CN116462187A - Batch purification method of carbon nano tube - Google Patents
Batch purification method of carbon nano tube Download PDFInfo
- Publication number
- CN116462187A CN116462187A CN202310305734.XA CN202310305734A CN116462187A CN 116462187 A CN116462187 A CN 116462187A CN 202310305734 A CN202310305734 A CN 202310305734A CN 116462187 A CN116462187 A CN 116462187A
- Authority
- CN
- China
- Prior art keywords
- batch
- filter cake
- washing
- carbon nano
- nano tube
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 105
- 229910021393 carbon nanotube Inorganic materials 0.000 title claims abstract description 102
- 239000002041 carbon nanotube Substances 0.000 title claims abstract description 102
- 238000000034 method Methods 0.000 title claims abstract description 57
- 238000000746 purification Methods 0.000 title claims abstract description 30
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims abstract description 74
- 239000012065 filter cake Substances 0.000 claims abstract description 54
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims abstract description 32
- 238000001914 filtration Methods 0.000 claims abstract description 27
- 239000012043 crude product Substances 0.000 claims abstract description 22
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 20
- 230000003647 oxidation Effects 0.000 claims abstract description 18
- 230000001590 oxidative effect Effects 0.000 claims abstract description 13
- 238000005554 pickling Methods 0.000 claims abstract description 11
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000005229 chemical vapour deposition Methods 0.000 claims abstract description 7
- 239000007800 oxidant agent Substances 0.000 claims abstract description 6
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims abstract description 3
- 238000005406 washing Methods 0.000 claims description 85
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 49
- 238000004140 cleaning Methods 0.000 claims description 33
- 239000000047 product Substances 0.000 claims description 29
- 239000002253 acid Substances 0.000 claims description 28
- 239000000706 filtrate Substances 0.000 claims description 25
- 238000006243 chemical reaction Methods 0.000 claims description 23
- 238000010992 reflux Methods 0.000 claims description 18
- 239000007788 liquid Substances 0.000 claims description 16
- 238000001035 drying Methods 0.000 claims description 10
- 230000035484 reaction time Effects 0.000 claims description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract description 7
- 230000000694 effects Effects 0.000 abstract description 6
- 229910052742 iron Inorganic materials 0.000 abstract description 4
- 229910017052 cobalt Inorganic materials 0.000 abstract description 3
- 239000010941 cobalt Substances 0.000 abstract description 3
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 abstract description 3
- 230000000052 comparative effect Effects 0.000 description 23
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 12
- 229910017604 nitric acid Inorganic materials 0.000 description 12
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical class C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 10
- 238000003825 pressing Methods 0.000 description 9
- 239000002270 dispersing agent Substances 0.000 description 8
- 238000001000 micrograph Methods 0.000 description 8
- 238000001878 scanning electron micrograph Methods 0.000 description 8
- 229920000049 Carbon (fiber) Polymers 0.000 description 7
- 239000004917 carbon fiber Substances 0.000 description 7
- 229910021392 nanocarbon Inorganic materials 0.000 description 7
- 238000005303 weighing Methods 0.000 description 7
- 239000000463 material Substances 0.000 description 6
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 5
- 238000005265 energy consumption Methods 0.000 description 5
- 239000011521 glass Substances 0.000 description 5
- TUJKJAMUKRIRHC-UHFFFAOYSA-N hydroxyl Chemical compound [OH] TUJKJAMUKRIRHC-UHFFFAOYSA-N 0.000 description 5
- 238000010298 pulverizing process Methods 0.000 description 5
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 4
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 230000020477 pH reduction Effects 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 238000009210 therapy by ultrasound Methods 0.000 description 3
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000002134 carbon nanofiber Substances 0.000 description 2
- 239000011852 carbon nanoparticle Substances 0.000 description 2
- 229910002804 graphite Inorganic materials 0.000 description 2
- 239000010439 graphite Substances 0.000 description 2
- 238000005087 graphitization Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- WQYVRQLZKVEZGA-UHFFFAOYSA-N hypochlorite Chemical compound Cl[O-] WQYVRQLZKVEZGA-UHFFFAOYSA-N 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 239000011259 mixed solution Substances 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- 239000003495 polar organic solvent Substances 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000011780 sodium chloride Substances 0.000 description 2
