CN115672280B - Preparation method of perfluoro caprylic acid adsorbent - Google Patents
Preparation method of perfluoro caprylic acid adsorbent Download PDFInfo
- Publication number
- CN115672280B CN115672280B CN202211495305.5A CN202211495305A CN115672280B CN 115672280 B CN115672280 B CN 115672280B CN 202211495305 A CN202211495305 A CN 202211495305A CN 115672280 B CN115672280 B CN 115672280B
- Authority
- CN
- China
- Prior art keywords
- activated carbon
- solution
- pyrrole
- fecl
- polypyrrole
- 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.)
- Active
Links
- SNGREZUHAYWORS-UHFFFAOYSA-N perfluorooctanoic acid Chemical compound OC(=O)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)F SNGREZUHAYWORS-UHFFFAOYSA-N 0.000 title claims abstract description 46
- 239000003463 adsorbent Substances 0.000 title claims abstract description 18
- 238000002360 preparation method Methods 0.000 title abstract description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 246
- KAESVJOAVNADME-UHFFFAOYSA-N Pyrrole Chemical compound C=1C=CNC=1 KAESVJOAVNADME-UHFFFAOYSA-N 0.000 claims abstract description 70
- 238000009832 plasma treatment Methods 0.000 claims abstract description 18
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 34
- 239000008367 deionised water Substances 0.000 claims description 20
- 229910021641 deionized water Inorganic materials 0.000 claims description 20
- 238000001035 drying Methods 0.000 claims description 18
- 238000004140 cleaning Methods 0.000 claims description 15
- 238000000967 suction filtration Methods 0.000 claims description 8
- 239000000725 suspension Substances 0.000 claims description 8
- 238000012216 screening Methods 0.000 claims description 6
- 238000005406 washing Methods 0.000 claims description 6
- 238000000034 method Methods 0.000 claims description 5
- 239000007788 liquid Substances 0.000 claims description 3
- 238000007605 air drying Methods 0.000 claims description 2
- IDGUHHHQCWSQLU-UHFFFAOYSA-N ethanol;hydrate Chemical compound O.CCO IDGUHHHQCWSQLU-UHFFFAOYSA-N 0.000 claims description 2
- 238000001914 filtration Methods 0.000 claims description 2
- 238000011010 flushing procedure Methods 0.000 claims description 2
- 238000002156 mixing Methods 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 239000002245 particle Substances 0.000 claims description 2
- 239000007787 solid Substances 0.000 claims description 2
- 229920000128 polypyrrole Polymers 0.000 abstract description 41
- 238000001179 sorption measurement Methods 0.000 abstract description 26
- 239000007864 aqueous solution Substances 0.000 abstract description 5
- 238000012986 modification Methods 0.000 abstract description 5
- 230000004048 modification Effects 0.000 abstract description 5
- 239000000178 monomer Substances 0.000 abstract description 5
- 230000005611 electricity Effects 0.000 abstract description 3
- 238000011065 in-situ storage Methods 0.000 abstract description 2
- 238000006116 polymerization reaction Methods 0.000 abstract 1
- 239000000243 solution Substances 0.000 description 25
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 17
- -1 perfluoro octoate anions Chemical class 0.000 description 13
- 235000013162 Cocos nucifera Nutrition 0.000 description 7
- 244000060011 Cocos nucifera Species 0.000 description 7
- 230000000694 effects Effects 0.000 description 5
- 235000019441 ethanol Nutrition 0.000 description 5
- 238000011049 filling Methods 0.000 description 5
- 230000000052 comparative effect Effects 0.000 description 4
- 238000001816 cooling Methods 0.000 description 4
- 239000000428 dust Substances 0.000 description 4
- 238000000227 grinding Methods 0.000 description 4
- 230000002209 hydrophobic effect Effects 0.000 description 4
- 239000012535 impurity Substances 0.000 description 4
- 230000001105 regulatory effect Effects 0.000 description 4
- 238000007873 sieving Methods 0.000 description 4
- ULUNQYODBKLBOE-UHFFFAOYSA-N 2-(1h-pyrrol-2-yl)-1h-pyrrole Chemical compound C1=CNC(C=2NC=CC=2)=C1 ULUNQYODBKLBOE-UHFFFAOYSA-N 0.000 description 3
- 150000001768 cations Chemical class 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 229910021645 metal ion Inorganic materials 0.000 description 3
- 150000003254 radicals Chemical class 0.000 description 3
- 238000001878 scanning electron micrograph Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- LTVDFSLWFKLJDQ-UHFFFAOYSA-N α-tocopherolquinone Chemical compound CC(C)CCCC(C)CCCC(C)CCCC(C)(O)CCC1=C(C)C(=O)C(C)=C(C)C1=O LTVDFSLWFKLJDQ-UHFFFAOYSA-N 0.000 description 3
- YOALFLHFSFEMLP-UHFFFAOYSA-N azane;2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-pentadecafluorooctanoic acid Chemical compound [NH4+].[O-]C(=O)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)F YOALFLHFSFEMLP-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000012512 characterization method Methods 0.000 description 2
- 238000007323 disproportionation reaction Methods 0.000 description 2
- 239000003651 drinking water Substances 0.000 description 2
- 235000020188 drinking water Nutrition 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 125000000524 functional group Chemical group 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 239000005871 repellent Substances 0.000 description 2
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- 239000004593 Epoxy Substances 0.000 description 1
- 241001411320 Eriogonum inflatum Species 0.000 description 1
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 description 1
- 101001136034 Homo sapiens Phosphoribosylformylglycinamidine synthase Proteins 0.000 description 1
- 206010028980 Neoplasm Diseases 0.000 description 1
- 150000005857 PFAS Chemical class 0.000 description 1
- 102100036473 Phosphoribosylformylglycinamidine synthase Human genes 0.000 description 1
- 230000003213 activating effect Effects 0.000 description 1
