Methanol water reforming hydrogen production method

Abstract

The invention discloses a methanol water reforming hydrogen production method, and relates to the technical field of hydrogen energy preparation, and the method comprises the following steps: 1) catalytic reforming reaction; and 2) separation and purification. The preparation method comprises the following steps: performing nitrogen doping modification on activated carbon by a hydrothermal method to prepare an N-AC carrier; then Co is preferentially anchored to the carrier at low temperature by utilizing the steric hindrance effect of a cobalt-ammonia complex, and a highly dispersed CoxOy active center is formed through thermal decomposition; and finally, co-dipping Cu and Zn precursors, precipitating and reducing to form a Cu-Zn active center, and constructing a Cu-Zn-CoxOy / N-AC bifunctional concerted catalytic system which is used for hydrogen production by reforming methanol and water. After methanol and desalted water are mixed and gasified, the mixture is introduced into a reforming reactor loaded with a Cu-Zn-CoxOy / N-AC catalyst for reaction, generated reformed gas is subjected to cooling and gas-liquid separation and then is purified through a CO adsorption bed and a pressure swing adsorption system, and high-purity hydrogen is obtained.

Description

Technical Field

[0001] This invention relates to the field of hydrogen production technology, and in particular to a method for producing hydrogen by methanol-water reforming. Background Technology

[0002] Hydrogen energy, as a clean and efficient secondary energy source, is an ideal choice for addressing the fossil fuel crisis and environmental pollution. Among them, methanol steam reforming hydrogen production technology is considered a highly promising on-board or distributed hydrogen production solution due to the wide availability of methanol, safe storage and transportation, and relatively low reaction temperature.

[0003] The core of this technology lies in the catalyst. Currently, the MSR catalyst systems researched and applied are mainly copper-zinc-aluminum (Cu-Zn-Al) based catalysts. Their catalytic mechanism primarily depends on Cu... 0 The Cu-Zn catalyst plays a crucial role in the dissociation, adsorption, and reforming of methanol molecules, while ZnO disperses and stabilizes Cu particles to prevent sintering. However, traditional Cu-Zn-based catalysts face several significant technical bottlenecks: First, catalytic activity and hydrogen yield are limited: the MSR process is a complex reaction network, mainly including methanol reforming reaction ( ) and side reaction water-gas shift reaction ( In traditional catalysts, the two reactions compete for Cu active sites. However, due to the relatively slow kinetic rate of the water-gas shift reaction, the intermediate product CO cannot be consumed in time. This not only restricts the overall reaction rate and methanol conversion, but the accumulation of CO also inhibits the forward progress of the methanol reforming main reaction, thus limiting the final hydrogen yield.

[0004] Secondly, the high CO concentration in the product gas leads to exorbitant purification costs: the CO volume fraction in the reformed gas from traditional Cu-Zn catalysts typically reaches 1%-2%, or even higher. High CO concentrations are unacceptable for both fuel cells (requiring CO <10ppm) and other high-purity hydrogen applications. Therefore, existing technologies rely on complex and expensive subsequent purification processes, such as multi-stage pressure swing adsorption (PSA) or large-scale deep CO removal units (e.g., methanation, PROX), which significantly increases system complexity, equipment investment, and operating costs, hindering the large-scale commercial application of this technology.

[0005] Third, catalyst stability and lifespan face challenges: CO generated during the reaction is a chemical poison that easily adsorbs onto Cu active sites, leading to poisoning and deactivation. Simultaneously, Cu particles are prone to migration and sintering under long-term high-temperature reaction conditions, resulting in a reduction of active sites and rapid degradation of catalyst performance.

[0006] To address these issues, researchers have tried various methods, such as adding additives (Zr, Ce, etc.) to modify the support or optimizing the preparation process. However, most of these improvements are still limited to modifying a single Cu-Zn active center and have failed to fundamentally change the reaction pathway and thermodynamic limitations.

