molecular sieve from the source. Synthesis, very promising.

However, although natural silicon-aluminum minerals are rich in a large amount of silicon-aluminum elements, the basic skeletons of these minerals are composed of silicon-oxygen polyhedrons and aluminoxy polyhedra in various ways. These polyhedrons are connected in a co-angled manner to form a stable The crystal structure of the frame, layer, chain, and ring island skeleton has low chemical reactivity, and the coexistence of silicon and aluminum in natural silicon-aluminum minerals is difficult to separate, so it is difficult to directly use such natural minerals for molecular sieves. Synthesis, but need to be activated.

At present, the most commonly used methods for the activation of natural minerals are high-temperature heat activation or alkali fusion activation. These activation methods have disadvantages such as high material consumption, high energy consumption, and poor activation effect, which limits their practical industrial applications. Therefore, whether the low energy consumption and low material consumption of natural silicon-aluminum minerals can be fully activated is the key to effectively utilizing natural silica-alumina mineral synthetic molecular sieves.

CN 103570032A discloses a preparation method of active aluminosilicate, in particular, the natural mineral is reacted in an alkali metal hydroxide solution having a concentration of more than 350 g/L at 150 to 300 ° C under a normal pressure open system. The reaction product is diluted with water to a pH of less than 10, and then separated by filtration to obtain an aqueous solution of an oligomeric high activity aluminosilicate and a reusable alkali metal hydroxide. In the activation process, the amount of water used is large, and the heat energy required for activation is high, and the obtained alkali metal hydroxide aqueous solution is concentrated and reused, and the energy consumption is high; the activation process is intermittent and the activated product is easily sticky. The wall is not easy to discharge. The above disadvantages limit the large-scale industrial application of the process.

Summary of the invention

It is an object of the present invention to provide a simple and easy way to activate natural silica-alumina minerals as a raw material for synthesizing molecular sieves, thereby reducing energy consumption and material consumption.

Another object of the present invention is to provide a living aluminosilicate material prepared according to the activation method which can be used as a highly active silicon aluminum source for synthesizing molecular sieves.

Another object of the present invention is to provide the use of the active aluminosilicate material in the preparation of molecular sieves.

In order to achieve the above object, in one aspect, the present invention provides a method for preparing a reactive aluminosilicate material, the method comprising:

The natural silicoalumina mineral raw material, the alkali metal hydroxide is mixed with water and extruded, and then activated by a sub-molten salt at a temperature of 150 to 300 ° C to obtain a living aluminosilicate material.

The purpose of the extrusion molding in the invention is mainly to reduce the contact area with the reactor by using the fluffy structure between the dry strips, reduce the stickiness and reduce the heat energy required for evaporating water, and realize continuous production. According to a specific embodiment of the present invention, in the extrusion molding process of the present invention, the natural silicon-aluminum mineral, the alkali metal hydroxide and the water are first weighed according to a certain ratio, and the kneading is carried out and the extrusion type and size of the extrusion machine are controlled to be different. Shapes (column, trefoil, four-leaf, etc.) and wet strips of diameter. In the present invention, the diameter of the extruded strip is preferably in the range of 0.5 mm to 10 mm, and the natural silica-alumina mineral can be effectively activated, and more preferably, the extruded strip has a diameter of 1 mm to 6 mm. In the present invention, the length of the strip obtained by the extruded strip has no significant influence on the subsequent activation performance, and the present invention does not impose special requirements on the length of the strip, and can be determined according to the scale of the heating vessel when the extruder and the subsequent sub-molten salt are activated. . The gap between the strips is favorable for the heat transfer process during activation. The present invention can accelerate the activation reaction rate by kneading the raw materials, and the aluminosilicate in the natural ore is fully activated, and the activated silicon is formed by extrusion molding. The aluminate has a content of active SiO ₂ and active Al ₂ O ₃ of 99% by weight or more, respectively. In a more specific embodiment of the invention, the content of active SiO ₂ and active Al ₂ O ₃ can even reach 99.5 wt. %the above.

