CO adsorbent as well as preparation method and application thereof

Abstract

The invention relates to a CO adsorbent and a preparation method and application thereof, the method comprises the following steps: S1, contacting a porous carbon carrier, a first copper source, a second copper source and water to obtain a contacted carrier; s2, performing primary reduction treatment on the contacted carrier in a first inert atmosphere to obtain an adsorbent intermediate; s3, under the pressurization condition, performing secondary reduction treatment on the adsorbent intermediate in a second inert atmosphere; the first copper source comprises CuCl2; the second copper source comprises Cu (CH3COO) 2; in the step S1, in terms of copper element, the molar ratio of the first copper source to the second copper source is (0.9-1.0): (1.0-1.1); the temperature rise rate of the first reduction treatment is 5 DEG C / min or less. The method disclosed by the invention is simple in steps, industrial-grade production can be realized, Cl2 gas is not generated, and the prepared CO adsorbent is relatively high in monovalent copper content and has good adsorption performance.

Description

Technical Field

[0001] This disclosure relates to the field of adsorption materials, and more specifically, to a CO adsorbent, its preparation method, and its application. Background Technology

[0002] my country is the world's largest hydrogen producer, with leading industrial hydrogen production globally. Currently, domestic hydrogen production methods mainly include industrial by-product hydrogen production, fossil fuel hydrogen production, and water electrolysis. Industrial by-product hydrogen contains a complex variety of impurities, with varying impurity content depending on the source of the feed gas. Among these, impurities such as carbon monoxide and hydrogen sulfide have a significant poisoning effect on the precious metal catalysts in fuel cells. The new national standard for hydrogen used in fuel cells, GB / T 37244-2018 "Fuel Hydrogen for Proton Exchange Membrane Fuel Cell Vehicles," which came into effect on July 1, 2019, specifies detailed requirements for hydrogen purity and impurity content, limiting the concentration of carbon monoxide impurities to below 0.2 ppm.

[0003] CN110270303A discloses a highly efficient carbon monoxide adsorbent and its preparation method. The raw materials used in the preparation of this adsorbent are a mixture of copper chloride and basic copper salt and a high specific surface area support. Literature (Ma, JH; Li, L.; Ren, J.; Li, RF Sep. Purif. Technol. 2010, 76 (1), 89−93.) reports a method for preparing carbon monoxide adsorbents by mixing copper salt solution with activated carbon or molecular sieve support by rotary evaporation followed by calcination under different atmospheres. Literature (Xue, C.; Hao, W.; Cheng, W.; Ma, J.; Li, R. Chem. Eng. J. 2019, 375, No. 122049.) reports a method for preparing carbon monoxide adsorbents by mixing copper salt solution with activated carbon support by rotary evaporation followed by vacuum calcination.

[0004] However, the carbon monoxide adsorption capacity of the above-mentioned adsorbent materials is limited, and corrosive acidic gases are generated during the preparation process, which is not conducive to large-scale production. Summary of the Invention

[0005] The purpose of this disclosure is to provide a CO adsorbent, its preparation method, and its application. The method of this disclosure is simple and does not generate Cl2 gas. The prepared CO adsorbent does not contain elemental Cu and has a high content of monovalent copper, thus exhibiting good adsorption performance.

[0006] To achieve the above objectives, the first aspect of this disclosure provides a method for preparing a CO adsorbent, the method comprising the following steps: S1. The porous carbon support, the first copper source, the second copper source and water are brought into contact to obtain the contacted support; S2. The carrier after contact is subjected to a first reduction treatment under a first inert atmosphere to obtain an adsorbent intermediate; S3. Under pressurized conditions, the adsorbent intermediate is subjected to a second reduction treatment in a second inert atmosphere; The first copper source includes CuCl2; The second copper source includes Cu(CH3COO)2; In step S1, the molar ratio of the first copper source to the second copper source, based on copper element, is (0.9-1.0):(1.0-1.1). The heating rate for the first reduction treatment is less than 5°C / min.

