CN113307225A - Method for preparing hydrogen by stably catalyzing methane cracking through carbon black enhanced activated carbon and application - Google Patents
Method for preparing hydrogen by stably catalyzing methane cracking through carbon black enhanced activated carbon and application Download PDFInfo
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Abstract
本发明公开了了一种利用炭黑增强活性炭稳定催化甲烷裂解制氢的方法与应用。该方法采用8~16目椰壳活性炭为载体负载炭黑，经过一系列制备流程将两种碳催化剂相结合，于850~1000℃常压下反应。该方法有效提高了单一活性炭催化剂催化甲烷裂解制氢的转化率，使活性炭催化剂具有更高的初始转化率并表现出延缓失活的效果，这将是一种有效提高廉价活性炭催化活性的方法。本发明对碳催化剂催化甲烷裂解制氢工业应用及提升甲烷裂解转化率具有重要的应用价值。
The invention discloses a method and application of using carbon black to enhance activated carbon to stably catalyze methane cracking to produce hydrogen. In the method, 8-16 mesh coconut shell activated carbon is used as a carrier to support carbon black, and two carbon catalysts are combined through a series of preparation processes, and the reaction is carried out under normal pressure at 850-1000 °C. The method effectively improves the conversion rate of single activated carbon catalyst to catalyze methane cracking to hydrogen production, makes the activated carbon catalyst have a higher initial conversion rate and shows the effect of delaying deactivation, which will be an effective method to improve the catalytic activity of cheap activated carbon. The invention has important application value for industrial application of carbon catalyst catalyzing methane cracking to produce hydrogen and improving the conversion rate of methane cracking.
Description
Technical Field
The invention relates to the technical field of hydrogen production by methane cracking, in particular to a method for stably catalyzing hydrogen production by methane cracking by using carbon black reinforced activated carbon and application thereof.
Background
Climate change and energy depletion are serious challenges facing the world, and as the population increases, the energy demand will also continuously increase, and the development of efficient clean energy is imperative. The hydrogen energy is the most promising energy form, and has the great advantages of high heat value, no pollution and reproducibility. Methane is the main component of natural gas and is the most commonly used raw material for large-scale industrial hydrogen production. The production of hydrogen from methane is typically carried out by steam reforming or partial oxidation.
CH4+H2O＝CO+3H2
Although the natural gas reforming is industrially applied and the technology is relatively mature, on one hand, the method can cause a large amount of carbon dioxide emission and is not beneficial to greenhouse gas emission reduction; on the other hand, the reaction requires a large amount of heat to be absorbed, and the energy consumption is high. Therefore, in recent years, hydrogen production by methane cracking is widely researched as a low-energy-consumption and low-emission hydrogen production method, and is the most promising hydrogen production method at present. Because the methane property is stable and the temperature of the non-catalytic cracking is more than 1500 ℃, the catalytic cracking of the methane becomes a research hotspot. The catalyst can greatly reduce the temperature required by the reaction and improve the hydrogen yield.
The direct cracking of methane to produce hydrogen is one clean hydrogen producing process, and methane is decomposed into hydrogen and carbon at high temperature without producing CO2The method is a transition process for connecting fossil fuel and renewable energy. The methane cracking reaction is an endothermic reaction, the energy consumed for generating hydrogen is 37.8kJ/mol, C-H in methane molecules is very stable, the cracking rate of the non-catalytic methane cracking reaction is very low below 1000 ℃, and the reaction temperature can be greatly reduced and the hydrogen yield can be improved during catalytic cracking. Generally, the cracking process of methane molecules on a catalyst starts from the dissociative adsorption of methane on active sites, then a series of surface dissociation reactions occur, and finally elemental carbon and hydrogen are formed, and the specific mechanism is as follows:
first, the methane molecule is adsorbed by the active sites of the catalyst and is cleaved to form a hydrogen atom and a methyl radical:
(CH4)g→(CH3)a+(H2)a
then, the methyl radicals undergo a gradual dissociation and eventually form carbon and hydrogen:
(CH3-x)a→(CH2-x)a+(H)a
(C)a→1/n(Cn)c(growth of carbon grains)
2(H)a→(H2)g(formation of Hydrogen gas)
At present, the research of hydrogen production by methane cracking mainly focuses on the research of catalysts which are efficient, easy to obtain, low in price and high in stability, metal catalysts are high in catalytic activity, good in stability and high in catalytic methane cracking conversion rate, but the metal catalysts are high in cost, in addition, carbon nanotubes (CNTs or CNFs) can be formed in the catalytic process of the metal catalysts, the carbon tubes push away metal particles with catalytic activity from the surface of a carrier, and the carbon deposition is removed by using steam in the regeneration process, so that the metal particles fall off, the catalyst structure is damaged, and the metal catalysts are difficult to regenerate.