- VWDWKYIASSYTQR-UHFFFAOYSA-N sodium nitrate Chemical compound [Na+].[O-][N+]([O-])=O VWDWKYIASSYTQR-UHFFFAOYSA-N 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 238000004065 wastewater treatment Methods 0.000 description 2
- HRPVXLWXLXDGHG-UHFFFAOYSA-N Acrylamide Chemical compound NC(=O)C=C HRPVXLWXLXDGHG-UHFFFAOYSA-N 0.000 description 1
- 229920002126 Acrylic acid copolymer Polymers 0.000 description 1
- LZZYPRNAOMGNLH-UHFFFAOYSA-M Cetrimonium bromide Chemical compound [Br-].CCCCCCCCCCCCCCCC[N+](C)(C)C LZZYPRNAOMGNLH-UHFFFAOYSA-M 0.000 description 1
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical group CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 1
- 239000002033 PVDF binder Substances 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- DBMJMQXJHONAFJ-UHFFFAOYSA-M Sodium laurylsulphate Chemical compound [Na+].CCCCCCCCCCCCOS([O-])(=O)=O DBMJMQXJHONAFJ-UHFFFAOYSA-M 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 229920006322 acrylamide copolymer Polymers 0.000 description 1
- 229920000800 acrylic rubber Polymers 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 125000004103 aminoalkyl group Chemical group 0.000 description 1
- QZPSXPBJTPJTSZ-UHFFFAOYSA-N aqua regia Chemical compound Cl.O[N+]([O-])=O QZPSXPBJTPJTSZ-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- GVGUFUZHNYFZLC-UHFFFAOYSA-N dodecyl benzenesulfonate;sodium Chemical compound [Na].CCCCCCCCCCCCOS(=O)(=O)C1=CC=CC=C1 GVGUFUZHNYFZLC-UHFFFAOYSA-N 0.000 description 1
- 238000005868 electrolysis reaction Methods 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 239000002920 hazardous waste Substances 0.000 description 1
- CABDFQZZWFMZOD-UHFFFAOYSA-N hydrogen peroxide;hydrochloride Chemical compound Cl.OO CABDFQZZWFMZOD-UHFFFAOYSA-N 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002048 multi walled nanotube Substances 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 229920000136 polysorbate Polymers 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 125000001453 quaternary ammonium group Chemical group 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 229940080264 sodium dodecylbenzenesulfonate Drugs 0.000 description 1
- 235000010344 sodium nitrate Nutrition 0.000 description 1
- 239000004317 sodium nitrate Substances 0.000 description 1
- RYYKJJJTJZKILX-UHFFFAOYSA-M sodium octadecanoate Chemical compound [Na+].CCCCCCCCCCCCCCCCCC([O-])=O RYYKJJJTJZKILX-UHFFFAOYSA-M 0.000 description 1
- 159000000000 sodium salts Chemical class 0.000 description 1
- 239000002910 solid waste Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 230000001502 supplementing effect Effects 0.000 description 1
- 229910052723 transition metal Inorganic materials 0.000 description 1
- 150000003624 transition metals Chemical class 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/15—Nano-sized carbon materials
- C01B32/158—Carbon nanotubes
- C01B32/168—After-treatment
- C01B32/17—Purification
Abstract
The invention discloses a batch purification method of carbon nanotubes, which comprises the following steps: step one: dividing a crude product of the carbon nano tube prepared by a chemical vapor deposition method into a plurality of batches; carrying out the same oxidation operation on each batch; the oxidant is one of hydrogen peroxide, ozone or hydroxyl free radicals; filtering to obtain a first filter cake; step two: the first filter cake obtained after the step one oxidation of each batch of carbon nano tube crude products is subjected to hydrochloric acid pickling for 5-8 hours; and filtering to obtain a second filter cake. The batch purification method of the carbon nano tube has good purification effect and higher removal rate of indexes such as iron, cobalt and the like in the crude product of the carbon nano tube.
Description
Technical Field
The invention relates to the technical field of carbon nanotube purification, in particular to a batch purification method of carbon nanotubes.
Background
The carbon nanotube as one new kind of carbon-base material with complete molecular structure has special hollow tubular structure, excellent conductivity, high specific surface area, chemical stability, etc. and may be used in new energy battery, energy storage and semiconductor fields. At present, the preparation process of the carbon nano tube mainly comprises a graphite arc method, a chemical vapor deposition method, a laser evaporation method, an electrolysis method and the like, and the carbon nano tube is produced by the chemical vapor deposition method in industry. Because the transition metal catalyst is used when the carbon nano tube is prepared by the chemical vapor deposition method, the prepared carbon nano tube contains a large amount of metal impurities, such as iron, nickel, cobalt, aluminum and other impurities, and the self-discharge and internal micro-short circuit of the battery can be caused by the high metal content, so that certain potential safety hazard exists. Therefore, there is a need to provide an efficient and convenient purification process to overcome the above problems.
