Recycled hydrogen purification adsorbent and regeneration method and performance evaluation method thereof

Abstract

The invention discloses a recycled hydrogen purification adsorbent as well as a regeneration method and a performance evaluation method thereof. The regeneration method comprises the following steps: S101, pretreating an inactivated and off-line recycled hydrogen purification adsorbent in a micro-oxygen atmosphere; s102, performing high-temperature treatment on the pretreated adsorbent in a pure inert atmosphere; and S103, carrying out activating treatment on the adsorbent subjected to high-temperature treatment in a chlorine-containing atmosphere. According to the method, the activity of the inactivated adsorbent can be well recovered, good performance can be kept in the continuous adsorption operation process, and cyclic utilization of the adsorbent after regeneration is achieved.

Description

Technical Field

[0001] This invention belongs to the field of polycrystalline silicon technology, specifically relating to a method for recovering hydrogen purification adsorbent and its regeneration, as well as a method for evaluating its performance. Background Technology

[0002] In the polysilicon production process, the efficient recovery and recycling of reduction tail gas is a core element for achieving closed-loop material management and reducing production costs. Reduction tail gas is rich in chlorosilanes (such as SiHCl3 and SiCl4) and hydrogen (H2). Hydrogen is a key raw material in the reduction process, and a 1% increase in hydrogen recovery and utilization rate can reduce polysilicon production costs by approximately 0.5% to 1%. However, during the recovery process, hydrogen inevitably carries trace amounts of light component impurities, especially boron (B) and phosphorus (P) hydrides (such as B2H6 and PH3). Even at levels as low as ppb, these impurities can severely affect the electrical performance of polysilicon products, leading to decreased conversion efficiency in photovoltaic-grade polysilicon or failure of electronic-grade polysilicon to meet device requirements.

[0003] Currently, industrial hydrogen purification mainly employs pressure swing adsorption (PSA) technology, with over 90% of polysilicon manufacturers choosing conventional activated carbon as the adsorbent. Activated carbon, with its abundant pore structure and low cost, can effectively remove impurities such as CO2 and CH4 from hydrogen. However, limited by the equilibrium characteristics of physical adsorption, it has a low adsorption capacity for light boron and phosphorus impurities with weak polarity and low boiling points (such as B2H6 boiling point -92.5℃ and PH3 boiling point -87.7℃), and is easily affected by temperature fluctuations, leading to impurity penetration. This makes it difficult to meet the stringent requirements for boron and phosphorus content in hydrogen during polysilicon production.

[0004] To overcome these limitations, researchers have developed modified adsorbents based on porous supports loaded with oxidizing active metals. These adsorbents enhance the removal efficiency of boron and phosphorus impurities through the synergistic effect of chemisorption and catalytic oxidation. For example, loading active metal oxides (such as CuO) onto activated carbon or alumina supports allows for the conversion of PH3 into stable phosphates or phosphides through a redox reaction between the CuO active sites and PH3. The adsorption capacity of this modified adsorbent can reach 8-10 times that of conventional activated carbon. However, the reaction directly leads to the loss of activity of the modified adsorbent. Currently, most technologies focus on adsorbent modification and the development of novel adsorbents, with insufficient research on the regeneration of deactivated adsorbents, and regeneration and reuse have not yet been achieved. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to address the above-mentioned shortcomings of the existing technology by providing a method for recovering hydrogen purification adsorbent and its regeneration and performance evaluation. This regeneration method can effectively restore the activity of the deactivated adsorbent, maintain good performance during continuous adsorption operation, and realize the recycling of the adsorbent after regeneration.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is:

[0007] According to a first aspect of the present invention, a method for recovering a hydrogen purification adsorbent and regenerating the same is provided, comprising:

[0008] S101, the deactivated hydrogen purification adsorbent is pretreated in a micro-oxygen atmosphere;

[0009] S102, the pretreated adsorbent is subjected to high-temperature treatment under a pure inert atmosphere;

[0010] S103 involves activating the adsorbent after high-temperature treatment in a chlorine-containing atmosphere.

[0011] Optionally, the micro-oxygen atmosphere is a mixture of inert gas and oxygen or air, wherein the volume fraction of oxygen is 0.5% to 5%.

[0012] Optionally, the volume hourly space velocity (VHSV) of the micro-oxygen atmosphere is 30 h⁻¹. -1 ~70h -1 .