[0007] Optionally, the porous carbon support includes one or more of activated carbon, graphene, carbon, and carbon black; The porous carbon support has a BET specific surface area of ​​1000-2000 m². 2 / g, preferably 1600-2000 m 2 / g.

[0008] Optionally, in step S1, the contact conditions include: a temperature of 25-35°C, a stirring time of 5-8 min, and a settling time of 25-35 min.

[0009] Optionally, in step S1, the molar ratio of the first copper source to the second copper source, based on copper element, is (0.95-1.0):(1.0-1.05). Optionally, the weight ratio of the first copper source, the second copper source, and the porous carbon support is (1.7-10.2):(2.0-12.0):10.0, preferably (3.4-5.1):(4.0-6.0):10.0; The volume ratio of water to the porous carbon support is (1.0-1.2):1.

[0010] Optionally, step S1 further includes: drying the solid-liquid mixture obtained from the contact to obtain the carrier after contact; The drying conditions include: a time of 12-24 hours and a temperature of 60-120℃.

[0011] Optionally, in step S2, the conditions for the first reduction treatment include: a temperature of 200-390℃, preferably 250-350℃; a time of 2-6h, preferably 4-6h; and a heating rate of 2-5℃ / min, preferably 4-5℃ / min. The first inert atmosphere includes one or more of helium, argon, and nitrogen; The flow rate of the first inert atmosphere is 40-120 mL / min, preferably 50-80 mL / min.

[0012] Optionally, in step S3, the conditions for the second reduction treatment include: a temperature of 200-390℃, preferably 250-350℃; a time of 1-4h, preferably 2-3h; a pressure of 0.2-0.5MPa, preferably 0.3-0.4MPa; and a heating rate of 2-8℃ / min, preferably 2-3℃ / min. The second inert atmosphere includes one or more of helium, argon, and nitrogen; The flow rate of the second inert atmosphere is 40-120 mL / min, preferably 50-70 mL / min.

[0013] The second aspect of this disclosure provides a CO adsorbent prepared using the method described in the first aspect of this disclosure.

[0014] Optionally, the CO adsorbent does not contain elemental Cu; Optionally, the BET specific surface area of ​​the CO adsorbent is 800-1100 m². 2 / g, pore volume 0.6-0.8cm³ 3 / g; Optionally, the CO adsorbent contains a monovalent copper active component, and the content of the monovalent copper active component is 4-12 mmol / g, preferably 4-6 mmol / g, relative to the total weight of the CO adsorbent.

[0015] A third aspect of this disclosure provides a method for adsorbing CO, the method comprising: contacting a gas to be treated containing CO with the CO adsorbent described in the second aspect of this disclosure.

[0016] Through the above technical solution, this disclosure uses porous carbon material as a carrier, contacts it with two copper sources and water in a specific ratio, and then performs a first reduction treatment and a second reduction treatment under specific conditions to prepare a CO adsorbent. The method of this disclosure has simple preparation steps, can achieve industrial-scale production, and generates no Cl2 gas. The CO adsorbent prepared by this method does not contain elemental Cu, has a high proportion of monovalent copper, and has a large specific surface area and pore volume, resulting in a long CO adsorption breakthrough time and high CO adsorption capacity, showing good prospects for industrial application.

[0017] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 These are XRD patterns of the adsorbent intermediates prepared in Examples 1-6 of this disclosure; Figure 2 These are XRD patterns of the CO adsorbents prepared in Examples 1-6 and Comparative Examples 1-2 of this disclosure; Figure 3 It is the adsorbent intermediate prepared in Examples 1-6 of this disclosure. Cu 2p XPS plot of energy level; Figure 4 These are the CO adsorption breakthrough curves of the CO adsorbents prepared in Examples 1-6 and Comparative Examples 1-2 of this disclosure. Detailed Implementation

[0019] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0020] The first aspect of this disclosure provides a method for preparing a CO adsorbent, the method comprising the following steps: S1. The porous carbon support, the first copper source, the second copper source and water are brought into contact to obtain the contacted support; S2. The carrier after contact is subjected to a first reduction treatment under a first inert atmosphere to obtain an adsorbent intermediate; S3. Under pressurized conditions, the adsorbent intermediate is subjected to a second reduction treatment in a second inert atmosphere; The first copper source includes CuCl2; The second copper source includes Cu(CH3COO)2; In step S1, the molar ratio of the first copper source to the second copper source, based on copper element, is (0.9-1.0):(1.0-1.1). The heating rate for the first reduction treatment is less than 5°C / min.

[0021] The method disclosed herein uses a porous carbon material with a high specific surface area as a carrier, which is contacted with a solution containing two copper sources in a specific ratio. Then, a first reduction treatment is performed sequentially at a specific heating rate, followed by a second reduction treatment under pressure to prepare a CO adsorbent. The method disclosed herein is simple in steps and has a moderate degree of reduction. No Cl2 gas is generated during the entire preparation process. The CO adsorbent does not contain elemental Cu, has a high CuCl content, and has a large specific surface area and pore volume, resulting in a long CO adsorption breakthrough time and a high CO adsorption capacity, showing good prospects for industrial application.

[0022] In this disclosure, the exhaust gas is detected by moistening blue litmus paper. During the preparation process, the litmus paper does not turn red, indicating that no Cl2 gas is generated. The Cl element exists in the adsorbent in the form of CuCl and optionally CuCl2.

[0023] According to one embodiment of this disclosure, the porous carbon support comprises one or more of activated carbon, graphene, carbon, and carbon black; the BET specific surface area of ​​the porous carbon support is 1000-2000 m². 2 / g, preferably 1600-2000 m 2 / g.

[0024] According to one embodiment of this disclosure, in step S1, the contact conditions include: a temperature of 25-35°C, a stirring time of 5-8 minutes, and a settling time of 25-35 minutes. This disclosure does not impose specific limitations on the stirring speed.

[0025] To further improve the dispersion of copper, according to one embodiment of this disclosure, step S1 includes: contacting a porous carbon support with a solution containing a first copper source and a second copper source to obtain a contacted support; the method for preparing a solution containing the first copper source and the second copper source includes: mixing the first copper source and the second copper source with water, preferably under stirring conditions, for a time of 5-8 minutes and a temperature of 20-30°C, and this disclosure does not impose specific limitations on the stirring speed.

[0026] According to one embodiment of this disclosure, in step S1, the molar ratio of the first copper source to the second copper source, based on copper element, is (0.95-1.0):(1.0-1.05). The above range is conducive to the generation of monovalent copper components and reduces the generation of Cl2.

[0027] According to one embodiment of this disclosure, in step S1, the weight ratio of the first copper source, the second copper source, and the porous carbon support is (1.7-10.2):(2.0-12.0):10.0, preferably (3.4-5.1):(4.0-6.0):10.0; the above embodiment is beneficial to the dispersion of monovalent copper components in the adsorbent, thereby improving the carbon monoxide adsorption performance of the adsorbent.

[0028] According to one embodiment of this disclosure, in step S1, the volume ratio of water to the porous carbon support is (1.0-1.2):1. The above preferred embodiment is beneficial to the dispersion of monovalent copper components in the adsorbent and reduces the three wastes generated during the preparation process.

[0029] According to one embodiment of this disclosure, step S1 further includes: drying the solid-liquid mixture obtained from the contact to obtain the carrier after contact; the drying conditions include: time of 12-24 hours and temperature of 60-120°C; the drying can be carried out in an oven, which is beneficial for industrial production.

