A method for preparing carbon fiber and hydrogen by catalytic cracking of low-carbon hydrocarbons

Abstract

A method for preparing carbon fiber and hydrogen through catalytic cracking of low-carbon hydrocarbons. By prefabricating a mixture of carbonaceous materials and modifiers, as a catalyst for the catalytic cracking reaction of low-carbon hydrocarbons, the design and construction of "gas (reaction gas: low-carbon hydrocarbons)- The solid (carbonaceous material)-solid (modifier) ​​three-phase system uses the activation effect of the modifier on the carbonaceous material to significantly improve and strengthen the catalytic activity of the carbonaceous material towards low-carbon hydrocarbons, and at the same time promote the low-carbon hydrocarbons. The cracked carbon deposits are formed and converted into the form of carbon fibers, thereby achieving the purpose of catalytically cracking low-carbon hydrocarbons to simultaneously produce carbon fibers and hydrogen. It has the characteristics of wide application range of raw materials, simple catalyst preparation, high hydrogen purity, good carbon fiber quality, and easy recovery of modifiers.

Description

technical field

[0001] The invention belongs to the field of conversion and utilization of low-carbon hydrocarbons, in particular to a method for preparing carbon fibers and hydrogen by catalytic cracking of low-carbon hydrocarbons. Background technique

[0002] The catalytic methane cracking hydrogen production process has a simple process, the products are only gaseous hydrogen and solid carbon, the products are easy to separate, and there is no CO or CO 2 It is a hydrogen production process with broad prospects. Compared with the current industrialized methane steam reforming hydrogen production process, the catalytic methane cracking hydrogen production process reduces the water-gas shift and CO 2 The processing steps simplify the process flow; and no high pressure is required, and the requirements for equipment are relatively low. At the same time, the carbon deposits (such as carbon fibers, carbon nanotubes, etc.) generated by it have broad market prospects, thereby ...

Examples

Embodiment 1

[0034] Get semi-coke from Yulin, northern Shaanxi (the bulk semi-coke of Wuzhou Coal Chemical Co., Ltd., Shenmu County, see Table 1 for industrial analysis and elemental analysis, it belongs to a kind of low-temperature pyrolysis semi-coke in coal, the same below) as the raw material for catalyst preparation , crushed and sieved into particles of 70-150 μm. According to the mass ratio of 1:1, weigh the semi-coke particles and Na 2 CO 3 (analytical pure), and simultaneously added to the water-ethanol binary solution (the volume ratio of water and ethanol is 5:1), stirred and mixed for 10 h, and then vacuum-dried to form a mixture.

[0035] Then, take the above-mentioned mixture that is 5g in quality and use it as a catalyst for catalytic methane cracking reaction, and react in a traditional fixed-bed reactor. 300L / (h·g cat ). Collect the gas generated by methane cracking reaction to obtain hydrogen-rich gas; under this condition, within 10 hours of reaction, the methane con...

Embodiment 2

[0040] The semi-coke from Yulin in northern Shaanxi is used as the raw material for catalyst preparation, which is crushed and sieved into particles of 180-300 μm. According to the mass ratio of 1:5, weigh the semi-coke particles and K 2 CO 3 (analytical pure), and simultaneously added to the water-ethanol binary solution (the volume ratio of water and ethanol is 5:1), stirred and mixed for 10 h, and then vacuum-dried to form a mixture.

[0041] Then, take the above-mentioned mixture that is 5g and use it as a catalyst for catalytic methane cracking reaction, and react in a traditional fixed-bed reactor. 100L / (h·g cat ). Collect the gas generated by methane cracking reaction to obtain hydrogen-rich gas; under this condition, within 5 hours of reaction, the methane conversion rate is 88% to 93%, and the hydrogen gas fraction in the reaction gas is 90.3% to 94.7%; After the reaction residue in the reactor was naturally cooled, washed and dried under nitrogen protection, the ...

Embodiment 3

[0043] The semi-coke from Yulin in northern Shaanxi is used as the raw material for catalyst preparation, which is crushed and sieved into particles of 180-300 μm. According to the mass ratio of 1:10, weigh the semi-coke particles and Na 2 CO 3 (Analytical pure), after 0.25h of mechanical mixing by ball mill stirring and grinding, a mixture was formed.