[0013] Optionally, the pretreatment temperature is 150℃~250℃, and the heating rate is 5℃ / min~10℃ / min.

[0014] Optionally, the pure inert atmosphere is nitrogen or argon with a purity of ≥99.9%, wherein the impurity content is ≤0.1%.

[0015] Optionally, the volume hourly space velocity of the purely inert atmosphere is 80 h⁻¹. -1 ~180h -1 .

[0016] Optionally, the high-temperature treatment temperature is 300℃~500℃, and the heating rate is 5℃ / min~10℃ / min.

[0017] Optionally, the chlorine-containing atmosphere is a mixture of hydrogen chloride, an auxiliary chlorine-containing component, and a balance gas. The volume fraction of the hydrogen chloride is 5% to 20%, the auxiliary chlorine-containing component is at least one of thionyl chloride, thionyl chloride, hypochlorous acid, chlorine, chloromethane, and N-chlorosuccinimide, and the volume fraction of the auxiliary chlorine-containing component is 1% to 10%. The balance gas is an inert gas or hydrogen with a purity ≥ 99.9%.

[0018] Optionally, the volume hourly space velocity (VHSV) of the chlorine-containing atmosphere is 80 h⁻¹. -1 ~150h -1 .

[0019] Optionally, the activation treatment temperature is 350℃~450℃.

[0020] According to a second aspect of the present invention, a hydrogen purification adsorbent for recovery is also provided, which is obtained by regenerating the hydrogen purification adsorbent for recovery using the regeneration method described above.

[0021] According to a third aspect of the present invention, a method for evaluating the performance of a recovered hydrogen purification adsorbent regenerated by the above-described regeneration method is also provided, comprising:

[0022] S201, accurately weigh the regenerated hydrogen purification adsorbent, fill it into the adsorption column, and perform an airtightness check.

[0023] S202. After the airtightness check is completed, a phosphine mixture is introduced for adsorption experiment. The PH3 concentration at the tail gas end of the adsorption column is detected at regular intervals. The PH3 concentration is 0.1~1000ppm, the volume hourly space velocity of the PH3 mixture is 30~600ml / min·ml, and the temperature of the adsorption experiment is controlled at 0~80℃.

[0024] The beneficial effects of this invention are:

[0025] (1) High regeneration efficiency: Through a three-step synergistic process, the adsorption effect of the deactivated hydrogen purification adsorbent on PH3 can be restored to more than 80% of the initial value.

[0026] (2) Low loss of active components: Step S103 can avoid the dissolution and loss of copper-based components, with a Cu loss rate of ≤5%, thus extending the service life of the adsorbent.

[0027] (3) Strong process compatibility: The regeneration process can be coupled with the hydrogen purification system of the polysilicon plant (such as the pressure swing adsorption PSA device), utilizing the existing raw materials such as nitrogen and HCl in the plant, without the need for additional equipment, thus reducing the cost of industrial application; in addition, the three-step process can be carried out continuously in the same fixed-bed reactor without the need to transfer the adsorbent, reducing the number of operation steps, and is suitable for continuous production of polysilicon. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the regeneration method for recovering hydrogen purification adsorbent in an embodiment of the present invention;

[0029] Figure 2 This is a diagram illustrating the effect of the regeneration method for recovering hydrogen purification adsorbent in an embodiment of the present invention. Detailed Implementation

[0030] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0031] It is understood that the specific embodiments and accompanying drawings described herein are merely for explaining the invention and are not intended to limit the invention.

[0032] It is understood that, without conflict, the various embodiments and features in the embodiments of the present invention can be combined with each other.

[0033] It is understood that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, while the parts unrelated to the present invention are not shown in the drawings.

[0034] To address the problem in existing technologies where adsorbents using metals, particularly copper metal salts or oxides, as active components rapidly lose their activity during hydrogen recovery and purification due to chemical reactions with reducing impurities such as PH3, resulting in the formation of elemental copper or phosphides, this invention provides a regeneration method for hydrogen recovery and purification adsorbents, comprising:

[0035] S101, Micro-oxygen Pretreatment: The deactivated hydrogen purification adsorbent (hereinafter referred to as the adsorbent) is introduced into the fixed-bed regenerator under a micro-oxygen atmosphere. Pretreatment is performed in this atmosphere to oxidize the strongly bound copper-phosphorus compounds on the adsorbent surface into easily removable phosphoric acid compounds. The adsorbent comprises a metallic active component and a support. The active component is a copper salt and its oxides, or a mixture of copper with one or more metal salts / oxides from iron, cobalt, nickel, zinc, cerium, calcium, magnesium, sodium, etc. The support is one of the following materials with abundant pores and a high specific surface area: activated carbon, alumina, molecular sieve, silica gel, etc., preferably activated carbon. Deactivation refers to the adsorbent's removal rate of PH3 decreasing to below 30% of its initial value.