According to a specific embodiment of the present invention, in the preparation method of the active aluminosilicate of the present invention, the wet strip after extrusion molding is activated at a temperature of 150 ° C to 300 ° C under a normal pressure open system, usually, the activation process It is 0.5 to 8 h, preferably 0.5 to 4 h. According to a specific embodiment of the present invention, the specific activation time in the present invention may be determined by the moisture added during the extrusion process, and the amount of water required for different natural silicoalusite or different alkali contents may be different, so that the activation time may be different. Drying to complete drying can be extended for a period of time, and prolonging the time after complete activation will not substantially increase or decrease the product properties.

According to a particular embodiment of the invention, the method of preparing a reactive aluminosilicate material of the invention may further comprise the step of pulverizing the activated treated strip to produce a powdered activating product.

According to a specific embodiment of the present invention, in the method for preparing a reactive aluminosilicate material of the present invention, the natural silica-alumina mineral material may include feldspar, nepheline, leucite, beryl, muscovite, and pyrophyllite. , kaolinite, rectorite, jadeite, spodumene, diaspore, perlite, cordierite, phlogopite, vermiculite, montmorillonite, talc, serpentine, illite, palygorskite, sea foam One or more of stone, attapulgite, enstatite, diopside, amphibole, and olivine. More specifically, according to the needs of the silicon-aluminum ratio in the target activation product, a plurality of natural silicon-aluminum mineral raw material ratios can be adjusted to achieve an adjustable silicon-aluminum ratio of the product.

According to a specific embodiment of the present invention, in the method for preparing a reactive aluminosilicate material of the present invention, the content of silicon aluminum in the natural silicon-aluminum mineral raw material is ≥70% by weight based on silicon oxide and alumina, and the particle diameter is less than or equal to 20 mesh. .

According to a specific embodiment of the present invention, in the method for producing a reactive aluminosilicate material of the present invention, the alkali metal hydroxide is selected from one or more of lithium hydroxide, sodium hydroxide, and potassium hydroxide.

According to a specific embodiment of the present invention, in the method for preparing a reactive aluminosilicate material of the present invention, the molar amount of the alkali metal hydroxide is 0.5 to 6 times the total molar amount of silicon aluminum in the natural silicoalumino mineral raw material, preferably 1 to 4 times.

According to a specific embodiment of the present invention, in the method for producing a reactive aluminosilicate material of the present invention, the molar amount of water is from 0.3 to 2.5 times, preferably from 0.5 to 2.0 times, the molar content of silicon aluminum in the natural silicon-aluminum mineral raw material.

According to a specific embodiment of the present invention, in the method for preparing a reactive aluminosilicate material aluminosilicate material of the present invention, the molar amount of water is 0.1 to 1.8 times, preferably 0.3 to 1.5, the molar amount of the alkali metal oxide. Times.

In the present invention, the amount of water used for control is favorable for achieving high-efficiency activation, and the wet strip extruded by the extruder can be ensured to have sufficient hardness so as not to soften into a block and stick to the wall during activation, and to avoid mass transfer. The process affects the final activation effect because there is too little water.

According to a specific embodiment of the present invention, a method for preparing a reactive aluminosilicate material of the present invention comprises the steps of:

(1) Preparation: According to the total amount of silicon aluminum in the natural silicon-aluminum mineral (n(Si)+n(Al)): the molar amount of alkali metal hydroxide: the molar amount of water = 1: (0.5 ~ 6): ( a ratio of 0.3 to 2.5), weighing natural silicon-aluminum mineral raw materials, alkali metal hydroxides and water;

(2) Extrusion molding: the weighed natural silicon-aluminum mineral raw material (pre-pulverized natural silica-alumina mineral to a 20-mesh sieve, preferably 100 mesh sieve) and alkali metal hydroxide are stirred and mixed, and then added as needed The amount of water is kneaded and extruded on a extruder to obtain a wet strip of the mixture;

(3) activation of the sub-molten salt: the wet strip of the mixture formed by extruding the strip is placed in a high-temperature oven, heated to 150 ° C to 300 ° C, and reacted under a normal pressure open system for 0.5 to 4 h, and a strip-shaped activator is obtained after the reaction is completed;

(4) Crushing: Further, the strip-shaped activator obtained in the step (3) can be pulverized to obtain a powdery active aluminosilicate material.

