An electrification method for catalytic dry reforming and a system applying the method
By utilizing the interfacial electrothermal and electronic effects of conductive catalysts, the problems of catalyst sintering and carbon deposition at high temperatures were solved, achieving complete CO2 conversion at low power and reducing energy consumption and process costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NINGBO INST OF MATERIALS TECH & ENG CHINESE ACAD OF SCI
- Filing Date
- 2023-05-30
- Publication Date
- 2026-05-26
AI Technical Summary
Traditional catalytic dry reforming reactions are prone to catalyst sintering and carbon buildup at high temperatures, leading to deactivation. They also have high energy consumption and high process costs.
By employing a conductive catalyst and utilizing the interfacial electrothermal and electronic effects, the catalyst reacts with a mixture of CH4 and CO2 gases through contact with an electrically conductive catalyst, reducing the need for external heating sources and achieving high catalyst activity at low power.
Complete CO2 conversion was achieved at low power, reducing energy consumption, avoiding catalyst sintering and carbon buildup, and lowering process costs.
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Figure CN116902917B_ABST
Abstract
Description
Technical Field
[0001] This application relates to an electrification method for catalytic dry reforming reaction and a system using this method, belonging to the field of energy and environmental technology. Background Technology
[0002] Methane dry reforming can simultaneously convert two major greenhouse gases, CH4 and CO2, and has great potential for industrial applications. However, this reaction often requires high temperatures to achieve effective conversion. Traditional heating reaction temperatures are generally above 700℃ (see Nature, 1991, 352(6332): 225-226.), and side reactions such as reverse water-gas shift and methane cracking can occur at high temperatures. Therefore, it is often necessary to explore suitable catalysts to promote the reaction under high-temperature conditions. However, at high temperatures, catalysts are prone to sintering or carbon buildup on their surface, leading to catalyst deactivation. At the same time, high-temperature endothermic reactions consume a lot of energy, resulting in high process costs. Summary of the Invention
[0003] According to one aspect of this application, an electrification method for catalytic dry reforming is provided. By selecting and using a conductive catalyst, the catalyst activity is enhanced by the interfacial electrothermal effect and interfacial electronic effect, thereby promoting the methane dry reforming reaction that requires high-temperature conditions. This overcomes the problems in the prior art where the catalyst requires an additional heating source, the catalyst is prone to sintering or carbon deposition on the catalyst surface in high-temperature environments, leading to catalyst deactivation, and the high energy consumption of high-temperature endothermic reactions results in significant process costs.
[0004] The technical solution adopted in this application is as follows:
[0005] An electrified method for catalytic dry reforming reaction includes the following steps: contacting an electrically energized conductive catalyst with a mixed gas containing CH4 and CO2 to carry out a dry reforming reaction;
[0006] The conductive catalyst includes a conductive catalytic support, a catalytically active component, and a catalytic promoter;
[0007] The conductive catalytic support is selected from at least one of carbon material support and metal oxide semiconductor material support;
[0008] Optionally, the catalytically active component is selected from at least one of nickel, iron, cobalt, rhodium, ruthenium, palladium, and platinum;
[0009] Optionally, the catalyst is selected from at least one of lanthanum oxide, cerium oxide, cesium oxide, magnesium oxide, and calcium oxide.
[0010] Optionally, the carbon material is selected from at least one of activated carbon, graphite powder, carbon nanotubes, and graphene.
[0011] Optionally, the metal oxide semiconductor material is selected from at least one of antimony-doped tin oxide, tin-doped indium oxide, aluminum-doped zinc oxide, and lanthanide perovskites.
[0012] Optionally, the catalytically active component in the conductive catalyst has a weight fraction of 1-5 wt%.
[0013] Optionally, the weight fraction of the catalytically active component in the conductive catalyst is selected from any value among 1wt%, 2wt%, 3wt%, 4wt%, and 5wt%, or any range between the two.
[0014] Optionally, the molar ratio of the catalytically active component to the catalytic promoter is 1:0.5~5.
