A kind of titanium silicon molecular sieve and its synthesis method and application and a kind of method of cyclic ketone oxidation

Abstract

The invention relates to the field of catalytic materials and in particular provides a titanium silicalite molecular sieve, a preparation method and application of the titanium silicalite molecular sieve. The titanium silicalite molecular sieve is composed of the following elements: precious metals, silicon, titanium and oxygen, wherein the I960 / I550 value of the titanium silicalite molecular sieve is 0.5-0.9; the U480 / U330 value of the titanium silicalite molecular sieve is 0.5-5; and the N-117 / N-114 value of the titanium silicalite molecular sieve is 0.01-0.25. The invention further providesa cyclic ketone oxidation method. The cyclic ketone oxidation method comprises the following step: contacting cyclic ketone, an oxidizing agent and a catalyst, wherein the catalyst contains the titanium silicalite molecular sieve disclosed by the invention. Compared with the prior art, the titanium silicalite molecular sieve disclosed by the invention has the advantages that diffusion of the reactants and product is facilitated in an oxidation reaction, so that oxidative activity is fully achieved, and the selectivity is improved. For example, when applied to a reaction in which ring molecules, particularly cyclic ketone molecules, participate or are produced, the titanium silicalite molecular sieve can achieve excellent catalytic effects. Moreover, filtration and separation of the catalyst after the reaction can be further facilitated, and industrialized application is easily realized.

Description

technical field

[0001] The invention relates to a titanium-silicon molecular sieve, its synthesis method and application, and a method for oxidizing cyclic ketones. Background technique

[0002] Titanium-silicon molecular sieve is an important catalytic oxidation material. For example, titanium-silicon molecular sieve TS-1 with MFI crystal structure is a kind of transition metal element titanium introduced into the molecular sieve framework with ZSM-5 structure, which has excellent catalytic selective oxidation performance. A new type of titanium silicate molecular sieve. TS-1 not only has the catalytic oxidation effect of titanium, but also has the shape-selective effect and excellent stability of ZSM-5 molecular sieve. Since TS-1 molecular sieve can use non-polluting low-concentration hydrogen peroxide as an oxidant in the oxidation reaction of organic matter, it avoids the problems of complex oxidation process and environmental pollution, and has incomparable energy savi...

Examples

preparation example Construction

[0031]In the present invention, as long as the titanium-silicon molecular sieve has the aforementioned characteristics, the purpose of the present invention can be achieved, and its synthesis method can be various, as long as the titanium-silicon molecular sieve with the aforementioned characteristics can be synthesized. For the present invention, the titanium-silicon molecular sieve is preferably Silicon molecular sieves are synthesized as follows, the method comprising:

[0032] (1) mixing and contacting a precious metal source, an ammonia source, and optionally water to obtain a first mixture;

[0033] (2) In the presence of a templating agent, mixing the titanium source, the first mixture, and optionally water to obtain a second mixture;

[0034] (3) mixing the second mixture, an inorganic silicon source, and optionally water to obtain a third mixture;

[0035] (4) The third mixture is subjected to hydrothermal crystallization, and titanium-silicon molecular sieves are re...

Embodiment approach

[0042] According to a preferred embodiment of the present invention, the preferred stage (1) and stage (3) meet one or both of the following conditions:

[0043] Condition 1: the temperature of stage (1) is lower than the temperature of stage (3), preferably, the temperature of stage (1) is 10-50°C lower than the temperature of stage (3), preferably 20-40°C lower;

[0044] Condition 2: the time of stage (1) is less than the time of stage (3), preferably, the time of stage (1) is 5-24 hours shorter than the time of stage (3), preferably 6-12 hours shorter.

[0045] According to a preferred embodiment of the present invention, the temperature in stage (2) is lowered to not higher than 50°C, preferably 30-50°C, and the residence time is at least 1 hour, preferably 1-5h.

[0046] According to the method of the present invention, the heating rate and cooling rate for adjusting the temperature to the temperature of each stage can be selected according to the type of the reactor used...