In the method of the invention, the mineral extrusion strip is firstly formed and then activated by the sub-molten salt medium, the process is simple and easy, the requirements of the activation process on the equipment are reduced, the operation is easy, and the natural mineral is large-volume and continuous. Activation, and compared with the prior art, the water usage and energy consumption of the activation process are reduced, and the crystal structure of the mineral can be sufficiently destroyed, and the activated silicon aluminum material has a high content of active silicon aluminum, which can be used as a silicon aluminum source. Used in the synthesis of molecular sieves.

In another aspect, the invention also provides a reactive aluminosilicate material which is prepared in accordance with the preparation process of the invention as previously described. The main component of the active aluminosilicate material of the present invention is an oligomeric aluminosilicate. It has been found that the content of active SiO ₂ and Al ₂ O ₃ in the active aluminosilicate material of the invention can reach 99 wt% or more, respectively, and the active aluminosilicate material can replace the silicon-aluminum source of the conventional inorganic chemical product, especially It can be used as a highly active silicon aluminum source for the synthesis of molecular sieves.

In another aspect, the invention also provides for the use of said reactive aluminosilicate materials, particularly for their use in the preparation of molecular sieves. Specifically, the active aluminosilicate material prepared by the invention can replace the inorganic chemical reagents such as silica sol, water glass and aluminum sulfate as the starting silicon aluminum source raw material of the synthetic molecular sieve, for example, for preparing A, X, Y, ZSM-5, beta aluminosilicate molecular sieves, etc. That is, the present invention also provides a preparation point A method of sub-screening comprising: preparing a living aluminosilicate material according to the preparation method of the present invention; and preparing a molecular sieve using the active aluminosilicate material as a source of silicon aluminum.

The invention has the following beneficial effects:

The activation method provided by the invention has simple process flow, reduces the requirements of the activation process on the equipment, is easy to operate, has low energy consumption, high mineral utilization rate, high added value of products, no “three wastes” emission, low cost, wide source of raw materials, and products. The silicon-aluminum ratio is adjustable for easy implementation. The main activated product of the invention is a strip-shaped oligomeric high-activity aluminosilicate which can be further pulverized to obtain a powdery product, and is easy to store and transport, and is advantageous for industrial large-scale applications. The activated product of the present invention can replace the conventional inorganic chemical product silicon aluminum source, for example, a silicon aluminum material which can be synthesized as a molecular sieve.

DRAWINGS

1 is a schematic flow chart of a method for preparing a reactive aluminosilicate material of the present invention;

2 is an XRD spectrum of the molecular sieve obtained in Example 1;

Figure 3 is an SEM image of the molecular sieve obtained in Example 1;

4 is an XRD spectrum of the molecular sieve obtained in Example 2;

Figure 5 is an SEM image of the molecular sieve obtained in Example 2;

6 is an XRD spectrum of the molecular sieve obtained in Example 3;

Figure 7 is an SEM image of the molecular sieve obtained in Example 3;

Figure 8 is a XRD spectrum of the molecular sieve obtained in Example 4;

Figure 9 is a SEM spectrum of the molecular sieve obtained in Example 4;

Figure 10 is a graph showing the content of active SiO ₂ and Al ₂ O ₃ obtained by activation of different extruded strips in Example 5;

Figure 11 is a XRD spectrum of the molecular sieve obtained by activation of different extruded strips in Example 5;

Fig. 12 is a SEM spectrum of the molecular sieve obtained in Example 5 when the diameters of the extruded strips were 1 mm, 2 mm, 4 mm and 6 mm, respectively.

detailed description

The invention is further illustrated by the following examples and the accompanying drawings, which are intended to illustrate the embodiments and features of the invention.