CN109626359a discloses a method for purifying carbon nanotubes, comprising: at the treatment temperature of 90-150 ℃, firstly adopting an aqueous solution of industrial nitric acid to carry out first purification, and then carrying out second purification on the purified carbon nano tube by utilizing an aqueous solution of industrial hydrochloric acid, thereby obtaining the purified carbon nano tube. The method mainly adopts oxidative nitric acid for oxidation, the nitric acid can be replaced by sulfuric acid or hydrofluoric acid, and nickel cannot be treated to below 300ppm after purification. And a large amount of cleaning wastewater is generated, and the field operation environment is bad. The amount of clear water reaches 1/150 of the discharge amount.
CN110104631B discloses a method for purifying carbon nanotubes, wherein the carbon nanotubes are prepared by chemical vapor deposition, and the method comprises the following steps: placing the carbon nano tube in a high-pressure reaction kettle, adding hypochlorite, inorganic acid and a high-boiling-point polar organic solvent to obtain a mixed solution, and performing airtight reaction on the mixed solution at 180-250 ℃ for 5-30 hours to obtain a reaction material; and cooling the reaction material to room temperature, washing with water until the pH value is neutral, and then carrying out solid-liquid separation and drying to obtain the high-purity carbon nanotube, wherein the high-boiling-point polar organic solvent is N-methylpyrrolidone. The method has high energy consumption and high equipment requirement.
CN100562491C is a method for purifying multiwall carbon nanotubes or carbon nanofibers, comprising the following specific steps: (1) Treating the original carbon nano tube or nano carbon fiber sample by a high-temperature graphitization heat treatment method: placing an original carbon nano tube or nano carbon fiber sample into a graphite crucible, and placing into a graphitization furnace; introducing inert gas, and performing heat treatment at 1800-3000 ℃ for 10-300min; (2) Dispersing graphitized carbon nanotubes or carbon nanofibers samples with a dispersant solution while applying ultrasonic treatment: mechanically crushing graphitized carbon nano tubes or nano carbon fibers, immersing the graphitized carbon nano tubes or nano carbon fibers into a dispersing agent solution, stirring for 30-120min, and applying ultrasonic treatment for 10-180min; the dispersing agent is at least one of sodium stearate, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, cetyl trimethyl ammonium bromide, acrylic acid copolymer, hydrolyzed acrylamide, amino alkyl acrylate copolymer, acrylamide copolymer containing quaternary ammonium group, span, tween, polyvinyl alcohol and EO addition product, the weight concentration of the dispersing agent in the dispersing agent solution is 0.01-3%, and the weight of the dispersing agent is 5-60% of the weight of the carbon nano tube or nano carbon fiber; (3) removal of carbon nanoparticles with a mesh filter: filtering the carbon nano tube or nano carbon fiber suspension obtained by dispersing the dispersing agent by using a screen mesh with 200-500 meshes, wherein the non-tubular carbon nano particles are preferentially and stably dispersed in a liquid phase by the dispersing agent, and are separated by filtering; (4) Dispersing the filter cake obtained by filtration in a solvent again for ultrasonic treatment to form suspension, and filtering again; repeating the operation of the step (4) until the filtrate is colorless, and finally obtaining a filter cake which is the highly purified carbon nano tube or nano carbon fiber. The method has the advantages of high energy consumption, high equipment requirement and complex operation.
Therefore, there is a need to develop a simple, efficient, low energy consumption method for purifying carbon nanotubes suitable for production.
Disclosure of Invention
1. The technical problems to be solved are as follows:
the present invention provides a batch purification method for carbon nanotubes.
2. The technical scheme is as follows:
a batch purification method of carbon nanotubes, comprising the steps of:
step one: dividing a crude product of the carbon nano tube prepared by a chemical vapor deposition method into a plurality of batches; carrying out the same oxidation operation on each batch; the oxidant is one of hydrogen peroxide, ozone or hydroxyl free radicals; filtering to obtain a first filter cake;
step two: the first filter cake obtained after the step one oxidation of each batch of carbon nano tube crude products is subjected to hydrochloric acid pickling for 5-8 hours; filtering to obtain a second filter cake;
step three: the second filter cake obtained after the second acid washing of each batch of carbon nano tube crude products is subjected to multiple times of water washing, the water washing temperature is 80-90 ℃, and the pH value of the washed filtrate is about=5; and drying to obtain the pure carbon nanotube product.
Further, the concentration of the hydrogen peroxide is 8-12%.
Further, the reaction temperature of the first step is 20-40 ℃, the oxidation reaction time is 5-8h, and the mass ratio of the crude carbon nano tube to the oxidant is 1:10-16.
