CN-122028975-A - Adsorbent material, adsorption system and adsorption process

Abstract

The adsorbent material for Pressure Swing Adsorption (PSA) related processes may provide an improved purification process in which the temperature difference between the adsorption and desorption processes of the adsorbent material bed is reduced. Embodiments may be configured such that the adsorbent material has occluded micropores or macropores. In some embodiments, the occlusion of the micropores or macropores may be up to 42% of the micropores of the adsorbent material. At least one metal acetate may be used for occlusion of micropores or macropores. Surprisingly, it was found that the use of an adsorbent material with occluded micro-or macropores increases the yield for purification of the product gas despite occlusion of the micro-or macropores.

Inventors

• T.C. GORDON
• M. Hartmann, grace
• THOMS MARTIN
• R.D. Whitley
• G.C.Liu
• J.R. Hufton
• W.J. Castill Jr.
• Virbhadra S.J.

Assignees

• 气体产品与化学公司

Dates

Publication Date

20260512

Application Date

20241031

Priority Date

20231103

Claims (20)

1. 1. An adsorber for an adsorption system, the adsorber comprising: a vessel positionable to receive a fluid to purify the fluid, the vessel having a bed of adsorbent material; the adsorbent material bed includes a first layer of adsorbent material having a small portion of micropores occluded by at least one salt consisting of a metal cation and an anion comprising carbon (C), hydrogen (H), and oxygen (O), a small portion of macropores occluded by the at least one salt, a small portion of mesopores and macropores occluded by the at least one salt, or a small portion of micropores, mesopores, and macropores occluded by the at least one salt.
2. 2. The adsorber of claim 1 wherein the at least one salt is at least one metal acetate and the first layer of adsorbent material has the small portion of micropores occluded by the at least one metal acetate less than 42% and greater than 8% of the occluded micropores of the adsorbent material of the first layer of adsorbent material.
3. 3. The adsorber of claim 1 wherein the at least one salt is at least one metal acetate and the first layer of adsorbent material has the small portion of macropores occluded by the at least one metal acetate less than 20% by volume and greater than or equal to 2% by volume of the occluded macropores of the adsorbent material of the first layer of adsorbent material.
4. 4. The adsorber of claim 2 wherein the at least one metal acetate salt is potassium acetate or barium acetate.
5. 5. The adsorber of claim 1 wherein the at least one salt is at least one metal acetate and the first layer of adsorbent material has the small portion of micropores occluded by the at least one metal acetate less than 42% by volume and greater than or equal to 3% by volume of the occluded micropores of the adsorbent material of the first layer of adsorbent material.
6. 6. The adsorber of claim 1 wherein the at least one salt is at least one metal acetate and the first layer of adsorbent material has the small portion of macropores occluded by the at least one metal acetate, wherein the small portion of macropores occluded by the at least one metal acetate is less than 15% by volume and greater than or equal to 3% by volume of the occluded macropores of the adsorbent material of the first layer of adsorbent material.
7. 7. The adsorber of claim 1 wherein the fraction occluded is between 0.03 cc/g and 0.15 cc/g of the micropores are occluded.
8. 8. The adsorber of claim 1 wherein the bed of adsorbent material comprises a second layer of adsorbent material.
9. 9. A pressure swing adsorption system, the pressure swing adsorption system comprising: a vessel positionable to receive a fluid to purify the fluid, the vessel having a bed of adsorbent material; the adsorbent material bed includes a first layer of adsorbent material having a small portion of micropores occluded by at least one salt consisting of a metal cation and an anion comprising carbon (C), hydrogen (H), and oxygen (O), a small portion of macropores occluded by the at least one salt, a small portion of mesopores and macropores occluded by the at least one salt, or a small portion of micropores, mesopores, and macropores occluded by the at least one salt.
10. 10. The system of claim 9, wherein the at least one salt is at least one metal acetate and the first layer of adsorbent material has the small portion of micropores occluded by the at least one metal acetate less than 42% by volume and greater than 8% by volume of the occluded micropores of the adsorbent material of the first layer of adsorbent material.
11. 11. The system of claim 9, wherein the at least one salt is at least one metal acetate salt and the first layer of adsorbent material has the small portion of macropores occluded by the at least one metal acetate salt less than 20% by volume and greater than or equal to 2% by volume of the occluded macropores of the adsorbent material of the first layer of adsorbent material.
12. 12. The system of claim 10, wherein the at least one metal acetate is potassium acetate or barium acetate.
13. 13. A method for preparing an adsorbent material for adsorption processing, the method comprising: exposing the solid particulate adsorbent material to a first salt solution for a preselected period of time for occluding a small portion of the micropores of the adsorbent material with at least one salt of the first salt solution, the at least one salt of the first salt solution comprising at least one salt consisting of a metal cation and an anion comprising carbon (C), hydrogen (H), and oxygen (O), and Drying the adsorbent material.
14. 14. The method of claim 13, wherein the small portion of micropores of the adsorbent material occluded by the at least one salt of the first salt solution are less than or equal to 20% and greater than or equal to 2% of the occluded micropores of the adsorbent material.
15. 15. The method according to claim 13, the method comprising: the solid particulate adsorbent material is removed from the salt solution.
16. 16. The method of claim 13, wherein the first salt solution is a first metal acetate solution and the at least one salt of the first salt solution comprises a first metal acetate, the method further comprising: exposing the solid particulate adsorbent material to a second salt solution comprising a second metal acetate for a preselected period of time for occluding a small portion of the micropores of the adsorbent material with the second metal acetate; Heating the sorbent material after exposure to the first salt solution and the second salt solution to convert the first metal acetate to a first metal carbonate and the second metal acetate to a second metal carbonate; The sorbent material is washed to remove the first metal carbonate from the sorbent material and to facilitate positioning of the second metal carbonate in a small portion of the macropores of the sorbent material.
17. 17. The method of claim 16, wherein the small portion of macropores of the sorbent material occluded by the second metal acetate are less than or equal to 20% by volume of the occluded macropores of the sorbent material, and are greater than or equal to 2% by volume of the occluded macropores of the sorbent material.
18. 18. The method according to claim 17, the method comprising: The adsorbent material is removed from the second salt solution.
19. 19. The method of claim 17, wherein the washing is performed with water and the first metal carbonate is water soluble and the second metal carbonate is water insoluble.
20. 20. The method of claim 19, wherein the first metal acetate is potassium acetate, the first metal carbonate is potassium carbonate, the second metal acetate is barium acetate, and the second metal carbonate is barium carbonate.