[0015] Optionally, the molar ratio of the catalytically active component to the catalytic promoter is selected from any value among 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:2, 1:3, 1:4, and 1:5, or any range between the two.
[0016] Optionally, the volume fractions of CH4 and CO2 in the mixed gas are independently 4-36%.
[0017] Optionally, the mixed gas may also include a carrier gas.
[0018] Optionally, the carrier gas is an inactive gas.
[0019] Optionally, the volume fractions of CH4 and CO2 in the mixed gas are independently selected from any value among 4%, 8%, 12%, 16%, 20%, 25%, 30%, and 36%, or any range between the two.
[0020] Optionally, the volume ratio of CH4 to CO2 is 1:0.1~10.
[0021] Optionally, the volumes of CH4 and CO2 are selected from any value among 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, and 1:10, or any range between the two.
[0022] Optionally, the contact condition is that the mass hourly space velocity (WHSV) of the mixed gas relative to the conductive catalyst is 4.5~36 L·g. -1 cat ·h -1 .
[0023] Optionally, the mass hourly space velocity of the mixed gas relative to the conductive catalyst is selected from 4.5 L·g-1 cat ·h -1 9 L·g -1 cat ·h -1 12 L·g -1 cat ·h -1 16 L·g -1 cat ·h -1 24L·g -1 cat ·h -1 30 L·g -1 cat ·h -1 36 L·g -1 cat ·h -1 Any value in the range, or any value between the two.
[0024] Optionally, the energizing condition is as follows: an electric current is passed through the conductive catalyst, and the power per unit mass of conductive catalyst is 25~1500 W / g.
[0025] Optionally, the power per unit mass of the conductive catalyst is selected from any value among 25 W / g, 550 W / g, 100 W / g, 200 W / g, 400 W / g, 800 W / g, 1200 W / g, and 1500 W / g, or any range between the two.
[0026] A system for electrifying a catalytic dry reforming reaction as described above, the system comprising a reaction chamber, a conductive catalyst, a positive electrode element, and a negative electrode element;
[0027] The conductive catalyst is disposed in the reaction chamber;
[0028] The positive electrode element and the negative electrode element are respectively electrically connected to both ends of the conductive catalyst;
[0029] The reaction chamber is provided with at least one air inlet and at least one air outlet.
[0030] The system is used in conjunction with an electrification method for catalytic dry reforming reactions.
[0031] Optionally, the system may also include a conductive filter element.
[0032] Optionally, the conductive filter element includes a copper filter element.
[0033] A conductive filter element is disposed at both ends of the conductive catalyst, at least for fixing the conductive catalyst.
[0034] The conductive filter element is disposed at both ends of the conductive catalyst and is electrically connected to the positive electrode element and the negative electrode element.
[0035] The positive and negative electrodes are in contact with the conductive filter elements at both ends of the conductive catalyst, thereby achieving electrical connection with the conductive catalyst.
[0036] Optionally, the system further includes a temperature measuring element for measuring the temperature at the contact points between the conductive filter element and the positive and negative electrode elements.
[0037] Optionally, the temperature measuring element includes a thermocouple.
[0038] Optionally, the reaction chamber includes a reaction tube and an insulation layer disposed on the outside of the reaction tube;
[0039] Both ends of the reaction tube are respectively provided with sleeves that are tightly connected to the ends of the reaction tube;
[0040] The reaction tube has an air inlet on one end of the sleeve that communicates with the inner cavity of the sleeve, and an air outlet on the other end of the sleeve that communicates with the inner cavity of the sleeve.
[0041] Optionally, the conductive catalyst is placed inside the reaction tube.
[0042] Optionally, the positive electrode element and the negative electrode element are disposed on the side of the sleeve away from the reaction tube;
[0043] Seal rings are independently provided between the positive electrode element and the bushing, between the negative electrode element and the bushing, and between the bushing and the reaction tube.
[0044] The reaction tube mainly serves as a reaction chamber, where a catalyst fixed by a conductive filter element is placed. The other end has a gas outlet that communicates with the inner cavity of the sleeve. The gas outlet is connected to an online gas detection device for component analysis.
