An apparatus and method for hydrogen production by oxidative reforming of ethanol

Abstract

The present invention provides a device and method for hydrogen production by ethanol oxidative reforming. The device includes a starting power supply, an electrothermal device, an intelligent temperature control device, a reforming hydrogen production device, a vaporization device, a preheating device, and a gas catalytic purification device. The electrothermal device, the vaporization device, and the preheating device are all arranged between the reforming hydrogen production device and the gas catalytic purification device, and the electrothermal device, the vaporization device, and the preheating device are in contact with each other for heat exchange. The method vaporizes the liquid raw material, conducts ethanol oxidative reforming to produce hydrogen, and separates the hydrogen with a purity > 99.99% through a palladium-based hydrogen separation membrane. The device of the present invention can be applied to in-situ hydrogen production in a hydrogen refueling station or on-vehicle online hydrogen production, as well as other mobile or fixed occasions that require high-purity hydrogen.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen production from ethanol, and particularly to a device and method for hydrogen production by oxidative reforming of ethanol. Background Art

[0002] Hydrogen is an ideal energy carrier that can efficiently convert renewable and clean energies such as wind energy, water energy, solar energy, and biomass energy into electrical energy through fuel cells without emitting greenhouse gases such as CO2. However, the hydrogen produced by the current ethanol reforming reaction cannot meet the intake requirements of fuel cells, making it difficult to achieve the hydrogen energy economy in the short term.

[0003] CN205668941U discloses an ethanol reformer that uses the waste heat of an engine exhaust to produce hydrogen. This device uses the waste heat of an automobile engine to catalytically reform water-containing ethanol into hydrogen-rich gas in two stages, and then passes the hydrogen-rich gas into the automobile engine for mixing and combustion with fuel. Its device and application system use a two-stage honeycomb titanium mesh structure to generate a large catalyst contact surface area, which is beneficial to the miniaturization of the reforming hydrogen production device and makes on-vehicle online hydrogen production possible; the two-stage catalytic structure realizes the mutual synergistic effect of the catalysts, solving problems such as low ethanol conversion efficiency and low hydrogen selectivity when using a single catalyst; at low temperatures, through the mutual synergistic effect of alkaline catalysts, the problems of catalyst sintering and carbon deposition are solved, and the service life of the catalyst is improved. However, this device first sprays the ethanol aqueous solution into the evaporation chamber, and then uses the automobile exhaust to heat the ethanol aqueous solution into water-containing ethanol vapor, and the water-containing ethanol vapor reacts with the catalyst to generate hydrogen. However, the evaporation time of the ethanol aqueous solution is short, and the flow distance of the ethanol vapor in the shell side is short, and the residence time is too short, which shortens the reaction time to a certain extent and reduces the reforming rate.

[0004] CN111048809A discloses a hydrogen-oxygen fuel cell intelligent power generation system based on hydrogen production by straw ethanol fermentation reforming, including: a straw ethanol fermentation system, an ethanol reforming hydrogen production system, a hydrogen-oxygen fuel cell power generation system, and a central control system. Among them, the straw ethanol fermentation system anaerobically ferments straw to obtain ethanol, the ethanol reforming hydrogen production system uses the ethanol and steam reforming reaction to obtain hydrogen, the hydrogen-oxygen fuel cell power generation system uses the hydrogen to convert chemical energy into electrical energy, and the central control system is used for online control of the straw ethanol fermentation system, the ethanol reforming hydrogen production system, and the hydrogen-oxygen fuel cell power generation system. However, this hydrogen-oxygen fuel cell intelligent power generation system based on hydrogen production by straw ethanol fermentation reforming has a large floor area and cannot be used for on-vehicle online hydrogen production.

[0005] CN107302100A discloses a hydrogen fuel cell system based on ethanol reforming for hydrogen production and its power generation method. An ethanol reactor is adopted, and ethanol is used as the raw material for the hydrogen fuel cell. Ethanol undergoes steam reforming reaction to generate hydrogen; and through the water-gas shift in the water-gas shift reactor and the selective oxidation of carbon monoxide in the carbon monoxide selective oxidation reactor, all carbon monoxide in the by-products reacts to form carbon dioxide. The CO-free hydrogen-rich gas generated by the steam reforming reaction is used as fuel, and electrical energy is released through the electrochemical reaction for output. However, this hydrogen fuel cell system requires an external heating device to heat the ethanol steam reforming reactor to provide the heat required for the steam reforming reaction, which increases the floor area of the system to a certain extent and raises the power generation cost.

[0006] Therefore, it is of great significance to develop a device and method for ethanol oxidative reforming for hydrogen production that can obtain high-purity hydrogen and is applicable to fixed or mobile occasions. Summary of the Invention

[0007] In view of the problems existing in the prior art, the present invention provides a device and method for ethanol oxidative reforming for hydrogen production. After co-vaporizing an ethanol aqueous solution and air, a hydrogen-rich gas is generated under the action of a reforming catalyst for hydrogen production. The hydrogen-rich gas is separated by a palladium-based hydrogen separation membrane to obtain high-purity hydrogen. Among them, the gas on the retentate side that does not pass through the palladium-based hydrogen separation membrane is converted into carbon dioxide and water under the action of an oxidation catalyst. The high-purity hydrogen prepared by the device of the present invention has a purity > 99.99%, and is applicable to in-situ hydrogen production in hydrogen refueling stations and on-vehicle online hydrogen production, as well as other mobile or fixed occasions that require high-purity hydrogen.

[0008] To achieve this purpose, the present invention adopts the following technical solutions:

[0009] In the first aspect, the present invention provides a device for ethanol oxidative reforming for hydrogen production. The device includes a starting power supply, an electric heating device, an intelligent temperature control device, a reforming device for hydrogen production, a vaporization device, a preheating device, and a gas catalytic purification device; the intelligent temperature control device is connected to the starting power supply and controls the electric heating device to generate heat. The gas catalytic purification device is arranged outside the reforming device for hydrogen production. The electric heating device, the vaporization device, and the preheating device are all arranged between the reforming device for hydrogen production and the gas catalytic purification device. The electric heating device, the vaporization device, and the preheating device are in contact with each other for heat exchange. The reforming device for hydrogen production is filled with a reforming catalyst for hydrogen production and a palladium-based hydrogen separation membrane; the gas catalytic purification device is filled with an oxidation catalyst.

