Template agent and preparation method therefor and application thereof

[0055] In one embodiment of the present invention, the above-mentioned AEI-type silicon aluminum molecular sieve is prepared by the following preparation method, and the method includes the following steps:

[0056] 1) Preparing sol: mix template and alkali and water, then add Y-type molecular sieve and silicon source, and stir evenly at 25-45℃;

[0057] 2) Take the sol of step 1) and add 0.1-5wt% by weight (relative to the SiO in the silicon source 2 (Weight) seed crystals are added to the autoclave, stirred, and crystallized at 130-200°C for 5-10 days, wherein the stirring speed is 80-240 rpm.

[0058] In the present invention, the alkali is potassium hydroxide or sodium hydroxide.

[0059] In the present invention, the silicon source is selected from inorganic silicon. Preferably, it is silica-containing silica sol or solid silica gel for column chromatography.

[0060] In the present invention, the Y-type molecular sieve is used as an aluminum source.

[0061] In the present invention, products with different silicon content can be obtained by adjusting the amount of silicon source (such as silicon dioxide).

[0062] In the present invention, under the condition that the amount of template agent is close to the limit, normal crystallization is achieved by adding seed crystals, and the amount of seed crystals added is about the SiO in the silicon source. 2 0.1-5wt% by weight.

[0063] In the present invention, the product prepared by the above-mentioned reaction containing a high template agent is used as a seed crystal.

[0064] In the present invention, the silicon content of the molecular sieve directly affects the acidity of the molecular sieve and the catalytic activity of the catalyst.

[0065] In addition, in the present invention, inorganic silicon is used to replace organic silicon, which can smoothly realize the demand for scale-up production.

[0066] In the present invention, a pure AEI silica-alumina molecular sieve can be obtained with a certain amount of template and seed crystals.

[0067] As mentioned above, the preparation method of the present invention further includes the following steps:

[0068] i) Filter the product obtained in step 2) of the above-mentioned preparation method of AEI type silica-alumina molecular sieve, then wash with water, and then perform ammonium exchange or dilute acid solution for acid exchange with an aqueous solution of ammonium salt;

[0069] ii) subjecting the product of step i) to high temperature calcination;

[0070] iii) The calcined product of step ii) is acid exchanged with a dilute acid solution.

[0071] In the present invention, the weight ratio of the aqueous solution of the ammonium salt to the solid in the step i) is 1:5-15.

[0072] In the present invention, the ammonium salt in step i) is (NH4)nX, wherein X is sulfate, nitrate, chlorine, acetate or bicarbonate, and n is 1 or 2.

[0073] In the present invention, the ammonium exchange in the step i) is performed 3-5 times, preferably 4 times. Part of the ammonium and potassium ions can be exchanged through the ammonium exchange, and the exchange rate can reach 75-80%.

[0074] In the present invention, the weight ratio of the dilute acid aqueous solution to the solid in the step i) is 1:5-15.

[0075] In the present invention, the acid in step i) is selected from sulfuric acid, nitric acid, hydrochloric acid, acetic acid or carbonic acid.

[0076] In the present invention, the acid exchange in step i) is performed 3-5 times, preferably 4 times. Part of the acid and potassium ions can be exchanged through the acid exchange, and the exchange rate reaches 75-80%.

[0077] In the present invention, the calcination temperature in step ii) is 400-800°C.

[0078] In the present invention, the acid exchange in step iii) is performed 3-5 times, preferably 4 times. Through the acid exchange, partial acid and potassium ion exchange can be realized, and the exchange rate reaches 100%.

[0079] In the present invention, the acid in step iii) is selected from sulfuric acid, nitric acid, hydrochloric acid, acetic acid or carbonic acid.

[0080] In one embodiment of the present invention, the application of the above-mentioned AEI-type silica-alumina molecular sieve is also provided, which is used for the denitration of automobile exhaust gas of different kinds of diesel engines and petrochemical and chemical chemical industries. In addition to using the above-mentioned AEI silico-alumina molecular sieve as a catalyst for the purification of automobile exhaust, it is reported that the global annual demand for catalysts will increase by 6.0%. In 2012, the global catalyst market reached 16.3 billion US dollars and the output reached 5.3 million tons. After 2012, polymerization catalysts will grow the fastest. One of the reasons is the rapid economic growth in Africa/Middle East and Asia Pacific. Due to the steady increase in the demand for hydroprocessing catalysts and the high oil production in Africa/Middle East and Asia-Pacific regions, the demand for catalysts in the refining industry is also booming. The above-mentioned AEI silico-alumina molecular sieve of the present invention has excellent high and low-temperature hydrothermal stability, and is particularly suitable as a carrier of the above-mentioned catalyst, and therefore has broad applications in petrochemical and chemical industries. Since 1977, catalysts prepared from SAPO molecular sieves (MTO for short) have been used in the reaction of alcohols to olefins. Alcohols produced from coal cracking or natural gas can be used to generate olefins and propylene through MTO catalysts. Polyolefin materials are generated through polymerization, which can be processed into plastic products. It is estimated that in the next 5 years, China will form 12 million tons/year of MTO production capacity, and the annual consumption of catalysts will reach about 12,000 tons. Accordingly, the MTO catalyst market will exceed 2 billion yuan/year. By then, the demand for catalysts will far exceed the current domestic supply capacity. In this development process, catalyst suppliers will usher in good market opportunities. The above-mentioned AEI silico-alumina molecular sieve of the present invention is also particularly suitable as a carrier of the above-mentioned catalyst, and therefore has broad applications in petrochemical and chemical industries.

[0081] The present invention will be further described below in conjunction with specific implementation cases, but the present invention is not limited to the following implementation cases, and the methods are conventional methods unless otherwise specified. The materials can be obtained from open commercial channels unless otherwise specified.

[0082] Preparation Example 1 (Preparation of Template A)

[0083] Prepare template A through the following steps:

[0084] Using 2,6-dimethyl-piperidine as the starting reactant, adding potassium hydroxide ethanol solution to the bromoethane ethanol solution, the reaction occurs at room temperature to produce potassium bromide precipitation, and 1-ethyl-2 , 6-Dimethyl-piperidine. Concentrate and evaporate to get the product (molecular formula is C 9 H 19 N, marked as template A).

[0085] This step of the reaction is a method known to those skilled in the art and will not be repeated here.

[0086] Preparation Example 2 (Preparation of Template B)

[0087] Prepare template B through the following steps:

[0088] The product template A (100g, 98%, 0.70 mol) of Preparation Example 1 and 500ml of toluene solution of diethyl sulfate (180g, 98%, 1.14 mol) were reacted in a 2L reflux container at 110°C for 5-6 Hours, after cooling, the salt of 1,1-diethyl-2,6-dimethyl-piperidinium monoethyl sulfate precipitated out of the solution, and the white product was filtered to obtain 175.6g with a yield of 85% (molecular formula Is C 13 H 29 NSO 4 , Marked as template B).