CN114504844B - Coalescence material, preparation method thereof and oil removal method - Google Patents
Coalescence material, preparation method thereof and oil removal method Download PDFInfo
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- CN114504844B CN114504844B CN202011167115.1A CN202011167115A CN114504844B CN 114504844 B CN114504844 B CN 114504844B CN 202011167115 A CN202011167115 A CN 202011167115A CN 114504844 B CN114504844 B CN 114504844B
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- 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
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- 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
- B01D17/04—Breaking emulsions
- B01D17/045—Breaking emulsions with coalescers
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/40—Devices for separating or removing fatty or oily substances or similar floating material
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- 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
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- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention provides a coalescing material, a preparation method thereof and an oil removal method. The coalescing material of the present invention comprises: a base material; siO deposited on the surface of the substrate material 2 Particles; coating the SiO 2 Particles and polysiloxane on the surface of the substrate material. The coalescing material has low surface energy, physiological inertia, good chemical stability and high and low temperature resistance; furthermore, polysiloxane vs. inorganic SiO 2 The particles and the substrate material have excellent cohesiveness, so that the formed composite coating and the substrate material have stronger bonding capability and higher shearing resistance, and are not easy to peel off under the impact of water flow. The coalescing material provided by the invention is durable in use, has excellent oleophylic and hydrophobic properties on the surface, and can forcefully promote coalescence and buoyancy of dispersed phase oil drops when being used for removing oil from wastewater, so that the oil removal efficiency is improved.
Description
Technical Field
The invention belongs to the field of oil-water separation, and particularly relates to a coalescing material suitable for oil removal of oily wastewater and a preparation method thereof.
Background
The crude oil is produced, transported, stored and refined to produce a great amount of oily waste water, which has complex components and great treatment difficulty and seriously threatens the water environment and human health. Petroleum substances in oily wastewater can be generally classified into floating oil, dispersed oil, emulsified oil and dissolved oil according to physical state. Because water has low solubility to common petroleum substances, the wastewater oil removal mainly aims at floating oil, dispersed oil and emulsified oil, wherein the technical difficulty of separating and removing the emulsified oil is highest.
At present, the oil removal method for wastewater can be categorized into four main categories: physical, chemical, physicochemical, and biochemical methods. The physical method is a separation method implemented by utilizing the differences of physical properties such as oil-water two-phase density, wettability and spreadability on the surface of a solid material, existence of morphology and the like, and mainly comprises methods such as gravity sedimentation, cyclone, coalescence, filtration separation, membrane separation and the like. The chemical method mainly comprises coagulation/flocculation sedimentation, namely adding a proper amount of chemical agent (coagulant or flocculant) into the wastewater to destroy the stability of an oil-water interface, so that small-particle-size oil drops and the coagulant/flocculant are promoted to form floccules which are easy to settle. The physical and chemical method combines physical separation and chemical separation, thereby achieving the purpose of oil-water separation. For example, air flotation processes typically require the addition of flocculants or demulsifiers to the wastewater in order to increase the efficiency of oil removal. The biological method is to degrade and consume petroleum hydrocarbon in the sewage by utilizing microorganisms, and mainly comprises an activated sludge method, a biological filter method, an aeration biological filter method and the like. Each oil removing method has advantages and disadvantages, and one method cannot reach the expected oil removing target. Several processes are often combined in series according to the actual demands of production, for example, "gravity settling (removal of oil slick) +air flotation/coagulation/coalescence etc. (removal of dispersed oil, emulsified oil) +bio/filtration (advanced treatment)". Among the above-mentioned several types of oil removal methods, the physical method does not affect the quality of the recovered oil; moreover, the coalescing method has the advantages of small equipment, simple operation, low cost and the like, is regarded as an excellent and wide-prospect oil removal method, and is widely researched and applied.
By "coalescing" (or "coarse granulation") is meant that the oily wastewater passes through a device filled with a material of particular wettability which promotes coalescence of the dispersed phase oil droplets and thus increases their particle size; these particular materials are known as "coalescing materials" (or "coarse grained materials"). According to stokes' law, the terminal rate of rise of oil droplets in the aqueous phase is proportional to the square of their particle size, so that coalescence of the oil droplets can enhance their lift separation in the aqueous phase. The coalescence degreasing technology comprises coalescence of oil drops and a corresponding buoyancy separation process, and the technology utilizes the characteristic that the affinities of oil water and water relative to the surface of a coalescence material are greatly different (namely, the oleophilic and hydrophobic characteristics of the surface of the material).
Currently, most views consider that the coalescing oil removal mechanism is broadly divided into two types: collisional coalescence and wetted coalescence. The collision coalescence, namely that small-particle-size oil drops are directly coalesced into large-particle-size oil drops, and the coalescence material provides a flow passage space for coalescence of the oil drops, so that the collision probability among the oil drops is improved. Wetting aggregation is considered that oil drops firstly wet and spread on the coalescing material due to the fact that the surface of the coalescing material has a large affinity to an oil phase, and then the oil drops collide with the oil drops which are firstly adhered to form an oil film; when the thickness of the oil film is increased to a certain extent, the oil film falls off from the surface of the material under the action of buoyancy and water flow drag force to form large-particle-size oil drops, so that the purpose of enhancing the buoyancy and separation of the oil drops is achieved.
From the above coalescing mechanism, it can be seen that coalescing materials are the core of coalescing oil removal technology; the physical and chemical properties and structural characteristics of the surface of the coalescing material determine the wettability and adhesiveness of the coalescing material, and further determine the oil-water separation efficiency. The coalescing materials commonly used today include polypropylene, polyvinyl chloride, stainless steel fibers, fiberglass, and the like, which are commonly found with the following problems: the emulsion oil stable to natural/non-natural surface active substances has poor effect and the coalescing effect needs to be further improved.
The bionic super-wetting material is a material similar to a living body in nature and having special infiltration interface properties. In the last twenty years, researchers have revealed a series of construction mechanisms of super-wetting interface materials by simulating nature, designed and prepared various bionic super-wetting materials, and developed and applied the materials with special surface wetting properties to various fields including oil-water separation. Research proves that from the bionic point of view, a micrometer/nanometer multi-scale coarse structure is constructed on the surface, and the surface is modified by a low-surface energy substance, so that the coalescence material with high oil removal efficiency can be prepared. Based on the principle, researchers construct a multi-scale rough surface through a template method, an etching method, a chemical deposition method, a layer-by-layer self-assembly method, a sol-gel method and the like, and then coat or modify low-surface-energy substances, so that various coalescent degreasing materials are designed. However, these coalescing oil removal materials are relatively complex to prepare and the low surface energy components used to modify the surface are mostly fluorine-containing compounds that present a potential environmental risk. Therefore, the coalescing oil removal material which is simple in development and preparation process and environment-friendly has realistic urgency and wide application prospect.
Disclosure of Invention
The invention provides a coalescing material, a preparation method thereof and an oil removal method.
The coalescing material of the present invention comprises: a base material; siO deposited on the surface of the substrate material 2 Particles; coating the SiO 2 Particles and polysiloxane on the surface of the substrate material.
According to the present invention, the base material is preferably an inorganic base material. The inorganic base material is preferably a metal material, and one or more of a metal wire mesh, a metal sheet and a metal disc can be selected. The pore size of the wire mesh is preferably 3 to 90 μm. The metal in the metal material may be one or more of steel, iron, copper and titanium. The metallic material is preferably one or more of stainless steel wire mesh, iron wire mesh, copper wire mesh and titanium wire mesh, more preferably stainless steel wire mesh.
According to the invention, the polysiloxane has a structure shown in formula (I):
wherein n is an integer between 1 and 1400, preferably 100 to 1200, more preferably 140 to 1000; each R group is independently selected from C 1 ～C 8 Alkyl, C of (2) 1 ～C 2 Alkoxy, C 1 ～C 3 Haloalkyl, C 2 ～C 5 Alkenyl, phenyl, preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, methoxy, ethoxy, trifluoropropyl, vinyl, phenyl, more preferably methyl;
wherein the A group is selected fromH、Wherein each R group is independently selected from C 1 ～C 3 Alkyl, C of (2) 1 ～C 3 Preferably methyl, methoxy, ethyl, ethoxy, propyl, propoxy, more preferably methyl, each R' group being independently selected from H, C 1 ～C 3 Preferably H, methyl, more preferably H, R' is selected from C 1 ～C 6 Alkylene of (C) is preferred 1 ～C 4 More preferably methylene, ethylene, propylene, butylene;
wherein the A' group is selected from OH,Wherein each R' group is independently selected from H, C 1 ～C 3 Preferably H, methyl, more preferably H; each R' group is independently selected from C 1 ～C 6 Alkylene of (C) is preferred 1 ～C 4 More preferably methylene, ethylene, propylene, butylene.
According to the invention, the polysiloxane is preferably a polysiloxane of the formula (II) and/or formula (III):
wherein n is each independently an integer between 1 and 1400, preferably 100 to 1200, more preferably 140 to 1000; each R group is independently selected from C 1 ～C 8 Alkyl, C of (2) 1 ～C 2 Alkoxy, C 1 ～C 3 Haloalkyl, C 2 ～C 5 Alkenyl, phenyl, preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, methoxy, ethoxy, trifluoropropyl, vinyl, phenyl, more preferably methyl; each R' group is independently selected from H, C 1 ～C 3 Is a group comprising an alkyl group,preferably H, methyl, more preferably H, each R' group being selected from C 1 ～C 6 Alkylene of (C) is preferred 1 ～C 4 More preferably methylene, ethylene, propylene, butylene.
The preparation method of the coalescing material comprises the following steps:
(1) Coating a first polysiloxane solution on a substrate material, drying and solidifying the substrate material at 80-130 ℃, roasting the substrate material at 400-600 ℃ for 2-4 hours, and cooling the substrate material to 0-35 ℃ to obtain an intermediate material;
(2) And coating a second polysiloxane solution on the intermediate material, and drying and curing at 80-130 ℃.
According to the invention, the solute of the polysiloxane solution is polysiloxane and optional curing agent, and the solvent is one or more of tetrahydrofuran, n-hexane, n-heptane, a mixed solution of tetrahydrofuran and water, preferably tetrahydrofuran or a mixed solution of tetrahydrofuran and deionized water. The optional curing agent is preferably a silicone curing agent, for example, one or more of aniline methyltriethoxysilane, ethyl orthosilicate, and aminopropyl triethoxysilane may be used. The polysiloxane is preferably a polysiloxane as described in any one of the preceding aspects. In the polysiloxane solution, the mass concentration of the solute is preferably 0.2% to 10%, more preferably 0.3% to 7%.
According to the invention, the mass concentration of solute in the first polysiloxane solution is preferably 1.8% to 10%, more preferably 2% to 7%; the concentration of solute in the second polysiloxane solution is preferably 0.2% to 2%, more preferably 0.5% to 1.7%.
According to the invention, the solute in the first polysiloxane solution is preferably a mixture of polysiloxane and curing agent, and the solvent is preferably a mixture of tetrahydrofuran and deionized water, wherein the mass ratio of polysiloxane, curing agent, tetrahydrofuran and deionized water is preferably 1: 0.095-0.105: 5 to 14:10 to 35.
According to the invention, the solute in the second polysiloxane solution is preferably a mixture of polysiloxane and curing agent, and the solvent is preferably a mixture of tetrahydrofuran and deionized water, wherein the mass ratio of polysiloxane, curing agent, tetrahydrofuran and deionized water is preferably 1: 0.095-0.105: 18 to 59: 46-140.
According to the present invention, the method of applying the polysiloxane solution to the base material or the intermediate material includes one or more of dip-pull, spray coating, and spin coating.
According to the present invention, the substrate material is preferably subjected to a cleaning pretreatment prior to the application of the first polysiloxane solution to the surface of the substrate material, more preferably to an ultrasonic cleaning pretreatment of the substrate material in a cleaning liquid, which may be selected from common cleaning liquids, preferably ketones, alcohols and/or water, more preferably acetone, absolute ethanol or deionized water. The cleaning pretreatment can be carried out once or more times, and when the cleaning pretreatment is carried out for a plurality of times, the cleaning liquid can be the same or different, and preferably, the cleaning pretreatment is carried out by sequentially using acetone and absolute ethyl alcohol, and then the cleaning pretreatment is carried out by using deionized water. The ultrasonic cleaning pretreatment is preferably carried out for 5 to 30 minutes, more preferably 10 to 25 minutes, and optionally comprises drying or naturally airing the substrate material subjected to the cleaning pretreatment.
According to the present invention, the temperature at which the drying and curing are performed in the step (1) is preferably 90 to 125 ℃, more preferably 95 to 110 ℃, and the time for performing the drying and curing is preferably 0.3 to 6 hours, more preferably 3 to 5 hours.
According to the present invention, the temperature at which the drying and curing are performed in the step (2) is preferably 90 to 125 ℃, more preferably 95 to 110 ℃, and the time for performing the drying and curing is preferably 0.3 to 6 hours, more preferably 3 to 5 hours.
The invention utilizes polysiloxane to modify the substrate material in two steps to prepare the coalescing material, firstly, the substrate material coated with polysiloxane solution is baked at high temperature, and the polysiloxane is degraded to obtain SiO 2 The particles can be deposited on the substrate material, so that a micron/nano structure is constructed on the surface of the substrate material, and the roughness of the surface of the substrate material is further increased; then, polysiloxane is coated on the deposited SiO 2 On the base material of the particles, therebyThe surface of the base material is coated with SiO by polysiloxane 2 An organic-inorganic composite coating of particles; finally, the coalescent material with excellent and durable oleophilic and hydrophobic properties is obtained.
The coalescing material has low surface energy, physiological inertia, good chemical stability and high and low temperature resistance; furthermore, polysiloxane vs. inorganic SiO 2 The particles and the substrate material have excellent cohesiveness, so that the formed composite coating and the substrate material have stronger bonding capability and higher shearing resistance, and are not easy to peel off under the impact of water flow. The metal wire mesh used as the base material is low in price and can be reused; the preparation method of the coalescing material is simple, efficient, environment-friendly, suitable for large-scale production and does not involve fluorination treatment.
The coalescing material provided by the invention is durable, the surface of the coalescing material has excellent oleophylic and hydrophobic properties, the static contact angle of a water drop on the surface of the coalescing material is larger than 125 degrees, the static contact angle of an oil drop on the surface of the coalescing material is close to 0 degree, and the oil drop can be quickly wetted and spread on the surface of the coalescing material; when the oil remover is used for removing oil from wastewater, the coalescence of dispersed phase oil drops can be forcefully promoted, so that the rate of oil drops floating from a water body is enhanced, and the oil removal efficiency is improved.
The coalescing material of the present invention can be used as a coalescing oil removal material.
Drawings
FIG. 1 is an electron microscope scan of a coalescing material produced in example 2 of the present invention, at 10000 times magnification.
FIG. 2 is an electron microscope scan of the coalescing material produced in example 2 of the present invention, at 5000 x magnification.
FIG. 3 is an electron microscope scan of the coalescing material produced in example 2 of the present invention, at 1000 x magnification.
FIG. 4 is an electron microscope scan of the coalescing material produced in example 2 of the present invention, at 100 x magnification.
Fig. 5 is a static contact angle of a water droplet on the surface of the coalescing material produced in example 2 of the present invention.
Fig. 6 is a static contact angle of oil droplets on the surface of the coalescing material prepared in example 2 of the present invention.
Detailed Description
The following detailed description of embodiments of the invention is provided, but it should be noted that the scope of the invention is not limited by these embodiments, but is defined by the appended claims.
In the context of this specification, any matters or matters not mentioned are directly applicable to those known in the art without modification except as explicitly stated. Moreover, any embodiment described herein can be freely combined with one or more other embodiments described herein, and the technical solutions or ideas thus formed are all deemed to be part of the original disclosure or original description of the present invention, and should not be deemed to be a new matter which has not been disclosed or contemplated herein, unless such combination is clearly unreasonable by those skilled in the art.
Unless explicitly indicated, all percentages, parts, ratios, etc. referred to in this specification are on a mass basis unless otherwise indicated as being inconsistent with conventional knowledge by those skilled in the art.
The following describes specific embodiments of the present invention in detail. It should be understood that the detailed description and specific examples, while indicating and illustrating the invention, are not intended to limit the invention.
The method of making the coalescing material of example 1 includes the steps of: (1) Sequentially placing the inorganic substrate material into absolute ethyl alcohol and deionized water, respectively ultrasonically washing for 25min and 10min, and drying; coating a first polysiloxane solution on an inorganic substrate material, drying and solidifying the inorganic substrate material in a vacuum oven at 98 ℃ for 5 hours, then placing the inorganic substrate material in a muffle furnace, roasting the inorganic substrate material at 490 ℃ for 2.5 hours, and cooling the inorganic substrate material to room temperature to obtain an intermediate material; (2) And (3) coating a second polysiloxane solution on the intermediate material, and drying and curing the intermediate material in a vacuum oven at 98 ℃ for 5 hours to obtain the coalescing material.
The method of making the coalescing material of example 2 includes the steps of: (1) Sequentially placing the inorganic substrate material into absolute ethyl alcohol and deionized water, respectively washing for 20min by ultrasonic waves, and drying; coating a first polysiloxane solution on an inorganic substrate material, drying and curing the inorganic substrate material in a vacuum oven at 100 ℃ for 4 hours, then placing the inorganic substrate material in a muffle furnace, roasting the inorganic substrate material at 550 ℃ for 3 hours, and cooling the inorganic substrate material to room temperature to obtain an intermediate material; (2) And (3) coating a second polysiloxane solution on the intermediate material, and drying and curing the intermediate material in a vacuum oven at the temperature of 100 ℃ for 4 hours to obtain the coalescing material.
The method of making the coalescing material of example 3 includes the steps of: (1) Sequentially placing the inorganic substrate material into absolute ethyl alcohol and deionized water, respectively washing for 20min by ultrasonic waves, and drying; coating a first polysiloxane solution on an inorganic substrate material, drying and curing the inorganic substrate material in a vacuum oven at 105 ℃ for 4 hours, then placing the inorganic substrate material in a muffle furnace, roasting the inorganic substrate material at 550 ℃ for 3 hours, and cooling the inorganic substrate material to room temperature to obtain an intermediate material; (2) And (3) coating a second polysiloxane solution on the intermediate material, and drying and curing the intermediate material in a vacuum oven at 105 ℃ for 3.5 hours to obtain the coalescing material.
The method of making the coalescing material of example 4 includes the steps of: (1) Sequentially placing the inorganic substrate material into absolute ethyl alcohol and deionized water, respectively ultrasonically washing for 25min and 15min, and drying; coating a first polysiloxane solution on an inorganic substrate material, drying and curing the inorganic substrate material in a vacuum oven at 105 ℃ for 4 hours, then placing the inorganic substrate material in a muffle furnace, roasting the inorganic substrate material at 550 ℃ for 4 hours, and cooling the inorganic substrate material to room temperature to obtain an intermediate material; (2) And (3) coating a second polysiloxane solution on the intermediate material, and drying and curing the intermediate material in a vacuum oven at 105 ℃ for 4 hours to obtain the coalescing material.
The method of making the coalescing material of example 5 includes the steps of: (1) Sequentially placing the inorganic substrate material into absolute ethyl alcohol and deionized water, respectively ultrasonically washing for 25min and 15min, and drying; coating a first polysiloxane solution on an inorganic substrate material, drying and curing the inorganic substrate material in a vacuum oven at 105 ℃ for 5 hours, then placing the inorganic substrate material in a muffle furnace, roasting the inorganic substrate material at 550 ℃ for 4 hours, and cooling the inorganic substrate material to room temperature to obtain an intermediate material; (2) And (3) coating a second polysiloxane solution on the intermediate material, and drying and curing the intermediate material in a vacuum oven at 105 ℃ for 4 hours to obtain the coalescing material.
Example 1 of oil removal test
The experimental conditions in example 1 are as follows:
inorganic base material: a copper mesh with a pore size of 87 μm;
first polysiloxane solution: the mass ratio of the aminopropyl double-end-capped polydimethylsiloxane to the curing agent (tetraethoxysilane) to the tetrahydrofuran to the deionized water is 1:0.1:8.9:23.3;
coating method of first polysiloxane solution to inorganic substrate material: spraying;
second polysiloxane solution: the mass ratio of the aminopropyl double-end-capped polydimethylsiloxane to the curing agent (aminopropyl triethoxysilane) to the tetrahydrofuran to the deionized water is 1:0.1:36.4:87.5;
the method for coating the intermediate material by the second polysiloxane solution comprises the following steps: and (5) spraying.
The produced coalescence material was packed into a tank type oil-water separator, and the thickness of the coalescence material bed layer was 210mm, and the oil removal effect of the coalescence material on the electric desalting drain water was evaluated. For the electric desalting drainage water containing 1500mg/L of oil (pH is 8.95, COD is 4314.6 mg/L), the petroleum mass concentration of the discharged water is 157.5mg/L, and the oil removal rate reaches 89.5%.
Example 2 of oil removal test
The experimental conditions in example 2 are as follows:
inorganic base material: stainless steel wire mesh with aperture of 62 μm;
first polysiloxane solution: the mass ratio of the hydroxyl-terminated polydimethylsiloxane to the curing agent (tetraethoxysilane) to the tetrahydrofuran to the deionized water is 1:0.1:5:13.9;
coating method of first polysiloxane solution to inorganic substrate material: dipping-lifting;
second polysiloxane solution: the mass ratio of the hydroxyl-terminated polydimethylsiloxane to the curing agent (tetraethoxysilane) to the tetrahydrofuran to the deionized water is 1:0.1:28.9:70;
the method for coating the intermediate material by the second polysiloxane solution comprises the following steps: and (5) spraying.
The resulting sample of coalescing material was characterized using scanning electron microscopy. As can be seen from the electron microscope images (figures 1-4), a certain amount of bulges are deposited on the surface and nodes of the stainless steel wire, and the bulges are SiO generated by the high-temperature roasting degradation of polysiloxane 2 And (3) particles. SiO (SiO) 2 The particles construct a micro/nano structure on the surface of the substrate material, and the roughness of the surface of the substrate material is increased. In the final preparation step, the polysiloxane is coated on the deposited SiO 2 Forming polysiloxane coated SiO on the surface of the substrate material 2 Organic-inorganic composite coating of particles. Under the synergistic effect of the low surface energy and high roughness of the composite coating, the contact angle of the water drop on the surface of the coalescence material sample is 128.5 ° (see fig. 5); whereas oil droplets can wet spread rapidly on the surface of the coalescing material with contact angles approaching 0 ° (see fig. 6).
The obtained coalescence material is filled into a tank type oil-water separator, the thickness of the coalescence material bed layer is 420mm, and the oil removal effect of the coalescence material on electric desalting drainage is evaluated. For electric desalting drainage (pH is 8.54, COD is 4486.2 mg/L) containing 1530mg/L of oil, the petroleum mass concentration of the effluent is stabilized to be 23.5mg/L, and the oil removal rate reaches 98.5%.
Example 3 oil removal test
The experimental conditions in example 3 are as follows:
inorganic base material: 300 mesh titanium mesh (pore size 44 μm);
first polysiloxane solution: the mass ratio of the hydroxyl-terminated polydimethylsiloxane to the curing agent (aniline methyltriethoxysilane), the tetrahydrofuran to the deionized water is 1:0.1:7.5:16.4;
coating method of first polysiloxane solution to inorganic substrate material: spin coating;
second polysiloxane solution: the mass ratio of the hydroxyl-terminated polydimethylsiloxane to the curing agent (aniline methyltriethoxysilane), the tetrahydrofuran to the deionized water is 1:0.1:28.9:70;
the method for coating the intermediate material by the second polysiloxane solution comprises the following steps: dip-pull.
The obtained coalescence material is filled into a tank type oil-water separator, the thickness of the coalescence material bed layer is 420mm, and the oil removal effect of the coalescence material on electric desalting drainage is evaluated. For the electric desalting drainage water containing 1500mg/L of oil (pH is 8.95, COD is 4314.6 mg/L), the petroleum mass concentration of the discharged water is 46.4mg/L, and the oil removal rate reaches 96.9%.
Example 4 oil removal test
The experimental conditions in example 4 are as follows:
inorganic base material: stainless steel mesh of 1000 mesh (pore size 13 μm);
first polysiloxane solution: the mass ratio of the hydroxyl-terminated polydimethylsiloxane to the curing agent (aminopropyl triethoxysilane) to the tetrahydrofuran to the deionized water is 1:0.1:5:13.9;
coating method of first polysiloxane solution to inorganic substrate material: dipping-lifting;
second polysiloxane solution: the mass ratio of the hydroxyl-terminated polydimethylsiloxane to the curing agent (tetraethoxysilane) to the tetrahydrofuran to the deionized water is 1:0.1:28.9:70;
the method for coating the intermediate material by the second polysiloxane solution comprises the following steps: and (5) spraying.
And filling the prepared coalescence material into a tank type oil-water separator, wherein the thickness of the coalescence material bed layer is 300mm, and evaluating the oil removal effect of the coalescence tower top condensed water. For the coke-top condensed water (pH 8.26, COD 9068.0 mg/L) containing 2383mg/L of oil, the petroleum mass concentration of the effluent is 106.4mg/L, and the oil removal rate is 95.5%.
Example 5 oil removal test
The experimental conditions in example 5 are as follows:
inorganic base material: 2000 mesh stainless steel wire mesh (pore size 6 μm);
first polysiloxane solution: the mass ratio of the hydroxyl-terminated polydimethylsiloxane to the curing agent (tetraethoxysilane) to the tetrahydrofuran to the deionized water is 1:0.1:5:13.9;
coating method of first polysiloxane solution to inorganic substrate material: dipping-lifting;
second polysiloxane solution: the mass ratio of the hydroxyl-terminated polydimethylsiloxane to the curing agent (tetraethoxysilane) to the tetrahydrofuran to the deionized water is 1:0.1:28.9:70;
the method for coating the intermediate material by the second polysiloxane solution comprises the following steps: and (5) spin coating.
And filling the prepared coalescence material into a tank type oil-water separator, wherein the thickness of the coalescence material bed layer is 300mm, and evaluating the oil removal effect of the coalescence material on oilfield produced water. For oil field produced water (pH is 8.21, COD is 2644.2 mg/L) containing 1000mg/L of oil, the mass concentration of petroleum in the produced water is 17.0mg/L, and the oil removal rate is 98.3%.
While the embodiments of the present invention have been described in detail with reference to the examples, it should be noted that the scope of the present invention is not limited by the embodiments, but is defined by the appended claims. Those skilled in the art can make appropriate modifications to these embodiments without departing from the technical spirit and scope of the present invention, and it is apparent that these modified embodiments are also included in the scope of the present invention.
Claims (25)
1. A coalescing material comprising: a base material; siO deposited on the surface of the substrate material 2 Particles; coating the SiO 2 A polysiloxane on the surfaces of the particles and the substrate material; the substrate material is a metal material;
the preparation method of the coalescing material comprises the following steps:
(1) Coating a first polysiloxane solution on a substrate material, drying and solidifying the substrate material at 80-130 ℃, roasting the substrate material at 400-600 ℃ for 2-4 hours, and cooling the substrate material to 0-35 ℃ to obtain an intermediate material;
(2) And coating a second polysiloxane solution on the intermediate material, and drying and curing at 80-130 ℃.
2. The coalescing material of claim 1, wherein the base material is one or more of a wire mesh, a metal sheet, and a metal disc.
3. The coalescing material of claim 1, wherein the base material is a wire mesh having a pore size of 3 to 90 μm.
4. The coalescing material of claim 1, wherein the polysiloxane has a structure according to formula (I):
wherein n is an integer between 1 and 1400; each R group is independently selected from C 1 ～C 8 Alkyl, C of (2) 1 ～C 2 Alkoxy, C 1 ～C 3 Haloalkyl, C 2 ～C 5 Alkenyl, phenyl;
wherein the A group is selected from H,Wherein each R group is independently selected from C 1 ～C 3 Alkyl, C of (2) 1 ～C 3 Each R' group is independently selected from H, C 1 ～C 3 The R' group is selected from C 1 ～C 6 An alkylene group of (a);
wherein the A' group is selected from OH,Wherein each R' group is independently selected from H, C 1 ～C 3 Alkyl of (a); each R' group is independently selected from C 1 ～C 6 Alkylene groups of (a).
5. The coalescing material of claim 4, wherein n is an integer between 100 and 1200; each R group is independently selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, methoxy, ethoxy, trifluoropropyl, vinylPhenyl; wherein the A group is selected from H,Wherein each R group is independently selected from methyl, methoxy, ethyl, ethoxy, propyl, propoxy, each R 'group is independently selected from H, methyl, and each R' group is selected from C 1 ～C 4 An alkylene group of (a);
wherein the A' group is selected from OH,Wherein each R' group is independently selected from H, methyl; each R' group is independently selected from C 1 ～C 4 Alkylene groups of (a).
6. The coalescing material of claim 4, wherein n is an integer between 140 and 1000; each R group is independently selected from methyl;
wherein the A group is selected from H,Wherein each R group is independently selected from methyl, each R 'group is independently selected from H, R' methylene, ethylene, propylene, butylene;
wherein the A' group is selected from OH,Wherein each R' group is independently selected from H; each R "group is independently selected from methylene, ethylene, propylene, butylene.
7. The coalescing material of claim 1, wherein the polysiloxane is a polysiloxane of formula (II) and/or formula (III):
wherein n is each independently an integer between 1 and 1400; each R group is independently selected from C 1 ～C 8 Alkyl, C of (2) 1 ～C 2 Alkoxy, C 1 ～C 3 Haloalkyl, C 2 ～C 5 Alkenyl, phenyl; each R' group is independently selected from H, C 1 ～C 3 Each R' group is selected from C 1 ～C 6 Alkylene groups of (a).
8. The coalescing material of claim 7, wherein n is each independently an integer between 100 and 1200; each R group is independently selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, methoxy, ethoxy, trifluoropropyl, vinyl, phenyl; each R 'group is independently selected from H, methyl, each R' group is selected from C 1 ～C 4 Alkylene groups of (a).
9. The coalescing material of claim 7, wherein each n is independently an integer between 140 and 1000; each R group is independently selected from methyl; each R' group is independently selected from H and each R "group is selected from methylene, ethylene, propylene, butylene.
10. A method of preparing the coalescing material of any one of claims 1 to 9, comprising:
(1) Coating a first polysiloxane solution on a substrate material, drying and solidifying the substrate material at 80-130 ℃, roasting the substrate material at 400-600 ℃ for 2-4 hours, and cooling the substrate material to 0-35 ℃ to obtain an intermediate material; the substrate material is a metal material;
(2) And coating a second polysiloxane solution on the intermediate material, and drying and curing at 80-130 ℃.
11. The method of claim 10, wherein the solute of the polysiloxane solution is polysiloxane and a curing agent, and the curing agent is a silicone curing agent.
12. The method according to claim 11, wherein the curing agent is one or more of phenylmethyltriethoxysilane, tetraethyl orthosilicate, and aminopropyl triethoxysilane.
13. The method according to claim 10, wherein the solvent of the polysiloxane solution is one or more of tetrahydrofuran, n-hexane, n-heptane, a mixture of tetrahydrofuran and water.
14. The method according to claim 10, wherein the solvent of the polysiloxane solution is tetrahydrofuran or a mixture of tetrahydrofuran and deionized water.
15. The method according to claim 10, wherein the concentration of the solute in the polysiloxane solution is 0.2% to 10% by mass.
16. The method according to claim 10, wherein the concentration of the solute in the polysiloxane solution is 0.3% to 7% by mass.
17. The method of claim 10, wherein the first polysiloxane solution has a solute mass concentration of 1.8% to 10%; the mass concentration of the solute in the second polysiloxane solution is 0.2% -2%.
18. The method of claim 10, wherein the first polysiloxane solution has a solute mass concentration of 2% to 7%; the mass concentration of the solute in the second polysiloxane solution is 0.5% -1.7%.
19. The method of claim 10, wherein the solute in the first polysiloxane solution is a mixture of polysiloxane and curing agent, and the solvent is a mixture of tetrahydrofuran and deionized water, wherein the mass ratio of polysiloxane, curing agent, tetrahydrofuran and deionized water is 1: 0.095-0.105: 5 to 14:10 to 35; the solute in the second polysiloxane solution is a mixture of polysiloxane and curing agent, and the solvent is a mixture of tetrahydrofuran and deionized water, wherein the mass ratio of polysiloxane, curing agent, tetrahydrofuran and deionized water is 1: 0.095-0.105: 18 to 59: 46-140.
20. The method of preparing according to claim 10, wherein the method of applying the polysiloxane solution to the base material or the intermediate material comprises one or more of dip-pull, spray coating, and spin coating.
21. The method of claim 10, wherein the substrate material is subjected to a cleaning pretreatment prior to applying the first polysiloxane solution to the surface of the substrate material.
22. The method of claim 10, wherein the substrate is subjected to an ultrasonic cleaning pretreatment in a cleaning liquid prior to applying the first polysiloxane solution to the surface of the substrate.
23. The process according to claim 10, wherein the drying and curing in step (1) are carried out at a temperature of 90 to 125℃for 0.3 to 6 hours; the temperature of drying and curing in the step (2) is 90-125 ℃, and the time of drying and curing is 0.3-6 h.
24. The process according to claim 10, wherein the drying and curing in step (1) are carried out at a temperature of 95 to 110℃for 3 to 5 hours; the temperature of drying and curing in the step (2) is 95-110 ℃, and the time of drying and curing is 0.3-6 h.
25. The use of the coalescing material of any one of claims 1 to 9 or the coalescing material made according to the method of any one of claims 10 to 24 as a coalescing oil removal material.
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