[0036] S102, High-temperature treatment under inert atmosphere: After the pretreatment is completed, the micro-oxygen atmosphere is stopped and the pure inert atmosphere is switched to be introduced. The pretreated adsorbent is then subjected to high-temperature treatment under a pure inert atmosphere to convert the inactive Cu element in the adsorbent into copper oxide compounds with adsorption activity.

[0037] S103, Chlorine-containing activation treatment: After the high-temperature treatment is completed, the pure inert atmosphere is stopped and replaced with a chlorine-containing atmosphere. The adsorbent after high-temperature treatment is activated in the chlorine-containing atmosphere to convert copper oxide / phosphate metal salt into highly active copper chloride compound, thereby regenerating the activity of the deactivated adsorbent and restoring its initial phosphorus removal capacity.

[0038] Furthermore, the present invention also provides a regenerated hydrogen purification adsorbent using the above-described regeneration method for the recovered hydrogen purification adsorbent.

[0039] Furthermore, to verify the performance of the regenerated adsorbent described above, this invention also provides a method for evaluating the performance of the regenerated hydrogen purification adsorbent described above, comprising:

[0040] S201. Accurately weigh a certain amount of the regenerated hydrogen purification adsorbent described above, fill it into the adsorption column, and perform an airtightness check.

[0041] S202. After the airtightness check is completed, a phosphine mixture is introduced for adsorption experiment. The concentration of phosphine (i.e., PH3) at the tail end of the adsorption column is detected at regular intervals. The concentration of PH3 is 0.1~1000ppm (mole fraction), the volume hourly space velocity of the PH3 mixture is 30~600ml (gas) / min·ml (adsorbent), and the temperature of the adsorption experiment is controlled at 0~80℃.

[0042] This invention utilizes a three-step synergistic process of "micro-oxygen pretreatment - inert atmosphere high-temperature treatment - chlorine-containing activation treatment" to effectively restore the activity of the deactivated hydrogen purification adsorbent from the production line. This process maintains good performance during continuous adsorption operation, enabling the adsorbent to be recycled after regeneration and can be used in continuous polycrystalline silicon production.

[0043] Example 1

[0044] This embodiment discloses a method for regenerating a hydrogen purification adsorbent, including:

[0045] S101, Micro-oxygen pretreatment: The deactivated hydrogen purification adsorbent is pretreated in a micro-oxygen atmosphere, wherein the micro-oxygen atmosphere is a mixture of an inert gas (e.g., nitrogen or argon with a purity ≥ 99.9%) and oxygen or air, the volume fraction of oxygen is 0.5%~5%, more preferably 1%~3%, and the inert gas is a balance gas.

[0046] In some embodiments, the volume hourly space velocity (VHSV) of the micro-oxygen atmosphere is 30 h⁻¹. -1 ~70h -1 This ensures that the micro-oxygen atmosphere is in full contact with the adsorbent, guaranteeing the pretreatment effect.

[0047] In some embodiments, the pretreatment temperature is 150°C to 250°C, more preferably 180°C to 220°C, and the heating rate is 5°C / min to 10°C / min to avoid local overheating that could lead to sintering of the adsorbent carrier.

[0048] In some embodiments, the pretreatment time is 2h to 12h, more preferably 5h to 8h, depending on the phosphorus content of the adsorbent.

[0049] S102, High-temperature treatment in an inert atmosphere: The pretreated adsorbent is subjected to high-temperature treatment in a pure inert atmosphere, wherein the pure inert atmosphere is nitrogen or argon with a purity of ≥99.9%, and the impurity (O2, H2O) content in the pure inert atmosphere is ≤0.1% to avoid secondary reaction with the adsorbent.

[0050] In some embodiments, the volume hourly space velocity of the purely inert atmosphere is 80 h⁻¹. -1 ~180h -1 Preferably 100h -1 ~160h -1 This accelerates the desorption and removal of phosphate compounds.