- 235000011114 ammonium hydroxide Nutrition 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 201000011510 cancer Diseases 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000000356 contaminant Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 210000003238 esophagus Anatomy 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 125000001153 fluoro group Chemical class F* 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000003673 groundwater Substances 0.000 description 1
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 1
- 210000003734 kidney Anatomy 0.000 description 1
- 210000004185 liver Anatomy 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 230000002085 persistent effect Effects 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 230000000379 polymerizing effect Effects 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 150000003242 quaternary ammonium salts Chemical class 0.000 description 1
- 210000004994 reproductive system Anatomy 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 210000002345 respiratory system Anatomy 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000002798 spectrophotometry method Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000006228 supernatant Substances 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
Abstract
The invention discloses a preparation method of perfluoro caprylic acid adsorbent, which comprises the following steps of N 2 And grafting in situ on the surface of the activated carbon subjected to the plasma treatment to generate polypyrrole. The invention couples the plasma modification technology and the monomer micromolecule polymerization technology, after the active carbon is treated by plasma, the surface of the active carbon has a large amount of free radicals, the ability of the active carbon to adsorb and activate pyrrole is enhanced, and then FeCl is adopted at room temperature 3 The surface of the activated carbon is catalyzed to polymerize pyrrole to generate polypyrrole, so that the modified activated carbon has positive electricity in the surface of the aqueous solution, and the grafted polypyrrole is not easy to fall off from the surface of the activated carbon, thereby improving the adsorption rate and adsorption capacity of the activated carbon to perfluorooctanoic acid.
Description
Technical Field
The invention relates to the technical field of adsorption materials, in particular to a preparation method of a perfluoro caprylic acid adsorbent.
Background
Perfluorooctanoic acid (Perfluorooctanoic acid, PFOA) is commonly used as an oil-and water-repellent and stain-repellent surfactant, dispersant and leveling agent due to its excellent stability, surface activity and hydrophobic oleophobicity. PFOA is an artificial chemical substance which is an organic substance formed by substitution of fluorine atoms by hydrogen atoms on the perfluoroalkyl carbon chain. Because of the strong electronegativity of fluorine, a layer of compact electron cloud can be formed at the periphery of the carbon chain, so that PFOA molecules are stable and difficult to degrade, and the PFOA is easy to accumulate to reach higher concentration particularly in a system with slow water circulation exchange speed, such as groundwater, so that the pollution to water is caused. The research team of Qinghua university investigates the monitoring data of PFAS in the drinking water of 66 cities in China, and finds that the drinking water of a plurality of cities contains PFOA with higher concentration. Studies have shown that PFOA can enter the human body through the respiratory tract, esophagus, etc., causing serious damage to the reproductive system, liver and kidneys of people, and possibly even causing cancer. 2019. PFOA was listed as a persistent organic contaminant (POP) in annex a of the schde gol convention. Therefore, the search for a rapid, efficient and low-cost PFOA removal method has important significance for ecological environment protection and human health.
Activated carbon is the most common carbon adsorbent material. PFOA molecules are large in size, have certain hydrophobic characteristics and exist in the form of perfluoro octoate anions in the solution. Therefore, removal of PFOA in aqueous solutions using both hydrophobic and electrostatic adsorption of adsorbents is the most efficient method. However, the surface of the common activated carbon contains a large amount of oxygen-containing functional groups, the functional groups enable the surface of the activated carbon to be electronegative in an aqueous solution, and perfluoro octoate ions are electronegative in the aqueous solution, so that the surface of the activated carbon is extremely easy to repel, and the adsorption performance of the activated carbon on perfluoro octoate ions is reduced. In the prior art, other compounds which make the active carbon positive are grafted or loaded on the surface of the active carbon, such as metal cations or 3-chloro-2-hydroxypropyl trimethylammonium chloride and the like, so as to achieve the aim of improving the adsorption effect, but the loaded metal ions are easy to fall off from the surface of the active carbon to cause secondary pollution, and the long carbon chain of the epoxy grafted quaternary ammonium salt can increase the steric hindrance (overlapping atomic electron clouds and representing repulsive force) of PFOA adsorption, so that the improvement of the PFOA adsorption performance is influenced.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention aims to provide a preparation method of a perfluoro caprylic acid adsorbent, which aims to solve the problems that the perfluoro caprylic acid adsorption effect of active carbon in the prior art on water is poor and compounds loaded on the surface of the active carbon are easy to fall off.