[0007] Therefore, developing a new type of high-efficiency catalyst that can break the reaction limitations of a single active center, improve methanol conversion and hydrogen yield, and achieve in-situ deep removal of CO in the reactor, thereby significantly reducing the subsequent purification load and cost and extending catalyst life, has become an urgent need and an important direction for the development of methanol-water reforming hydrogen production technology. Summary of the Invention

[0008] The purpose of this invention is to address the shortcomings of existing technologies by proposing a self-healing wear-resistant polyurethane expansion joint composition and its preparation method.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: This invention first proposes a method for producing hydrogen through methanol-water reforming, comprising the following steps: 1) Catalytic reforming reaction Methanol and demineralized water are mixed in a specific ratio and pumped into a vaporizer via a metering pump. After vaporization, the mixture is fed into a reforming reactor, where it is reacted with a Cu-Zn-Co catalyst. x O y Reforming and transformation reactions occur under the action of / N-AC; Reforming reaction of methanol vapor occurs on a Cu-based catalyst: Methanol molecules first undergo dehydrogenation at the catalyst active site (Cu) to produce formaldehyde and carbon monoxide, then react with water to finally decompose completely into CO2 and H2.

[0010] A small amount of carbon monoxide is produced in the reaction. The water-gas shift reaction uses water to convert the toxic CO into CO. x O y The hydrogen is converted into additional CO2 and H2. This increases hydrogen production while reducing CO concentration, thus easing the burden on subsequent purification.

[0011] 2) Separation and purification The reformed gas is cooled to below 40°C by a heat exchanger and then enters a gas-liquid separator. After unreacted water and methanol are separated, it passes through a CO adsorption bed where residual CO is selectively adsorbed. The gas enters the pressure swing adsorption system, where it alternately adsorbs impurities such as CO2 and CH4 to obtain high-purity hydrogen. The Cu-Zn-Co xO y The preparation process of / N-AC catalyst is as follows: Preparation of S1 and N-AC supports After being treated with nitric acid reflux, activated carbon was added to a urea aqueous solution, stirred and sonicated for 30 minutes to ensure thorough mixing and wetting, resulting in a suspension. The suspension was transferred to a reaction vessel, sealed, and placed in an oven to react at 180°C for 12 hours. After naturally cooling to room temperature, open the reactor, filter using a vacuum filtration device, and wash with a large amount of hot deionized water until the filtrate is neutral. Then, vacuum dry at 80°C for 12 hours. The activated carbon N-AC was obtained by calcining at 600℃ for 2 hours in a nitrogen atmosphere and then cooling it. Nitrogen-modified activated carbon (N-AC) not only forms the framework for loading active components, but also provides a huge surface area, allowing Cu, Zn, and Co to be highly dispersed and exposing more active sites. The incorporated nitrogen atoms introduce alkaline sites to the carrier surface, which have a stronger adsorption and activation capacity for H2O molecules in the reactants. While promoting the water-gas shift reaction, the lone pair electrons on the nitrogen atoms can interact strongly with metal ions, better anchoring these metals during the preparation process and preventing their migration and aggregation, thereby forming smaller and more stable metal particles.

[0012] Support of S2 and Co catalysts Co(NH3)6Cl3 was dissolved in an ice-water mixture, placed in N-AC, and allowed to stand in an ice-water bath for 12 hours for immersion. The support was then removed, its surface was rapidly rinsed with ice water, and vacuum dried at 60°C for 12 hours. Finally, in a tube furnace under an Ar atmosphere, the temperature was raised to 200°C and held for 2 hours to obtain Co. x O y / N-AC; Co(NH3)6Cl3 is a very large molecule with significant steric hindrance, which allows it to remain stable in a low-temperature ice-water bath. This ensures that the Co precursor is slowly and uniformly dispersed inside and outside the pores of N-AC, preventing excessively high local concentrations that could lead to the formation of large particles. Heating in an inert atmosphere causes the cobalt amine complex to decompose, generating highly dispersed cobalt oxide nanoparticles that firmly adhere to N-AC.

[0013] However, since Co has a +2 and +3 valence in cobalt oxides and O has a -2 valence, and the molar quantity is not fixed, it is actually a mixture of CoO and Co3O4.

