JP2550262B2 - Oil absorbent - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an oil absorbent. More specifically, the present invention relates to an oil absorbing agent which absorbs a large amount of oil to a wide variety of oils even from an oil / water mixed system and swells, has excellent oil retaining performance of the absorbed oil, and has a significantly improved oil absorbing speed.

[0002]

2. Description of the Related Art In recent years, the recovery of oil spilled into the sea and oil in waste water has become a major environmental issue. Further, there is a strong demand for a simple method for treating leaked oil such as small-scale waste oil discarded in homes and factories and machine oil in factories.

[0003] As one of the effective means for recovering these oil spills and oil components in waste water or treating waste oil and oil leaks, a method of adsorbing oil with an oil absorbent and then incineration or other post-treatment has been conventionally used. Has been. As such an oil absorbing material,
For example, a synthetic fiber oil absorbing material made of a hydrophobic fiber such as polypropylene fiber, polystyrene fiber, polyethylene fiber or a nonwoven fabric thereof has been used. However, the conventional synthetic fiber-based oil absorbent material is inferior in oil retention performance after oil absorption because the oil absorbing action is due to adsorption and holding of the oil in the voids existing in the oil absorbent material due to the capillary phenomenon, so that it is less than the low viscosity oil. Has substantially no oil retaining ability, and since the oil that was easily absorbed is re-released even with viscous oil with a slight external pressure, liquid sagging easily occurs and post-treatment becomes extremely complicated. Was. Also, when applied to the recovery of oil content of oil-water mixed system or thin film oil floating on the water surface, the recovery rate of oil is poor and a large amount of water is absorbed, so the oil absorbing material sinks in water and is difficult to recover. However, there is a problem in that combustion after recovery is inconvenient.

As means for solving these problems, some synthetic resin type oil absorbents of the type in which oil is absorbed and swelled in a certain polymer have been reported. For example,
A copolymer of t-butylstyrene / divinylbenzene (JP-A-45-27081), a cross-linked polymer of t-butyl methacrylate and / or neopentyl methacrylate (JP-A-50-15882), and menthyl methacrylate of Cross-linked polymer (JP-A-50-59486), polynorbornene rubber (for example, Nosolex AP manufactured by CdF), and cross-linked polymer of alkyl (meth) acrylate having 10 to 16 carbon atoms (JP-A-3-221).
582) and the like. These oil-absorbing agents have an oil-absorption function because they absorb oil into the molecule having a hydrophobic structure and swell, so that only oil is added to the oil content of oil-water mixed systems and thin-film oil floating on the water surface. Absorbs selectively,
Moreover, it has advantages such as excellent oil retaining ability for oil once absorbed.

However, these synthetic resin-based oil absorbents have the drawback that the time required for oil absorption is extremely long as compared with synthetic fiber oil absorbents, and in particular, they have a low oil absorption rate for highly viscous oils. There was a problem.

Therefore, in order to improve the oil absorption speed, measures have been taken to increase the surface area of these oil absorbents by processing these oil absorbents into fine particles. However, as the oil-absorbing agent becomes finer, the particles tend to agglomerate with each other, so that the actually expected sufficient oil-absorption rate has not been obtained. Therefore, these oil absorbing agents have a drawback that they are difficult to be applied to the field in which it is required to absorb the oil in a short time, such as when an oil spill accident occurs.

[0007]

DISCLOSURE OF THE INVENTION The present invention solves the above problems of conventional oil absorbing materials (agents). That is, the object of the present invention is to absorb a large amount of oil to a wide variety of oils even from an oil-water mixed system and swell, and the oil absorption performance of the absorbed oil is excellent, and the oil absorption speed is remarkably improved. To provide the agent.

[0008]

The present inventors have found that the above object can be achieved by mixing and complexing a specific oil-absorbing crosslinked polymer and a specific organic acid metal salt, and It came to completion.

That is, according to the present invention, the monomers (A) 96 to 9 having one polymerizable unsaturated group in the molecule whose main component is a monomer having a solubility parameter (SP value) of 9 or less.
9.999% by weight and 0.001 to 4 crosslinkable monomer (B) having at least two polymerizable unsaturated groups in the molecule
% By weight (however, the sum of monomers (A) and (B) is 10
30 to 99 parts by weight and 20 of an oil-absorptive cross-linked polymer (I) obtained by polymerizing a monomer component consisting of
The present invention relates to an oil absorbent containing 1 to 70 parts by weight of an organic acid metal salt (II) having a solubility of 1 g or less in 100 g of water at 0 ° C.