In order to solve the technical problems, the invention adopts the following technical scheme:
the preparation method of the perfluoro caprylic acid adsorbent specifically comprises the following steps:
step 1: screening the activated carbon, cleaning the activated carbon by deionized water, and drying the activated carbon for later use;
step 2: putting the activated carbon obtained in the step 1 into a plasma cleaning machine, and starting vacuum plasma treatment;
step 3: after glow of the plasma cleaner, N is introduced 2 The treatment duration is 200s-300s;
step 4: mixing the activated carbon treated in the step 3 with a pyrrole solution, and then placing the mixture into a closed container for oscillating for 12-24 hours; the concentration of the pyrrole solution is 0.1-3 mol/L, and the solid-liquid ratio of the active carbon to the pyrrole solution is 1g: (10-50) mL;
step 5: carrying out suction filtration on the suspension obtained in the step 4, and flushing and suction-filtering the obtained solid with an ethanol water solution and a deionized water solution for a plurality of times;
step 6: placing the product washed in the step 5 into a container, and adding FeCl 3 Continuously oscillating the solution for 6-10 hours; wherein FeCl 3 The concentration of the solution is 0.1-5 mol/L, feCl 3 The volume ratio of the solution to the pyrrole solution isV(FeCl 3 Dissolve): v (pyrrole solution) = (5-1): 1;
step 7: and (3) carrying out suction filtration on the suspension obtained in the step (6), washing for a plurality of times by using deionized water, and then air-drying to constant weight to obtain the perfluoro caprylic acid adsorbent.
In the prior art, in order to improve the performance of activated carbon in adsorbing PFOA, the surface of the activated carbon is often directly loaded with metal ions or grafted with compounds such as 3-chloro-2-hydroxypropyl trimethylammonium chloride. However, metal ions are easy to fall off, and the long-chain structure of 3-chloro-2-hydroxypropyl trimethylammonium chloride can increase the steric hindrance of pollutant adsorption and block micropores of the activated carbon, so that the adsorption performance of the activated carbon is improved. According to the invention, the polypyrrole with positive electricity is generated by grafting and polymerizing the surface of the activated carbon in situ, so that the adsorption quantity of the activated carbon to the perfluorooctanoate ions can be increased, and the adsorption speed of the activated carbon to the perfluorooctanoate ions is also improved, thereby improving the adsorption effect of the activated carbon to the perfluorooctanoate ions, and the grafted polypyrrole is not easy to fall off from the surface of the activated carbon to cause secondary pollution.
Compared with the prior art, the invention has the following beneficial effects:
the method of the invention adopts the steps that firstly, the activated carbon is treated by plasma, firstly, the time and N of the plasma treatment are regulated 2 The etching effect of the plasma is utilized to increase the micropore content of the activated carbon, so that the specific surface area of the activated carbon is increased, and the capacity of the activated carbon for adsorbing perfluorooctanoic acid radical is increased from the hydrophobic effect angle of the activated carbon; secondly, activating the surface of the activated carbon by plasma to generate a large amount of cation free radicals. These cationic radicals react with pyrrole to produce pyrrole cationic radicals which are then reacted with FeCl 3 The pyrrole cation free radical generated under the oxidation of (1) collides to generate double-cation dipyrrole containing two cation free radicals, and then the dipyrrole is generated into the electrically neutral dipyrrole through disproportionation. The neutral polypyrrole can be combined with the cationic free radical in the system to generate the cationic free radical of the polypyrrole, then the polypyrrole is generated into the trimeric polypyrrole through disproportionation, and finally the polypyrrole is generated periodically. Thus, the generated polypyrrole is not easy to fall off from the surface of the active carbon, can also show positive electricity in the aqueous solution, and improves the adsorption performance and the adsorption rate of the active carbon on the perfluorooctanoic acid from the electrostatic action angle.
Drawings
Fig. 1 is an SEM image of unmodified activated carbon.
Fig. 2 is an SEM image of polypyrrole-modified activated carbon obtained in example 2.
FIG. 3 is an SEM image of polypyrrole-modified activated carbon obtained in the comparative example.
Fig. 4 is a graph of the PFOA performance evaluation of activated carbon adsorption.
Detailed Description
The invention will be further described with reference to the drawings and examples.