Description

Adsorbent material, adsorption system and adsorption process Cross Reference to Related Applications The present application claims priority from U.S. non-provisional application Ser. No. 18/501,069 filed on 3/11/2023, which is incorporated herein by reference. Technical Field The present innovation relates to adsorbent materials, adsorption systems, adsorption processes, adsorbers, and methods of making and using the same for purifying a hydrogen product stream. Background Adsorbers typically come in four different common configurations, vertical cross-flow, horizontal, and radial. Exemplary adsorbers, adsorption systems, and adsorbent materials that may be used for adsorbers may be described in U.S. Pat. nos. 3,176,444, 3,430,418, 3,564,816, 3,986,849, no. 4,541,851, no. first, second, third, fourth, fifth, sixth, seventh, eighth, and eighth first, second, third, fourth, fifth, sixth, seventh, eighth, and eighth U.S. patent application publication nos. 2011/0206581, 2011/0219950, 2019/0291078 and 2023/0027070, canadian patent publication No. 2,357,276A, chinese patent publication No. CN a and european patent publication No. EP 1 417 995 A1. Temperature Swing Adsorption (TSA), pressure swing adsorption (VSA), pressure Swing Adsorption (PSA), and pressure swing vacuum adsorption (PVSA) are adsorbent systems that can be used in different types of purification systems. For example, PSA systems are used to recover and purify gaseous products, such as hydrogen. Disclosure of Invention In PSA-related systems (e.g., PSA systems or PVSA systems), the feed gas stream is typically delivered to an adsorbent bed comprising a plurality of such beds at an elevated pressure that is a pressure above atmospheric pressure (e.g., 1 atm). Hydrogen purification PSA systems can be used in steam reformer applications, for example, where carbon dioxide (CO 2), carbon monoxide (CO), methane (CH 4), and nitrogen (N2) impurities can be selectively adsorbed to produce a high purity hydrogen (H2) stream at relatively high pressures. We have determined that variations in adsorbent bed temperature that occur during PSA or PVSA processing can have a significant impact on the adsorption performance for removing impurities. Adsorption is an exothermic process such that during the high pressure feed step the bed heats up, which effectively reduces the adsorption capacity of the bed. Alternatively, desorption is an endothermic process, such that during the desorption step (depressurization, purge, evacuation, etc.), the bed cools down, which reduces the amount of desorbed gas, as the temperature of the bed has been reduced. Fluctuations in bed temperature can significantly affect the effective bed capacity in at least two ways, (1) it can reduce the adsorbate loading during the adsorption step, and (2) it can increase the adsorbate loading during the desorption step, both of which serve to reduce the operating capacity of the adsorbent material bed. We also determined that the adiabatic nature of the process may result in a significant increase in bed size compared to the same process operating in isothermal mode. At a given point of the bed of adsorbent material in the industrial adsorber, the temperature difference between the highest temperature during adsorption and the lowest temperature during desorption may be substantial (e.g., 65 ℃ or greater than 65 ℃). We have determined that it would be beneficial to reduce temperature fluctuations of the adsorbent material bed. This is especially true for PSA systems and PVSA systems. Reducing the temperature difference between the highest temperature during adsorption and the lowest temperature during desorption may effectively increase the working capacity of the adsorbent material bed to allow the adsorbent material to work more effectively for purification. Such improvements may result in reduced adsorber size because less adsorbent material is required for purification (e.g., bed productivity is increased by increasing the flow rate of product available per unit volume of adsorbent material bed), and/or may allow for higher operating efficiencies (product recovery) by reducing product losses during venting, purging, and/or evacuation of the adsorber vessel during the regeneration step or desorption step. We have also determined that an adsorbent material for improving the performance of an adsorbent material used in PSA-related systems (e.g., PSA systems, PVSA systems, etc.) would preferably avoid requiring the use of a unique vessel internal structure (or at least limiting its use) for attempting to limit the temperature difference between the temperature of the adsorbent material bed during adsorption and the temperature of the adsorbent material bed during regeneration or desorption. The use of such internal structures can increase the structural complexity of the adsorber vessel design, which can increase their capital costs. In some cases, such internal structures can also make layerin