[0010]

The solubility parameter (SP value) is generally used as a measure of the polarity of a compound, and in the present invention, the value derived by substituting the Hoy cohesive energy constant into the Small calculation formula is applied. And the unit (cal /
expressed in cm ^{3) 1/2.}

The monomer constituting the main component of the monomer (A) used in the present invention is a monomer having a solubility parameter (SP value) of 9 or less and having one polymerizable unsaturated group in the molecule. If a monomer having a solubility parameter (SP value) of more than 9 is used as the main component of the monomer (A), only a crosslinked polymer having insufficient oil absorption performance can be obtained, which is not preferable.

Examples of the monomer having a solubility parameter (SP value) of 9 or less and having one polymerizable unsaturated group in the molecule include, for example, methyl (meth) acrylate, ethyl (meth) acrylate and butyl (meth). Acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate,
Dodecyl (meth) acrylate, stearyl (meth) acrylate, phenyl (meth) acrylate, octylphenyl (meth) acrylate, nonylphenyl (meth) acrylate, dinonylphenyl (meth) acrylate, cyclohexyl (meth) acrylate, menthyl (meth) Unsaturated carboxylic acid esters such as acrylate, isobornyl (meth) acrylate, dibutyl maleate, didodecyl maleate, dodecyl crotonate, didodecyl itaconate; (di) butyl (meth) acrylamide, (di) dodecyl (meth) acrylamide ,
(Meth) acrylamide having a hydrocarbon group such as (di) stearyl (meth) acrylamide, (di) butylphenyl (meth) acrylamide, (di) octylphenyl (meth) acrylamide; 1-hexene, 1-octene, isooctene, Α-Olefins such as 1-nonene, 1-decene, 1-dodecene; alicyclic vinyl compounds such as vinylcyclohexane; allyl ethers having a hydrocarbon group such as dodecyl allyl ether; vinyl caproate, vinyl laurate, palmitic acid Vinyl ester having a hydrocarbon group such as vinyl and vinyl stearate;
Vinyl ether having a hydrocarbon group such as butyl vinyl ether and dodecyl vinyl ether; aromatic vinyl compounds such as styrene, t-butyl styrene, octyl styrene and the like can be mentioned, and one or more of these monomers can be used. You can Among these, as a monomer that gives better oil absorption performance and oil retention performance,
It has at least one aliphatic hydrocarbon group having 3 to 30 carbon atoms, and is alkyl (meth) acrylate, alkylaryl (meth) acrylate, alkyl (meth) acrylamide, alkylaryl (meth) acrylamide,
The monomer (A) containing as a main component at least one unsaturated compound (a) selected from the group consisting of fatty acid vinyl ester, alkylstyrene and α-olefin is particularly preferable.

Such solubility parameter (SP value)
Is 9 or less, the amount used in the monomer (A) is
The proportion is 50% by weight or more, more preferably 70% by weight or more, based on the total amount of the monomer (A). When the amount of the monomer having the solubility parameter (SP value) of 9 or less in the monomer (A) is less than 50% by weight, only a crosslinked polymer having poor oil absorption performance and oil retention performance can be obtained.

Therefore, in the present invention, 5 monomers having a solubility parameter (SP value) of 9 or less are included in the monomer (A).
It is necessary that the content of the solubility parameter (SP) is 50% by weight or less in the monomer (A), although the content of SP is 0% by weight or more.
A monomer having one polymerizable unsaturated group may be contained in a molecule whose value) exceeds 9. Examples of such a monomer include (meth) acrylic acid, acrylonitrile, maleic anhydride, fumaric acid, hydroxyethyl (meth) acrylate, polyethylene glycol (meth) acrylate, and methoxypolyethylene glycol (meth) acrylate. You can

Examples of the crosslinkable monomer (B) used in the present invention include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polyethylene glycol-polypropylene glycol di. (Meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di ( (Meth) acrylate, N, N'-methylenebisacrylamide, N, N '
-Alkylene oxide adducts of propylenebisacrylamide, glycerin tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, polyhydric alcohols (eg glycerin, trimethylolpropane or tetramethylolmethane). Examples thereof include polyfunctional (meth) acrylates and divinylbenzene obtained by esterification with and (meth) acrylic acid, and one or more of these crosslinkable monomers can be used.

