Non-noble metal catalyst for hydrogen production by steam reforming of small molecular alcohols and preparation method of non-noble metal catalyst

Abstract

The invention belongs to the technical field of catalysts for hydrogen production by reforming, and relates to a non-noble metal catalyst for hydrogen production by steam reforming of small molecular alcohols as well as a preparation method and application of the non-noble metal catalyst. The non-noble metal catalyst is composed of a carrier and active metal loaded on the carrier; wherein the active metal comprises a non-noble metal and / or a rare earth metal, the non-noble metal comprises cobalt and / or nickel, and the rare earth metal comprises lanthanum and / or cerium. The preparation method of the non-noble metal catalyst comprises the following steps: firstly, dipping an active metal salt solution into a carrier, then sequentially drying and calcining to prepare a precursor of the catalyst, and then carrying out in-situ reduction on the precursor of the catalyst in a small molecular alcohol reforming hydrogen production reaction environment to prepare the catalyst. By optimizing the composition of the loaded active metal, the prepared catalyst has the characteristics of high low-temperature catalytic activity, good stability, high hydrogen production efficiency and strong applicability.

Description

Technical Field

[0001] The invention belongs to the technical field of reforming hydrogen production catalysts and relates to a non-precious metal catalyst for hydrogen production by steam reforming of small molecule alcohols and a preparation method and application thereof. Background Art

[0002] As the global energy situation becomes increasingly complex, energy strategy and energy reserves have gradually become an important guarantee for national progress and development. my country's energy structure is characterized by "rich in coal, poor in oil and little gas". Although the output of coal, oil and natural gas in my country has increased year by year, my country's energy production structure is still mainly coal-based, and the consumption structure is also mainly coal-based. With the continuous progress and innovation of science and technology and the complexity of the energy situation, my country has begun to vigorously promote the development of new green energy, gradually replacing fossil energy with clean energy, reducing greenhouse gases and NO x Hydrogen is an ideal clean green energy source. It only produces water during combustion and does not emit CO2 and NO. x As a substitute for conventional fossil energy, the research and development of hydrogen energy has become an important direction of world energy development.

[0003] According to its production source and carbon emissions during the production process, hydrogen is divided into "grey hydrogen", "blue hydrogen" and "green hydrogen". Hydrogen obtained from fossil fuels is "grey hydrogen"; hydrogen produced with a carbon capture system on the basis of "grey hydrogen" is "blue hydrogen", and its carbon emissions are significantly lower than "grey hydrogen", but it is necessary to develop supporting processes for the utilization of carbon dioxide; hydrogen produced using renewable energy and renewable raw materials is "green hydrogen", which produces almost no carbon emissions throughout its life cycle.

[0004] At present, it is believed that the main sources of hydrogen in the actual production process are fossil fuels and biomass raw materials, among which biomass raw materials mainly include waste biomass, bioalcohols, etc.

[0005] China is the world's largest methanol producer, accounting for 60% of the world's methanol production capacity. Methanol is abundant in sources, low in cost, and easy to store and transport as a liquid at room temperature and pressure. Compared with other hydrogen production methods such as industrial hydrogen production, methanol hydrogen production has lower energy consumption and cost.

[0006] Ethanol has the advantages of wide sources, easy storage and transportation, and renewable. Using ethanol as a raw material to produce hydrogen through steam reforming reaction has the advantages of simple process, high hydrogen production efficiency, and the output of hydrogen is green hydrogen. However, the existing ethanol steam reforming hydrogen production reaction temperature is high (usually around 600°C) and energy consumption is high, making it difficult to achieve industrialization. Summary of the invention

[0007] One of the purposes of the present invention is to provide a non-precious metal catalyst for low-temperature steam reforming of small molecule alcohols to produce hydrogen in response to the problems existing in the prior art. The catalyst has high activity and selectivity, good stability, and requires a small amount of catalyst. It can also efficiently catalyze the steam reforming of small molecule alcohols to produce hydrogen under low temperature conditions (methanol to hydrogen can be as low as 240°C, and ethanol to hydrogen can be as low as 400°C).

