Disclosure of Invention
In order to overcome the defects in the prior art, the invention provides the synthesis gas methanation catalyst and the preparation method thereof, the catalyst takes Al modified petroleum coke-based active carbon as a carrier, overcomes the problem of high-temperature aggregation of active metal of the active carbon carrier catalyst, and has the advantages of good dispersion of active components, sintering resistance, high activity, difficult carbon deposition and the like.
The invention provides a synthesis gas methanation catalyst, which comprises an active component, an auxiliary agent and a carrier, wherein the active component is selected from Ni or Co, and is preferably Ni; the auxiliary agent is selected from one or more of alkaline earth metal, rare earth metal and IVB subgroup metal, preferably one or more of Ca, Mg, Zr, La and Ce; the carrier is Al modified petroleum coke-based activated carbon.
According to the synthesis gas methanation catalyst, the mass content of active components is 5-30 wt%, preferably 10-20 wt% calculated by elements; the mass content of the auxiliary agent is 1wt% -10 wt%, preferably 2wt% -4 wt% calculated by element; calculated by element, the mass content of Al is 1wt% -10 wt%, preferably 2wt% -4 wt%; the carrier content is 40wt% to 85wt%, preferably 60wt% to 80 wt%.
The specific surface of the synthetic gas methanation catalyst is 500-1500 m2Preferably 600 to 1000 m/g2(ii)/g; the pore size distribution is such that the pores smaller than 2nm are larger than 60%, preferably larger than 80%.
In the synthesis gas methanation catalyst, active components are combined with amorphous defects of active carbon embedded in petroleum coke-based and alumina in an active carbon graphite microchip layer, and the size of active metal crystal grains is 0.5-5 nm, preferably 1-3 nm.
The second aspect of the invention provides a preparation method of a synthesis gas methanation catalyst, which comprises the following steps:
(1) mixing petroleum coke, metaaluminate and an activating agent, and activating after uniformly mixing;
(2) washing and carrying out solid-liquid separation on the sample obtained in the step (1) until the filtrate is neutral;
(3) mixing the solid sample obtained by solid-liquid separation in the step (2) with water for low-temperature treatment, standing for solid-liquid separation, and drying and roasting the solid sample obtained by separation;
(4) and (4) introducing active metal and an auxiliary agent into the sample obtained in the step (3), and then drying and roasting to obtain the synthesis gas methanation catalyst.
In the preparation method of the synthesis gas methanation catalyst, the metaaluminate in the step (1) is one or more of potassium metaaluminate, sodium metaaluminate and lithium metaaluminate, and preferably potassium metaaluminate.
In the preparation method of the synthesis gas methanation catalyst, the activating agent in the step (1) is one or more of potassium hydroxide, sodium hydroxide, potassium bicarbonate and sodium bicarbonate, and potassium hydroxide is preferred.
In the preparation method of the synthesis gas methanation catalyst, in the step (1), the mass ratio of petroleum coke, metaaluminate (calculated by the mass of Al element) and an activating agent is 1: 0.005-0.05: 1-5, preferably 1: 0.01-0.02: 2 to 4.
In the preparation method of the synthesis gas methanation catalyst, the activation process in the step (1) is as follows: grinding petroleum coke into powder, then uniformly mixing the powder with metaaluminate and an activating agent, heating to an activation temperature, cooling to room temperature after activation is completed, and performing subsequent treatment, wherein the activation temperature is 600-1000 ℃, preferably 700-900 ℃, and the activation time is 5-240 min, preferably 10-120 min. The activation process is further preferably carried out under microwave irradiation conditions, the microwave frequency being 2450MHz or 915 MHz; the microwave power is 1-10 kw per kg of petroleum coke, and preferably 2-4 kw. When the activation is carried out under the microwave radiation condition, the activation is further preferably carried out in two sections, the first section is activated for 10-60 min at 400-600 ℃ under the vacuum condition, inert gas or nitrogen is introduced to the atmosphere under the constant temperature condition, and the temperature is continuously increased to 700-900 ℃ under the microwave radiation condition for activation for 10-30 min.
In the preparation method of the synthesis gas methanation catalyst, the washing in the step (2) is washing with water, the washing temperature is 50-95 ℃, and preferably 70-90 ℃, and the specific operation can be that firstly, the solid sample obtained in the step (1) is heated and washed at the washing temperature, then, the solid sample is mixed with water at the same temperature, and after uniform mixing, solid-liquid separation is carried out until the filtrate is neutral.