[0010] The device for hydrogen production by ethanol oxidative reforming according to the present invention first uses an electrothermal device to heat the entire device to the vaporization temperature, and then ethanol aqueous solution and air are introduced into the vaporization device. Ethanol, water and air are fully preheated and mixed in the vaporization device. After forming a uniform and stable reaction gas stream, it enters the reforming hydrogen production device. Under the action of the reforming hydrogen production catalyst, it is converted into hydrogen-rich gas, and high-purity hydrogen is separated in real time through the palladium-based hydrogen separation membrane in the reforming hydrogen production device; part of the hydrogen-rich gas that does not pass through the palladium-based hydrogen separation membrane becomes the gas on the retention side, and enters the gas catalytic purification device together with the air preheated by the preheating device, and is converted into carbon dioxide and water under the action of the oxidation catalyst.

[0011] The mutual positional relationship among the electrothermal device, the vaporization device and the preheating device in the device of the present invention is not limited, and they can be arranged from the inside to the outside or from the outside to the inside, or they can be an electric heating wire, a vaporization tube and a waste heat tube, and the three are wound together. As long as heat exchange among the three can be realized and it is between the reforming hydrogen production device and the gas catalytic purification device. In this way, the heat generated by the electrothermal device can be directly transferred to the vaporization device and the preheating device, and directly or indirectly transferred to the reforming hydrogen production device and the gas catalytic purification device. When ethanol, water and air are fully preheated and mixed in the vaporization device, an exothermic reaction occurs in the reforming hydrogen production reaction chamber, and this part of the heat can be transferred to the vaporization device and the preheating device; the air preheated by the preheating device and the gas on the retention side in the reforming hydrogen production device also have an exothermic reaction in the catalytic purification device, and this part of the heat can continue to be transferred to the vaporization device and the preheating device, thereby realizing that the temperatures of all components of the entire device are the same or similar, which can simplify the thermal management of the device and improve the energy efficiency.

[0012] The function of the intelligent temperature control device of the present invention is to control the electrothermal device to generate heat. When the heat generated by the reforming hydrogen production device and the gas catalytic purification device is sufficient to maintain the entire device to react at the target operating temperature, the intelligent temperature control device controls the electric heating wire to cut off the power and stop generating heat, which can effectively reduce the supply of external heat, and thus reduce the cost of hydrogen production by ethanol oxidative reforming.

[0013] Preferably, the volume ratio of the reforming hydrogen production device to the gas catalytic purification device is 1:0.2 to 1:2, for example, it can be 1:0.2, 1:0.3, 1:0.5, 1:0.8, 1:1, 1:1.5, 1:1.7 or 1:2, and preferably 1:0.5 to 1:1.

[0014] The volume ratio of the reforming hydrogen production device to the gas catalytic purification device of the present invention is 1:0.2 to 1:2. Not only can bioethanol containing a small amount of impurities such as acetic acid, fusel oil, and ethyl acetate be used as a liquid raw material for reforming hydrogen production, but also industrial ethanol with a higher ethanol purity can be used as a raw material for reforming hydrogen production, and high-purity hydrogen with a purity > 99.99% can be obtained.

[0015] Preferably, the vaporization device includes an ethanol aqueous solution vaporization tube.

[0016] Preferably, the preheating device includes an air preheating tube.

[0017] Preferably, the electric heating device includes an electric heating wire.

[0018] Preferably, the ethanol aqueous solution vaporization tube, the air preheating tube and the electric heating wire are wound together and arranged between the reforming hydrogen production device and the gas catalytic purification device for heat exchange.

[0019] Preferably, the palladium-based hydrogen separation membrane is columnar and includes a palladium-ruthenium-silver alloy thin film and a columnar support skeleton.

[0020] Preferably, the thickness of the palladium-ruthenium-silver alloy thin film is 3 to 5 mm, for example, it can be 3 mm, 3.2 mm, 3.5 mm, 4 mm, 4.5 mm, 4.8 mm or 5 mm.

[0021] Preferably, the diameter of the palladium-based hydrogen separation membrane is 3 to 6.35 mm, for example, it can be 3 mm, 3.3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 6 mm or 6.35 mm.

[0022] On the side of the palladium-based hydrogen separation membrane of the present invention away from the reforming hydrogen production catalyst, a gas discharge pipe is provided, and on the opposite side of the gas discharge pipe, the reforming hydrogen production device is provided with a mixed gas raw material pipe.

[0023] Preferably, the distance between the outer wall of the palladium-based hydrogen separation membrane and the inner wall of the reforming hydrogen production device is 1 to 15 mm, for example, it can be 1 mm, 2 mm, 3 mm, 5 mm, 6 mm, 8 mm, 10 mm, 13 mm or 15 mm, preferably 2 to 6 mm.

[0024] The distance between the outer wall of the palladium-based hydrogen separation membrane of the present invention and the inner wall of the reforming hydrogen production device is 1 to 15 mm. Filling the ethanol reforming hydrogen production catalyst between the outer wall of the palladium-based hydrogen separation membrane and the inner wall of the reforming hydrogen production device has the advantage of intensive use of space.

[0025] Preferably, the device includes a liquid sampling device and an air sampling device connected to the vaporization device.

[0026] The liquid sampling device in the device of the present invention is connected to an ethanol aqueous solution storage tank.

[0027] Preferably, the air sampling device is also connected to the preheating device.

[0028] Preferably, an air filtering device is provided in the air sampling device.

[0029] Preferably, an air filtration device is provided in the air sampling device of the present invention, which is mainly used to remove large particles in the first air and the second air to ensure that the particle size of the particles in the first air and the second air is < 10 μm.

