CN115772275A - Graphite-phase carbon nitride/nano-cellulose composite hydrogel, and preparation method and application thereof - Google Patents
Graphite-phase carbon nitride/nano-cellulose composite hydrogel, and preparation method and application thereof Download PDFInfo
- Publication number
- CN115772275A CN115772275A CN202211526244.4A CN202211526244A CN115772275A CN 115772275 A CN115772275 A CN 115772275A CN 202211526244 A CN202211526244 A CN 202211526244A CN 115772275 A CN115772275 A CN 115772275A
- Authority
- CN
- China
- Prior art keywords
- hydrogel
- graphite
- carbon nitride
- solution
- phase carbon
- 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
- 239000000017 hydrogel Substances 0.000 title claims abstract description 153
- 239000002131 composite material Substances 0.000 title claims abstract description 84
- JMANVNJQNLATNU-UHFFFAOYSA-N oxalonitrile Chemical compound N#CC#N JMANVNJQNLATNU-UHFFFAOYSA-N 0.000 title claims abstract description 82
- 229920002678 cellulose Polymers 0.000 title claims abstract description 36
- 239000001913 cellulose Substances 0.000 title claims abstract description 36
- 238000002360 preparation method Methods 0.000 title claims abstract description 21
- HDZGCSFEDULWCS-UHFFFAOYSA-N monomethylhydrazine Chemical compound CNN HDZGCSFEDULWCS-UHFFFAOYSA-N 0.000 claims abstract description 70
- PAYRUJLWNCNPSJ-UHFFFAOYSA-N Aniline Chemical compound NC1=CC=CC=C1 PAYRUJLWNCNPSJ-UHFFFAOYSA-N 0.000 claims abstract description 62
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 47
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 40
- 229910002804 graphite Inorganic materials 0.000 claims abstract description 38
- 239000010439 graphite Substances 0.000 claims abstract description 38
- 238000010438 heat treatment Methods 0.000 claims abstract description 33
- ROOXNKNUYICQNP-UHFFFAOYSA-N ammonium persulfate Chemical compound [NH4+].[NH4+].[O-]S(=O)(=O)OOS([O-])(=O)=O ROOXNKNUYICQNP-UHFFFAOYSA-N 0.000 claims abstract description 24
- 239000002135 nanosheet Substances 0.000 claims abstract description 23
- 238000002156 mixing Methods 0.000 claims abstract description 19
- NTOLGSSKLPLTDW-UHFFFAOYSA-N hydrogen sulfate;phenylazanium Chemical compound OS(O)(=O)=O.NC1=CC=CC=C1 NTOLGSSKLPLTDW-UHFFFAOYSA-N 0.000 claims abstract description 15
- 238000007789 sealing Methods 0.000 claims abstract description 14
- FHHJDRFHHWUPDG-UHFFFAOYSA-L peroxysulfate(2-) Chemical compound [O-]OS([O-])(=O)=O FHHJDRFHHWUPDG-UHFFFAOYSA-L 0.000 claims abstract description 13
- 229910001870 ammonium persulfate Inorganic materials 0.000 claims abstract description 12
- 229920000877 Melamine resin Polymers 0.000 claims abstract description 11
- 239000000463 material Substances 0.000 claims abstract description 11
- JDSHMPZPIAZGSV-UHFFFAOYSA-N melamine Chemical compound NC1=NC(N)=NC(N)=N1 JDSHMPZPIAZGSV-UHFFFAOYSA-N 0.000 claims abstract description 11
- 239000003999 initiator Substances 0.000 claims abstract description 10
- IMQLKJBTEOYOSI-GPIVLXJGSA-N Inositol-hexakisphosphate Chemical compound OP(O)(=O)O[C@H]1[C@H](OP(O)(O)=O)[C@@H](OP(O)(O)=O)[C@H](OP(O)(O)=O)[C@H](OP(O)(O)=O)[C@@H]1OP(O)(O)=O IMQLKJBTEOYOSI-GPIVLXJGSA-N 0.000 claims abstract description 9
- IMQLKJBTEOYOSI-UHFFFAOYSA-N Phytic acid Natural products OP(O)(=O)OC1C(OP(O)(O)=O)C(OP(O)(O)=O)C(OP(O)(O)=O)C(OP(O)(O)=O)C1OP(O)(O)=O IMQLKJBTEOYOSI-UHFFFAOYSA-N 0.000 claims abstract description 9
- ZIUHHBKFKCYYJD-UHFFFAOYSA-N n,n'-methylenebisacrylamide Chemical compound C=CC(=O)NCNC(=O)C=C ZIUHHBKFKCYYJD-UHFFFAOYSA-N 0.000 claims abstract description 9
- 229940068041 phytic acid Drugs 0.000 claims abstract description 9
- 235000002949 phytic acid Nutrition 0.000 claims abstract description 9
- 239000000467 phytic acid Substances 0.000 claims abstract description 9
- 239000003513 alkali Substances 0.000 claims abstract description 6
- 239000000243 solution Substances 0.000 claims description 72
- 238000006731 degradation reaction Methods 0.000 claims description 56
- 229920001046 Nanocellulose Polymers 0.000 claims description 35
- 239000000843 powder Substances 0.000 claims description 31
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 24
- 239000011259 mixed solution Substances 0.000 claims description 23
- 238000000034 method Methods 0.000 claims description 20
- 239000008367 deionised water Substances 0.000 claims description 16
- 229910021641 deionized water Inorganic materials 0.000 claims description 16
- 238000003756 stirring Methods 0.000 claims description 15
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 12
- QAOWNCQODCNURD-UHFFFAOYSA-N sulfuric acid Substances OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 8
- 239000000126 substance Substances 0.000 claims description 7
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 6
- 239000002351 wastewater Substances 0.000 claims description 6
- LCPVQAHEFVXVKT-UHFFFAOYSA-N 2-(2,4-difluorophenoxy)pyridin-3-amine Chemical compound NC1=CC=CN=C1OC1=CC=C(F)C=C1F LCPVQAHEFVXVKT-UHFFFAOYSA-N 0.000 claims description 5
- JRKICGRDRMAZLK-UHFFFAOYSA-L peroxydisulfate Chemical compound [O-]S(=O)(=O)OOS([O-])(=O)=O JRKICGRDRMAZLK-UHFFFAOYSA-L 0.000 claims description 5
- CHQMHPLRPQMAMX-UHFFFAOYSA-L sodium persulfate Substances [Na+].[Na+].[O-]S(=O)(=O)OOS([O-])(=O)=O CHQMHPLRPQMAMX-UHFFFAOYSA-L 0.000 claims description 5
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 4
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 4
- USHAGKDGDHPEEY-UHFFFAOYSA-L potassium persulfate Chemical group [K+].[K+].[O-]S(=O)(=O)OOS([O-])(=O)=O USHAGKDGDHPEEY-UHFFFAOYSA-L 0.000 claims description 4
- 229910021529 ammonia Inorganic materials 0.000 claims description 3
- 230000000593 degrading effect Effects 0.000 claims description 2
- 229910052799 carbon Inorganic materials 0.000 claims 1
- 238000005121 nitriding Methods 0.000 claims 1
- 239000003054 catalyst Substances 0.000 abstract description 19
- 230000001699 photocatalysis Effects 0.000 abstract description 12
- 238000007146 photocatalysis Methods 0.000 abstract description 8
- 239000011148 porous material Substances 0.000 abstract description 3
- 239000010865 sewage Substances 0.000 abstract description 2
- 238000002834 transmittance Methods 0.000 abstract description 2
- 230000015556 catabolic process Effects 0.000 description 50
- 239000012425 OXONE® Substances 0.000 description 23
- HJKYXKSLRZKNSI-UHFFFAOYSA-I pentapotassium;hydrogen sulfate;oxido sulfate;sulfuric acid Chemical compound [K+].[K+].[K+].[K+].[K+].OS([O-])(=O)=O.[O-]S([O-])(=O)=O.OS(=O)(=O)O[O-].OS(=O)(=O)O[O-] HJKYXKSLRZKNSI-UHFFFAOYSA-I 0.000 description 23
- 230000000694 effects Effects 0.000 description 13
- 238000010521 absorption reaction Methods 0.000 description 11
- 239000004033 plastic Substances 0.000 description 11
- 238000006243 chemical reaction Methods 0.000 description 8
- 238000005520 cutting process Methods 0.000 description 6
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 6
- 230000003197 catalytic effect Effects 0.000 description 5
- 229920000767 polyaniline Polymers 0.000 description 5
- 238000005070 sampling Methods 0.000 description 5
- 239000007787 solid Substances 0.000 description 5
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 4
- 125000001841 imino group Chemical group [H]N=* 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- 230000003647 oxidation Effects 0.000 description 4
- 238000007254 oxidation reaction Methods 0.000 description 4
- 238000002835 absorbance Methods 0.000 description 3
- 238000001994 activation Methods 0.000 description 3
- 230000004913 activation Effects 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 3
- 239000003344 environmental pollutant Substances 0.000 description 3
- 238000003760 magnetic stirring Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 239000002957 persistent organic pollutant Substances 0.000 description 3
- 231100000719 pollutant Toxicity 0.000 description 3
- 229920000642 polymer Polymers 0.000 description 3
- 239000004065 semiconductor Substances 0.000 description 3
- 238000001228 spectrum Methods 0.000 description 3
- 239000002699 waste material Substances 0.000 description 3
- 229910014033 C-OH Inorganic materials 0.000 description 2
- 229910014570 C—OH Inorganic materials 0.000 description 2
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- 238000005033 Fourier transform infrared spectroscopy Methods 0.000 description 2
- OAKJQQAXSVQMHS-UHFFFAOYSA-N Hydrazine Chemical compound NN OAKJQQAXSVQMHS-UHFFFAOYSA-N 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 230000003213 activating effect Effects 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 150000007942 carboxylates Chemical class 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 125000000524 functional group Chemical group 0.000 description 2
- 238000005286 illumination Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 125000000325 methylidene group Chemical group [H]C([H])=* 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 239000011941 photocatalyst Substances 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000004626 scanning electron microscopy Methods 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 238000010257 thawing Methods 0.000 description 2
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 229920002749 Bacterial cellulose Polymers 0.000 description 1
- 238000001157 Fourier transform infrared spectrum Methods 0.000 description 1
- 235000005811 Viola adunca Nutrition 0.000 description 1
- 240000009038 Viola odorata Species 0.000 description 1
- 235000013487 Viola odorata Nutrition 0.000 description 1
- 235000002254 Viola papilionacea Nutrition 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 239000013543 active substance Substances 0.000 description 1
- 125000004442 acylamino group Chemical group 0.000 description 1
- -1 amino, hydroxyl Chemical group 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 239000005016 bacterial cellulose Substances 0.000 description 1
- 238000010170 biological method Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 239000000356 contaminant Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000003631 expected effect Effects 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000000499 gel Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- 231100000086 high toxicity Toxicity 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000002159 nanocrystal Substances 0.000 description 1
- 239000002121 nanofiber Substances 0.000 description 1
- 239000002086 nanomaterial Substances 0.000 description 1
- 239000002105 nanoparticle Substances 0.000 description 1
- 229910052755 nonmetal Inorganic materials 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000000053 physical method Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 230000004043 responsiveness Effects 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 238000001878 scanning electron micrograph Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 239000012085 test solution Substances 0.000 description 1
- 238000007725 thermal activation Methods 0.000 description 1
- 238000009281 ultraviolet germicidal irradiation Methods 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Images
Classifications
-
- 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
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/30—Wastewater or sewage treatment systems using renewable energies
- Y02W10/37—Wastewater or sewage treatment systems using renewable energies using solar energy
Abstract
The invention discloses a graphite-phase carbon nitride/nano-cellulose composite hydrogel, a preparation method and application thereof, and the preparation method comprises the step of heating melamine in a grading manner to prepare g-C 3 N 4 A nanosheet; mixing N, N' -methylene-bisacrylamide, alkali liquor, initiator and aniline, heating, making the solidified material absorb water to obtain hydrogel, adding concentrated sulfuric acid-aniline solution、g‑C 3 N 4 Mixing the nano-sheets, phytic acid and hydrogel, placing, adding ammonium persulfate, and sealing at low temperature to obtain g-C 3 N 4 Hydrogel composite hydrogel. The composite hydrogel has an obvious porous structure, a compact network structure, complete porous closure, larger pore diameter and high transmittance; the graphite phase carbon nitride is uniformly dispersed, and more binding sites are provided for photocatalysis. The composite hydrogel can be used as a catalyst carrier to act on peroxymonosulfate to synergistically degrade methylhydrazine in sewage by photocatalysis.
Description
Technical Field
The invention relates to the technical field of hydrogel, in particular to a preparation method of graphite-phase carbon nitride/nano-cellulose composite hydrogel and application of the graphite-phase carbon nitride/nano-cellulose composite hydrogel in the field of methylhydrazine catalytic degradation.
Background
Methylhydrazine as a high-energy fuel with excellent performance is widely applied to rocket emission, but has the characteristics of high toxicity, easy decomposition and the like, and is very easy to cause water body pollution in the processes of transportation, cleaning and the like. At present, physical treatment methods, biological treatment methods and chemical treatment methods are widely applied to treatment of methyl hydrazine sewage, but are limited by factors such as cost, reaction rate, degradation mechanism and the like, and the actual methyl hydrazine degradation effect is far from the expected effect by using the physical methods and the biological methods. Chemical methods (including catalytic oxidation, potentiometric acid oxidation, photocatalytic oxidation, and the like) are effective. In which an advanced oxidation technique based on Peroxymonosulfate (PMS) is carried out by generating free radicals (. SO 4) as sulfate radicals - ) The active species with strong oxidizing property as the main can directly degrade and mineralize organic pollutants or improve the biodegradability of the organic pollutants, and simultaneously has strong oxidizing capability and high treatment efficiency, thereby having good application prospect. However, the PMS has a slow reaction rate, and is often combined with an external activation means, such as ultraviolet light activation and thermal activation, and a large amount of energy is required. The ultraviolet activation using the ether sunlight as the energy has the advantages of green, environmental protection and sustainability. The research and development of the corresponding photocatalyst material under ultraviolet light are expected to further improve the decomposition rate of PMS, so that the degradation efficiency of the PMS on methylhydrazine is improved.
Hydrogels are catalyst supports and are used for contaminant degradation as a new trend. The hydrogel as an adsorbing material is widely applied to heavy metal adsorption, organic pollutant removal and the like, and has good adsorption capacity and low price. The functional group has a three-dimensional network structure, is rich in hydrophilic groups, and can introduce specific functional groups such as: amino, hydroxyl, carboxyl, acylamino and the like, and a good platform is established for the loading of the catalyst. The hydrogel is used as a catalyst carrier, so that on one hand, the catalytic activity of the catalyst can be improved, and the degradation efficiency of pollutants is improved; on the other hand, the recycling rate of the catalyst can be improved, and negative effects on the environment are avoided.
Cellulose hydrogel is hydrogel composed of cellulose molecules or cellulose nanoparticles (including cellulose nanofibers, cellulose nanocrystals, bacterial cellulose, etc.). The cellulose surface has a large number of hydroxyl groups and shows strong hydrophilicity, so that the cellulose surface can keep better compatibility with a hydrophilic hydrogel matrix. Because the active hydroxyl group is suitable for various chemical reactions, the interaction between the filler and the matrix can be further enhanced by carrying out surface modification on the cellulose, and the dispersibility of the cellulose is improved.
Graphite phase carbon nitride is used as a polymer semiconductor material, has the forbidden band width of about 2.7eV, and can absorb blue-violet light with the wavelength of less than 475nm in a solar spectrum. Good position of valence and conduction bands, such that g-C 3 N 4 Has good optical performance. In addition, the solar energy photocatalyst has excellent chemical stability and low cost, so that the solar energy catalyst becomes a good solar energy catalyst, and has good application prospects in the fields of energy and environment such as new energy photocatalysis and photocatalytic pollutant treatment. Nanostructure g-C 3 N 4 The method can improve the reaction activity under the illumination condition and simultaneously provide more active sites for photocatalysis, and the related research fields are greatly concerned.
Disclosure of Invention
In order to solve the defects in the prior art, the invention aims to provide a preparation method of graphite-phase carbon nitride/nanocellulose composite hydrogel for hydrazine wastewater treatment, aims to construct a graphite-phase carbon nitride/nanocellulose composite hydrogel activating PMS (permanent magnet system) synergistic photocatalytic coupling system, and solves the technical problems of low efficiency and low reaction rate of the existing chemical treatment method. The composite hydrogel has an obvious porous structure, a compact network structure, complete porous closure, larger pore diameter and high transmittance; the graphite phase carbon nitride is uniformly dispersed, and more binding sites are provided for photocatalysis.
The invention is realized by the following technical scheme.
In one aspect of the invention, a preparation method of graphite-phase carbon nitride/nano-cellulose composite hydrogel is provided, which comprises the following steps:
a. heating melamine in stages to obtain g-C 3 N 4 Powder and g-C 3 N 4 A nanosheet;
b. n, N' -methylene bisacrylamide, alkali liquor, an initiator and aniline in a mass ratio of (5-10): 1: (1-2): (1.5-2.5) stirring and mixing in a water bath to obtain a solution A;
heating the solution A under the condition of water bath until the solution A is solidified, putting the solidified substance into deionized water for absorbing water to obtain hydrogel, and refrigerating the hydrogel for later use;
c. concentrated sulfuric acid-aniline solution, g-C 3 N 4 The mass ratio of the phytic acid to the hydrogel is (2.0-4.0): (0.5-1.0): (0.5-1.0): 1, stirring, mixing, standing, and adding (0.03-0.05) ammonium persulfate into the mixed solution to obtain solution B;
sealing the mixed solution B at low temperature to obtain g-C 3 N 4 Hydrogel-aniline hydrogel.
Preferably, in step a, the melamine is heated to 450-600 ℃ at a heating rate of 1-10 ℃/min and kept for 2-6 h to obtain yellow g-C 3 N 4 A powder;
g to C 3 N 4 Heating the powder to 450-600 ℃ and keeping for 2-6 h to obtain light yellow g-C 3 N 4 Nanosheets.
Preferably, the alkali liquor is sodium hydroxide, potassium hydroxide or ammonia water.
Preferably, the initiator is potassium persulfate, sodium persulfate, or ammonia persulfate.
Preferably, the concentrated sulfuric acid-aniline solution is prepared according to the volume ratio of the concentrated sulfuric acid to the aniline being (20-30): 1.
Preferably, in the step b, the solution A is poured into a rubber head dropper, heated for 3 to 6 hours under the water bath condition of 50 to 70 ℃ until the solution A is completely solidified, the solidified material is taken out to absorb water in deionized water for 20 to 28 hours, and the deionized water is replaced every 5 to 8 hours; the hydrogel is refrigerated for 10 to 15 hours at the temperature of between 12 ℃ below zero and 20 ℃ below zero, and is cut up after being unfrozen for 2 to 6 hours.
Preferably, in the step c, the solution is placed for 2 to 4 hours, and then ammonium persulfate is added into the mixed solution.
Preferably, the hydrogel and the mixed solution are sealed in an environment of 0-5 ℃ for 36-60 h to obtain g-C 3 N 4 The hydrogel is compounded with aniline hydrogel.
The porous structure of the graphite phase carbon nitride/nano cellulose composite hydrogel prepared by the method comes from the steps b and c, the porous structure is generated by repeatedly freezing and thawing the hydrogel in the step b, and the shape of the porous structure is determined by adding aniline and graphite phase carbon nitride in the step c.
The graphite phase carbon nitride is uniformly dispersed, and more binding sites are provided for photocatalysis. And c, adding powder graphite phase carbon nitride nanosheets and compounding with aniline, so that the graphite phase carbon nitride enters the formed hydrogel in a powder diffusion mode. This approach allows for more uniform powder distribution than by introducing graphite phase carbon nitride into the liquid when preparing the hydrogel.
On the other hand, the invention provides the graphite-phase carbon nitride/nano-cellulose composite hydrogel prepared by the method.
In another aspect of the present invention, a method for performing methylhydrazine degradation on the composite hydrogel is provided, which includes:
adding 6-9 g/L graphite phase carbon nitride/nano cellulose composite hydrogel and 0.7-1.0 g/L potassium monopersulfate or potassium monopersulfate into the methyl hydrazine-containing wastewater according to the mass ratio, and performing degradation reaction under the irradiation of an ultraviolet lamp and the pH value of the mixture being 6-8.
Due to the adoption of the technical scheme, the invention has the following beneficial effects:
1. the invention has better degradation effect on the methylhydrazine. Compared with graphite-phase carbon nitride powder, the degradation efficiency of the graphite-phase carbon nitride/nano-cellulose composite hydrogel to methylhydrazine is improved from 20% to 97% within 60min, and the first-order kinetic constant (k) is from 0.00394min -1 Increased to 0.05621min-1, the photocatalysis effect is obviously superior to that of graphite phase nitrogenAnd (3) carbon powder. In the degradation process, the porous structure of the hydrogel provides a passage for transferring methylhydrazine molecules, compared with graphite-phase carbon nitride powder, methylhydrazine can be transferred and aggregated in a catalyst more easily, and meanwhile, the polymer semiconductor polyaniline promotes holes and electrons generated by the graphite-phase carbon nitride under ultraviolet light to be transferred to the surface of a material, so that a better degradation effect is shown.
2. According to the invention, the graphite-phase carbon nitride/nano-cellulose composite hydrogel is synthesized by graphite-phase carbon nitride and polyaniline, and the porous structure of the hydrogel and the photoresponsive performance of the carbon nitride are utilized to realize high-efficiency catalytic activity and stability, so that the effect of efficiently activating persulfate under the illumination condition to degrade pollutants is achieved.
3. The method for degrading the methylhydrazine has wide application range on pH, and the nonmetal catalyst is easy to recycle, has no metal dissolution and secondary pollution, and is more beneficial to practical application.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principles of the invention:
FIG. 1 is a schematic view of a process for preparing a composite hydrogel according to the present invention;
FIG. 2 is a diagram illustrating a process for preparing a composite hydrogel according to the present invention;
FIG. 3 is a scanning electron micrograph of a graphite phase carbon nitride/nanocellulose composite hydrogel;
FIG. 4 is a FT-IR spectrum of a graphite phase carbon nitride/nanocellulose composite hydrogel;
FIG. 5 is an XRD image of a graphite phase carbon nitride/nanocellulose composite hydrogel;
FIGS. 6 (a) and (b) are graphs comparing the effect of the graphite phase carbon nitride powder on the degradation of methylhydrazine with that of the graphite phase carbon nitride/nanocellulose composite hydrogel.
Detailed Description
The invention will be described in detail with reference to the drawings and specific embodiments, which are provided herein for the purpose of illustrating the invention and are not to be construed as limiting the invention.
The preparation method of the graphite-phase carbon nitride/nano-cellulose composite hydrogel provided by the embodiment of the invention comprises the following steps:
step a, preparing g-C by using melamine as a raw material 3 N 4 Nanosheet:
(a1) Putting melamine into an alumina crucible, covering, putting the crucible into a KSL-1200X muffle furnace, heating to 450-600 ℃ at the heating rate of 1-10 ℃/min, and keeping the temperature for 2-6 h to obtain yellow powder which is g-C 3 N 4 Powder;
(a2) Taking the above g-C 3 N 4 Putting the powder into an alumina crucible, covering, putting the alumina crucible into a muffle furnace, heating the alumina crucible to 450-600 ℃ at a heating rate of 1-10 ℃/min, and keeping the temperature for 2-6 h to obtain a light yellow solid which is g-C 3 N 4 Nanosheets.
Step b, preparing hydrogel:
(b1) Mixing and stirring 5-10 parts by mass of N, N' -methylene-bisacrylamide, 1 part by mass of alkali liquor (sodium hydroxide, potassium hydroxide or ammonia water), 1-2 parts by mass of initiator (potassium persulfate, sodium persulfate or ammonia persulfate) and 1.5-2.5 parts by mass of aniline in a water bath for 10-20 min to obtain a solution A;
(b2) Taking a disposable plastic rubber-head dropper with the capacity of 5mL, keeping the head of the rubber-head dropper, cutting off 4cm from the bottom, pouring the solution A into the rubber-head dropper, tightly sealing the solution A by a string, and then putting the solution A into a water bath at 50-70 ℃ for heating for 3-6 h until the solution is completely solidified;
(b3) Cutting the gel head dropper along the sealing line with a pair of scissors, taking out the solidified substance, absorbing water in deionized water for 20-28 h, changing the deionized water every 5-8 h, and recording the water absorption capacity of the hydrogel each time;
(b4) And (3) refrigerating the hydrogel at the temperature of-12 to-20 ℃ for 10 to 15 hours, thawing for 2 to 6 hours, chopping the hydrogel by using a paper cutter, and refrigerating the hydrogel for later use.
Step C, preparation of g-C 3 N 4 Hydrogel composite aniline hydrogel, as shown in fig. 1 and 2:
(c1) Concentrated sulfuric acid-aniline solution, g-C 3 N 4 The mass ratio of the nano sheets to the phytic acid to the hydrogel is (2.0-4.0): (0.51.0): (0.5-1.0): 1, fully stirring and mixing, and standing the mixed solution at normal temperature for 2-4 h;
wherein, the concentrated sulfuric acid-aniline solution is prepared according to the volume ratio of the concentrated sulfuric acid to the aniline being (20-30) to 1;
(c2) Adding 0.03-0.05 part of ammonium persulfate into the mixed solution, and stirring the test solution by using a glass rod to uniformly mix to obtain a solution B;
(c3) Sealing the composite hydrogel and the mixed solution at 0-5 ℃ for 36-60 h to finally obtain dark green g-C 3 N 4 Hydrogel-aniline hydrogel.
As shown in fig. 3, the graphite phase carbon nitride/nanocellulose composite hydrogel showed a porous network structure by SEM analysis.
As shown in FIG. 4, the spectrum of the graphite-phase carbon nitride/nanocellulose composite hydrogel was 2830cm as determined by FTIR analysis -1 Has an absorption peak and is methylene (-CH) 2 ) The vibration stretching peak of (1); at 1580cm -1 An imino (N-H) stretching vibration peak appears, which is a characteristic peak of graphite-phase carbon nitride; at 781cm -1 The imino group at the position vibrates in a non-planar manner and is a stretching vibration absorption peak of the aniline; at 1630cm -1 The absorption peak is a carboxylate (COO-) symmetric stretching vibration peak; at 3390cm -1 The broad peak of hydroxyl (-OH) is caused by a large amount of hydroxyl contained in the hydrogel; 1360cm -1 The characteristic peak indicates the presence of carboxyl (C-OH) groups in the composite hydrogel.
As shown in fig. 5, the three diffraction peaks were 15.3 °,20.7 °,25.2 ° and assigned to the (011), (020) and (200) crystal planes of polyaniline by X-ray diffraction analysis.
The application of the graphite-phase carbon nitride/nano-cellulose composite aniline hydrogel prepared by the method in the treatment of methyl hydrazine-containing wastewater comprises the following steps:
adding 6-9 g/L graphite phase carbon nitride/nano cellulose composite hydrogel and 0.7-1.0 g/L potassium monopersulfate into the methyl hydrazine-containing wastewater according to the mass ratio, and carrying out degradation reaction under the irradiation of an ultraviolet lamp and the pH value of the mixture being 6-8.
The graphite phase carbon nitride/nanocellulose composite hydrogel material prepared by the present invention is further illustrated by the following specific examples.
Example 1
Preparing the graphite-phase carbon nitride/nano-cellulose composite hydrogel:
a, preparation g-C 3 N 4 Nanosheet:
(a1) Heating melamine at a heating rate of 5 deg.C/min to 500 deg.C for 3h to obtain yellow powder of g-C 3 N 4 A powder;
(a2) Taking the above g-C 3 N 4 Heating the powder in a muffle furnace at a heating rate of 5 deg.C/min to 450 deg.C for 6h to obtain a light yellow solid of g-C 3 N 4 A nanosheet.
Step b, preparing hydrogel:
(b1) Mixing and stirring 8 parts by mass of N, N' -methylene-bisacrylamide, 1 part by mass of sodium hydroxide, 1 part by mass of initiator potassium persulfate and 2 parts by mass of aniline in a water bath for 15min to obtain a solution A;
(b2) Taking 5mL of plastic rubber-head dropper, keeping the head of the plastic rubber-head dropper, cutting off 4cm from the bottom, pouring the solution A into the rubber-head dropper, tightly tying and sealing the solution A by using a string, and then putting the solution A into a 65 ℃ water bath to heat for 5 hours until the solution is completely solidified;
(b3) Taking out the solidified product to absorb water for 25 hours in deionized water, changing the deionized water every 6 hours, and recording the water absorption capacity of the hydrogel each time;
(b4) The hydrogel is refrigerated at-15 deg.C for 12h, thawed for 4h, and cut with a paper cutter.
Step C, preparation of g-C 3 N 4 Hydrogel composite aniline hydrogel:
(c1) Concentrated sulfuric acid-aniline solution, g-C 3 N 4 The mass ratio of the nanosheets to the phytic acid to the hydrogel is 2.0:0.8:0.5:1, fully stirring and mixing, and standing the mixed solution for 3 hours at normal temperature;
wherein, the concentrated sulfuric acid-aniline solution is prepared according to the volume ratio of concentrated sulfuric acid to aniline being 25;
(c2) Adding 0.03 part of ammonium persulfate into the mixed solution, and uniformly mixing to obtain a solution B;
(c3) Sealing the composite hydrogel and the mixed solution at 5 deg.C for 36h to obtain dark green g-C 3 N 4 Hydrogel-aniline hydrogel.
Example 2
Preparing the graphite-phase carbon nitride/nano-cellulose composite hydrogel:
a, preparation g-C 3 N 4 Nanosheet:
(a1) Heating melamine at a heating rate of 8 deg.C/min to 450 deg.C for 4h to obtain yellow powder g-C 3 N 4 Powder;
(a2) Taking the above g-C 3 N 4 Heating the powder in a muffle furnace at a heating rate of 8 deg.C/min to 500 deg.C for 4h to obtain a light yellow solid in the form of g-C 3 N 4 Nanosheets.
Step b, preparing hydrogel:
(b1) Mixing and stirring 5 parts by mass of N, N' -methylene-bisacrylamide, 1 part by mass of potassium hydroxide, 1.5 parts by mass of initiator sodium persulfate and 1.5 parts by mass of aniline in a water bath for 20min to obtain a solution A;
(b2) Taking 5mL of plastic dropper, keeping the head of the plastic dropper, cutting off 4cm from the bottom, pouring the solution A into the plastic dropper, tightly sealing the solution A with a string, and heating in a water bath at 50 ℃ for 6h until the solution is completely solidified;
(b3) Taking out the solidified product to absorb water for 20 hours in deionized water, changing the deionized water every 8 hours, and recording the water absorption capacity of the hydrogel each time;
(b4) The hydrogel is refrigerated at-18 deg.C for 14h, thawed for 2h, and cut with a paper cutter.
Step C, preparation of g-C 3 N 4 Hydrogel composite aniline hydrogel:
(c1) Concentrated sulfuric acid-aniline solution, g-C 3 N 4 The mass ratio of the nanosheets to the phytic acid to the hydrogel is 3.0:0.5:0.7:1, fully stirring and mixing, and standing the mixed solution for 2 hours at normal temperature;
wherein, the concentrated sulfuric acid-aniline solution is prepared according to the volume ratio of concentrated sulfuric acid to aniline being 30;
(c2) Adding 0.04 part of ammonium persulfate into the mixed solution, and uniformly mixing to obtain a solution B;
(c3) Sealing the composite hydrogel and the mixed solution at 2 deg.C for 40 hr to obtain dark green g-C 3 N 4 Hydrogel-aniline hydrogel.
Example 3
Preparing the graphite-phase carbon nitride/nano-cellulose composite hydrogel:
a, preparation g-C 3 N 4 Nanosheet:
(a1) Heating melamine at a heating rate of 10 ℃/min to 550 ℃ for 2 hours to obtain a yellow powder of g-C 3 N 4 Powder;
(a2) Taking the above g-C 3 N 4 Heating the powder in a muffle furnace at a heating rate of 10 deg.C/min to 600 deg.C for 2h to obtain light yellow solid (g-C) 3 N 4 Nanosheets.
Step b, preparing hydrogel:
(b1) Mixing and stirring 10 parts by mass of N, N' -methylene bisacrylamide, 1 part by mass of ammonia water, 2 parts by mass of initiator ammonium persulfate and 2.5 parts by mass of aniline in a water bath for 10min to obtain a solution A;
(b2) Taking 5mL of plastic rubber-head dropper, keeping the head of the plastic rubber-head dropper, cutting off 4cm from the bottom, pouring the solution A into the rubber-head dropper, tightly tying and sealing the solution A by using a string, and then putting the solution A into a water bath at 55 ℃ for heating for 4h until the solution is completely solidified;
(b3) Taking out the solidified product, absorbing water in deionized water for 28 hours, changing the deionized water every 5 hours, and recording the water absorption capacity of the hydrogel each time;
(b4) The hydrogel is refrigerated at-20 deg.C for 10h, thawed for 6h, and cut with a paper cutter.
Step C, preparation of g-C 3 N 4 Hydrogel composite aniline hydrogel:
(c1) Concentrated sulfuric acid-aniline solution, g-C 3 N 4 The mass ratio of the nanosheets to the phytic acid to the hydrogel is 3.5:1.0:1.0:1, fully stirring and mixing, and standing the mixed solution at normal temperature for 4 hours;
wherein, the concentrated sulfuric acid-aniline solution is prepared according to the volume ratio of concentrated sulfuric acid to aniline being 20;
(c2) Adding 0.05 part of ammonium persulfate into the mixed solution, and uniformly mixing to obtain a solution B;
(c3) Sealing the composite hydrogel and the mixed solution at 4 deg.C for 50 hr to obtain dark green g-C 3 N 4 The hydrogel is compounded with aniline hydrogel.
Example 4
Preparing the graphite-phase carbon nitride/nano-cellulose composite hydrogel:
a, preparation g-C 3 N 4 Nanosheet:
(a1) Heating melamine at a heating rate of 1 deg.C/min to 600 deg.C for 6h to obtain yellow powder g-C 3 N 4 Powder;
(a2) Taking the above g-C 3 N 4 Heating the powder in a muffle furnace at a heating rate of 1 deg.C/min to 550 deg.C for 5h to obtain a light yellow solid in the form of g-C 3 N 4 Nanosheets.
Step b, preparing hydrogel:
(b1) Mixing and stirring 6 parts by mass of N, N' -methylene bisacrylamide, 1 part by mass of sodium hydroxide, 1.6 parts by mass of initiator sodium persulfate and 2.2 parts by mass of aniline in a water bath for 18min to obtain a solution A;
(b2) Taking 5mL of plastic rubber dropper, keeping the head of the plastic dropper, cutting off 4cm from the bottom, pouring the solution A into the plastic dropper, tightening and sealing the solution A by using a string, and then putting the solution A into a 70 ℃ water bath to heat for 3 hours until the solution is completely solidified;
(b3) Taking out the solidified product to absorb water for 22 hours in deionized water, changing the deionized water every 7 hours, and recording the water absorption capacity of the hydrogel each time;
(b4) The hydrogel is refrigerated at-12 deg.C for 15h, thawed for 3h, and cut with a paper cutter.
Step C, preparation of g-C 3 N 4 Hydrogel composite aniline hydrogel:
(c1) Concentrated sulfuric acid-aniline solution, g-C 3 N 4 The mass ratio of the nanosheets to the phytic acid to the hydrogel is 4.0:0.5:0.6:1, fully stirring and mixing, and standing the mixed solution for 3 hours at normal temperature;
wherein, the concentrated sulfuric acid-aniline solution is prepared according to the volume ratio of concentrated sulfuric acid to aniline being 20;
(c2) Then 0.035 part of ammonium persulfate is added into the mixed solution and is uniformly mixed to obtain a solution B;
(c3) Sealing the composite hydrogel and the mixed solution at 0 deg.C for 60 hr to obtain dark green g-C 3 N 4 The hydrogel is compounded with aniline hydrogel.
The graphite-phase carbon nitride/nano-cellulose composite aniline hydrogel prepared by the method is prepared.
The performance of the graphite-phase carbon nitride/nanocellulose composite aniline hydrogel material prepared in the example was tested.
The product comprises the following components: 5mL of 99% acrylic acid, 10mL of 0.05mol/L sodium hydroxide solution, 0.5mL of 0.063g/mL ammonium persulfate solution, 1mL of 0.042g/mL N, N' -methylene-bisacrylamide solution, 2.72mL of 98% concentrated sulfuric acid and 0.582g of g-C 3 N 4 0.114mL aniline and 0.413g phytic acid.
The structure is as follows: as shown in fig. 3, the graphite phase carbon nitride/nanocellulose composite hydrogel showed a porous network structure by SEM analysis.
As shown in FIG. 4, the spectrum of the graphite phase carbon nitride/nanocellulose composite hydrogel was 2830cm by FTIR analysis -1 Has an absorption peak and is methylene (-CH) 2 ) The vibration stretching peak of (1); at 1580cm -1 An imino (N-H) stretching vibration peak appears at the position, which is a characteristic peak of graphite phase carbon nitride; at 781cm -1 The imino group in the position is subjected to non-planar vibration and is a stretching vibration absorption peak of the aniline; at 1630cm -1 The absorption peak is a symmetrical stretching vibration peak of carboxylate (COO-); at 3390cm -1 The broad peak of hydroxyl (-OH) is caused by a large amount of hydroxyl contained in the hydrogel; 1360cm -1 The characteristic peak indicates the presence of carboxyl (C-OH) groups in the composite hydrogel.
As shown in fig. 5, the three diffraction peaks were 15.3 °,20.7 °,25.2 ° and assigned to the (011), (020) and (200) crystal planes of polyaniline by X-ray diffraction analysis.
The graphite phase carbon nitride/nano-cellulose composite hydrogel is applied to the treatment of the methyl hydrazine-containing wastewater, the degradation capability of the graphite phase carbon nitride/nano-cellulose composite hydrogel to the methyl hydrazine in an activated PMS photocatalytic coupling system is explored, and the graphite phase carbon nitride/nano-cellulose composite hydrogel material is adopted to degrade the methyl hydrazine in the wastewater.
1. Different amounts of catalyst
In order to study the methyl hydrazine degradation efficiency under different graphite phase carbon nitride/nano cellulose composite hydrogel adding amounts, 6.0g/L,7.0g/L,8.0g/L and 9.0g/L of graphite phase carbon nitride/nano cellulose composite hydrogel were added into two beakers filled with 20mg/L of methyl hydrazine solution, respectively, and the above operations were performed. Measuring the absorbance value of the solution after sampling at a specified time sampling point, and finally selecting the corresponding methylhydrazine concentration (C) at the time of 60min after adding peroxymonosulfate f ) With the initial concentration (C) 0 ) The ratio of (the concentration of methylhydrazine at the time of adding peroxymonosulfate) represents the degradation efficiency of methylhydrazine in the solution under the corresponding addition amount of the graphite-phase carbon nitride/nanocellulose composite hydrogel.
100mL of an aqueous solution of methylhydrazine at a concentration of 20mg/L was added to a reactor, and simultaneously 6.0, 7.0, 8.0, and 9.0g/L of the graphite-phase carbon nitride/nanocellulose composite hydrogel obtained in example 1 and 1.0g/L of potassium monopersulfate or potassium monopersulfate were added to the reactor, and magnetic stirring was performed in a reactor, and the reaction was performed under UV irradiation at pH =8, and the experimental results were measured after 60 min.
The methylhydrazine removal rate under different catalyst addition conditions is shown in table 1.
Table 1: degradation effect of different catalyst dosage on methylhydrazine
When the amount of potassium monopersulfate or potassium monopersulfate added was 1.0g/L, the methylhydrazine concentration was 20mg/L, and pH =8, the efficiency of methylhydrazine degradation increased with the increase in catalyst addition, but after the catalyst addition exceeded 9g/L, the efficiency of methylhydrazine degradation began to decrease, so it is presumed that the optimum amount of catalyst for this experiment to degrade the methylhydrazine-simulated waste liquid was 9g/L.
The result shows that the graphite phase carbon nitride/nano-cellulose composite hydrogel has the function of catalyzing peroxymonosulfate to degrade methylhydrazine, and the degradation efficiency of methylhydrazine is improved with the increase of the graphite phase carbon nitride/nano-cellulose composite hydrogel. The reason is that in the degradation process, the pore structure of the hydrogel provides a path for transferring methyl hydrazine molecules, and the methyl hydrazine molecules can be more easily aggregated in the composite hydrogel along with the increase of the content of the composite hydrogel, so that better degradation condition is shown.
2. Different persulfate dosage
The methylhydrazine degradation efficiency of the graphite-phase carbon nitride/nanocellulose composite hydrogel under the environments with different amounts of PMS is improved. In order to study the degradation efficiency of methylhydrazine in the graphite-phase carbon nitride/nanocellulose composite hydrogel under different PMS amounts, 100mL of 20mg/L methylhydrazine aqueous solution is added into a reactor, 0.7 g/L potassium monopersulfate or potassium monopersulfate and 9g/L of the graphite-phase carbon nitride/nanocellulose composite hydrogel obtained in example 1 are added into the reactor, magnetic stirring is carried out in a reactor, reaction is carried out under the conditions of normal temperature and pH =8 under the irradiation of a UV lamp, and the experimental result is tested after 60 min.
The methylhydrazine removal rates under different potassium monopersulfate or potassium monopersulfate addition levels are shown in table 2.
Table 2: degradation effect of different PMS dosage on methylhydrazine
| Amount of PMS used | 0.7g/L | 0.8g/L | 0.9g/L | 1.0g/ |
| 60 minute degradation rate | 95％ | 96.5％ | 97.4％ | 98％ |
Measuring the absorbance value of the solution after sampling at a specified time sampling point, calculating the corresponding methylhydrazine concentration, and finally selecting the methylhydrazine concentration (C) corresponding to the degradation time of 60min after adding peroxymonosulfate f ) With the initial concentration (C) 0 ) The ratio of (the concentration of methylhydrazine at the time of adding peroxymonosulfate) represents the degradation efficiency of methylhydrazine in the solution under the corresponding addition amount of the graphite-phase carbon nitride/nanocellulose composite hydrogel.
When the amount of the added catalyst is 9g/L, the methylhydrazine concentration is 20mg/L, and pH =8, the methylhydrazine degradation efficiency is improved with the increase of the addition amount of potassium monopersulfate or potassium monopersulfate, but the methylhydrazine degradation efficiency begins to decrease after the addition amount of potassium monopersulfate or potassium monopersulfate exceeds 1.0g/L, so it can be presumed that the optimum amount of potassium monopersulfate or potassium monopersulfate for the degradation of the methylhydrazine simulant waste liquid in this experiment is 1.0g/L.
The graphite-phase carbon nitride/nano-cellulose composite hydrogel has the function of catalyzing peroxymonosulfate to degrade methyl hydrazine, and within a certain range, the degradation efficiency of the methyl hydrazine is improved along with the increase of the concentration of the peroxymonosulfate in the solution. This is due to the passing of sulfurThe increase of the addition amount of acid salt generates sulfate radical (SO) 4 · - ) The strong oxidizing active substances are increased, thereby greatly improving the degradation efficiency of the methylhydrazine.
3. Different initial pH
In order to research the degradation efficiency of the methylhydrazine of the graphite phase carbon nitride/nanocellulose composite hydrogel in different pH environments, four experimental groups are arranged, before the graphite phase carbon nitride/nanocellulose composite hydrogel is added, a sodium hydroxide (NaOH) solution is used for changing the pH value of the methylhydrazine solution, so that the pH values of beakers of the four experimental groups are respectively 6,7,8 and 10, the adding amount of the graphite phase carbon nitride/nanocellulose composite hydrogel is controlled to be 9.0g/L, and the adding amount of potassium monopersulfate or potassium monopersulfate is 1.0g/L. Measuring absorbance value of the solution after sampling at a specified time, calculating corresponding methylhydrazine concentration, and selecting the methylhydrazine concentration (C) corresponding to 60min degradation time after adding peroxymonosulfate f ) With initial concentration (C) 0 ) The ratio of (the concentration of methylhydrazine at the time of adding peroxymonosulfate) represents the degradation efficiency of methylhydrazine in the solution under the corresponding addition amount of the graphite-phase carbon nitride/nanocellulose composite hydrogel.
100mL of an aqueous solution of methylhydrazine at a concentration of 20mg/L was charged into a reactor, 1.0g/L of potassium monopersulfate or potassium monopersulfate and 8.39g/L of the ink-phase carbon nitride/nanocellulose composite hydrogel obtained in example 1 were charged into the reactor while changing the initial pH =6, 7,8, 10, and magnetic stirring was performed in a reactor, and the reaction was performed under irradiation of a UV lamp at room temperature, and the experimental results were measured after 60 min.
The removal rate of methylhydrazine under different pH conditions is shown in Table 3.
Table 3: effect of different initial pH on Methylhydrazine degradation
| Initial pH | 6 | 7 | 8 | 10 |
| 60 minute degradation rate | 95.2％ | 98％ | 98.8％ | 80.2％ |
The result shows that the degradation of the hydrogel has pH responsiveness, wherein the degradation efficiency is highest under a neutral condition of pH =7, and the degradation rate reaches 98% in 60 min; the degradation efficiency is slowest under the weak acidic condition when the pH =6, and the degradation efficiency is only 95.2% in 60 min; the degradation rate at 60min under the condition of pH =8 is 98.8%; the degradation rate in alkaline environment of pH =10 for 60min was 80.2%. The result shows that the graphite-phase carbon nitride/nano-cellulose composite hydrogel not only has the function of catalyzing peroxymonosulfate to degrade methyl hydrazine, but also has pH influence on degradation, and the catalytic degradation efficiency is highest under a neutral condition.
When the amount of the added catalyst is 9g/L, the amount of potassium monopersulfate or potassium monopersulfate is 1.0g/L, and the concentration of the methylhydrazine is 20mg/L, the degradation efficiency of the methylhydrazine is improved along with the increase of pH, but the degradation efficiency of the methylhydrazine begins to decrease after the initial pH exceeds 8, so that the optimal initial pH for the experimental degradation of the methylhydrazine simulation waste liquid is supposed to be 8.
As shown in fig. 6 (a) and (b), the present invention has a better degradation effect on methylhydrazine than graphite-phase carbon nitride powder. Compared with graphite-phase carbon nitride powder, the degradation efficiency of the graphite-phase carbon nitride/nano-cellulose composite hydrogel to methylhydrazine is improved from 20% to 99% within 60min, and the first-order kineticsConstant (k) from 0.00394min -1 Increase to 0.05621min -1， The photocatalysis function is obviously better than that of graphite phase carbon nitride powder. In the degradation process, the porous structure of the hydrogel provides a passage for transferring methyl hydrazine molecules, compared with graphite-phase carbon nitride powder, methyl hydrazine can be transferred and gathered in a catalyst more easily, and meanwhile, the polymer semiconductor polyaniline promotes holes and electrons generated by the graphite-phase carbon nitride under ultraviolet light to be transferred to the surface of the material, so that a better degradation effect is shown.
The present invention is not limited to the above-mentioned embodiments, and based on the technical solutions disclosed in the present invention, those skilled in the art can make some substitutions and modifications to some technical features without creative efforts according to the disclosed technical contents, and these substitutions and modifications are all within the protection scope of the present invention.
Claims (10)
1. A preparation method of graphite phase carbon nitride/nano cellulose composite hydrogel is characterized by comprising the following steps:
a. heating melamine in stages to obtain g-C 3 N 4 Powder and g-C 3 N 4 Nanosheets;
b. n, N' -methylene-bisacrylamide, alkali liquor, an initiator and aniline in a mass ratio of (5-10): 1: (1-2): (1.5-2.5) stirring and mixing in a water bath to obtain a solution A;
heating the solution A under the condition of water bath until the solution A is solidified, putting the solidified substance into deionized water for absorbing water to obtain hydrogel, and refrigerating the hydrogel for later use;
c. concentrated sulfuric acid-aniline solution, g-C 3 N 4 The nano-sheet, the phytic acid and the hydrogel are mixed according to the mass ratio of (2.0-4.0): (0.5-1.0): (0.5-1.0): 1, stirring, mixing, standing, and adding (0.03-0.05) ammonium persulfate into the mixed solution to obtain solution B;
sealing the mixed solution B at low temperature to obtain g-C 3 N 4 Hydrogel-aniline hydrogel.
2. The graphite phase nitriding of claim 1The preparation method of the carbon/nano-cellulose composite hydrogel is characterized in that in the step a, melamine is heated to 450-600 ℃ at the heating rate of 1-10 ℃/min and is kept for 2-6 h to obtain yellow g-C 3 N 4 Powder;
g to C 3 N 4 Heating the powder to 450-600 ℃ and keeping for 2-6 h to obtain light yellow g-C 3 N 4 Nanosheets.
3. The method for preparing the graphite-phase carbon nitride/nanocellulose composite hydrogel according to claim 1, wherein said alkali solution is sodium hydroxide, potassium hydroxide or ammonia water.
4. The method for preparing a graphite-phase carbon nitride/nanocellulose composite hydrogel according to claim 1, wherein said initiator is potassium persulfate, sodium persulfate, or ammonia persulfate.
5. The method for preparing the graphite-phase carbon nitride/nanocellulose composite hydrogel according to claim 1, wherein the concentrated sulfuric acid-aniline solution is prepared according to a volume ratio of concentrated sulfuric acid to aniline of (20-30): 1.
6. The preparation method of the graphite-phase carbon nitride/nano-cellulose composite hydrogel according to claim 1, wherein in the step b, the solution A is poured into a rubber head dropper, the solution A is heated for 3 to 6 hours under the condition of water bath at 50 to 70 ℃ until the solution A is completely solidified, the solidified material is taken out and is absorbed in deionized water for 20 to 28 hours, and the deionized water is replaced every 5 to 8 hours; the hydrogel is refrigerated for 10 to 15 hours at the temperature of between 12 ℃ below zero and 20 ℃ below zero, and is cut up after being unfrozen for 2 to 6 hours.
7. The method for preparing the graphite-phase carbon nitride/nano-cellulose composite hydrogel according to claim 1, wherein in the step c, the mixture is placed for 2 to 4 hours, and then ammonium persulfate is added into the mixed solution.
8. The graphite phase carbon nitride/nanocellulose composite of claim 1The preparation method of the hydrogel is characterized in that the hydrogel and the mixed solution are sealed in an environment with the temperature of 0-5 ℃ for 36-60 h to obtain g-C 3 N 4 Hydrogel-aniline hydrogel.
9. A graphite phase carbon nitride/nanocellulose composite hydrogel prepared by the method of any one of claims 1 to 8.
10. A method for degrading methylhydrazine by using the composite hydrogel of claim 9, which comprises:
adding 6-9 g/L graphite phase carbon nitride/nano cellulose composite hydrogel and 0.7-1.0 g/L peroxymonosulfate into the methyl hydrazine-containing wastewater according to the mass ratio, and performing degradation reaction under the irradiation of an ultraviolet lamp and with the pH value of 6-8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211526244.4A CN115772275A (en) | 2022-11-30 | 2022-11-30 | Graphite-phase carbon nitride/nano-cellulose composite hydrogel, and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211526244.4A CN115772275A (en) | 2022-11-30 | 2022-11-30 | Graphite-phase carbon nitride/nano-cellulose composite hydrogel, and preparation method and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115772275A true CN115772275A (en) | 2023-03-10 |
Family
ID=85390778
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211526244.4A Pending CN115772275A (en) | 2022-11-30 | 2022-11-30 | Graphite-phase carbon nitride/nano-cellulose composite hydrogel, and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115772275A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090110932A1 (en) * | 2007-10-30 | 2009-04-30 | Cheng-Chien Yang | Polyaniline/carbon black composite and preparation method thereof |
| CN109876845A (en) * | 2019-03-22 | 2019-06-14 | 北京交通大学 | M-g-C3N4The preparation method and application of/rGOA composite adsorption visible light catalytic material |
| CN110980917A (en) * | 2019-11-18 | 2020-04-10 | 河北工业大学 | Method for degrading printing and dyeing wastewater by using graphite-phase carbon nitride activated persulfate under dark reaction condition |
| WO2022051898A1 (en) * | 2020-09-08 | 2022-03-17 | 东莞理工学院 | Magnetic composite light catalyst and production method therefor, and application in antibiotic wastewater treatment |
| CN114456527A (en) * | 2022-02-08 | 2022-05-10 | 西北工业大学深圳研究院 | nanocellulose/g-C3N4/polyacrylamide composite hydrogel and preparation method and application thereof |
-
2022
- 2022-11-30 CN CN202211526244.4A patent/CN115772275A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090110932A1 (en) * | 2007-10-30 | 2009-04-30 | Cheng-Chien Yang | Polyaniline/carbon black composite and preparation method thereof |
| CN109876845A (en) * | 2019-03-22 | 2019-06-14 | 北京交通大学 | M-g-C3N4The preparation method and application of/rGOA composite adsorption visible light catalytic material |
| CN110980917A (en) * | 2019-11-18 | 2020-04-10 | 河北工业大学 | Method for degrading printing and dyeing wastewater by using graphite-phase carbon nitride activated persulfate under dark reaction condition |
| WO2022051898A1 (en) * | 2020-09-08 | 2022-03-17 | 东莞理工学院 | Magnetic composite light catalyst and production method therefor, and application in antibiotic wastewater treatment |
| CN114456527A (en) * | 2022-02-08 | 2022-05-10 | 西北工业大学深圳研究院 | nanocellulose/g-C3N4/polyacrylamide composite hydrogel and preparation method and application thereof |
Non-Patent Citations (3)
| Title |
|---|
| JIANG WENJUN ET AL.: "Polyaniline/carbon nitride nanosheets composite hydrogel: A separation-free and high-efficient photocatalyst with 3D hierarchical structure", 《SMALL》, vol. 12, no. 32, 24 August 2016 (2016-08-24), pages 4370 - 4378 * |
| NIU PING ET AL.: "Graphene-Like Carbon Nitride Nanosheets for Improved Photocatalytic Activities", 《ADVANCED FUNCTIONAL MATERIAS》, vol. 22, no. 22, 21 November 2012 (2012-11-21), pages 4763 - 4770 * |
| 钱周琦;杜晓琳;刘琳;: "掺Br氮化碳-纤维素复合材料的制备及其对亚甲基蓝的光催化降解性能", 浙江理工大学学报(自然科学版), no. 06, 26 February 2018 (2018-02-26), pages 686 - 691 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108706573A (en) | A kind of graphene-based hollow cobalt sulfide nanocrystalline and preparation method thereof that can efficiently activate persulfate | |
| CN111495367B (en) | Magnetic polyaniline-porous carbon-Fe 3 O 4 Preparation method and application of photo-Fenton catalyst | |
| Rasheed et al. | Synthesis and studies of ZnO doped with g-C3N4 nanocomposites for the degradation of tetracycline hydrochloride under the visible light irradiation | |
| CN106492847B (en) | Cellulose nanometer fibril aeroge of negative photocatalyst-bearing and preparation method thereof | |
| CN111154027B (en) | Preparation method and application of temperature-sensitive composite hydrogel utilizing photocatalysis and temperature-sensitive synergistic effect | |
| CN109046229B (en) | Lanthanum hydroxide modified hydroxyapatite material and preparation method and application thereof | |
| CN110624566B (en) | CuInS2Preparation method and application of quantum dot/NiAl-LDH composite photocatalyst | |
| CN104828902A (en) | Method for treating chrome-containing wastewater by catalytic reduction of petaloid magnetic iron oxide/molybdenum sulfide composite | |
| CN104607228A (en) | Preparation method for alpha-Fe2O3 quantum dot/nitrogen-doped graphene composite material | |
| CN105642248A (en) | Formaldehyde filter screen composite material for air purifier and preparation method thereof | |
| CN114797781B (en) | Preparation method of lanthanum-loaded nitrogen-doped porous carbon-phosphorus adsorption material | |
| CN115569668B (en) | Preparation method and application of ternary double-quantum dot synergistic Z electron transfer mechanism composite photocatalytic material | |
| CN111530490A (en) | Co3O4-TiO2Heterojunction loaded carbon nanotube photocatalytic degradation material and preparation method thereof | |
| CN106467323B (en) | A kind of copper-iron-carbon silica aerogel electrode preparation method | |
| CN104549400A (en) | Visible light response type TiO2 nanotube array, as well as preparation method and applications thereof | |
| CN105536773B (en) | Substrate catalyst of making pottery and preparation method thereof | |
| CN109499563A (en) | A kind of preparation method of zinc oxide-active carbon composite catalyst | |
| CN108940349A (en) | The method of carbonitride Z-type photochemical catalyst removal dyestuff contaminant is mixed using siliver chromate/sulphur | |
| CN113441142A (en) | Preparation method and application of oxygen vacancy-rich graphene-loaded porous nano ferroelectric oxide catalyst | |
| CN113716647A (en) | Application of zinc indium sulfide/black phosphorus nanosheet photocatalytic activation ferrate degradation antibiotic | |
| CN111013588B (en) | Fenton-like catalyst and preparation method and application thereof | |
| CN115772275A (en) | Graphite-phase carbon nitride/nano-cellulose composite hydrogel, and preparation method and application thereof | |
| CN106902760A (en) | A kind of eggshell load zinc oxide material and its preparation method and application | |
| CN108940348A (en) | Siliver chromate/sulphur mixes carbonitride Z-type photochemical catalyst and preparation method thereof | |
| CN106944077B (en) | Preparation method of desulfurization material for biogas purification |
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 |