In the preparation method of the synthesis gas methanation catalyst, the low-temperature treatment temperature in the step (3) is 1-20 ℃, preferably 5-10 ℃, the mixture is uniformly mixed and then placed for 2-16 hours, preferably 4-8 hours, and then solid-liquid separation is carried out.
In the preparation method of the synthesis gas methanation catalyst, the drying temperature in the step (3) is 80-200 ℃, the drying time is 2-10 hours, the preferable drying temperature is 120-180 ℃, and the drying time is 4-8 hours. The drying is preferably carried out under vacuum.
In the preparation method of the synthesis gas methanation catalyst, the roasting in the step (3) is carried out in an inert atmosphere or a nitrogen atmosphere, the roasting temperature is 500-700 ℃, the preferred roasting temperature is 540-650 ℃, the roasting time is 2-10 hours, and the preferred roasting time is 4-8 hours.
In the preparation method of the synthesis gas methanation catalyst, the sample obtained in the step (3) can be further molded according to a method generally used in the field, such as extrusion, tabletting and the like, and can be prepared or selected into a proper particle form according to the use requirement, such as strip, tablet and the like.
In the preparation method of the synthesis gas methanation catalyst, the method for introducing the active metal and the auxiliary agent into the sample obtained in the step (3) in the step (4) is carried out by a method known in the art, and the solid obtained in the step (4) is impregnated by using a soluble salt solution containing the active metal and a soluble salt solution containing the auxiliary agent, and the method comprises an equal-volume impregnation method, a supersaturated impregnation method and a kneading method, and preferably an equal-volume impregnation method; when the active metal and the auxiliary are introduced, they may be introduced simultaneously or in multiple portions.
In the preparation method of the synthesis gas methanation catalyst, the soluble salt containing the active metal in the step (4) can be one or more of nitrate, sulfate and hydrochloride, and preferably nitrate.
In the preparation method of the synthesis gas methanation catalyst, the soluble salt containing the auxiliary agent in the step (4) can be one or more of nitrate, sulfate and hydrochloride, and is preferably nitrate.
In the preparation method of the synthesis gas methanation catalyst, the drying temperature in the step (4) is 60-160 ℃, the preferred drying temperature is 80-120 ℃, the drying time is 2-10 hours, and the preferred drying time is 4-8 hours. The drying is preferably carried out under vacuum.
In the preparation method of the synthesis gas methanation catalyst, the roasting in the step (4) is carried out in an inert atmosphere or a nitrogen atmosphere, the roasting temperature is 500-700 ℃, the preferred roasting temperature is 540-650 ℃, the roasting time is 2-10 hours, and the preferred roasting time is 4-8 hours.
The synthesis gas methanation catalyst prepared by the method is applied to the reaction of preparing natural gas by methanation of synthesis gas.
Compared with the prior art, the synthesis gas methanation catalyst and the preparation method thereof have the following advantages:
1. the synthesis gas methanation catalyst provided by the invention has the advantages of large specific surface area, good dispersion of active metal, high reaction activity, sintering resistance, difficult carbon deposition and the like, and the preparation method is simple.
2. According to the preparation method of the catalyst, Al is introduced in the petroleum coke activation process, an activating agent enters a diffusion path generated by petroleum coke bulk phase, and is combined with amorphous carbon defects and graphite carbon sheet layers to form aluminum carbide under the action of microwave catalysis, and the activated carbon/alumina composite carrier is formed through low-temperature hydrolysis. The loaded active metal is combined with the amorphous defect of the petroleum coke-based active carbon and the alumina embedded in the active carbon graphite microchip layer to obtain the catalyst with high dispersion and high temperature stability, and the problems that the active metal is aggregated and loses activity due to dehydration and condensation of oxygen-containing groups at high temperature when the metal catalyst taking the active carbon as a carrier is applied to high-temperature reaction are solved.
3. According to the preparation method of the catalyst, unreacted activating agents are removed through high-temperature water washing, the elution rate of the unreacted activating agents is increased, hydrolysis of carbides is inhibited, and then aluminum carbide is fully hydrolyzed under the low-temperature condition to form the activated carbon/alumina composite carrier.
