CN104229821B - Beta Zeolite synthesis method - Google Patents

Abstract

The invention discloses a kind of Beta Zeolite synthesis method, comprise the steps: a), by soluble in water to aluminium source, template and sodium source, to be made into original solution; B) by above-mentioned original solution in 60～120 DEG C of activation processing 2～24 hours, obtain thermal activation solution; C) using granularity 20～1000 object silica gel particles as silicon source, silica gel is mixed with above-mentioned thermal activation solution, Silica Surface is soaked by thermal activation solution; D) Ludox after wetting keeps 24～48 hours in 120～180 DEG C of constant temperature, does crystallization processing; E), after crystallization is processed, separation of products, washing dry, calcination processing, obtain Beta zeolite product. Beta Zeolite synthesis method of the present invention, greatly reduces template consumption, simplifies processing step, a step crystallization, and crystallization time is only 1～2 day, and the physical and chemical performance such as silica alumina ratio, specific surface and the relative crystallinity of gained Beta molecular sieve obviously improves.

Description

Beta Zeolite synthesis method

Technical field

The present invention relates to crystal aluminosilicate Zeolite synthesis field, be specifically related to a kind of Beta Zeolite synthesis method.

Background technology

Beta molecular sieve is synthetic with classical hydrothermal crystallization method first in 1967 by Mobil company of the U.S.(US3308069). Due to its unique topological structure and good heat and hydrothermal stability, in alkylation, hydrocracking, face hydrogenThe aspects such as isomery, hydrofinishing, hydrocarbon cracking show excellent catalytic performance.

In common Beta Zeolite synthesis method, mostly the mixing of silicon source, aluminium source, sodium source, template and water will be containedThing is made slurries, in autoclave in 75～200 DEG C of crystallization 3～60 days.

US4847055 discloses a kind of improved Beta sieve technology, has used a kind of silicon source of particular size, syntheticIn system, use tetraethylammonium bromide as template, added crystal seed simultaneously. In the method crystallization process, easily generate mercerisingZeolite and ZSM-5 stray crystal, and tetraethylammonium bromide large usage quantity.

CN1108213A, CN1108214A disclose a kind of synthetic method of Beta molecular sieve, and the method is with 20～200 ordersSilica gel particle be silicon source, joined in the solution of aluminium source, NaOH, tetraethyl ammonium hydroxide and water composition, make siliconGlue particle surface is soaked by solution, crystallization 10～60 hours at 140～170 DEG C. Although the method has reduced templateConsumption, but still higher, TEA⁺/SiO₂=0.05～0.15。

CN1154341A discloses a kind of synthetic method of Beta molecular sieve, and the method is in CN1108214A mono-step crystallization methodOn basis, adopt two step crystallization methods, the method has further reduced template consumption, but still higher, TEA⁺/SiO₂=0.03～0.20。

Summary of the invention

The object of the present invention is to provide a kind of Beta Zeolite synthesis method, greatly reduce template consumption, simplifyProcessing step, a step crystallization, crystallization time is only 1～2 day, and the silica alumina ratio of gained Beta molecular sieve, specific surface and knot relativelyThe physical and chemical performances such as crystalline substance degree obviously improve.

For achieving the above object, technical scheme of the present invention is a kind of Beta Zeolite synthesis method of design, comprises as followsStep:

A) by soluble in water to aluminium source, template and sodium source, be made into original solution; Described template is tetraethyl hydroxideIn ammonium, tetraethylammonium bromide, etamon chloride and tetraethyl ammonium iodide one or more;

B) by above-mentioned original solution in 60～120 DEG C of activation processing 2～24 hours, obtain thermal activation solution;

C) using granularity 20～1000 object silica gel particles as silicon source, silica gel is mixed with above-mentioned thermal activation solution, makeSilica Surface is soaked by thermal activation solution;

D) Ludox after wetting keeps 24～48 hours in 120～180 DEG C of constant temperature, does crystallization processing; Described crystallization placeThe reaction system of reason has following mol ratio composition: SiO₂/Al₂O₃=20～600，Na₂O/SiO₂=0.01～0.1，TEA⁺/SiO₂=0.01～0.05，H₂O/SiO₂=2～5；

E), after crystallization is processed, separation of products, washing dry, calcination processing, obtain Beta zeolite product.

Preferably, described original solution was in 80～100 DEG C of activation processing 16～24 hours.