As shown in Fig. 1, the activation methods in the examples are basically carried out as follows: the natural silicon-aluminum mineral raw material, the alkali metal hydroxide and the water are kneaded and squeezed, and the sub-molten salt is activated to obtain high activity. The aluminosilicate dry strip is further pulverized to obtain a raw material for synthesizing the molecular sieve.

The active SiO ₂ content and the active Al ₂ O ₃ content in the mineral are defined as SiO ₂ and Al ₂ O ₃ (Wei B., Liu H formed in the activation process which can be extracted by acid or alkali and used as a raw material for molecular sieve synthesis. Li T., Cao L., Fan Y., Bao X. AIChE Journal; 2010, 56(11), 2913-2922).

The content of active SiO ₂ and active Al ₂ O ₃ mentioned in the examples is determined by the following method: 4 g of the activated product is weighed into a beaker, and 100 mL of a 4 mol/L HCl solution is added and stirred at room temperature for 2 h, after the reaction is completed. The solution was filtered, and the content of active SiO ₂ and active Al ₂ O _{3 in the} liquid phase was analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES). The content of active SiO ₂ and active Al ₂ O ₃ contained in the sample is calculated as follows:

Example 1

The natural silica-alumina mineral used in this embodiment is natural rector soil (produced by Hubei Celebrity Rectori Co., Ltd., particle size less than 100 mesh), the Al ₂ O ₃ content in the mineral is 38.2 wt.%, and the SiO ₂ content is 41.3 wt. .%; The alkali metal hydroxide used in this example is sodium hydroxide.

(1) Weigh the material: according to the total amount of silicon and aluminum in the natural rector soil (n(Si)+n(Al)): the molar amount of sodium hydroxide: the molar amount of water is 1:3:2, weigh the Soil, sodium hydroxide and water, specifically weigh 100g of the soil, weigh 127.5g of sodium hydroxide, weigh 38.3g of water.

(2) Extrusion molding: firstly crush the natural rector soil weighed in step (1) and mix it with sodium hydroxide, then add the required water for kneading, and finally extrude the strip on the twin-screw extruder. , a 1.8 mm diameter cylindrical mixture wet strip was obtained.

(3) Activation of the sub-molten salt: The wet strip of the mixture formed by the step (2) is placed in a high-temperature oven, then heated to 260 ° C, and reacted in an atmospheric open system for 4 h, and a strip-shaped activated product is obtained after the reaction is completed.

(4) Molecular sieve synthesis: The strip-shaped activated product obtained in the step (3) is pulverized (the pulverization particle size depends on the type of the synthetic molecular sieve) to obtain a highly active oligomeric aluminosilicate powder. The content of active SiO ₂ and active Al ₂ O ₃ in the obtained active aluminosilicate material sample was determined to be 99.3 wt.% and 99.7 wt.%, respectively.

Preparation of directing agent: 24 g of sodium hydroxide solid particles (Beijing Chemical Plant, purity 99%) was dissolved in 32.2 g of water, and cooled to room temperature for use. 26.7 g of aluminum sulfate (molecular formula: Al ₂ (SO ₄ ) ₃ ·18H ₂ O, Beijing Yili Fine Chemicals Co., Ltd., purity 99%) was dissolved in 32.2 g of water, and cooled to room temperature for use. The prepared aluminum sulfate solution is added to a sodium hydroxide solution to prepare a high alkalinity sodium metaaluminate solution. 96.6g sodium silicate (molecular formula: Na ₂ SiO ₃ ·9H ₂ O, Tianjin Jinke Fine Chemical Research Institute, purity 99%) was dissolved in 105.7g water, and 51.5g silica sol (Qingdao Ocean Chemical Co., Ltd., SiO) was added. ₂ content 30.3%, Na ₂ O content 0.06%), rapid stirring for 3h, then drip into the high alkalinity sodium metasilicate solution, mix well, stir and aging at 35 ° C for 4h, in the 25 ° C incubator for 2 days after the system The desired structure directing agent is obtained.