4. The catalyst takes the Al modified activated carbon as a carrier, and improves the carbon deposition resistance of the catalyst by utilizing the intermiscibility of the activated carbon carrier and carbon deposition generated in the application process and abundant micropores.
5. According to the preparation method of the catalyst, the modification metal introduced in the petroleum coke activation process takes aluminate as a precursor, and can more easily enter the petroleum coke-based activated carbon. The reason is that under the action of the activator, active sites of the petroleum coke react to generate positive charged cavities, and aluminate anions are more easily combined and intercalated.
Detailed Description
The technical contents and effects of the present invention will be further described with reference to examples, but the present invention is not limited thereto.
In the following examples and comparative examples, low-temperature N was used for the specific surface area and pore size distribution of the catalyst2Measuring by an adsorption method; the grain size of the active component of the catalyst is measured by an X-ray broadening method; catalyst composition was determined using XRF analysis techniques.
Example 1
Grinding 100g of petroleum coke into powder, uniformly mixing with 5.06g of potassium metaaluminate and 200g of potassium hydroxide, placing in a microwave heating furnace with microwave frequency of 2450MHz, vacuumizing, heating to 500 ℃ under the condition of microwave power of 0.2kw, keeping the temperature constant for 40min, introducing nitrogen to normal pressure, and continuously heating to 800 ℃ under the condition of microwave power of 0.2kw for activation for 20 min. And after the activation is finished, cooling to normal temperature, taking out the obtained sample, placing the sample in a drying box, heating to 80 ℃, then mixing the sample with deionized water at the same temperature, uniformly stirring, carrying out solid-liquid separation, and repeating for several times until the filtrate is neutral. And (3) placing the solid sample obtained after solid-liquid separation into deionized water at 5 ℃, uniformly mixing, keeping the system at 5 ℃ and standing for 4h, then carrying out solid-liquid separation, drying the solid sample obtained after separation at 150 ℃ for 6h under a vacuum condition, and roasting at 600 ℃ for 6h under a nitrogen atmosphere to obtain the Al modified activated carbon carrier.
Weighing 20g of Al modified activated carbon carrier, weighing a proper amount of nickel nitrate hexahydrate and zirconium nitrate pentahydrate according to the Ni content of the final catalyst and the Zr content of 4%, dissolving in a proper amount of deionized water, fixing the volume to 26mL, loading the Al modified activated carbon carrier by adopting an isometric impregnation method, stirring uniformly, and aging for 2 h; and then placing the sample in a vacuum drying oven, drying for 6h at 100 ℃ under a vacuum condition, and roasting for 6h at 600 ℃ under a nitrogen atmosphere to obtain the catalyst with the mass percentage contents of 10% of Ni, 4% of Zr and 2% of Al in terms of elements, wherein the mass percentage content is marked as C-1.
Example 2
Grinding 100g of petroleum coke into powder, uniformly mixing with 6.77g of potassium metaaluminate and 300g of potassium hydroxide, placing in a microwave heating furnace with microwave frequency of 2450MHz, vacuumizing, heating to 400 ℃ under the condition of microwave power of 0.3kw, keeping the temperature constant for 60min, introducing nitrogen to the normal pressure, and continuously heating to 700 ℃ under the condition of microwave power of 0.3kw for activation for 30 min. And after the activation is finished, cooling to normal temperature, taking out the obtained sample, placing the sample in a drying box, heating to 80 ℃, then mixing the sample with deionized water at the same temperature, uniformly stirring, carrying out solid-liquid separation, and repeating for several times until the filtrate is neutral. And (3) placing the solid sample obtained after solid-liquid separation into deionized water at 8 ℃, uniformly mixing, keeping the system at 8 ℃ and standing for 6h, then carrying out solid-liquid separation, drying the solid sample obtained after separation at 120 ℃ for 8h under a vacuum condition, and roasting at 540 ℃ for 8h under a nitrogen atmosphere to obtain the Al modified activated carbon carrier.