[0051] In some embodiments, the high-temperature treatment temperature is 300℃~500℃, more preferably 350℃~450℃, and the heating rate is 5℃ / min~10℃ / min. The temperature can be directly increased from the pretreatment temperature (150℃~250℃) to the high-temperature treatment without cooling, making the operation simple and convenient. By adopting the above-mentioned high-temperature treatment method, insufficient treatment of active species on the adsorbent surface due to excessively low temperatures can be avoided, while the aggregation of active species due to excessively high temperatures can be avoided, thus preventing negative impacts on post-regeneration performance.

[0052] In some embodiments, the high-temperature treatment time is 3h to 8h, more preferably 4h to 6h, to avoid insufficient treatment of active species on the adsorbent surface due to too short a time, and to avoid the aggregation of active species due to too long a time, which would affect the performance after regeneration.

[0053] S103, Chlorine-containing activation treatment: The adsorbent after high-temperature treatment is activated in a chlorine-containing atmosphere, wherein the chlorine-containing atmosphere is a mixture of hydrogen chloride, auxiliary chlorine-containing components, and a balance gas. The volume fraction of hydrogen chloride is 5%~20%, more preferably 10%~15%. The auxiliary chlorine-containing components are at least one of thionyl chloride (SOCl2), thionyl chloride (SO2Cl2), hypochlorous acid (HClO, which is introduced by atomization of aqueous solution), chlorine (Cl2), chloromethane (CH3Cl), and N-chlorosuccinimide (introduced by inert gas carrier). The volume fraction of the auxiliary chlorine-containing components is 1%~10%, more preferably 3%~8%. The balance gas is an inert gas or hydrogen with a purity ≥99.9%.

[0054] In some embodiments, the volume hourly space velocity (VHSV) of the chlorine-containing atmosphere is 80 h⁻¹. -1 ~150h -1 More preferably 100h -1 ~120h -1 This ensures that the chlorine-containing components are in full contact with the copper species, avoiding localized over-contamination that could lead to carrier corrosion.

[0055] In some embodiments, the activation temperature is matched with the high-temperature treatment temperature in step S102, for example, it can be 350°C to 450°C, to ensure that the copper oxide compound and the chlorine-containing component react fully.

[0056] In some embodiments, the activation treatment time is 2h to 5h, more preferably 3h to 4h, to avoid insufficient treatment of active species on the adsorbent surface due to too short a time, and to avoid the aggregation of active species due to too long a time, which would affect the performance after regeneration.

[0057] This embodiment also discloses a hydrogen purification adsorbent that has been regenerated using the method described above.

[0058] This embodiment also discloses a method for evaluating the performance of the regenerated hydrogen purification adsorbent described above, the steps of which include:

[0059] S201. A certain amount of the regenerated adsorbent described above is accurately weighed using an electronic balance, filled into the adsorption column, and the airtightness is checked using nitrogen as the purging gas.

[0060] S202. After the airtightness check is completed, a phosphine mixture is introduced for adsorption experiments. The concentration of phosphine (i.e., PH3) at the tail end of the adsorption column is detected at regular intervals (e.g., half an hour). The PH3 mixture is a PH3 / H2 mixture with a PH3 concentration of 0.1~1000ppm (mole fraction) and a PH3 mixture volume hourly space velocity of 30~600ml (gas) / min·ml (adsorbent). The temperature of the adsorption experiment is controlled at 0~80℃.

[0061] Testing showed that the regenerated adsorbent in this embodiment could restore its adsorption effect on PH3 to more than 80% of its initial value.

[0062] The regeneration method for the hydrogen purification adsorbent in this embodiment can achieve the following effects:

[0063] (1) High regeneration efficiency: Through a three-step synergistic process, the adsorption effect of the deactivated hydrogen purification adsorbent on PH3 can be restored to more than 80% of the initial value.

[0064] (2) Low loss of active components: Step S103 can avoid the dissolution and loss of copper-based components, with a Cu loss rate of ≤5%, thus extending the service life of the adsorbent.

[0065] (3) Strong process compatibility: The regeneration process can be coupled with the hydrogen purification system of the polysilicon plant (such as the pressure swing adsorption PSA device), utilizing the existing raw materials such as nitrogen and HCl in the plant, without the need for additional equipment, thus reducing the cost of industrial application; in addition, the three-step process can be carried out continuously in the same fixed-bed reactor without the need to transfer the adsorbent, reducing the number of operation steps, and is suitable for continuous production of polysilicon.