[0030] Preferably, the device includes a heat preservation sleeve arranged outside the gas catalytic purification device.

[0031] In a second aspect, the present invention provides a method for hydrogen production by ethanol oxidative reforming, and the method is carried out by using the device for hydrogen production by ethanol oxidative reforming described in the first aspect.

[0032] The method for hydrogen production by ethanol oxidative reforming of the present invention successfully couples ethanol reforming for hydrogen production and a palladium-based hydrogen separation membrane to obtain high-purity hydrogen at a suitable target operating temperature, and catalytically purifies the gas on the retentate side that has not passed through the palladium-based hydrogen separation membrane to prevent air pollution caused by CH4 and CO and the explosion caused by residual hydrogen; moreover, the heat in the processes of ethanol reforming for hydrogen production and gas catalytic purification is fully utilized to reduce heat waste.

[0033] Preferably, the method includes the following steps:

[0034] (1) The intelligent temperature control device connected to the starting power supply controls the heating device to generate heat. After heating the device for hydrogen production by ethanol oxidative reforming to the vaporization temperature, the aqueous ethanol solution and the first air enter the vaporization device and are vaporized to obtain a mixed gas raw material.

[0035] (2) The reforming hydrogen production device is continuously heated to the target operating temperature, and the mixed gas raw material described in step (1) enters the reforming hydrogen production device and generates a first gas under the action of a reforming hydrogen production catalyst. The first gas passes through the palladium-based hydrogen separation membrane to form a second gas.

[0036] (3) The part of the first gas that has not passed through the palladium-based hydrogen separation membrane forms a retentate side gas, which enters the gas catalytic purification device together with the second air preheated by the preheating device and is converted into carbon dioxide and water under the action of an oxidation-type catalyst.

[0037] The device for hydrogen production by ethanol oxidative reforming of the present invention cannot be dry-burned. After reaching the vaporization temperature, sampling is carried out immediately, and then it is continuously heated to the target operating temperature.

[0038] The method for hydrogen production by ethanol oxidative reforming of the present invention preferably uses an aqueous solution of bioethanol for vaporization hydrogen production, because bioethanol is ethanol obtained by converting various biomasses through the fermentation of microorganisms, which is a renewable resource and does not emit additional CO2 into the carbon cycle of nature during production and use.

[0039] Preferably, the vaporization temperature in step (1) is 150 - 250°C, for example, it can be 150°C, 160°C, 180°C, 200°C, 230°C or 250°C, and preferably it is 180 - 200°C.

[0040] Preferably, the molar ratio of ethanol to water in the aqueous ethanol solution is 1:1 - 1:10, for example, it can be 1:1, 1:1.5, 1:2, 1:3, 1:5, 1:8, 1:9, 1:9.5, 1:9.8 or 1:10, and preferably it is 1:2 - 1:3.

[0041] Preferably, the particle size of the particulate matter in the first air is < 10 μm, for example, it can be 9.5 μm, 8 μm, 7 μm, 6 μm, 5 μm, 4 μm, 3 μm or 1 μm.

[0042] Preferably, the molar ratio of ethanol in the aqueous ethanol solution to oxygen in the first air is 1:0.2 - 1:0.8, for example, it can be 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7 or 1:0.8, and preferably it is 1:0.5 - 1:0.7.

[0043] In the present invention, the molar ratio of ethanol in the aqueous ethanol solution to oxygen in the first air is 1:0.2 - 1:0.8, making the ethanol oxidative reforming for hydrogen production reaction an exothermic reaction, reducing the heat supply of the electrothermal device, greatly saving the hydrogen production cost, and high-purity hydrogen can be obtained.

[0044] Preferably, the target operating temperature in step (2) is 380 - 500°C, for example, it can be 380°C, 400°C, 420°C, 450°C, 480°C or 500°C, and preferably it is 430 - 480°C.

[0045] In the present invention, preferably, the target operating temperature in step (2) is 380 - 500°C. Within this temperature range, the reaction rate of ethanol, water and oxygen in the air under the action of the reforming hydrogen production catalyst is fast, the reaction is sufficient, and the concentration of the hydrogen-rich gas obtained is relatively high. Moreover, within this temperature range, the palladium-based hydrogen separation membrane can obtain a good hydrogen separation effect, and hydrogen with a purity > 99.99% can be obtained.

[0046] Preferably, the molar flow rate of ethanol in the aqueous ethanol solution to the mass of the reforming hydrogen production catalyst is 0.8 - 5 [(mol·min -1 ) / kg -1 , for example, it can be 0.8 [(mol·min -1 ) / kg -1 , 0.9 [(mol·min -1 ) / kg -1 , 1 [(mol·min -1) / kg -1 , 1.5 [(mol·min -1 ) / kg -1 , 2 [(mol·min -1 ) / kg -1 , 3 [(mol·min -1 ) / kg -1 , 4 [(mol·min -1 ) / kg -1 , or 5 [(mol·min -1 ) / kg -1 .

[0047] Preferably, the hydrogen concentration in the first gas is 30% - 50%, for example, it can be 30%, 32%, 35%, 40%, 45%, 48% or 50%.

[0048] Preferably, the purity of hydrogen in the second gas > 99.99%, for example, it can be 99.991%, 99.992%, 99.993%, 99.995%, 99.997% or 99.999%.

[0049] Preferably, the molar flow rate of ethanol in the aqueous ethanol solution in step (3) to the mass of the oxidation catalyst is 2 - 12 [(mol·min -1 ) / kg -1 , for example, it can be 2 [(mol·min -1 ) / kg -1 , 3 [(mol·min -1 ) / kg -1 , 5 [(mol·min -1 ) / kg -1 , 7 [(mol·min -1 ) / kg -1 , 9 [(mol·min -1 ) / kg -1 , 10 [(mol·min -1 ) / kg -1 , 11 [(mol·min -1 ) / kg -1 , or 12 [(mol·min -1 ) / kg -1 .