Further, the specific steps of the second step are as follows: the first filter cake obtained in the first step of the crude product of the first batch of carbon nanotubes is subjected to reflux cleaning for a plurality of times by adopting clean dilute hydrochloric acid as a cleaning liquid, and the mass ratio of the first filter cake to the dilute hydrochloric acid is 1:10-16; the concentration of the dilute hydrochloric acid is 15-25%; when the first filter cake obtained in the first step of the crude product of each batch of carbon nanotubes after the first batch is subjected to acid washing, clean dilute hydrochloric acid is used as a cleaning liquid for the last acid washing; the nth acid washing before the last acid washing adopts the filtrate generated by the previous batch of the (n+1) th acid washing as a cleaning liquid.
Preferably, the times of pickling the first filter cake obtained in the first step for each batch of crude carbon nano tube are two times.
Further, the specific steps of the third step are as follows: the second filter cake obtained by the second step of the crude product of the first batch of carbon nano tubes is back-washed for a plurality of times by adopting clear water as a cleaning liquid, and when the second filter cake obtained by the second step of the crude product of each batch of carbon nano tubes after the first batch is water-washed, the clear water is used as the cleaning liquid for the last water washing; the M-th water washing before the last time adopts the filtrate generated by the M+1st water washing of the previous batch as the cleaning liquid.
Preferably, the times of washing each batch of the crude carbon nano tube product by the second filter cake generated in the second step are all three times.
3. The beneficial effects are that:
(1) The oxidation temperature is lower when the batch purification method of the carbon nano tube is adopted, and the conventional oxidation process needs to be carried out at 85-100 ℃; the oxidation temperature of the invention is between 20 and 40 ℃, and the energy consumption is lower.
(2) In the traditional process, nitric acid or other oxidizing substances are used for oxidizing the carbon tube; wherein the residual other types of acidic oxides in the carbon nanotubes are mixed with hydrochloric acid in the subsequent acidification process in the post-treatment, so that sodium nitrate/sodium chloride or mixed salts of other sodium salts and sodium chloride are generated; can only be used as solid waste or general hazardous waste for treatment; the hydrogen peroxide, ozone or hydroxyl radical adopted in the process exists in the form of water or oxygen after oxidation, so that mixed salt is not generated, and only sodium chloride salt is used.
(3) In the prior art, nitric acid, hydrofluoric acid and the like are adopted as oxidizing agents, the requirements on the materials of the equipment and the pipelines are high, PVDF special materials are required to be used as inner liners of the equipment, and the processing difficulty is high; after the purification method is adopted, the conventional stainless steel or plastic materials are adopted.
(4) The batch purification method of the carbon nano tube has good purification effect and higher removal rate of indexes such as iron, cobalt and the like in the crude product of the carbon nano tube.
Drawings
FIG. 1 is an SEM image of a crude carbon nanotube product of the present invention;
FIG. 2 is an SEM image of a pure carbon nanotube product obtained in example 1 of the present invention;
FIG. 3 is an SEM image of a pure carbon nanotube product obtained in example 2 of the present invention;
FIG. 4 is an SEM image of a pure carbon nanotube product obtained in example 3 of the present invention;
FIG. 5 is an SEM image of a pure carbon nanotube product obtained in comparative example 1;
FIG. 6 is an SEM image of a pure carbon nanotube product obtained in comparative example 2;
FIG. 7 is an SEM image of a pure carbon nanotube product obtained in comparative example 3;
FIG. 8 is an SEM image of a pure carbon nanotube product obtained in comparative example 4;
FIG. 9 is a flow chart showing the operation of the reaction in example 1 of the present invention;
FIG. 10 is a flow chart showing the operation of the reaction in example 2 of the present invention;
FIG. 11 is a flow chart showing the reaction operation of comparative examples 3 and 4 of the present invention.
Detailed Description
The present invention will be described in detail with reference to fig. 1 to 11.
Example 1:
the embodiment provides a purification method of carbon nanotubes, comprising the following steps:
step one: oxidizing hydrogen peroxide; weighing 0.5kg of crude carbon nano tube, adding 8kg of 10% hydrogen peroxide into a glass reaction kettle, reacting for 6 hours at 20-40 ℃, and pressing into cakes through a high-pressure plate frame for later use; the scanning electron microscope image of the crude product of the carbon nano tube is shown in figure 1,
step two: acid washing; placing the oxidized filter cake back to a reaction kettle, adding 20% clean hydrochloric acid for reflux pickling for 6 hours, pickling twice, wherein the consumption of the hydrochloric acid is 8kg each time, and pressing and filtering the filter cake into a filter cake through a high-pressure plate frame for later use; the filtrate subjected to the first acid washing enters waste liquid treatment, and the filtrate subjected to the second acid washing is collected and then is used for the next batch;
step three: washing with water; washing with clear water for three times at 85deg.C for 15min; washing until the pH is about 5; press-filtering to form cakes, drying and crushing the filter cakes to obtain a pure carbon nanotube product; the filtrate of the first water washing enters into the wastewater treatment, and the filtrate of the second water washing and the filtrate of the third water washing are singly collected and then are used for the next batch; the scanning electron microscope image of the pure carbon nanotube product is shown in fig. 2.