The proportions of the monomer (A) and the crosslinkable monomer (B) in the monomer component used for producing the crosslinked polymer (I) are the same as those of the monomer (A) and the crosslinkable monomer. The amount of the monomer (A) is 96 to 99.9 with respect to the total amount of the monomer (B).
99% by weight, the crosslinkable monomer (B) is 0.001-
It is in the range of 4% by weight.

When the amount of the monomer (A) is less than 96% by weight or the amount of the crosslinkable monomer (B) exceeds 4% by weight, the crosslink density of the obtained crosslinked polymer becomes too high and a large amount of oil is obtained. It is not preferable because it cannot be absorbed. Further, the monomer (A) is 9
If it exceeds 9.999% by weight or the crosslinkable monomer (B) is less than 0.9.
If it is less than 001% by weight, the solubility of the resulting crosslinked polymer in oil is increased, and the crosslinked polymer is fluidized after oil absorption and the performance as an oil absorbing agent cannot be obtained, which is not preferable.

The crosslinked polymer (I) in the present invention contains, for example, the above-mentioned monomer components in an aqueous medium as a protective colloid agent such as polyvinyl alcohol, hydroxyethyl cellulose and gelatin, sodium alkylsulfonate, sodium alkylbenzenesulfonate and polyoxy. It can be produced by dispersing it in the presence of a surfactant such as ethylene alkyl ether or fatty acid soap and carrying out suspension polymerization with an oil-soluble radical polymerization initiator. If necessary, the monomer component may be dissolved in a water-insoluble organic solvent and then suspension-polymerized. Examples of the oil-soluble radical polymerization initiator include organic peroxides such as benzoyl peroxide, lauroyl peroxide and cumene hydroperoxide;
An azo compound such as ′ -azobisisobutyronitrile or 2,2′-azobisdimethylvaleronitrile can be used. The polymerization temperature can be appropriately selected within the range of 0 to 150 ° C. depending on the type of monomer component and the type of polymerization initiator.

As a method for producing the crosslinked polymer (I) in the present invention, there is a method of polymerizing the crosslinked polymer (I) by bulk polymerization and then adjusting the particle size by adding an operation such as pulverization. it can. Bulk polymerization is carried out, for example, by pouring a monomer component into a mold in the presence of the above-mentioned polymerization initiator to obtain 50 to 1
The polymerization may be carried out under the condition of 50 ° C.

In the present invention, the cross-linked polymer (I) has an average particle size of 0. 1 by introducing a pre-suspension step using a homomixer or the like during suspension polymerization and adjusting stirring power during polymerization.
It is preferable that the particles are in the range of 5 to 500 μm.
If the average particle size of the particles of the crosslinked polymer (I) is less than 0.5 μm, the surface area decreases due to the Mamako phenomenon based on the aggregation of the particles, making it difficult to obtain an oil absorbent having an improved oil absorption rate. Become. Further, if the average particle size of the particles of the crosslinked polymer (I) exceeds 500 μm, the oil absorption rate also decreases as the surface area of the crosslinked polymer decreases, which is not preferable.

As the organic acid metal salt (II) in the present invention, so-called completely neutralized neutral soap, acidic soap with excess organic acid, and basic soap with excess metal can be used. Moreover, any of monosoap, disoap, and trisoap may be used.

The organic acid constituting the organic acid metal salt (II) is
There is no particular limitation as long as it shows a water-insolubility or poor water-solubility of 1 g or less in 100 g of water at 20 ° C. when forming an organic acid metal salt, and examples thereof include butyric acid, caproic acid, caprylic acid, pelargonic acid, and caprin. Acids, undecanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, montanic acid, linear saturated fatty acids such as mericic acid; oleic acid, linoleic acid, linolenic acid, etc. Straight chain unsaturated fatty acids; branched fatty acids such as isostearic acid; fatty acids containing hydroxyl groups such as ricinoleic acid and 12-hydroxystearic acid; benzoic acid; naphthenic acid; abietic acid, rostroic acid such as dextropimaric acid. It is possible to use one or more of these. Among these organic acids, carbon number 3 to 30
Are preferred.

