CN114308107B - Graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst and preparation method and application thereof - Google Patents
Graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst and preparation method and application thereof Download PDFInfo
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- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 title claims abstract description 117
- 239000003054 catalyst Substances 0.000 title claims abstract description 81
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- 238000002360 preparation method Methods 0.000 title abstract description 7
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- KZEVSDGEBAJOTK-UHFFFAOYSA-N 1-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)-2-[5-[2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidin-5-yl]-1,3,4-oxadiazol-2-yl]ethanone Chemical compound N1N=NC=2CN(CCC=21)C(CC=1OC(=NN=1)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F)=O KZEVSDGEBAJOTK-UHFFFAOYSA-N 0.000 description 1
- HMUNWXXNJPVALC-UHFFFAOYSA-N 1-[4-[2-(2,3-dihydro-1H-inden-2-ylamino)pyrimidin-5-yl]piperazin-1-yl]-2-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)ethanone Chemical compound C1C(CC2=CC=CC=C12)NC1=NC=C(C=N1)N1CCN(CC1)C(CN1CC2=C(CC1)NN=N2)=O HMUNWXXNJPVALC-UHFFFAOYSA-N 0.000 description 1
- VZSRBBMJRBPUNF-UHFFFAOYSA-N 2-(2,3-dihydro-1H-inden-2-ylamino)-N-[3-oxo-3-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propyl]pyrimidine-5-carboxamide Chemical compound C1C(CC2=CC=CC=C12)NC1=NC=C(C=N1)C(=O)NCCC(N1CC2=C(CC1)NN=N2)=O VZSRBBMJRBPUNF-UHFFFAOYSA-N 0.000 description 1
- WZFUQSJFWNHZHM-UHFFFAOYSA-N 2-[4-[2-(2,3-dihydro-1H-inden-2-ylamino)pyrimidin-5-yl]piperazin-1-yl]-1-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)ethanone Chemical compound C1C(CC2=CC=CC=C12)NC1=NC=C(C=N1)N1CCN(CC1)CC(=O)N1CC2=C(CC1)NN=N2 WZFUQSJFWNHZHM-UHFFFAOYSA-N 0.000 description 1
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
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Abstract
The invention discloses a graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst which comprises the following components in parts by weight: 0.5 part of palladium element, 99.5 parts of graphene-based nitrogen-doped hierarchical pore carbon and 6-14 parts of nitrogen element, wherein the nitrogen element is doped in the graphene-based nitrogen-doped hierarchical pore carbon; the preparation method of the catalyst comprises the following steps: 1. preparing graphene-based nitrogen-doped phenolic resin by adopting a sol-gel method; 2. carbonizing to prepare graphene-based nitrogen-doped hierarchical pore carbon; 3. carrying out reduction after loading the palladium precursor; the invention also discloses application of the catalyst in hydrofining of crude terephthalic acid. The nitrogen doped with the catalyst carrier improves the surface chemical property, improves the dispersity of palladium and jointly improves the catalytic activity of the catalyst; the invention adopts a sol-gel method to combine carbonization and reduction, so as to solve the problems of low Pd utilization rate and poor catalyst activity in the catalyst; the catalyst has higher activity on hydrofining of crude terephthalic acid.
Description
Technical Field
The invention belongs to the technical field of catalysts, and particularly relates to a graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst, and a preparation method and application thereof.
Background
Refined terephthalic acid (PTA) is an important organic dibasic acid and is widely used for producing polyester fibers, polyester bottle chips and polyester films. A typical process for PTA industrial production is a two-step refined PTA process, wherein Paraxylene (PX) is used as a raw material, and crude terephthalic acid is prepared by oxidation under the action of a catalyst. Since crude terephthalic acid contains by-product 4-carboxybenzaldehyde (4-CBA), the product quality of PTA and the processing performance of subsequent polyester are affected, and the crude terephthalic acid needs to be removed by adopting a hydrofining step. The hydrofining reaction of PTA is to reduce 4-CBA in crude terephthalic acid into p-methylbenzoic acid which is easy to dissolve in water under the conditions of temperature 270-290 ℃ and pressure 7.0-8.0 MPa under the action of palladium-carbon catalyst, and then to prepare fiber-grade PTA through crystallization, separation and drying.