Example 2:
the embodiment provides a purification method of carbon nanotubes, comprising the following steps:
step one: performing ozone oxidation; weighing 0.5kg of carbon nano tube crude product, putting the crude product into a gas-liquid mixing reaction kettle, adding 8kg of pure water, introducing ozone at 20-40 ℃ for reaction for 6 hours, and performing filter pressing through a high-pressure plate frame to form cakes for later use;
step two: acid washing; placing the oxidized filter cake back to a reaction kettle, adding 20% clean hydrochloric acid for reflux pickling for 6 hours, pickling twice, wherein the consumption of the hydrochloric acid is 8kg each time, and pressing and filtering the filter cake into a filter cake through a high-pressure plate frame for later use;
step three: washing with water; washing with clear water for three times; the washing temperature is 85 ℃ and the washing time is 15min; washing until pH reaches about 5, press-filtering to form cake, drying the cake, and pulverizing to obtain pure carbon nanotube product, wherein the scanning electron microscope image of the pure carbon nanotube product is shown in figure 3.
Example 3
The embodiment provides a purification method of carbon nanotubes, comprising the following steps:
step one: oxidizing hydroxyl radicals; weighing 0.5Kg of crude carbon nano tube, adding 8Kg of pure water into a hydroxyl radical generator (electro Fenton device), starting radical generating equipment to react for 6 hours, and performing filter pressing through a high-pressure plate frame to form cakes for later use;
step two: acid washing; placing the oxidized filter cake back to a reaction kettle, adding 20% clean hydrochloric acid for reflux pickling for 6 hours, pickling twice, wherein the consumption of the hydrochloric acid is 8kg each time, and pressing and filtering the filter cake into a filter cake through a high-pressure plate frame for later use;
step three: washing with water; washing with clear water for three times; the washing temperature is 85 ℃ and the washing time is 15min; washing until pH reaches about 5, press-filtering to form cake, drying the cake, and pulverizing to obtain pure carbon nanotube product, wherein the scanning electron microscope image of the pure carbon nanotube product is shown in figure 4.
Comparative example 1:
the embodiment provides a purification method of carbon nanotubes, comprising the following steps:
step one: weighing 0.5kg of crude carbon nano tube, adding 8kg of 10% hydrogen peroxide into a glass reaction kettle, refluxing for 6 hours, and performing filter pressing through a high-pressure plate frame to form cakes for later use;
step two: placing the filter cake back to the reaction kettle, adding 20% clean hydrochloric acid for reflux for 6 hours, and pickling twice, wherein the consumption of the hydrochloric acid is 8kg each time; press-filtering to obtain a filter cake by a high-pressure plate frame for later use; the filtrate of the first acid washing enters into waste liquid treatment, and the filtrate of the second acid washing is collected for standby;
step three: washing with water; washing with clear water twice; the washing temperature is 85 ℃ and the washing time is 15min; washing pH to about 5, press-filtering to form cake, drying the cake, and pulverizing to obtain pure carbon nanotube product, wherein the scanning electron microscope image of the pure carbon nanotube product is shown in figure 5; the filtrate of the first water washing enters into the wastewater treatment, and the filtrate of the second water washing and the filtrate of the third water washing are collected separately for standby.
Comparative example 2:
the embodiment provides a purification method of carbon nanotubes, comprising the following steps:
step one: oxidizing hydrogen peroxide; weighing 0.5kg of crude carbon nano tube, adding 8kg of 10% hydrogen peroxide into a glass reaction kettle, refluxing for 6 hours, and performing filter pressing through a high-pressure plate frame to form cakes for later use;
step two: acid washing is applied mechanically; placing the filter cake obtained by oxidation back to a reaction kettle, adding 8kg of filtrate obtained by the second acid washing in comparative example 1 (the insufficient part is complemented by 20% clean hydrochloric acid) to reflux for 6 hours, wherein the second acid washing adopts 20% clean hydrochloric acid, and the dosage is 8kg; press-filtering to obtain a filter cake by a high-pressure plate frame for later use;
step three: washing with water; washing with water for three times; the first water wash uses the filtrate of the second water wash of comparative example 1; the second water washing was applied to the filtrate of the third water washing in comparative example 1; the third water washing adopts clear water; the washing temperature is 85 ℃ and the washing time is 15min; and after the pH value is washed to about 5, press-filtering to form cakes, drying and crushing the filter cakes to obtain a pure carbon nanotube product, wherein a scanning electron microscope image of the pure carbon nanotube product is shown in figure 6.