1. Examples
Example 1
(1) Sieving coconut shell activated carbon with a standard sieve, screening activated carbon with 20-60 meshes, washing with deionized water for 3-6 times, removing impurities and dust on the surface of the activated carbon, drying in a blast drying oven at 110 ℃ to constant weight, cooling to room temperature, and filling into a sample bag;
(2) Placing the 2.5 g coconut shell activated carbon obtained in the step (1) in the center of a plasma treatment cavity, closing a cavity door, starting a vacuum pump, vacuumizing the inside of the treatment cavity to ensure that the absolute pressure of the treatment cavity is less than 5kPa, and starting a plasma cleaning machine after maintaining 30s under the absolute pressure. After glow of the plasma cleaning machine, N is regulated 2 After the flow is 100 mL/min and the plasma treatment is 240 s, the vacuum pump is closed, the pressure release is completed when the vacuum gauge reading is 0, the cabin door is opened, and the activated carbon is taken out.
(3) Putting the activated carbon 2.5 and g obtained in the step (2) after plasma treatment into a dry and clean 50 mL grinding conical flask, rapidly adding a pyrrole solution 25 mL with the concentration of 1.0 mol/L into the flask, plugging the flask stopper, putting into a water bath constant temperature oscillator, and oscillating 12h at the speed of 100 r/min at room temperature, so that pyrrole can be uniformly adsorbed on the surface of the activated carbon.
(4) The activated carbon obtained in step (3) was rinsed 3-4 times with 50 vol.% aqueous ethanol and deionized water, respectively, to remove free pyrrole on the surface of the activated carbon, and then the activated carbon was transferred to a dry, clean 100 mL-grind Erlenmeyer flask.
(5) Adding 50 mL mol/L FeCl into the conical flask in the step (4) 3 The solution was placed in a water bath thermostatically shaker and shaken at room temperature at a rate of 100 r/min for 8 h to polymerize the pyrrole monomer on the surface of the activated carbon to form polypyrrole.
(6) And (3) carrying out suction filtration on the suspension obtained in the step (5), cleaning the activated carbon grafted with polypyrrole by using deionized water for 4-5 times, and then drying in a blast drying oven at 110 ℃ until the weight is constant, thus obtaining the activated carbon modified by the polypyrrole.
Example 2
(1) Sieving coconut shell activated carbon with a standard sieve, screening activated carbon with 20-60 meshes, washing with deionized water for 3-6 times, removing impurities and dust on the surface of the activated carbon, drying in a blast drying oven at 110 ℃ to constant weight, cooling to room temperature, and filling into a sample bag;
(2) Placing the 2.5 g coconut shell activated carbon obtained in the step (1) in the center of a plasma treatment cavity, closing a cavity door, starting a vacuum pump, vacuumizing the inside of the treatment cavity to ensure that the absolute pressure of the treatment cavity is less than 5kPa, and starting a plasma cleaning machine after maintaining 30s under the absolute pressure. After glow of the plasma cleaning machine, N is regulated 2 After the flow is 80 mL/min and the plasma treatment is 240 s, the vacuum pump is closed, the pressure release is completed when the vacuum gauge reading is 0, the cabin door is opened, and the activated carbon is taken out.
(3) Putting the activated carbon 2.5 and g obtained in the step (2) after plasma treatment into a dry and clean 50 mL grinding conical flask, rapidly adding a pyrrole solution 25 mL with the concentration of 1.0 mol/L into the flask, plugging the flask stopper, putting into a water bath constant temperature oscillator, and oscillating 12h at the speed of 100 r/min at room temperature, so that pyrrole can be uniformly adsorbed on the surface of the activated carbon.
(4) The activated carbon obtained in step (3) was rinsed 3-4 times with 50 vol.% aqueous ethanol and deionized water, respectively, to remove free pyrrole on the surface of the activated carbon, and then the activated carbon was transferred to a dry, clean 100 mL-grind Erlenmeyer flask.
(5) Adding 50 mL mol/L FeCl into the conical flask in the step (4) 3 The solution was placed in a water bath thermostatically shaker and shaken at room temperature at a rate of 100 r/min for 8 h to polymerize the pyrrole monomer on the surface of the activated carbon to form polypyrrole.
(6) And (3) carrying out suction filtration on the suspension obtained in the step (5), cleaning the activated carbon grafted with polypyrrole by using deionized water for 4-5 times, and then drying in a blast drying oven at 110 ℃ until the weight is constant, thus obtaining the activated carbon modified by the polypyrrole.
Example 3
(1) Sieving coconut shell activated carbon with a standard sieve, screening activated carbon with 20-60 meshes, washing with deionized water for 3-6 times, removing impurities and dust on the surface of the activated carbon, drying in a blast drying oven at 110 ℃ to constant weight, cooling to room temperature, and filling into a sample bag;
(2) Placing the 2.5 g coconut shell activated carbon obtained in the step (1) in the center of a plasma treatment cavity, closing a cavity door, starting a vacuum pump, vacuumizing the inside of the treatment cavity to ensure that the absolute pressure of the treatment cavity is less than 5kPa, and starting a plasma cleaning machine after maintaining 20 s under the absolute pressure. After glow of the plasma cleaning machine is emitted, the flow of N2 is regulated to be 100 mL/min, after plasma treatment is carried out on 240 s, a vacuum pump is turned off, pressure release is completed when the reading of a vacuum meter is 0, a cabin door is opened, and activated carbon is taken out.
(3) Putting the activated carbon 2.5 and g obtained in the step (2) after plasma treatment into a dry and clean 50 mL grinding conical flask, rapidly adding a pyrrole solution 25 mL with the concentration of 3.0 mol/L into the flask, plugging the flask stopper, putting into a water bath constant temperature oscillator, and oscillating 12h at the speed of 100 r/min at room temperature, so that pyrrole can be uniformly adsorbed on the surface of the activated carbon.
(4) The activated carbon obtained in step (3) was rinsed 3-4 times with 50 vol.% aqueous ethanol and deionized water, respectively, to remove free pyrrole on the surface of the activated carbon, and then the activated carbon was transferred to a dry, clean 100 mL-grind Erlenmeyer flask.
(5) Adding 50 mL mol/L FeCl into the conical flask in the step (4) 3 The solution was placed in a water bath thermostatically shaker and shaken at room temperature at a rate of 100 r/min for 8 h to polymerize the pyrrole monomer on the surface of the activated carbon to form polypyrrole.
(6) And (3) carrying out suction filtration on the suspension obtained in the step (5), cleaning the activated carbon grafted with polypyrrole by using deionized water for 4-5 times, and then drying in a blast drying oven at 110 ℃ until the weight is constant, thus obtaining the activated carbon modified by the polypyrrole.
Control example: without plasma pretreatment, the active carbon is directly grafted with polypyrrole
(1) Sieving coconut shell activated carbon with a standard sieve, screening activated carbon with 20-60 meshes, washing with deionized water for 3-6 times, removing impurities and dust on the surface of the activated carbon, drying in a blast drying oven at 110 ℃ to constant weight, cooling to room temperature, and filling into a sample bag;
(2) Putting the activated carbon 2.5 g obtained in the step (1) into a dry and clean 50 mL grinding conical flask, rapidly adding the pyrrole solution 25 mL with the concentration of 1.0 mol/L into the conical flask, plugging the bottle stopper, putting into a water bath constant temperature oscillator, and oscillating 12h at the speed of 100 r/min at room temperature, so that the pyrrole can be uniformly adsorbed on the surface of the activated carbon.
(3) The activated carbon obtained in step (2) was rinsed 3-4 times with 50 vol.% aqueous ethanol and deionized water, respectively, to remove free pyrrole on the surface of the activated carbon, and then the activated carbon was transferred to a dry, clean 100 mL-grind Erlenmeyer flask.
(4) Adding 50 mL mol/L FeCl into the conical flask in the step (3) 3 The solution was placed in a water bath thermostatically shaker and shaken at room temperature at a rate of 100 r/min for 8 h to polymerize the pyrrole monomer on the surface of the activated carbon to form polypyrrole.
(5) And (3) carrying out suction filtration on the suspension obtained in the step (4), cleaning the activated carbon grafted with polypyrrole by using deionized water for 4-5 times, and then drying in a blast drying oven at 110 ℃ until the weight is constant, thus obtaining the activated carbon modified by the polypyrrole.
2. Performance study
SEM characterization was performed on the unmodified activated carbon, the polypyrrole-modified activated carbon obtained in example 1, example 3 and comparative example, and SEM characterization charts obtained are shown in fig. 1, fig. 2 and fig. 3, respectively.
As can be seen from fig. 1, the unmodified activated carbon had a loose surface and a large number of macropores. As can be seen from fig. 2, the activated carbon surface modified with the plasma treatment and grafted polypyrrole has attached to it a number of fluffy particles, which are grafted polypyrrole. As can be seen from FIG. 2, the synthesized substances are not separated from the surface of the activated carbon even though being washed by the absolute ethyl alcohol and the deionized water for a plurality of times, so that the binding force between the polypyrrole and the surface of the activated carbon is strong, and the secondary pollution is not caused by the separation of the polypyrrole from the surface of the activated carbon easily.
As can also be seen from fig. 3, in the comparative example, polypyrrole grafted on the activated carbon without plasma treatment remained mainly in the pores (gaps) of the activated carbon, and the surface was very small, indicating that polypyrrole grafted on the surface of the activated carbon without plasma treatment was easily detached from the surface of the activated carbon when washed with absolute ethanol and deionized water, resulting in secondary pollution.
The performance evaluation of activated carbon, example 1, example 2, example 3, and control for polypyrrole-modified activated carbon to adsorb PFOA was performed by adsorption kinetics experiments. The method comprises the following specific steps:
(1) Preparing 50 mg/L of perfluorooctanoic acid solution by using a volumetric flask, and filling the solution into a plastic bottle for standby;
(2) Accurately weighing 50 mg activated carbon under different modification conditions in a 100 mL ground conical flask by using an analytical balance, accurately sucking 50 mL perfluoro caprylic acid solution in the conical flask by using a pipette, and sealing;
(3) Placing the conical flask into a water bath constant temperature oscillator, and reacting at room temperature; every 12 th h, supernatant 1 mL is taken in a 15 mL plastic tube, and excessive ammonia water is added to make perfluorooctanoic acid completely react to ammonium perfluorooctanoate;
(4) And measuring the concentration of ammonium perfluorooctanoate by adopting an ultraviolet spectrophotometry to further obtain the concentration of PFOA.
As can be seen from fig. 3, when the activated carbon was first plasma-treated and then modified with grafted polypyrrole, examples 1, 2 and 3 had higher adsorption capacity and higher adsorption rate for adsorbing PFOA than the original activated carbon.
Comparing example 1 with example 2, example 2 was plasma treated with N 2 The flow rate was 80 mL/min, which was less than 100 mL/min in example 1, the gas velocity was too low and the discharge intensity was too weak, and the amount of radicals generated on the surface of the activated carbon was less than in example 1, and although the same synthesis conditions as in example 1 were used for grafting polypyrrole, since the amount of cationic radicals on the surface of the activated carbon was less than in example 1, polypyrrole was washed away more than in example 1, resulting in less grafting of polypyrrole on the surface of the activated carbon and generation of static stateThe electric adsorption force was small, so the adsorption performance was lower than that of example 1.
Comparing example 1 with example 3, the polypyrrole modification of example 3 is carried out with a pyrrole concentration of 3.0 mol/L, which is greater than 1.0 mol/L of example 1, i.e. more polypyrrole is grafted on the surface of the activated carbon than in example 1, although the more polypyrrole is grafted on the surface of the activated carbon, the greater the electrostatic adsorption force is generated, which is beneficial to adsorbing PFOA molecules. However, polypyrrole occupies some micropores or mesopores in the activated carbon, and the PFOA molecules are larger, the length is about 1.19 and nm, the width is about 0.38 and nm, the height is about 0.39 and nm, and excessive polypyrrole occupies the PFOA adsorption sites and generates larger adsorption steric hindrance on the PFOA, so that the activated carbon obtained in example 2 has lower adsorption performance on the PFOA than the activated carbon obtained in example 1. In the comparative example, since the activated carbon was not subjected to plasma treatment, the binding force between polypyrrole and the surface of the activated carbon was intermolecular force, the binding force was weak, and when the activated carbon was washed with ethanol and water, the activated carbon was easily peeled off from the surface and only polypyrrole was grafted in micropores or mesopores.
Finally, it should be noted that the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the technical solution, and those skilled in the art should understand that modifications and equivalents may be made to the technical solution of the present invention without departing from the spirit and scope of the present invention, and all such modifications and equivalents are included in the scope of the claims.
Claims (6)
1. The application of the perfluoro caprylic acid adsorbent is characterized in that the adsorbent is prepared by the following method:
step 1: screening the activated carbon, cleaning the activated carbon by deionized water, and drying the activated carbon for later use;
step 2: putting the activated carbon obtained in the step 1 into a plasma cleaning machine, and starting vacuum plasma treatment;
step 3: after glow of the plasma cleaner, N is introduced 2 The treatment duration is 200s-300s;
step 4: mixing the activated carbon treated in the step 3 with a pyrrole solution, and then placing the mixture into a closed container for oscillating for 12-24 hours; the concentration of the pyrrole solution is 0.1-3 mol/L, and the solid-liquid ratio of the active carbon to the pyrrole solution is 1g: (10-50) mL;
step 5: carrying out suction filtration on the suspension obtained in the step 4, and flushing and suction-filtering the obtained solid with an ethanol water solution and a deionized water solution for a plurality of times;
step 6: placing the product washed in the step 5 into a container, and adding FeCl 3 Continuously oscillating the solution for 6-10 hours; wherein FeCl 3 The concentration of the solution is 0.1-5 mol/L, feCl 3 The volume ratio of the solution to the pyrrole solution isV(FeCl 3 Solution):V(pyrrole solution) = (5-1): 1;
step 7: carrying out suction filtration on the suspension obtained in the step 6, washing for a plurality of times by using deionized water, and then air-drying to constant weight to obtain the perfluoro caprylic acid adsorbent;
the perfluoro caprylic acid adsorbent is used for adsorbing perfluoro caprylic acid in water.
2. The use of the perfluorooctanoic acid adsorbent according to claim 1, wherein in step 1, activated carbon having a particle size of 20-60 mesh is selected.
3. The use of the perfluorooctanoic acid adsorbent according to claim 1, wherein in step 2, when the absolute pressure inside the chamber of the plasma cleaning machine is less than 5kPa, the plasma treatment is started after waiting for 30s to 60 s.