[0066] Example 2

[0067] This embodiment discloses a regeneration method for recovering hydrogen purification adsorbents. The adsorbent is a Cu / activated carbon modified adsorbent (initial Cu loading 10wt%, loading 5g). After adsorption with phosphine standard gas (containing 100ppm pH3) for 300 hours, it is taken offline. At this point, its pH3 adsorption removal rate drops to 25.7% (26.3% of the initial value, which was 98%). The deactivated adsorbent is denoted as MD. Specific steps include:

[0068] S101, Micro-oxygen Pretreatment: The deactivated hydrogen purification adsorbent is loaded into a fixed-bed regeneration reactor and pretreated by introducing a micro-oxygen atmosphere. The volume fraction of oxygen in the micro-oxygen atmosphere is 1%, nitrogen is used as the balance gas, the heating rate is 5℃ / min, the target temperature is 180℃, and the volume hourly space velocity of the micro-oxygen atmosphere is 60 h⁻¹. -1 The pretreatment time is 8 hours;

[0069] S102, High-Temperature Treatment in an Inert Atmosphere: After pretreatment, the micro-oxygen atmosphere is stopped, and the process is switched to pure inert atmosphere (nitrogen purity > 99.9%). The temperature is increased directly from the pretreatment temperature of 180℃ at a rate of 5℃ / min, with a target temperature of 450℃. The volume hourly space velocity (VHSV) of the pure inert atmosphere is 160 h⁻¹. -1 The pretreated adsorbent was subjected to high-temperature treatment under a pure inert atmosphere for 4 hours.

[0070] S103, Chlorine-containing activation treatment: After the high-temperature treatment, the atmosphere is switched to a chlorine-containing atmosphere (HCl 10% + SOCl2 3%), and the equilibrium gas is nitrogen with a purity >99.9%. The volume hourly space velocity (VHSV) of the chlorine-containing atmosphere is 100 h⁻¹. -1 The adsorbent after high-temperature treatment is activated in a chlorine-containing atmosphere. The activation temperature is maintained at 450℃ and the activation time is 3 hours. After the activation treatment is completed, the regenerated adsorbent is obtained, denoted as M-R1.

[0071] Example 3

[0072] This embodiment discloses a regeneration method for recovering hydrogen purification adsorbent, which is basically the same as that in embodiment 2, except that: the volume fraction of oxygen in the micro-oxygen atmosphere is 1% is changed to 3% in step S101, and the pretreatment time is changed from 8h to 5h; the regenerated adsorbent is denoted as M-R2.

[0073] Example 4

[0074] This embodiment discloses a regeneration method for recovering hydrogen purification adsorbents, which is basically the same as that in Embodiment 2, except that the "target temperature 180℃" in step S101 is modified to "target temperature 220℃" and the "volume hourly space velocity of the micro-oxygen atmosphere is 60 h⁻¹". -1 "Modified to "The volume hourly space velocity of the micro-oxygen atmosphere is 40 h⁻¹" -1 The regenerated adsorbent is designated as M-R3.

[0075] Example 5

[0076] This embodiment discloses a regeneration method for recovering hydrogen purification adsorbent, which is basically the same as that in Embodiment 2, except that: the "target temperature is 450℃" in step S102 is changed to "target temperature is 350℃", and the "high temperature treatment time is 4h" is changed to "high temperature treatment time is 8h"; the regenerated adsorbent is denoted as M-R4.

[0077] Example 6

[0078] This embodiment discloses a regeneration method for recovering hydrogen purification adsorbents. The scheme is basically the same as in Embodiment 2, except that in step S102, "purity > 99.9% nitrogen" is changed to "purity > 99.9% argon," and the volume hourly space velocity (VHSV) of the pure inert atmosphere is 160 h⁻¹. -1 "Modified to "The volume hourly space velocity of a purely inert atmosphere is 100 h⁻¹" -1 The phrase "the high-temperature treatment time is 4 hours" is revised to "the high-temperature treatment time is 6 hours"; the regenerated adsorbent is designated as M-R5.