Palladium is the most widely used active component in crude terephthalic acid hydrofining, and the catalyst commonly used in industrial production is palladium catalyst supported by active carbon at present, but some challenges still exist. On the one hand, activated carbon is unfavorable for the diffusion of molecules due to its huge microporous structure. Therefore, the porous structure of the carbon material must be carefully designed to enhance mass transfer to improve catalytic efficiency. On the other hand, due to the weak interactions with metals of activated carbon, which are chemically inert at their surfaces, active metal species exhibit a greater tendency to aggregate and leach out on the activated carbon, resulting in loss and agglomeration of active metal particles, and researchers have attempted to modify the support to enhance such interactions.
The Chinese patent publication No. CN104549239A discloses a catalyst with graphene as a carrier, wherein the catalyst carrier is obtained by reducing graphene oxide, the reduction of a palladium-containing compound and the reduction of the graphene oxide are simultaneously carried out by adopting a reducing agent microwave method, and the catalyst has good hydrogenation activity on 4-CBA, but the specific surface area of the adopted graphene carrier is lower, and only 300m 2 And/g, the active surface after loading is smaller.
Chinese patent publication No. CN112237946a discloses a palladium catalyst supported on nitrogen-doped activated carbon, the catalyst comprising the following components: 0.1-2 parts of palladium element, 98-100 parts of active carbon and 1-6 parts of nitrogen element. The palladium-carbon catalyst carried by the nitrogen-doped active carbon has high palladium dispersity, and the hydrogenation efficiency is obviously improved compared with that of common palladium-carbon when the catalyst is used in the hydrofining reaction of crude terephthalic acid. However, the carrier nitrogen content is only 6%, and the effect of nitrogen doping is not fully exerted.
Disclosure of Invention
The technical problem to be solved by the invention is to provide the graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst aiming at the defects in the prior art. The nitrogen doped by the carrier in the graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst improves the surface chemical property of the carrier, improves the dispersity of active component metal palladium, and the hierarchical pore structure improves the mass transfer performance of the carrier, so that the catalytic activity of the catalyst relative to commercial Pd/C is improved together.
In order to solve the technical problems, the invention adopts the following technical scheme: the graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst is characterized by comprising the following components in parts by weight: 0.5 part of palladium element, 99.5 parts of graphene-based nitrogen-doped hierarchical pore carbon and 6-14 parts of nitrogen element, wherein the nitrogen element is doped in the graphene-based nitrogen-doped hierarchical pore carbon.
The carrier in the graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst is graphene-based nitrogen-doped hierarchical pore carbon, the doped nitrogen improves the surface chemical property of the carrier, the dispersity of active component metal palladium is improved, the hierarchical pore structure of the catalyst improves the mass transfer performance of the carrier, and the catalytic activity of the catalyst relative to commercial Pd/C is jointly improved.
The graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst is characterized in that the dispersity of palladium element in the catalyst is 33% -55%. The dispersity of palladium element in the catalyst is higher than that of palladium element in commercial Pd/C catalyst by 23.9%, so that the catalyst has higher catalytic activity.
In addition, the invention also discloses a method for preparing the graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst, which is characterized by comprising the following steps of:
step one, graphene oxide is used as a structure guiding agent, resorcinol-formaldehyde-melamine is used as a precursor and a nitrogen source, and a sol-gel method is adopted to prepare graphene-based nitrogen-doped phenolic resin;
carbonizing the graphene-based nitrogen-doped phenolic resin prepared in the first step to prepare graphene-based nitrogen-doped hierarchical pore carbon;
and thirdly, carrying out reduction after carrying out palladium precursor on the graphene-based nitrogen-doped hierarchical pore carbon prepared in the second step to obtain the graphene-based nitrogen-doped hierarchical pore carbon-supported palladium catalyst.
According to the preparation method, graphene oxide is used as a structure guiding agent, resorcinol-formaldehyde-melamine is used as a precursor (namely resorcinol and melamine formaldehyde mixed solution), melamine is used as a nitrogen source, a sol-gel method is adopted to prepare graphene-based nitrogen-doped phenolic resin, and then three-dimensional stacked graphene-based nitrogen-doped hierarchical pore carbon nano sheets with nanoscale thickness and higher nitrogen content are obtained through carbonization in sequence, and the three-dimensional stacked graphene-based nitrogen-doped hierarchical pore carbon nano sheets are reduced after palladium precursor is loaded, so that the graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst is obtained. The preparation process organically combines the structural advantage of graphene and the chemical advantage of nitrogen doping, improves the mass transfer performance and the surface chemical performance of the carbon carrier, increases the specific surface area of the catalyst, improves the nitrogen doping content in the catalyst, further improves the dispersity of active component metal palladium, increases the activity of the catalyst, and solves the problems of low Pd utilization rate and poor catalyst activity in the catalyst in the prior art.