Synthesis of NaY molecular sieve: Weigh 4.5g of activated silica-alumina material powder, 1.1g of sodium hydroxide solid particles, 7g of heat-activated diatomaceous earth (SiO ₂ content 93.6wt.%) at 600°C, 7g of structure directing agent, and 45g Ionized water is mixed and stirred. After reacting at 60 ° C for 12 h, the mixture was poured into a stainless steel reaction vessel lined with tetrafluoroethylene and heated to 100 ° C for 24 h. After the end of the crystallization, the crystallized product was cooled, filtered and diluted to a pH of less than 10, and dried at 110 ° C overnight to obtain a crystallized product, the XRD spectrum of which is shown in FIG. The XRD spectrum of the product showed characteristic diffraction peaks of Y-type molecular sieves at 2θ angles of 15.7°, 18.7°, 20.4°, 23.7°, 27.1°, 30.8°, 31.5° and 34.2°, indicating that the product was a Y-type molecular sieve. The SEM image of the molecular sieve is shown in Fig. 3. As can be seen from the figure, the product is mostly normal octahedral crystal grains of about 500 nm, and the morphology is regular and the size is relatively uniform.

Example 2

The natural silica-alumina mineral used in this embodiment is natural kaolin (produced by China Kaolin Company, having a particle size of less than 300 mesh), and the mineral contains Al ₂ O ₃ 44.2 wt.% and contains SiO ₂ 52.7 wt.%. The alkali metal hydroxide used in this example is sodium hydroxide.

(1) Weighing materials: According to the total amount of silicon and aluminum in natural kaolin (n(Si)+n(Al)): sodium hydroxide molar amount: water molar amount is 1:2.5:1.8 weighed kaolin, sodium hydroxide And water, specifically, 120 g of kaolin was weighed, 157.4 g of sodium hydroxide was weighed, and 51 g of water was weighed.

(2) Extrusion molding: firstly mix and mix the natural kaolin and sodium hydroxide weighed in step (1), then add the required water for kneading, and finally extrude the strip on the extruder to obtain 1.5 mm diameter three. Leaf rhombic mixture wet strip.

(3) Activation of the sub-molten salt: The wet strip of the mixture formed by the step (2) is placed in a high-temperature oven, then heated to 200 ° C, and reacted in an atmospheric open system for 4 h, and a strip-shaped activated product is obtained after the reaction is completed.

(4) Molecular sieve synthesis: The strip-shaped activated product obtained in the step (3) is pulverized to obtain a highly active oligomeric aluminosilicate powder. The content of active SiO ₂ and active Al ₂ O ₃ in the obtained active aluminosilicate material sample was determined to be 99.6 wt.% and 99.8 wt.%, respectively.

Preparation of the directing agent: same as in Example 1.

Synthesis of NaY molecular sieve: Weigh 4.0g of activated product powder, 0.85g of sodium hydroxide solid particles, 5.8g of heat-activated diatomaceous earth (SiO ₂ content 93.6wt.%) at 600°C, 6.2g of structure-directing agent, and 40g Ionized water is mixed and stirred. After reacting at 60 ° C for 12 h, the mixture was poured into a stainless steel reaction vessel lined with polytetrafluoroethylene and heated to 100 ° C for 24 h. After the end of the crystallization, the crystallized product was cooled, filtered and diluted to a pH of less than 10, and dried at 110 ° C overnight to obtain a crystallized product, the XRD spectrum of which is shown in FIG. The XRD spectrum of the product showed characteristic peaks of the Y-type molecular sieve, indicating that the product was a pure Y-type molecular sieve without crystals. The SEM image of the molecular sieve is shown in Fig. 5. As can be seen from the figure, the product is mostly aggregated 200-500 nm regular octahedral crystal.