[0014] Supported S3 and Cu-Zn catalysts Dissolve Cu(NO3)2·3H2O and Zn(NO3)2·6H2O in deionized water and impregnate Co. x O y / N-AC, let stand at room temperature for 12 hours to ensure full adsorption; After the second impregnation, the carrier was transferred to the reaction vessel, Na2CO3 aqueous solution was added, and the vessel was sealed and gently stirred at 60°C for 2 hours to ensure complete precipitation. The vessel was then filtered, washed repeatedly with deionized water, and dried at 80°C for 12 hours. Add Na2CO3 solution to Cu 2+ and Zn 2+ Ions co-precipitate on the carrier surface in the form of basic carbonates, which helps to form a precursor with uniform composition and good dispersion.

[0015] The dried sample was placed in a tube furnace with a 5% H2 / N2 mixed gas, and the temperature was slowly increased to 220℃-240℃ and held for 6-8 hours. It was then cooled to room temperature under Ar protection to obtain the catalyst Cu-Zn-Co. x O y / N-AC.

[0016] At a reduction temperature of 220-240℃, CuO is reduced to catalytically active metallic Cu nanoparticles, while the hydrogen reduction temperature of ZnO is generally between 300℃ and 400℃, so it will not be reduced and will exist in the form of oxides. A very small portion may be reduced and will form a galvanic cell with Cu and C, and will be oxidized during discharge to reform ZnO. Copper is the main active center in the methanol steam reforming reaction. It has good dehydrogenation ability, can efficiently catalyze the breaking of CH and OH bonds to generate H2, and guide methanol molecules to convert into the final products CO2 and H2. ZnO, as a structural aid, can prevent the fine Cu nanoparticles from sintering and growing in the high-temperature reaction, thus stabilizing the active center.

[0017] Preferably, in step 1), the molar ratio of methanol to desalinated water is 1:1.2-1.5; The vaporization temperature is 150℃; The reaction temperature of the methanol reforming reactor is 240-280℃, and the pressure is 1.0-1.5MPa.

[0018] Preferably, in step 2), the CO concentration at the outlet of the reformed gas after passing through the CO adsorption bed is ≤500ppm.

[0019] Preferably, in step S1, the activated carbon is activated by reflux treatment with a 2.0 mol / L nitric acid aqueous solution at 150°C for 4 hours; The mass ratio of urea to activated carbon is 1.5-2.5:1; urea participates in the reaction in the form of a 5% (w / w) aqueous solution.

[0020] Preferably, in S2, Co(NH3)6Cl3 participates in the reaction in the form of a 0.1 mol / L aqueous solution; the resulting Cox O y In this context, Co has a +2 and +3 valence, while O has a -2 valence.

[0021] Preferably, in S3, the molar ratio of Cu to Zn is 1.8-2.2:1; and the molar concentration of the added Na2CO3 aqueous solution is 0.2 mol / L.

[0022] The present invention also proposes the application of the aforementioned methanol-water reforming hydrogen production method. Based on this method, a methanol-water on-site hydrogen production machine is made. In the mixed gas after the reaction, the hydrogen content is about 74.5%, the CO2 content is about 24.5%, the CO content is not higher than 1.0%, the single-pass conversion rate of methanol is over 98%, and the unreacted methanol and demineralized water are returned to the raw material system for recycling.

[0023] Compared with the prior art, the beneficial effects of the present invention are: 1. Significantly improves catalytic activity and hydrogen yield. Traditional catalysts typically contain only Cu-Zn components and primarily catalyze reforming reactions. Water-gas shift reactions rely on the same active sites, but their lower efficiency limits the reaction rate.

[0024] The catalyst of this invention is designed to be "Cu-Zn+Co". x O y The Cu-Zn site exhibits a dual-active-center structure. The Cu-Zn site efficiently catalyzes the CH3OH reforming reaction, while the adjacent Co site… x O y The site efficiently catalyzes the CO oxidation reaction. The two reactions proceed synergistically at the nanoscale, breaking the reaction limitations of traditional single active sites, making the reaction network more fluid, and reducing the degree of CO poisoning of copper-based catalysts.

[0025] The water-gas shift reaction consumes the CO produced by the reforming reaction. According to Le Chatelier's principle, this promotes the forward progress of the methanol reforming reaction, significantly improving the methanol conversion rate and the total hydrogen yield.