[0079] Example 7

[0080] This embodiment discloses a regeneration method for recovering hydrogen purification adsorbent, which is basically the same as that in Embodiment 2, except that "HCl 10% + SOCl2 3%" in step S103 is modified to "HCl 10% + Cl2 3%"; the regenerated adsorbent is denoted as M-R6.

[0081] Example 8

[0082] This embodiment discloses a regeneration method for recovering hydrogen purification adsorbent, which is basically the same as that in Embodiment 2, except that: in step S103, "the activation treatment temperature is maintained at 450°C" is changed to "the activation treatment temperature is maintained at 350°C", and "HCl 10% + SOCl2 3%" is changed to "HCl 10% + HClO 8%"; the regenerated adsorbent is denoted as M-R7.

[0083] Example 9

[0084] This embodiment discloses a regeneration method for recovering hydrogen purification adsorbents, which is basically the same as that in Embodiment 2, except that the volume hourly space velocity of the chlorine-containing atmosphere is set to 100 h⁻¹ in step S103. -1 "Modified to "The volume hourly space velocity of the chlorine-containing atmosphere is 120 h⁻¹" -1 The regenerated adsorbent is designated as M-R8.

[0085] Example 10

[0086] This embodiment discloses a regeneration method for recovering hydrogen purification adsorbents, which differs from that of Embodiment 2 in that:

[0087] S101, Micro-oxygen Pretreatment: The deactivated hydrogen purification adsorbent is loaded into a fixed-bed regeneration reactor and pretreated by introducing a micro-oxygen atmosphere. The volume fraction of oxygen in the micro-oxygen atmosphere is 0.5%, nitrogen is used as the balance gas, the heating rate is 8℃ / min, the target temperature is 150℃, and the volume hourly space velocity (VHSV) of the micro-oxygen atmosphere is 30 h⁻¹. -1 The pretreatment time is 2 hours;

[0088] S102, High-Temperature Treatment in an Inert Atmosphere: After pretreatment, the micro-oxygen atmosphere is stopped, and the process is switched to pure inert atmosphere (argon purity > 99.9%). The temperature is increased directly from the pretreatment temperature of 150℃ at a rate of 8℃ / min, with a target temperature of 300℃. The volume hourly space velocity (VHSV) of the pure inert atmosphere is 80 h⁻¹. -1 The pretreated adsorbent was subjected to high-temperature treatment under a pure inert atmosphere for 3 hours.

[0089] S103, Chlorine-containing activation treatment: After the high-temperature treatment, the atmosphere is switched to a chlorine-containing atmosphere (HCl 5% + Cl2 5% + CH3Cl 5%), and the equilibrium gas is nitrogen with a purity >99.9%. The volume hourly space velocity (VHSV) of the chlorine-containing atmosphere is 80 h⁻¹. -1 The adsorbent after high-temperature treatment is activated in a chlorine-containing atmosphere. The activation temperature is maintained at 400℃ and the activation time is 2 hours. After the activation treatment is completed, the regenerated adsorbent is obtained, which is denoted as M-R9.

[0090] Example 11

[0091] This embodiment discloses a regeneration method for recovering hydrogen purification adsorbents, which differs from that of Embodiment 2 in that:

[0092] S101, Micro-oxygen Pretreatment: The deactivated hydrogen purification adsorbent is loaded into a fixed-bed regeneration reactor and pretreated by introducing a micro-oxygen atmosphere. The micro-oxygen atmosphere contains 5% oxygen by volume, nitrogen as the balance gas, a heating rate of 10℃ / min, a target temperature of 250℃, and a volume hourly space velocity (VHSV) of 70 h⁻¹. -1 The pretreatment time is 12 hours;

[0093] S102, High-Temperature Treatment in an Inert Atmosphere: After pretreatment, the micro-oxygen atmosphere is stopped, and the process is switched to pure inert atmosphere (argon purity > 99.9%). The temperature is increased directly from the pretreatment temperature of 250℃ at a rate of 10℃ / min, with a target temperature of 500℃. The volume hourly space velocity (VHSV) of the pure inert atmosphere is 180 h⁻¹. -1 The pretreated adsorbent was subjected to high-temperature treatment under a pure inert atmosphere for 5 hours.

