CN112551525A - Method for preparing activated carbon by combining urine and biomass and performance analysis - Google Patents
Method for preparing activated carbon by combining urine and biomass and performance analysis Download PDFInfo
- Publication number
- CN112551525A CN112551525A CN202011568266.8A CN202011568266A CN112551525A CN 112551525 A CN112551525 A CN 112551525A CN 202011568266 A CN202011568266 A CN 202011568266A CN 112551525 A CN112551525 A CN 112551525A
- Authority
- CN
- China
- Prior art keywords
- adsorption
- urine
- activated carbon
- sample
- equation
- 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.)
- Withdrawn
Links
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 159
- 210000002700 urine Anatomy 0.000 title claims abstract description 89
- 238000000034 method Methods 0.000 title claims abstract description 51
- 238000004458 analytical method Methods 0.000 title claims abstract description 43
- 239000002028 Biomass Substances 0.000 title claims abstract description 40
- 235000009496 Juglans regia Nutrition 0.000 claims abstract description 47
- 235000020234 walnut Nutrition 0.000 claims abstract description 47
- 238000001179 sorption measurement Methods 0.000 claims description 171
- 241000758789 Juglans Species 0.000 claims description 46
- 239000000243 solution Substances 0.000 claims description 41
- 239000003463 adsorbent Substances 0.000 claims description 29
- 230000008569 process Effects 0.000 claims description 25
- 239000011148 porous material Substances 0.000 claims description 24
- 229960000907 methylthioninium chloride Drugs 0.000 claims description 23
- 238000002835 absorbance Methods 0.000 claims description 21
- 239000002156 adsorbate Substances 0.000 claims description 17
- 239000000843 powder Substances 0.000 claims description 17
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 17
- 239000007864 aqueous solution Substances 0.000 claims description 16
- 238000010438 heat treatment Methods 0.000 claims description 13
- 239000003610 charcoal Substances 0.000 claims description 12
- JMANVNJQNLATNU-UHFFFAOYSA-N oxalonitrile Chemical compound N#CC#N JMANVNJQNLATNU-UHFFFAOYSA-N 0.000 claims description 12
- 239000002994 raw material Substances 0.000 claims description 12
- 238000001994 activation Methods 0.000 claims description 11
- 230000004913 activation Effects 0.000 claims description 11
- 239000012190 activator Substances 0.000 claims description 11
- 239000002356 single layer Substances 0.000 claims description 11
- 238000012512 characterization method Methods 0.000 claims description 9
- 125000000524 functional group Chemical group 0.000 claims description 9
- 238000003763 carbonization Methods 0.000 claims description 8
- 238000001035 drying Methods 0.000 claims description 8
- 238000000197 pyrolysis Methods 0.000 claims description 8
- 238000003756 stirring Methods 0.000 claims description 8
- 238000009826 distribution Methods 0.000 claims description 7
- 238000012933 kinetic analysis Methods 0.000 claims description 7
- 238000002441 X-ray diffraction Methods 0.000 claims description 6
- 238000004140 cleaning Methods 0.000 claims description 6
- 230000000630 rising effect Effects 0.000 claims description 6
- 238000005303 weighing Methods 0.000 claims description 6
- 230000015572 biosynthetic process Effects 0.000 claims description 5
- 230000008859 change Effects 0.000 claims description 5
- 238000011160 research Methods 0.000 claims description 5
- 238000012360 testing method Methods 0.000 claims description 5
- XSQUKJJJFZCRTK-UHFFFAOYSA-N urea group Chemical group NC(=O)N XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims description 5
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 4
- 229920001807 Urea-formaldehyde Polymers 0.000 claims description 4
- 238000013019 agitation Methods 0.000 claims description 4
- 238000005119 centrifugation Methods 0.000 claims description 4
- 238000013499 data model Methods 0.000 claims description 4
- 238000009792 diffusion process Methods 0.000 claims description 4
- 238000005485 electric heating Methods 0.000 claims description 4
- 230000003993 interaction Effects 0.000 claims description 4
- 239000007788 liquid Substances 0.000 claims description 4
- 239000004570 mortar (masonry) Substances 0.000 claims description 4
- 238000006068 polycondensation reaction Methods 0.000 claims description 4
- 238000004566 IR spectroscopy Methods 0.000 claims description 3
- 238000000354 decomposition reaction Methods 0.000 claims description 3
- 238000007865 diluting Methods 0.000 claims description 3
- 230000002349 favourable effect Effects 0.000 claims description 3
- 238000000227 grinding Methods 0.000 claims description 3
- 229920002521 macromolecule Polymers 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims description 3
- 238000003825 pressing Methods 0.000 claims description 3
- 238000002156 mixing Methods 0.000 claims description 2
- RBTBFTRPCNLSDE-UHFFFAOYSA-N 3,7-bis(dimethylamino)phenothiazin-5-ium Chemical compound C1=CC(N(C)C)=CC2=[S+]C3=CC(N(C)C)=CC=C3N=C21 RBTBFTRPCNLSDE-UHFFFAOYSA-N 0.000 claims 6
- 230000003213 activating effect Effects 0.000 abstract description 7
- 239000003795 chemical substances by application Substances 0.000 abstract description 7
- 239000002699 waste material Substances 0.000 abstract description 5
- 238000002360 preparation method Methods 0.000 abstract description 4
- 230000008901 benefit Effects 0.000 abstract description 2
- 230000007613 environmental effect Effects 0.000 abstract description 2
- 238000004064 recycling Methods 0.000 abstract description 2
- 240000007049 Juglans regia Species 0.000 abstract 1
- 239000000126 substance Substances 0.000 description 24
- CXKWCBBOMKCUKX-UHFFFAOYSA-M methylene blue Chemical compound [Cl-].C1=CC(N(C)C)=CC2=[S+]C3=CC(N(C)C)=CC=C3N=C21 CXKWCBBOMKCUKX-UHFFFAOYSA-M 0.000 description 18
- 230000000694 effects Effects 0.000 description 14
- 239000007789 gas Substances 0.000 description 9
- OMOVVBIIQSXZSZ-UHFFFAOYSA-N [6-(4-acetyloxy-5,9a-dimethyl-2,7-dioxo-4,5a,6,9-tetrahydro-3h-pyrano[3,4-b]oxepin-5-yl)-5-formyloxy-3-(furan-3-yl)-3a-methyl-7-methylidene-1a,2,3,4,5,6-hexahydroindeno[1,7a-b]oxiren-4-yl] 2-hydroxy-3-methylpentanoate Chemical compound CC12C(OC(=O)C(O)C(C)CC)C(OC=O)C(C3(C)C(CC(=O)OC4(C)COC(=O)CC43)OC(C)=O)C(=C)C32OC3CC1C=1C=COC=1 OMOVVBIIQSXZSZ-UHFFFAOYSA-N 0.000 description 8
- 239000000463 material Substances 0.000 description 8
- 238000006243 chemical reaction Methods 0.000 description 7
- 229910052799 carbon Inorganic materials 0.000 description 5
- 239000003575 carbonaceous material Substances 0.000 description 5
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 5
- 239000002585 base Substances 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 4
- 230000006870 function Effects 0.000 description 4
- 238000010521 absorption reaction Methods 0.000 description 3
- 239000002253 acid Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000031700 light absorption Effects 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 238000002425 crystallisation Methods 0.000 description 2
- 230000008025 crystallization Effects 0.000 description 2
- 230000006378 damage Effects 0.000 description 2
- 238000003795 desorption Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 238000004375 physisorption Methods 0.000 description 2
- 238000004626 scanning electron microscopy Methods 0.000 description 2
- 230000037303 wrinkles Effects 0.000 description 2
- 241000196324 Embryophyta Species 0.000 description 1
- 241000282414 Homo sapiens Species 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 230000003113 alkalizing effect Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000004202 carbamide Substances 0.000 description 1
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000003518 caustics Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000002329 infrared spectrum Methods 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 244000144972 livestock Species 0.000 description 1
- 238000001000 micrograph Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 125000004433 nitrogen atom Chemical group N* 0.000 description 1
- -1 nitrogen-containing compound Chemical class 0.000 description 1
- 239000005416 organic matter Substances 0.000 description 1
- 244000144977 poultry Species 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000004080 punching Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/30—Active carbon
- C01B32/312—Preparation
- C01B32/318—Preparation characterised by the starting materials
- C01B32/324—Preparation characterised by the starting materials from waste materials, e.g. tyres or spent sulfite pulp liquor
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/30—Active carbon
- C01B32/312—Preparation
- C01B32/342—Preparation characterised by non-gaseous activating agents
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
- G01N21/3563—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light for analysing solids; Preparation of samples therefor
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
- G01N23/20—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by using diffraction of the radiation by the materials, e.g. for investigating crystal structure; by using scattering of the radiation by the materials, e.g. for investigating non-crystalline materials; by using reflection of the radiation by the materials
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
- G01N23/22—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material
- G01N23/225—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material using electron or ion
- G01N23/2251—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material using electron or ion using incident electron beams, e.g. scanning electron microscopy [SEM]
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
- G01N2021/3595—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light using FTIR
Landscapes
- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Pathology (AREA)
- Organic Chemistry (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Inorganic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Materials Engineering (AREA)
- Crystallography & Structural Chemistry (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention discloses a method for preparing activated carbon by combining urine and biomass and performance analysis. Compared with the prior art, the invention has the advantages that: the urine is used as an activating agent to activate the biomass to prepare the activated carbon, so that the loss of instruments is reduced, the activated carbon is very environment-friendly and low in cost, the source of the activated carbon widely achieves the aim of treating wastes with wastes, the biomass such as walnut has great value in the aspects of environmental protection and resource recycling, the urine is used as an innovative activating agent, the urine and the activating agent provide cheaper biological basis for the preparation of the activated carbon, and the activated carbon is convenient to popularize.
Description
Technical Field
The invention relates to the field of ecological environment protection, in particular to a method for preparing activated carbon by combining urine and biomass and performance analysis.
Background
The population of China is 14 hundred million, and most of urine is discharged to the sea in a chemical treatment mode, and some urine is directly discharged to the nature without being well or even well treated, so that the local environment is greatly polluted. By directly collecting local urine. And the urine is mixed with the waste walnut shells according to a certain proportion, so that the urine can be directly utilized once, and the pollution of the urine directly discharged to the nature is reduced to a certain extent. Meanwhile, the substances in the urine after reaction are much less than those in the urine before reaction, and the urine is simply treated again. The requirement for the treatment capability of sewage recovery is reduced, and the urine types are not limited to human beings, and the urine of livestock can also be used. Can be subsidized to poultry farmers in remote villages by only providing urine. Most of traditional activators are corrosive substances such as strong acid, strong base, oxidizing salt and the like, for a processing plant, the cost value spent on maintaining machines is high every year, the activators after reaction without proper treatment still have certain corrosivity, and if the activators are directly discharged to the nature in the factory, the activators can cause great harm to a local ecological system. And the oxidizing salt of strong acid and strong base is high in price. This is because the price of the activated carbon is very high because the activated carbon is used not only for producing activated carbon but also for many other purposes, and the price of the activated carbon itself produced by using the activated carbon is very high, which leads to the high price of the activated carbon on the market, and the price of the activated carbon produced by using urine as an activating agent is very low compared with the conventional production method.
Therefore, a method for preparing activated carbon by combining urine and biomass and performance analysis are imperative.
Disclosure of Invention
In order to solve the technical problems, the technical scheme provided by the invention is as follows: a method for preparing activated carbon by combining urine and biomass and performance analysis comprise the following steps:
s1, weighing 5g of crushed walnut shell raw material, putting the crushed walnut shell raw material into a beaker and a triangular conical flask, taking 4 parts, and respectively adding 28mL of urine (the mass ratio of the walnut shell to the urine is 10:1 and marked as WSU10:1), 55mL of urine (the mass ratio of the walnut shell to the urine is 5:1 and marked as WSU5:1), 138mL of urine (the mass ratio of the walnut shell to the urine is 2:1 and marked as WSU2:1) and 0mL of urine (the pure walnut shell is marked as WS);
s2, putting the solution prepared in the step S1 into a four-joint electric stirring water bath kettle for stirring for 48 hours;
s3, placing the solution stirred in the step S2 into a desk-top high-speed centrifuge for centrifugation, and removing a large amount of water to improve the efficiency of the oven;
s4, taking out the centrifuged sample in the step S3, putting the centrifuged sample into an electric heating blast oven, heating the sample from room temperature to 300 ℃, drying the sample for 14 hours, and removing most of water in the residual water;
s5, taking out the sample prepared in the step S4, putting the sample into a tube furnace, introducing N2 for protection, and rising the temperature from room temperature to 600 ℃ at 10 ℃ per min for 30 min;
s6, after the tube furnace is cooled, taking out samples from the tube furnace, drying and storing the prepared samples with 4 different urine feed ratios, and carrying out characterization and adsorption performance analysis research;
s7, characterization performance analysis of activated carbon: (1) surface functional group analysis is carried out by infrared spectroscopy, and a KBr tabletting method is adopted to mix a sample with KBr powder according to the ratio of 1:100, grinding the mixture in an agate mortar until a sample is completely mixed with KBr to form powder with uniform color, transferring the powder into a mold, pressing the powder into an approximately transparent round sheet by an oil press, carefully taking out the sheet and placing the sheet on a machine, emitting infrared rays with different frequencies by a Fourier infrared spectrometer to pass through a test sample, and analyzing the change of surface functions of different samples;
(2) analyzing by a scanning electron microscope;
(3) XRD analysis;
s8, analysis of adsorption performance of activated carbon: (1) after adsorption of methylene blue at WSU10:1, WSU5:1, WSU2:1, measuring the adsorption capacity in WS at different time, specifically:
first, 0.1g of WSU10 was weighed: 1. WSU5: 1. WSU2: 1. WS samples, respectively placed in different beakers, and corresponding letters are marked on the cup walls for distinction;
secondly, preparing a methylene blue solution with the concentration of 50g/ml for later use;
respectively adding 50ml of prepared methylene blue solution with the concentration of 50g/ml into different beakers;
fourthly, putting the magnetons into a container filled with the sample WSU10: 1. WSU5: 1. WSU2: 1. WS beaker, place on multi-head magnetic heating stirrer, turn on machine, and time rapidly;
fifthly, measuring the absorbance of the MB aqueous solution at intervals of 5min for the first two times, measuring the absorbance of the MB aqueous solution at intervals of 10min for the second two times, measuring the absorbance of the MB aqueous solution at intervals of 15min for the second two times, and measuring the absorbance of the MB aqueous solution at intervals of 30min for the last two times;
sixthly, recording data, analyzing and cleaning experimental equipment;
(2) when the adsorption is balanced (90min), the adsorption amounts of different concentrations in 4 samples with different urine feed ratios are measured, and the method specifically comprises the following steps:
first, 0.1g of WSU10 was weighed: 1. WSU5: 1. WSU2: 1. WS samples, respectively placed in different beakers, and corresponding letters are marked on the cup walls for distinction;
secondly, respectively taking prepared 50g/mL methylene blue solution, diluting the methylene blue solution into 40g/mL, 30g/mL, 20g/mL and 10g/mL, and adding 50mL into 4 beakers (WSU10:1, WSU5:1, WSU2:1 and WS);
thirdly, putting the magnetons into 4 beakers (WSU10:1, WSU5:1, WSU2:1 and WS), placing the beakers in a multi-head magnetic heating stirrer, turning on the machine and rapidly timing;
fourthly, measuring the absorbance of different beakers at 90 min;
recording data, analyzing and cleaning experimental equipment;
s8, establishing a data model for analysis: (1) the first-order kinetic analysis is used for describing the adsorption process with diffusion speed as a main factor, and the equation is as follows:
in the equation qeExpressed as activated carbon adsorption (mg/g); ceExpressed as solution concentration (mg/g); k1Expressed as the quasi-first order kinetic rate constant (min)-1)；qtExpressed as the amount of adsorbent per unit mass (mg/g) at t; when the adsorption process is coincidentWhen the first-level dynamic model is combined, the fitted curve is a straight line;
(2) two-stage kinetic analysis, describing the chemisorption rate, with the equation:
in the equation qeExpressed as activated carbon adsorption (mg/g); k2Expressed as the quasi-second order kinetic rate constant (g/mg-min); q. q.stExpressed as the adsorption capacity per unit mass of adsorbent (mg/g) K at t2Related to initial concentration of solute, pH, temperature and degree of agitation;
(3) establishing a Langmuir isothermal adsorption model, wherein when the surfaces of the adsorbents are the same, the adsorption process is monolayer adsorption (when the surfaces of the adsorbents are fully paved with monolayer adsorbate molecules, the adsorption quantity reaches the maximum value), the adsorption sites are the same, no interaction exists among the adsorbate molecules, each adsorption site only contains one adsorbate molecule, the maximum adsorption quantity of the adsorbents can be predicted, and the equation is as follows:
wherein q iseAs adsorbed amount (mg/g); ceAs solution concentration (mg/L); q. q.smSaturated adsorption capacity (related to the number of adsorption sites) for a monolayer of adsorbent; kLIs Langmuir equation constant (L/mg);
(4) establishing a Freundlich isothermal adsorption model, wherein the equation of the isothermal adsorption model is obtained by correcting a Langmuir equation, the non-monomolecular adsorption model is suitable for adsorption in low-concentration liquid, and the equation is as follows:
in the equation qeAs adsorbed amount (mg/g); ceAs solution concentration (mg/L); kFThe adsorption constant indicates the adsorption capacity (the higher the adsorption becomes easier); 1/n represents the adsorption strength.
Compared with the prior art, the invention has the advantages that: the urine is used as an activating agent to activate the biomass to prepare the activated carbon, so that the loss of instruments is reduced, the activated carbon is very environment-friendly and low in cost, the source of the activated carbon widely achieves the aim of treating wastes with wastes, the biomass such as walnut has great value in the aspects of environmental protection and resource recycling, the urine is used as an innovative activating agent, the urine and the activating agent provide cheaper biological basis for the preparation of the activated carbon, and the activated carbon is convenient to popularize.
As an improvement, in the scanning electron microscope analysis in the step S7, the biomass charcoal prepared from pure walnut shells under the same conditions has less surface pore structure and wrinkle shape, and the pore structure is non-uniform in distribution and has a smaller specific surface area; sample WSU10: compared with walnut shell raw material biomass activated carbon, the surface has more pore structures, and the size is even, the distribution is even, the shape is unified round hole pattern, its richer pore structure that owns is attributed to the urine as the activator, in the pyrolysis process, carbonization and activation take place simultaneously and react, urea forms macromolecular substance carbon nitride through thermal polycondensation, when further rising pyrolysis temperature, because the thermal instability performance of carbon nitride, the decomposition release forms the micromolecular gas, be favorable to the formation of walnut shell base biomass charcoal pore structure as the activated gas.
Drawings
FIG. 1 is a flow chart of a method for preparing activated carbon by combining urine and biomass and a nutshell activated carbon preparation flow chart for performance analysis.
FIG. 2 is a diagram of a MB solution standard curve for a method for preparing activated carbon by combining urine and biomass and performance analysis.
FIG. 3 is a schematic infrared spectrum of a method and performance analysis for producing activated carbon by combining urine and biomass.
Fig. 4 is a sample WSU10 of a method and performance analysis for making activated carbon by combining urine and biomass: 1 scanning electron microscope image.
FIG. 5 is an XRD pattern of four samples of a method for making activated carbon by combining urine and biomass and performance analysis.
FIG. 6 is a first order kinetic fit graph of a method and performance analysis for making activated carbon by combining urine and biomass.
FIG. 7 is a two-stage kinetic fit of a method and performance analysis for the production of activated carbon from a combination of urine and biomass.
FIG. 8 is a Langmuir isothermal adsorption model diagram of a method for preparing activated carbon by combining urine and biomass and performance analysis.
FIG. 9 is a Freundlich isothermal adsorption model diagram of a method for preparing activated carbon by combining urine and biomass and performance analysis.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
In specific implementation, the method for preparing the activated carbon by combining the urine and the biomass and performance analysis are characterized by comprising the following steps of:
s1, weighing 5g of crushed walnut shell raw material, putting the crushed walnut shell raw material into a beaker and a triangular conical flask, taking 4 parts, and respectively adding 28mL of urine (the mass ratio of the walnut shell to the urine is 10:1 and marked as WSU10:1), 55mL of urine (the mass ratio of the walnut shell to the urine is 5:1 and marked as WSU5:1), 138mL of urine (the mass ratio of the walnut shell to the urine is 2:1 and marked as WSU2:1) and 0mL of urine (the pure walnut shell is marked as WS);
s2, putting the solution prepared in the step S1 into a four-joint electric stirring water bath kettle for stirring for 48 hours;
s3, placing the solution stirred in the step S2 into a desk-top high-speed centrifuge for centrifugation, and removing a large amount of water to improve the efficiency of the oven;
s4, taking out the centrifuged sample in the step S3, putting the centrifuged sample into an electric heating blast oven, heating the sample from room temperature to 300 ℃, drying the sample for 14 hours, and removing most of water in the residual water;
s5, taking out the sample prepared in the step S4, putting the sample into a tube furnace, introducing N2 for protection, and rising the temperature from room temperature to 600 ℃ at 10 ℃ per min for 30 min;
s6, after the tube furnace is cooled, taking out samples from the tube furnace, drying and storing the prepared samples with 4 different urine feed ratios, and carrying out characterization and adsorption performance analysis research;
s7, characterization performance analysis of activated carbon: (1) surface functional group analysis is carried out by infrared spectroscopy, and a KBr tabletting method is adopted to mix a sample with KBr powder according to the ratio of 1:100, grinding the mixture in an agate mortar until a sample is completely mixed with KBr to form powder with uniform color, transferring the powder into a mold, pressing the powder into an approximately transparent round sheet by an oil press, carefully taking out the sheet and placing the sheet on a machine, emitting infrared rays with different frequencies by a Fourier infrared spectrometer to pass through a test sample, and analyzing the change of surface functions of different samples;
(2) analyzing by a scanning electron microscope;
(3) XRD analysis;
s8, analysis of adsorption performance of activated carbon: (1) after adsorption of methylene blue at WSU10:1, WSU5:1, WSU2:1, measuring the adsorption capacity in WS at different time, specifically:
first, 0.1g of WSU10 was weighed: 1. WSU5: 1. WSU2: 1. WS samples, respectively placed in different beakers, and corresponding letters are marked on the cup walls for distinction;
secondly, preparing a methylene blue solution with the concentration of 50g/ml for later use;
respectively adding 50ml of prepared methylene blue solution with the concentration of 50g/ml into different beakers;
fourthly, putting the magnetons into a container filled with the sample WSU10: 1. WSU5: 1. WSU2: 1. WS beaker, place on multi-head magnetic heating stirrer, turn on machine, and time rapidly;
fifthly, measuring the absorbance of the MB aqueous solution at intervals of 5min for the first two times, measuring the absorbance of the MB aqueous solution at intervals of 10min for the second two times, measuring the absorbance of the MB aqueous solution at intervals of 15min for the second two times, and measuring the absorbance of the MB aqueous solution at intervals of 30min for the last two times;
sixthly, recording data, analyzing and cleaning experimental equipment;
(2) when the adsorption is balanced (90min), the adsorption amounts of different concentrations in 4 samples with different urine feed ratios are measured, and the method specifically comprises the following steps:
first, 0.1g of WSU10 was weighed: 1. WSU5: 1. WSU2: 1. WS samples, respectively placed in different beakers, and corresponding letters are marked on the cup walls for distinction;
secondly, respectively taking prepared 50g/mL methylene blue solution, diluting the methylene blue solution into 40g/mL, 30g/mL, 20g/mL and 10g/mL, and adding 50mL into 4 beakers (WSU10:1, WSU5:1, WSU2:1 and WS);
thirdly, putting the magnetons into 4 beakers (WSU10:1, WSU5:1, WSU2:1 and WS), placing the beakers in a multi-head magnetic heating stirrer, turning on the machine and rapidly timing;
fourthly, measuring the absorbance of different beakers at 90 min;
recording data, analyzing and cleaning experimental equipment;
s8, establishing a data model for analysis: (1) the first-order kinetic analysis is used for describing the adsorption process with diffusion speed as a main factor, and the equation is as follows:
in the equation qeExpressed as activated carbon adsorption (mg/g); ceExpressed as solution concentration (mg/g); k1Expressed as the quasi-first order kinetic rate constant (min)-1)；qtExpressed as the amount of adsorbent per unit mass (mg/g) at t; when the adsorption process conforms to the quasi-first order kinetic model, the fitted curve is a straight line;
(2) two-stage kinetic analysis, describing the chemisorption rate, with the equation:
in the equation qeExpressed as activated carbon adsorption (mg/g); k2Expressed as the quasi-second order kinetic rate constant (g/mg-min); q. q.stExpressed as the adsorption capacity per unit mass of adsorbent (mg/g) K at t2Related to initial concentration of solute, pH, temperature and degree of agitation;
(3) establishing a Langmuir isothermal adsorption model, wherein when the surfaces of the adsorbents are the same, the adsorption process is monolayer adsorption (when the surfaces of the adsorbents are fully paved with monolayer adsorbate molecules, the adsorption quantity reaches the maximum value), the adsorption sites are the same, no interaction exists among the adsorbate molecules, each adsorption site only contains one adsorbate molecule, the maximum adsorption quantity of the adsorbents can be predicted, and the equation is as follows:
wherein qe is the amount adsorbed (mg/g); ceAs solution concentration (mg/L); q. q.smSaturated adsorption capacity (related to the number of adsorption sites) for a monolayer of adsorbent; kLIs Langmuir equation constant (L/mg);
(4) establishing a Freundlich isothermal adsorption model, wherein the equation of the isothermal adsorption model is obtained by correcting a Langmuir equation, the non-monomolecular adsorption model is suitable for adsorption in low-concentration liquid, and the equation is as follows:
in the equation qeAs adsorbed amount (mg/g); ceAs solution concentration (mg/L); kFThe adsorption constant indicates the adsorption capacity (the higher the adsorption becomes easier); 1/n represents the adsorption strength.
In the scanning electron microscope analysis in the step S7, the biomass charcoal prepared from pure walnut shells under the same conditions has less surface pore structure in a wrinkled shape, uneven pore structure distribution and smaller specific surface area; sample WSU10: compared with walnut shell raw material biomass activated carbon, the surface has more pore structures, and the size is even, the distribution is even, the shape is unified round hole pattern, its richer pore structure that owns is attributed to the urine as the activator, in the pyrolysis process, carbonization and activation take place simultaneously and react, urea forms macromolecular substance carbon nitride through thermal polycondensation, when further rising pyrolysis temperature, because the thermal instability performance of carbon nitride, the decomposition release forms the micromolecular gas, be favorable to the formation of walnut shell base biomass charcoal pore structure as the activated gas.
The working principle of the invention is as follows: firstly, (1) nitrogen is doped, and carbon materials are doped and modified by a nitrogen-containing solution (mixed and stirred in the nitrogen-containing solution), so that the carbon materials have the properties of activated carbon and also have unique electronic conductivity and catalytic performance. The introduced N atoms increase active sites on the surface of the nitrogen-doped carbon material, so that the adsorption effect is enhanced.
(2) The thermal conversion of the N element in the urine and the formation of carbon nitride are the root causes of the urine to be an activator. The method is characterized in that a nitrogen-containing compound in urine is combined with carbon element in walnut shells at 520 ℃ to obtain carbon nitride, and the carbon nitride starts to decompose and release gas at 600 ℃ to leave holes, so that the effect of 'punching' is achieved.
The urine is used as an activator, so that the corrosion of strong acid, strong alkali and oxidizing salt to instruments and the damage to the environment of the traditional activator are avoided, nitrogen-doped carbon structures can be generated by the combination of nitrogen-containing compounds in the urine and C elements in walnut shells, and holes are further formed by gas released by the nitrogen-containing compounds through heat treatment. Therefore, the walnut kernel is ground and fully stirred in the experiment, and is mixed with urine to achieve the pre-activation effect.
The sample can be formed into a crack-type carbon structure body through carbonization, volatile gas substances (part of nitrogen-containing compounds are volatilized) are removed, so that a gap is formed, the optimal carbonization condition is obtained in Wangdi research that the sample stays for 30min at 600 ℃, and the adsorption effect is better for preparing the crushed activated carbon at a lower activation temperature. Because the urine is used for activation, the effect of preactivation is already achieved in the mixing process of the walnut shell powder and the urine, and the effect of activation is achieved again in the high-temperature carbonization process, so that the carbonization and activation of the experiment can be synchronously carried out, and the reaction is carried out in a tubular furnace at the temperature of 600 ℃ for about 30 min.
(3) Definition and kind of adsorption of activated carbon material
Adsorption refers to the phenomenon that molecules, atoms or ions can automatically attach to the surface of a solid under certain conditions. Adsorption can be divided into physical adsorption and chemical adsorption. The physical adsorption is adsorption generated by intermolecular force between the adsorbent and the adsorbate, and can be adsorbed at low temperature, but substances which are originally adsorbed into the activated carbon leave the activated carbon along with the increase of the temperature, namely desorption. Chemisorption is the action of chemical bonds between the adsorbent and the adsorbate (reacting with the substance on the activated carbon, and the new substance generated by the substance and the substance is retained on the activated carbon), and the reaction process is selective (the substance A only reacts with the substance B, and does not react with the substance C, namely the adsorption effect on the substance B is independent of the substance C, and the universal adsorption speed cannot be obtained).
In the adsorption process, physical adsorption and chemical adsorption occur simultaneously, and adsorbates on the surface of the adsorbent are accumulated to reduce the adsorption effect of the adsorbates (chemical: the surface of the activated carbon is surrounded by the substance C, even if the substance B is outside, the substance B cannot react with the substance C, physical: the substance C is surrounded by the substance C, if the substance B is outside, the intermolecular force for adsorbing the substance B is smaller than that for adsorbing the substance C, so that the substance B is easy to leave the activated carbon, and further the substance B is shown as poor in adsorption effect) [7] main adsorption types can be known through an adsorption kinetic model, and further the adsorption temperature and the adsorption concentration which are suitable for the activated carbon, namely the concentration ratio of the activated carbon to the adsorbed substances, are known according to the.
(4) Adsorption kinetics model
In order to predict the adsorption process, the adsorption mechanism needs to be analyzed through an adsorption kinetic model. The change curve of the adsorption amount and the time can be used for representing the reaction process of adsorption, so that the optimal distribution ratio between the adsorbent and the solution can be obtained, the time required for balancing is reached, and the change rule of the adsorption rate is obtained. The adsorption mechanism can be predicted by using different adsorption kinetic models, and the experiment uses a quasi-first-stage kinetic model and a quasi-second-stage kinetic model
A first order kinetic model
The quasi-first order kinetic model is used to describe the adsorption process where diffusion velocity is the dominant factor.
In the equation qeExpressed as activated carbon adsorption (mg/g); ceExpressed as solution concentration (mg/g); k1Expressed as the quasi-first order kinetic rate constant (min)-1)；qtExpressed as the amount of adsorption per unit mass of adsorbent (mg/g) at t
When the adsorption process conforms to the quasi-first order kinetic model, the fitted curve should be a straight line.
Fitting: connecting multiple points on a plane by a smooth curve with specific meaning, and using the fitted curve to represent different functions with different names and different meanings
B quasi-second-order kinetic model
Quasi-second order kinetic models are widely used to describe chemisorption rates
In the equation qeExpressed as activated carbon adsorption (mg/g); k2Expressed as the quasi-second order kinetic rate constant (g/mg-min); q. q.stExpressed as the adsorption capacity per unit mass of adsorbent (mg/g) K at t2Related to the initial concentration of solute, pH, temperature and degree of agitation.
(5) Adsorption isotherm
Langmuir isothermal adsorption model
The Langmuir isothermal adsorption model assumes that the adsorbent surfaces are the same, the adsorption process is monolayer adsorption (when the adsorbent surfaces are fully paved with monolayer adsorbate molecules, the adsorption amount reaches the maximum value), the adsorption sites are the same, no interaction exists among the adsorbate molecules, and each adsorption site only contains one adsorbate molecule. The maximum adsorption amount of the adsorbent can be predicted.
The Langmuir isothermal adsorption model adsorption equation is:
wherein q iseAs adsorbed amount (mg/g); ceAs solution concentration (mg/L); qm is the saturated adsorption capacity of the monomolecular layer of the adsorbent (related to the number of adsorption sites); kLIs the Langmuir equation constant (L/mg)
Freundlich isothermal adsorption model
The Freundlich isothermal adsorption model is obtained by correcting the Langmuir equation, and the non-monomolecular adsorption model is suitable for adsorption in low-concentration liquid.
Q in the formulaeAs adsorbed amount (mg/g); ceAs solution concentration (mg/L); kFThe adsorption constant indicates the adsorption capacity (the higher the adsorption becomes easier); 1/n represents adsorption strength
Second, the experimental materials and the equipment are shown in table 1 and table 2:
TABLE 1 Main test materials
TABLE 2 Main instruments
Preparation of active carbon
(1) Weighing 5g of crushed walnut shell raw material, putting the crushed walnut shell raw material into a beaker and a triangular conical flask, taking 4 parts, and respectively adding 28mL of urine (the mass ratio of the walnut shell to the urine is 10:1 and marked as WSU10:1), 55mL of urine (the mass ratio of the walnut shell to the urine is 5:1 and marked as WSU5:1), 138mL of urine (the mass ratio of the walnut shell to the urine is 2:1 and marked as WSU2:1) and 0mL of urine (the pure walnut shell is marked as WS);
(3) putting the prepared solution into a four-joint electric stirring water bath kettle for stirring for 48 hours;
(4) placing the stirred solution into a table-type high-speed centrifuge for centrifugation, and removing a large amount of water to improve the efficiency of the oven;
(5) taking out the centrifuged sample, putting the centrifuged sample into an electric heating blast oven, heating the sample to 300 ℃ from room temperature, drying the sample for 14 hours, and removing most of water in the residual water;
(6) taking out the sample, placing in a tube furnace, introducing N2 for protection, increasing temperature from room temperature to 600 deg.C at 10 deg.C per min for 30min
(7) After the tubular furnace is cooled, taking out a sample from the tubular furnace, and drying and storing the prepared samples with four different urine feed ratios for characterization and absorption performance analysis and research;
drawing of tetra-methylene blue Standard (MB) Curve
The wavelength of the maximum light absorption value at a concentration of 50g/mL among all the wavelengths was measured by a spectrophotometer, and the light absorption value was the largest among the wavelengths at 665nm, so that the light absorption value of the sample at 655nm was selected. A50 g/mL solution of demethylated blue was selected, diluted 10-fold into one set, and 5 sets of data (including undiluted portions) were made, and the absorbance values thereof were recorded separately and plotted as shown in FIG. 2.
Fifth, characterization analysis result of activated carbon
1. Characterization and analysis results of activated carbon
1.1 Infrared spectroscopic analysis-surface functional group analysis
The variation of the surface function of different samples was analyzed by transmitting infrared light of different frequencies through the test sample by means of a fourier infrared spectrometer. Using KBr tabletting method, the sample was mixed with KBr powder according to 1:100, ground in an agate mortar until the sample was completely mixed with KBr to a uniform color powder, transferred to a mold and pressed by oil press to a nearly transparent round sheet, carefully removed and placed on the machine.
As shown in fig. 3, WS, WSU10:1, WSU5:1, WSU2:1 has a large absorption peak at 3835-2965cm-1 at the wavelength of 500-4000cm-1, which is caused by tensile vibration of hydroxyl groups in the carbon-containing organic matter and-O-H in the bound water, and the-OH content in the carbon material is increased along with the increase of the urine content. And the stretching vibration with-N-H, the stretching vibration of carbonyl at 1740-1524cm-1 is an absorption vibration area of oxygen-containing functional groups, which shows that the surface of the walnut shell biomass carbon material possibly contains oxygen-containing functional groups with C-O-C, -COO-and the like, and the peak at 1057-713cm-1 shows that the material has-CH functional groups, and the chemical functional groups enable the material to have stronger adsorption capacity. As can be seen from the figure, the shapes of the infrared spectrograms of different samples are not obviously changed, which shows that the surface property of the biomass charcoal material is not changed by increasing the urea content.
1.2 scanning Electron microscopy analysis
To further explore sample WSU10:1, SEM analysis, the results are shown in FIG. 4. As can be seen from fig. 4, the biomass charcoal prepared from pure walnut shells under the same conditions has less surface pore structure and wrinkle shape, and the pore structure is not uniformly distributed and has smaller specific surface area. Compared with walnut shell raw material biomass activated carbon, sample WSU10:1, the surface has more pore structures, and the pore structures have uniform size, uniform distribution and uniform shape. The surface presents more platelet-like structures, providing a greater specific surface area. The abundant pore structure and more specific surface area are beneficial to provide more active binding sites. Sample WSU10:1 has a rich pore structure, mainly due to the fact that urine is used as an activator, carbonization and activation are simultaneously carried out in the pyrolysis process, urea forms high molecular substance carbon nitride through thermal polycondensation, when the pyrolysis temperature is further increased, due to the thermal instability of the carbon nitride, the carbon nitride is decomposed and released to form small molecular gases, such as CO2, NH3 and the like, and the activated gas is used for facilitating the formation of the pore structure of the walnut shell-based biomass carbon.
1.3, XRD analysis
As shown in FIG. 5, 4 XRD patterns are sequentially WSU-2: 1, WSU-5: 1, WSU10: WS in WS, with two higher peaks of similar height at 20.58 ° and 27.64 ° and a highest peak at 26.44 °, respectively. At WSU10:1, the highest peak at 26.46 °, the higher peaks at 23.84 ° and 20.76 ° and the distinct diffraction peaks at 50 °, 68.16 °, 81.42 °. In WSU-5: 1, the highest peak at 26.4 ° and the higher peaks at 20.66 ° and 27.68 °. In WSU-2: 1, has a highest peak at 26.46 deg., a higher peak at 27.62 deg., and a higher peak at 26.92 deg. °
In conclusion, WSU10: the maximum number of peaks in 1, indicating that the activated carbon has the most crystalline structure, and among the broad peaks ranging from 18 ° to 30 °, WSU10: the highest peak in 1 indicates the highest crystallinity. Therefore, the urine has obvious effect on the characteristic microcrystalline structure of the activated carbon formed by the activation of the walnut shells. And WSU10:1, the crystallization effect is best, and the crystal substance is better.
Sixthly, analysis results of adsorption performance of activated carbon
1. Activated carbon adsorption of methylene blue
At WSU10:1, WSU5:1, WSU2:1, determination of the amount of adsorption in WS at different times
(1) 0.1g of sample WSU10 was weighed: 1, WSU5:1, WSU2:1, WS, respectively putting into different beakers, and marking corresponding letters on the cup walls for distinguishing;
(2) preparing 50g/ml methylene blue solution for later use;
(3) respectively adding 50ml of prepared methylene blue solution with the concentration of 50g/ml into different beakers;
(4) put magnetons into WSU10:1, WSU5:1, WSU2:1, WS beaker, place on multi-head magnetic heating stirrer, turn on machine, and time rapidly;
(5) measuring the absorbance of the MB aqueous solution at intervals of 5min in the first two times, measuring the absorbance of the MB aqueous solution at intervals of 10min in the second two times, measuring the absorbance of the MB aqueous solution at intervals of 15min in the second two times, and measuring the absorbance of the MB aqueous solution at intervals of 30min, 5min, 10min, 20min, 30min, 45min, 60min and 90min in the last two times;
(6) data were recorded, and experimental equipment was analyzed and cleaned.
2. At adsorption equilibrium (90min) WSU10:1, WSU5:1, WSU2:1, WS, determination of adsorption amount of different concentrations in activated carbon of urine dosage ratio:
(1) 0.1g of sample WSU10 was weighed: 1, WSU5:1, WSU2:1, WS, respectively putting into different beakers, and marking corresponding letters on the cup walls for distinguishing;
(2) the prepared methylene blue solution with the concentration of 50g/mL is respectively diluted to 40g/mL, 30g/mL, 20g/mL and 10g/mL, and 50mL is added into a different beaker WSU10:1, WSU5:1, WSU2:1, WS;
(3) put magnetons into WSU10:1, WSU5:1, WSU2:1, WS beaker, place on multi-head magnetic heating stirrer, turn on machine, and time rapidly;
(4) measuring the absorbance of different beakers at 90 min;
(5) data were recorded, and experimental equipment was analyzed and cleaned.
Seven, data model analysis
1. Kinetic analysis
1.1 first order kinetics
Under experimental conditions, adsorption of MB by biomass charcoal is a fast-then-slow kinetic process, and WSU10:1, WSU5:1, WSU2:1, WS are all in equilibrium, R20.52739-0.95522, the correlation is not high, which shows that the matching degree of the walnut shell activated carbon adsorption MB process and the first-order kinetic model fitting is not high, as shown in FIG. 6;
1.2, secondary kinetics, as shown in fig. 7.
Under experimental conditions, the adsorption of the biomass charcoal to the methylene blue is a fast-front slow dynamic process, and the adsorption time of the biomass charcoal to the methylene blue is 1h, and the adsorption time of the biomass charcoal to the methylene blue is WSU10:1, WSU5:1, WSU2:1, WS samples all reached equilibrium, R20.78966 to 0.9717, the higher order of correlation indicates that the process is dominated by chemisorption [7]]But because of the first and second levels of R2None of them reach a significant level of correlation (above 0.99) so the adsorption process cannot be dominated by chemisorption, which is comprised by physisorption and the chemisorption ratio is slightly higher than physisorption.
As can be seen from FIGS. 6 and 7, the fitting results of both equations illustrate WSU-10: 1 has the best adsorption effect on MB and has the fastest speed.
1.3 adsorption isotherm model
The adsorption and desorption reach the equilibrium with the time, and when the activated carbon and the wastewater reach the adsorption equilibrium at a certain temperature, the relation curve of the maximum adsorption amount of the activated carbon changing along with the concentration of the adsorbate in the solution is called an adsorption isotherm. The properties of the adsorbent (activated carbon), the maximum adsorption amount, and the like can be reflected according to the adsorption isotherm calculation. There are many adsorption isotherm models, and the experiment is analyzed by adopting a Langmuir isothermal adsorption model and a Freundlich isothermal adsorption model.
Langmuir model fitting results: r2From 0.822 to 0.985, results of Freundlich model fitting: r20.822 to 0.991, and the Langmuir correlation is higher, and the surface active carbon adsorption model is mainly a non-uniform surface adsorption model. From fig. 8 and 9, it can be seen that the equilibrium adsorption amounts of the four samples all increase and then approach to equilibrium with the increase of the MB concentration, and the WSU-10: 1 is particularly evident, WSU-2: 1 is then approximately in a straight line. WSU-10 can be obtained based on the equation of isotherm: 1, the adsorption capacity is the largest, the adsorption effect is the best, qmax22.37mg/g, which is the same as the conclusion from the adsorption kinetics equation.
Comprehensive analysis, due to WSU-10: 1, and has a rich pore structure, which indicates that different proportions of urine do have an influence on the activation of walnut shells, and proper proportions are critical, and poor proportions such as WSU-2: 1 is even less effective than WS because of the large size of the pores formed due to the excessive urine content, which is not good for adsorption and the poor crystallization effect.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature, and in the description of the invention, "plurality" means two or more unless explicitly specifically defined otherwise.
In the present invention, unless otherwise specifically stated or limited, the terms "mounted," "connected," "fixed," and the like are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly above and obliquely above the second feature, or simply meaning that the first feature is at a lesser level than the second feature.
In the description herein, reference to the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" or the like means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made in the above embodiments by those of ordinary skill in the art without departing from the principle and spirit of the present invention.
Claims (2)
1. A method for preparing activated carbon by combining urine and biomass and performance analysis are characterized by comprising the following steps:
s1, weighing 5g of crushed walnut shell raw material, putting the crushed walnut shell raw material into a beaker and a triangular conical flask, taking 4 parts, and respectively adding 28mL of urine (the mass ratio of the walnut shell to the urine is 10:1 and marked as WSU10:1), 55mL of urine (the mass ratio of the walnut shell to the urine is 5:1 and marked as WSU5:1), 138mL of urine (the mass ratio of the walnut shell to the urine is 2:1 and marked as WSU2:1) and 0mL of urine (the pure walnut shell is marked as WS);
s2, putting the solution prepared in the step S1 into a four-joint electric stirring water bath kettle for stirring for 48 hours;
s3, placing the solution stirred in the step S2 into a desk-top high-speed centrifuge for centrifugation, and removing a large amount of water to improve the efficiency of the oven;
s4, taking out the centrifuged sample in the step S3, putting the centrifuged sample into an electric heating blast oven, heating the sample from room temperature to 300 ℃, drying the sample for 14 hours, and removing most of water in the residual water;
s5, taking out the sample prepared in the step S4, putting the sample into a tube furnace, introducing N2 for protection, and rising the temperature from room temperature to 600 ℃ at 10 ℃ per min for 30 min;
s6, after the tube furnace is cooled, taking out samples from the tube furnace, drying and storing the prepared samples with 4 different urine feed ratios, and carrying out characterization and adsorption performance analysis research;
s7, characterization performance analysis of activated carbon: (1) analyzing surface functional groups by utilizing infrared spectroscopy, mixing a sample and KBr powder according to a ratio of 1:100 by adopting a KBr tabletting method, grinding the mixture in an agate mortar until the sample is completely mixed with KBr to form powder with uniform color, transferring the powder into a die, pressing the powder into an approximately transparent round sheet by an oil press, carefully taking out the powder and placing the powder in a machine, emitting infrared rays with different frequencies by a Fourier infrared spectrometer to pass through a test sample, and analyzing the change of the surface functional groups of different samples;
(2) analyzing by a scanning electron microscope;
(3) XRD analysis;
s8, analysis of adsorption performance of activated carbon: (1) measuring the adsorption amount of methylene blue in WSU10:1, WSU5:1, WSU2:1 and WS at different times after the methylene blue is adsorbed, and specifically:
firstly, weighing 0.1g of WSU10:1, WSU5:1, WSU2:1 and WS samples, respectively placing the samples into different beakers, and marking corresponding letters on the cup walls for distinguishing;
secondly, preparing a methylene blue solution with the concentration of 50g/ml for later use;
respectively adding 50ml of prepared methylene blue solution with the concentration of 50g/ml into different beakers;
fourthly, putting the magnetons into a beaker filled with samples WSU10:1, WSU5:1, WSU2:1 and WS, placing the beaker in a multi-head magnetic heating stirrer, turning on the machine and rapidly timing;
fifthly, measuring the absorbance of the MB aqueous solution at intervals of 5min for the first two times, measuring the absorbance of the MB aqueous solution at intervals of 10min for the second two times, measuring the absorbance of the MB aqueous solution at intervals of 15min for the second two times, and measuring the absorbance of the MB aqueous solution at intervals of 30min for the last two times;
sixthly, recording data, analyzing and cleaning experimental equipment;
(2) when the adsorption is balanced (90min), the adsorption amounts of different concentrations in 4 samples with different urine feed ratios are measured, and the method specifically comprises the following steps:
firstly, weighing 0.1g of WSU10:1, WSU5:1, WSU2:1 and WS samples, respectively placing the samples into different beakers, and marking corresponding letters on the cup walls for distinguishing;
secondly, respectively taking prepared 50g/mL methylene blue solution, diluting the methylene blue solution into 40g/mL, 30g/mL, 20g/mL and 10g/mL, and adding 50mL into 4 beakers (WSU10:1, WSU5:1, WSU2:1 and WS);
thirdly, putting the magnetons into 4 beakers (WSU10:1, WSU5:1, WSU2:1 and WS), placing the beakers in a multi-head magnetic heating stirrer, turning on the machine and rapidly timing;
fourthly, measuring the absorbance of different beakers at 90 min;
recording data, analyzing and cleaning experimental equipment;
s8, establishing a data model for analysis: (1) the first-order kinetic analysis is used for describing the adsorption process with diffusion speed as a main factor, and the equation is as follows:
in the equation qeExpressed as activated carbon adsorption (mg/g); ceExpressed as solution concentration (mg/g); k1Expressed as the quasi-first order kinetic rate constant (min)-1)；qtExpressed as the amount of adsorbent per unit mass (mg/g) at t; when the adsorption process conforms to the quasi-first order kinetic model, the fitted curve is a straight line;
(2) two-stage kinetic analysis, describing the chemisorption rate, with the equation:
in the equation qeExpressed as activated carbon adsorption (mg/g); k2Expressed as the quasi-second order kinetic rate constant (g/mg-min); q. q.stExpressed as the adsorption capacity per unit mass of adsorbent (mg/g) K at t2Related to initial concentration of solute, pH, temperature and degree of agitation;
(3) establishing a Langmuir isothermal adsorption model, wherein when the surfaces of the adsorbents are the same, the adsorption process is monolayer adsorption (when the surfaces of the adsorbents are fully paved with monolayer adsorbate molecules, the adsorption quantity reaches the maximum value), the adsorption sites are the same, no interaction exists among the adsorbate molecules, each adsorption site only contains one adsorbate molecule, the maximum adsorption quantity of the adsorbents can be predicted, and the equation is as follows:
wherein q iseAs adsorbed amount (mg/g); ceAs solution concentration (mg/L); q. q.smSaturated adsorption capacity (related to the number of adsorption sites) for a monolayer of adsorbent; kLIs Langmuir equation constant (L/mg);
(4) establishing a Freundlich isothermal adsorption model, wherein the equation of the isothermal adsorption model is obtained by correcting a Langmuir equation, the non-monomolecular adsorption model is suitable for adsorption in low-concentration liquid, and the equation is as follows:
in the equation qeAs adsorbed amount (mg/g); ceAs solution concentration (mg/L); kFThe adsorption constant indicates the adsorption capacity (the higher the adsorption becomes easier); 1/n represents the adsorption strength.
2. The method for preparing activated carbon by combining urine and biomass and the performance analysis thereof according to claim 1 are characterized in that: in the scanning electron microscope analysis in the step S7, the biomass charcoal prepared from pure walnut shells under the same conditions has less surface pore structure in a wrinkled shape, uneven pore structure distribution and smaller specific surface area; sample WSU10: compared with walnut shell raw material biomass activated carbon, the surface has more pore structures, and the size is even, the distribution is even, the shape is unified round hole pattern, its richer pore structure that owns is attributed to the urine as the activator, in the pyrolysis process, carbonization and activation take place simultaneously and react, urea forms macromolecular substance carbon nitride through thermal polycondensation, when further rising pyrolysis temperature, because the thermal instability performance of carbon nitride, the decomposition release forms the micromolecular gas, be favorable to the formation of walnut shell base biomass charcoal pore structure as the activated gas.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011568266.8A CN112551525A (en) | 2020-12-26 | 2020-12-26 | Method for preparing activated carbon by combining urine and biomass and performance analysis |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011568266.8A CN112551525A (en) | 2020-12-26 | 2020-12-26 | Method for preparing activated carbon by combining urine and biomass and performance analysis |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112551525A true CN112551525A (en) | 2021-03-26 |
Family
ID=75033152
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011568266.8A Withdrawn CN112551525A (en) | 2020-12-26 | 2020-12-26 | Method for preparing activated carbon by combining urine and biomass and performance analysis |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112551525A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113604511A (en) * | 2021-08-06 | 2021-11-05 | 东北农业大学 | Method for harmless and recycling treatment of rural organic garbage |
| CN113754002A (en) * | 2021-07-29 | 2021-12-07 | 浙江大学 | Urine cascade treatment system based on agriculture and forestry waste source active carbon |
-
2020
- 2020-12-26 CN CN202011568266.8A patent/CN112551525A/en not_active Withdrawn
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113754002A (en) * | 2021-07-29 | 2021-12-07 | 浙江大学 | Urine cascade treatment system based on agriculture and forestry waste source active carbon |
| WO2023004993A1 (en) * | 2021-07-29 | 2023-02-02 | 浙江大学 | Urine cascade processing system based on agriculture and forest waste-sourced activated carbon |
| CN113604511A (en) * | 2021-08-06 | 2021-11-05 | 东北农业大学 | Method for harmless and recycling treatment of rural organic garbage |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Mu et al. | NaOH-modified mesoporous biochar derived from tea residue for methylene Blue and Orange II removal | |
| Yin et al. | Biochar produced from the co-pyrolysis of sewage sludge and walnut shell for ammonium and phosphate adsorption from water | |
| Chen et al. | Adsorption removal of pollutant dyes in wastewater by nitrogen-doped porous carbons derived from natural leaves | |
| Zheng et al. | Insight into the KOH/KMnO4 activation mechanism of oxygen-enriched hierarchical porous biochar derived from biomass waste by in-situ pyrolysis for methylene blue enhanced adsorption | |
| Aghel et al. | CO2 capture from biogas by biomass-based adsorbents: A review | |
| Ahmedna et al. | Surface properties of granular activated carbons from agricultural by-products and their effects on raw sugar decolorization | |
| Qian et al. | Preparation of activated carbons from cattle-manure compost by zinc chloride activation | |
| Cabal et al. | Adsorption of naphthalene from aqueous solution on activated carbons obtained from bean pods | |
| CN109809403B (en) | Preparation method and application of biogas residue-based activated carbon with high adsorption performance | |
| Xu et al. | Aquatic plant-derived biochars produced in different pyrolytic conditions: spectroscopic studies and adsorption behavior of diclofenac sodium in water media | |
| Tran et al. | A sustainable, low-cost carbonaceous hydrochar adsorbent for methylene blue adsorption derived from corncobs | |
| CN112551525A (en) | Method for preparing activated carbon by combining urine and biomass and performance analysis | |
| Qian et al. | A delicate method for the synthesis of high-efficiency Hg (II) The adsorbents based on biochar from corn straw biogas residue | |
| CN101612554A (en) | The preparation method of conducting polymer modified active carbon | |
| Kang et al. | Adsorption of basic dyes using walnut shell-based biochar produced by hydrothermal carbonization | |
| Kong et al. | Physico-chemical characteristics and the adsorption of ammonium of biochar pyrolyzed from distilled spirit lees, tobacco fine and Chinese medicine residues | |
| Lee et al. | Effect of pretreatment conditions on the chemical–structural characteristics of coconut and palm kernel shell: A potentially valuable precursor for eco-efficient activated carbon production | |
| Wei et al. | Adsorption of phenol from aqueous solution on activated carbons prepared from antibiotic mycelial residues and traditional biomass | |
| CN110683540A (en) | Nitrogen-rich hierarchical pore biomass charcoal and application thereof | |
| CN114797766A (en) | Porous biochar and preparation method and application thereof | |
| López-Velandia et al. | Adsorption of volatile carboxylic acids on activated carbon synthesized from watermelon shells | |
| Arslanoğlu et al. | Fabrication, characterization, and adsorption applications of low-cost hybride activated carbons from peanut shell-vinasse mixtures by one-step pyrolysis | |
| Liu et al. | Biochar derived from chicken manure as a green adsorbent for naphthalene removal | |
| Chen et al. | An effective pre-burning treatment boosting adsorption capacity of sorghum distillers' grain derived porous carbon | |
| Xia et al. | Fungal mycelium modified hierarchical porous carbon with enhanced performance and its application for removal of organic pollutants |
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 | ||
| WW01 | Invention patent application withdrawn after publication | ||
| WW01 | Invention patent application withdrawn after publication |
Application publication date: 20210326 |