[0008] The second object of the present invention is to provide a method for preparing the above-mentioned catalyst, which can improve the activity, selectivity and stability of the catalyst, reduce the amount of loaded active metal, and at the same time reduce the reaction temperature of small molecule alcohol reforming hydrogen production (methanol hydrogen production can be as low as 240°C, ethanol hydrogen production can be as low as 400°C), bringing huge environmental and economic benefits to society.

[0009] To this end, the first aspect of the present invention provides a non-precious metal catalyst for hydrogen production by warm steam reforming of small molecule alcohols, which is composed of a carrier and an active metal loaded on the carrier; wherein the active metal includes non-precious metals and / or rare earth metals, the non-precious metals include cobalt and / or nickel, and the rare earth metals include lanthanum and / or cerium.

[0010] In the present invention, the material of the carrier includes one or more of olivine, white corundum, magnesium oxide, lanthanum oxide, and cerium oxide.

[0011] In some embodiments of the present invention, the loading amount of the active metal is 1 wt% to 30 wt%.

[0012] Preferably, when the active metal comprises a non-noble metal and a rare earth metal, the molar ratio of the non-noble metal to the rare earth metal in the catalyst is ≥1.0, more preferably ≥1.5.

[0013] The second aspect of the present invention provides a method for preparing a non-precious metal catalyst for hydrogen production by steam reforming of small molecule alcohols, which comprises:

[0014] Step A, impregnating the carrier with an active metal salt aqueous solution, and then drying and calcining the carrier loaded with the active metal salt in sequence to obtain a carrier loaded with an active metal oxide;

[0015] Step B, in situ reducing the carrier loaded with active metal oxide in a reaction environment for hydrogen production by reforming small molecule alcohols to obtain a non-precious metal catalyst for hydrogen production by steam reforming small molecule alcohols.

[0016] In the present invention, the active metal salt aqueous solution comprises one or more of cobalt, nickel, lanthanum and cerium salt solutions.

[0017] In the present invention, the material of the carrier includes one or more of olivine, white corundum, magnesium oxide, lanthanum oxide and cerium oxide.

[0018] According to the present invention, in the carrier loaded with active metal oxide, the loading amount of active metal oxide is 1wt% to 30wt%, and the mass fraction of the carrier is 70wt% to 99wt%.

[0019] In some embodiments of the present invention, in step A, the drying temperature is 60 to 200° C.; and / or the drying time is 1 to 8 hours.

[0020] In some embodiments of the present invention, in step A, the calcination is performed three times; wherein the first calcination is a temperature-increasing calcination, the temperature of the first calcination is 100-500°C, the time of the first calcination is 20-60min, and the heating rate of the first calcination is 3°C / min; the second calcination is a temperature-increasing calcination, the temperature of the second calcination is 500-800°C, the time of the second calcination is 10-30min, and the heating rate of the second calcination is 20°C / min; the third calcination is a constant temperature calcination, the temperature of the third calcination is 750-1000°C, and the time of the second calcination is 1-6h.

[0021] According to the present invention, in step B, the small molecule alcohol steam reforming hydrogen production reaction environment is formed by introducing a small molecule alcohol solution with a concentration of 1 wt % to 50 wt % at a flow rate of 0.001 to 0.1 mL / min.

[0022] In some embodiments of the present invention, the temperature of the in-situ reduction is 200-800° C., and the time of the in-situ reduction is 20-100 min.

[0023] The second aspect of the present invention provides the use of the non-precious metal catalyst as described in the first aspect of the present invention or the non-precious metal catalyst prepared by the preparation method as described in the second aspect of the present invention in hydrogen production by steam reforming of small molecule alcohols.

[0024] In some embodiments of the present invention, the temperature of the small molecule alcohol steam reforming hydrogen production is 400-800°C, and the gas hourly space velocity (GHSV) is 4000-20000h -1 .

[0025] The present invention provides a method for preparing a highly efficient non-precious metal catalyst for steam reforming of small molecule alcohols to produce hydrogen. The present invention first impregnates a metal salt aqueous solution (e.g., a metal nitrate aqueous solution) into a carrier, and then sequentially dries and calcines to obtain a catalyst precursor, and then in-situ reduces the catalyst precursor in a small molecule alcohol reforming hydrogen production reaction environment to obtain a non-precious metal catalyst. The present invention optimizes the composition of loaded active metals, and the obtained catalyst has the characteristics of high low-temperature catalytic activity, good stability, high hydrogen production efficiency, and strong applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be further described in detail below in conjunction with the accompanying drawings:

[0027] Figure 1 This is a diagram of the catalyst operating life experiment.