[0094] S103, Chlorine-containing activation treatment: After the high-temperature treatment, the atmosphere is switched to a chlorine-containing atmosphere (HCl 20% + SOCl2 1%), the equilibrium gas is nitrogen with a purity >99.9%, and the volume hourly space velocity of the chlorine-containing atmosphere is 150 h⁻¹. -1 The adsorbent after high-temperature treatment is activated in a chlorine-containing atmosphere. The activation temperature is maintained at 380℃ and the activation time is 5 hours. After the activation treatment is completed, the regenerated adsorbent is obtained, denoted as M-R10.

[0095] Comparative Example 1

[0096] This comparative example discloses a regeneration method for recovering hydrogen purification adsorbent, which is basically the same as that in Example 2, except that the "volume fraction of oxygen in the micro-oxygen atmosphere is 1%" in step S101 is changed to "volume fraction of oxygen in the micro-oxygen atmosphere is 0.1%"; the regenerated adsorbent is denoted as RM-R1.

[0097] Comparative Example 2

[0098] This comparative example discloses a regeneration method for recovering hydrogen purification adsorbent, which is basically the same as that in Example 2, except that "purity > 99.9% nitrogen" in step S101 is changed to "air"; the regenerated adsorbent is denoted as RM-R2.

[0099] Comparative Example 3

[0100] This comparative example discloses a regeneration method for recovering hydrogen purification adsorbents, which is basically the same as that in Example 2, except that step S102 is removed and step S103 is modified to: "After the pretreatment is completed, switch to a chlorine-containing atmosphere (wherein, HCl 10% + SOCl2 3%) is introduced, the equilibrium gas is nitrogen with a purity >99.9%, and the temperature is directly increased from the pretreatment temperature of 180°C at a heating rate of 5°C / min, with a target temperature of 450°C, and the volume hourly space velocity of the chlorine-containing atmosphere is 100 h⁻¹." -1 The pretreated adsorbent is then activated directly in a chlorine-containing atmosphere for 3 hours; the regenerated adsorbent is designated RM-R3.

[0101] Comparative Example 4

[0102] This comparative example discloses a regeneration method for recovering hydrogen purification adsorbent. The difference between this method and Example 2 is that only the inert atmosphere high-temperature treatment in step S102 is performed, without the "micro-oxygen pretreatment" and "chlorine-containing activation treatment"; the regenerated adsorbent is designated as RM-R4.

[0103] Comparative Example 5

[0104] This comparative example discloses a regeneration method for recovering hydrogen purification adsorbent. The difference between this method and Example 2 is that only the chlorine-containing activation treatment in step S103 is performed, without the "micro-oxygen pretreatment" and "inert atmosphere high-temperature treatment"; the regenerated adsorbent is designated as RM-R5.

[0105] Comparative Example 6

[0106] This comparative example discloses a regeneration method for recovering hydrogen purification adsorbent. The difference between this method and Example 2 is that: in Comparative Example 6, the deactivated hydrogen purification adsorbent is first soaked in a 10wt% HCl solution at 80°C for 6 hours, then washed with deionized water until neutral, and then dried at 120°C. The three-step process in Example 2 (i.e., no "micro-oxygen pretreatment", "inert atmosphere high-temperature treatment" and "chlorine-containing activation treatment") is omitted. The regenerated adsorbent is designated as RM-R6.

[0107] The performance of the fresh adsorbent, the deactivated adsorbent, and the regenerated adsorbents from Examples 2-9 and Comparative Examples 1-4 were tested in the following details:

[0108] The various adsorbents were accurately weighed using an electronic balance and then filled into adsorption columns of the same specifications. Nitrogen was used as the purging gas to check for air tightness.

[0109] After the airtightness check was completed, an adsorption experiment was conducted by introducing a PH3 mixture. The concentration of phosphine at the tail end of the adsorption column was measured after 2 hours of experimentation using spectrophotometry. The PH3 mixture was a PH3 / H2 mixture with a PH3 concentration of 100 ppm (mole fraction), a volume hourly space velocity of 300 ml (gas) / min·ml (adsorbent), and the adsorption experiment temperature was controlled at 30℃.

[0110] Data from the adsorption experiment at 2 hours were compared. Table 1 below shows the removal data of PH3 impurities in the PH3 mixture from fresh adsorbent (denoted as Fresh), deactivated adsorbent, and regenerated adsorbents from Examples 2-11 and Comparative Examples 1-4. Each set of data was tested in parallel three times, and the average value was taken. The formula for calculating the PH3 adsorption rate is:

[0111] Impurity adsorption rate Y = [(Initial impurity content in the mixture before adsorption - Impurity content in the mixture after adsorption) / (Initial impurity content in the mixture before adsorption)] × 100%.