Weighing 20g of Al modified activated carbon carrier, weighing a proper amount of nickel nitrate hexahydrate and zirconium nitrate pentahydrate according to the Ni content of the final catalyst and the Zr content of 3%, dissolving in a proper amount of deionized water, fixing the volume to 26mL, loading the Al modified activated carbon carrier by adopting an isometric impregnation method, stirring uniformly, and aging for 2 h; and then placing the sample in a vacuum drying oven, drying for 6h at 100 ℃ under a vacuum condition, and roasting for 6h at 600 ℃ under a nitrogen atmosphere to obtain the catalyst with the mass percent of 15 percent of Ni, 3 percent of Zr and 3 percent of Al in terms of elements, wherein the mass percent of the catalyst is marked as C-2.
Example 3
Grinding 100g of petroleum coke into powder, uniformly mixing with 9.94g of potassium metaaluminate and 300g of potassium hydroxide, placing in a microwave heating furnace with microwave frequency of 2450MHz, vacuumizing, heating to 600 ℃ under the condition of microwave power of 0.4kw, keeping the temperature constant for 10min, introducing nitrogen to the normal pressure, and continuously heating to 900 ℃ under the condition of microwave power of 0.4kw for activation for 10 min. And after the activation is finished, cooling to normal temperature, taking out the obtained sample, placing the sample in a drying box, heating to 90 ℃, then mixing the sample with deionized water at the same temperature, uniformly stirring, carrying out solid-liquid separation, and repeating for several times until the filtrate is neutral. And (3) placing the solid sample obtained after solid-liquid separation into deionized water at 10 ℃, uniformly mixing, keeping the system at 10 ℃ and standing for 8h, then carrying out solid-liquid separation, drying the solid sample obtained after separation at 180 ℃ for 4h under a vacuum condition, and roasting at 650 ℃ for 4h under a nitrogen atmosphere to obtain the Al modified activated carbon carrier.
Weighing 20g of Al modified activated carbon carrier, weighing a proper amount of nickel nitrate hexahydrate and zirconium nitrate pentahydrate according to the Ni content of the final catalyst and the Zr content of 2%, dissolving in a proper amount of deionized water, fixing the volume to 26mL, loading the Al modified activated carbon carrier by adopting an isometric impregnation method, stirring uniformly, and aging for 2 h; and then placing the sample in a vacuum drying oven, drying the sample for 8 hours at 80 ℃ under a vacuum condition, and roasting the sample for 8 hours at 540 ℃ under a nitrogen atmosphere to obtain the catalyst which comprises the following components in percentage by mass of 20% of Ni, 2% of Zr and 4% of Al, and marking the catalyst as C-3.
Example 4
Grinding 100g of petroleum coke into powder, uniformly mixing with 6.77g of potassium metaaluminate and 300g of potassium hydroxide, placing in a microwave heating furnace with microwave frequency of 2450MHz, vacuumizing, heating to 400 ℃ under the condition of microwave power of 0.3kw, keeping the temperature constant for 60min, introducing nitrogen to the normal pressure, and continuously heating to 700 ℃ under the condition of microwave power of 0.3kw for activation for 30 min. And after the activation is finished, cooling to normal temperature, taking out the obtained sample, placing the sample in a drying box, heating to 80 ℃, then mixing the sample with deionized water at the same temperature, uniformly stirring, carrying out solid-liquid separation, and repeating for several times until the filtrate is neutral. And (3) placing the solid sample obtained after solid-liquid separation into deionized water at 5 ℃, uniformly mixing, keeping the system at 5 ℃ and standing for 4h, then carrying out solid-liquid separation, drying the solid sample obtained after separation at 150 ℃ for 6h under a vacuum condition, and roasting at 600 ℃ for 6h under a nitrogen atmosphere to obtain the Al modified activated carbon carrier.
Weighing 20g of Al modified activated carbon carrier, weighing a proper amount of nickel nitrate hexahydrate and zirconium nitrate pentahydrate according to the content of Co and the content of Zr of the final catalyst of 15 percent and 3 percent, dissolving the nickel nitrate hexahydrate and the zirconium nitrate pentahydrate in a proper amount of deionized water, fixing the volume to 26mL, loading the Al modified activated carbon carrier by adopting an isometric impregnation method, stirring uniformly, and aging for 2 hours; and then placing the sample in a vacuum drying oven, drying for 6h at 100 ℃ under a vacuum condition, and roasting for 6h at 600 ℃ under a nitrogen atmosphere to obtain the catalyst with the mass percentage of the elements of 15 percent of Co, 3 percent of Zr and 3 percent of Al, and marking as C-4.