[0028] Figure 2 This is the SEM image of the catalyst after running for 2000 hours, where the left side is 1 μm and the right side is 200 nm.

[0029] Figure 3 This is the thermogravimetric analysis (TG) diagram of the catalyst. DETAILED DESCRIPTION

[0030] To make the present invention easy to understand, the present invention will be described in detail below in conjunction with the accompanying drawings and examples. However, before describing the present invention in detail, it should be understood that the present invention is not limited to the specific embodiments described. It should also be understood that the terms used herein are only for describing specific embodiments and are not intended to be limiting.

[0031] Where a numerical range is provided, it is understood that each intervening value between the upper and lower limits of the range and any other specified or intervening values ​​in the specified range is encompassed within the present invention. The upper and lower limits of these smaller ranges may be independently included in the smaller ranges and are also encompassed within the present invention, subject to any explicitly excluded limits in the specified ranges. Where a specified range includes one or two limits, ranges excluding either or both of those included limits are also encompassed within the present invention.

[0032] Unless otherwise defined, all terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, preferred methods and materials are now described.

[0033] I. Terminology

[0034] The term "equal volume impregnation method" as used herein is a method for preparing a supported catalyst, wherein the volume of the impregnation liquid is equal to the pore volume of the solid support, so that the impregnation liquid can completely enter the pores of the support. This method can conveniently control the loading amount of the active component, and the loading amount is easy to calculate.

[0035] The term "low-temperature steam reforming" as used in the present invention refers to steam reforming carried out at a temperature of 200 to 500°C.

[0036] The term "small molecule alcohols" used in the present invention refers to small molecule alcohol compounds, including methanol and ethanol.

[0037] The term "water" in the present invention, unless otherwise specified or limited, refers to deionized water, distilled water or ultrapure water.

[0038] As used herein, the terms "about", "approximately", "substantially" and "substantially", when used in conjunction with a range of an element, concentration, temperature or other physical or chemical property or characteristic, cover variations that may exist in the upper and / or lower limits of the range of the property or characteristic, including variations caused, for example, by rounding, measurement method or other statistical variations. For example, as used herein, with respect to numerical values ​​of amount, weight, etc., "about" is defined as all numerical values ​​plus or minus 1% of each specific value, for example, the term "about 10%" should be understood as "9% to 11%".

[0039] II. Implementation Plan

[0040] As mentioned above, the existing ethanol steam reforming hydrogen production reaction temperature is relatively high (usually reacting at about 600°C), consumes a lot of energy, and is difficult to achieve industrialization; in view of this, the inventors have conducted extensive research on ethanol steam reforming hydrogen production catalysts.

[0041] The inventors have discovered that a non-precious metal catalyst can be prepared by replacing traditional precious metals with non-precious metals such as cobalt, nickel, lanthanum and cerium. The catalyst has high activity and selectivity for ethanol steam reforming to produce hydrogen, good stability, and low dosage. The catalyst can also efficiently catalyze ethanol steam reforming to produce hydrogen under low temperature conditions (minimum 400°C for ethanol and minimum 240°C for methanol).

[0042] The method for preparing the high-efficiency non-precious metal catalyst for hydrogen production by steam reforming of small molecule alcohols involved in the present invention comprises the following steps:

[0043] A, impregnating a carrier of the mass required for the equal volume impregnation process with a saturated active metal salt aqueous solution, and then drying and calcining the carrier loaded with the metal salt in sequence to obtain a carrier loaded with active metal oxide;

[0044] B. In situ reduction of a carrier loaded with active metal oxides in a reaction environment for hydrogen production by reforming of small molecule alcohols is performed to obtain a non-precious metal catalyst for hydrogen production by steam reforming of small molecule alcohols.

[0045] Those skilled in the art should understand that the volume of the carrier in the present invention can be obtained by converting the mass and density.