[0050] Preferably, the molar ratio of ethanol in the aqueous ethanol solution to oxygen in the second air is 1:1 - 1:3, for example, it can be 1:1, 1:1.2, 1:1.5, 1:2, 1:2.5, 1:2.8 or 1:3.

[0051] Preferably, the particle size of the particulate matter in the second air is < 10 μm, and for example, it can be 9.5 μm, 8 μm, 7 μm, 6 μm, 5 μm, 4 μm, 3 μm or 1 μm.

[0052] The numerical ranges described in the present invention not only include the point values listed above, but also include any point values between the above numerical ranges not listed. Due to space limitations and for the sake of simplicity, the specific point values included in the scope of the present invention are not exhaustively listed herein.

[0053] As a preferred technical solution of the present invention, the method includes the following steps:

[0054] (1) The intelligent temperature control device connected to the starting power supply controls the heating of the electric heating device. After heating the device for ethanol oxidative reforming to produce hydrogen to the vaporization temperature of 150 - 250 °C, an ethanol aqueous solution and the first air with a particulate matter particle size < 10 μm enter the vaporization device, and a mixed gas raw material is obtained through vaporization; the molar ratio of ethanol to water in the ethanol aqueous solution is 1:1 - 1:10; the molar ratio of ethanol in the ethanol aqueous solution to oxygen in the first air is 1:0.2 - 1:0.8;

[0055] (2) The reforming hydrogen production device is continuously heated to the target operating temperature of 380 - 500 °C. The mixed gas raw material in step (1) enters the reforming hydrogen production device, and under the action of the reforming hydrogen production catalyst, a first gas with a hydrogen concentration of 30% - 50% is generated. The first gas passes through the palladium-based hydrogen separation membrane to form a second gas with a hydrogen purity > 99.99%; the molar flow rate of ethanol in the ethanol aqueous solution to the mass of the reforming hydrogen production catalyst is 0.8 - 5 [(mol·min -1 ) / kg -1 ;

[0056] (3) The part of the first gas that does not pass through the palladium-based hydrogen separation membrane forms a retentate-side gas, which enters the gas catalytic purification device together with the second air with a particulate matter particle size < 10 μm preheated by the preheating device, and is converted into carbon dioxide and water under the action of the oxidation-type catalyst; the molar flow rate of ethanol in the ethanol aqueous solution to the mass of the oxidation-type catalyst is 2 - 12 [(mol·min -1 ) / kg -1 , and the molar ratio of ethanol in the ethanol aqueous solution to oxygen in the second air is 1:1 - 1:3.

[0057] In a third aspect, the present invention provides a use of the device for ethanol oxidative reforming to produce hydrogen according to the first aspect, and the device is used to produce hydrogen with a purity > 99.99%.

[0058] Preferably, the device is used for in-situ hydrogen production in a hydrogen refueling station or on-vehicle online hydrogen production.

[0059] The device of the present invention can be used in various mobile or fixed occasions that require high-purity hydrogen, and is preferably used for in-situ hydrogen production in hydrogen refueling stations or on-vehicle online hydrogen production.

[0060] Compared with the prior art, the present invention has at least the following beneficial effects:

[0061] (1) The device for hydrogen production by ethanol oxidative reforming provided by the present invention combines functions such as vaporization of liquid raw materials, ethanol oxidative reforming for hydrogen production, separation of high-purity hydrogen, catalytic purification of retained gas, and heat recovery and utilization, and can be used in various mobile or fixed occasions that require high-purity hydrogen;

[0062] (2) The method for hydrogen production by ethanol oxidative reforming provided by the present invention can produce hydrogen with a purity > 99.99%, which belongs to a green hydrogen production process, has good economic and environmental benefits, and is suitable for large-scale popularization and application. Description of the Drawings

[0063] Figure 1 is a schematic diagram of the device for hydrogen production by ethanol oxidative reforming provided in Embodiment 1 of the present invention.

[0064] Figure 2 is a sectional view of the device for hydrogen production by ethanol oxidative reforming provided in Embodiment 1 of the present invention.

[0065] In the figure: 1 - reforming hydrogen production device; 2 - ethanol aqueous solution vaporization tube; 3 - gas catalytic purification device; 4 - palladium-based hydrogen separation membrane; 5 - gas discharge tube; 6 - mixed gas raw material tube. Detailed Embodiments

[0066] The technical solutions of the present invention will be further described below in conjunction with the drawings and through specific embodiments.

[0067] The present invention will be further described in detail below. However, the following examples are only simple examples of the present invention and do not represent or limit the scope of the protection of the present invention. The scope of protection of the present invention is subject to the claims.

[0068] It should be understood that in the description of the present invention, the orientation or positional relationship indicated by terms such as "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, so it cannot be understood as a limitation to the present invention. In addition, terms such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise stated, the meaning of "plurality" is two or more.

[0069] It should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "set", "connected", "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific situations.

[0070] Those skilled in the art should understand that the present invention necessarily includes necessary pipelines, conventional valves and general pump equipment for realizing the complete process, but the above contents do not belong to the main inventive points of the present invention. Those skilled in the art can add and arrange them by themselves based on the process flow and equipment structure selection, and the present invention has no special requirements and specific limitations on this.

[0071] Example 1

[0072] This embodiment provides a device for hydrogen production by ethanol oxidative reforming. The schematic diagram of the device is as Figure 1 shown, and the sectional view of the device is as Figure 2 shown.

[0073] The device includes a starting power supply, an electric heating wire, an intelligent temperature control device, a reforming hydrogen production device 1, an ethanol aqueous solution vaporization tube 2, an air preheating tube, and a gas catalytic purification device 3; the intelligent temperature control device is connected to the starting power supply and controls the electric heating device to generate heat. The gas catalytic purification device 3 is arranged outside the reforming hydrogen production device 1, and the ethanol aqueous solution vaporization tube 2, the air preheating tube, and the electric heating wire are wound together and arranged between the reforming hydrogen production device 1 and the gas catalytic purification device 3 for heat exchange.

