阅读说明：本技术 一种Ru-SSZ-13分子筛及其制备方法 (Ru-SSZ-13 molecular sieve and preparation method thereof ) 是由 胡晨晖 刘春红 范海东 杜凯敏 卓佐西 祁志福 陈亮 林贻超 于 2020-06-12 设计创作，主要内容包括：本发明涉及一种Ru-SSZ-13分子筛及其制备方法,包括：步骤1、将一定量浓度为0.001M～0.01M的Ru金属前驱体加入溶剂中,充分溶解后得到黑色溶液；步骤2、设定搅拌速率为100～500转/分钟,在搅拌条件下往步骤1所得黑色溶液中加入一定量的SSZ-13分子筛,并在25～80℃下持续搅拌2～24h进行离子交换反应,并通过过滤、离心和干燥获得黑色产物；步骤3、将步骤2得到的黑色产物按程序升温焙烧一定时间,得到Ru-SSZ-13分子筛。本发明的有益效果是：Ru是一种可变价金属元素,其价态可以从-2价连续变到+8价,所以Ru具有非常独特的性质；因此在SSZ-13晶体结构中引入Ru离子可潜在赋予SSZ-13一些独特且有待发掘的性质。(The invention relates to a Ru-SSZ-13 molecular sieve and a preparation method thereof, wherein the preparation method comprises the following steps: step 1, adding a certain amount of Ru metal precursor with the concentration of 0.001-0.01M into a solvent, and fully dissolving to obtain a black solution; step 2, setting the stirring speed to be 100-500 rpm, adding a certain amount of SSZ-13 molecular sieve into the black solution obtained in the step 1 under the stirring condition, continuously stirring for 2-24 hours at 25-80 ℃ for ion exchange reaction, and filtering, centrifuging and drying to obtain a black product; and 3, roasting the black product obtained in the step 2 for a certain time according to the programmed temperature rise to obtain the Ru-SSZ-13 molecular sieve. The invention has the beneficial effects that: ru is a variable valence metal element, and the valence state of the variable valence metal element can be continuously changed from-2 valence to +8 valence, so that Ru has very unique properties; the introduction of Ru ions in the SSZ-13 crystal structure can therefore potentially confer some unique and yet to be discovered properties to SSZ-13.)

1. A Ru-SSZ-13 molecular sieve, comprising: an SSZ-13 structure and trivalent Ru ions or Ru clusters located on the surface of the SSZ-13 structure; the SSZ-13 structure is made of AlO₄And SiO₄The tetrahedrons are connected end to end through oxygen atoms and are orderly arranged into an ellipsoidal cage with an eight-membered ring structure.

2. A method of preparing the Ru-SSZ-13 molecular sieve of claim 1, comprising the steps of:

step 1, adding a certain amount of Ru metal precursor with the concentration of 0.001-0.01M into a solvent, and fully dissolving to obtain a black solution;

step 2, setting the stirring speed to be 100-500 rpm, adding a certain amount of SSZ-13 molecular sieve into the black solution obtained in the step 1 under the stirring condition, continuously stirring for 2-24 hours at 25-80 ℃ for ion exchange reaction, and filtering, centrifuging and drying to obtain a black product;

and 3, roasting the black product obtained in the step 2 for a certain time according to the programmed temperature rise to obtain the Ru-SSZ-13 molecular sieve.

3. The method of claim 2 for the preparation of a Ru-SSZ-13 molecular sieve, wherein: in the step 1, the Ru metal precursor is ruthenium chloride and a hydrate thereof, ruthenium acetate and a hydrate thereof or ruthenium nitrate and a hydrate thereof.

4. The method of claim 2 for the preparation of a Ru-SSZ-13 molecular sieve, wherein: the solvent in the step 1 is water or methanol.

5. The method of claim 2 for the preparation of a Ru-SSZ-13 molecular sieve, wherein: in the step 2, the Si/Al ratio of the SSZ-13 molecular sieve is between 10 and 30.

6. The method of claim 2 for the preparation of a Ru-SSZ-13 molecular sieve, wherein: in the step 2, the stirring speed is 200 revolutions per minute, the stirring temperature is 25 ℃, and the stirring time is 12 hours.

7. The method of claim 2 for the preparation of a Ru-SSZ-13 molecular sieve, wherein: the temperature rise rate of the program in the step 3 is 1-10 ℃/min.

8. The method of claim 2 for the preparation of a Ru-SSZ-13 molecular sieve, wherein: the roasting temperature in the step 3 is within 300-450 ℃.

Technical Field

The invention relates to a novel Ru-SSZ-13 molecular sieve and a preparation method thereof.