[0045] Optionally, the reaction tube is a quartz tube.
[0046] The conductive catalyst is heated by passing an electric current through it to generate an electrothermal effect. By controlling the input of electrical power, the CO2 conversion rate can reach 100% at low power.
[0047] The technical solution of this application designs and constructs a highly active and stable nano-electrothermal catalyst for the methane-carbon dioxide dry reforming reaction. Active metals such as nickel, iron, cobalt, rhodium, ruthenium, palladium, and platinum are highly efficient catalysts for dry reforming reactions, while catalytic agents such as lanthanum oxide, cerium oxide, cesium oxide, magnesium oxide, and calcium oxide have been proven to adsorb CO2 through acid-base interactions and assist in the oxidation of carbon deposits, thereby enhancing the catalytic effect. The conductive support is selected from nanomaterials with high-temperature tolerance and chemical inertness, such as antimony tin oxide (ATO), indium tin oxide (ITO), or carbon nanotubes. By designing and constructing an electrothermal catalyst system, the interfacial electrothermal and electronic effects are utilized to enhance catalyst activity, thereby promoting the methane dry reforming reaction, which requires high-temperature conditions. Furthermore, an electrified method for catalyzing the methane-carbon dioxide dry reforming reaction is proposed. In the electrically driven catalytic reaction, complete CO2 conversion can be achieved at low power by controlling the input of electrical power.
[0048] The beneficial effects that this application can produce include:
[0049] The electrification method for catalytic dry reforming reaction and the system using the method provided in this application introduce reaction gas containing methane and carbon dioxide into the reaction chamber. In the electrically driven catalytic reaction, the electrothermal effect is generated by the current flowing through the conductive catalyst. By controlling the input of electrical power, the catalytic methane-carbon dioxide dry reforming reaction can be realized at low power and the complete conversion of carbon dioxide can be achieved without an external heat source, thus reducing energy consumption. Attached Figure Description
[0050] Figure 1 This is a graph showing the relationship between CH4 and CO2 conversion rates and power in Example 2 of this application;
[0051] Figure 2 This is a graph showing the relationship between H2 and CO yields and power in Example 2 of this application. Detailed Implementation
[0052] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.
[0053] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.
[0054] Example 1
[0055] A system for an electrified method of catalytic dry reforming reaction includes a reaction tube, a conductive catalyst, a positive electrode element, a negative electrode element, a conductive filter element, and a temperature measuring element.
[0056] The reaction tube serves as the reaction chamber, where a conductive catalyst fixed by a conductive filter element is placed. Each end of the reaction tube has an air inlet and an air outlet.
[0057] The conductive filter element is a copper filter element, which is respectively set at both ends of the conductive catalyst and electrically connected to the positive electrode element and the negative electrode element. Both the positive electrode element and the negative electrode element are made of copper.
[0058] The temperature measuring element is a thermocouple, used to measure the temperature at the contact points between the conductive filter element and the positive and negative electrode elements;
[0059] An insulation layer is installed on the outside of the reaction tube. Sleeves that are tightly connected to the ends of the reaction tube are installed at both ends. An inlet communicating with the inner cavity of the sleeve is provided on one end of the sleeve, and an outlet communicating with the inner cavity of the sleeve is provided on the other end. The positive and negative electrode elements are located on the side of the sleeve away from the reaction tube. Seal rings are independently installed between the positive electrode element and the sleeve, between the negative electrode element and the sleeve, and between the sleeve and the reaction tube. The outlet is connected to an online chromatograph for component analysis.