Preferably, described TEA⁺/SiO₂=0.01～0.25。

Preferably, described aluminium source is a kind of or several in sodium metaaluminate, hydrated alumina, boehmite and aluminium hydroxideKind.

Preferably, described sodium source is one or more in NaOH and sodium metaaluminate.

Preferably, the temperature of described crystallization processing is 140～160 DEG C.

Preferably, the granularity of described silica gel particle is 300～400 orders.

Beta Zeolite synthesis method step of the present invention b) in, the temperature and time of thermal activation treatment is for activated solution bodyBe most important, temperature is too low, and activation effect is poor, causes later stage template demand large, crystallization difficulty, and easily generate assortedPeak; Excess Temperature, equipment and maintenance cost significantly rise.

Beta Zeolite synthesis method step of the present invention d) in, the temperature and time of crystallization processing for generate degree of crystallinityHeight, the product that specific surface is high is most important, and crystallization temperature is too low, and because crystallization is incomplete, degree of crystallinity is lower, and specific surface is alsoLow; Crystallization temperature is too high, and Beta molecular sieve crystallinity reduces on the contrary.

Beta Zeolite synthesis method of the present invention, improves template (etamon to the synthetic method of existing molecular sieveIon TEA⁺) consumption obviously reduces, TEA⁺/SiO₂Minimumly reach 0.01, simplify processing step, a step crystallization, crystallization time is onlyIt is 1～2 day. Prepared Beta molecular sieve silica alumina ratio is high, and product silica alumina ratio approaches batching silica alumina ratio; Relative crystallinity is high, approximatelyBe 100～150%; Specific area is high, can reach 600m²/g。

Brief description of the drawings

Fig. 1 is the XRD crystalline phase characteristic pattern of comparative example of the present invention and embodiment gained Beta molecular sieve.

Detailed description of the invention

The method of the synthetic Beta molecular sieve of the present invention is as follows:

A) by soluble in water to aluminium source, template and sodium source, be made into original solution;

B), by above-mentioned original solution activation processing, obtain thermal activation solution;

C) using silica gel particle as silicon source, silica gel is mixed with above-mentioned thermal activation solution, making Silica Surface is thermal activationSolution soaks;

D) Ludox after wetting is done crystallization processing;

E), after crystallization is processed, separation of products, washing dry, calcination processing, obtain Beta zeolite product;

Wherein,

Described aluminium source can be one or more in sodium metaaluminate, hydrated alumina, boehmite and aluminium hydroxide;

Described template can be tetraethyl ammonium hydroxide, tetraethylammonium bromide, etamon chloride and tetraethyl iodateIn ammonium one or more;

Described sodium source can be one or more in NaOH and sodium metaaluminate;

The granularity of described silica gel particle is 20～1000 orders (being preferably 300～400 orders);

The temperature of described activation processing can be 60～120 DEG C, and the time can be (to be preferably 80～100 DEG C in 2～24 hoursActivation processing 16～24 hours);

The temperature of described crystallization processing can be 120～180 DEG C (being optimized for 140～160 DEG C), and the time can be 24～48Hour;

The reaction system of described crystallization processing has following mol ratio composition: SiO₂/Al₂O₃=20～600，Na₂O/SiO₂=0.01～0.1，TEA⁺/SiO₂=0.01～0.05(is optimized for 0.25～0.05), H₂O/SiO₂=2～5。

Below in conjunction with comparative example and embodiment, the specific embodiment of the present invention is further described. Following examplesOnly for technical scheme of the present invention is more clearly described, and can not limit the scope of the invention with this.

Comparative example l

Press the process of the synthetic Beta molecular sieve of CN1154341A, batching silica alumina ratio is 30.

Sodium metaaluminate (oxidation receive 55wt%, aluminium oxide 45wt%), the tetraethyl ammonium hydroxide aqueous solution (TEAOH, 25%) are addedEnter in deionized water, normal-temperature dissolution, stirs, and makes working solution; By silica gel (100～140 orders, igloss 6.5%) and upperState working solution and mix, make Ludox surface by working solution is soaked, obtain reactant mixture; Then by this reactant mixtureIn autoclave in 120 DEG C of crystallization 24 hours, then 140 DEG C of crystallization 48 hours; After crystallization is processed, separation of products, washingAnd in 120 DEG C dry, 550 DEG C of calcination processing, obtain Beta zeolite product. Raw material proportioning and physico-chemical parameter are in table 1. With this BetaMolecular sieve is as the primary standard substance (degree of crystallinity is 100%) of measuring relative crystallinity, and its XRD crystalline phase figure as shown in Figure 1.