[0046] In the present invention, the active metal salt aqueous solution in step A contains one or more of cobalt, nickel, lanthanum and cerium salt solutions; the inventors have found that the active sites formed by cobalt and nickel non-precious metals can adsorb and catalyze small molecule alcohol molecules to react; the combination formed by lanthanum and cerium rare earth metal oxides can reduce catalyst carbon deposition. Since catalyst carbon deposition often occurs at low temperatures, the non-precious metal catalyst prepared by the present invention is particularly suitable for low-temperature small molecule alcohol reforming hydrogen production reactions, for example, methanol reforming hydrogen production reactions at temperatures below 300°C and ethanol reforming hydrogen production reactions at temperatures below 600°C.

[0047] Based on the above, it is not difficult to understand that the active metal salt in the brine solution in the above step A preferably includes one or more of cobalt salts, nickel salts, lanthanum salts and cerium salts, and is further preferably a cobalt salt, a nickel salt, a cerium salt compound; the active metal salt is preferably one or more of nitrates, sulfites, ammonium sulfites, chlorides, ammonia nitrates and oxalates, wherein the molar ratio of nickel, cobalt (non-precious metals) to lanthanum, cerium (rare earth metals) is preferably greater than or equal to 1.0, further preferably greater than or equal to 1.5, and more preferably greater than or equal to 2.5; studies have found that at such a ratio, the catalyst economy and catalytic performance such as catalytic activity and stability are ideal.

[0048] Preferably, the material of the carrier in step A includes one or more of olivine, white corundum (the main component is aluminum oxide (Al2O3)), magnesium oxide, lanthanum oxide and cerium oxide. Studies have found that olivine contains large gaps in the lattice to load active metals, the Lewis acid sites contained in aluminum oxide can adsorb oxygen atoms in the raw materials, and cerium oxide can provide an oxygen source for the reaction process.

[0049] Preferably, in step A, the process of impregnating the carrier with the active metal salt uses an equal volume impregnation method, which is completed by contacting a dry carrier with an aqueous solution of the active metal salt.

[0050] In the present invention, the specific steps of the equal volume impregnation method are:

[0051] (1) Weigh the required active metal salt and carrier;

[0052] (2) preparing active metal salt solution;

[0053] (3) slowly adding a carrier to an active metal salt solution to obtain a carrier loaded with an active metal salt;

[0054] (4) Allowing the carrier loaded with the active metal salt described in step (3) to stand and then dry.

[0055] In the present invention, the drying temperature in step A is preferably 60 to 200° C., more preferably 70 to 180° C., more preferably 75 to 150° C., and the drying time is preferably 1 to 8 hours, more preferably 2 to 7.5 hours, more preferably 3 to 6 hours.

[0056] In the present invention, in step A, the calcination is a commonly used three-stage calcination in a tubular furnace. The first calcination is a dynamic temperature rise calcination, the temperature of the first calcination is 100-500°C, preferably 120-450°C, more preferably 180-400°C, the time of the first calcination is 20-60min, and the heating rate of the first calcination is 3°C / min; the second calcination is a dynamic temperature rise calcination, the temperature of the second calcination is 500-800°C, the time of the second calcination is 10-30min, and the heating rate of the second calcination is 20°C / min; the third calcination is a constant temperature calcination, the temperature of the third calcination is 750-1000°C, preferably 780-950°C, more preferably 800-900°C, the time of the third calcination is 1-12h, preferably 2-11h, more preferably 2.5-10h, and the time of the third calcination is 1-6h.

[0057] The non-precious metal catalyst for low-temperature steam reforming of small molecule alcohols to produce hydrogen prepared by the above method in the present invention is composed of a carrier and an active metal loaded on the carrier; wherein the active metal includes a non-precious metal and / or a rare earth metal, the non-precious metal includes cobalt and / or nickel, and the rare earth metal includes lanthanum and / or cerium.

[0058] In some embodiments of the present invention, the loading amount of the active metal is 0.1 wt% to 30 wt%.

[0059] Preferably, when the active metal includes a non-precious metal and a rare earth metal, the molar ratio of the non-precious metal to the rare earth metal in the catalyst is ≥1.0, more preferably ≥1.5, and even more preferably ≥2.5.

[0060] Those skilled in the art should understand that the non-precious metal catalyst for low-temperature steam reforming of small molecule alcohols to produce hydrogen prepared by the above method can be effectively used at relatively low temperatures (below 500°C) and shows very little carbon deposition at 400-800°C; at the same time, the catalyst can also operate within a large temperature window, thereby achieving efficient reforming of ethanol and first- and second-generation bioethanol to produce hydrogen.