The carbon-based catalyst does not have the problem, no metal carbide is generated in the process of catalyzing methane cracking, carbon deposition generated on the surface can be removed by using high-temperature steam, the catalyst regeneration is realized, and the utilization rate is greatly improved. The carbon-based catalyst has low price, wide raw material source, high temperature resistance, sulfur resistance and other toxic impurities resistance. In carbon-based catalysts, activated carbon and carbon black show wide application prospects, but have some problems to be improved, for example, although the activated carbon catalyst has high initial activity, rapid inactivation and low later activity, the carbon black catalyst has stable catalytic activity but low initial catalytic conversion rate. These two different reaction tendencies are closely related to the reaction form in which carbon deposits grow on the catalyst surface. The carbon-deposited graphite layers on the surface of the active carbon are arranged compactly and regularly, and the defect sites of the original active carbon are occupied by the carbon deposition to disappear, so that the active carbon no longer has catalytic activity; unlike activated carbon surface carbon deposition, defective carbon black and its surface carbon deposition consist of disordered graphite layers rich in structural defects, methane molecules dissociate by the interaction of chemical reaction vacancies in the graphite layers and graphite layer edge defects, in this process, the C-H bonds in the methane molecules break, new C-C bonds are formed in the hexagons of the carbon, and the catalytically active sites at the edges of the graphite layers can be regenerated by depositing carbon decomposed by methane at the edges of the graphite layers, thereby enabling the carbon black to exhibit stable catalytic properties.
From the foregoing, compared with metal catalysts, carbon catalysts have many advantages of low price, wide sources, and inactivation and regeneration, and become methane cracking hydrogen production catalysts with more development potential, and activated carbon and carbon black are widely studied in carbon catalysts. Although a great deal of research is carried out on a single activated carbon catalyst, the problem of rapid inactivation in the initial stage is not solved, and along with the reaction, carbon generated by methane cracking is attached to the surface of the activated carbon to cover the active sites of the catalyst, so that the catalyst is continuously inactivated until the catalytic activity is completely lost. The single carbon black catalyst has a stable catalytic effect, but its initial performance is low. Therefore, the prior art has the following defects:
1. the metal-based catalyst has high cost and cannot be regenerated; this is because the metal-based catalysts often use more expensive metals to obtain higher catalytic ability, which makes the cost higher, and in addition, the preparation process of the metal-based catalysts is cumbersome, which increases the cost thereof. Failure to regenerate is due to the removal of the soot which destroys the catalyst structure.
2. The pure active carbon catalyst is quickly deactivated, and the catalytic efficiency is lower. This is because the initial catalytic efficiency of the activated carbon catalyst is high, so that carbon deposition is rapid, which results in coverage of surface active sites, thereby rapid deactivation, and the catalytic efficiency is also rapidly decreased.
3. Although the pure carbon black catalyst has a stable catalytic effect, the initial performance is low, and the overall catalytic effect is low.
Chinese patent CN106865498B discloses a method for preparing hydrogen and fibrous carbon by using carbon material as catalyst. The method comprises the steps of taking a mixed gas containing methane and hydrogen as a raw material, taking a carbon material as a catalyst, and reacting at 600-1200 ℃ under normal pressure, wherein the hydrogen accounts for 1% -90% of the total amount of the mixed gas. The method improves the stability of the carbon material for catalyzing the methane cracking to prepare hydrogen.
Chinese patent CN111689467A discloses a method for preparing hydrogen by cracking methane with activated carbon as a catalyst, wherein methane is used as a raw material, a trace amount of hydrogen sulfide is added, the activated carbon is used as the catalyst, and the reaction is carried out at 900-950 ℃ under normal pressure to obtain hydrogen and carbon products, wherein the concentration of the hydrogen sulfide is 100ppm-300 ppm. According to the invention, trace hydrogen sulfide is added into the methane raw material gas, so that the activity of the activated carbon for catalyzing methane to crack for producing hydrogen is improved, and the inactivation time of the activated carbon catalyst is prolonged.