[0074] The ethanol aqueous solution vaporization tube 2 is a stainless steel tube with an outer diameter of 4 mm. The reforming hydrogen production device 1 has an inner diameter of 25 mm and contains a reforming hydrogen production catalyst with a bed height of 40 mm and a palladium-based hydrogen separation membrane 4 with a diameter of 5 mm and a length of 80 mm. The palladium-based hydrogen separation membrane 4 comprises a palladium-ruthenium-silver alloy thin film with a thickness of 3 mm and a columnar support skeleton; the distance between the outer wall of the palladium-based hydrogen separation membrane 4 and the inner wall of the reforming hydrogen production device 3 is 10 mm.

[0075] The gas catalytic purification device 3 is a concentric cylinder with an inner diameter of 30 mm and an outer diameter of 50 mm, which is filled with an oxidation catalyst with a catalyst bed height of 100 mm and contains quartz sand with a volume fraction of 30%. The volume ratio of the reforming hydrogen production device 1 to the gas catalytic purification device 3 is 1:2. Two gas discharge pipes 5 are arranged on one side of the palladium-based hydrogen separation membrane 4 away from the reforming hydrogen production catalyst, and a mixed gas raw material pipe 6 is arranged on the opposite side of the reforming hydrogen production device to the gas discharge pipe 5.

[0076] The device includes a liquid sampling device and an air sampling device connected to the vaporization device; the air sampling device is also connected to a preheating device; an air filtering device is arranged in the air sampling device; the device includes a heat preservation sleeve arranged outside the gas catalytic purification device.

[0077] Example 2

[0078] This example provides a device for ethanol oxidative reforming to produce hydrogen, which includes a starting power supply, an electric heating wire, an intelligent temperature control device, a reforming hydrogen production device, an ethanol aqueous solution vaporization tube, an air preheating tube and a gas catalytic purification device; the intelligent temperature control device is connected to the starting power supply and controls the electric heating device to generate heat. The gas catalytic purification device is arranged outside the reforming hydrogen production device. The ethanol aqueous solution vaporization tube, the air preheating tube and the electric heating wire are wound together and arranged between the reforming hydrogen production device and the gas catalytic purification device for heat exchange.

[0079] The ethanol aqueous solution vaporization tube is a stainless steel tube with an outer diameter of 4 mm. The reforming hydrogen production device has an inner diameter of 5 mm and contains a reforming hydrogen production catalyst with a bed height of 40 mm and a palladium-based hydrogen separation membrane with a diameter of 3 mm and a length of 80 mm. The palladium-based hydrogen separation membrane comprises a palladium-ruthenium-silver alloy thin film with a thickness of 4 mm and a columnar support skeleton; the distance between the outer wall of the palladium-based hydrogen separation membrane and the inner wall of the reforming hydrogen production device is 1 mm.

[0080] The gas catalytic purification device is a concentric cylinder with an inner diameter of 30 mm and an outer diameter of 50 mm, which is filled with an oxidation catalyst with a catalyst bed height of 100 mm and contains quartz sand with a volume fraction of 30%. The volume ratio of the reforming hydrogen production device to the gas catalytic purification device is 1:0.2.

[0081] The device includes a liquid sampling device and an air sampling device connected to a vaporization device; the air sampling device is also connected to a preheating device; an air filtration device is provided inside the air sampling device; the device includes a heat-insulating jacket arranged outside the gas catalytic purification device.

[0082] Example 3

[0083] This example provides a device for hydrogen production by ethanol oxidative reforming. The device includes a starting power supply, a heating wire, an intelligent temperature control device, a reforming hydrogen production device, an ethanol aqueous solution vaporization tube, an air preheating tube, and a gas catalytic purification device; the intelligent temperature control device is connected to the starting power supply and controls the heating of the heating device. The gas catalytic purification device is arranged outside the reforming hydrogen production device. The ethanol aqueous solution vaporization tube, the air preheating tube, and the heating wire are wound together and arranged between the reforming hydrogen production device and the gas catalytic purification device for heat exchange.

[0084] The ethanol aqueous solution vaporization tube is a stainless steel tube with an outer diameter of 4 mm. The inner diameter of the reforming hydrogen production device is 36.35 mm, which contains a reforming hydrogen production catalyst with a bed height of 40 mm and a palladium-based hydrogen separation membrane with a diameter of 6.35 mm and a length of 80 mm. The palladium-based hydrogen separation membrane includes a palladium-ruthenium-silver alloy thin film with a thickness of 5 mm and a columnar support skeleton; the distance between the outer wall of the palladium-based hydrogen separation membrane and the inner wall of the reforming hydrogen production device is 15 mm.

[0085] The gas catalytic purification device is a concentric cylinder with an inner diameter of 30 mm and an outer diameter of 50 mm, which contains an oxidation catalyst with a catalyst bed height of 100 mm and includes 30% by volume of quartz sand. The volume ratio of the reforming hydrogen production device to the gas catalytic purification device is 1:0.8.

[0086] The device includes a liquid sampling device and an air sampling device connected to a vaporization device; the air sampling device is also connected to a preheating device; an air filtration device is provided inside the air sampling device; the device includes a heat-insulating jacket arranged outside the gas catalytic purification device.

[0087] Comparative Example 1

[0088] This comparative example provides a device for hydrogen production by ethanol oxidative reforming. Except that no palladium-based hydrogen separation membrane is provided inside the reforming hydrogen production device, the rest are the same as in Example 1.