4. Use of a perfluorooctanoic acid adsorbent according to claim 1, characterized in that in step 3, N 2 The flow rate is 80 mL/min-120 mL/min.
5. The use of the perfluorooctanoic acid adsorbent according to claim 1, wherein in step 4, the concentration of pyrrole solution is 0.5-3 mol/L; the solid-to-liquid ratio of the activated carbon to the pyrrole solution is 1g: (10-30) mL.
6. The perfluorooctanoic acid adsorbent of claim 1Characterized in that in step 6, feCl is used in step 6 3 The concentration of the solution is 0.1 mol/L to 2 mol/L; feCl 3 The volume ratio of the solution to the pyrrole solution isV(FeCl 3 Solution):V(pyrrole solution) = (3-1): 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211495305.5A CN115672280B (en) | 2022-11-27 | 2022-11-27 | Preparation method of perfluoro caprylic acid adsorbent |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211495305.5A CN115672280B (en) | 2022-11-27 | 2022-11-27 | Preparation method of perfluoro caprylic acid adsorbent |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115672280A CN115672280A (en) | 2023-02-03 |
| CN115672280B true CN115672280B (en) | 2024-01-26 |
Family
ID=85055443
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211495305.5A Active CN115672280B (en) | 2022-11-27 | 2022-11-27 | Preparation method of perfluoro caprylic acid adsorbent |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115672280B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116081778A (en) * | 2023-03-09 | 2023-05-09 | 石河子大学 | Method for recovering fluorine element in perfluoro or polyfluoroalkyl compound from aqueous solution |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20100044312A (en) * | 2008-10-22 | 2010-04-30 | 서울대학교산학협력단 | Adsorption and removal of heavy metal ions using mesoporous carbon/polymer nanocomposite-based filter system |
| CN102730803A (en) * | 2012-07-25 | 2012-10-17 | 大连交通大学 | Application of polypyrrole composite electrode in recycling heavy metals from waste water |
| RU2509564C1 (en) * | 2012-12-03 | 2014-03-20 | Государственное бюджетное учреждение здравоохранения города Москвы Научно-исследовательский институт скорой помощи имени Н.В. Склифосовского Департамента здравоохранения г. Москвы | Free hemoglobin selective plasmosorbent and method for preparing it |
| CN110038534A (en) * | 2019-04-12 | 2019-07-23 | 燕山大学 | The preparation method of the polyether sulfone chelating membrane of chemical graft polyaminopolycarboxylic group functional group |
| CN110112014A (en) * | 2019-06-13 | 2019-08-09 | 天津工业大学 | A kind of carbon fabric-polypyrrole combination electrode material and its preparation method and application |
| CN111346621A (en) * | 2020-03-17 | 2020-06-30 | 太原理工大学 | Preparation method of polypyrrole modified activated carbon |
| CA3166721A1 (en) * | 2020-01-15 | 2021-07-22 | Sunresin New Materials Co.Ltd. | Adsorbent resin for removing perfluorinated pollutants from body of water, preparation therefor, and use thereof |
| CN113880182A (en) * | 2021-09-26 | 2022-01-04 | 宁波方太厨具有限公司 | Preparation method of modified activated carbon filter element |
| CN113908816A (en) * | 2021-11-18 | 2022-01-11 | 南开大学 | Preparation method and application of carbon-based polypyrrole composite material |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10843940B2 (en) * | 2018-04-26 | 2020-11-24 | King Fahd University Of Petroleum And Minerals | Contaminant removal from water using polyelectrolyte coated fly ash |
| WO2020163877A1 (en) * | 2019-02-10 | 2020-08-13 | Battelle Memorial Institute | Sampling for monitoring per- and polyfluoroalkyl substances (pfas) in surface water, groundwater and pore water |
-
2022
- 2022-11-27 CN CN202211495305.5A patent/CN115672280B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20100044312A (en) * | 2008-10-22 | 2010-04-30 | 서울대학교산학협력단 | Adsorption and removal of heavy metal ions using mesoporous carbon/polymer nanocomposite-based filter system |
| CN102730803A (en) * | 2012-07-25 | 2012-10-17 | 大连交通大学 | Application of polypyrrole composite electrode in recycling heavy metals from waste water |
| RU2509564C1 (en) * | 2012-12-03 | 2014-03-20 | Государственное бюджетное учреждение здравоохранения города Москвы Научно-исследовательский институт скорой помощи имени Н.В. Склифосовского Департамента здравоохранения г. Москвы | Free hemoglobin selective plasmosorbent and method for preparing it |
| CN110038534A (en) * | 2019-04-12 | 2019-07-23 | 燕山大学 | The preparation method of the polyether sulfone chelating membrane of chemical graft polyaminopolycarboxylic group functional group |