The method is characterized in that the specific process of the sol-gel method in the step one is as follows: firstly, respectively preparing resorcinol-formaldehyde solution, melamine-formaldehyde solution and graphene oxide aqueous dispersion, then mixing and carrying out polymerization reaction under water bath stirring; the resorcinol-formaldehyde solution has a resorcinol to formaldehyde molar ratio of 0.5:1, the mole ratio of melamine to formaldehyde in the melamine-formaldehyde solution is 0.33:1, the mole ratio of melamine to resorcinol in the mixed system is 0.5-2: 1, the mass ratio of resorcinol-formaldehyde-melamine to graphene oxide in the mixed system is 40-100: 1, a step of; the temperature of the water bath is 80 ℃, and the polymerization time is 24 hours.
The method is characterized in that in the second step, the carbonization is performed in N 2 The carbonization is carried out in atmosphere at 800 ℃ for 3 hours.
The method is characterized in that the palladium precursor in the third step is at least one of palladium oxide, palladium acetate, palladium nitrate, chloropalladate and sodium chloropalladate, and the reducing agent adopted in the reduction is at least one of formic acid, sodium formate, formaldehyde, hydrazine hydrate, glucose and hydrogen.
The method is characterized in that the palladium precursor is sodium chloropalladate, and the reducing agent is sodium formate.
The invention also discloses application of the graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst in hydrofining of crude terephthalic acid. The graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst disclosed by the invention has the advantages of large specific surface area, high nitrogen content, higher activity on hydrofining of crude terephthalic acid and higher application value.
Compared with the prior art, the invention has the following advantages:
1. according to the graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst, the surface chemical property of the carrier is improved by the carrier-doped nitrogen, the dispersity of active component metal palladium is improved, and the mass transfer performance of the carrier is improved by the hierarchical pore structure, so that the catalytic activity of the catalyst relative to commercial Pd/C is improved.
2. The thickness of the catalyst slice layer is only 20nm, the nitrogen content is approximately 13.5%, the dispersity of the surface palladium is as high as 55%, and the average particle diameter is only 2.0nm.
3. According to the method, graphene oxide is used as a structure guiding agent, resorcinol-formaldehyde-melamine is used as a precursor and nitrogen sources, and a sol-gel method is adopted to combine carbonization and reduction, so that the graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst is obtained, the structural advantage of graphene and the chemical advantage of nitrogen doping are organically combined, the specific surface area and the nitrogen doping content of the catalyst are increased, the activity of the catalyst is increased, and the problems of low Pd utilization rate and poor catalyst activity in the catalyst are solved.
4. According to the invention, the nitrogen content and the lamellar thickness of the carrier are regulated and controlled by changing the mole ratio of the precursor melamine to resorcinol and the mass ratio of resorcinol-formaldehyde-melamine to graphene oxide.
5. The graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst disclosed by the invention has the advantages of large specific surface area, high nitrogen content, higher activity on hydrofining of crude terephthalic acid and higher application value.
The technical scheme of the invention is further described in detail by examples.
Detailed Description
Examples 1 to 6 and comparative example 1 according to the present invention employ H 2 -O 2 The dispersity of Pd in each catalyst is measured by a titration method, and the specific measurement process is as follows: the method comprises the steps of adopting an AutoChemII2920 chemical adsorption instrument of America microphone instrument company as detection equipment, carrying out reduction treatment on a catalyst sample under a hydrogen atmosphere at 200 ℃, then switching an inert gas atmosphere to purge to be stable to a base line, switching oxygen to carry out oxidation, then reducing oxide by pulse hydrogen, calculating the atomic number of surface metal palladium according to the hydrogen consumption, and further calculating the dispersity of Pd.
The nitrogen content in each catalyst was measured using an elemental analyzer (Elemental Vario EL III) in examples 1 to 6 and comparative example 1 of the present invention; the surface morphology of each catalyst sample was observed using a JEOL 7100F field emission Scanning Electron Microscope (SEM) to estimate the catalyst platelet thickness.
Example 1
The graphene-based nitrogen-doped hierarchical pore carbon-supported palladium catalyst comprises the following components in parts by mass: 0.5 part of palladium element, 99.5 parts of graphene-based nitrogen-doped hierarchical pore carbon and 9.1 parts of nitrogen element, wherein the nitrogen element is doped in the graphene-based nitrogen-doped hierarchical pore carbon.