Example 5
Grinding 100g of petroleum coke into powder, uniformly mixing with 5.22g of potassium metaaluminate and 400g of potassium hydroxide, placing in a microwave heating furnace with microwave frequency of 2450MHz, vacuumizing, heating to 500 ℃ under the condition of microwave power of 0.4kw, keeping the temperature constant for 40min, introducing nitrogen to normal pressure, and continuously heating to 800 ℃ under the condition of microwave power of 0.4kw for activation for 20 min. And after the activation is finished, cooling to normal temperature, taking out the obtained sample, placing the sample in a drying box, heating to 80 ℃, then mixing the sample with deionized water at the same temperature, uniformly stirring, carrying out solid-liquid separation, and repeating for several times until the filtrate is neutral. And (3) placing the solid sample obtained after solid-liquid separation into deionized water at 5 ℃, uniformly mixing, keeping the system at 5 ℃ and standing for 4h, then carrying out solid-liquid separation, drying the solid sample obtained after separation at 150 ℃ for 6h under a vacuum condition, and roasting at 600 ℃ for 6h under a nitrogen atmosphere to obtain the Al modified activated carbon carrier.
Weighing 20g of Al modified activated carbon carrier, weighing a proper amount of nickel nitrate hexahydrate and lanthanum nitrate hexahydrate according to the Ni content of the final catalyst and the La content of 3%, dissolving in a proper amount of deionized water, fixing the volume to 26mL, loading the Al modified activated carbon carrier by adopting an isometric impregnation method, stirring uniformly, and aging for 2 h; and then placing the sample in a vacuum drying oven, drying at 120 ℃ for 4h under a vacuum condition, and roasting at 600 ℃ for 6h under a nitrogen atmosphere to obtain the catalyst with the mass percent of 15 percent of Ni, 3 percent of La and 3 percent of Al in terms of elements, wherein the mass percent of the catalyst is marked as C-5.
Example 6
Grinding 100g of petroleum coke into powder, uniformly mixing with 6.92g of potassium metaaluminate and 300g of potassium hydroxide, placing in a microwave heating furnace with microwave frequency of 2450MHz, vacuumizing, heating to 500 ℃ under the condition of microwave power of 0.3kw, keeping the temperature constant for 40min, introducing nitrogen to normal pressure, and continuously heating to 800 ℃ under the condition of microwave power of 0.3kw for activation for 20 min. And after the activation is finished, cooling to normal temperature, taking out the obtained sample, placing the sample in a drying box, heating to 80 ℃, then mixing the sample with deionized water at the same temperature, uniformly stirring, carrying out solid-liquid separation, and repeating for several times until the filtrate is neutral. And (3) placing the solid sample obtained after solid-liquid separation into deionized water at 5 ℃, uniformly mixing, keeping the system at 5 ℃ and standing for 4h, then carrying out solid-liquid separation, drying the solid sample obtained after separation at 150 ℃ for 6h under a vacuum condition, and roasting at 600 ℃ for 6h under a nitrogen atmosphere to obtain the Al modified activated carbon carrier.
Weighing 20g of Al modified activated carbon carrier, weighing a proper amount of cobalt nitrate hexahydrate and magnesium nitrate according to the content of Co and the content of Mg of the final catalyst of 15 percent and 3 percent, dissolving the cobalt nitrate hexahydrate and the magnesium nitrate into a proper amount of deionized water, fixing the volume to 26mL, loading the Al modified activated carbon carrier by adopting an isometric impregnation method, stirring uniformly, and aging for 2 hours; and then placing the sample in a vacuum drying oven, drying for 6h at 100 ℃ under a vacuum condition, and roasting for 6h at 600 ℃ under a nitrogen atmosphere to obtain the catalyst with the mass percentage of Co, Mg and Al accounting for 15%, 3% and 3% of the catalyst by element, and marking as C-6.