[0026] 2. Deep CO removal significantly reduces purification load and cost. The CO concentration at the outlet of traditional Cu-Zn based catalysts is usually 1-2% or even higher. High CO concentrations place a heavy burden on the subsequent pressure swing adsorption system, and if the product gas is used in fuel cells, an extremely complex and expensive deep purification device is required.

[0027] Co x O yIt is a highly efficient CO reaction catalyst that can directly convert most of the CO in the reactor. Through this directional catalytic design, the CO concentration in the gas flowing out of the reforming reactor is reduced to below 500 ppm, which greatly reduces the load on the subsequent CO adsorption bed and thus extends its life. More importantly, it makes the feed gas quality of the PSA system extremely high, and the PSA only needs to mainly adsorb CO2 and CH4.

[0028] 3. Rational catalyst design Unlike traditional Cu-Zn catalysts that rely on a single active site, this invention precisely constructs bifunctional active sites through stepwise loading. First, utilizing the steric hindrance effect of the macromolecular cobalt-ammonia complex at low temperatures, it is preferentially and independently anchored on the surface of the large and medium pores of the N-AC support, avoiding competition with subsequent metals for positioning and ensuring the optimal placement of Co. x O y Efficient formation of water-gas shift activity centers.

[0029] Subsequently, the Cu-Zn precursor was loaded using a co-impregnation method, which mixed the two at the atomic level and concentrated them at other sites on the support, laying the foundation for constructing a Cu-Zn alloy interface for synergistic catalytic methanol reforming. Nitrogen atoms, as electron anchoring sites, interact strongly with the active metal components, greatly improving the dispersion and anti-sintering ability of Cu, Zn, and Co particles, ensuring the high stability and long life of the catalyst. Detailed Implementation

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0031] The purity and manufacturers of the various drugs used in the experiment are shown in Table 1. Table 1. Raw Material Drug Information Preparation Example 1: Preparation of S1 and N-AC supports After being treated with nitric acid reflux, activated carbon was added to a urea aqueous solution, stirred and sonicated for 30 minutes to ensure thorough mixing and wetting, resulting in a suspension. The suspension was transferred to a reaction vessel, sealed, and placed in an oven to react at 180°C for 12 hours. After naturally cooling to room temperature, open the reactor, filter using a vacuum filtration device, and wash with a large amount of hot deionized water until the filtrate is neutral. Then, vacuum dry at 80°C for 12 hours. The activated carbon N-AC was obtained by calcining at 600℃ for 2 hours in a nitrogen atmosphere and then cooling it. Support of S2 and Co catalysts Co(NH3)6Cl3 was dissolved in an ice-water mixture, placed in N-AC, and allowed to stand in an ice-water bath for 12 hours for immersion. The support was then removed, its surface was rapidly rinsed with ice water, and vacuum dried at 60°C for 12 hours. Finally, in a tube furnace under an Ar atmosphere, the temperature was raised to 200°C and held for 2 hours to obtain Co. x O y / N-AC; Supported S3 and Cu-Zn catalysts Dissolve Cu(NO3)2·3H2O and Zn(NO3)2·6H2O in deionized water and impregnate Co. x O y / N-AC, let stand at room temperature for 12 hours to ensure full adsorption; After the second impregnation, the carrier was transferred to the reaction vessel, Na2CO3 aqueous solution was added, and the vessel was sealed and gently stirred at 60°C for 2 hours to ensure complete precipitation. The vessel was then filtered, washed repeatedly with deionized water, and dried at 80°C for 12 hours. The dried sample was placed in a tube furnace with a 5% H2 / N2 mixed gas, and the temperature was slowly increased to 220℃-240℃ and held for 6-8 hours. It was then cooled to room temperature under Ar protection to obtain the catalyst Cu-Zn-Co. x O y / N-AC.

[0032] In step S1, the activated carbon is activated by reflux treatment with a 2.0 mol / L nitric acid aqueous solution at 150°C for 4 hours; The mass ratio of urea to activated carbon is 1.5:1; urea participates in the reaction in the form of a 5% (w / w) aqueous solution.

[0033] In S2, Co(NH3)6Cl3 participates in the reaction in the form of a 0.1 mol / L aqueous solution; the resulting Co x O y In this context, Co has a +2 and +3 valence, while O has a -2 valence.

[0034] In S3, the molar ratio of Cu to Zn is 2.2:1; the molar concentration of the added Na2CO3 aqueous solution is 0.2 mol / L.

[0035] Preparation Example 2: The experimental method is the same as that in Preparation Example 1, but the mass ratio of urea to activated carbon in S1 is 2:1; and the molar ratio of Cu to Zn in S3 is 2:1.

[0036] Preparation Example 3: The experimental method is the same as that used in Preparation Example 1, but the mass ratio of urea to activated carbon in S1 is 2.5:1; and the molar ratio of Cu to Zn in S3 is 1.8:1.

[0037] Example 1: A method for producing hydrogen from methanol-water reforming includes the following steps: 1) Catalytic reforming reaction Methanol and demineralized water were mixed in a specific ratio and pumped into a vaporizer via a metering pump. After vaporization, the mixture was fed into a reforming reactor to prepare the Cu-Zn-Co catalyst produced in Example 1. x O y Reforming and transformation reactions occur under the action of / N-AC; 2) Separation and purification The reformed gas is cooled to below 40°C by a heat exchanger and then enters a gas-liquid separator. After unreacted water and methanol are separated, it passes through a CO adsorption bed where residual CO is selectively adsorbed. The gas enters the pressure swing adsorption system, where it alternately adsorbs impurities such as CO2 and CH4 to obtain high-purity hydrogen. The Cu-Zn-Co x O y The preparation process of / N-AC catalyst is as follows: Preparation of S1 and N-AC supports After being treated with nitric acid reflux, activated carbon was added to a urea aqueous solution, stirred and sonicated for 30 minutes to ensure thorough mixing and wetting, resulting in a suspension. The suspension was transferred to a reaction vessel, sealed, and placed in an oven to react at 180°C for 12 hours. After naturally cooling to room temperature, open the reactor, filter using a vacuum filtration device, and wash with a large amount of hot deionized water until the filtrate is neutral. Then, vacuum dry at 80°C for 12 hours. The activated carbon N-AC was obtained by calcining at 600℃ for 2 hours in a nitrogen atmosphere and then cooling it. Support of S2 and Co catalysts Co(NH3)6Cl3 was dissolved in an ice-water mixture, placed in N-AC, and allowed to stand in an ice-water bath for 12 hours for immersion. The support was then removed, its surface was rapidly rinsed with ice water, and vacuum dried at 60°C for 12 hours. Finally, in a tube furnace under an Ar atmosphere, the temperature was raised to 200°C and held for 2 hours to obtain Co. x O y / N-AC; Supported S3 and Cu-Zn catalysts Dissolve Cu(NO3)2·3H2O and Zn(NO3)2·6H2O in deionized water and impregnate Co. x O y / N-AC, let stand at room temperature for 12 hours to ensure full adsorption; After the second impregnation, the carrier was transferred to the reaction vessel, Na2CO3 aqueous solution was added, and the vessel was sealed and gently stirred at 60°C for 2 hours to ensure complete precipitation. The vessel was then filtered, washed repeatedly with deionized water, and dried at 80°C for 12 hours. The dried sample was placed in a tube furnace with a 5% H2 / N2 mixed gas, and the temperature was slowly increased to 220℃-240℃ and held for 6-8 hours. It was then cooled to room temperature under Ar protection to obtain the catalyst Cu-Zn-Co. x O y / N-AC.

[0038] In step 1), the molar ratio of methanol to deionized water is 1:1.2; The vaporization temperature is 150℃; The reaction temperature of the methanol reforming reactor is 240-280℃, and the pressure is 1.0-1.5MPa.

[0039] In step 2), after the reformed gas passes through the CO adsorption bed, the outlet CO concentration is ≤500ppm.

[0040] Example 2: The implementation method is the same as in Example 1, but the catalyst Cu-Zn-Co produced in Preparation Example 2 is used. x O y / N-AC; In 1), the molar ratio of methanol to deionized water is 1:1.35.

[0041] Example 3: The implementation method is the same as in Example 1, but the catalyst Cu-Zn-Co produced in Preparation Example 1 is used. x O y / N-AC; In step 1), the molar ratio of methanol to deionized water is 1:1.5.

[0042] Unlike the embodiments, the following comparative experiments were also designed: Comparative Example 1: The formulation and experimental method are the same as those in Preparation Example 2, but the mass ratio of urea to activated carbon in S1 is 1:1; Comparative Example 2: The formulation and experimental method are the same as those in Preparation Example 2, but the mass ratio of urea to activated carbon in S1 is 4:1; Comparative Example 3: The formulation and experimental method are the same as those in Preparation Example 2, but in S3, the molar ratio of Cu to Zn is 1:1. Comparative Example 4: The formulation and experimental method are the same as those in Preparation Example 2, but in S3, the molar ratio of Cu to Zn is 4:1.

[0043] The purity of hydrogen prepared according to the test scheme of GB / T 29729, the selectivity, mechanical strength and lifetime of catalysts tested according to HG / T 5568-2019, and the corresponding results are summarized in Table 2: Table 2. Performance test data of the methanol-water reforming method for hydrogen production. Data Analysis: Comparative Examples 2, 1, and 2 show that a moderate amount of nitrogen doping can create abundant nitrogen-containing functional groups on the surface of activated carbon, serving as metal anchoring sites and enhancing metal dispersion, without excessively damaging the pore structure of the activated carbon. Therefore, Example 2 exhibits the highest H2 purity, the lowest CO selectivity, the best mechanical strength, and the longest lifespan.

[0044] In Comparative Example 1, insufficient nitrogen doping and a 1:1 mass ratio of urea to activated carbon resulted in surface defects and insufficient anchoring points on the support. The active metals (Co, Cu, Zn) were poorly dispersed and prone to agglomeration, leading to a reduction in active sites, decreased catalytic activity and selectivity, and a shortened lifespan.

[0045] In Comparative Example 2, the nitrogen doping was excessive, with a urea to activated carbon mass ratio of 4:1. The excess urea would generate a large amount of nitrogen-containing gas and leave a large amount of amorphous carbon during the high-temperature hydrothermal and calcination process, which would block the micropores and mesopores of the activated carbon, resulting in a decrease in specific surface area and an increase in mass transfer resistance. At the same time, the excess surface nitrogen species would cover some active sites, resulting in a catalyst with acceptable initial activity but increased by-product CO, decreased mechanical strength, and poor stability.

[0046] Comparative Examples 2, 3, and 4 show that a Cu / Zn molar ratio of 2:1 is a common optimized value for the Cu / Zn ratio in classic Cu-Zn-Al catalysts. Although the matrix of the catalyst in this invention is not alumina, it still involves methanol reforming via Cu. The main role of ZnO is to disperse and stabilize Cu particles, preventing sintering. A 2:1 ratio forms the optimal Cu-ZnO interface, synergistically promoting the methanol-water reforming reaction and suppressing side reactions. Therefore, it exhibits the lowest CO selectivity and the longest lifetime.

[0047] In Comparative Example 3, the Cu / Zn molar ratio was 1:1, resulting in a relatively high amount of ZnO. This excess ZnO covered some of the Cu active sites, leading to a decrease in overall catalytic activity. Although the mechanical strength was acceptable, the H2 yield and CO selectivity were not as good as in the examples.

[0048] In Comparative Example 4, the Cu / Zn molar ratio was 4:1. The excessively high Cu content made it difficult for ZnO to effectively disperse so many Cu particles, leading to easy sintering and agglomeration of the Cu particles. Large Cu particles act as active sites for side reactions and CO generation, thus causing a sharp increase in CO selectivity to 3.20% in Comparative Example 4, severely impacting hydrogen purity. Simultaneously, the sintered Cu particles were unstable, resulting in rapid catalyst deactivation and a significantly shortened catalyst lifetime.

[0049] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for producing hydrogen through methanol-water reforming, characterized in that, Includes the following steps: 1) Catalytic reforming reaction Methanol and demineralized water are mixed in a specific ratio and pumped into a vaporizer via a metering pump. After vaporization, the mixture is fed into a reforming reactor, where it is reacted with a Cu-Zn-Co catalyst. x O y Reforming and transformation reactions occur under the action of / N-AC; 2) Separation and purification The reformed gas is cooled to below 40°C by a heat exchanger and then enters a gas-liquid separator. After unreacted water and methanol are separated, it passes through a CO adsorption bed where residual CO is selectively adsorbed. The gas enters the pressure swing adsorption system, where it alternately adsorbs impurities such as CO2 and CH4 to obtain high-purity hydrogen. The Cu-Zn-Co x O y The preparation process of / N-AC catalyst is as follows: Preparation of S1 and N-AC supports After being treated with nitric acid reflux, activated carbon is added to a urea aqueous solution, stirred and sonicated for 30 minutes to ensure thorough mixing and wetting, resulting in a suspension. The suspension is then transferred to a reaction vessel, sealed, and placed in an oven for high-temperature reaction at 180°C. After naturally cooling to room temperature, open the reaction vessel, filter using a vacuum filtration device, and wash with a large amount of hot deionized water until the filtrate is neutral, then vacuum dry. The activated carbon N-AC was obtained by calcining at 600℃ for 2 hours in a nitrogen atmosphere and then cooling it. Support of S2 and Co catalysts Co(NH3)6Cl3 was dissolved in an ice-water mixture, and then placed in N-AC. The mixture was allowed to stand in an ice-water bath until fully impregnated. The carrier was then removed, its surface was rapidly rinsed with ice water, and vacuum dried. In a tube furnace under an inert atmosphere, the temperature was raised to 200°C and held for 2 hours to obtain Co. x O y / N-AC; Supported S3 and Cu-Zn catalysts Dissolve Cu(NO3)2·3H2O and Zn(NO3)2·6H2O in deionized water and impregnate Co. x O y / N-AC, let stand at room temperature to ensure full adsorption; After the second impregnation, the carrier was transferred to the reaction vessel, Na2CO3 aqueous solution was added, and the vessel was sealed and gently stirred at 60°C for 2 hours to ensure complete precipitation. The vessel was then filtered, washed repeatedly with deionized water, and dried at 80°C for 12 hours. The dried sample was placed in a tube furnace with a 5% H2 / N2 mixed gas, and the temperature was slowly increased to 220℃-240℃ and held for 6-8 hours. It was then cooled to room temperature under Ar protection to obtain the catalyst Cu-Zn-Co. x O y / N-AC.

2. The method for producing hydrogen from methanol-water reforming according to claim 1, characterized in that: In step 1), the molar ratio of methanol to desalinated water is 1:1.2-1.5; The vaporization temperature is 150℃; The reaction temperature of the methanol reforming reactor is 240-280℃, and the pressure is 1.0-1.5MPa.

3. The method for producing hydrogen from methanol-water reforming according to claim 1, characterized in that: In step 2), after the reformed gas passes through the CO adsorption bed, the outlet CO concentration is ≤500ppm.

4. The method for producing hydrogen from methanol-water reforming according to claim 1, characterized in that: In step S1, the activated carbon is activated by reflux treatment with a 2.0 mol / L nitric acid aqueous solution at 150°C for 4 hours; The mass ratio of urea to activated carbon is 1.5-2.5:1; urea participates in the reaction in the form of a 5% (w / w) aqueous solution.

5. The method for producing hydrogen from methanol-water reforming according to claim 1, characterized in that: In S2, Co(NH3)6Cl3 participates in the reaction in the form of a 0.1 mol / L aqueous solution; the resulting Co x O y In this context, Co has a +2 and +3 valence, while O has a -2 valence.

6. The method for producing hydrogen from methanol-water reforming according to claim 1, characterized in that: In S3, the molar ratio of Cu to Zn is 1.8-2.2:1; the molar concentration of the added Na2CO3 aqueous solution is 0.2 mol / L.

7. The application of the methanol-water reforming method for hydrogen production according to any one of claims 1-6, characterized in that, Using this method, a methanol-water on-site hydrogen generator was manufactured. The mixed gas after the reaction contained approximately 74.5% hydrogen, approximately 24.5% CO2, and no more than 1.0% CO. The single-pass conversion rate of methanol was over 98%, and the unreacted methanol and demineralized water were returned to the raw material system for recycling.

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