[0030] To promote the reduction of divalent copper to monovalent copper and avoid the generation of Cl2 gas, thereby further improving the adsorption performance of the adsorbent, according to one embodiment of this disclosure, the conditions for the first reduction treatment include: a temperature of 200-390℃, preferably 250-350℃; a time of 2-6h, preferably 4-6h; and a heating rate of 2-5℃ / min, preferably 4-5℃ / min.

[0031] According to one embodiment of this disclosure, the first inert atmosphere includes one or more of helium, argon, and nitrogen; the flow rate of the first inert atmosphere is 40-120 mL / min, preferably 50-80 mL / min.

[0032] According to one embodiment of this disclosure, the adsorbent intermediate contains CuCl2, Cu(CH3COO)2, and CuCl; specifically, XRD testing of the adsorbent intermediate reveals peaks within the range of 15-20°, 30-35°, 25-30°, and 45-50° at 2θ angles. θ At 16.1°, the characteristic diffraction peak of CuCl2 is observed; 2 θ The characteristic diffraction peaks of Cu(CH3COO)2 are located at 32.8° and 40.1°. θ The characteristic diffraction peaks of CuCl are located at 28.5° and 47.4°.

[0033] According to one embodiment of this disclosure, in the adsorbent intermediate, the content of monovalent copper is 30-70% by weight, preferably 45-55% by weight, relative to the total weight of copper elements. The above parameters are obtained by X-ray photoelectron spectroscopy (XPS) analysis.

[0034] To promote the reduction of divalent copper to monovalent copper, avoid Cl2 gas, and further improve the adsorption performance of the adsorbent, according to one embodiment of this disclosure, in step S3, the conditions for the second reduction treatment include: a temperature of 200-390℃, preferably 250-350℃; a time of 1-4h, preferably 2-3h; a pressure of 0.2-0.5MPa, preferably 0.3-0.4MPa; and a heating rate of 2-8℃ / min, preferably 2-3℃ / min.

[0035] According to one embodiment of this disclosure, the second inert atmosphere includes one or more of helium, argon, and nitrogen; the flow rate of the second inert atmosphere is 40-120 mL / min, preferably 50-70 mL / min.

[0036] The second aspect of this disclosure provides a CO adsorbent prepared using the method described in the first aspect of this disclosure.

[0037] According to one embodiment of this disclosure, the CO adsorbent does not contain elemental Cu. Preferably, the copper element in the CO adsorbent exists in the form of monovalent copper, i.e., CuCl.

[0038] According to one embodiment of this disclosure, the CO adsorbent contains a monovalent copper active component, and the content of the monovalent copper active component is 4-12 mmol / g, preferably 4-6 mmol / g, relative to the total weight of the CO adsorbent.

[0039] According to one embodiment of this disclosure, the BET specific surface area of ​​the CO adsorbent is 800-1100 m². 2 / g, pore volume 0.6-0.8cm³ 2 / g.

[0040] A third aspect of this disclosure provides a method for adsorbing CO, the method comprising: contacting a gas to be treated containing CO with a CO adsorbent.

[0041] According to one embodiment of this disclosure, the contact conditions include a temperature of 25-60°C and a pressure of 1-21 Bar.

[0042] According to one embodiment of this disclosure, the concentration of CO in the gas to be treated is 1-50 ppm.

[0043] According to one embodiment of this disclosure, the gas to be treated containing CO is a mixture of hydrogen and CO; preferably, the concentration of CO in the mixture is 1-50 ppm; the mixture can be a gas used as fuel for a fuel cell.

[0044] According to one embodiment of this disclosure, the method further includes: heating and / or depressurizing the adsorbent adsorbed with CO, wherein the heating and / or depressurization enables the CO adsorbed on the adsorbent to desorb, thereby recovering the carbon monoxide adsorbent and recycling it for the adsorption of carbon monoxide.

[0045] According to one embodiment of this disclosure, the heating conditions include: a temperature of 60-100°C and a time of 1-3 hours.

[0046] According to one embodiment of this disclosure, the decompression conditions include: a pressure of 50-100 kPa and a time of 1-3 hours.

[0047] The present invention will be described in detail below through embodiments, but is not limited to the following embodiments.

[0048] In the following examples and comparative examples: Unless otherwise specified, all reagents used in this invention are of analytical grade and are commercially available.

[0049] The activated carbon was purchased from Nanping Yuanli Activated Carbon Co., Ltd. (supplier), model / brand YL-600, with a BET specific surface area of ​​1800 m². 2 / g.

[0050] The X-ray photoelectron spectroscopy (XPS) analyzer used was an ESCALab250 X-ray photoelectron spectrometer manufactured by Thermo Fisher Scientific.

[0051] The XRD diffractometer used was a PANalytical X'Pert PRO, with a Cu target, Kα rays, tube voltage (40kV), and a scanning range of 5-50°.

[0052] The specific surface area and pore volume of porous carbon materials and adsorbents were determined using the BET test method. Specifically, a Quantachrome AS-6B analyzer was used for measurement, and the specific surface area was obtained using the Brunauer-Emmett-Taller (BET) method.

[0053] The method for testing the content of monovalent copper active component in adsorbents is to calculate it based on the peak intensity of copper in different valence states in the XRD spectrum.

[0054] Example 1 (1) At 25°C, 2.55 g of copper chloride dihydrate was dissolved in 7 mL of deionized water, and 3.0 g of copper acetate monohydrate was added and stirred for 8 min to dissolve, thus obtaining a solution containing the first copper source and the second copper source. The molar ratio of copper chloride dihydrate to copper acetate monohydrate, calculated by Cu element, is 1:1. (2) Add 5 g of activated carbon to the solution in step (1) and let it soak in the solution. Stir at 25°C for 6 min and let it stand for 25 min to obtain the impregnated carrier. The volume ratio of water to porous carbon support is 1.1:1; The weight ratio of copper chloride dihydrate, copper acetate monohydrate, and activated carbon is 5.1:6.0:10.0; (3) The impregnated carrier is placed in a 60℃ oven for 18 hours to dry, and the dried material is obtained; (4) The dried material was placed in a tube furnace under nitrogen protection for the first reduction treatment. The nitrogen flow rate was 65 mL / min, the heating rate was 4℃ / min, the temperature was 300℃, and the time was 6 h to obtain the adsorbent intermediate. During the process, the moist blue litmus paper placed in the tail gas bottle of the tube furnace did not change color. (5) The adsorbent intermediate was loaded into a carbon monoxide adsorption evaluation device, and the temperature was increased at a rate of 4℃ / min. It was subjected to a secondary reduction treatment for 2h in a nitrogen atmosphere at 300℃, 0.3MPa, and a flow rate of 65mL / min to obtain CO adsorbent A1. The relevant parameters are listed in Table 1. The exhaust gas of the device was collected and tested with moistened blue litmus paper. No discoloration was observed.

[0055] Example 2 (1) At 25°C, 2.55 g of copper chloride dihydrate was dissolved in 8 mL of deionized water, and 3.0 g of copper acetate monohydrate was added and stirred for 7 min to dissolve, thus obtaining a solution containing the first copper source and the second copper source. The molar ratio of copper chloride dihydrate to copper acetate monohydrate, calculated by Cu element, is 1:1. (2) Add 5 g of activated carbon to the solution in step (1) and let it soak in the solution. Stir at 25°C for 5 min and let it stand for 35 min to obtain the impregnated carrier. The volume ratio of water to porous carbon support is 1.2:1; The weight ratio of copper chloride dihydrate, copper acetate monohydrate, and activated carbon is 5.1:6.0:10.0; (3) The impregnated carrier is placed in a 60℃ oven for 12 hours to dry, and the dried material is obtained; (4) The dried material was placed in a tube furnace under nitrogen protection for the first reduction treatment. The nitrogen flow rate was 75 mL / min, the heating rate was 4℃ / min, the calcination temperature was 280℃, and the calcination time was 6 h to obtain the adsorbent intermediate. During the process, the moist blue litmus paper placed in the tail gas bottle of the tube furnace did not change color. (5) The adsorbent intermediate was loaded into a carbon monoxide adsorption evaluation device, and the temperature was increased at a rate of 4℃ / min. It was subjected to a secondary reduction treatment for 2.5h in a nitrogen atmosphere at 300℃, 0.35MPa, and a flow rate of 70mL / min to obtain CO adsorbent A2. The relevant parameters are listed in Table 1. The exhaust gas of the device was collected and tested with moistened blue litmus paper. No color change was observed.

[0056] Example 3 (1) At 26℃, 2.05g of copper chloride dihydrate was dissolved in 7 mL of deionized water, and 2.5g of copper acetate monohydrate was added and stirred for 7 min to dissolve, so as to obtain a solution containing the first copper source and the second copper source. The molar ratio of copper chloride dihydrate to copper acetate monohydrate, calculated by Cu element, is 0.96:1. (2) Add 5 g of activated carbon to the solution in step (1) and let it soak in the solution. Stir at 26°C for 6 min and let it stand for 30 min to obtain the impregnated carrier. The volume ratio of water to porous carbon support is 1.1:1; The weight ratio of copper chloride dihydrate, copper acetate monohydrate, and activated carbon is 4.1:5.0:10.0; (3) The impregnated carrier was placed in a 60℃ oven for drying for 16 hours to obtain dried material; (4) The dried material was placed in a tube furnace under nitrogen protection for the first reduction treatment. The nitrogen flow rate was 60 mL / min, the heating rate was 4℃ / min, the calcination temperature was 320℃, and the calcination time was 5 h to obtain the adsorbent intermediate. During the process, the moist blue litmus paper placed in the tail gas bottle of the tube furnace did not change color. (5) The adsorbent intermediate was loaded into a carbon monoxide adsorption evaluation device, and the temperature was increased at a rate of 3℃ / min. It was subjected to a secondary reduction treatment for 2 h in a nitrogen atmosphere at 300℃, 0.35MPa, and a flow rate of 65mL / min to obtain CO adsorbent A3. The relevant parameters are listed in Table 1. The tail gas of the device was collected and tested with moist blue litmus paper. No discoloration was observed.

[0057] Example 4 CO adsorbent A4 was prepared using the method of Example 1, except that the calcination temperature in step (4) was 390°C. During the entire preparation process, the moist blue litmus paper did not change color. The relevant parameters of CO adsorbent A4 are listed in Table 1.

[0058] Example 5 CO adsorbent A5 was prepared using the method of Example 1, except that the reduction treatment temperature in step (5) was 390°C. During the entire preparation process, the moist blue litmus paper did not change color. The relevant parameters of CO adsorbent A5 are listed in Table 1.

[0059] Example 6 CO adsorbent A6 was prepared using the method of Example 1, with the only difference being that the heating rate in step (4) was 3℃ / min. During the entire preparation process, the moist blue litmus paper did not change color. The relevant parameters of CO adsorbent A6 are listed in Table 1.

[0060] Comparative Example 1 (1) At 25°C, 2.55 g of copper chloride dihydrate was dissolved in 7 mL of deionized water, and 3.0 g of copper acetate monohydrate was added and stirred for 6 min to dissolve, thus obtaining a solution containing the first copper source and the second copper source. The molar ratio of copper chloride dihydrate to copper acetate monohydrate, calculated by Cu element, is 1:1. (2) Add 5 g of activated carbon to the solution in step (1) and let it soak in the solution. Stir at 25°C for 5 min and let it stand for 25 min to obtain the impregnated carrier. (3) The impregnated carrier is placed in a 60℃ oven for 18 hours to dry, and the dried material is obtained; (4) The dried material was placed in a tube furnace under nitrogen protection for the first reduction treatment. The nitrogen flow rate was 65 mL / min, the heating rate was 4℃ / min, the temperature was 300℃, and the time was 6 h to obtain the adsorbent intermediate. During the process, the moist blue litmus paper placed in the tail gas bottle of the tube furnace did not change color. (5) The adsorbent intermediate was loaded into a carbon monoxide adsorption evaluation device, and the temperature was increased at a rate of 3℃ / min. It was subjected to a secondary reduction treatment for 2h in a nitrogen atmosphere at 300℃ and a flow rate of 65mL / min to obtain CO adsorbent D1. The relevant parameters are listed in Table 1. The tail gas of the device was collected and tested with moist blue litmus paper. The moist blue litmus paper turned red.

[0061] Comparative Example 2 CO adsorbent D2 was prepared using the method of Example 1, with the only difference being that the heating rate in step (4) was 10℃ / min; during the preparation process, the moist blue litmus paper turned red, and the relevant parameters of CO adsorbent D2 are listed in Table 1.

[0062] Test characterization The adsorbent intermediates prepared in Examples 1-6 were subjected to XRD tests, and the results are as follows: Figure 1 As shown. According to Figure 1 The adsorption intermediates prepared in Examples 1-6 were in 2 θ =16.1° and 2 θ Peaks are observed at 32.8° and 40.1°, corresponding to the characteristic diffraction peaks of CuCl2 and Cu(CH3COO)2, respectively. θ Peaks were also observed at 28.5° and 47.4°, corresponding to the characteristic diffraction peaks of CuCl, indicating that after the first reduction roasting, some divalent copper was reduced to monovalent copper, and no 0-valent copper was produced.

[0063] XRD tests were performed on the CO adsorbents prepared in Examples 1-6 and Comparative Examples 1-2, and the results are as follows: Figure 2 As shown. According to Figure 2 The CO adsorbents prepared in Examples 1-6 only showed up in 2... θ Peaks are observed at 28.5° and 47.4°, corresponding to the characteristic diffraction peaks of CuCl, indicating that the copper element in the CO adsorbent prepared by the method of this disclosure exists in the monovalent copper form; the CO adsorbents prepared in Comparative Examples 1 and 2 show peaks at 2... θ Weak peaks are observed at 28.5° and 47.4°, corresponding to the characteristic diffraction peaks of CuCl. θ A peak is observed at 43.4°, which corresponds to the characteristic diffraction peak of elemental copper. This indicates that some of the copper element in the CO adsorbents prepared in Comparative Examples 1 and 2 exists in the form of elemental copper, meaning that some of the copper raw materials were excessively reduced to elemental copper.

[0064] XPS tests were performed on the adsorbent intermediates prepared in Examples 1-3, and the results are as follows: Figure 3 As shown. According to Figure 3 It can be seen that the adsorbent intermediate shows two peaks at 952.5 eV and 954.6 eV, representing the Cu(I) and Cu(II) derivatives, respectively. p 1 / 2 The binding energies, with two peaks at 932.7 eV and 934.7 eV, can be attributed to Cu(I) and Cu(II) Cu 2. p 3 / 2 The binding energy.

[0065] Test case Test method for CO dynamic adsorption capacity: The CO adsorbents prepared in Examples 1-6 and Comparative Examples 1-2 were loaded into a fixed-bed reactor, respectively. Hydrogen gas with a CO concentration of 1 ppm was introduced, the adsorption temperature was 40℃, the adsorption pressure was 2.1 MPa, and the volume hourly space velocity was 3000 h⁻¹. -1The concentration of CO in the product hydrogen gas was detected by gas chromatography. When the CO concentration in the product gas exceeded 0.2 ppm, the adsorbent was considered to have broken through. The results are listed in Table 1. The CO adsorption curves of the CO adsorbents prepared in Examples 1-6 and Comparative Examples 1-2 are shown below. Figure 4 As shown.

[0066] Table 1

[0067] Based on the above data, it can be seen that the CO adsorbent prepared by the method disclosed herein does not contain elemental Cu, does not generate Cl2 gas during the preparation process, has a long CO adsorption breakthrough time, and has a high CO adsorption capacity.

[0068] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0069] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0070] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A process for the preparation of a CO adsorbent, characterized in that, The method comprises the following steps: S1, contacting a porous carbon carrier, a first copper source, a second copper source and water to obtain a contacted carrier; S2, performing a first reduction treatment on the contacted carrier under a first inert atmosphere to obtain an adsorbent intermediate; S3, performing a second reduction treatment on the adsorbent intermediate under a second inert atmosphere under a pressurized condition; The first copper source comprises CuCl2; The second copper source comprises Cu(CH3COO)2; In step S1, the molar ratio of the first copper source to the second copper source is (0.9-1.0):(1.0-1.1) in terms of copper element; The temperature rising speed of the first reduction treatment is 5℃ / min or lower.

2. The method of claim 1, wherein, The porous carbon carrier comprises one or more of activated carbon, graphene, carbon and carbon black; The BET specific surface area of the porous carbon support is 1000-2000 m 2 / g, preferably 1600-2000 m 2 / g.

3. The method of claim 1, wherein, In step S1, the contacting conditions comprise a temperature of 25-35℃, a stirring time of 5-8min and a standing time of 25-35min.

4. The method of claim 1, wherein, In step S1, the molar ratio of the first copper source to the second copper source is (0.95-1.0):(1.0-1.05) in terms of copper element; Optionally, the weight ratio of the first copper source, the second copper source and the porous carbon carrier is (1.7-10.2):(2.0-12.0):10.0, preferably (3.4-5.1):(4.0-6.0):10.0; The volume ratio of the water to the porous carbon carrier is (1.0-1.2):

1.

5. The method of claim 1, wherein, Step S1 further comprises performing a drying treatment on the solid-liquid mixture obtained by the contacting to obtain the contacted carrier; The drying treatment conditions comprise a time of 12-24h and a temperature of 60-120℃.

6. The method of claim 1, wherein, In step S2, the first reduction treatment conditions comprise a temperature of 200-390℃, preferably 250-350℃, a time of 2-6h, preferably 4-6h, and a temperature rising speed of 2-5℃ / min, preferably 4-5℃ / min; The first inert atmosphere comprises one or more of helium, argon and nitrogen; The flow rate of the first inert atmosphere is 40-120 mL / min, preferably 50-80 mL / min.

7. The method of claim 1, wherein, In step S3, the second reduction treatment conditions comprise a temperature of 200-390℃, preferably 250-350℃, a time of 1-4h, preferably 2-3h, a pressure of 0.2-0.5MPa, preferably 0.3-0.4MPa, and a temperature rising speed of 2-8℃ / min, preferably 2-3℃ / min; The second inert atmosphere comprises one or more of helium, argon and nitrogen; The flow rate of the second inert atmosphere is 40-120 mL / min, preferably 50-70 mL / min.

8. A CO adsorbent prepared by the method of any one of claims 1-7.

9. The CO adsorbent of claim 8, wherein, The CO adsorbent does not contain elemental Cu; Optionally, the CO adsorbent has a BET specific surface area of 800-1100 m 2 / g, and a pore volume of 0.6-0.8 cm 3 / g; Optionally, the CO adsorbent contains a monovalent copper active component, and the content of the monovalent copper active component is 4-12 mmol / g, preferably 4-6 mmol / g, relative to the total weight of the CO adsorbent.

10. A method of adsorbing CO, characterized by, The method comprises: contacting a CO-containing gas to be treated with the CO adsorbent according to claim 8 or 9.

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