Comparative example 2

The technique of synthetic Beta molecular sieve is identical with comparative example 1, and batching silica alumina ratio is 60.

Beta molecular sieve is synthesized according to the inventive method in EXAMPLE l～7:

A) by sodium metaaluminate (oxidation receive 55wt%, aluminium oxide 45wt%), the tetraethyl ammonium hydroxide aqueous solution (TEAOH,25%) add in deionized water, dissolve, stir, be made into original solution;

B) original solution is in the specified temp hydrothermal treatment consists some time, and parameter is in table 1;

C) silica gel (100～140 orders, igloss 6.5%) is mixed with above-mentioned working solution, make Ludox surface for workSolution soaks;

D) Ludox after wettability treatment is in 150 DEG C of crystallization 48h;

E) after crystallization is processed, separation of products, washing and in 120 DEG C dry, 550 DEG C of calcination processing, obtain Beta molecular sieve and produceProduct.

The XRD crystalline phase figure of the molecular sieve by embodiment 1～7 gained has Fig. 1 feature, illustrates that they are Beta moleculeSieve.

Table 1

Can find out that by table 1 temperature and time activating by the hydro-thermal of regulator solution can make synthetic Beta moleculeSieve template used dose and obviously reduce, crystallization time shortens, and the silica alumina ratio of Beta molecular sieve, degree of crystallinity and specific surface are obviously moreHigh.

Embodiment 8～13 synthesizes Beta molecular sieve according to the inventive method:

A) by sodium metaaluminate (oxidation receive 55wt%, aluminium oxide 45wt%), the tetraethyl ammonium hydroxide aqueous solution (TEAOH,25%) add in deionized water, dissolve, stir, be made into original solution;

B) original solution is in 100 DEG C of hydrothermal treatment consists 24h;

C) silica gel (200～300 orders, igloss 6.5%) is mixed with above-mentioned working solution, make Ludox surface for workSolution soaks;

D) Ludox after wettability treatment is in the specified temp crystallization some time, and parameter is in table 2;

E) after crystallization is processed, separation of products, washing and in 120 DEG C dry, 550 DEG C of calcination processing, obtain Beta molecular sieve and produceProduct.

The XRD crystalline phase figure of the molecular sieve by embodiment 8～13 gained has Fig. 1 feature, illustrates that they are Beta and divideSon sieve.

Table 2

Can find out by table 2, by the hydro-thermal activation of original solution, and the adjusting of crystallization temperature and time, syntheticTemplate used dose of obviously minimizing of Beta molecular sieve, crystallization time shortens, and not only degree of crystallinity and specific surface are high, and the sial of productHigher than obviously.

The above is only the preferred embodiment of the present invention, it should be pointed out that the ordinary skill people for the artMember, not departing under the prerequisite of the technology of the present invention principle, can also make some improvements and modifications, these improvements and modificationsAlso should be considered as protection scope of the present invention.

Claims (2)

1.Beta Zeolite synthesis method, is characterized in that, comprises the steps:

A) by soluble in water to aluminium source, template and sodium source, be made into original solution; Described template is tetraethyl ammonium hydroxide, fourIn ethyl ammonium bromide, etamon chloride and tetraethyl ammonium iodide one or more;

B) by above-mentioned original solution in 80～100 DEG C of activation processing 16～24 hours, obtain thermal activation solution;

C) using granularity 20～1000 object silica gel particles as silicon source, silica gel is mixed with above-mentioned thermal activation solution, make silica gelSurface is soaked by thermal activation solution;

D) silica gel after wetting keeps 24～48 hours in 120 DEG C of constant temperature, does crystallization processing; The reaction system of described crystallization processingThere is following mol ratio composition: SiO₂/Al₂O₃=20～600，Na₂O/SiO₂=0.01～0.1，TEA⁺/SiO₂=0.01～0.05，H₂O/SiO₂=2～5；

E), after crystallization is processed, separation of products, washing dry, calcination processing, obtain Beta zeolite product;

Wherein,

Described aluminium source is hydrated alumina or aluminium hydroxide;

Described sodium source is NaOH or sodium metaaluminate.

2. Beta Zeolite synthesis method according to claim 1, is characterized in that, the granularity of described silica gel particle is300～400 orders.