[0044] Then, take the above-mentioned mixture that is 5g in quality and use it as a catalyst for catalyzing the cracking reaction of ethane, and react in a traditional fixed-bed reactor. The reaction space velocity is 10L / (h g cat ). Collect the gas generated by the ethane cracking reaction to obtain hydrogen-rich gas; under this condition, within 3 hours of reaction, the conversion rate of ethane is 96% to 99%, and the hydrogen gas fraction in the reaction gas is 88.2% to 91.0% ; After the reaction residue in the reactor is naturally cooled, washed and dried under the protection of nitrogen successively, the thick sample ...

technical field

[0001] The invention belongs to the field of conversion and utilization of low-carbon hydrocarbons, in particular to a method for preparing carbon fibers and hydrogen by catalytic cracking of low-carbon hydrocarbons. Background technique

[0002] The catalytic methane cracking hydrogen production process has a simple process, the products are only gaseous hydrogen and solid carbon, the products are easy to separate, and there is no CO or CO 2 It is a hydrogen production process with broad prospects. Compared with the current industrialized methane steam reforming hydrogen production process, the catalytic methane cracking hydrogen production process reduces the water-gas shift and CO 2 The processing steps simplify the process flow; and no high pressure is required, and the requirements for equipment are relatively low. At the same time, the carbon deposits (such as carbon fibers, carbon nanotubes, etc.) generated by it have broad market prospects, thereby ...

Examples

Embodiment 1

[0034] Get semi-coke from Yulin, northern Shaanxi (the bulk semi-coke of Wuzhou Coal Chemical Co., Ltd., Shenmu County, see Table 1 for industrial analysis and elemental analysis, it belongs to a kind of low-temperature pyrolysis semi-coke in coal, the same below) as the raw material for catalyst preparation , crushed and sieved into particles of 70-150 μm. According to the mass ratio of 1:1, weigh the semi-coke particles and Na 2 CO 3 (analytical pure), and simultaneously added to the water-ethanol binary solution (the volume ratio of water and ethanol is 5:1), stirred and mixed for 10 h, and then vacuum-dried to form a mixture.

[0035] Then, take the above-mentioned mixture that is 5g in quality and use it as a catalyst for catalytic methane cracking reaction, and react in a traditional fixed-bed reactor. 300L / (h·g cat ). Collect the gas generated by methane cracking reaction to obtain hydrogen-rich gas; under this condition, within 10 hours of reaction, the methane con...

Embodiment 2

[0040] The semi-coke from Yulin in northern Shaanxi is used as the raw material for catalyst preparation, which is crushed and sieved into particles of 180-300 μm. According to the mass ratio of 1:5, weigh the semi-coke particles and K 2 CO 3 (analytical pure), and simultaneously added to the water-ethanol binary solution (the volume ratio of water and ethanol is 5:1), stirred and mixed for 10 h, and then vacuum-dried to form a mixture.

[0041] Then, take the above-mentioned mixture that is 5g and use it as a catalyst for catalytic methane cracking reaction, and react in a traditional fixed-bed reactor. 100L / (h·g cat ). Collect the gas generated by methane cracking reaction to obtain hydrogen-rich gas; under this condition, within 5 hours of reaction, the methane conversion rate is 88% to 93%, and the hydrogen gas fraction in the reaction gas is 90.3% to 94.7%; After the reaction residue in the reactor was naturally cooled, washed and dried under nitrogen protection, the ...

Embodiment 3

[0043] The semi-coke from Yulin in northern Shaanxi is used as the raw material for catalyst preparation, which is crushed and sieved into particles of 180-300 μm. According to the mass ratio of 1:10, weigh the semi-coke particles and Na 2 CO 3 (Analytical pure), after 0.25h of mechanical mixing by ball mill stirring and grinding, a mixture was formed.

[0044] Then, take the above-mentioned mixture that is 5g in quality and use it as a catalyst for catalyzing the cracking reaction of ethane, and react in a traditional fixed-bed reactor. The reaction space velocity is 10L / (h g cat ). Collect the gas generated by the ethane cracking reaction to obtain hydrogen-rich gas; under this condition, within 3 hours of reaction, the conversion rate of ethane is 96% to 99%, and the hydrogen gas fraction in the reaction gas is 88.2% to 91.0% ; After the reaction residue in the reactor is naturally cooled, washed and dried under the protection of nitrogen successively, the thick sample ...

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