In the two patent methods, single activated carbon is used as a catalyst, and from the perspective of raw material gas, other gases are added to enhance the catalytic activity of the activated carbon catalyst, the promotion effect is determined by the added gases, and the activity of the activated carbon catalyst is not improved.
How to combine the advantages of two carbon catalysts to prepare a high-efficiency, stable and low-cost carbon catalyst is a problem to be solved urgently.
Disclosure of Invention
Aiming at the problem that single activated carbon is used as a catalyst and is inactivated rapidly, the invention provides a method for preparing hydrogen by stably catalyzing methane cracking by using carbon black reinforced activated carbon, the method adopts 8-16-mesh coconut shell activated carbon as a carrier to load carbon black, two carbon catalysts are combined through a series of preparation processes, and the reaction is carried out at the temperature of 850-1000 ℃ under normal pressure. The method starts from the catalyst, and utilizes the carbon black with stable catalytic activity to modify the activated carbon to obtain the carbon-carbon composite catalyst, so that the conversion rate of the single activated carbon catalyst for catalyzing the cracking of methane to prepare hydrogen is effectively improved, the activated carbon catalyst has higher initial conversion rate and shows the effect of delaying inactivation, and the method is a method for effectively improving the catalytic activity of the cheap activated carbon. The invention has important application value for industrial application of the carbon catalyst in catalyzing methane cracking hydrogen production and improving methane cracking conversion rate.
A method for preparing hydrogen by stably catalyzing methane cracking by using carbon black reinforced activated carbon comprises the following steps:
step 1, washing and drying active carbon, and adding 30% HNO3Soaking in the solution for 12-24h, washing activated carbon with ultrapure water until the filtrate is neutral, and drying to obtain acid-washed activated carbon;
step 2, dissolving a dispersant in water to prepare a dispersant aqueous solution, then directly adding carbon black, performing ultrasonic oscillation and mechanical stirring simultaneously for more than 0.5h to obtain a carbon black dispersion, wherein the mass ratio of the carbon black to the dispersant is 5-10: 1;
step 3, putting the activated carbon after the acid washing into the carbon black dispersion liquid for mixing, mechanically stirring for 0.5-1.5h while ultrasonically vibrating, screening out the activated carbon, and drying;
and 4, calcining the dried activated carbon for at least 3 hours at the temperature of 900-1000 ℃ in an inert atmosphere to obtain the activated carbon loaded carbon black catalyst.
The improvement is that the mass ratio of the activated carbon to the carbon black is 20: 3-5.
The improvement is that the active carbon is 8-16 mesh coconut shell active carbon, and the carbon black is BP 2000.
The improvement is that the dispersant is sodium dodecyl propane sulfonate.
The activated carbon loaded carbon black catalyst prepared by the method is applied to catalyzing methane cracking to prepare hydrogen.
As an improvement, the application comprises the following steps:
step one, placing an activated carbon loaded carbon black catalyst into a reaction quartz tube, fixing two sides of the activated carbon loaded carbon black catalyst by quartz wool, and heating to 850-1000 ℃ in an inert atmosphere;
secondly, the reaction temperature is kept, the hydrogen is produced by switching the methane gas catalysis, and the methane airspeed is 400-800 h-1；
Thirdly, the reacted gas enters a gas analyzer for gas component analysis, and the gas analyzer starts to record data when detecting the hydrogen;
and fourthly, closing the reactor after the experiment is finished, and cooling the reactor to the room temperature.
In a further improvement, the methane space velocity of the second step is 600h-1。
In a further improvement, the reactor is a quartz tube fixed bed reactor or a circulating fluidized bed reactor.
Has the advantages that:
compared with the prior art, the method for preparing hydrogen by stably catalyzing methane cracking by using carbon black reinforced activated carbon and the application thereof effectively improve the conversion rate of preparing hydrogen by catalyzing methane cracking by using a single activated carbon catalyst, so that the activated carbon catalyst has higher initial conversion rate and shows the effect of delaying inactivation, and the method is a method for effectively improving the catalytic activity of cheap activated carbon. The method has important application values in industrial application of catalyzing methane cracking hydrogen production by the carbon catalyst and improving the methane cracking conversion rate, and experiments show that the activated carbon catalyst modified by the carbon black obviously has higher catalytic activity in the activated carbon non-inactivation stage, and can improve the methane conversion rate by about 10%. The specific advantages are as follows:
1. the active carbon is used as a catalyst carrier, so that the catalyst is cheap and easy to obtain, the production cost is low, and the economy is high;
2. the carbon-carbon composite catalyst is obtained by adopting carbon black loading and an active carbon carrier, and has the advantages of regeneration, high temperature resistance, sulfur resistance, other toxic impurities resistance and the like of a carbon material as the catalyst;
3. the activated carbon loaded carbon black catalyst can simultaneously have the performance advantages of activated carbon and carbon black, obtain a catalyst with higher initial activity and higher stability, improve the catalytic activity of the activated carbon and delay the inactivation time of the catalyst.