[0061] The application of the above-mentioned non-precious metal catalyst or the non-precious metal catalyst prepared by the above-mentioned preparation method in the steam reforming of small molecule alcohols to produce hydrogen can be understood as a method for steam reforming of small molecule alcohols to produce hydrogen using the above-mentioned non-precious metal catalyst or the non-precious metal catalyst prepared by the above-mentioned preparation method.

[0062] In some embodiments of the present invention, the temperature of the steam reforming of small molecule alcohols to produce hydrogen is 200-800°C, and the gas hourly space velocity (GHSV) is 4000-20000h -1 .

[0063] At present, the general reaction temperature for obtaining high hydrogen yield by ethanol reforming hydrogen in the industry is above 600°C. When used for a short or long time under high-temperature medium working conditions greater than 550°C, heat-resistant steel with better heat resistance should be used, which makes ethanol steam reforming hydrogen production difficult and the equipment cost high. The catalyst provided by the present invention reduces the reaction temperature of ethanol steam reforming hydrogen production, reduces the reaction temperature to 500°C or below, and the hydrogen yield is the same as the yield obtained under the above-mentioned high-temperature conditions, and also reduces the demand for the temperature resistance of the reactor material, thereby significantly reducing the difficulty and cost of ethanol steam reforming hydrogen production.

[0064] Example

[0065] The present invention is described in detail below through specific examples. The experimental methods described below, unless otherwise specified, are all routine laboratory methods. The experimental materials described below, unless otherwise specified, can all be obtained from commercial channels.

[0066] Embodiment 1:

[0067] According to the total active metal loading of 10wt%, 74.08g of cobalt nitrate and 135g of white corundum are weighed, and the catalyst is prepared by an equal volume impregnation method; the solid phase (the carrier loaded with active metal salts) is dried in an oven at 105°C for 5h, then taken out and placed in a tubular furnace, and the temperature is increased from room temperature to 300°C at 3°C / min for 90min in an air atmosphere of 80mL / min, and then the temperature is increased at 20°C / min for 25min to 800°C, and calcined at 800°C for 6h; the calcined solid is loaded into an ethanol reforming hydrogen production reactor, and a 25wt% ethanol solution is introduced at 450°C at 0.05mL / min for in-situ reduction for 60min to obtain 150g of a non-precious metal catalyst.

[0068] Embodiment 2:

[0069] According to the total active metal loading of 15wt%, 74.08g of cobalt nitrate and 46.48g of cerium nitrate, 85g of white corundum and 85g of olivine were weighed, and the catalyst was prepared by an equal volume impregnation method; the solid phase was dried in an oven at 90°C for 3h, then taken out and placed in a tubular furnace, and the temperature was increased from room temperature to 500°C at 10°C / min for 47min in an air atmosphere of 120mL / min, and then heated to 850°C at 50°C / min for 7min, and calcined at 850°C for 6h; the calcined solid was loaded into an ethanol reforming hydrogen production reactor, and a 20wt% ethanol solution was introduced at 450°C at 0.04mL / min for in-situ reduction for 30min to obtain 200g of a non-precious metal catalyst.

[0070] Embodiment 3:

[0071] According to the total active metal loading of 10wt%, 30.37g of nickel chloride and 37.04g of cobalt nitrate, 100g of white corundum and 35g of cerium oxide were weighed, and the catalyst was prepared by an equal volume impregnation method; the solid phase was dried in an oven at 90°C for 6h, then taken out and placed in a tubular furnace, and the temperature was increased from room temperature to 450°C at 5°C / min for 84min in an air atmosphere of 100mL / min, and then heated to 850°C at 20°C / min for 20min, and calcined at 850°C for 4h; the calcined solid was loaded into an ethanol reforming hydrogen production reactor, and a 15wt% ethanol solution was introduced at 500°C at 0.07mL / min for in-situ reduction for 100min to obtain 150g of a non-precious metal catalyst.