Embodiment 1

[0094] (1) Mixing and contacting noble metal source palladium chloride and ammonia water (concentration is 20% by weight) to obtain a mixture; noble metal source: ammonia source (weight ratio)=2:20, solute content is 1% by weight, and the conditions for mixing and contacting include: 30°C, normal pressure, 4h;

[0095] (2) The mixture is then mixed with tetrabutyl titanate and tetrapropyl ammonium hydroxide;

[0096] (3) Then add silica gel, mix and carry out hydrothermal crystallization; silicon source: titanium source: precious metal source: templating agent: water (mol) = 100:2:1:15:1000;

[0097] Hydrothermal crystallization: go through the first stage at 140°C for 6 hours in a sealed reactor, then cool the mixture down to 30°C and experience the second stage for 2 hours, then continue to go through the third stage at a temperature of 170°C in a sealed reactor 12h (among them, the temperature rise rate from room temperature to the first stage temperature is 2°C / min, the t...

technical field

[0001] The invention relates to a titanium-silicon molecular sieve, its synthesis method and application, and a method for oxidizing cyclic ketones. Background technique

[0002] Titanium-silicon molecular sieve is an important catalytic oxidation material. For example, titanium-silicon molecular sieve TS-1 with MFI crystal structure is a kind of transition metal element titanium introduced into the molecular sieve framework with ZSM-5 structure, which has excellent catalytic selective oxidation performance. A new type of titanium silicate molecular sieve. TS-1 not only has the catalytic oxidation effect of titanium, but also has the shape-selective effect and excellent stability of ZSM-5 molecular sieve. Since TS-1 molecular sieve can use non-polluting low-concentration hydrogen peroxide as an oxidant in the oxidation reaction of organic matter, it avoids the problems of complex oxidation process and environmental pollution, and has incomparable energy savi...

Examples

preparation example Construction

[0031]In the present invention, as long as the titanium-silicon molecular sieve has the aforementioned characteristics, the purpose of the present invention can be achieved, and its synthesis method can be various, as long as the titanium-silicon molecular sieve with the aforementioned characteristics can be synthesized. For the present invention, the titanium-silicon molecular sieve is preferably Silicon molecular sieves are synthesized as follows, the method comprising:

[0032] (1) mixing and contacting a precious metal source, an ammonia source, and optionally water to obtain a first mixture;

[0033] (2) In the presence of a templating agent, mixing the titanium source, the first mixture, and optionally water to obtain a second mixture;

[0034] (3) mixing the second mixture, an inorganic silicon source, and optionally water to obtain a third mixture;

[0035] (4) The third mixture is subjected to hydrothermal crystallization, and titanium-silicon molecular sieves are re...

Embodiment approach

[0042] According to a preferred embodiment of the present invention, the preferred stage (1) and stage (3) meet one or both of the following conditions:

[0043] Condition 1: the temperature of stage (1) is lower than the temperature of stage (3), preferably, the temperature of stage (1) is 10-50°C lower than the temperature of stage (3), preferably 20-40°C lower;

[0044] Condition 2: the time of stage (1) is less than the time of stage (3), preferably, the time of stage (1) is 5-24 hours shorter than the time of stage (3), preferably 6-12 hours shorter.

[0045] According to a preferred embodiment of the present invention, the temperature in stage (2) is lowered to not higher than 50°C, preferably 30-50°C, and the residence time is at least 1 hour, preferably 1-5h.

[0046] According to the method of the present invention, the heating rate and cooling rate for adjusting the temperature to the temperature of each stage can be selected according to the type of the reactor used...

Embodiment 1

[0094] (1) Mixing and contacting noble metal source palladium chloride and ammonia water (concentration is 20% by weight) to obtain a mixture; noble metal source: ammonia source (weight ratio)=2:20, solute content is 1% by weight, and the conditions for mixing and contacting include: 30°C, normal pressure, 4h;

[0095] (2) The mixture is then mixed with tetrabutyl titanate and tetrapropyl ammonium hydroxide;

[0096] (3) Then add silica gel, mix and carry out hydrothermal crystallization; silicon source: titanium source: precious metal source: templating agent: water (mol) = 100:2:1:15:1000;

[0097] Hydrothermal crystallization: go through the first stage at 140°C for 6 hours in a sealed reactor, then cool the mixture down to 30°C and experience the second stage for 2 hours, then continue to go through the third stage at a temperature of 170°C in a sealed reactor 12h (among them, the temperature rise rate from room temperature to the first stage temperature is 2°C / min, the t...

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