[0112] Table 1 Performance Test Results

[0113]

[0114] As shown in Table 1, the regenerated adsorbents in Examples 2-11 showed a significant improvement in PH3 adsorption rate compared to the adsorbents from the deactivated line. This demonstrates that the present invention, through a three-step process of "micro-oxygen pretreatment - inert atmosphere high-temperature treatment - chlorine-containing activation treatment," can effectively restore the activity of the hydrogen purification adsorbent from the deactivated line. Furthermore, within a specific parameter range, the adsorption capacity recovery rate can reach >90%, which is significantly higher than the PH3 adsorption rate of the regenerated adsorbents in Comparative Examples 1-4. Comparative Examples 1-4 cannot achieve the same effect as the technical solution of the present invention, fully demonstrating the inventiveness and practicality of the present invention.

[0115] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A method for regenerating a hydrogen purification adsorbent, characterized in that, include: S101, the deactivated hydrogen purification adsorbent is pretreated in a micro-oxygen atmosphere; S102, the pretreated adsorbent is subjected to high-temperature treatment under a pure inert atmosphere; S103 involves activating the adsorbent after high-temperature treatment in a chlorine-containing atmosphere.

2. The regeneration method for the hydrogen purification adsorbent according to claim 1, characterized in that, The micro-oxygen atmosphere is a mixture of inert gas and oxygen or air, wherein the volume fraction of oxygen is 0.5% to 5%.

3. The regeneration method for the hydrogen purification adsorbent according to claim 1, characterized in that, The volume hourly space velocity of the micro-oxygen atmosphere is 30 h⁻¹. -1 ~70h -1 .

4. The regeneration method for the hydrogen purification adsorbent according to claim 1, characterized in that, The pretreatment temperature is 150℃~250℃, and the heating rate is 5℃ / min~10℃ / min.

5. The regeneration method for the hydrogen purification adsorbent according to claim 1, characterized in that, The pure inert atmosphere is nitrogen or argon with a purity of ≥99.9%, wherein the impurity content is ≤0.1%.

6. The regeneration method for the hydrogen purification adsorbent according to claim 1, characterized in that, The volume hourly space velocity of the purely inert atmosphere is 80 h⁻¹. -1 ~180h -1 .

7. The regeneration method for the hydrogen purification adsorbent according to claim 1, characterized in that, The high-temperature treatment is performed at a temperature of 300℃ to 500℃, with a heating rate of 5℃ / min to 10℃ / min.

8. The regeneration method for the hydrogen purification adsorbent according to claim 1, characterized in that, The chlorine-containing atmosphere is a mixture of hydrogen chloride, auxiliary chlorine-containing components, and a balance gas. The volume fraction of the hydrogen chloride is 5% to 20%. The auxiliary chlorine-containing component is at least one selected from thionyl chloride, thionyl chloride, hypochlorous acid, chlorine, chloromethane, and N-chlorosuccinimide, and the volume fraction of the auxiliary chlorine-containing component is 1% to 10%. The balancing gas is an inert gas or hydrogen with a purity of ≥99.9%.

9. The regeneration method for the hydrogen purification adsorbent according to claim 1, characterized in that, The volume hourly space velocity of the chlorine-containing atmosphere is 80 h⁻¹. -1 ~150h -1 .

10. The regeneration method for the hydrogen purification adsorbent according to claim 1, characterized in that, The activation treatment temperature is 350℃~450℃.

11. A hydrogen recovery and purification adsorbent, characterized in that, It is obtained by regenerating the hydrogen purification adsorbent according to any one of claims 1 to 10.

12. A method for evaluating the performance of a hydrogen purification adsorbent regenerated by the regeneration method according to any one of claims 1 to 10, characterized in that, include: S201, accurately weigh the regenerated hydrogen purification adsorbent, fill it into the adsorption column, and perform an airtightness check. S202. After the airtightness check is completed, a phosphine mixture is introduced for adsorption experiment. The PH3 concentration at the tail gas end of the adsorption column is detected at regular intervals. The PH3 concentration is 0.1~1000ppm, the volume hourly space velocity of the PH3 mixture is 30~600ml / min·ml, and the temperature of the adsorption experiment is controlled at 0~80℃.

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