Example 3

The natural silica-alumina mineral used in this embodiment is natural perlite (produced by Liaoning Jianping, having a particle size of less than 20 mesh), and the mineral contains 13.3 wt.% of Al ₂ O _{3 and} 76.2 wt.% of SiO ₂ . The alkali metal hydroxide used in this example is sodium hydroxide.

(1) Weigh the material: according to the total amount of silicon aluminum in the natural perlite (n(Si)+n(Al)): sodium hydroxide molar amount: the molar amount of water is 1:3.5:2, weigh the perlite, alkali Metal hydroxide and water, specifically weigh 80g of perlite, weigh 156.9g of sodium hydroxide, weighed 40.3g of water.

(2) Extrusion molding: firstly crush the natural perlite weighed in step (1) and mix it with sodium hydroxide, then add the required water for kneading, and finally extrude the strip on a twin-screw extruder. A 1.8 mm diameter trilobal columnar mixture wet strip was obtained.

(3) Activation of the sub-molten salt: The wet strip of the mixture formed by the step (2) is placed in a high-temperature oven, then heated to 250 ° C, and reacted in an atmospheric open system for 3 h, and a strip-shaped activated product is obtained after completion of the reaction.

(4) Molecular sieve synthesis: The strip-shaped activated product obtained in the step (3) is pulverized to obtain a highly active oligomeric aluminosilicate powder. The content of active SiO ₂ and active Al ₂ O ₃ in the obtained active aluminosilicate material sample was determined to be 99.2 wt.% and 99.7 wt.%, respectively.

Synthesis of ZSM-5 molecular sieve: Weigh 3.8g of activated product powder, 2.0g of sodium hydroxide solid particles, 55.4g of heat activated diatomaceous earth (SiO ₂ content 93.6wt.%) at 600°C, tetrapropylammonium bromide 20.5 g, mixed with 500g of deionized water and stirred. After reacting at 70 ° C for 2 h, the mixture was poured into a stainless steel reaction vessel lined with polytetrafluoroethylene and heated to 170 ° C for 48 h. After the end of the crystallization, the crystallized product was cooled, filtered and diluted to a pH of less than 10, and dried at 110 ° C overnight to obtain a crystallized product, the XRD spectrum of which is shown in FIG. The XRD spectrum of the product has a five-finger peak characteristic of ZSM-5 type molecular sieve at a 2θ angle of 22.5° to 25°, indicating that the product is a ZSM-5 type molecular sieve. The SEM image of the molecular sieve is shown in Fig. 7. As can be seen from the figure, the product is a spherical shape of about 5 to 7 μm in the form of a rectangular parallelepiped, and no impurity crystals appear.

Example 4

The natural silica-alumina mineral used in this embodiment is natural kaolin (produced by China Kaolin Company, having a particle size of less than 300 mesh), and the mineral contains Al ₂ O ₃ 44.2 wt.% and contains SiO ₂ 52.7 wt.%. Natural illite (produced by Liaoning Jianping, particle size less than 100 mesh), mineral containing Al ₂ O ₃ 24.8 wt.%, containing SiO ₂ 60.9 wt.%. The alkali metal hydroxide used in this example is sodium hydroxide.

(1) Weigh the material: according to the molar total of mixed natural minerals (n(Si)+n(Al)): sodium hydroxide molar amount: water molar ratio 1:3.3:2 weighed kaolin, illite, hydrogen Sodium oxide and water, specifically 40 g of kaolin, 40 g of illite, 171.4 g of sodium hydroxide, and 46.7 g of water were weighed.

(2) Extrusion molding: firstly crush the natural kaolin and illite weighed in step (1) and mix with sodium hydroxide, then add the required water for kneading, and finally extrude the strip on the twin-screw extruder. Molding gave a wet strip of 2.0 mm diameter cylindrical mixture.