Example 7
Grinding 100g of petroleum coke into powder, uniformly mixing with 5.74g of potassium metaaluminate and 300g of potassium hydroxide, placing in a microwave heating furnace with microwave frequency of 2450MHz, vacuumizing, heating to 500 ℃ under the condition of microwave power of 0.3kw, keeping the temperature constant for 40min, introducing nitrogen to normal pressure, and continuously heating to 800 ℃ under the condition of microwave power of 0.3kw for activation for 20 min. And after the activation is finished, cooling to normal temperature, taking out the obtained sample, placing the sample in a drying box, heating to 80 ℃, then mixing the sample with deionized water at the same temperature, uniformly stirring, carrying out solid-liquid separation, and repeating for several times until the filtrate is neutral. And (3) placing the solid sample obtained after solid-liquid separation into deionized water at the temperature of 8 ℃, uniformly mixing, keeping the system at the temperature of 8 ℃ and standing for 6h, then carrying out solid-liquid separation, drying the solid sample obtained after separation at the temperature of 150 ℃ for 6h under a vacuum condition, and roasting at the temperature of 600 ℃ for 6h under a nitrogen atmosphere to obtain the Al modified activated carbon carrier.
Weighing 20g of Al modified activated carbon carrier, weighing a proper amount of nickel nitrate hexahydrate and zirconium nitrate pentahydrate according to the Ni content of the final catalyst of 5% and the Zr content of 3%, dissolving in a proper amount of deionized water, fixing the volume to 26mL, loading the Al modified activated carbon carrier by adopting an isometric impregnation method, stirring uniformly, and aging for 2 h; and then placing the sample in a vacuum drying oven, drying for 6h at 100 ℃ under a vacuum condition, and roasting for 6h at 600 ℃ under a nitrogen atmosphere to obtain the catalyst with the mass percentage of 5% of Ni, 3% of Zr and 3% of Al in terms of elements, wherein the mass percentage is marked as C-7.
Example 8
Grinding 100g of petroleum coke into powder, uniformly mixing with 9.27g of potassium metaaluminate and 300g of potassium hydroxide, placing in a microwave heating furnace with microwave frequency of 2450MHz, vacuumizing, heating to 500 ℃ under the condition of microwave power of 0.3kw, keeping the temperature constant for 40min, introducing nitrogen to normal pressure, and continuously heating to 800 ℃ under the condition of microwave power of 0.3kw for activation for 20 min. And after the activation is finished, cooling to normal temperature, taking out the obtained sample, placing the sample in a drying box, heating to 80 ℃, then mixing the sample with deionized water at the same temperature, uniformly stirring, carrying out solid-liquid separation, and repeating for several times until the filtrate is neutral. And (3) placing the solid sample obtained after solid-liquid separation into deionized water at 5 ℃, uniformly mixing, keeping the system at 1 ℃ and standing for 2h, then carrying out solid-liquid separation, drying the solid sample obtained after separation at 150 ℃ for 6h under a vacuum condition, and roasting at 600 ℃ for 6h under a nitrogen atmosphere to obtain the Al modified activated carbon carrier.
Weighing 20g of Al modified activated carbon carrier, weighing a proper amount of nickel nitrate hexahydrate and zirconium nitrate pentahydrate according to the Ni content of the final catalyst and the Zr content of 3%, dissolving in a proper amount of deionized water, fixing the volume to 26mL, loading the Al modified activated carbon carrier by adopting an isometric impregnation method, stirring uniformly, and aging for 2 h; and then placing the sample in a vacuum drying oven, drying for 6h at 100 ℃ under a vacuum condition, and roasting for 6h at 600 ℃ under a nitrogen atmosphere to obtain the catalyst with the mass percentage contents of 30% of Ni, 3% of Zr and 3% of Al in terms of elements, wherein the mass percentage content is marked as C-8.
Example 9
Grinding 100g of petroleum coke into powder, then uniformly mixing with 2.07g of sodium metaaluminate and 300g of sodium hydroxide, placing in a microwave heating furnace with microwave frequency of 2450MHz, vacuumizing, heating to 600 ℃ under the condition of microwave power of 1kw, keeping the temperature constant for 10min, then introducing nitrogen to normal pressure, and continuously heating to 900 ℃ under the condition of microwave power of 1kw for activation for 10 min. And after the activation is finished, cooling to normal temperature, taking out the obtained sample, placing the sample in a drying box, heating to 80 ℃, then mixing the sample with deionized water at the same temperature, uniformly stirring, carrying out solid-liquid separation, and repeating for several times until the filtrate is neutral. And (3) placing the solid sample obtained after solid-liquid separation into deionized water at 5 ℃, uniformly mixing, keeping the system at 5 ℃ and standing for 4h, then carrying out solid-liquid separation, drying the solid sample obtained after separation at 150 ℃ for 6h under a vacuum condition, and roasting at 600 ℃ for 6h under a nitrogen atmosphere to obtain the Al modified activated carbon carrier.