Background

In recent years, with the rapid development of industry, the demand of molecular sieves in various industries has increased remarkably, and SSZ-13 molecular sieves have received extensive attention from academia and industry since the 20 th century 80 s, due to its unique pore structure, large specific surface area, good hydrothermal stability and shape-selective function, from Zones synthesis of Chevron (Chevron) corporation in the united states. SSZ-13 belongs to aluminosilicate molecular sieve, the framework of which is made of AlO₄And SiO₄The tetrahedrons are connected end to end through oxygen atoms and are orderly arranged into ellipsoidal Cages (CHA) with an eight-membered ring structure, and the windows of the cages are formed by connecting D6R units with four-membered rings to form a specific three-dimensional crossed channel structure. The internal dimension of the ellipsoidal cage topology is

Eight-membered ring window (channel)

Belongs to a small-pore zeolite molecular sieve in micropores. The specific surface area of the SSZ-13 molecular sieve is as high as 700m²The catalyst has a special ordered framework composition, has a developed pore structure and good thermal stability, and is an excellent adsorbent or catalyst carrier. In addition, Al- (OH) -Si bridge hydroxyl is formed at the oxygen atom connected with silicon and aluminum in the framework of the SSZ-13 molecular sieve, so that the SSZ-13 molecular sieve has certain acidity and cation exchange performance, and the SSZ-13 molecular sieve has good performances of acidity catalysis, shape-selective catalysis and the like. Based on the above properties, SSZ-13 molecular sieves are widely usedAmmonia selective catalytic reduction (NH)₃-SCR), Methanol To Olefins (MTO) and CO₂Adsorption separation and the like.

Fe-SSZ-13 molecular sieves, Cu-SSZ-13 molecular sieves and the like have been successfully prepared at present through cation exchange, however, Ru-SSZ-13 molecular sieves have not been reported yet.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a Ru-SSZ-13 molecular sieve and a preparation method thereof.

The Ru-SSZ-13 molecular sieve comprises: an SSZ-13 structure and trivalent Ru ions or Ru clusters located on the surface of the SSZ-13 structure; the SSZ-13 structure is made of AlO₄And SiO₄The tetrahedrons are connected end to end through oxygen atoms and are orderly arranged into an ellipsoidal cage with an eight-membered ring structure.

The preparation method of the Ru-SSZ-13 molecular sieve comprises the following steps:

step 1, adding a certain amount of Ru metal precursor with the concentration of 0.001-0.01M into a solvent, and fully dissolving to obtain a black solution;

step 2, setting the stirring speed to be 100-500 rpm, adding a certain amount of SSZ-13 molecular sieve into the black solution obtained in the step 1 under the stirring condition, continuously stirring for 2-24 hours at 25-80 ℃ for ion exchange reaction, and filtering, centrifuging and drying to obtain a black product;

and 3, roasting the black product obtained in the step 2 for a certain time according to the programmed temperature rise to obtain the Ru-SSZ-13 molecular sieve.

Preferably, in the step 1, the Ru metal precursor is ruthenium chloride and its hydrate, ruthenium acetate and its hydrate, or ruthenium nitrate and its hydrate.

Preferably, the solvent in step 1 is water or methanol (water is more preferred).

Preferably, the Si/Al ratio of the SSZ-13 molecular sieve in the step 2 is between 10 and 30.

Preferably, in the step 2, the stirring speed is 200 revolutions per minute, the stirring temperature is 25 ℃, and the stirring time is 12 hours.

Preferably, the temperature increase rate of the program in the step 3 is 1 ℃/min to 10 ℃/min (more preferably 5 ℃/min).

Preferably, the roasting temperature in the step 3 is within 300-450 ℃.

The invention has the beneficial effects that: ru is a variable valence metal element, and the valence state of the variable valence metal element can be continuously changed from-2 valence to +8 valence, so that Ru has very unique properties; the introduction of Ru ions in the SSZ-13 crystal structure can therefore potentially confer some unique and yet to be discovered properties to SSZ-13.

Drawings

FIG. 1 is an XRD spectrum of the prepared Ru-SSZ-13 molecular sieve;

FIG. 2 is a powder XRD spectrum of the Ru-SSZ-13 molecular sieve prepared in examples 1-4 of the invention;

FIG. 3 is an SEM and mapping image of the Ru-SSZ-13 molecular sieve prepared in example 1 of the invention.

Detailed Description

The present invention will be further described with reference to the following examples. The following examples are set forth merely to aid in the understanding of the invention. It should be noted that, for a person skilled in the art, several modifications can be made to the invention without departing from the principle of the invention, and these modifications and modifications also fall within the protection scope of the claims of the present invention.

The crystal structure of Ru-SSZ-13 comprises an SSZ-13 structure and trivalent Ru ions positioned on an eight-membered ring of the SSZ-13 structure; SSZ-13 is a molecular sieve having the CHA topology, which is formed from AlO₄And SiO₄The tetrahedrons are connected end to end through oxygen atoms and are orderly arranged into an ellipsoidal cage with an eight-membered ring structure. The preparation method comprises the following steps: dissolving a certain amount of Ru metal precursor in water to obtain a black solution, adding a certain amount of SSZ-13 molecular sieve under the condition of stirring, continuously stirring for a certain time, filtering, centrifuging and drying to obtain a black product, and finally roasting the black product at a programmed temperature to obtain the Ru-SSZ-13 molecular sieve.