Comparative example 3:
the embodiment provides a purification method of carbon nanotubes, comprising the following steps:
step one: oxidizing nitric acid; weighing 0.5kg of crude carbon nano tube, adding 8kg of 40% nitric acid into a glass reaction kettle, refluxing for 6 hours, and performing filter pressing to form cakes through a high-pressure plate frame; putting the filter cake back to the reaction kettle, continuously adding 7Kg of 40% nitric acid, refluxing for 6 hours for the second time, and press-filtering with a high-pressure plate frame to form a filter cake for later use; the filtrate after the second oxidation is collected separately for standby;
step two: washing with water; washing the filter cake obtained by oxidation twice; the washing temperature is 85 ℃ and the washing time is 15min; press-filtering with a high-pressure plate frame to form a filter cake for later use after washing;
step three: acid washing; putting the filter cake obtained by water washing into an acidification kettle, and refluxing twice by adopting 20% hydrochloric acid, wherein the consumption of the hydrochloric acid is 8kg each time, and refluxing for 6 hours; washing hydrochloric acid with pure water to pH of about 5 after refluxing, press-filtering to form cake, drying the filter cake, and pulverizing to obtain pure carbon nanotube product, wherein scanning electron microscope image of the pure carbon nanotube product is shown in figure 7. And independently collecting filtrate after the second acid washing for later use.
Comparative example 4:
the embodiment provides a purification method of carbon nanotubes, comprising the following steps:
step one: oxidizing nitric acid; weighing 0.5Kg of crude carbon nano tube, adding 8Kg of filtrate (less than 40% of clean nitric acid is used for supplementing) collected after the second oxidation of comparative example 2 into a glass reaction kettle, refluxing for 6 hours, press-filtering into cakes through a high-pressure plate frame, putting the filter cakes back into the reaction kettle, continuously adding 7Kg of 40% of clean nitric acid, refluxing for 6 hours for the second time, and press-filtering into filter cakes through the high-pressure plate frame; collecting the filtrate after the second oxidation for the next batch of carbon nano tube purification for reuse;
step two: washing with water; washing the filter cake obtained by oxidation twice; the washing temperature is 85 ℃ and the washing time is 15min; press-filtering with a high-pressure plate frame to form a filter cake for later use after washing;
step three: acid washing; putting the filter cake obtained by water washing into an acidification kettle; 8kg of the filtrate obtained after the second acid washing in comparative example 2 (less than 20% of clean hydrochloric acid) was added for the first acid washing, and the mixture was refluxed for 6 hours; the second acid washing adopts 20% clean hydrochloric acid to reflux for 6 hours, and the consumption of the hydrochloric acid is 8kg; washing hydrochloric acid with pure water to pH of about 5 after refluxing, press-filtering to form cake, drying the filter cake, and pulverizing to obtain pure carbon nanotube product, wherein scanning electron microscope image of the pure carbon nanotube product is shown in figure 8.
Experimental results control:
the metal content of the carbon nanotube crude product purified by the methods of examples 1-3 and comparative examples 1-4 is shown in Table 1.
TABLE 1
As can be seen from the results of comparative examples 1 and 1, the hydrogen peroxide temperature is not significantly improved by the hydrogen peroxide-hydrochloric acid cleaning process, and the hydrogen peroxide temperature is within the range of meeting the product cleaning standard.
As can be seen from the results of comparative examples 1 to 3, the ozone/hydrochloric acid cleaning process, the hydrogen peroxide/hydrochloric acid cleaning process and the hydroxyl radical/hydrochloric acid cleaning process have substantially the same effects. As can be seen from the results of comparative examples 1 to 3 and comparative example 3, the ozone/hydrochloric acid cleaning process, the hydrogen peroxide/hydrochloric acid cleaning process and the hydroxyl radical/hydrochloric acid cleaning process have higher cleaning effects on Fe and Co, and the nitric acid/hydrochloric acid cleaning process has higher cleaning effects on La, mg, ni; but when meeting the product cleaning standard range, the ozone/hydrochloric acid cleaning process, the hydrogen peroxide/hydrochloric acid cleaning process and the hydroxyl radical/hydrochloric acid cleaning process reduce the cleaning flow and save the energy consumption and the water quantity of cleaning compared with the nitric acid-hydrochloric acid cleaning process.
Comparison of comparative example 1 and comparative example 2 and comparison of comparative example 3 and comparative example 4 shows that the use of hydrochloric acid and water jackets has very little effect on the treatment results and is negligible.
While the invention has been described with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention, and it is intended that the scope of the invention shall be limited only by the claims appended hereto.