Weighing 20g of Al modified activated carbon carrier, weighing a proper amount of nickel nitrate hexahydrate and zirconium nitrate pentahydrate according to the Ni content of the final catalyst and the Zr content of 10%, dissolving in a proper amount of deionized water, fixing the volume to 26mL, loading the Al modified activated carbon carrier by adopting an isometric impregnation method, stirring uniformly, and aging for 2 h; and then placing the sample in a vacuum drying oven, drying for 6h at 100 ℃ under a vacuum condition, and roasting for 6h at 600 ℃ under a nitrogen atmosphere to obtain the catalyst with the mass percent of 15 percent of Ni, 10 percent of Zr and 1 percent of Al in terms of elements, wherein the mass percent of the catalyst is marked as C-9.
Example 10
Grinding 100g of petroleum coke into powder, uniformly mixing with 18.38g of potassium metaaluminate and 500g of potassium hydroxide, placing in a microwave heating furnace with microwave frequency of 2450MHz, vacuumizing, heating to 500 ℃ under the condition of microwave power of 0.3kw, keeping the temperature constant for 40min, introducing nitrogen to normal pressure, and continuously heating to 800 ℃ under the condition of microwave power of 0.3kw for activation for 20 min. And after the activation is finished, cooling to normal temperature, taking out the obtained sample, placing the sample in a drying box, heating to 80 ℃, then mixing the sample with deionized water at the same temperature, uniformly stirring, carrying out solid-liquid separation, and repeating for several times until the filtrate is neutral. And (3) placing the solid sample obtained after solid-liquid separation into deionized water at 5 ℃, uniformly mixing, keeping the system at 5 ℃ and standing for 4h, then carrying out solid-liquid separation, drying the solid sample obtained after separation at 150 ℃ for 6h under a vacuum condition, and roasting at 600 ℃ for 6h under a nitrogen atmosphere to obtain the Al modified activated carbon carrier.
Weighing 20g of Al modified activated carbon carrier, weighing a proper amount of nickel chloride hexahydrate and zirconium chloride according to the Ni content of the final catalyst and the Zr content of 1%, dissolving in a proper amount of deionized water, fixing the volume to 26mL, loading the Al modified activated carbon carrier by adopting an isometric impregnation method, stirring uniformly, and aging for 2 h; and then placing the sample in a vacuum drying oven, drying for 6h at 100 ℃ under a vacuum condition, and roasting for 6h at 600 ℃ under a nitrogen atmosphere to obtain the catalyst with the mass percent of 15 percent of Ni, 1 percent of Zr and 10 percent of Al in terms of elements, wherein the mass percent of the catalyst is marked as C-10.
Example 11
Grinding 100g of petroleum coke into powder, uniformly mixing with 6.02g of potassium metaaluminate and 300g of potassium hydroxide, placing in a microwave heating furnace with the microwave frequency of 2450MHz, vacuumizing, heating to 800 ℃ under the condition that the microwave power is 0.3kw, and keeping the temperature constant for 60 min. And after the activation is finished, cooling to normal temperature, taking out the obtained sample, placing the sample in a drying box, heating to 80 ℃, then mixing the sample with deionized water at the same temperature, uniformly stirring, carrying out solid-liquid separation, and repeating for several times until the filtrate is neutral. And (3) placing the solid sample obtained after solid-liquid separation into deionized water at 5 ℃, uniformly mixing, keeping the system at 5 ℃ and standing for 4h, then carrying out solid-liquid separation, drying the solid sample obtained after separation at 150 ℃ for 6h under a vacuum condition, and roasting at 600 ℃ for 6h under a nitrogen atmosphere to obtain the Al modified activated carbon carrier.
Weighing 20g of Al modified activated carbon carrier, weighing a proper amount of nickel nitrate hexahydrate and zirconium nitrate pentahydrate according to the Ni content of the final catalyst and the Zr content of 3%, dissolving in a proper amount of deionized water, fixing the volume to 26mL, loading the Al modified activated carbon carrier by adopting an isometric impregnation method, stirring uniformly, and aging for 2 h; and then placing the sample in a vacuum drying oven, drying for 6h at 100 ℃ under a vacuum condition, and roasting for 6h at 600 ℃ under a nitrogen atmosphere to obtain the catalyst with the mass percent of 15 percent of Ni, 3 percent of Zr and 3 percent of Al in terms of elements, wherein the mass percent of the catalyst is marked as C-11.
Example 12
Grinding 100g of petroleum coke into powder, then uniformly mixing with 7.53g of potassium metaaluminate and 200g of potassium hydroxide, placing in a high-temperature vacuum roasting furnace, heating to 800 ℃ under a vacuum condition, and activating for 60 min. And after the activation is finished, cooling to normal temperature, taking out the obtained sample, placing the sample in a drying box, heating to 80 ℃, then mixing the sample with deionized water at the same temperature, uniformly stirring, carrying out solid-liquid separation, and repeating for several times until the filtrate is neutral. And (3) placing the solid sample obtained after solid-liquid separation into deionized water at 5 ℃, uniformly mixing, keeping the system at 5 ℃ and standing for 4h, then carrying out solid-liquid separation, drying the solid sample obtained after separation at 150 ℃ for 6h under a vacuum condition, and roasting at 600 ℃ for 6h under a nitrogen atmosphere to obtain the Al modified activated carbon carrier.
Weighing 20g of Al modified activated carbon carrier, weighing a proper amount of nickel nitrate hexahydrate and zirconium nitrate pentahydrate according to the Ni content of the final catalyst and the Zr content of 3%, dissolving in a proper amount of deionized water, fixing the volume to 26mL, loading the Al modified activated carbon carrier by adopting an isometric impregnation method, stirring uniformly, and aging for 2 h; and then placing the sample in a vacuum drying oven, drying for 6h at 100 ℃ under a vacuum condition, and roasting for 6h at 600 ℃ under a nitrogen atmosphere to obtain the catalyst with the mass percent of 15 percent of Ni, 3 percent of Zr and 3 percent of Al in terms of elements, wherein the mass percent of the catalyst is marked as C-12.
Comparative example 1
Grinding 100g of petroleum coke into powder, then uniformly mixing the powder with 300g of potassium hydroxide, placing the mixture in a microwave heating furnace with microwave frequency of 2450MHz, vacuumizing, heating to 500 ℃ under the condition that the microwave power is 0.3kw, keeping the temperature constant for 40min, then introducing nitrogen to the normal pressure, and continuously heating to 800 ℃ under the condition that the microwave power is 0.3kw to activate for 20 min.
Grinding the activated sample into powder, weighing, and mixing the powder according to a mass ratio of 1: 15, adding the mixture into an acetic acid solution with the concentration of 30wt%, fully stirring, then carrying out solid-liquid separation, washing the obtained solid by deionized water until the pH value of the filtrate is neutral, placing the obtained fixed sample in a vacuum drying oven, and drying for 6 hours at 150 ℃ under the vacuum condition.
Weighing 20g of the activated carbon carrier, weighing a proper amount of nickel nitrate hexahydrate, zirconium nitrate pentahydrate and aluminum nitrate nonahydrate according to the Ni content of 15%, the Zr content of 3% and the Al content of 3% of the final catalyst, dissolving in a proper amount of deionized water, fixing the volume to 26mL, loading on the activated carbon carrier by adopting an isometric impregnation method, stirring uniformly, and aging for 2 h; and then placing the sample in a vacuum drying oven, drying for 6h at 100 ℃ under a vacuum condition, and roasting for 6h at 600 ℃ under a nitrogen atmosphere to obtain the catalyst with the mass percent of 15 percent of Ni, 3 percent of Zr and 3 percent of Al in terms of elements, wherein the mass percent of the catalyst is marked as D-1.
Evaluation of catalyst reaction Performance: the reaction performance was examined with samples of the catalysts prepared in examples 1 to 12 and comparative example 1, respectively, and the reaction was carried out in a continuous flow fixed bed reactor with a catalyst loading of 3g, H2The reaction temperature is 300 ℃, the reaction pressure is 2MPa, and the volume space velocity is 8000h-1(ii) a The product was analyzed on-line by gas chromatography and the results are shown in Table 1.
TABLE 1 catalyst Properties and reaction Performance