[0089] Application Example 1

[0090] This application example provides a method for hydrogen production by ethanol oxidative reforming. The method is carried out using the device provided in Example 1. The method includes the following steps:

[0091] (1) The intelligent temperature control device connected to the starting power supply controls the heating of the electric heating device. After heating the ethanol oxidative reforming hydrogen production device to the vaporization temperature of 200 °C, the ethanol aqueous solution and the first air with a particulate matter diameter of 9 μm enter the vaporization device and are vaporized to obtain a mixed gas raw material; the molar ratio of ethanol to water in the ethanol aqueous solution is 1:8; the molar ratio of ethanol in the ethanol aqueous solution to oxygen in the first air is 1:0.6;

[0092] (2) The reforming hydrogen production device is continuously heated to the target operating temperature of 400 °C. The mixed gas raw material described in step (1) enters the reforming hydrogen production device and, under the action of the reforming hydrogen production catalyst 1% Rh / Ce 0.7 La 0.3 O 2-δ / Al2O3, produces a first gas with a hydrogen concentration of 29%. The first gas passes through the palladium-based hydrogen separation membrane to form a second gas; the molar flow rate of ethanol in the ethanol aqueous solution is 3 [(mol·min -1 ) / kg -1 ;

[0093] (3) The part of the first gas that does not pass through the palladium-based hydrogen separation membrane forms a retentate side gas, which enters the gas catalytic purification device together with the second air with a particulate matter diameter of 7 μm preheated by the preheating device. Under the action of the oxidation catalyst 1% Pt / Ce 0.7 La 0.3 O 2-δ / Al2O3 - 2% MgO, it is converted into carbon dioxide and water; the molar flow rate of ethanol in the ethanol aqueous solution is 9 [(mol·min -1 ) / kg -1 , and the molar ratio of ethanol in the ethanol aqueous solution to oxygen in the second air is 1:2.

[0094] Application Example 2

[0095] This application example provides a method for ethanol oxidative reforming hydrogen production, and the method is carried out using the device provided in Example 2. The method includes the following steps:

[0096] (1) The intelligent temperature control device connected to the starting power supply controls the heating of the electric heating device. After heating the ethanol oxidative reforming hydrogen production device to the vaporization temperature of 250 °C, the ethanol aqueous solution and the first air with a particulate matter diameter of 4 μm enter the vaporization device and are vaporized to obtain a mixed gas raw material; the molar ratio of ethanol to water in the ethanol aqueous solution is 1:10; the molar ratio of ethanol in the ethanol aqueous solution to oxygen in the first air is 1:0.8;

[0097] (2) The reforming hydrogen production device is continuously heated to the target operating temperature of 380 °C. The mixed gas raw material described in step (1) enters the reforming hydrogen production device and, under the action of the reforming hydrogen production catalyst 1% Rh / Ce 0.7 La 0.3 O 2-δ / Al2O3, produces a first gas with a hydrogen concentration of 50%. The first gas permeates through the palladium-based hydrogen separation membrane to form a second gas; the molar flow rate of ethanol in the aqueous ethanol solution to the mass of the reforming hydrogen production catalyst is 5 [(mol·min -1 ) / kg -1 ;

[0098] (3) The part of the first gas that does not permeate through the palladium-based hydrogen separation membrane forms a retentate-side gas, which enters the gas catalytic purification device together with the second air with a particle size of 5 μm of particulate matter preheated by the preheating device. Under the action of the oxidation catalyst 1% Pt / Ce 0.7 La 0.3 O 2-δ / Al2O3 - 2% MgO, it is converted into carbon dioxide and water; the molar flow rate of ethanol in the aqueous ethanol solution to the mass of the oxidation catalyst is 2 [(mol·min -1 ) / kg -1 , and the molar ratio of ethanol in the aqueous ethanol solution to oxygen in the second air is 1:1.

[0099] Application Example 3

[0100] This application example provides a method for ethanol oxidative reforming to produce hydrogen, and the method is carried out using the device provided in Example 3. The method includes the following steps:

[0101] (1) The intelligent temperature control device connected to the startup power supply controls the heating of the electric heating device. After heating the ethanol oxidative reforming to hydrogen production device to the vaporization temperature of 150 °C, the aqueous ethanol solution and the first air with a particle size of 7 μm of particulate matter enter the vaporization device and are vaporized to obtain a mixed gas raw material; the molar ratio of ethanol to water in the aqueous ethanol solution is 1:1; the molar ratio of ethanol in the aqueous ethanol solution to oxygen in the first air is 1:0.2;

[0102] (2) The reforming hydrogen production device is continuously heated to the target operating temperature of 500 °C. The mixed gas raw material described in step (1) enters the reforming hydrogen production device and, under the action of the reforming hydrogen production catalyst 1% Rh / Ce 0.7 La 0.3 O 2-δ / Al2O3, produces a first gas with a hydrogen concentration of 30%. The first gas permeates through the palladium-based hydrogen separation membrane to form a second gas; the molar flow rate of ethanol in the aqueous ethanol solution to the mass of the reforming hydrogen production catalyst is 0.8 [(mol·min-1 ) / kg -1 ;

[0103] (3) The part of the first gas that does not permeate through the palladium-based hydrogen separation membrane forms the retentate-side gas, which enters the gas catalytic purification device together with the second air with a particulate matter size of 7.5 μm that has been preheated by the preheating device. Under the action of the oxidation catalyst 1% Pt / Ce 0.7 La 0.3 O 2-δ / Al2O3 - 2% MgO, it is converted into carbon dioxide and water; the molar flow rate of ethanol in the aqueous ethanol solution to the mass of the oxidation catalyst is 12 [(mol·min -1 ) / kg -1 )], and the molar ratio of ethanol in the aqueous ethanol solution to oxygen in the second air is 1:3.

[0104] Application Example 4

[0105] This application example provides a method for hydrogen production by ethanol oxidative reforming. The method is carried out using the device provided in Example 1. Except that the molar ratio of ethanol in the aqueous ethanol solution in step (1) to oxygen in the first air is replaced from 1:0.6 to 1:0.1, the rest are the same as those in Application Example 1.

[0106] Application Example 5

[0107] This application example provides a method for hydrogen production by ethanol oxidative reforming. The method is carried out using the device provided in Example 1. Except that the molar ratio of ethanol in the aqueous ethanol solution in step (1) to oxygen in the first air is replaced from 1:0.6 to 1:1, the rest are the same as those in Application Example 1.