Claims (7)
1. A batch purification method of carbon nanotubes, comprising the steps of:
step one: dividing a crude product of the carbon nano tube prepared by a chemical vapor deposition method into a plurality of batches; carrying out the same oxidation operation on each batch; the oxidant is one of hydrogen peroxide, ozone or hydroxyl free radicals; filtering to obtain a first filter cake;
step two: the first filter cake obtained after the step one oxidation of each batch of carbon nano tube crude products is subjected to hydrochloric acid pickling for 5-8 hours; filtering to obtain a second filter cake;
step three: the second filter cake obtained after the second acid washing of each batch of carbon nano tube crude products is subjected to multiple times of water washing, the water washing temperature is 80-90 ℃, and the pH value of the washed filtrate is about=5; and drying to obtain the pure carbon nanotube product.
2. The batch purification method of carbon nanotubes according to claim 1, wherein the concentration of hydrogen peroxide is 8-12%.
3. The method according to claim 1, wherein the reaction temperature of the first step is 20-40 ℃, the oxidation reaction time is 5-8 hours, and the mass ratio of the crude carbon nanotube product to the oxidant is 1:10-16.
4. A method for batch purification of carbon nanotubes according to claim 3, wherein the step two is performed as follows: the first filter cake obtained in the first step of the crude product of the first batch of carbon nanotubes is subjected to reflux cleaning for a plurality of times by adopting clean dilute hydrochloric acid as a cleaning liquid, and the mass ratio of the first filter cake to the dilute hydrochloric acid is 1:10-16; the concentration of the dilute hydrochloric acid is 15-25%; when the first filter cake obtained in the first step of the crude product of each batch of carbon nanotubes after the first batch is subjected to acid washing, clean dilute hydrochloric acid is used as a cleaning liquid for the last acid washing; the nth acid washing before the last acid washing adopts the filtrate generated by the previous batch of the (n+1) th acid washing as a cleaning liquid.
5. The method of batch purification of carbon nanotubes of claim 4, wherein the first filter cake obtained in step one is washed twice for each crude batch of carbon nanotubes.
6. The method according to claim 4, wherein the step three comprises the following steps: the second filter cake obtained by the second step of the crude product of the first batch of carbon nano tubes is back-washed for a plurality of times by adopting clear water as a cleaning liquid, and when the second filter cake obtained by the second step of the crude product of each batch of carbon nano tubes after the first batch is water-washed, the clear water is used as the cleaning liquid for the last water washing; the M-th water washing before the last time adopts the filtrate generated by the M+1st water washing of the previous batch as the cleaning liquid.
7. The method of batch purification of carbon nanotubes of claim 6, wherein the number of times each batch of crude carbon nanotubes is washed with water by the second filter cake produced in step two is three.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310305734.XA CN116462187A (en) | 2023-03-27 | 2023-03-27 | Batch purification method of carbon nano tube |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310305734.XA CN116462187A (en) | 2023-03-27 | 2023-03-27 | Batch purification method of carbon nano tube |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116462187A true CN116462187A (en) | 2023-07-21 |
Family
ID=87172647
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310305734.XA Pending CN116462187A (en) | 2023-03-27 | 2023-03-27 | Batch purification method of carbon nano tube |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116462187A (en) |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002265209A (en) * | 2001-03-12 | 2002-09-18 | Kazuyuki Taji | Method for purifying carbon nanotube |
| KR20030046858A (en) * | 2001-12-06 | 2003-06-18 | 한윤봉 | High yield purification of single-walled carbon nanotubes using a combined lquid- and gas-phase purification method |
| US20060251564A1 (en) * | 2004-12-31 | 2006-11-09 | Industrial Technology Research Institute | Carbon nanomaterial purification method |
| JP2008037696A (en) * | 2006-08-04 | 2008-02-21 | Mitsubishi Heavy Ind Ltd | Nanocarbon material production apparatus and nanocarbon material purification method |
| CN101130431A (en) * | 2006-08-23 | 2008-02-27 | 中国科学院金属研究所 | Method for purifying nano carbon fiber of multi-wall carbon nano-tube |
| JP2008290886A (en) * | 2007-05-22 | 2008-12-04 | National Institute Of Advanced Industrial & Technology | Cleaning agent for carbon nanotube, and method for purifying carbon nanotube using the same |
| CN101450798A (en) * | 2007-11-29 | 2009-06-10 | 索尼株式会社 | Method for processing carbon nanotube, carbon nanotube and carbon nanotube element |