Drawings
FIG. 1 is a flow diagram of the catalyst preparation of the present invention;
FIG. 2 is a flow diagram of catalytic cracking of methane;
FIG. 3 is a graph of activated carbon loaded carbon black methane conversion;
FIG. 4 is the average methane conversion;
FIG. 5 is an SEM photograph of activated carbon, wherein (A) is before reaction of AC, (B) is after reaction of AC at 950 ℃, (C) is before reaction of AC + BP2000, (D) is after reaction of AC + BP2000 at 950 ℃;
FIG. 6 is a graph of activated carbon and carbon black methane conversion.
Detailed Description
Reference will now be made in detail to various exemplary embodiments of the invention, the detailed description should not be construed as limiting the invention but as a more detailed description of certain aspects, features and embodiments of the invention.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference herein for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.
Example 1
A method for preparing hydrogen by stably catalyzing methane cracking by using carbon black reinforced activated carbon, namely a preparation process of a catalyst is shown in figure 1.
Cleaning activated carbon catalyst, oven drying, adding 30% HNO3Soaking in the solution for 12h, washing the activated carbon with ultrapure water until the filtrate is neutral, and drying;
30ml of ultrapure water is added into every 1g of carbon black to be uniformly dispersed,
0.5g of dispersant is put into 150ml of ultrapure water to be uniformly mixed;
mixing the carbon black solution and the sodium dodecyl propane sulfonate dispersant according to the volume ratio of 10:1, and carrying out ultrasonic oscillation for 0.5h while mechanically stirring to prepare a carbon black dispersion liquid;
according to the mass ratio of 20: 5, mixing, carrying out ultrasonic oscillation and mechanical stirring for 1 hour, screening out the activated carbon, and drying;
drying the activated carbon at 1000 ℃ under N2Calcining for 3 hours in atmosphere to obtain the activated carbon loaded carbonA black catalyst.
For comparison, the same amount of single activated carbon was taken at 1000 ℃ N2And (4) atmosphere calcination.
Example 2
A method for preparing hydrogen by stably catalyzing methane cracking by using carbon black reinforced activated carbon, namely a preparation process of a catalyst is shown in figure 1.
Cleaning activated carbon catalyst, oven drying, adding 30% HNO3Soaking in the solution for 12h, washing the activated carbon with ultrapure water until the filtrate is neutral, and drying;
50ml of ultrapure water is added into every 1g of carbon black to be uniformly dispersed,
0.5g of dispersant is put into 150ml of ultrapure water to be uniformly mixed;
mixing the carbon black solution and the sodium dodecyl propane sulfonate dispersant according to the volume ratio of 6:1, and carrying out ultrasonic oscillation for 0.5h while mechanically stirring to prepare a carbon black dispersion liquid;
according to the mass ratio of 20: 3, mixing, mechanically stirring for 1 hour while ultrasonically shaking, screening out the activated carbon, and drying;
drying the activated carbon at 1000 ℃ under N2Calcining for 3h in the atmosphere to obtain the activated carbon loaded carbon black catalyst.
For comparison, the same amount of single activated carbon was taken at 1000 ℃ N2And (4) atmosphere calcination.
Example 3
Except that the mass ratio of the activated carbon to the carbon black is 20: 4, the same as example 1.
Example 4
The catalyst prepared in example 1 is used for catalytic methane cracking reaction at four temperatures of 850, 900, 950 and 1000 ℃, and the reaction flow chart is shown in figure 2. The methane cracking reaction is carried out in a tubular furnace and is heated by a thermocouple.