[0060] Example 2
[0061] In the system of Example 1, the conductive catalyst used was activated carbon as the conductive support, loaded with 2% active metal Ni, and lanthanum oxide as the catalyst promoter, wherein La / Ni = 1:1 (molar ratio). 0.2 g of the catalyst was placed in the reaction chamber, and after purging with He for 40 min, a carrier gas and a reactant gas (volume ratio CH4:CO2 = 1:1) were introduced at a mass hourly space velocity (WHSV) of 9 L·g⁻¹. -1 cat ·h -1 The volume fractions of methane and carbon dioxide in the reaction gases were 20% and 20%, respectively. The initial power was 5W, the final power was 22W, and the constant power output was maintained at (5W, 8W, 10W, 12W, 14W, 16W, 18W, 20W, 22W) for 25 minutes at each power. The gas stream after the reaction was then analyzed by online chromatography. The results showed that at a power of 16W and a temperature of 530.6℃, the CH4 conversion rate was 76.51% and the CO2 conversion rate was 100%.
[0062] Example 3
[0063] In the system of Example 1, the conductive catalyst used was graphene as the conductive support, loaded with 4% active metal Ni, and lanthanum oxide as the catalyst promoter, wherein La / Ni = 2:1 (molar ratio). 0.2 g of the conductive catalyst was placed in the reaction chamber, and after purging with He for 40 min, a carrier gas and a reactant gas (volume ratio CH4:CO2 = 6:1) were introduced, with a mass hourly space velocity (WHSV) of 21 L·g⁻¹. -1 cat ·h -1The volume fractions of methane and carbon dioxide in the reaction gases were 34.29% and 5.71%, respectively. The initial power was 5W, the final power was 16W, and the constant power output (5W, 8W, 10W, 12W, 14W, 16W) was maintained for 25 minutes at each power. The gas stream after the reaction was analyzed by online chromatography. The results showed that at a power of 16W and a temperature of 540℃, the CH4 conversion rate was 33.89% and the CO2 conversion rate was 100%.
[0064] Example 4
[0065] In the system of Example 1, the conductive catalyst used was: aluminum-doped zinc oxide as the conductive support, loaded with 3% active palladium metal, and cerium oxide as the catalyst promoter, wherein Ce / Pd = 3:1 (molar ratio). 0.2 g of the conductive catalyst was placed in the reaction chamber, and after purging with He for 40 min, a carrier gas and a reactant gas (volume ratio CH4:CO2 = 2:1) were introduced, with a mass hourly space velocity (WHSV) of 4.5 L·g⁻¹. -1 cat ·h -1 The volume fractions of methane and carbon dioxide in the reaction gases were 26.67% and 13.33%, respectively. The initial power was 5W, the final power was 16W, and the constant power output (5W, 8W, 10W, 12W, 14W, 16W) was maintained for 25 minutes at each power. The gas stream after the reaction was analyzed by online chromatography. The results showed that at a power of 12W and a temperature of 475.0℃, the CH4 conversion rate was 32.05% and the CO2 conversion rate was 95.92%.
[0066] Example 5
[0067] In the system of Example 1, the conductive catalyst used was antimony-doped tin oxide as the conductive support, loaded with 1% active rhodium metal, and calcium oxide as the catalyst promoter, wherein Ca / Rh = 5:1 (molar ratio). 0.2 g of the conductive catalyst was placed in the reaction chamber, and after purging with He for 40 min, a carrier gas and a reactant gas (volume ratio CH4:CO2 = 8:1) were introduced at a mass hourly space velocity (WHSV) of 36 L·g⁻¹. -1 cat ·h -1 The volume fractions of methane and carbon dioxide in the reaction gases were 35.56% and 4.44%, respectively. The initial power was 5W, the final power was 16W, and the constant power output (5W, 8W, 10W, 12W, 14W, 16W) was maintained for 25 minutes at each power. The gas stream after the reaction was analyzed by online chromatography. The results showed that at a power of 12W and a temperature of 517.20℃, the CH4 conversion rate was 15.36% and the CO2 conversion rate was 93.36%.
