CN100445196C - Carbon nanotube hydrogen storage and its coating method - Google Patents

Abstract

The present invention relates to a carbon nanometer tube hydrogen storing and coating method which comprises a hydrogen storing part and a coating part. The purification, the washing operation, the drying operation and the shearing and preprocessing operation are carried out, and then, a coating medium is conveyed to a coating tank. A carbon nanometer tube is conveyed to a hydrogen storing tank for the hydrogen storage of the carbon nanometer tube. The carbon nanometer tube after hydrogen storage is driven by airflow, and the carbon nanometer tube enters the coating tank through a pressure valve for coating a hydrogen storage carbon nanometer tube. After the coating operation is completed, a blow off valve is opened, and thus, the coating tank is returned to normal pressure. The coated hydrogen storage carbon nanometer tube is taken, namely that a coated hydrogen storage carbon nanometer tube in a dry state is obtained. The present invention realizes the purposes of the high pressure hydrogen storage and the normal pressure transportation of the carbon nanometer tube. The hydrogen storage amount of the carbon nanometer tube can be accurately calculated relatively, thereby, the double verification purpose is achieved. The present invention is suitable for the absorption and the coating operation of nanometer materials, submicron materials and micrometer materials. The coated hydrogen storage carbon nanometer tube can be used as beneficial compensation energy sources of propellant in solid rocket propellant or gun powder, and can be also used for energy source batteries.

Description

Carbon nanotube hydrogen storage and its coating method

a technical field

The invention relates to a nano material hydrogen storage and coating technology after hydrogen storage, in particular to a carbon nanotube hydrogen storage and coating method.

Two background technology

Hydrogen energy is an inexhaustible renewable clean energy, but the storage and transportation of hydrogen energy is an important factor restricting the utilization of hydrogen energy. At present, the main methods of hydrogen energy storage and transportation are: liquefaction storage and transportation method, compressed storage and transportation method, solid hydrogen-liquid hydrogen mixed storage and transportation method, metal hydride storage and transportation method, organic liquid hydride hydrogen storage, inorganic compound hydrogen storage, activated carbon adsorption hydrogen storage, etc. These hydrogen storage methods all have low mass hydrogen storage capacity (about 2%wt-3%wt), which cannot meet the requirements of power energy use.

In recent years, with the continuous deepening of research on carbon nanotubes, the broad application prospects of carbon nanotubes in hydrogen energy storage and transportation are increasingly revealed. Scientists at home and abroad have conducted extensive research on the hydrogen storage performance of carbon nanotubes. According to data reports , carbon nanotubes can store hydrogen at a maximum of 10%wt-12%wt, and the minimum is only about 3%wt-5%wt. However, carbon nanotubes are generally used as a carrier of hydrogen energy under high pressure. When the system pressure is reduced or released, the hydrogen adsorbed in the carbon nanotubes will be partially or mostly desorbed, which is not conducive to the accurate measurement of the hydrogen storage of the carbon nanotubes. Stable storage and utilization of hydrogen energy.

At present, the research on hydrogen storage of carbon nanotubes still stays in the basic theory of hydrogen storage capacity and hydrogen storage mechanism. As for how the hydrogen storage carbon nanotubes can continue to store hydrogen stably in the carbon nanotubes for a long time after the system is depressurized. In the middle but not outside, there is no literature report.

In order to solve the above problems, the current practice is to calculate the amount of hydrogen absorbed by carbon nanotubes by using the decrease in system pressure during the hydrogen absorption process of carbon nanotubes and the volume of liquid displaced during hydrogen release, or to calculate the amount of hydrogen absorbed by carbon nanotubes after hydrogen absorption. The weight change was used to calculate the amount of hydrogen adsorbed. Of these two methods, the former is greatly affected by the ambient temperature, and the latter is greatly affected by the system pressure. It can neither accurately calculate the amount of hydrogen absorbed by carbon nanotubes nor solve the problem of hydrogen energy storage under normal pressure.

Three invention content

The object of the present invention is to provide a method for coating the hydrogen-storage carbon nanotubes while the carbon nanotubes are hydrogen-storing, so as to prevent the hydrogen energy from the hydrogen-storage carbon nanotubes from escaping after the system is depressurized. Carbon nanotube hydrogen storage and its coating method.

The technical solution for realizing the purpose of the present invention is: a carbon nanotube hydrogen storage and coating method thereof, including two parts of hydrogen storage and coating, the process flow and operating conditions are carried out in the following manner: first pretreatment: carbon nanotube Carry out purification, washing, drying, shearing, and dispersion without destroying the structure of carbon nanotubes during shearing; vacuum treatment: the hydrogen storage tank and the coating tank are evacuated separately, and then the coating medium is sent into the coating tank, and the carbon The nanotubes are sent into the hydrogen storage tank; then the hydrogen storage is processed; the pressure valve is closed, the hydrogen intake valve is adjusted, and the carbon nanotubes are stored for hydrogen; coating treatment; the pressure valve is opened, and the carbon nanotubes after hydrogen storage are driven by the airflow , into the coating tank through the pressure valve. When the system pressure is balanced, close the pressure valve and use alcohol or benzene coating medium to coat the hydrogen storage carbon nanotubes. After the coating is completed, open the release valve to restore the coating tank. At normal pressure, the coated hydrogen storage carbon nanotubes are taken out, and the coated hydrogen storage carbon nanotubes in a dry state are obtained after the alcohol or benzene volatilizes.

In the carbon nanotube hydrogen storage and coating method thereof of the present invention, after the pretreated carbon nanotubes store hydrogen under high pressure, the coating treatment of the hydrogen storage carbon nanotubes is directly carried out without pressure relief and separation treatment, so as to prevent storage Hydrogen escapes.