2g of activated carbon-supported carbon black catalyst was placed in a quartz tube with an inner diameter of 20mm, both sides were fixed with quartz wool, and the catalyst was placed in a nitrogen atmosphere2Heating to reaction temperature under the protection of atmosphere, wherein the heating rate is 15 ℃/min, switching methane gas to start an experiment after the set temperature is reached, and the methane gasThe volume flow rate was 40ml/min and the gas flow rate was 40 ml/min. And (3) after the reaction, the gas enters a gas analyzer for gas component analysis, the gas component data is read by a computer, and the data is recorded when the gas analyzer detects hydrogen.
The methane conversion efficiency (see the following formula) was calculated from the ratio of outlet hydrogen to methane as a basis for determining the catalyst activity. The methane conversion rates of the single activated carbon and the activated carbon-supported carbon black catalyst were calculated separately for comparison.
CH4/％＝100*(([H2]out/2)/([CH4]out+[H2]out/2))
The experimental result is shown in fig. 3, the experimental conditions are named as catalyst + temperature, for example, "AC + BP 2000850" is the reaction of activated carbon supported carbon black catalyst at 850 ℃.
As can be seen from fig. 3, the catalytic performance of the activated carbon at a single temperature point shows a tendency from high to low with increasing reaction time, and the initial conversion is higher. The catalytic performance of the activated carbon loaded carbon black catalyst is obviously improved, the inactivation time at 1000 ℃ is obviously prolonged, and the loaded carbon black can obviously improve the catalytic activity of the activated carbon, so that the average conversion rate of methane at the non-inactivated stage is improved by about 10 percent, as shown in figure 4.
The surface morphology of the activated carbon was examined using a scanning electron microscope to observe the loading of the carbon black, as shown in fig. 5. As can be seen from fig. 5, the carbon black-unloaded activated carbon (fig. 5(a)) had a smooth surface, a clear edge angle, and clear pores; after the carbon black treatment (fig. 5(C)), the surface of the activated carbon was clearly covered with the carbon black and the coverage was uniform. BP2000 carbon black is in a micro spherical shape, the particle size is about 15nm, after dispersion, carbon black particles are uniformly dispersed to cover the surface and holes of the activated carbon, and the covered holes of the activated carbon are not clear any more and are basically and completely covered by the carbon black. After the activated carbon catalyzes the methane cracking reaction (figure 5(B)), a large number of carbon nanotubes are generated on the surface, the diameter of each carbon nanotube is about 0.5-0.8 micrometer, the carbon nanotubes completely cover the holes of the activated carbon, so that the holes are blocked, and the active sites are covered, so that the activated carbon gradually loses catalytic activity; the carbon nanotubes are also generated on the surface of the activated carbon-supported carbon black after the catalytic reaction (fig. 5(D)), but the total number of the carbon nanotubes is much less than that of the activated carbon-supported carbon black after the reaction, and the generated carbon nanotubes have a small diameter, and the generated morphology of the deposited carbon except the carbon nanotubes is mostly spherical or blocky carbon protrusions and is not developed into the carbon nanotubes.
The catalytic performance of activated carbon and BP2000 carbon black at 900 ℃ was investigated by experiments, and the results are shown in FIG. 8. The difference of the catalytic performances of the activated carbon and the carbon black can be obviously seen in the figure, the activated carbon has extremely high initial activity but the catalytic performance is rapidly reduced, and the conversion rate of the inactivated methane is low; carbon black has a low initial conversion but high catalytic stability and stable later performance.
Experiments show that the carbon black loaded on the activated carbon can enable the catalyst to have both high initial activity of the activated carbon and stability of the carbon black, and a carbon-carbon composite catalyst with higher activity is obtained.
Example 5
The catalysts prepared in example 2 and example 3 are respectively subjected to catalytic methane cracking reaction at four temperatures of 850, 900, 950 and 1000 ℃, and the reaction flow chart is shown in figure 2.
The activated carbon-supported carbon black catalyst prepared in example 2 was examined. Namely, the methane cracking reaction is carried out in a tubular furnace and is heated by a thermocouple.
2g of activated carbon-supported carbon black catalyst was placed in a quartz tube with an inner diameter of 20mm, both sides were fixed with quartz wool, and the catalyst was placed in a nitrogen atmosphere2And (3) heating to the reaction temperature under the atmosphere protection, wherein the heating rate is 15 ℃/min, switching methane gas to start an experiment after the set temperature is reached, and the flow rate of the methane gas is 40 ml/min. And (3) after the reaction, the gas enters a gas analyzer for gas component analysis, the gas component data is read by a computer, and the data is recorded when the gas analyzer detects hydrogen.
The methane conversion efficiency (see the following formula) was calculated from the ratio of outlet hydrogen to methane as a basis for determining the catalyst activity. The methane conversion rates of the single activated carbon and the activated carbon-supported carbon black catalyst were calculated separately for comparison.
CH4/％＝100*(([H2]out/2)/([CH4]out+[H2]out/2))
The experimental results are shown in fig. 6 and 7, the experimental conditions are named as catalyst + temperature, for example, "AC + BP 2000850" is the reaction of activated carbon supported carbon black catalyst at 850 ℃.
As can be seen from fig. 6 to 7, the mass ratio of activated carbon to carbon black is 20: 3, the activity of the catalyst prepared by the method is improved more obviously, the improvement amount of the average conversion rate is more than 19%, and therefore, the method for preparing the catalyst can be applied to mixing of activated carbon and carbon black in different proportions, and the effect is obvious.
In conclusion, the method effectively improves the conversion rate of the single activated carbon catalyst for catalyzing the methane cracking to produce hydrogen, so that the activated carbon catalyst has higher initial conversion rate and shows the effect of delaying deactivation, and the method is a method for effectively improving the catalytic activity of the cheap activated carbon. The method has important application values in industrial application of catalyzing methane cracking hydrogen production by the carbon catalyst and improving the methane cracking conversion rate, and experiments show that the activated carbon catalyst modified by the carbon black obviously has higher catalytic activity in the activated carbon non-inactivation stage, and can improve the methane conversion rate by about 10%.
The above description is only a preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, and any simple modifications or equivalent substitutions of the technical solutions that can be obviously obtained by those skilled in the art within the technical scope of the present invention are within the scope of the present invention.
Claims (7)
1. A method for preparing hydrogen by stably catalyzing methane cracking through carbon black enhanced activated carbon is characterized by comprising the following steps:
step 1, washing and drying active carbon, and adding 30% HNO3Soaking in the solution for 12-24h, washing activated carbon with ultrapure water until the filtrate is neutral, and drying to obtain acid-washed activated carbon;
step 2, dissolving a dispersant in water to prepare a dispersant aqueous solution, then directly adding carbon black, performing ultrasonic oscillation and mechanical stirring simultaneously for more than 0.5h to obtain a carbon black dispersion, wherein the mass ratio of the carbon black to the dispersant is 5-10: 1;
step 3, putting the activated carbon after the acid washing into the carbon black dispersion liquid for mixing, mechanically stirring for 0.5-1.5h while ultrasonically vibrating, screening out the activated carbon, and drying;
and 4, calcining the dried activated carbon for at least 3 hours at the temperature of 900-1000 ℃ in an inert atmosphere to obtain the activated carbon loaded carbon black catalyst.
2. The method for preparing hydrogen by stably catalyzing methane cracking through carbon black enhanced activated carbon according to claim 1, wherein the mass ratio of the activated carbon to the carbon black is 20: 3-5.
3. The method for preparing hydrogen by stably catalyzing methane cracking through carbon black-enhanced activated carbon according to claim 1, wherein the activated carbon is 8-16 mesh coconut shell activated carbon, and the carbon black is BP 2000.
4. The method for preparing hydrogen by stably catalyzing methane cracking through carbon black-enhanced activated carbon according to claim 1, wherein the dispersant is sodium dodecyl propane sulfonate.
5. The application of the activated carbon-supported carbon black catalyst prepared according to the method 1 in catalyzing methane cracking to prepare hydrogen.
6. Use according to claim 5, characterized in that it comprises the following steps:
step one, placing an activated carbon loaded carbon black catalyst into a reaction quartz tube, fixing two sides of the activated carbon loaded carbon black catalyst by quartz wool, and heating to 850-1000 ℃ in an inert atmosphere;
and step two, preserving heat after the reaction temperature is reached, and switching methane gas to catalyze and produce hydrogen at the methane airspeed of 400-800 h-1；
Thirdly, the reacted gas enters a gas analyzer for gas component analysis, and the gas analyzer starts to record data when detecting the hydrogen;
fourthly, closing the reactor after the experiment is finished, and cooling the reactor to room temperature
The use of claim 5, wherein the further improvement is that the methane space velocity of the second step is 600h-1。
7. Use according to claim 5, wherein the reactor is a quartz tube fixed bed reactor or a circulating fluidized bed reactor.
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Citations (8)
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