[0068] Example 6
[0069] In the system of Example 1, the conductive catalyst used was: carbon nanotubes as the conductive support, loaded with 5% active metal ruthenium, and magnesium oxide as the catalyst promoter, wherein Mg / Rh = 4:1 (molar ratio). 0.2 g of the conductive catalyst was placed in the reaction chamber, and after purging with He for 40 min, a carrier gas and a reactant gas (volume ratio CH4:CO2 = 4:1) were introduced, with a mass hourly space velocity (WHSV) of 21 L·g⁻¹. -1 cat ·h -1 The volume fractions of methane and carbon dioxide in the reaction gases were 32% and 8%, respectively. The initial power was 5W, the final power was 16W, and the constant power output (5W, 8W, 10W, 12W, 14W, 16W) was maintained for 25 minutes at each power. The gas stream after the reaction was sent to online chromatography for analysis. The results showed that at a power of 16W and a temperature of 540℃, the CH4 conversion rate was 33.66% and the CO2 conversion rate was 100%.
[0070] Example 7
[0071] In the system of Example 1, the conductive catalyst used was lanthanide perovskite nickelate. 0.2 g of the conductive catalyst was placed in the reaction chamber, and after purging with He for 40 min, a carrier gas and a reactant gas (volume ratio CH4:CO2 = 9:1) were introduced at a mass hourly space velocity (WHSV) of 27 L·g⁻¹. -1 cat ·h -1 The volume fractions of methane and carbon dioxide in the reaction gases were 36% and 4%, respectively. The initial power was 5W, the final power was 16W, and the constant power output (5W, 8W, 10W, 12W, 14W, 16W) was maintained for 25 minutes at each power. The gas stream after the reaction was sent to online chromatography for analysis. The results showed that at a power of 16W and a temperature of 540℃, the CH4 conversion rate was 12.89% and the CO2 conversion rate was 100%.
[0072] Example 8
[0073] In the system of Example 1, the conductive catalyst used was: indium tin-doped oxide as the conductive support, loaded with 1% active metal Fe, and cerium oxide as the catalyst promoter. 0.2 g of the conductive catalyst was placed in the reaction chamber, and after purging with He for 40 min, a carrier gas and a reactant gas (volume ratio CH4:CO2 = 1:2) were introduced at a mass hourly space velocity (WHSV) of 9 L·g⁻¹. -1 cat ·h -1The volume fractions of methane and carbon dioxide in the reaction gases were 13.33% and 26.67%, respectively. The initial power was 5W, the final power was 16W, and the constant power output (5W, 8W, 10W, 12W, 14W, 16W) was maintained for 25 minutes at each power. The gas stream after the reaction was analyzed by online chromatography. The results showed that at a power of 12W and a temperature of 481.3℃, the CH4 conversion rate was 60% and the CO2 conversion rate was 82.57%.
[0074] Example 9
[0075] In the system of Example 1, the conductive catalyst used was: carbon nanotubes as the conductive support, loaded with 1% active metal Co, and cesium oxide as the catalyst promoter, wherein Cs / Fe = 1:1 (molar ratio). 0.2 g of the conductive catalyst was placed in the reaction chamber, and after purging with He for 40 min, a carrier gas and a reactant gas (volume ratio CH4:CO2 = 1:5) were introduced, with a mass hourly space velocity (WHSV) of 27 L·g⁻¹. -1 cat ·h -1 The volume fractions of methane and carbon dioxide in the reaction gases were 6.67% and 33.33%, respectively. The initial power was 5W, the final power was 16W, and constant power output (5W, 8W, 10W, 12W, 14W, 16W) was maintained for 25 minutes at each power. The gas stream after the reaction was analyzed by online chromatography. The results showed that at a power of 10W and a temperature of 430.40℃, the CH4 conversion rate was 90.34% and the CO2 conversion rate was 40.66%.
[0076] Example 10
[0077] In the system of Example 1, the conductive catalyst used was activated carbon as the conductive support, loaded with 4% active metal Ni, and lanthanum oxide as the catalyst promoter, wherein La / Ni = 2:1 (molar ratio). 0.2 g of the conductive catalyst was placed in the reaction chamber, and after purging with He for 40 min, a carrier gas and a reactant gas (volume ratio CH4:CO2 = 1:9) were introduced at a mass hourly space velocity (WHSV) of 18 L·g⁻¹. -1 cat ·h -1 The volume fractions of methane and carbon dioxide in the reaction gases were 4% and 36%, respectively. The initial power was 5W, the final power was 16W, and the constant power output (5W, 8W, 10W, 12W, 14W, 16W) was maintained for 25 minutes at each power. The gas stream after the reaction was analyzed by online chromatography. The results showed that at a power of 10W and a temperature of 466.40℃, the CH4 conversion rate was 92.43% and the CO2 conversion rate was 43.27%.
[0078] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.
Claims
1. An electrification method for a catalytic dry reforming reaction, characterized in that, By designing and constructing an electrothermal catalyst system, the catalyst activity is enhanced by the interfacial electrothermal effect and interfacial electronic effect, thereby promoting the dry reforming reaction of methane that requires high temperature conditions. The process includes the following steps: contacting an electrically charged conductive catalyst with a mixed gas containing CH4 and CO2 to carry out the dry reforming reaction. The conductive catalyst includes a conductive catalytic support, a catalytically active component, and a catalytic promoter; The conductive catalytic support is selected from at least one of carbon material support and metal oxide semiconductor material support; The catalytically active component is selected from at least one of nickel, iron, cobalt, rhodium, ruthenium, palladium, and platinum; The catalyst is selected from at least one of lanthanum oxide, cerium oxide, cesium oxide, magnesium oxide, and calcium oxide; The conditions for energizing are: an electric current is passed into the conductive catalyst, and the power per unit mass of conductive catalyst is 25~1500 W / g.
2. The electrification method for the catalytic dry reforming reaction according to claim 1, characterized in that, The carbon material is selected from at least one of activated carbon, graphite powder, carbon nanotubes, and graphene. The metal oxide semiconductor material is selected from at least one of antimony-doped tin oxide, tin-doped indium oxide, aluminum-doped zinc oxide, and lanthanide perovskite. The conductive catalyst contains 1-5 wt% of the catalytically active component. The molar ratio of the catalytically active component to the catalytic promoter is 1:0.5~5.
3. The electrification method for the catalytic dry reforming reaction according to claim 1, characterized in that, The volume fractions of CH4 and CO2 in the mixed gas are independently 4-36%.
4. The electrification method for the catalytic dry reforming reaction according to claim 1, characterized in that, The volume ratio of CH4 to CO2 in the mixed gas is 1:0.1~10.
5. The electrification method for the catalytic dry reforming reaction according to claim 1, characterized in that, The contact conditions are as follows: the mass hourly space velocity (MSV) of the mixed gas relative to the conductive catalyst is 4.5–36 L·g. -1 cat ·h -1 .
6. A system for applying the electrification method of the catalytic dry reforming reaction according to any one of claims 1 to 5, characterized in that, The system includes a reaction chamber, a conductive catalyst, a positive electrode element, and a negative electrode element; The conductive catalyst is disposed in the reaction chamber; The positive electrode element and the negative electrode element are respectively electrically connected to both ends of the conductive catalyst; The reaction chamber is provided with at least one air inlet and at least one air outlet.
7. The system according to claim 6, characterized in that, The system also includes a conductive filter element; The conductive filter element is disposed at both ends of the conductive catalyst and is electrically connected to the positive electrode element and the negative electrode element.
8. The system according to claim 7, characterized in that, The system also includes a temperature measuring element for measuring the temperature at the contact points between the conductive filter element and the positive and negative electrode elements.
9. The system according to claim 6, characterized in that, The reaction chamber includes a reaction tube and an insulation layer disposed on the outside of the reaction tube; Both ends of the reaction tube are respectively provided with sleeves that are tightly connected to the ends of the reaction tube; The reaction tube has an air inlet on one end of the sleeve that communicates with the inner cavity of the sleeve, and an air outlet on the other end of the sleeve that communicates with the inner cavity of the sleeve.
10. The system according to claim 9, characterized in that, The positive electrode element and the negative electrode element are disposed on the side of the sleeve away from the reaction tube; Seal rings are independently provided between the positive electrode element and the bushing, between the negative electrode element and the bushing, and between the bushing and the reaction tube.