[0072] Embodiment 4:

[0073] According to the total active metal loading of 12wt%, 74.08g of cobalt nitrate and 9.30g of cerium nitrate, and 132g of white corundum are weighed, and the catalyst is prepared by an equal volume impregnation method; the solid phase is dried in an oven at 100°C for 4h, then taken out and placed in a tubular furnace, and the temperature is increased from room temperature to 500°C at 5°C / min for 96min in an air atmosphere of 100mL / min, and then heated to 800°C at 10°C / min for 30min, and calcined at 800°C for 8h; the calcined solid is loaded into an ethanol reforming hydrogen production reactor, and a 25wt% methanol solution is introduced at 300°C at 0.2mL / min for in-situ reduction for 80min to obtain 150g of a non-precious metal catalyst.

[0074] Comparative Example 1:

[0075] According to the total active metal loading of 10wt%, 36.07g of iron nitrate and 19.68g of copper nitrate, and 90g of white corundum are weighed, and the catalyst is prepared by an equal volume impregnation method; the solid phase is dried in an oven at 85°C for 6h, then taken out and placed in a tubular furnace, and the temperature is increased from room temperature to 450°C at 5°C / min for 84min in an air atmosphere of 100mL / min, and then heated to 750°C at 30°C / min for 10min, and calcined at 750°C for 6h; the calcined solid is loaded into an ethanol reforming hydrogen production reactor, and a 25wt% ethanol solution is introduced at 500°C at 0.05mL / min for in-situ reduction for 80min to obtain 100g of a non-precious metal catalyst.

[0076] Comparative Example 2:

[0077] According to the total active metal loading of 10wt%, 49.39g of cobalt nitrate and 19.68g of copper nitrate, and 90g of white corundum are weighed, and the catalyst is prepared by an equal volume impregnation method; the solid phase is dried in an oven at 95°C for 8h, then taken out and placed in a tubular furnace, and the temperature is increased from room temperature to 500°C at 5°C / min for 96min in an air atmosphere of 120mL / min, and then heated to 70°C at 20°C / min for 10min, and calcined at 700°C for 7h; the calcined solid is loaded into an ethanol reforming hydrogen production reactor, and a 25wt% methanol solution is introduced at 500°C at 0.2mL / min for in-situ reduction for 60min to obtain 100g of a non-precious metal catalyst.

[0078] Example 5: Testing the performance of non-precious metal catalysts for ethanol steam reforming to produce hydrogen

[0079] The catalyst samples obtained in Examples 1 to 3 and Comparative Example 1 were reduced under the same conditions for 1 hour in a fixed bed reactor (a tubular fixed bed reactor with a length of 1 m and an inner diameter of 5 cm) at 500°C, and then an ethanol-water solution with an equal composition and flow rate was introduced; the catalyst samples obtained in Example 4 and Comparative Example 2 were reduced under the same conditions for 1 hour in a fixed bed reactor (a tubular fixed bed reactor with a length of 1 m and an inner diameter of 5 cm) at 300°C, and then an methanol-water solution with an equal composition and flow rate was introduced to analyze the product gas composition with a gas chromatograph (BFRL-3420A) and calculate the hydrogen yield. The test results are shown in Table 1.

[0080] Table 1 Comparison of catalyst performance obtained in Examples 1 to 4 and Comparative Examples 1 to 2

[0081] catalyst Hydrogen yield / % Duration / h Example 1 94 >2500 Example 2 90 >30 Example 3 88 >30 Comparative Example 1 72 <10 Example 4 97 >2500 Comparative Example 2 58 <10

[0082] As attached Figure 1 As shown, the hydrogen yield of the catalyst prepared in the above Example 1 was stable at more than 90% within 2000 hours, and no obvious deactivation was observed.

[0083] like Figure 2 As shown, after the catalyst prepared in the above Example 1 has been running for 2000 hours, the active metal crystals of the catalyst are still relatively evenly attached to the surface of the carrier, and no obvious carbon deposition is observed under high resolution.

[0084] like Figure 3 As shown, the catalyst was subjected to thermogravimetric analysis in air atmosphere after 2000 hours, and the mass increased by about 4% at about 300-400°C, indicating that carbon deposits were very little or non-existent, and the increase in catalyst mass could be attributed to the secondary oxidation of the catalyst.