(3) Activation of sub-molten salt: The wet strip of the mixture formed by the step (2) is placed in a high-temperature oven, then heated to 250 ° C, and reacted under a normal pressure open system for 3 h, and a strip-shaped activated product is obtained after the reaction is completed.

(4) Molecular sieve synthesis: The strip-shaped activated product obtained in the step (3) is pulverized to obtain a highly active oligomeric aluminosilicate powder. The content of active SiO ₂ and active Al ₂ O ₃ in the obtained active aluminosilicate material sample was determined to be 99.2 wt.% and 99.9 wt.%, respectively.

Preparation of the directing agent: same as in Example 1.

Synthesis of NaY molecular sieve: Weigh 4.8g of activated product powder, 1.6g of sodium hydroxide solid particles, 5.2g of heat-activated diatomaceous earth (SiO ₂ content 93.6wt.%) at 600°C, 7.6g of structure directing agent, and 50g Ionized water is mixed and stirred. After reacting at 60 ° C for 12 h, the mixture was poured into a stainless steel reaction vessel lined with polytetrafluoroethylene and heated to 100 ° C for 24 h. After the end of the crystallization, the crystallized product was cooled, filtered and diluted to a pH of less than 10, and dried at 110 ° C overnight to obtain a crystallized product, the XRD spectrum of which is shown in FIG. The XRD spectrum of the product has a characteristic peak of a Y-type molecular sieve, indicating that the product is a pure phase Y-type molecular sieve with few heterocrystals. The SEM image of the molecular sieve is shown in Fig. 9. As can be seen from the figure, the product is a regular octahedral grain of about 500 to 700 nm, and the morphology is regular and slightly aggregated.

Example 5

The natural silica-alumina mineral used in this embodiment is natural kaolin (produced by China Kaolin Company, having a particle size of less than 300 mesh), and the mineral contains Al ₂ O ₃ 44.2 wt.% and contains SiO ₂ 52.7 wt.%. The alkali metal hydroxide used in this example is sodium hydroxide.

(1) Weighing materials: According to the total amount of silicon and aluminum in natural kaolin (n(Si)+n(Al)): sodium hydroxide molar amount: water molar amount is 1:2.0:1.5 weighed kaolin, sodium hydroxide And water, specifically weigh 120g of kaolin, weigh 125.9g of sodium hydroxide, weighed 42.5g of water.

(2) Extrusion molding: firstly pulverize the natural kaolin weighed in step (1) and mix it with sodium hydroxide, then add the required water for kneading, and finally extrude the strip on the twin-screw extruder, respectively A wet strip of cylindrical mixture of 1.0, 1.5, 2.0, 3.0, 4.0, 5.0, 6.0 mm diameter was obtained.

(3) activation of sub-molten salt: the wet strip of the mixture formed by the step (2) is placed in a high-temperature oven, then heated to 250 ° C, and reacted under a normal pressure open system for 2.5 h, and the respective strips are obtained after the reaction is completed. Activated product.

(4) Molecular sieve synthesis: The strip-shaped activated product obtained in the step (3) is pulverized to obtain a highly active oligomeric aluminosilicate powder. It is determined that the content of active SiO ₂ and active Al ₂ O ₃ in the obtained sample of active aluminosilicate material is shown in FIG. 10 , and it can be seen from FIG. 10 that the content of active SiO ₂ is about 99.5%, and the content of active Al ₂ O _{3 is} Both are about 99.5%, and the same natural minerals have about the same activation effect at different extrusion diameters.

Synthesis of NaA molecular sieve: 5.8 g of activated powder of different diameters were weighed and mixed with 32 g of deionized water, respectively. After reacting at 70 ° C for 4 h, the mixture was poured into a stainless steel reaction vessel lined with polytetrafluoroethylene and heated to 90 ° C for 6 h. After the end of the crystallization, the crystallized product was cooled, filtered and diluted to a pH of less than 10, and dried at 100 ° C overnight to obtain a crystallized product, the respective XRD patterns of which are shown in FIG. As can be seen from Figure 11, the XRD spectra of the product are 7.3°, 10.2°, 12.5°, 16.2°, 21.8°, 24.1°, 27.2°, 30.0°, 34.3°, which are characteristic peaks of type A molecular sieves, indicating the product. For pure phase A molecular sieves with few heterocrystals, the crystallinity of each product is concentrated between 95% and 97%.

The SEM image of the molecular sieve obtained by the extrusion strips of the present embodiment having diameters of 1 mm, 2 mm, 4 mm, and 6 mm, respectively, is shown in Fig. 12. As can be seen from the figure, the A synthesized by the activation of the diameter of the extruded strips of 1, 2, 4, and 6 mm The appearance of the molecular sieves is not much different, and they are regular cubic crystal grains of about 1000 nm, and the corners are right angles.

Claims (16)

1. A method for preparing a reactive aluminosilicate material, the method comprising:

   The natural silicoalumina mineral raw material, alkali metal hydroxide and water are kneaded and extruded, and then activated at a temperature of 150 to 300 ° C to obtain a living aluminosilicate material.
2. The method according to claim 1, further comprising the step of pulverizing the activated strip to obtain a powdery activated product.
3. The preparation method according to claim 1, wherein the natural silica-alumina mineral raw material comprises feldspar, nepheline, leucite, beryl, muscovite, pyrophyllite, kaolinite, rectorite, jadeite, Spodumene, diaspore, perlite, cordierite, phlogopite, vermiculite, montmorillonite, talc, serpentine, illite, palygorskite, sepiolite, attapulgite, eclogite, translucent One or more of stone, amphibole, and olivine.
4. The production method according to claim 1 or 3, wherein the natural silica-alumina mineral raw material has a silicon-aluminum content of ≥ 70% by weight based on silicon oxide and alumina, and a particle diameter of 20 mesh or less.
5. The production method according to claim 1, wherein the alkali metal hydroxide is one or more selected from the group consisting of lithium hydroxide, sodium hydroxide, and potassium hydroxide.
6. The production method according to claim 1 or 5, wherein the molar amount of the alkali metal hydroxide is 0.5 to 6 times, preferably 1 to 4 times, the total amount of the silicon aluminum in the natural silicoalumino mineral raw material.
7. The process according to claim 1, wherein the molar amount of water is from 0.3 to 2.5 times, preferably from 0.5 to 2.0 times, the molar content of silicon aluminum in the natural silicoalumino mineral raw material.
8. The process according to claim 1, wherein the amount of water used is from 0.1 to 1.8 times, preferably from 0.3 to 1.5 times, the molar amount of the alkali metal oxide.
9. The preparation method according to claim 1 or 7 or 8, wherein the total amount of silicon aluminum in the natural silicoalumino mineral (n(Si) + n(Al)): alkali metal hydroxide molar amount: molar amount of water = 1: (0.5 to 6): (0.3 to 2.5).
10. The preparation method according to claim 1, wherein the extruded strip has a shape of one or more of a cylinder, a trefoil column, and a four-leaf column.
11. The production method according to claim 1, wherein the extruded strip has a diameter of 0.5 mm to 10 mm, preferably 1 mm to 6 mm.
12. The preparation method according to claim 1, wherein the wet strip after the extrusion molding is activated at a temperature of 150 ° C to 300 ° C under a normal pressure open system.
13. The production method according to claim 1 or 12, wherein the activation process is 0.5 to 8 hours, preferably 0.5 to 4 hours.
14. A reactive aluminosilicate material prepared by the preparation method according to any one of claims 1 to 13.
15. A method of preparing a molecular sieve, the method comprising:

    Preparing an active aluminosilicate material according to the preparation method according to any one of claims 1 to 13;

    The molecular sieve is prepared using the activated aluminosilicate material as a source of silicon aluminum.
16. The method according to claim 15, wherein the molecular sieve is an A, X, Y, ZSM-5 or beta type silica alumina molecular sieve.

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