[0108] Application Example 6

[0109] This application example provides a method for hydrogen production by ethanol oxidative reforming. The method is carried out using the device provided in Example 1. Except that the target operating temperature in step (2) of 400 °C is replaced by 350 °C, the rest are the same as those in Application Example 1.

[0110] Application Example 7

[0111] This application example provides a method for hydrogen production by ethanol oxidative reforming. The method is carried out using the device provided in Example 1. Except that the target operating temperature in step (2) of 400 °C is replaced by 550 °C, the rest are the same as those in Application Example 1.

[0112] Application Comparative Example 1

[0113] The comparative example of this application provides a method for hydrogen production by ethanol oxidative reforming. The method is carried out using the device provided in Comparative Example 1, and the method is the same as that in Application Example 1.

[0114] In the comparative example of this application, since a palladium-based hydrogen separation membrane is not provided in the reforming hydrogen production device, only hydrogen-rich gas is obtained, not pure hydrogen, which contains CH4 and CO, and the hydrogen concentration is only 30% - 50%.

[0115] The gas chromatography quantitative analysis method was used to measure the hydrogen purity in the second gas obtained in the above application examples, and the results are shown in Table 1.

[0116] Table 1

[0117]

[0118]

[0119] It can be seen from Table 1 as follows:

[0120] (1) From Application Examples 1 - 7, it can be seen that the hydrogen purity obtained by the method for hydrogen production by ethanol oxidative reforming provided by the present invention can reach more than 99.99%;

[0121] (2) From Application Example 1 and Application Examples 4 - 5, it can be seen that in Application Example 1, the molar ratio of ethanol in the aqueous ethanol solution to oxygen in the first air in step (1) is 1:0.6. Compared with the molar ratios of ethanol in the aqueous ethanol solution to oxygen in the first air in steps (1) of Application Examples 4 - 5, which are 1:0.1 and 1:1 respectively, the hydrogen purity obtained in Application Example 1 is 99.999%, while the hydrogen purities obtained in Application Examples 4 - 5 are slightly lower than that in Application Example 1, being 99.995%; thus, it shows that by limiting the molar ratio of ethanol in the aqueous ethanol solution to oxygen in the first air in step (1) within a specific range, high-purity hydrogen with a hydrogen purity of 99.999% can be obtained;

[0122] (3) From Application Example 1 and Application Examples 6 - 7, it can be seen that in Application Example 1, the target operating temperature in step (2) is 400°C. Compared with the target operating temperatures in steps (2) of Application Examples 6 - 7, which are 350°C and 550°C respectively, the hydrogen purity obtained in Application Example 1 is 99.999%, while the hydrogen purities obtained in Application Examples 6 - 7 are slightly lower than that in Application Example 1, being 99.995%; thus, it shows that by limiting the target operating temperature in step (2) within a specific range, the palladium-based hydrogen separation membrane can obtain a better hydrogen separation effect, and high-purity hydrogen with a hydrogen purity of 99.999% can be obtained;

[0123] (4) It can be seen from the comprehensive application example 1 and the application comparative example 1 that the application example 1 is carried out by using the device provided in the embodiment 1, in which a palladium-based hydrogen separation membrane is arranged in the reforming hydrogen production device. Compared with the application comparative example 1 that is carried out by using the device provided in the comparative example 1 and no palladium-based hydrogen separation membrane is arranged in the reforming hydrogen production device, since there is no palladium-based hydrogen separation membrane for high-purity hydrogen separation, only hydrogen-rich gas is obtained in the application comparative example 1, rather than pure hydrogen, which contains CH4 and CO, and the hydrogen concentration in the obtained gas is only 30% - 50%; thus, it is shown that the hydrogen with a purity > 99.99% can be obtained by arranging a palladium-based hydrogen separation membrane in the device for ethanol oxidative reforming hydrogen production of the present invention.

[0124] In summary, the device for ethanol oxidative reforming hydrogen production provided by the present invention has functions such as vaporization of liquid raw materials, ethanol oxidative reforming hydrogen production, high-purity hydrogen separation, catalytic purification of retained gas, and heat recovery and utilization, and can be used in various mobile or fixed occasions requiring high-purity hydrogen; the method can prepare hydrogen with a purity > 99.99%, belongs to a green hydrogen production process, has good economic and environmental benefits, and is suitable for large-scale popularization and application.

[0125] The applicant declares that the present invention uses the above embodiments to illustrate the detailed structural features of the present invention, but the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvement of the present invention, the equivalent replacement of the components selected by the present invention, the addition of auxiliary components, and the selection of specific methods, etc., all fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A method for hydrogen production by oxidative reforming of ethanol, characterized in that, The method includes the following steps: (1) The intelligent temperature control device connected to the starting power supply controls the heating of the electric heating device. After heating the device for ethanol oxidative reforming to produce hydrogen to the vaporization temperature, an ethanol aqueous solution and the first air enter the vaporization device and are vaporized to obtain a mixed gas raw material; (2) The reforming device for hydrogen production is continuously heated to the target operating temperature. The mixed gas raw material described in step (1) enters the reforming device for hydrogen production and generates a first gas under the action of a reforming catalyst for hydrogen production. The first gas passes through a palladium-based hydrogen separation membrane to form a second gas; the purity of hydrogen in the second gas > 99.99%; (3) The part of the first gas that does not pass through the palladium-based hydrogen separation membrane forms a retentate side gas, which enters the gas catalytic purification device together with the second air preheated by the preheating device and is converted into carbon dioxide and water under the action of an oxidation catalyst; The method is carried out using the following device for ethanol oxidative reforming to produce hydrogen: The device for ethanol oxidative reforming to produce hydrogen includes a starting power supply, an electric heating device, an intelligent temperature control device, a reforming device for hydrogen production, a vaporization device, a preheating device, and a gas catalytic purification device; the device for ethanol oxidative reforming to produce hydrogen includes a liquid sampling device and an air sampling device connected to the vaporization device; the air sampling device is also connected to the preheating device; The intelligent temperature control device is connected to the starting power supply and controls the heating of the electric heating device. The gas catalytic purification device is arranged outside the reforming device for hydrogen production. The electric heating device, the vaporization device, and the preheating device are all arranged between the reforming device for hydrogen production and the gas catalytic purification device. The electric heating device, the vaporization device, and the preheating device are in contact with each other for heat exchange. The reforming device for hydrogen production is filled with a reforming catalyst for hydrogen production and a palladium-based hydrogen separation membrane; The vaporization device includes an ethanol aqueous solution vaporization tube; the preheating device includes an air preheating tube; the electric heating device includes an electric heating wire; the ethanol aqueous solution vaporization tube, the air preheating tube, and the electric heating wire are wound together and arranged between the reforming device for hydrogen production and the gas catalytic purification device for heat exchange; The gas catalytic purification device is filled with an oxidation catalyst; The device for ethanol oxidative reforming to produce hydrogen is used for in-situ hydrogen production in a hydrogen refueling station or on-vehicle online hydrogen production.

