CN-122006669-A - Hydrogen adsorbent, granulating and temperature-pressure double-control activating method thereof and multi-tower continuous hydrogen production system

Abstract

The invention discloses a hydrogen adsorbent, a granulating and temperature-pressure double-control activating method thereof and a multi-tower continuous hydrogen production system. According to the invention, foam blocking of the adsorbent powder is realized by bonding the alloy powder and the foam auxiliary material, and the operation mode of coating the breathable high-temperature-resistant film is adopted, so that pulverization and cracking in hydrogen adsorption-desorption circulation are effectively inhibited, and according to tests, the adsorbent coated by foam blocking-particles is obviously improved in the effective use cycle times compared with the common extrusion or disc-granulated alloy adsorbent, and the adsorption capacity attenuation capacity in the later stage of circulation is effectively reduced.

Inventors

• LI SHUANG
• SHI YIXIANG
• WANG YURUI
• LIN QING
• CAI NINGSHENG

Assignees

• 清华大学

Dates

Publication Date

20260512

Application Date

20260210

Claims (10)

1. 1. A hydrogen adsorbent comprising: The spherical soft material comprises alloy powder and foam auxiliary materials, wherein the alloy powder and the foam auxiliary materials are bonded through an adhesive, and the alloy powder is La x Ni y M z series rare earth alloy adsorbent; The breathable high-temperature-resistant film is coated on the outer surface of the spherical soft material.
2. 2. The hydrogen adsorbent according to claim 1, wherein the volume ratio of the alloy powder to the foam auxiliary material is 1 (0.1-1.0); And/or the mass ratio of the alloy powder to the adhesive is 100 (4-12).
3. 3. The hydrogen adsorbent of claim 1, wherein the foam auxiliary material has a particle size of 10-100 μm and an open cell content of 90% or more, and comprises at least one of polyimide foam and silicone rubber open cell foam.
4. 4. The hydrogen adsorbent of claim 1 wherein the binder comprises at least one of cyanoacrylate glue, epoxy resin, cycloruff resin, poly cool resin, phenolic resin, polyester resin, and drunk acid resin.
5. 5. The hydrogen adsorbent of claim 1 wherein the gas permeable, high temperature resistant membrane comprises a lofted polytetrafluoroethylene membrane.
6. 6. A method for granulating a hydrogen adsorbent, which is used for preparing the hydrogen adsorbent according to any one of claims 1 to 5, and comprises the following steps: (1) Mixing alloy powder, foam auxiliary material and adhesive on a disc granulating machine uniformly, and rolling the materials into spherical soft materials by virtue of centrifugal force and gravity, wherein the particle size of the spherical soft materials is 1-10mm; (2) Spraying and introducing an expanded polytetrafluoroethylene (ePTFE) membrane to coat the outer surface; (3) Drying to obtain adsorbent particles.
7. 7. A temperature and pressure double control activation method for a hydrogen adsorbent, which is characterized by being applicable to the hydrogen adsorbent according to any one of claims 1-5, and comprising the following steps: (a) The temperature gradient impurity removal is carried out by sequentially carrying out low-temperature dehydration treatment, medium-temperature impurity removal treatment and high-temperature activation treatment on the hydrogen adsorbent; (b) And the pressure circulation stress release is that the hydrogen adsorbent is subjected to 100-200 times of high-low pressure circulation between normal pressure and 0.4-2 MPa, and the residual stress in the adsorbent is released.
8. 8. The temperature and pressure double control activation method according to claim 7, wherein the low temperature dehydration treatment is to remove water adsorbed on the surface of the adsorbent and in the pore canal by heat preservation for 0.5-2 hours at 80-100 ℃; And/or the medium-temperature impurity removal treatment is to remove impurity gas by heat preservation for 1-2 hours at the temperature of 140-180 ℃; And/or the high-temperature activation treatment is to keep the temperature at the temperature of more than 180 ℃ for 1-2 hours.
9. 9. The temperature and pressure dual control activation method according to claim 7, wherein the single high and low pressure cycle in step (b) comprises: the hydrogen adsorbent is boosted from normal pressure to high pressure of 0.4-2 MPa, and is kept under the high pressure for 1-30 min, wherein the boosting time is 0.1-5 min; and (3) pressing the hydrogen adsorbent from high pressure to normal pressure, and maintaining the pressure for 1-10 min under the normal pressure to complete one cycle, wherein the pressure reduction time is 1-5 min.
10. 10. The multi-tower continuous hydrogen production system is characterized by comprising at least two adsorption towers, wherein the adsorption towers are filled with the hydrogen adsorbent according to any one of claims 1-5, and when at least one adsorption tower performs the temperature-pressure double-control activation process according to any one of claims 7-9, the rest adsorption towers perform selective adsorption on hydrogen in hydrogen-containing mixed gas so as to achieve the aim of purifying hydrogen.