In the carbon nanotube hydrogen storage and coating method thereof of the present invention, microwave dispersion is used for pretreatment.

The hydrogen storage pressure of the carbon nanotube hydrogen storage and the coating method thereof of the present invention is 8-12 MPa.

The coating time of the carbon nanotube hydrogen storage and coating method thereof of the present invention is 30-60 minutes.

The principle of the invention is the wettability of carbon nanotubes to alcohol and benzene, and the self-volatility of alcohol and benzene. When the carbon nanotubes after hydrogen storage are mixed with alcohol or benzene solution, the surface of carbon nanotubes has strong wetting and adsorption properties for alcohol and benzene, so that the alcohol or benzene inorganic salt solution is coated on the carbon nanotubes. On the surface and both ends of the tube, when the system is depressurized, alcohol or benzene volatilizes in the atmosphere, while inorganic salts remain on the surface and both ends of the carbon nanotubes, hindering the escape of hydrogen.

Compared with the prior art, the present invention has the following significant advantages: 1. The purpose of high-pressure hydrogen storage and atmospheric pressure transportation of carbon nanotubes is realized; 2. The hydrogen storage capacity of carbon nanotubes can be calculated more accurately, It can not only calculate the hydrogen storage capacity of the coated carbon nanotubes, but also calculate the hydrogen storage capacity of the carbon nanotubes by reducing the system pressure, so as to achieve the purpose of double verification, which is beneficial to the long-term stable hydrogen storage of carbon nanotubes and Carry out in-depth and meticulous research on the hydrogen storage performance of carbon nanotubes; 3. This method is applicable to the adsorption and coating of all nano, submicron and micron materials; 4. The coated hydrogen storage carbon nanotubes can be used as propellant Beneficial supplemental energy is used in solid rocket propellants or gunpowder, and can also be used in energy cells.

Four drawings

Fig. 1 is a process flow diagram of the carbon nanotube hydrogen storage and coating method of the present invention.

Fig. 2 is a schematic diagram of the device for carbon nanotube hydrogen storage and its coating method of the present invention.

Five specific implementation methods

The present invention will be further described below in conjunction with the accompanying drawings.

In conjunction with Fig. 1, Fig. 2, a kind of embodiment of the present invention is:

The first step: pretreatment of carbon nanotubes, including purification, washing, drying, shearing and dispersion of carbon nanotubes;

The second step: observe the pressure gauge 3 and pressure gauge 6, check the air tightness of the system, and prevent the system from being poorly connected;

The third step: close valve 2, relief valve 5, pressure valve 9 and three-way valve 7, and relief valve 5 and feeding valve on hydrogen storage tank 8 and coating tank, and open the vacuum on hydrogen storage tank and coating tank respectively The valve evacuates the system;

Step 4: open the feed valve on the hydrogen storage tank 8 and quickly add carbon nanotubes to the hydrogen storage tank and close the feed valve; open the feed valve on the coating tank to quickly add the coating agent and close the feed valve;

Step 5: Open the valve 2 and the three-way valve 7, and carry out the hydrogen storage experiment of carbon nanotubes until the specified time is reached;

Step 6: After the hydrogen storage experiment is over, open the pressure valve 9, the carbon nanotubes enter the coating tank 10 driven by the air flow, close the pressure valve 9, valve 2 and hydrogen gas 1, and carry out the coating of the carbon nanotubes after hydrogen storage. Repeat experiment;

Step 7: After the coating experiment is over, open the release valve 5 and the release valve on the hydrogen storage tank 8 and the coating tank 10 to release residual hydrogen;

Step 8: Close the hydrogen valve to end the experiment.

Claims (5)

1, a kind of hydrogen Storage in Carbon Nanotubes and method for coating thereof comprise Chu Qing and coat two parts, and technical process and operational condition are carried out in the following manner:

1.1 pre-treatment: carbon nanotube carries out purifying, washing, drying, shearing, dispersion, the structure of destroying carbon nanometer tube not during shearing;

1.2 vacuum-treat: hydrogen container and coating jar are evacuated respectively, will coat medium then and send into the coating jar, and carbon nanotube is sent into hydrogen container;

1.3 storage hydrogen: the closing presure valve, the air intake valve of adjusting hydrogen carries out hydrogen Storage in Carbon Nanotubes;

1.4 coating: open pressure valve, the carbon nanotube behind the storage hydrogen enters the coating jar through pressure valve under air-flow drives, after the system pressure balance, and the closing presure valve, the coating medium of use alcohol or benzene stores up the hydrogen carbon nanotube and coats;

1.5 after coating end, open and diffuse valve, make to coat a jar recovery normal pressure;

1.6 the storage hydrogen carbon nanotube after take out coating treats promptly to get after the volatilization of alcohol or benzene the storage hydrogen carbon nanotube after the coating of drying regime.

2, a kind of hydrogen Storage in Carbon Nanotubes according to claim 1 and method for coating thereof, after it is characterized in that pretreated carbon nanotube under high pressure stores up hydrogen, directly store up the coating of hydrogen carbon nanotube without the release separating treatment and handle, prevent that the hydrogen of storing from escaping.

3, hydrogen Storage in Carbon Nanotubes according to claim 1 and 2 and method for coating thereof adopt microwave to disperse when it is characterized in that pre-treatment.

4, hydrogen Storage in Carbon Nanotubes according to claim 1 and 2 and method for coating thereof is characterized in that storing up hydrogen pressure at 8～12MPa.

5, hydrogen Storage in Carbon Nanotubes according to claim 1 and 2 and method for coating thereof is characterized in that the coating time was at 30～60 minutes.

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