The preparation method of the graphene-based nitrogen-doped hierarchical pore carbon-supported palladium catalyst comprises the following steps:
step one, 7.5g of 12mg/mL Graphene Oxide (GO) water-dispersible mother liquor is subjected to volume fixation to 50mL by deionized water and is subjected to ultrasonic dispersion for 1h to obtain GO dispersion; 2.85g of resorcinol (R) and 4.2g of 37% strength by mass formaldehyde (F) solution were mixed and brought to a volume of 50mL with deionized water, and then subjected to a water bath at 40℃for 30min to give a molar ratio of R to F of 0.5:1, an RF solution of 1; 3.26g of melamine (M) and 6.3g of formaldehyde (F) solution with mass concentration of 37% are taken and mixed and the deionized water is used for constant volume to 50mL, and then water bath is carried out at 80 ℃ for 15min, so that the molar ratio of M to F is 0.33: MF solution of 1;
mixing the GO dispersion liquid, the RF solution and the MF solution, stirring for 24 hours in a water bath at 80 ℃, filtering, and drying at 80 ℃ to obtain the RMF/GO with the mass ratio of 40: 1. the molar ratio M/R is 1:1 graphene-based nitrogen-doped phenolic resin;
step two, the graphene-based nitrogen-doped phenolic resin prepared in the step one is prepared in N 2 Under the protection of air flow, heating to 800 ℃ at a heating rate of 1 ℃/min, and staying for 3 hours for carbonization to prepare graphene-based nitrogen-doped hierarchical pore carbon;
and thirdly, taking the graphene-based nitrogen-doped hierarchical pore carbon prepared in the second step as a carrier, soaking by adopting an aqueous solution of sodium chloropalladate, and reducing by sodium formate to obtain the graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst.
The palladium precursor in this embodiment may be replaced with at least one of palladium oxide, palladium acetate, palladium nitrate, chloropalladate and sodium chloropalladate other than sodium chloropalladate, and the reducing agent used for the reduction may be replaced with at least one of formic acid, sodium formate, formaldehyde, hydrazine hydrate, glucose and hydrogen other than sodium formate.
Examples 2 to 6
According to each step and operation condition of example 1, only the molar ratio of melamine to resorcinol and the mass ratio of resorcinol-formaldehyde-melamine to graphene oxide were changed, and specific values are shown in table 1, so as to prepare the graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst.
TABLE 1
| Catalyst | M/R molar ratio | RMF/GO mass ratio |
| Example 1 | 1：1 | 40：1 |
| Example 2 | 1：1 | 60：1 |
| Example 3 | 1：1 | 80：1 |
| Example 4 | 1：1 | 100：1 |
| Example 5 | 0.5：1 | 40：1 |
| Example 6 | 2：1 | 40：1 |
Detecting the nitrogen content, pd dispersity and lamellar thickness of the graphene-based nitrogen-doped hierarchical pore carbon-supported palladium catalyst prepared in the embodiment 1-6; the graphene-based nitrogen-doped hierarchical pore carbon supported Pd catalyst prepared in the invention examples 1 to 6 and the commercial porous carbon supported Pd catalyst (abbreviated as Pd/C, palladium loading amount 0.5%) purchased in the market are respectively applied to hydrofining of crude terephthalic acid (4-CBA), and the specific process and conditions are as follows: the catalyst loading is 2.0g, crude terephthalic acid is 30.0g,4-CBA is 1.0 g, aqueous solution is 900.0mL, catalytic reduction reaction is carried out in a stainless steel stirring intermittent high-pressure reaction kettle, the reaction pressure is 7.5MPa, the temperature is 280 ℃, quantitative analysis is carried out on the liquid product after the reaction by adopting a high-performance liquid chromatography and an ultraviolet detector, the activity of the catalyst is evaluated by calculating the content of the residual 4-CBA, the lower the content of the residual 4-CBA is, the higher the catalytic hydrogenation efficiency of the catalyst is, and the results are shown in Table 2.
TABLE 2
As can be seen from Table 2, the graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst prepared in examples 1-6 of the invention has nitrogen content significantly higher than that of the commercial Pd/C without nitrogen doping, the Pd dispersity is greatly increased, the thickness of the slice layer is smaller, and the catalyst activity applied to hydrofining of crude terephthalic acid (4-CBA) is as high as 99.6% and is improved compared with that of the commercial Pd/C.
The above description is only of the preferred embodiments of the present invention, and is not intended to limit the present invention. Any simple modification, variation and equivalent variation of the above embodiments according to the technical substance of the invention still fall within the scope of the technical solution of the invention.
Claims (6)
1. The graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst is characterized by comprising the following components in parts by weight: 0.5 part of palladium element, 99.5 parts of graphene-based nitrogen-doped hierarchical pore carbon and 6-14 parts of nitrogen element, wherein the nitrogen element is doped in the graphene-based nitrogen-doped hierarchical pore carbon, and the dispersity of the palladium element in the catalyst is 33% -55%; the catalyst is prepared by a method comprising the following steps:
step one, graphene oxide is used as a structure guiding agent, resorcinol-formaldehyde-melamine is used as a precursor and a nitrogen source, and a sol-gel method is adopted to prepare graphene-based nitrogen-doped phenolic resin; the specific process of the sol-gel method is as follows: firstly, respectively preparing resorcinol-formaldehyde solution, melamine-formaldehyde solution and graphene oxide aqueous dispersion, then mixing and carrying out polymerization reaction under water bath stirring; the temperature of the water bath is 80 ℃, and the polymerization reaction time is 24 hours;
carbonizing the graphene-based nitrogen-doped phenolic resin prepared in the first step to prepare graphene-based nitrogen-doped hierarchical pore carbon;
and thirdly, carrying out reduction after carrying out palladium precursor on the graphene-based nitrogen-doped hierarchical pore carbon prepared in the second step to obtain the graphene-based nitrogen-doped hierarchical pore carbon-supported palladium catalyst.
2. The graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst according to claim 1, wherein the molar ratio of resorcinol to formaldehyde in the resorcinol-formaldehyde solution in step one is 0.5:1, the mole ratio of melamine to formaldehyde in the melamine-formaldehyde solution is 0.33:1, the mole ratio of melamine to resorcinol in the mixed system is 0.5-2: 1, the mass ratio of resorcinol-formaldehyde-melamine to graphene oxide in the mixed system is 40-100: 1.
3. the graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst according to claim 1, wherein the carbonization in step two is performed in N 2 The carbonization is carried out in atmosphere at 800 ℃ for 3 hours.
4. The graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst according to claim 1, wherein in the third step, the palladium precursor is at least one of palladium oxide, palladium acetate, palladium nitrate, chloropalladate and sodium chloropalladate, and the reducing agent used for the reduction is at least one of formic acid, sodium formate, formaldehyde, hydrazine hydrate, glucose and hydrogen.
5. The graphene-based nitrogen-doped hierarchical pore carbon supported palladium catalyst according to claim 4, wherein the palladium precursor is sodium chloropalladate and the reducing agent is sodium formate.
6. Use of the graphene-based nitrogen-doped hierarchical pore carbon-supported palladium catalyst according to claim 1 in hydrofinishing of crude terephthalic acid.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106115693A (en) * | 2016-06-20 | 2016-11-16 | 山东欧铂新材料有限公司 | A kind of composite phenolic resin matrix activated carbon and preparation method thereof, ultracapacitor |
| CN106582763A (en) * | 2016-12-15 | 2017-04-26 | 中国科学院福建物质结构研究所 | Catalyst, preparation method thereof and application in preparation of oxalate |
| CN109806903A (en) * | 2019-03-06 | 2019-05-28 | 中国科学院理化技术研究所 | A kind of monatomic palladium catalyst and its preparation method and application |
| CN110817871A (en) * | 2019-10-09 | 2020-02-21 | 贵州梅岭电源有限公司 | Preparation method and application of nitrogen-doped graphene-based carbon aerogel microspheres |
| CN112237946A (en) * | 2019-07-17 | 2021-01-19 | 中国石油化工股份有限公司 | Terephthalic acid hydrofining reaction and catalyst thereof |
-
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106115693A (en) * | 2016-06-20 | 2016-11-16 | 山东欧铂新材料有限公司 | A kind of composite phenolic resin matrix activated carbon and preparation method thereof, ultracapacitor |
| CN106582763A (en) * | 2016-12-15 | 2017-04-26 | 中国科学院福建物质结构研究所 | Catalyst, preparation method thereof and application in preparation of oxalate |
| CN109806903A (en) * | 2019-03-06 | 2019-05-28 | 中国科学院理化技术研究所 | A kind of monatomic palladium catalyst and its preparation method and application |
| CN112237946A (en) * | 2019-07-17 | 2021-01-19 | 中国石油化工股份有限公司 | Terephthalic acid hydrofining reaction and catalyst thereof |
| CN110817871A (en) * | 2019-10-09 | 2020-02-21 | 贵州梅岭电源有限公司 | Preparation method and application of nitrogen-doped graphene-based carbon aerogel microspheres |
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