Description

Hydrogen adsorbent, granulating and temperature-pressure double-control activating method thereof and multi-tower continuous hydrogen production system Technical Field The invention relates to the technical field of hydrogen energy preparation, in particular to a hydrogen adsorbent, a granulating and temperature-pressure double-control activating method thereof and a multi-tower continuous hydrogen production system. Background La xNiyMz and other rare earth alloys are materials with excellent hydrogen selective adsorption performance in the normal temperature to medium temperature range, can directly rely on vacuumizing for desorption in an adsorption temperature range through selective adsorption of hydrogen in mixed gas, do not need additional heating for auxiliary desorption, and obtain more pure hydrogen with more than 99% after desorption, and directly realize direct adsorption and enrichment of hydrogen in one step. The method is particularly suitable for industrial gas sources with low hydrogen content (such as 5% -30%), such as pipeline network hydrogen-doped gas, steel Gao Luqi hydrogen extraction and other application scenes. However, in the practical application process, the rare earth alloy hydrogen adsorbent has two key problems, and the long-term stable use of the rare earth alloy hydrogen adsorbent is severely restricted. On the one hand, the problem of poisoning of impurities is that in typical application scenes such as pipe network hydrogen doping, blast furnace gas in the steel industry and the like, hydrogen-containing mixed gas contains impurity gases with different contents such as H 2 S, CO and the like, and the impurities can react with La xNiyMz series rare earth alloy to cause poisoning of the adsorbent, so that the adsorbent loses the selective adsorption capability on hydrogen. On the other hand, the problems of cyclic pulverization and adsorption capacity attenuation are that the LaNi 5 -based adsorbent (which is a typical representative of La xNiyMz series rare earth alloy) can generate obvious volume change in the hydrogen adsorption-desorption cycle process, the LaNi 5 -based adsorbent is converted into corresponding hydride during adsorption, the volume is increased by about 20%, and the volume is reduced during desorption. In the repeated circulation process, residual stress can be generated in the crystal, and the LaNi 5 -based adsorbent can be pulverized due to continuous accumulation of the stress, if the adsorbent is formed, a cracking phenomenon can be directly generated, and finally the serious cracking of the adsorbent is caused, the adsorption capacity is obviously reduced, and the industrial requirement of long-term hydrogen purification cannot be met. Disclosure of Invention The present invention aims to solve at least one of the technical problems in the related art to some extent. In order to overcome the defects of the prior art, the invention provides a hydrogen adsorbent, a granulating and temperature-pressure dual-control activating method thereof and a multi-tower continuous hydrogen production system, wherein foam isolation among adsorbent particles is realized by utilizing disc granulation, and the problem of cracking of a formed adsorbent caused by volume change of adsorbent powder due to lattice cyclic stress, which is formed by hydrogen adsorption-hydrogen desorption multi-cycle, can be restrained by cooperation with outer layer thin-wall cladding, and an in-situ activating means for reducing the hydrogen adsorption capacity of the adsorbent due to cyclic stress after multi-cycle is provided. The method lays a technical foundation for crushing and pulverizing the formed direct adsorbent for inhibiting hydrogen, prolonging the service life of the direct adsorbent, and realizing multi-tower-wheel-change continuous hydrogen production. Therefore, the invention provides a hydrogen adsorbent, a granulating and temperature-pressure double-control activating method thereof and a multi-tower continuous hydrogen production system. In a first aspect, the present invention provides a hydrogen adsorbent comprising: The spherical soft material comprises alloy powder and foam auxiliary materials, wherein the alloy powder and the foam auxiliary materials are bonded through an adhesive, and the alloy powder is La xNiyMz series rare earth alloy adsorbent; The breathable high-temperature-resistant film is coated on the outer surface of the spherical soft material. Further, the volume ratio of the alloy powder to the foam auxiliary material is 1 (0.1-1.0). Further, the mass ratio of the alloy powder to the adhesive is 100 (4-12). Further, the particle size of the foam auxiliary material is 10-100 mu m, and the aperture ratio is more than 90%. Further, the foam auxiliary material comprises at least one of polyimide foam and silicone rubber open-cell foam. Further, the adhesive comprises at least one of cyanoacrylate glue, epoxy resin, cyclic soft resin, poly cool resin,