| CN110112014A (en) * | 2019-06-13 | 2019-08-09 | 天津工业大学 | A kind of carbon fabric-polypyrrole combination electrode material and its preparation method and application |
| CA3166721A1 (en) * | 2020-01-15 | 2021-07-22 | Sunresin New Materials Co.Ltd. | Adsorbent resin for removing perfluorinated pollutants from body of water, preparation therefor, and use thereof |
| CN111346621A (en) * | 2020-03-17 | 2020-06-30 | 太原理工大学 | Preparation method of polypyrrole modified activated carbon |
| CN113880182A (en) * | 2021-09-26 | 2022-01-04 | 宁波方太厨具有限公司 | Preparation method of modified activated carbon filter element |
| CN113908816A (en) * | 2021-11-18 | 2022-01-11 | 南开大学 | Preparation method and application of carbon-based polypyrrole composite material |
Non-Patent Citations (3)
| Title |
|---|
| Yuhao Tian et al..《ACS EST Water》 Electrically Controlled Anion Exchange Based on a Polypyrrole/ Carbon Cloth Composite for the Removal of Perfluorooctanoic Acid.2021,第1卷第2504−2512页. * |
| 刘亚敏.《中国优秀硕士学位论文全文数据库工程科技Ⅰ辑》碳纤维/聚吡咯复合电极制备及电化学性能研究.2018,(第11期),12. * |
| 王赫.《中国博士学位论文全文数据库 工程科技Ⅰ辑》 高比电容微纳米碳纤维基电极的设计与性能研究.2022,(第1期),全文. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115672280A (en) | 2023-02-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Li et al. | Super rapid removal of copper, cadmium and lead ions from water by NTA-silica gel | |
| Zhou et al. | Efficient removal of organic dyes from aqueous solution by rapid adsorption onto polypyrrole–based composites | |
| An et al. | Adsorption of heavy metal ions by iminodiacetic acid functionalized D301 resin: Kinetics, isotherms and thermodynamics | |
| Su et al. | High efficiency extraction of U (VI) from seawater by incorporation of polyethyleneimine, polyacrylic acid hydrogel and Luffa cylindrical fibers | |
| Zhu et al. | Highly efficient and selective removal of Cr (VI) by covalent organic frameworks: Structure, performance and mechanism | |
| Li et al. | Removal of copper from aqueous solution by carbon nanotube/calcium alginate composites | |
| Wang et al. | Collagen/cellulose hydrogel beads reconstituted from ionic liquid solution for Cu (II) adsorption | |
| Wang et al. | Adsorption of Pb (II) on activated carbon prepared from Polygonum orientale Linn.: kinetics, isotherms, pH, and ionic strength studies | |
| Liu et al. | Adsorption of lead (Pb) from aqueous solution with Typha angustifolia biomass modified by SOCl2 activated EDTA | |
| Feng et al. | Graphene oxide wrapped melamine sponge as an efficient and recoverable adsorbent for Pb (II) removal from fly ash leachate | |
| Su et al. | Polyethyleneimine-functionalized Luffa cylindrica for efficient uranium extraction | |
| Huang et al. | 2-Methylol-12-crown-4 ether immobilized PolyHIPEs toward recovery of lithium (i) | |
| CN115672280B (en) | Preparation method of perfluoro caprylic acid adsorbent | |
| Tahmasebi et al. | Performance evaluation of graphene oxide coated on cotton fibers in removal of humic acid from aquatic solutions | |
| Wang et al. | Synthesis of N-methylglucamine modified macroporous poly (GMA-co-TRIM) and its performance as a boron sorbent | |
| Song et al. | Comparison for adsorption of tetracycline and cefradine using biochar derived from seaweed Sargassum sp | |
| WO2021103622A1 (en) | Nicotinamide virtual template surface molecularly imprinted material and preparation method therefor and application thereof | |
| Li et al. | Adsorption characteristics of methylene blue onto the N-succinyl-chitosan-g-polyacrylamide/attapulgite composite | |
| CN113024754B (en) | Preparation method and application of iron oxyhydroxide covalent organic framework composite material | |
| He et al. | Porous β-cyclodextrin nanotubular assemblies enable high-efficiency removal of bisphenol micropollutants from aquatic systems | |
| Luo et al. | N-doped biochar from chitosan gel-like solution: effect of hydrothermal temperature and superior aqueous Cr (VI) removal performance | |
| Klapiszewski et al. | Removal of lead (II) ions by an adsorption process with the use of an advanced SiO/lignin biosorbent | |
| CN113694886A (en) | Magnetic adsorption material with Fenton oxidation catalysis function and preparation method and application thereof | |
| CN111905698A (en) | Modified bentonite-sodium alginate composite gel ball, preparation method thereof and application of modified bentonite-sodium alginate composite gel ball as adsorption material | |
| CN113842889B (en) | Microwave synthesis metal organic framework material DUT-5 (Al), synthesis method and application thereof |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |