CN117001796B - Super-hydrophobic wood with demulsification capability and preparation method and application thereof - Google Patents
Super-hydrophobic wood with demulsification capability and preparation method and application thereof Download PDFInfo
- Publication number
- CN117001796B CN117001796B CN202310802965.1A CN202310802965A CN117001796B CN 117001796 B CN117001796 B CN 117001796B CN 202310802965 A CN202310802965 A CN 202310802965A CN 117001796 B CN117001796 B CN 117001796B
- Authority
- CN
- China
- Prior art keywords
- wood
- super
- hydrophobic
- demulsification
- solution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000002023 wood Substances 0.000 title claims abstract description 180
- 230000003075 superhydrophobic effect Effects 0.000 title claims abstract description 94
- 238000002360 preparation method Methods 0.000 title claims abstract description 12
- 238000000926 separation method Methods 0.000 claims abstract description 84
- 239000000839 emulsion Substances 0.000 claims abstract description 36
- 239000010779 crude oil Substances 0.000 claims abstract description 32
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 45
- -1 polydimethylsiloxane Polymers 0.000 claims description 45
- 229910021393 carbon nanotube Inorganic materials 0.000 claims description 44
- 239000002041 carbon nanotube Substances 0.000 claims description 44
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 42
- 229920002873 Polyethylenimine Polymers 0.000 claims description 37
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 claims description 29
- 238000000034 method Methods 0.000 claims description 29
- 239000004205 dimethyl polysiloxane Substances 0.000 claims description 25
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 claims description 25
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 22
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 22
- 238000011068 loading method Methods 0.000 claims description 22
- 229910017604 nitric acid Inorganic materials 0.000 claims description 22
- QAOWNCQODCNURD-UHFFFAOYSA-N sulfuric acid Substances OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 22
- 235000019476 oil-water mixture Nutrition 0.000 claims description 15
- 239000005708 Sodium hypochlorite Substances 0.000 claims description 14
- 230000004048 modification Effects 0.000 claims description 14
- 238000012986 modification Methods 0.000 claims description 14
- 230000008569 process Effects 0.000 claims description 14
- SUKJFIGYRHOWBL-UHFFFAOYSA-N sodium hypochlorite Chemical compound [Na+].Cl[O-] SUKJFIGYRHOWBL-UHFFFAOYSA-N 0.000 claims description 14
- 230000002209 hydrophobic effect Effects 0.000 claims description 13
- 238000010438 heat treatment Methods 0.000 claims description 12
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 10
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 claims description 6
- 238000001035 drying Methods 0.000 claims description 6
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 claims description 6
- 239000002904 solvent Substances 0.000 claims description 6
- 238000003756 stirring Methods 0.000 claims description 6
- 239000003795 chemical substances by application Substances 0.000 claims description 4
- 229910052739 hydrogen Inorganic materials 0.000 claims description 4
- 239000001257 hydrogen Substances 0.000 claims description 4
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 claims description 3
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 claims description 3
- 239000011248 coating agent Substances 0.000 claims description 2
- 238000000576 coating method Methods 0.000 claims description 2
- 238000004108 freeze drying Methods 0.000 claims description 2
- 239000011148 porous material Substances 0.000 claims description 2
- 238000002156 mixing Methods 0.000 claims 1
- 239000007762 w/o emulsion Substances 0.000 abstract description 42
- 230000000694 effects Effects 0.000 abstract description 29
- 239000000463 material Substances 0.000 abstract description 16
- 238000012360 testing method Methods 0.000 description 32
- 238000002474 experimental method Methods 0.000 description 29
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 22
- 239000003921 oil Substances 0.000 description 20
- 235000019198 oils Nutrition 0.000 description 19
- 238000001179 sorption measurement Methods 0.000 description 17
- 229920002488 Hemicellulose Polymers 0.000 description 12
- 229920005610 lignin Polymers 0.000 description 12
- 238000005259 measurement Methods 0.000 description 10
- 230000009471 action Effects 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 5
- 239000004094 surface-active agent Substances 0.000 description 5
- 230000005591 charge neutralization Effects 0.000 description 4
- 239000003344 environmental pollutant Substances 0.000 description 4
- 230000002572 peristaltic effect Effects 0.000 description 4
- 231100000719 pollutant Toxicity 0.000 description 4
- 238000011084 recovery Methods 0.000 description 4
- 238000001612 separation test Methods 0.000 description 4
- 125000003277 amino group Chemical group 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 239000007764 o/w emulsion Substances 0.000 description 3
- 238000002791 soaking Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- NWGKJDSIEKMTRX-AAZCQSIUSA-N Sorbitan monooleate Chemical compound CCCCCCCC\C=C/CCCCCCCC(=O)OC[C@@H](O)[C@H]1OC[C@H](O)[C@H]1O NWGKJDSIEKMTRX-AAZCQSIUSA-N 0.000 description 2
- 239000006229 carbon black Substances 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 238000005485 electric heating Methods 0.000 description 2
- 238000002329 infrared spectrum Methods 0.000 description 2
- 238000001000 micrograph Methods 0.000 description 2
- 229910021392 nanocarbon Inorganic materials 0.000 description 2
- 238000000879 optical micrograph Methods 0.000 description 2
- 230000002195 synergetic effect Effects 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- RNFJDJUURJAICM-UHFFFAOYSA-N 2,2,4,4,6,6-hexaphenoxy-1,3,5-triaza-2$l^{5},4$l^{5},6$l^{5}-triphosphacyclohexa-1,3,5-triene Chemical compound N=1P(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP=1(OC=1C=CC=CC=1)OC1=CC=CC=C1 RNFJDJUURJAICM-UHFFFAOYSA-N 0.000 description 1
- 241000872198 Serjania polyphylla Species 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009529 body temperature measurement Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 229910021419 crystalline silicon Inorganic materials 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 239000003995 emulsifying agent Substances 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 239000003063 flame retardant Substances 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 238000011081 inoculation Methods 0.000 description 1
- 239000008204 material by function Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- CMQCNTNASCDNGR-UHFFFAOYSA-N toluene;hydrate Chemical compound O.CC1=CC=CC=C1 CMQCNTNASCDNGR-UHFFFAOYSA-N 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 239000002569 water oil cream Substances 0.000 description 1
- 238000009736 wetting Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
- B27K3/00—Impregnating wood, e.g. impregnation pretreatment, for example puncturing; Wood impregnation aids not directly involved in the impregnation process
- B27K3/02—Processes; Apparatus
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D17/00—Separation of liquids, not provided for elsewhere, e.g. by thermal diffusion
- B01D17/02—Separation of non-miscible liquids
- B01D17/0202—Separation of non-miscible liquids by ab- or adsorption
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
- B27K3/00—Impregnating wood, e.g. impregnation pretreatment, for example puncturing; Wood impregnation aids not directly involved in the impregnation process
- B27K3/02—Processes; Apparatus
- B27K3/15—Impregnating involving polymerisation including use of polymer-containing impregnating agents
- B27K3/153—Without in-situ polymerisation, condensation, or cross-linking reactions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
- B27K3/00—Impregnating wood, e.g. impregnation pretreatment, for example puncturing; Wood impregnation aids not directly involved in the impregnation process
- B27K3/16—Inorganic impregnating agents
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
- B27K3/00—Impregnating wood, e.g. impregnation pretreatment, for example puncturing; Wood impregnation aids not directly involved in the impregnation process
- B27K3/34—Organic impregnating agents
- B27K3/36—Aliphatic compounds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
- B27K5/00—Treating of wood not provided for in groups B27K1/00, B27K3/00
- B27K5/04—Combined bleaching or impregnating and drying of wood
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
- B27K2240/00—Purpose of the treatment
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
- B27K2240/00—Purpose of the treatment
- B27K2240/70—Hydrophobation treatment
-
- 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
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A20/00—Water conservation; Efficient water supply; Efficient water use
- Y02A20/20—Controlling water pollution; Waste water treatment
- Y02A20/204—Keeping clear the surface of open water from oil spills
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Forests & Forestry (AREA)
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Chemical And Physical Treatments For Wood And The Like (AREA)
Abstract
The invention relates to a super-hydrophobic material, and discloses a super-hydrophobic wood with demulsification capability, a preparation method and application thereof. The super-hydrophobic wood prepared by the invention has excellent super-hydrophobic stability and demulsification capability, high separation efficiency and strong electrothermal effect, can be used for demulsification and separation of high-efficiency and rapid common water-in-oil emulsion and high-viscosity crude oil emulsion, and can also be used for demulsification and separation of high-viscosity crude oil emulsion through electrothermal effect.
Description
Technical Field
The invention relates to a super-hydrophobic material, in particular to a super-hydrophobic wood, a preparation method and application thereof.
Background
The large discharge of industrial oily wastewater has posed a serious threat to the ecological environment, and the oil pollutants of water bodies are generally various and complex in form, and single-functional materials are difficult to meet the current treatment demands. Moreover, emulsion is used as an oil pollutant in a special state, has stable property and different particle sizes, and is difficult to separate by a common oil-water separation method.
At present, emulsion separation is mainly carried out by breaking emulsion and then separating the emulsion. Common demulsification methods such as an electric demulsification method, a chemical demulsification method and a biological demulsification method have the defects of high cost, low efficiency and secondary pollution. Among them, the most commonly used demulsifiers have gradually failed to meet the current requirements due to their toxicity and difficult recovery characteristics.
The Chen et al modified the nano carbon black with polyethyleneimine to prepare a demulsifier, and demulsified (Demulsification of oily wastewater using a nano carbon black modified with polyethyleneimine[J].Chemosphere,2022,295:133857.). the crude oil in water emulsion by charge neutralization of amino groups of polyethyleneimine, but the demulsifier is difficult to recover after being put into the emulsion, and is easy to cause secondary pollution to the environment. In addition, the demulsifier is difficult to disperse in high viscosity crude oil water-in-water, resulting in failure. Thus, there is still a great need to develop new emulsion breaking techniques.
The super-hydrophobic oleophylic material has different degrees of wettability on water and oil, can effectively realize oil-water separation, and is one of novel oil-water separation materials. The natural wood has a three-dimensional porous structure and a micro-nano coarse structure, is an advantageous material for super-hydrophobic materials for oil-water separation, and has the advantages of being green, efficient, low in cost and the like.
At present, super-hydrophobic timber has been studied in the field of oil-water separation, and has the advantages of simple preparation and excellent performance. Chinese patent No. CN114681953a discloses an asymmetric wetting wood film with switchable oil-water emulsion separation, one side of which has super-hydrophilicity/underwater super-oleophobicity, and the other side is super-hydrophobicity/super-lipophilicity; the wood film is capable of switchable separation of water-in-oil and oil-in-water emulsions.
Chinese patent No. 115155536A discloses a preparation method of a super-hydrophobic flame-retardant sponge capable of being used for selective adsorption. The sponge has excellent properties of hydrophobic and oleophilic in oil and oleophilic in water, and for oil-in-water emulsion, the super-hydrophobic sponge removes oil and water in the oil-in-water emulsion through simple adsorption.
However, the above materials have problems of low separation speed, single separation mode, general effect, difficulty in treating oil pollutants of complex components, and the like. Meanwhile, the holes of the material are easily polluted by the high-viscosity raw water-in-oil emulsion, so that the material is invalid. It is found that increasing the temperature of the raw water-in-oil emulsion can reduce the viscosity and enhance the fluidity, which is beneficial to the subsequent separation. Therefore, the multifunctional heatable super-hydrophobic material is developed and can be applied to demulsification and separation of incompatible oil pollutants and low-viscosity and high-viscosity raw water-in-oil emulsion, and has important significance for solving the oil pollution problem.
Disclosure of Invention
Aiming at the problems existing in the prior art in demulsification and separation of water-in-oil emulsion by the superhydrophobic material, the invention provides the superhydrophobic wood and the preparation method and application thereof.
In order to solve the technical problems, the invention is solved by the following technical scheme:
A preparation method of super-hydrophobic timber with demulsification capability comprises the steps of sequentially loading carboxylated carbon nanotubes, polyethylenimine and polydimethylsiloxane on timber, specifically, firstly loading the carboxylated carbon nanotubes on timber, then coating a carbon nanotube layer by using polyethylenimine through hydrogen bonding, and finally carrying out surface hydrophobic modification by using polydimethylsiloxane, thus obtaining the super-hydrophobic timber with demulsification capability.
Preferably, the method specifically comprises the following steps:
S1, pre-treating wood, namely placing the wood in a sodium hypochlorite solution, heating the wood for 4-12 hours at 70-100 ℃, and then placing the wood in a sodium hydroxide solution, heating the wood for 2-8 hours at 50-100 ℃ to form a spring-shaped structure; the method is mainly used for removing redundant wood tissues, wherein the wood is placed in sodium hypochlorite solution to remove part of hemicellulose and lignin, and placed in sodium hydroxide solution to further destroy the redundant wood tissues, so that the wood can form a compressible spring-like structure.
S2, placing wood in a carboxyl modified carbon nano tube solution, loading under the condition of heating and stirring, drying at 50-120 ℃, and repeating the process for 4-8 times to load the carboxylated carbon nano tube on the wood; the process enables carboxyl groups in the carboxyl modified carbon nano tube solution to form chemical bonds with hydroxyl groups on wood, and the carboxylated carbon nano tubes are loaded on the wood through the hydroxyl-carboxyl chemical bonds.
Step S3, freeze-drying the timber loaded with the carboxylated carbon nano tubes for 4-12 hours at the temperature of-45 ℃, then loading the timber in a polyethyleneimine solution with the weight percent of 0.5-5%, and drying the timber at the temperature of 60-100 ℃ to obtain the timber loaded with polyethyleneimine; in the process, polyethyleneimine is coated on the carboxylated carbon nano tube mainly through carboxyl-amino hydrogen bond action to form a firm layer-by-layer structure, so that the problems of easy shedding, unstable performance, secondary pollution and the like of the traditional material loading are solved, wherein the carboxylated carbon nano tube has the characteristics of large specific surface area, high inoculation rate, strong electric heating effect, good water dispersibility, easy loading and the like.
And S4, placing the wood loaded with the polyethyleneimine into 5-30wt% of polydimethylsiloxane solution, taking out, drying and curing for 2-6 hours at 60-100 ℃ to obtain the super-hydrophobic wood with demulsification capability. The process mainly utilizes polydimethylsiloxane to carry out surface hydrophobic modification, and the super-hydrophobic wood with excellent electrothermal and multifunctional synergistic demulsification capability is prepared.
Preferably, the wood in the step S1 is natural Basha wood, the density is 120-180kg/m 3, and the pore size is 10-80nm.
Preferably, the mass fraction of the sodium hypochlorite solution in the step S1 is 1-10wt% and the molar concentration of sodium hydroxide is 20-40mol/L.
Preferably, the carboxyl modified carbon nanotube solution in the step S2 is obtained by modifying carboxylated carbon nanotubes by concentrated sulfuric acid and concentrated nitric acid, specifically, the carboxylated carbon nanotubes are mixed with the concentrated sulfuric acid and the concentrated nitric acid at 70-100 ℃ for 1-5 hours, wherein the volumes of the concentrated sulfuric acid and the concentrated nitric acid are 6-12mL, and the volume ratio of the concentrated sulfuric acid to the concentrated nitric acid is 1:1-1:5, the concentration of the obtained carboxyl modified carbon nano tube solution is 2-10mg/mL, the inner diameter of the carboxylated carbon nano tube is 10-30nm, the outer diameter is 50-100nm, and the length is 10-30 mu m.
Preferably, the heating and stirring conditions in step S2 are such that the temperature is 50-100deg.C and the stirring speed is 270-540rpm.
Preferably, the polyethyleneimine solution in step S3 uses ethanol as a solvent, and includes polyethyleneimine having a molecular weight of 2000 to 10000.
Preferably, the polydimethylsiloxane solution in the step S4 is composed of polydimethylsiloxane, an organosilicon curing agent and a solvent, wherein the mass ratio of the polydimethylsiloxane to the organosilicon curing agent is 10:1, wherein the solvent is one or more of tetrahydrofuran, toluene, n-hexane, cyclohexane and methylene dichloride.
A super-hydrophobic wood with demulsification capability is prepared by a preparation method of the super-hydrophobic wood with demulsification capability. The prepared super-hydrophobic wood separates common oil-water mixture and low-viscosity emulsion by means of super-hydrophobic/oleophylic properties of the wood, n-pi and pi-pi actions of the carbon nano tube and the surfactant and charge neutralization action of amino groups of the polyethyleneimine on the emulsion. After voltage is applied, the surface of the wood can be quickly heated to reduce the viscosity of the high-viscosity raw water-in-oil emulsion, so as to realize demulsification and separation of the high-viscosity raw water-in-oil emulsion.
The super-hydrophobic wood with the demulsification capability is applied to separation of a common oil-water mixture, separation of a low-viscosity emulsion and demulsification separation of a high-viscosity crude oil emulsion, wherein the low-viscosity emulsion and the high-viscosity crude oil emulsion both contain stable emulsifying agents, the common oil-water mixture and the low-viscosity emulsion are a mixture or water-in-oil emulsion prepared from one of tetrahydrofuran, toluene, n-hexane, cyclohexane and methylene dichloride and water, and the high-viscosity emulsion is a crude oil-in-water emulsion prepared from crude oil with viscosity of 2000-10000 and water in an ultrasonic manner.
The invention has the remarkable technical effects due to the adoption of the technical scheme:
(1) The wood has the advantages of natural and renewable property, low cost, excellent mechanical property and the like, and the prepared super-hydrophobic wood has a compressible three-dimensional spring-shaped structure and stable super-hydrophobic property, and can be used for quickly separating and recovering a common oil-water mixture through an absorption-extrusion process.
(2) The super-hydrophobic wood prepared by the invention has excellent electric heating and multifunctional synergistic demulsification capability, and can quickly demulsifie and efficiently and quickly separate stable low-viscosity water-in-oil emulsion containing the surfactant by virtue of the super-hydrophobic/oleophylic performance of the wood, the n-pi and pi-pi actions of the carbon nano tube and the surfactant and the charge neutralization action of the amino groups of the polyethyleneimine on the emulsion, so that the viscosity of the raw water-in-oil emulsion is reduced and the fluidity of the raw water-in-oil emulsion is improved under the condition of applying voltage, thereby realizing the efficient and quick separation of the raw water-in-oil emulsion.
Drawings
FIG. 1 is a graph showing the IR spectrum of super-hydrophobic wood with demulsification ability obtained in example 1 of the present invention compared with that of natural wood and delignified wood.
Fig. 2 is a scanning electron microscope image of natural lumber.
FIG. 3 is a scanning electron microscope image of super-hydrophobic wood with demulsification capability obtained in example 1 of the present invention.
FIG. 4 is an optical microscope image before separation of the low-viscosity emulsion, respectively.
Fig. 5 is an optical microscope image after separation of the low-viscosity emulsion, respectively.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples.
Example 1
Firstly, wood (15X 15 mm) with the density of 120kg/m 3 is placed in a sodium hypochlorite solution with the concentration of 2wt percent and heated for 12 hours at 70 ℃, and then is placed in a sodium hydroxide solution with the concentration of 20mol/L and heated for 8 hours at 50 ℃ to remove lignin and hemicellulose; then, 0.2g of carbon nanotubes with an inner diameter of 10nm, an outer diameter of 50nm and a length of 10 μm were mixed with 8mL of concentrated sulfuric acid and concentrated nitric acid solution (the volume ratio of the concentrated sulfuric acid to the concentrated nitric acid is 1:2), and modified at 70℃for 3 hours; next, the wood is soaked in 2mg/mL carboxyl modified carbon nano tube solution, stirred and loaded at 270rpm and 50 ℃, and dried at 60 ℃, and the process is repeated for 6 times; subsequently, the wood is freeze-dried at the temperature of-45 ℃ and is soaked in a 5wt% polyethyleneimine ethanol solution with the molecular weight of 6000 for loading; finally, putting the wood into methylene dichloride solution containing 10wt% of polydimethylsiloxane for hydrophobic modification, taking out and curing for 3 hours at 80 ℃ to obtain the super-hydrophobic wood with excellent electrothermal and demulsification capabilities.
FIG. 1 is an infrared spectrum of natural wood, delignified wood, and superhydrophobic wood with electrothermal and demulsification capabilities in example 1. As can be seen from FIG. 1, the peaks of lignin of the natural lumber are 1590, 1650cm -1, and the peak of hemicellulose is 1730cm -1, respectively. After delignification, the characteristic peaks disappeared, indicating that the lignin and hemicellulose of the wood were successfully removed. After the carboxyl modified carbon nano tube, the polyethyleneimine and the polydimethylsiloxane are loaded, an amino characteristic peak of the polyethyleneimine is found at 1581cm -1, and a C-Si characteristic peak of the polydimethylsiloxane is found at 798cm -1, so that successful preparation of the material is proved.
As can be seen from fig. 2 and 3, the surface of the natural lumber has a dense structure, and most of the holes are covered by the tissues of the lumber. After delignification, the compact structure of the wood is destroyed, and a spring-like structure is formed, so that the material has compression performance. After carboxyl modified carbon nano tube, polyethyleneimine load and polydimethylsiloxane are hydrophobically modified, a uniform functional film is formed on the surface of wood. The special spring-shaped structure endows the wood with excellent compression-rebound capability, and the rapid separation of the oil-water mixture, the low-viscosity water-in-oil emulsion and the high-viscosity raw water-in-oil emulsion is realized by combining the demulsification performance and the electrothermal effect of the wood.
Fig. 4 and 5 are optical microscopic images before and after separation of the low-viscosity emulsion of this example 1, respectively, in which a large number of fine water droplets were present in the emulsion before separation. In the separated solution, however, no water droplets were observed, demonstrating successful separation of the emulsion.
To evaluate the superhydrophobicity of wood, contact angle measurement was performed on wood using a contact angle measuring instrument, and a contact angle of 156 ° was obtained, and the results are shown in table 1.
To evaluate the separation capacity of the wood from the oil-water mixture, toluene-water mixture (volume ratio 1:1) was prepared, and the wood was put into the mixture to be adsorbed, and the oil adsorption capacity was 8.7g/g.
In order to evaluate the electrothermal effect of wood, a power supply was used to apply a voltage to the wood, and the change in the surface temperature of the wood was measured by using a thermal infrared imager, and the wood was allowed to reach 154℃at 35V for 2 min.
To evaluate the separation performance of the low viscosity water-in-oil emulsion of wood, 10mL of a water-in-toluene emulsion (volume ratio of 99:1) was formulated, and 1.5mg/mL of surfactant span 80 (span 80) was added and sonicated for 1h. The timber is put into emulsion and stirred, and emulsion separation is realized through adsorption and charge neutralization, and the separation efficiency can reach 99.3%.
To evaluate the high viscosity raw water-in-oil emulsion separation of wood, the test was performed by a separation device consisting of a power source, super-hydrophobic wood, peristaltic pump and beaker. Wherein, super-hydrophobic timber is as heating and filter material, fixes in peristaltic pump's extraction opening department. 38mL of crude oil and 2mL of water were taken in a beaker and sonicated for 1h to simulate a simple water-in-crude oil emulsion. Electrodes are attached to two ends of the super-hydrophobic wood, the super-hydrophobic wood is placed on the surface of crude oil, a peristaltic pump is turned on, and a power supply is adjusted to 35V. Due to the excellent electrothermal effect of wood, the water-in-oil emulsion is heated rapidly, the viscosity is reduced, and the fluidity is enhanced. The peristaltic pump collects the crude oil into the beaker, and the water is blocked below the super-hydrophobic wood or adsorbed inside the wood, so that the separation of the crude oil water-in-oil emulsion is successfully realized. The result shows that the prepared super-hydrophobic wood can rapidly separate and recycle 7.3g of crude oil within 120s, and the separation efficiency can reach 93.1%.
Example 2
Firstly, wood (15X 15 mm) with a density of 140kg/m 3 is placed in a sodium hypochlorite solution with the concentration of 4wt% and heated for 10 hours at 80 ℃, and then is placed in a sodium hydroxide solution with the concentration of 30mol/L and heated for 5 hours at 60 ℃ to remove lignin and hemicellulose; then, 0.5g of carbon nanotubes with an inner diameter of 15nm, an outer diameter of 60nm and a length of 15 μm were mixed with 10mL of concentrated sulfuric acid and concentrated nitric acid solution (the volume ratio of concentrated sulfuric acid to concentrated nitric acid is 1:3), and modified at 80℃for 5 hours; next, the wood is soaked in 4mg/mL carboxyl modified carbon nano tube solution, stirred and loaded at 60 ℃ at 360rpm, and dried at 50 ℃, and the process is repeated for 8 times; subsequently, the wood was freeze-dried at-45 ℃ and immersed in a 4wt% polyethyleneimine ethanol solution having a molecular weight of 7000 for loading; finally, putting the wood into a dichloromethane solution containing 5wt% of polydimethylsiloxane for hydrophobic modification, taking out and curing for 2 hours at 100 ℃ to obtain the super-hydrophobic wood with excellent electrothermal and demulsification capabilities.
The contact angle measurement was performed on the superhydrophobic wood using a contact angle measuring instrument, and the contact angle was obtained to be 150 °. The test was conducted according to the oil-water mixture separation experiment of example 1, and it was found that the super-hydrophobic wood prepared in this example had an oil adsorption capacity of 10.2g/g. The test was performed according to the electrothermal effect experiment of example 1, and it was found that the super-hydrophobic wood prepared in this example could reach 160℃in 2 min. Experiments were performed as with the low viscosity water-in-oil emulsion of example 1, with separation efficiencies of up to 99.5%. The test is carried out according to the high-viscosity crude oil water-in-oil emulsion separation experiment of the example 1, the super-hydrophobic wood is rapidly separated and recovered to 9.2g of crude oil within 120s, and the separation efficiency can reach 93.4%. The results obtained are shown in Table 1.
Example 3
Firstly, wood (15X 15 mm) with a density of 150kg/m 3 is placed in a sodium hypochlorite solution with a concentration of 6wt% and heated at 90 ℃ for 8 hours, and then placed in a sodium hydroxide solution with a concentration of 40mol/L and heated at 80 ℃ for 3 hours to remove lignin and hemicellulose; then, 0.4g of carbon nanotubes with an inner diameter of 20nm, an outer diameter of 60nm and a length of 20 μm were mixed with 7mL of concentrated sulfuric acid and concentrated nitric acid solution (the volume ratio of concentrated sulfuric acid to concentrated nitric acid is 1:4), and modified at 90℃for 4 hours; next, the wood is soaked in 5mg/mL carboxyl modified carbon nano tube solution, stirred and loaded at 80 ℃ at 540rpm, and dried at 70 ℃, and the process is repeated for 6 times; subsequently, the wood is freeze-dried at-45 ℃ and soaked in a 3wt% polyethyleneimine ethanol solution with the molecular weight of 8000 for loading; finally, putting the wood into a dichloromethane solution containing 15wt% of polydimethylsiloxane for hydrophobic modification, taking out and curing for 4 hours at 90 ℃ to obtain the super-hydrophobic wood with excellent electrothermal and demulsification capabilities.
The contact angle measurement was performed on the superhydrophobic wood using a contact angle measuring instrument, and the contact angle was found to be 155 °. The test was conducted according to the oil-water mixture separation experiment of example 1, and it was found that the super-hydrophobic wood prepared in this example had an oil adsorption capacity of 9.6g/g. The test was performed according to the electrothermal effect experiment of example 1, and it was found that the superhydrophobic wood prepared in this example can reach 162 ℃ in 2 min. Experiments were performed as with the low viscosity water-in-oil emulsion of example 1, with separation efficiencies of up to 99.4%. The test is carried out according to the high-viscosity crude oil water-in-oil emulsion separation experiment of the example 1, the super-hydrophobic wood is rapidly separated and recovered to 9.3g of crude oil within 120s, and the separation efficiency can reach 93.5%. The results obtained are shown in Table 1.
Example 4
Firstly, wood (15X 15 mm) with a density of 160kg/m 3 is placed in a sodium hypochlorite solution with the concentration of 4wt% and heated for 10 hours at 90 ℃, and then is placed in a sodium hydroxide solution with the concentration of 30mol/L and heated for 4 hours at 100 ℃ to remove lignin and hemicellulose; then, 1g of carbon nanotubes with an inner diameter of 30nm, an outer diameter of 80nm and a length of 30 μm were mixed with 12mL of concentrated sulfuric acid and concentrated nitric acid solution (the volume ratio of concentrated sulfuric acid to concentrated nitric acid is 1:4), and modified at 100℃for 4 hours; next, the wood is soaked in 7mg/mL carboxyl modified carbon nano tube solution, stirred and loaded at 80 ℃ at 540rpm, and dried at 120 ℃, and the process is repeated for 3 times; subsequently, the wood is freeze-dried at-45 ℃ and soaked in a 2wt% polyethyleneimine ethanol solution with molecular weight of 8000 for loading; finally, putting the wood into a dichloromethane solution containing 20wt% of polydimethylsiloxane for hydrophobic modification, taking out and curing for 5 hours at 80 ℃ to obtain the super-hydrophobic wood with excellent electrothermal and demulsification capabilities.
The contact angle measurement was performed on the superhydrophobic wood using a contact angle measuring instrument, and the contact angle was found to be 153 °. The test was conducted as in the oil-water mixture separation experiment of example 1, and it was found that the super-hydrophobic wood prepared in this example had an oil adsorption capacity of 8.7g. The test was performed according to the electrothermal effect experiment of example 1, and it was found that the super-hydrophobic wood prepared in this example could reach 147 ℃ in 2 min. The separation efficiency can reach 99.3% by testing according to the low viscosity water-in-oil emulsion separation experiment of the example 1. The test is carried out according to the high-viscosity crude oil water-in-oil emulsion separation experiment of the example 1, 6.5g of crude oil is quickly separated and recovered from the super-hydrophobic wood within 120s, and the separation efficiency can reach 91.4%. The results obtained are shown in Table 1.
Example 5
Firstly, placing wood (15X 15 mm) with the density of 170kg/m 3 in a sodium hypochlorite solution with the weight percent of 8%, heating for 6 hours at the temperature of 100 ℃, and then placing the wood in a sodium hydroxide solution with the density of 25mol/L and heating for 5 hours at the temperature of 80 ℃ to remove lignin and hemicellulose; then, 0.5g of carbon nanotubes having an inner diameter of 20nm, an outer diameter of 50nm and a length of 20 μm was mixed with 10mL of concentrated sulfuric acid and concentrated nitric acid solution, and modified at 80℃for 3 hours; next, the wood is soaked in 4mg/mL carboxyl modified carbon nano tube solution, stirred and loaded at 80 ℃ at 480rpm, and dried at 120 ℃, and the process is repeated for 4 times; subsequently, the wood was freeze-dried at-45 ℃ and immersed in a 1.5wt% polyethyleneimine ethanol solution having a molecular weight of 9000 for loading; finally, putting the wood into a dichloromethane solution containing 30wt% of polydimethylsiloxane for hydrophobic modification, taking out and curing for 6 hours at 80 ℃ to obtain the super-hydrophobic wood with excellent electrothermal and demulsification capabilities.
The contact angle measurement was performed on the superhydrophobic wood using a contact angle measuring instrument, and the contact angle was obtained to be 150 °. The test was conducted as in the oil-water mixture separation experiment of example 1, and it was found that the super-hydrophobic wood prepared in this example had an oil adsorption capacity of 9.4g. The test was performed according to the electrothermal effect experiment of example 1, and it was found that the super-hydrophobic wood prepared in this example could reach 152℃in 2 min. The separation efficiency can reach 99.6% by testing according to the low viscosity water-in-oil emulsion separation experiment of the example 1. The test is carried out according to the high-viscosity crude oil water-in-oil emulsion separation experiment of the example 1, 7.0g of crude oil is quickly separated and recovered from the super-hydrophobic wood within 120 seconds, and the separation efficiency can reach 92.9%. The results obtained are shown in Table 1.
Example 6
Firstly, wood (15X 15 mm) with the density of 180kg/m 3 is placed in 10wt% sodium hypochlorite solution and heated for 2 hours at 90 ℃, and then placed in 40mol/L sodium hydroxide solution and heated for 8 hours at 100 ℃ to remove lignin and hemicellulose; then, 1.2g of carbon nanotubes having an inner diameter of 30nm, an outer diameter of 80nm and a length of 30 μm were mixed with 12mL of concentrated sulfuric acid and concentrated nitric acid solution, and modified at 100℃for 5 hours; next, the wood is soaked in 10mg/mL carboxyl modified carbon nano tube solution, stirred and loaded at 80 ℃ at 360rpm, and dried at 60 ℃, and the process is repeated for 4 times; subsequently, the wood is freeze-dried at the temperature of-45 ℃ and is soaked in a 1wt% polyethyleneimine ethanol solution with the molecular weight of 10000 for loading; finally, putting the wood into a dichloromethane solution containing 20wt% of polydimethylsiloxane for hydrophobic modification, taking out and curing for 4 hours at 100 ℃ to obtain the super-hydrophobic wood with excellent electrothermal and demulsification capabilities.
The contact angle measurement was performed on the superhydrophobic wood using a contact angle measuring instrument, and the contact angle was found to be 154 °. The test was conducted as in the oil-water mixture separation experiment of example 1, and it was found that the super-hydrophobic wood prepared in this example had an oil adsorption capacity of 13.2g. The test was performed according to the electrothermal effect experiment of example 1, and it was found that the super-hydrophobic wood prepared in this example could reach 153 deg.c in 2 min. The separation efficiency can reach 99.7% by testing according to the low viscosity water-in-oil emulsion separation experiment of the example 1. The test is carried out according to the high-viscosity crude oil water-in-oil emulsion separation experiment of the example 1, 7.2g of crude oil is quickly separated and recovered from the super-hydrophobic wood within 120 seconds, and the separation efficiency can reach 92.8%. The results obtained are shown in Table 1.
Comparative example 1
Wood (15 x 15 mm) having a density of 120kg/m 3 was placed in a 2wt% sodium hypochlorite solution and heated at 70 ℃ for 12 hours, and then placed in a 20mol/L sodium hydroxide solution and heated at 50 ℃ for 8 hours to remove lignin and hemicellulose; then, 0.2g of carbon nanotubes with an inner diameter of 10nm, an outer diameter of 50nm and a length of 10 μm were mixed with 8mL of concentrated sulfuric acid and concentrated nitric acid solution (the volume ratio of the concentrated sulfuric acid to the concentrated nitric acid is 1:2), and modified at 70℃for 3 hours; next, the wood is soaked in 2mg/mL carboxyl modified carbon nano tube solution, stirred and loaded at 270rpm and 50 ℃, and dried at 60 ℃, and the process is repeated for 1 time; subsequently, the wood is freeze-dried at the temperature of-45 ℃ and is soaked in a 5wt% polyethyleneimine ethanol solution with the molecular weight of 6000 for loading; finally, putting the wood into methylene dichloride solution containing 10wt% of polydimethylsiloxane for hydrophobic modification, taking out and curing for 3 hours at 80 ℃ to obtain the functionalized wood.
The contact angle measurement was performed on the superhydrophobic wood using a contact angle measuring instrument, and the contact angle was found to be 155 °. The test was conducted as in the oil-water mixture separation experiment of example 1, and it was found that the super-hydrophobic wood prepared in this example had an oil adsorption capacity of 7.4g. The test was carried out as in example 1, the electrothermal effect of wood was drastically reduced due to the reduction of the number of soaking times. The superhydrophobic wood prepared in this example was found to reach only 54 ℃ in 2 min. The test was carried out as in the low viscosity water-in-oil emulsion separation experiment of example 1, with a separation efficiency of 91.5%. The test was carried out according to the high-viscosity crude oil water-in-oil emulsion separation experiment of example 1, and 1.5g of crude oil was recovered by separation of the super-hydrophobic wood in 120 seconds, and the separation efficiency was 87.5%. The results obtained are shown in Table 1.
Comparative example 2
Firstly, wood (15X 15 mm) with the density of 120kg/m 3 is placed in a sodium hypochlorite solution with the concentration of 2wt percent and heated for 12 hours at 70 ℃, and then is placed in a sodium hydroxide solution with the concentration of 20mol/L and heated for 8 hours at 50 ℃ to remove lignin and hemicellulose; then, 0.2g of carbon nanotubes with an inner diameter of 10nm, an outer diameter of 50nm and a length of 10 μm were mixed with 8mL of concentrated sulfuric acid and concentrated nitric acid solution (the volume ratio of the concentrated sulfuric acid to the concentrated nitric acid is 1:2), and modified at 70℃for 3 hours; then, soaking the wood in a 5wt% polyethylenimine ethanol solution with the molecular weight of 6000 for loading; subsequently, the wood is soaked in 2mg/mL carboxyl modified carbon nano tube solution, stirred and loaded at 270rpm and 50 ℃, and dried at 60 ℃, and the process is repeated for 6 times; finally, putting the wood into methylene dichloride solution containing 10wt% of polydimethylsiloxane for hydrophobic modification, taking out and curing for 3 hours at 80 ℃ to obtain the super-hydrophobic wood with excellent electrothermal and demulsification capabilities.
The contact angle measurement was performed on the superhydrophobic wood using a contact angle measuring instrument, and the contact angle was found to be 154 °. The test was conducted as in the oil-water mixture separation experiment of example 1, and it was found that the super-hydrophobic wood prepared in this example had an oil adsorption capacity of 9.0g. The electrothermal effect test of example 1 was performed, and the electrothermal effect of wood was enhanced because the carbon nanotubes were wrapped in the outer layer of polyethyleneimine to form a good conductive path. The superhydrophobic wood prepared in this example was found to reach 167 ℃ at 2 min. The test was performed as in the low viscosity water-in-oil emulsion separation test of example 1, since the carbon nanotubes were extremely easily detached after contacting the emulsion, the separation test was not performed. The test was performed as in example 1, the high viscosity crude water-in-oil emulsion separation experiment, since the carbon nanotubes were very easily detached after contacting the emulsion, losing the electrothermal effect, and the separation experiment could not be performed. The results obtained are shown in Table 1.
Comparative example 3
Wood (15 x 15 mm) having a density of 120kg/m 3 was placed in a 2wt% sodium hypochlorite solution and heated at 70 ℃ for 12 hours, and then placed in a 20mol/L sodium hydroxide solution and heated at 50 ℃ for 8 hours to remove lignin and hemicellulose; then, 0.2g of carbon nanotubes with an inner diameter of 10nm, an outer diameter of 50nm and a length of 10 μm were prepared into a carbon nanotube solution of 2 mg/mL; next, the wood was immersed in the carbon nanotube solution, stirred at 270rpm under 50 ℃ for loading, and dried at 60 ℃, and this procedure was repeated 1 time; subsequently, the wood is freeze-dried at the temperature of-45 ℃ and is soaked in a 5wt% polyethyleneimine ethanol solution with the molecular weight of 6000 for loading; finally, putting the wood into methylene dichloride solution containing 10wt% of polydimethylsiloxane for hydrophobic modification, taking out and curing for 3 hours at 80 ℃ to obtain the functionalized wood.
The contact angle measurement was performed on the superhydrophobic wood using a contact angle measuring instrument, and the contact angle was found to be 152 °. The test was conducted as in the oil-water mixture separation experiment of example 1, and it was found that the super-hydrophobic wood prepared in this example had an oil adsorption capacity of 5.4g. The electrothermal effect test of example 1 was performed, and since the carbon nanotubes were not modified, the dispersibility was extremely poor and it was difficult to load the carbon nanotubes on the wood by dipping. The super-hydrophobic wood prepared in the embodiment can only reach 34 ℃ in 2 min. The low viscosity water-in-oil emulsion separation experiment of example 1 was tested and the emulsion was difficult to separate due to the lack of adsorption of the surfactant by the carbon nanotubes and immobilization of the polyethyleneimine. The high viscosity raw water-in-oil emulsion separation test of example 1 was performed, and the material could not reduce the viscosity of the raw water-in-oil emulsion by heating due to the extremely bad electrothermal effect, resulting in failure of the separation test. The results obtained are shown in Table 1.
Table 1 shows the water contact angle and oil adsorption capacity thereof, the surface temperature and water-in-oil emulsion separation efficiency of 120s at a voltage of 35V, and the recovery amount and efficiency of crude oil water-in-oil emulsion separation crude oil of the superhydrophobic lumber according to the embodiment of the invention.
From the contact angle data, the surface temperature and the crude oil recovery data of the examples in table 1, it can be seen that the superhydrophobic wood obtained in examples 1-6 has good superhydrophobic performance, good adsorption capacity and excellent electrothermal effect, and can rapidly demulsifie and separate the low-viscosity water-in-oil emulsion and the high-viscosity crude oil emulsion.
Compared with the example 1, the comparative example 1 still has better superhydrophobic performance, but the electrothermal effect is greatly reduced, and meanwhile, the separation efficiency of the water-in-oil emulsion and the separation recovery amount of the water-in-oil emulsion are also reduced. This means that when the number of soaking times is changed, the amount of carboxylated carbon nanotubes loaded by the wood is changed, and the electrothermal effect of the wood and the subsequent separation of the raw water-in-oil emulsion are greatly affected.
Compared with the example 1, the carbon nano tube of the comparative example 2 is wrapped outside the polyethylenimine due to the change of the loading sequence of the carbon nano tube and the polyethylenimine, so that a better conductive path is formed, the electrothermal effect is obviously enhanced, but the carbon nano tube is fixed only through the action of hydrogen bonds and is very easy to fall off, so that the separation experiment is invalid. This suggests that the order of loading of carbon nanotubes and polyethyleneimine is important for the performance stability of wood.
In comparison with example 1, since the carbon nanotubes were not modified, water dispersibility was poor and it was difficult to load on the wood, the adsorption capacity of the superhydrophobic wood of ratio 3 was lowered, and the electrothermal effect and the separation capacity were deteriorated. This shows that carboxylated carbon nanotubes have important roles in the adsorption performance, demulsification capability and electrothermal effect of wood.
The super-hydrophobic wood prepared by the invention has excellent super-hydrophobic stability and demulsification capability, high separation efficiency and strong electrothermal effect, can be used for demulsification and separation of high-efficiency and rapid common water-in-oil emulsion and high-viscosity crude oil emulsion, and can also be used for demulsification and separation of high-viscosity crude oil emulsion through electrothermal effect.
The above examples are merely a few specific preparation methods and detailed data of the present invention, and it is obvious to those skilled in the art that modifications or substitutions can be made thereto, which fall within the scope of the present invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.
Note that: performance testing
(1) Contact angle test: the contact angle measurement was performed on wood using an SDC-200S contact angle measuring instrument, a company of Cheng' S precision instruments, dongguan, and the measured water drop was 5. Mu.L, and each sample was measured 5 times, and an average value was obtained.
(2) And (3) testing an electrothermal effect: the temperature measurement was performed on the wood using a thermal infrared imager of Fotric C, feijiaceae, to evaluate the electrothermal effect of the wood with temperature.
(3) The purity of the oil before and after separation was measured by Vario TOC total organic carbon analyzer and the separation efficiency was calculated.
It is to be understood that, based on one or several embodiments provided in the present application, those skilled in the art may combine, split, reorganize, etc. the embodiments of the present application to obtain other embodiments, which do not exceed the protection scope of the present application.
In summary, the foregoing description is only of the preferred embodiments of the present invention, and all equivalent changes and modifications made in accordance with the claims should be construed to fall within the scope of the invention.
Claims (8)
1. A preparation method of super-hydrophobic wood with demulsification capability is characterized by comprising the following steps: sequentially loading carboxylated carbon nanotubes, polyethyleneimine and polydimethylsiloxane on wood, specifically, firstly loading the carboxylated carbon nanotubes on the wood, then coating a carbon nanotube layer by using polyethyleneimine through hydrogen bonding, and finally carrying out surface hydrophobic modification by using the polydimethylsiloxane to obtain the super-hydrophobic wood with demulsification capability; the method specifically comprises the following steps:
S1, pre-treating wood, namely placing the wood in a sodium hypochlorite solution and heating the wood for 4-12 hours at 70-100 ℃, and then placing the wood in a sodium hydroxide solution and heating the wood for 2-8 hours at 50-100 ℃ to form a spring-shaped structure;
S2, placing wood in a carboxyl modified carbon nano tube solution, loading under the condition of heating and stirring, drying at 50-120 ℃, and repeating the process for 4-8 times to load the carboxylated carbon nano tube on the wood;
Step S3, freeze-drying the timber loaded with the carboxylated carbon nano tubes for 4-12 hours at the temperature of-45 ℃, then loading the timber in a polyethyleneimine solution with the weight percent of 0.5-5%, and drying the timber at the temperature of 60-100 ℃ to obtain the timber loaded with polyethyleneimine;
S4, placing the wood loaded with the polyethyleneimine into 5-30wt% of polydimethylsiloxane solution, taking out, drying and curing for 2-6 hours at 60-100 ℃ to obtain the super-hydrophobic wood with demulsification capability;
The carboxyl modified carbon nanotube solution in the step S2 is obtained by modifying carbon nanotubes by concentrated sulfuric acid and concentrated nitric acid, specifically, the carboxyl modified carbon nanotube solution is obtained by mixing carbon nanotubes with the inner diameter of 10-30nm, the outer diameter of 50-100nm and the length of 10-30 mu m with concentrated sulfuric acid and concentrated nitric acid for 1-5 hours at the temperature of 70-100 ℃, wherein the volumes of the concentrated sulfuric acid and the concentrated nitric acid are 6-12mL, and the volume ratio of the concentrated sulfuric acid to the concentrated nitric acid is 1:1-1:5, the concentration of the obtained carboxyl modified carbon nano tube solution is 2-10mg/mL.
2. The method for preparing the super-hydrophobic wood with demulsification capability according to claim 1, which is characterized by comprising the following steps: in the step S1, the wood is natural Basha wood, the density is 120-180kg/m 3, and the pore size is 10-80nm.
3. The method for preparing the super-hydrophobic wood with demulsification capability according to claim 1, which is characterized by comprising the following steps: in the step S1, the mass fraction of the sodium hypochlorite solution is 1-10wt%, and the molar concentration of sodium hydroxide is 20-40mol/L.
4. The method for preparing the super-hydrophobic wood with demulsification capability according to claim 1, which is characterized by comprising the following steps: in the step S2, the heating and stirring conditions are that the temperature is 50-100 ℃ and the stirring speed is 270-540rpm.
5. The method for preparing the super-hydrophobic wood with demulsification capability according to claim 1, which is characterized by comprising the following steps: in the step S3, the polyethyleneimine solution takes ethanol as a solvent and comprises polyethyleneimine with the molecular weight of 2000-10000.
6. The method for preparing the super-hydrophobic wood with demulsification capability according to claim 1, which is characterized by comprising the following steps: the polydimethylsiloxane solution in the step S4 consists of polydimethylsiloxane, a curing agent and a solvent, wherein the mass ratio of the polydimethylsiloxane to the curing agent is 10:1, wherein the solvent is one or more of tetrahydrofuran, toluene, n-hexane, cyclohexane and methylene dichloride.
7. A superhydrophobic wood having a demulsification ability, which is prepared by the method for preparing a superhydrophobic wood having a demulsification ability according to any one of claims 1 to 6.
8. The application of the super-hydrophobic wood with demulsification capability is characterized in that the super-hydrophobic wood with demulsification capability as claimed in claim 7 is applied to separation of common oil-water mixtures, separation of low-viscosity emulsions and demulsification separation of high-viscosity crude oil emulsions.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310802965.1A CN117001796B (en) | 2023-07-03 | 2023-07-03 | Super-hydrophobic wood with demulsification capability and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310802965.1A CN117001796B (en) | 2023-07-03 | 2023-07-03 | Super-hydrophobic wood with demulsification capability and preparation method and application thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN117001796A CN117001796A (en) | 2023-11-07 |
| CN117001796B true CN117001796B (en) | 2024-05-28 |
Family
ID=88570157
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310802965.1A Active CN117001796B (en) | 2023-07-03 | 2023-07-03 | Super-hydrophobic wood with demulsification capability and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117001796B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111978856A (en) * | 2020-07-20 | 2020-11-24 | 华南理工大学 | Super-hydrophilic/underwater super-oleophobic copper mesh, preparation method thereof and application of copper mesh in separation of emulsified oil-in-water |
| CN113499760A (en) * | 2021-07-15 | 2021-10-15 | 东莞理工学院 | High-flux super-hydrophobic wood, preparation method and application thereof |
| CN115068979A (en) * | 2022-06-09 | 2022-09-20 | 东莞理工学院 | Super-hydrophobic wood with excellent electrothermal and photothermal effects and preparation method and application thereof |
| CN115785990A (en) * | 2022-12-22 | 2023-03-14 | 南阳腾远石油工程技术服务有限公司 | Crude oil demulsifier and preparation method thereof |
-
2023
- 2023-07-03 CN CN202310802965.1A patent/CN117001796B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111978856A (en) * | 2020-07-20 | 2020-11-24 | 华南理工大学 | Super-hydrophilic/underwater super-oleophobic copper mesh, preparation method thereof and application of copper mesh in separation of emulsified oil-in-water |
| CN113499760A (en) * | 2021-07-15 | 2021-10-15 | 东莞理工学院 | High-flux super-hydrophobic wood, preparation method and application thereof |
| CN115068979A (en) * | 2022-06-09 | 2022-09-20 | 东莞理工学院 | Super-hydrophobic wood with excellent electrothermal and photothermal effects and preparation method and application thereof |
| CN115785990A (en) * | 2022-12-22 | 2023-03-14 | 南阳腾远石油工程技术服务有限公司 | Crude oil demulsifier and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN117001796A (en) | 2023-11-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Zhang et al. | Biomimetic preparation of a polycaprolactone membrane with a hierarchical structure as a highly efficient oil–water separator | |
| Rong et al. | A facile strategy toward 3D hydrophobic composite resin network decorated with biological ellipsoidal structure rapeseed flower carbon for enhanced oils and organic solvents selective absorption | |
| Bhuyan et al. | Cellulose nanofiber-poly (ethylene terephthalate) nanocomposite membrane from waste materials for treatment of petroleum industry wastewater | |
| Wang et al. | Lignin/sodium alginate hydrogel for efficient removal of methylene blue | |
| Song et al. | Grass-modified graphene aerogel for effective oil-water separation | |
| Piperopoulos et al. | Synthesis of reusable silicone foam containing carbon nanotubes for oil spill remediation | |
| Liu et al. | A superhydrophobic sponge with hierarchical structure as an efficient and recyclable oil absorbent | |
| CN113499760A (en) | High-flux super-hydrophobic wood, preparation method and application thereof | |
| Chen et al. | Facile fabrication of corn stover-based aerogel for oil/water separation | |
| Xiao et al. | Bioinspired Janus membrane of polyacrylonitrile/poly (vinylidene fluoride)@ poly (vinylidene fluoride)-methyltriethoxysilane for oil-water separation | |
| CN113058439A (en) | Super-hydrophobic two-dimensional anti-pollution demulsification oil-water separation membrane material and preparation method and application thereof | |
| CN115055170A (en) | Wood-based modified nano-cellulose water purification material with high adsorption performance and preparation method and application thereof | |
| CN117001796B (en) | Super-hydrophobic wood with demulsification capability and preparation method and application thereof | |
| Sun et al. | Rapid and stable plasma transformation of polyester fabrics for highly efficient oil–water separation | |
| Li et al. | Renewable superhydrophobic PVB/SiO2 composite membranes with self-repairing for high-efficiency emulsion separation | |
| Zhu et al. | Efficient adsorption of oil in water by hydrophobic nonwoven fabrics coated with cross‐linked polydivinylbenzene fibers | |
| Chen et al. | Superhydrophobic PDMS@ PEI-cCNTs wood with Joule heat and demulsification capability for oil-water emulsion separation | |
| CN110280048A (en) | A kind of lower super hydrophobic material of underwater superoleophobic/oil and its non-solvent preparation for oil hydrosol separation | |
| Ghaedi et al. | Facile fabrication of robust superhydrophobic polyurethane sponge modified with polydopamine-silica nanoparticle for effective oil/water separation | |
| CN109517169B (en) | Amphiphilic hyperbranched polymer and preparation and application thereof | |
| Ma et al. | A novel cost-effective kapok fibers and regenerated cellulose-based carbon aerogel for continuous oil/water separation | |
| Guo et al. | Silica-modified electrospun membrane with underwater superoleophobicity for effective gravity-driven oil/water separation | |
| Wang et al. | Polyethylenimine-modified glass fiber by a sulfur-based coupling reaction for selective demulsification of oil/water emulsions | |
| CN109503833B (en) | Amphiphilic hyperbranched polymer and preparation and application thereof | |
| CN114031803B (en) | Method for preparing polyamide-amine gel composite membrane based on click chemistry and application |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |