CN103349975B - The activation method of 5A molecular sieve - Google Patents

Abstract

The invention discloses a kind of activation method of 5A molecular sieve, comprise the following steps: 1) 5A molecular sieve is put into clean without after the container of greasy dirt, put into activation furnace heat-activated together with container, control activation temperature at 300 ~ 360 DEG C, control soak time 5 ~ 7 hours; 2) to come out of the stove air cooling after cooling to the 5A molecular sieve after activation with the furnace 140 ~ 160 DEG C; 3) cooled 5A molecular sieve is placed in the sealing of dried nitrogen atmosphere to deposit.The present invention strictly controls activation process, optimize activation temperature, improve the activation efficiency of commercially available 5A molecular sieve, and then significantly add the adsorption capacity of 5A molecular sieve, make it meet requirement as cryogenic insulated cylinder adsorbent, thus improve the thermal insulation of cryogenic insulated cylinder; Excellent with the 5A molecular sieve performance after the inventive method activation, water absorption rate is high, and absorption property is stablized, and molecular sieve is not easily pulverized, and is realizing, under the prerequisite that 5A molecular sieve fully activates, reducing energy consumption.

Description

Activation method of 5A molecular sieve

technical field

The invention relates to an activation method of a molecular sieve, in particular to an activation method of a 5A molecular sieve.

Background technique

The material will slowly release the gas it absorbs or absorbs in a vacuum environment. In the low-temperature insulating gas cylinder, the hydrogen gas released by the material will reduce the vacuum degree of the vacuum interlayer and increase the heat transfer. Therefore, the high-vacuum low-temperature insulating gas 5A molecular sieve and palladium oxide are often used as adsorbents in the vacuum interlayer of the bottle. Among them, the hydrogen gas released by the palladium oxide adsorption material generates water, and the 5A molecular sieve is used to absorb water. At present, commercially available 5A molecular sieves generally need to be activated before they can be used normally. The commonly used activation method is to heat 5A molecular sieves to 250°C for 8 hours or to 550°C for 4 hours. The water absorption rate of the final molecular sieve is not more than 10%, and the activation is not sufficient, and the water absorption rate of the molecular sieve activated by the latter method is only 14%, and the activated 5A molecular sieve is fragile, and the activation effect directly affects the function of the 5A molecular sieve. realization. Therefore, it is extremely necessary to find out a method that can effectively activate 5A molecular sieves.

Contents of the invention

The purpose of the present invention is to provide a method for activating the 5A molecular sieve, which can increase the water absorption rate of the 5A molecular sieve so that the 5A molecular sieve can fully realize the adsorption function and meet the requirements of the cryogenic insulating gas cylinder adsorbent.

To achieve the above object, the technical solution adopted in the present invention is: a method for activating a 5A molecular sieve, the method comprising the following steps:

1) After putting the 5A molecular sieve into a clean and oil-free container, put it together with the container into the activation furnace for heating and activation, control the activation temperature at 300-360°C, and control the activation time for 5-7 hours;

2) Cool the activated 5A molecular sieve to 140-160°C with the furnace and then air-cool it;

3) Store the cooled 5A molecular sieve in a dry nitrogen atmosphere to prevent moisture in the air from being absorbed into the 5A molecular sieve.

Further, in the step 1), the activation time is controlled to be 345-355° C., and the activation time is controlled to be 5.5-6.5 hours.

Furthermore, in the step 2), the activated 5A molecular sieve is cooled to 145-155°C with the furnace and then air-cooled after being taken out of the furnace.

Preferably, in the step 1), the activation furnace is a muffle furnace.

Compared with prior art, the present invention has following advantage:

Firstly, the present invention strictly controls the activation process, optimizes the activation temperature, avoids the phenomenon in the prior art that the temperature is too low to affect the adsorption capacity of the molecular sieve, and the phenomenon that the temperature is too high destroys the crystal structure of the molecular sieve, and improves the activation efficiency of the commercially available 5A molecular sieve. Furthermore, the adsorption capacity of the 5A molecular sieve is greatly increased, so that it meets the requirements of being used as an adsorbent for low-temperature heat-insulating gas cylinders, thereby improving the heat insulation of low-temperature heat-insulating gas cylinders.

Second, the 5A molecular sieve activated by the method of the present invention has excellent performance, high water absorption, stable adsorption performance, the molecular sieve is not easy to be crushed, and the energy consumption is reduced under the premise of fully activating the 5A molecular sieve.

Detailed ways

The present invention will be further described below in conjunction with the examples, but the present invention is not limited to the following examples.

Example 1:

First, clean the tooling container used to hold the 5A molecular sieve and the sealed container for storing the 5A molecular sieve with acetone to remove oil; then, put 10kg of 5A molecular sieve into the clean tooling container and put it into the activation furnace for heating Activation, the activation furnace is a muffle furnace, the temperature in the activation furnace is controlled at 350°C, and the activation time is 6 hours. After the heating and activation is completed, it is cooled to 150°C with the furnace and then air-cooled; finally, the 5A molecular sieve after activation is treated with dry nitrogen The adsorbent is sealed and stored in a clean airtight container by 1kg per portion. Among them, the nitrogen seal is to use the nitrogen after liquid nitrogen gasification, and connect the outlet of the vaporizer of the low-temperature nitrogen bottle into a sealed container for nitrogen replacement.

After testing, the water absorption rate of the activated 5A molecular sieve is 19.5%.

Example 2

First, clean the tooling container used to hold the 5A molecular sieve and the sealed container for storing the 5A molecular sieve with acetone to remove oil; then, put 10kg of 5A molecular sieve into the clean tooling container and put it into the activation furnace for heating Activation, the temperature in the activation furnace is controlled at 300°C, and the activation time is 7 hours. After the heating and activation is completed, it is cooled to 140°C with the furnace and then air-cooled; finally, the activated 5A molecular sieve adsorbent is sealed in 1 kg with dry nitrogen. Store in a clean, airtight container.

After testing, the water absorption rate of the activated 5A molecular sieve is 19.0%.

Example 3

First, clean the tooling container used to hold the 5A molecular sieve and the sealed container for storing the 5A molecular sieve with acetone to remove oil; then, put 10kg of 5A molecular sieve into the clean tooling container and put it into the activation furnace for heating Activation, the temperature in the activation furnace is controlled at 360°C, and the activation time is 5.5 hours. After the heating and activation is completed, it is cooled to 160°C with the furnace and then air-cooled; finally, the activated 5A molecular sieve adsorbent is sealed in 1 kg with dry nitrogen. Store in a clean, airtight container.

After testing, the water absorption rate of the activated 5A molecular sieve is 19.3%.

Example 4

First, clean the tooling container used to hold the 5A molecular sieve and the sealed container for storing the 5A molecular sieve with acetone to remove oil; then, put 10kg of 5A molecular sieve into the clean tooling container and put it into the activation furnace for heating Activation, the temperature in the activation furnace is controlled at 345°C, and the activation time is 6.5 hours. After the heating and activation is completed, it is cooled to 155°C with the furnace and then air-cooled; finally, the activated 5A molecular sieve adsorbent is sealed in 1 kg with dry nitrogen. Store in a clean, airtight container.

After testing, the water absorption rate of the activated 5A molecular sieve is 20.3%.

Example 5

First, clean the tooling container used to hold the 5A molecular sieve and the sealed container for storing the 5A molecular sieve with acetone to remove oil; then, put 10kg of 5A molecular sieve into the clean tooling container and put it into the activation furnace for heating Activation, the temperature in the activation furnace is controlled at 355°C, and the activation time is 5 hours. After the heating and activation is completed, it is cooled to 145°C with the furnace and then air-cooled; finally, the activated 5A molecular sieve adsorbent is sealed in 1 kg with dry nitrogen. Store in a clean, airtight container.

After testing, the water absorption rate of the activated 5A molecular sieve is 19.6%.

Claims (3)

1. A method for activating a 5A molecular sieve for a low-temperature adiabatic adsorption bottle adsorbent, characterized in that: the method may further comprise the steps: 1) After putting the 5A molecular sieve into a clean and oil-free container, put it together with the container into the activation furnace for heating and activation, control the activation temperature at 355-360°C, and control the activation time for 5.5-6.5 hours; 2) Cool the activated 5A molecular sieve to 140-160°C with the furnace and then air-cool it; 3) Place the cooled 5A molecular sieve in a dry nitrogen atmosphere and seal it for storage to prevent moisture in the air from being absorbed into the 5A molecular sieve. 2. The method for activating the 5A molecular sieve used as an adsorbent in a low-temperature insulation adsorption bottle according to claim 1, characterized in that: in the step 2), the activated 5A molecular sieve is cooled to 145-155°C in the furnace and then air-cooled . 3. The method for activating the 5A molecular sieve used for the low-temperature heat-insulating adsorption bottle adsorbent according to claim 1 or 2, characterized in that: in the step 1), the activation furnace is a muffle furnace.