2. The method according to claim 1, characterized in that, The volume ratio of the reforming device for hydrogen production to the gas catalytic purification device is 1:0.2 to 1:

2.

3. The method according to claim 2, wherein 4. The method according to claim 1, wherein The volume ratio of the reforming device for hydrogen production to the gas catalytic purification device is 1:0.5 to 1:

1.

5. The method according to claim 4, characterized in that, The palladium-based hydrogen separation membrane is columnar and includes a palladium-ruthenium-silver alloy thin film and a columnar support skeleton.

6. The method according to claim 1, wherein The thickness of the palladium-ruthenium-silver alloy thin film is 3 to 5 mm.

7. The method according to claim 1, wherein The diameter of the palladium-based hydrogen separation membrane is 3 to 6.35 mm.

8. The method according to claim 7, characterized in that, The distance between the outer wall of the palladium-based hydrogen separation membrane and the inner wall of the reforming device for hydrogen production is 1 to 15 mm.

9. The method according to claim 1, characterized in that The distance between the outer wall of the palladium-based hydrogen separation membrane and the inner wall of the reforming device for hydrogen production is 2 to 6 mm.

10. The method according to claim 1, characterized in that, An air filtration device is arranged in the air sampling device.

11. The method according to claim 1, characterized in that, The device includes a heat preservation sleeve arranged outside the gas catalytic purification device.

12. The method according to claim 11, wherein The vaporization temperature described in step (1) is 150 to 250 °C. The vaporization temperature described in step (1) is 180 to 200 °C.

13. The method according to claim 1, characterized in that, The molar ratio of ethanol to water in the aqueous ethanol solution is 1:1 to 1:

10.

14. The method according to claim 13, wherein The molar ratio of ethanol to water in the aqueous ethanol solution is 1:2 to 1:

3.

15. The method according to claim 1, wherein The particle size of the particulate matter in the first air is < 10 μm.

16. The method according to claim 1, characterized in that, The molar ratio of ethanol in the aqueous ethanol solution to oxygen in the first air is 1:0.2 to 1:0.

8.

17. The method according to claim 16, wherein The molar ratio of ethanol in the aqueous ethanol solution to oxygen in the first air is 1:0.5 to 1:0.

7.

18. The method according to claim 1, wherein The target operating temperature in step (2) is 380 to 500 °C.

19. The method according to claim 18, wherein The target operating temperature in step (2) is 430 to 480 °C.

20. The method according to claim 1, characterized in that The ratio of the molar flow rate of ethanol in the ethanol aqueous solution to the mass of the reforming hydrogen production catalyst is 0.8 to 5 [(mol·min -1 ) / kg -1 ].

21. The method according to claim 1, wherein The hydrogen concentration in the first gas is 30% to 50%.

22. The method according to claim 1, wherein The molar flow rate of ethanol in the aqueous ethanol solution described in step (3) to the mass of the oxidation catalyst is 2 to 12 [(mol·min -1 ) / kg -1 .

23. The method according to claim 1, characterized in that The molar ratio of ethanol in the aqueous ethanol solution to oxygen in the second air is 1:1 to 1:

3.

24. The method according to claim 1, characterized in that The particle size of the particulate matter in the second air is < 10 μm.

25. The method according to claim 1, characterized in that, The method comprises the following steps: (1) The intelligent temperature control device connected to the starting power supply controls the heating device to generate heat. After heating the device for ethanol oxidative reforming to hydrogen production to the vaporization temperature of 150 to 250 °C, the aqueous ethanol solution and the first air with a particle size of < 10 μm of particulate matter enter the vaporization device, and a mixed gas raw material is obtained through vaporization; the molar ratio of ethanol to water in the aqueous ethanol solution is 1:1 to 1:10; the molar ratio of ethanol in the aqueous ethanol solution to oxygen in the first air is 1:0.2 to 1:0.8; (2) The reforming hydrogen production device is continuously heated to the target operating temperature of 380-500 °C. The mixed gas raw material described in step (1) enters the reforming hydrogen production device and generates a first gas with a hydrogen concentration of 30%-50% under the action of a reforming hydrogen production catalyst. The first gas passes through a palladium-based hydrogen separation membrane to form a second gas with a hydrogen purity > 99.99%. The molar flow rate of ethanol in the aqueous ethanol solution to the mass of the reforming hydrogen production catalyst is 0.8-5 [(mol·min -1 ) / kg -1 ; (3) The part of the first gas that does not permeate through the palladium-based hydrogen separation membrane forms the retentate-side gas, which enters the gas catalytic purification device together with the second air with particulate matter having a particle size < 10 μm preheated by the preheating device, and is converted into carbon dioxide and water under the action of the oxidation catalyst; the molar flow rate of ethanol in the aqueous ethanol solution to the mass of the oxidation catalyst is 2 to 12 [(mol·min -1 ) / kg -1 , and the molar ratio of ethanol in the aqueous ethanol solution to oxygen in the second air is 1:1 to 1:3.

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