| CN205288670U (en) * | 2015-07-16 | 2016-06-08 | 商实企业有限公司 | Washing apparatus |
| CN113860289A (en) * | 2021-10-21 | 2021-12-31 | 江苏天奈科技股份有限公司 | Method for purifying carbon nano tube |
| CN114314566A (en) * | 2021-12-29 | 2022-04-12 | 无锡碳谷科技有限公司 | Separation and purification method of carbon nano tube |
-
2023
- 2023-03-27 CN CN202310305734.XA patent/CN116462187A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002265209A (en) * | 2001-03-12 | 2002-09-18 | Kazuyuki Taji | Method for purifying carbon nanotube |
| KR20030046858A (en) * | 2001-12-06 | 2003-06-18 | 한윤봉 | High yield purification of single-walled carbon nanotubes using a combined lquid- and gas-phase purification method |
| US20060251564A1 (en) * | 2004-12-31 | 2006-11-09 | Industrial Technology Research Institute | Carbon nanomaterial purification method |
| JP2008037696A (en) * | 2006-08-04 | 2008-02-21 | Mitsubishi Heavy Ind Ltd | Nanocarbon material production apparatus and nanocarbon material purification method |
| CN101130431A (en) * | 2006-08-23 | 2008-02-27 | 中国科学院金属研究所 | Method for purifying nano carbon fiber of multi-wall carbon nano-tube |
| JP2008290886A (en) * | 2007-05-22 | 2008-12-04 | National Institute Of Advanced Industrial & Technology | Cleaning agent for carbon nanotube, and method for purifying carbon nanotube using the same |
| CN101450798A (en) * | 2007-11-29 | 2009-06-10 | 索尼株式会社 | Method for processing carbon nanotube, carbon nanotube and carbon nanotube element |
| CN205288670U (en) * | 2015-07-16 | 2016-06-08 | 商实企业有限公司 | Washing apparatus |
| CN113860289A (en) * | 2021-10-21 | 2021-12-31 | 江苏天奈科技股份有限公司 | Method for purifying carbon nano tube |
| CN114314566A (en) * | 2021-12-29 | 2022-04-12 | 无锡碳谷科技有限公司 | Separation and purification method of carbon nano tube |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110523415B (en) | Copper-iron layered double hydroxide, copper-iron layered double hydroxide/carbon-based composite material, and preparation method and application thereof | |
| CN108046248B (en) | Method for preparing graphene from wastewater generated in graphene production | |
| US11845679B2 (en) | Copper integrated electrode with convertible oxidation state and preparation method and application method thereof | |
| CN111001413B (en) | Catalyst for oxidizing and degrading ibuprofen by sulfate radical and preparation method thereof | |
| Wang et al. | Mechanism for enhancing biodegradability of antibiotic pharmacy wastewater by in-situ generation of H2O2 and radicals over MnOx/nano-G/2-EAQ/AC cathode | |
| CN105236387B (en) | A kind of method that basic treatment CNT improves its aqueous dispersion | |
| CN112657493A (en) | Manufacturing method of carbon nanotube film and continuous flow electro-Fenton system based on limited-area catalyst | |
| CN113860289B (en) | Method for purifying carbon nano tube | |
| CN107670691A (en) | One kind is without heterogeneous class Fenton type catalyst of metal and preparation method and application | |
| CN110586063A (en) | Carbon fiber loaded zinc oxide photocatalytic composite material and preparation method thereof | |
| CN116462187A (en) | Batch purification method of carbon nano tube | |
| CN109468709B (en) | Preparation method of graphene-doped Co3O4 mesoporous fiber | |
| CN105236480B (en) | HCOOBiO nanocrystalline with unique morphology and preparation method therefor | |
| CN1887703A (en) | Process of activating carbon nanotube of great specific surface area | |
| CN107162117B (en) | Method for removing perchlorate in water body through electrochemical reduction | |
| CN114516679B (en) | Method for degrading pollutants in water by activating periodate | |
| CN116002668A (en) | Batch purification method for carbon nanotubes and energy-saving device thereof | |
| CN110433804B (en) | Method for preparing silver oxide-doped manganese oxide nanowire network based on electrostatic spinning and application of silver oxide-doped manganese oxide nanowire network in catalytic decomposition of formaldehyde | |
| CN113546653A (en) | Fe-Si-B-P amorphous alloy catalyst for efficiently degrading dye and preparation method and application thereof | |
| CN115626633B (en) | Purification method of single-walled carbon nanotube | |
| CN109626359A (en) | A kind of method of purifying carbon nano-tube and by its carbon nanotube after purification | |
| CN115414953B (en) | Fe-P-C-B-Al amorphous/nanocrystalline alloy ribbon, preparation method thereof and application thereof in degradation of dye | |
| CN106587058A (en) | Method for recovering KOH and refining activated carbon in process of preparing super activated carbon with KOH activation method | |
| CN112850873B (en) | Tubular falling film reactor catalytic activation persulfate treatment system and operation process | |
| CN115304532B (en) | Purification method of N-methyl pyrrolidone |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |