CN108434788A - A kind of separation method of oil hydrosol - Google Patents

Abstract

The present invention relates to a kind of separation methods of oil hydrosol.It is reacted using freezing polymerization, by polyethyleneglycol diacrylate, mixing goes in syringe and seals after being passed through nitrogen deoxygenation in poly- divinylbenzene particle and initiator to solvent, and controlling reaction temperature is reacted 48 hours at 18 DEG C；Products therefrom is after eluting solvent fully washs, and under only with gravity, is detached for oil hydrosol, and water-oil separating efficiency is up to 99.8%, and oil content is less than 50ppm in water, and polymer material is higher than 2.8g/g to the adsorption capacity of oil hydrosol.Preparation method of the present invention is simple and reliable, and post-processing is simple, and resulting materials are used for the separation of oil hydrosol, and separating rate is fast, and separative efficiency is high, and recycling rate of waterused is good, and adsorption capacity is big.

Description

A kind of separation method of oil-water emulsion

technical field

The invention relates to a method for separating an oil-water emulsion, which belongs to the technical field of emulsion separation.

Background technique

Oily wastewater exists widely in all aspects of human life, from oil exploration and product development, to the impact of various types of oil spills and marine oil spills on the human living environment, from industrial wastewater discharge to human daily life. Various wastewaters pose a threat to human health. The development of materials and processes with high-efficiency separation capabilities for oily wastewater has broad application value.

According to the form of oil-water composition, oily wastewater can be simply divided into two types: oil-water mixture and oil-water emulsion. At present, a large number of effective methods have been reported for the separation of oil-water mixtures, and various high-efficiency oil-water separation materials have been developed. Most of these oil-water separation materials are hydrophobic or even superhydrophobic. For example: Chinese patent document CN103203226A discloses a graphite powder-butyl rubber composite cryogel oil-absorbing material and a preparation method thereof. The obtained porous material can quickly absorb various oil substances, and the oil absorption ratio is close to 20. Chinese patent document CN106432563A discloses a super-macroporous polymer prepared from a hydrophobic monomer divinylbenzene, and the obtained material has an adsorption ratio of more than 30 for crude oil. However, the separation of oil-water emulsions by the above materials is difficult, mainly because a large amount of surfactants are attached to the surface of oil-water emulsions, which can be uniformly and stably distributed in the water phase, and are not easily adsorbed or absorbed by hydrophobic materials.

Compared with the separation of oil-water mixture, the separation process of oil-water emulsion should include at least two processes of demulsification and oil-water separation. In specific industrial practice, due to the complex composition of oil-water emulsion, the separation process usually requires demulsification-coagulation/gas Flotation/adsorption-separation and other methods of synergy can be realized, which is the difficulty of oil-water emulsion separation. For example: Chinese patent document CN1206178C discloses a treatment method for high-concentration emulsified oil wastewater. It first uses a grease trap to remove the upper layer of slick oil, and then sequentially passes through steps such as demulsification, air flotation, electrolysis and biochemical treatment to complete the treatment of oil-water emulsion. separate. This kind of multi-method coordinated process is relatively complicated, time-consuming and inefficient. In recent years, people have begun to use some materials with special interfacial wettability in the separation of oil-water emulsions. For example: Chinese patent document CN104548667A discloses a kind of omentum for the separation of oil-water emulsion and its preparation method, it will have the metal oxide of micro-nano structure to be attached to the mesh of metal mesh and net line to form composite omentum structure . The obtained composite omentum has properties of superhydrophilic and superoleophilic in air, superhydrophobic under oil, and superoleophobic under water, and can realize rapid separation of oil-water emulsion. However, the application of continuous large-scale oil-water emulsion separation is limited due to the usually small adsorption capacity of the separation membrane.

Contents of the invention

Aiming at the problems and deficiencies in the above-mentioned prior art, the present invention provides a method for separating oil-water emulsion. The present invention adopts the composite ultra-macroporous polymer material with special interfacial wetting properties to separate oil-water emulsion; Under pore formation, it is prepared in situ by freeze polymerization at a lower temperature. It has the properties of superhydrophilic and superoleophilic in the air, superhydrophilic under oil, and oleophobic under water. It can realize oil-water emulsion only under the action of gravity. quick separation.

Technical scheme of the present invention is:

A method for separating oil-water emulsion, the steps are as follows:

After the composite ultra-macroporous polymer is swollen with water and balanced, the oil-water emulsion to be separated is added, and the oil-water emulsion is separated by gravity;

The composite ultra-macroporous polymer is prepared as follows:

Add the hydrophilic monomer polyethylene glycol diacrylate, the hydrophobic polymer particle polydivinylbenzene, and the initiator to the solvent and mix well, pass nitrogen gas to remove oxygen and seal it, and control the reaction temperature at -40°C~ React at 4°C for 12 to 96 hours. After the product is fully washed with an elution solvent, it is dried to obtain a composite ultra-macroporous polymer.

According to the present invention, preferably, the mass ratio of polyethylene glycol diacrylate to polydivinylbenzene is 1:(0.1-1.0), more preferably 1:(0.2-0.5).

According to the present invention, preferably, the number average molecular weight of the polyethylene glycol diacrylate is 258-700, and the average particle diameter of the polydivinylbenzene is 4 μm.

According to the present invention, preferably, the initiator is a redox initiation system composed of benzoyl peroxide and N,N-dimethylaniline;

Preferably, the solvent is one or a combination of water, lauryl alcohol, dimethyl sulfoxide and acetic acid;

Preferably, the initiator accounts for 0.5-10% by weight of polyethylene glycol diacrylate;

Preferably, the eluting solvent is ethanol.

According to the present invention, preferably, the reaction temperature is between -20°C and 4°C; the reaction time is 20 to 50 hours.

According to the present invention, the oil-water emulsion refers to an oil-water emulsion that does not contain a surfactant or an oil-water emulsion that contains a surfactant (such as Tween 80).

According to the separation method of the oil-water emulsion of the present invention, a preferred embodiment is as follows;

Put the composite ultra-macroporous polymer in a columnar container, add water to swell and balance, add the oil-water emulsion from the upper part of the columnar container, rely on gravity, the oil-water emulsion flows through the polymer material, and the oil-water emulsion is demulsified when flowing through the column material, and the water It can pass through the polymer material smoothly, but the oil is retained in the polymer material, so as to realize the separation of oil-water emulsion.

According to the invention, the composite ultra-macroporous polymer material can be reused after being fully washed with ethanol. After repeated use for more than 8 times, the oil-water separation efficiency remains above 99.5%.

According to the present invention, a preferred embodiment of the preparation of the composite ultra-macroporous polymer is as follows:

Add 0.5mL of polyethylene glycol diacrylate, 250mg of polydivinylbenzene particles, 4.8μl of N,N-dimethylaniline and 9.2mg of benzoyl peroxide into 9.5ml of dimethyl sulfoxide and mix well , after passing through nitrogen to remove oxygen, transfer to a syringe to seal, control the reaction temperature at -18°C, and react for 48 hours; the obtained product is fully washed with an elution solvent, and dried to obtain a composite ultra-macroporous polymer.

Features and beneficial effects of the present invention are as follows:

1. The composite ultra-macroporous polymer material of the present invention has a micron-scale ultra-macroporous structure, and its pore diameter range is mainly distributed between 1 and 100 μm. Oleophobic properties, suitable for the separation of oil-water emulsion, the separation process can be carried out only by gravity, without external pressure device, the oil-water separation efficiency is higher than 99.5%, the oil content in water is lower than 50ppm, and the polymer material can absorb the oil-water emulsion The capacity is higher than 2.8g/g.

2. The method of the present invention is simple and reliable, and the post-treatment is simple. The obtained material is used for the separation of oil-water emulsion, the separation speed is high, the oil-water separation efficiency is high, the recycling rate is high, and the adsorption capacity is large, which is superior to the prior art.

Description of drawings

Figure 1: SEM image of the ultra-macroporous polymer material prepared in Comparative Example 1.

Fig. 2: The scanning electron micrograph of the composite ultra-macroporous polymer material prepared in Example 1.

Figure 3: Schematic diagram of the oil-water emulsion separation process in Example 1.

Figure 4: The recycling performance diagram of the composite ultra-macroporous polymer material prepared in Example 1 for oil-water emulsion separation.

Detailed ways

The present invention will be further described below through specific embodiments in conjunction with the accompanying drawings, but is not limited thereto.

Example 1

Take 0.180mL (200mg) of polyethylene glycol diacrylate (number average molecular weight 600), 100mg polydivinylbenzene particles (average particle size 4μm), 0.5μL N,N-dimethylaniline and 1.0mg peroxide Benzoyl was added to 1.1 mL of dimethyl sulfoxide and mixed evenly. After passing through nitrogen to deoxygenate, it was transferred to a syringe and sealed. The reaction temperature was controlled at -18°C and reacted for 48 hours. The obtained product is fully washed with the elution solvent ethanol, and then dried to obtain a composite ultra-macroporous polymer.

The scanning electron microscope image of the composite ultra-macroporous polymer prepared in this example is shown in FIG. 2 , and the schematic diagram of the oil-water emulsion separation process is shown in FIG. 3 .

Put the obtained composite ultra-macroporous polymer material in a syringe, add water to swell and balance for 2 hours, add 1mL oil-water emulsion from the upper part of the column tube, and the oil-water emulsion can flow through the polymer column material only by gravity, and the water can pass through the polymer column smoothly. material, it takes 1 minute, while the oil is retained in the column material, and the oil-water separation efficiency is 99.8%.

After the polymer material is fully washed with ethanol and used repeatedly for more than 10 times, the oil-water separation efficiency is not less than 99.5%. The recycling performance is shown in Figure 4. It can be seen that the composite ultra-macroporous polymer of the present invention has good recycling performance.

Example 2

Take 0.36mL (400mg) of polyethylene glycol diacrylate (number average molecular weight 600), 40mg polydivinylbenzene particles (average particle size 4μm), 0.2μL N,N-dimethylaniline and 0.4mg peroxide Benzoyl was added to 1.6 mL of dimethyl sulfoxide and mixed well. After passing through nitrogen to deoxygenate, it was transferred to a syringe and sealed. The reaction temperature was controlled at -18°C and reacted for 48 hours. The obtained product is fully washed with the elution solvent ethanol, and then dried to obtain a composite ultra-macroporous polymer.

Put the obtained composite ultra-macroporous polymer material in a syringe, add water to swell and balance for 2 hours, add 1mL oil-water emulsion from the upper part of the column tube, and the oil-water emulsion can flow through the polymer column material only by gravity, and the water can pass through the polymer column smoothly. material, it takes 1 minute, while the oil is retained in the column material, and the oil-water separation efficiency is 98.3%.

Example 3

Take 0.135mL (150mg) of polyethylene glycol diacrylate (number average molecular weight 600), 150mg polydivinylbenzene particles (average particle size 4μm), 0.8μl N,N-dimethylaniline and 1.5mg peroxide Benzoyl was added to 1.09 mL of dimethyl sulfoxide and mixed evenly. After passing through nitrogen to deoxygenate, it was transferred to a syringe and sealed. The reaction temperature was controlled at -18°C and reacted for 48 hours. The obtained product is fully washed with the elution solvent ethanol, and then dried to obtain a composite ultra-macroporous polymer.

Put the obtained composite ultra-macroporous polymer material in a syringe, add water to swell and balance for 2 hours, add 1mL oil-water emulsion from the upper part of the column tube, and the oil-water emulsion can flow through the polymer column material only by gravity, and the water can pass through the polymer column smoothly. material, it takes 1 minute, while the oil is retained in the column material, and the oil-water separation efficiency is 93.9%.

Comparative example 1

Take 0.363mL (0.403mg) of polyethylene glycol diacrylate (the number average molecular weight is 600), 2.1μL of N,N-dimethylaniline and 4.0mg of benzoyl peroxide were added to 1.45mL of dimethyl methoxide Mix well in sulfone, pass through nitrogen to deoxygenate, transfer to a syringe to seal, control the reaction temperature at -18°C, and react for 48 hours. The obtained product is fully washed with the elution solvent ethanol, and then dried to obtain a composite ultra-macroporous polymer.

Put the obtained polyethylene glycol diacrylate super-macroporous polymer material in a syringe, add water to swell and balance for 2 hours, add 1mL oil-water emulsion from the upper part of the column tube, and the oil-water emulsion can flow through the polymer column material only by gravity, It takes 5 minutes for water to pass through the polymeric column material, while oil is retained in the column material, and the oil-water separation efficiency is 83.5%.

The scanning electron micrograph of the ultra-macroporous polymer prepared in this comparative example is shown in Figure 1. Since no polydivinylbenzene particles are added, the oil-water separation efficiency of the ultra-macroporous polymer obtained will be seriously reduced.

Comparative example 2

Take 0.090mL (100mg) of polyethylene glycol diacrylate (number average molecular weight 600), 200mg polydivinylbenzene particles (average particle size 4μm), 1.0μl N,N-dimethylaniline and 2.0mg peroxide Benzoyl was added to 1.09 mL of dimethyl sulfoxide and mixed evenly. After passing through nitrogen to deoxygenate, it was transferred to a syringe and sealed. The reaction temperature was controlled at -18°C and reacted for 48 hours. The obtained product is fully washed with the elution solvent ethanol, and then dried to obtain a composite ultra-macroporous polymer.

Put the obtained composite ultra-macroporous polymer material in a syringe, add water to swell and balance for 2 hours, add 1mL of oil-water emulsion from the upper part of the column tube, and only rely on gravity, the oil-water emulsion will flow through the polymer column material within 20 seconds, and the oil-water emulsion will There is no obvious change before and after flowing through the composite material, and the oil-water separation efficiency is lower than 5%.

In this comparative example, the mass ratio of polyethylene glycol diacrylate to polydivinylbenzene is 1:2, that is, the amount of polydivinylbenzene particles added is too much, and the composite ultra-macroporous polymer produced has almost no oil-water emulsion. ability to separate.

Claims (10)

1. a kind of separation method of oil hydrosol, including steps are as follows：

After compound super large pore polymer is added water-swellable balance, oil hydrosol to be separated is added, relies on gravity, to oil Aqueous emulsion is detached；

The compound super large pore polymer is prepared as follows to obtain：

Hydrophilic monomer polyethyleneglycol diacrylate, hydrophobic polymer granule polydivinylbenezene, initiator are added to Mixing in solvent seals after being passed through nitrogen deoxygenation, and controlling reaction temperature is reacted 12~96 hours between -40 DEG C~4 DEG C, production Object is dry to get compound super large pore polymer after eluting solvent fully washs.

2. the separation method of oil hydrosol according to claim 1, which is characterized in that the polyethylene glycol diacrylate The mass ratio of ester and polydivinylbenezene is 1：(0.1-1.0).

3. the separation method of oil hydrosol according to claim 1, which is characterized in that the polyethylene glycol diacrylate The number-average molecular weight of ester is 258-700.

4. the separation method of oil hydrosol according to claim 1, which is characterized in that the initiator is benzoyl peroxide Formyl and N, the redox initiation system of accelerine composition.

5. the separation method of oil hydrosol according to claim 1, which is characterized in that the solvent be water, lauryl alcohol, One or both of dimethyl sulfoxide (DMSO) and acetic acid combine.

6. the separation method of oil hydrosol according to claim 1, which is characterized in that the initiator accounts for polyethylene glycol The weight percent of diacrylate is between 0.5~10%.

7. the separation method of oil hydrosol according to claim 1, which is characterized in that the eluting solvent is ethyl alcohol.

8. the separation method of oil hydrosol according to claim 1, which is characterized in that the reaction temperature is at -20 DEG C Between~4 DEG C；20~50 hours reaction time.

9. the separation method of oil hydrosol according to claim 1, which is characterized in that the separation method of oil hydrosol, packet Include that steps are as follows：

Compound super large pore polymer is placed in column shape container, after adding water-swellable balance, grease is added from column shape container top Lotion relies on gravity, and oil hydrosol flows through polymer material, and oil hydrosol is demulsified when flowing through column material, and water can be with Polymer material is passed through, oil is but retained in the polymeric material, to realize the separation of oil hydrosol.

10. the separation method of oil hydrosol according to claim 1, which is characterized in that the compound super big hole is poly- The preparation of object is closed, including steps are as follows：

Take the polyethyleneglycol diacrylate of 0.5mL, the poly- divinylbenzene particles of 250mg, 4.8 μ l n,N-Dimethylaniline and 9.2mg benzoyl peroxides are added to mixing in the dimethyl sulfoxide (DMSO) of 9.5ml, after being passed through nitrogen deoxygenation, go to close in syringe Envelope, controlling reaction temperature are reacted 48 hours at -18 DEG C；Products therefrom is dry after eluting solvent fully washs, and obtains compound Type super large pore polymer.