[0085] From the above examples, it can be seen that the temperature of the present invention for ethanol steam reforming hydrogen production is lower than 500°C, which is significantly lower than the temperature used by the catalyst in the prior art; the catalyst prepared by the present invention can be heated to 200-4000h. -1 The catalyst can be operated at a gas hourly space velocity (GHSV) of 400 to 800°C to obtain improved catalyst performance. The catalyst can be operated in a large temperature window of 400 to 800°C, thereby achieving efficient reforming of ethanol and first- and second-generation bioethanol to produce hydrogen. The catalyst can be effectively used at lower temperatures (below 500°C) and exhibits very little carbon deposition (see Figure 2 , Figure 3 ).

[0086] It should be noted that the embodiments described above are only preferred embodiments of the present invention, which are used for illustration to facilitate understanding of the present invention and do not constitute any limitation to the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein. On the contrary, the present invention can be extended to all other methods and applications with the same functions.

Claims

1. A non-precious metal catalyst for low-temperature steam reforming of small molecule alcohols to produce hydrogen, which is composed of a carrier and an active metal supported on the carrier; wherein: The active metal includes a non-noble metal and / or a rare earth metal. The non-noble metal includes cobalt and / or nickel. The rare earth metal includes lanthanum and / or cerium.

2. The non-precious metal catalyst according to claim 1, characterized in that The material of the carrier includes one or more of olivine, white corundum, magnesium oxide, lanthanum oxide, and cerium oxide; preferably, the loading amount of the active metal is 1wt% to 30wt%.

3. The non-precious metal catalyst according to claim 1 or 2, characterized in that When the active metal comprises a non-noble metal and a rare earth metal, the molar ratio of the non-noble metal to the rare earth metal in the catalyst is ≥1.0, preferably ≥1.

5.

4. A method for preparing a non-precious metal catalyst for steam reforming of small molecule alcohols to produce hydrogen, comprising: Step A, impregnating the carrier with an active metal salt aqueous solution, and then drying and calcining the carrier loaded with the active metal salt in sequence to obtain a carrier loaded with an active metal oxide; Step B, in situ reducing the carrier loaded with active metal oxide in a reaction environment for small molecule alcohol reforming to produce hydrogen, to obtain a non-precious metal catalyst for small molecule alcohol steam reforming to produce hydrogen.

5. The preparation method according to claim 4, characterized in that: The active metal salt aqueous solution comprises one or more of cobalt, nickel, lanthanum and cerium salt aqueous solutions; and / or, the material of the carrier comprises one or more of olivine, white corundum, magnesium oxide, lanthanum oxide and cerium oxide.

6. The preparation method according to claim 4, characterized in that: In the carrier loaded with active metal oxide, the loading amount of active metal oxide is 1wt% to 30wt%, and the mass fraction of the carrier is 70wt% to 99wt%.

7. The preparation method according to any one of claims 4 to 6, characterized in that: In step A, the drying temperature is 60 to 200° C.; and / or the drying time is 1 to 8 hours.

8. The preparation method according to any one of claims 4 to 7, characterized in that: In step A, the calcination is performed three times; wherein the first calcination is a temperature-raising calcination, the temperature of the first calcination is 100-500°C, the time of the first calcination is 20-60min, and the heating rate of the first calcination is 3-10°C / min; the second calcination is a temperature-raising calcination, the temperature of the second calcination is 500-800°C, the time of the second calcination is 10-30min, and the heating rate of the second calcination is 20°C / min; the third calcination is a constant temperature calcination, the temperature of the third calcination is 750-1000°C, and the time of the second calcination is 1-6h.

9. The preparation method according to any one of claims 4 to 8, characterized in that: In step B, the small molecule alcohol steam reforming hydrogen production reaction environment is composed of a small molecule alcohol solution with a concentration of 1wt% to 50wt% at a flow rate of 0.001 to 0.1 mL / min; preferably, the temperature of the in-situ reduction is 300 to 800°C, and the time of the in-situ reduction is 20 to 100 min.

10. Use of the non-precious metal catalyst according to any one of claims 1 to 3 or the non-precious metal catalyst prepared by the preparation method according to any one of claims 4 to 9 in hydrogen production by steam reforming of small molecule alcohols; preferably, the temperature of hydrogen production by steam reforming of small molecule alcohols is 200 to 800° C., and the gas hourly space velocity (GHSV) is 4000 to 20000 h -1 .

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