The metal constituting the organic acid metal salt (II) is not particularly limited as long as it shows the above-mentioned water insolubility or poor water solubility when the organic acid metal salt is formed.
Sodium, potassium, lithium, copper, beryllium, magnesium, calcium, strontium, barium,
Zinc, cadmium, aluminum, cerium, titanium,
Zirconium, lead, chromium, manganese, cobalt, nickel and the like can be mentioned, and one or more of these can be used.

Organic acid metal salt (II) used in the present invention
Preferably has an average particle size of 0.01 to 300 μm. If the average particle size is less than 0.01 μm, the powder particles agglomerate to reduce the oil absorption rate, which is not preferable. Further, if the average particle size exceeds 300 μm, the synergistic effect with the crosslinked polymer (I) is difficult to be exhibited, and the oil absorption rate cannot be improved, which is not preferable.

There are no particular restrictions on the method of mixing the oil-absorbing crosslinked polymer (I) and the organic acid metal salt (II) in the production of the oil absorbent of the present invention, and either wet mixing or dry mixing is employed. be able to. The wet mixing can be performed by, for example, dispersing and mixing the oil-absorbing crosslinked polymer (I) and the organic acid metal salt (II) in water in the presence of a surfactant, if necessary, and then filtering and drying. . The dry mixing can be carried out, for example, by mixing the oil-absorbing crosslinked polymer (I) and the organic acid metal salt (II) with a colloid mill, a kneader or a mixer. In particular, wet mixing is preferable because an aqueous dispersion of the oil-absorbing crosslinked polymer (I) obtained by the suspension polymerization can be mixed with the organic acid metal salt (II) as it is. Further, a method of mixing the crosslinked polymer (I) obtained by bulk polymerization and the organic acid metal salt (II) while adjusting the particle size by a pulverizing operation or the like can also be adopted.

The oil-absorptive cross-linked polymer (I) and the organic acid metal salt (II) in the oil-absorbing agent of the present invention are mixed in an amount of 30 to 99 parts by weight of the oil-absorptive cross-linked polymer (I) and an organic acid metal salt. (II) is a ratio of 1 to 70 parts by weight. If the amount of the organic acid metal salt (II) is less than 1 part by weight, the particles of the oil-absorbing crosslinked polymer (I) aggregate with each other, and the oil absorption rate decreases, which is not preferable. Further, it is not preferable to use a large amount of the organic acid metal salt (II) in an amount exceeding 70 parts by weight, because the oil absorption amount of the oil absorbent and the oil retaining performance are deteriorated.

The oil absorbing agent thus obtained can be used in various forms. For example, the oil absorbent of the present invention may be used as it is by adding or spraying it to an oil / water mixed system such as an oil / water suspension or an aqueous solution in which oil is dissolved, or oil.
It may be used after being filled in an open container such as a cylindrical tube.
Further, the oil absorbing agent of the present invention may be granulated with a binder if necessary, attached to or contained in a fiber, or filled in a cloth bag or a porous package for use.

Further, the oil absorbing agent of the present invention is, for example, chaff, straw, pulp, cotton, porous lime, porous silica,
It can also be used in combination with a conventionally known oil absorbent or filler such as porous pearlite or polypropylene fiber.

[0029]

EXAMPLES Next, the present invention will be described in detail with reference to examples, but the present invention is not limited thereto. In the examples, parts represent parts by weight unless otherwise specified.

[0030]

Example 1 A 500 ml flask equipped with a thermometer, a stirrer, a gas inlet tube, and a reflux condenser was charged with polyoxyethylene alkyl ether (manufactured by Nippon Shokubai Co., Ltd., trade name: Sophthanol 150, which is also used in the following examples. 3 parts (commercially used) were dissolved in 300 parts of water and charged, and the inside of the flask was replaced with nitrogen while stirring and heated to 40 ° C. under a nitrogen stream. Then, 99.794 parts of nonylphenyl acrylate (SP value: 8.3) as the monomer (A), 0.206 parts of 1,6-hexanediol diacrylate as the crosslinkable monomer (B), and a polymerization initiator. Was added to the flask all at once, and the mixture was vigorously stirred under the condition of 750 rpm.

Then, the temperature inside the flask was raised to 80 ° C. and maintained at the same temperature for 2 hours to carry out the polymerization reaction. Then, the temperature inside the flask was further raised to 90 ° C. and maintained for 2 hours to complete the polymerization. By doing so, an aqueous dispersion containing the oil-absorptive cross-linked polymer (1) having an average particle diameter of 30 μm (resin content 25% by weight)
I got

Further, 5 parts of fine powder of water-insoluble calcium stearate (average particle size 8 μm) was added to an aqueous solution in which 1.5 parts of the polyoxyethylene alkyl ether was dissolved in 150 parts of water, and the mixture was added at 300 rpm. The mixture was stirred under the conditions to obtain an aqueous dispersion of calcium stearate. Then, 60 parts of an aqueous dispersion containing the oil-absorptive cross-linked polymer (1) obtained by the previous polymerization was gradually added and stirring was continued for 10 minutes to obtain an aggregate composed of the oil-absorptive cross-linked polymer (1) and calcium stearate. Got The aggregate was filtered off and dried at 80 ° C. to obtain an oil absorbing agent (1) of the present invention consisting of 15 parts of the oil absorbing crosslinked polymer (1) and 5 parts of calcium stearate. The oil absorbing agent (1) was granulated to have an average particle size of 3 mm.

[0033]

Example 2 Hexadecyl methacrylate (SP value: 7.8) 49.93 as the monomer (A) in Example 1.
0 part and N-octyl methacrylamide (SP value:
8.6) 49.930 parts, divinylbenzene O.V. as the crosslinkable monomer (B). By the same method as in Example 1 except that 140 parts were used instead and the number of revolutions was changed to 200 rpm, an aqueous dispersion containing the oil-absorbing crosslinked polymer (2) having an average particle diameter of 300 μm (resin content 25 wt. %) Was obtained.

Further, 5 parts of the same fine powder of calcium stearate as used in Example 1 was added to an aqueous solution prepared by dissolving 1.5 parts of the polyoxyethylene alkyl ether in 150 parts of water and stirred under the condition of 300 rpm. An aqueous dispersion of calcium stearate was obtained. Then, 180 parts of an aqueous dispersion containing the oil-absorbing crosslinked polymer (2) was gradually added and stirring was continued for 10 minutes to obtain an aggregate containing the oil-absorbent crosslinked polymer (2) and calcium stearate. The aggregate was filtered off and dried at 80 ° C. to obtain an oil absorbent (2) of the present invention consisting of 45 parts of the oil-absorbing crosslinked polymer (2) and 5 parts of calcium stearate. This oil absorbent (2) is
It was granulated to have an average particle size of 5 mm.

[0035]

Example 3 Dodecyl acrylate (SP value: 7.9) 57.7 as a monomer (A) in an aqueous solution prepared by dissolving 3 parts of the polyoxyethylene alkyl ether in 300 parts of water.
72 parts and N, N-dioctyl acrylamide (SP
Value: 8.2) 38.515 parts, polypropylene glycol dimethacrylate (molecular weight 4000) as the crosslinkable monomer (B) 3.713 parts, and as the polymerization initiator 2,2
′ -Azobisisobutyronitrile O. A solution consisting of 5 parts was added and mixed with a homomixer at 10,000 rpm for 10 minutes to obtain an aqueous dispersion of a monomer.

Then, an aqueous dispersion of the above monomer was charged into a 500 ml flask equipped with a thermometer, a stirrer, a gas introduction tube and a reflux condenser, and the inside of the flask was replaced with nitrogen while vigorously stirring under the conditions of 400 rpm. did. Subsequently, the temperature inside the flask was raised to 70 ° C. under a nitrogen stream, the polymerization temperature was maintained for 2 hours to carry out the polymerization reaction, and then the temperature was further raised to 90 ° C. to complete the polymerization, and the oil absorption with an average particle diameter of 5 μm was obtained. An aqueous dispersion (resin pure content: 25% by weight) containing the crosslinkable polymer (3) was obtained.

Fine powder of zinc caprylate (average particle size 6) which is substantially insoluble in water in an aqueous solution prepared by dissolving 1.5 parts of the polyoxyethylene alkyl ether in 150 parts of water.
μm) 5 parts and stirred under the condition of 300 rpm to obtain an aqueous dispersion of zinc caprylate. Then, 30 parts of an aqueous dispersion containing the oil-absorbent crosslinked polymer (3) was gradually added and stirring was continued for 10 minutes to obtain an aggregate composed of the oil-absorbent crosslinked polymer (3) and zinc caprylate. Further, this aggregate is filtered off and
An oil-absorbing crosslinked polymer (3) is obtained by drying at 0 ° C.
An oil absorbent (3) of the present invention consisting of 7.5 parts and 5 parts of zinc caprylate was obtained. This oil absorbing agent (3) has an average particle diameter of 3 m.
It was granulated to a size of m.

[0038]

Example 4 99.823 parts of dodecyl acrylate (SP value: 7.9) as the monomer (A) in Example 1,
As the crosslinkable monomer (B), ethylene glycol diacrylate O. By the same method as in Example 1 except that 177 parts was used instead, an aqueous dispersion containing the oil-absorbing crosslinked polymer (4) having an average particle diameter of 30 μm (resin pure content: 25% by weight) was obtained.

Further, to an aqueous solution prepared by dissolving 1.5 parts of the polyoxyethylene alkyl ether in 150 parts of water was added 5 parts of fine powder of water-insoluble aluminum stearate (average particle size: 5 μm), and 300 rpm. The mixture was stirred under the conditions described above to obtain an aqueous dispersion of aluminum stearate.
Then, 60 parts of an aqueous dispersion containing the oil-absorbent crosslinked polymer (4) was gradually added and stirring was continued for 10 minutes to obtain an aggregate composed of the oil-absorbent crosslinked polymer (4) and aluminum stearate. Further, the agglomerate was filtered off and dried at 80 ° C. to obtain an oil absorbent (4) of the present invention consisting of 15 parts of the oil-absorbent crosslinked polymer (4) and 5 parts of aluminum stearate. The oil absorbing agent (4) was granulated to have an average particle size of 3 mm.

[0040]

Example 5 In Example 1, t- was used as the monomer (A).
Butylstyrene (SP value: 7.9) 54.881 parts and 1-decene (SP value: 7.0) 44.903 parts, divinylbenzene O.C. By the same method as in Example 1 except that 216 parts was used instead, an aqueous dispersion (resin content 25% by weight) containing the oil-absorbent crosslinked polymer (5) was obtained. Then, the oil-absorbing crosslinked polymer (5) was filtered from the aqueous dispersion, dried and pulverized with a colloid mill to obtain particles of the oil-absorbent crosslinked polymer (5) having an average particle diameter of 5 μm.

Furthermore, 75 parts of the granular material (average particle size: 5 μm) of the oil-absorbing crosslinked polymer (5) and 25 parts of the same fine aluminum stearate powder as used in Example 4 were mixed using a colloid mill. By doing so, the oil absorbing agent (5) of the present invention was obtained.

[0042]

Example 6 Nonylphenyl acrylate (SP value: 8.3) 74.79 as the monomer (A) in Example 1.
3 parts and hydroxyethyl acrylate (SP value: 1
0.3) The same method as in Example 1 except that 24.931 parts was used instead and the amount of 1,6-hexanediol diacrylate as the crosslinkable monomer (B) was changed to 0.276 parts. Thus, an aqueous dispersion (resin content of 25% by weight) containing the oil-absorbent crosslinked polymer (6) having an average particle diameter of 30 μm was obtained.

Further, 5 parts of barium behenate fine powder (average particle size: 8 μm), which is substantially insoluble in water, was added to an aqueous solution prepared by dissolving 1.5 parts of the polyoxyethylene alkyl ether in 150 parts of water, and added at 300 rpm. The mixture was stirred under the conditions described above to obtain an aqueous dispersion of barium behenate. Then, 60 parts of an aqueous dispersion containing the oil-absorbing crosslinked polymer (6) was gradually added and stirring was continued for 10 minutes to obtain an aggregate consisting of the oil-absorbing crosslinked polymer (6) and barium behenate. Further, the agglomerate was filtered off and dried at 80 ° C. to obtain an oil absorbing agent (6) of the present invention consisting of 15 parts of the oil-absorbing crosslinked polymer (6) and 5 parts of barium behenate. The oil absorbing agent (6) was granulated to have an average particle size of 3 mm.

[0044]

Example 7 In Example 1, 99.811 parts of vinyl laurate (SP value: 7.9) as the monomer (A) and trimethylolpropane triacrylate O.V. as the crosslinkable monomer (B). Example 1 except that 187 parts were used instead.
By a method similar to the above, an aqueous dispersion (resin content 25% by weight) containing the oil-absorbent crosslinked polymer (7) having an average particle diameter of 30 μm was obtained.

Further, 5 parts of the same fine aluminum stearate powder as used in Example 4 was added to an aqueous solution prepared by dissolving 1.5 parts of the polyoxyethylene alkyl ether in 150 parts of water, and the mixture was added under the conditions of 300 rpm. By stirring, an aqueous dispersion of aluminum stearate was obtained. Then, 60 parts of an aqueous dispersion containing the oil-absorptive cross-linked polymer (7) was gradually added,
Stirring was continued for a minute to obtain an aggregate composed of the oil-absorbent crosslinked polymer (7) and aluminum stearate. Further, the aggregate was filtered off and dried at 80 ° C. to obtain an oil absorbent (7) of the present invention consisting of 15 parts of the oil-absorbing crosslinked polymer (7) and 5 parts of aluminum stearate. The oil absorbing agent (7) was granulated to have an average particle size of 3 mm.

[0046]

Comparative Example 1 An average particle diameter of 30 μm was obtained in the same manner as in Example 4 except that the amount of dodecyl acrylate was changed to 94.637 parts and the amount of ethylene glycol diacrylate was changed to 5.363 parts. An aqueous dispersion containing the comparative polymer (1) was obtained. Using this aqueous dispersion and aluminum stearate, a comparative oil absorbent (1) consisting of 15 parts of the comparative polymer (1) and 5 parts of aluminum stearate was obtained in the same manner as in Example 4. This comparative oil absorbent (1) was granulated to have an average particle size of 3 mm.

[0047]

Comparative Example 2 Dodecyl acrylate 9 in Example 4
Instead of the monomer (A) consisting of 9.823 parts, 39.854 parts of dodecyl acrylate and methacrylic acid (SP
Value: 10.1) 59.780 parts were used, and Comparative Polymer (2) having an average particle size of 30 μm was prepared in the same manner as in Example 4 except that the amount of ethylene glycol diacrylate was changed to 0.366 parts. An aqueous dispersion containing it was obtained. Using this aqueous dispersion and aluminum stearate, a comparative oil absorbent (2) consisting of 15 parts of the comparative polymer (2) and 5 parts of aluminum stearate was obtained in the same manner as in Example 4. This comparative oil absorbent (2) was granulated to have an average particle size of 3 mm.

[0048]

Comparative Example 3 An aqueous dispersion containing the comparative polymer (3) having an average particle size of 30 μm was obtained by the same method as in Example 4 except that the crosslinkable monomer (B) was not used. It was
Using this aqueous dispersion and aluminum stearate, a comparative oil absorbent (3) consisting of 15 parts of comparative polymer (3) and 5 parts of aluminum stearate was prepared in the same manner as in Example 4.
I got This comparative oil absorbent (3) was granulated to have an average particle size of 3 mm.

[0049]

Comparative Example 4 1 part of the same fine powder of aluminum stearate as used in Example 4 was added to an aqueous solution prepared by dissolving 1.5 parts of the polyoxyethylene alkyl ether in 150 parts of water, and the mixture was added under the condition of 300 rpm. By stirring, an aqueous dispersion of aluminum stearate was obtained. Then, an aqueous dispersion 40 containing the oil-absorptive crosslinked polymer (4) obtained by the polymerization in Example 4 was obtained.
0 part was gradually added and stirring was continued for 10 minutes to obtain an aggregate consisting of the oil-absorbing crosslinked polymer (4) and aluminum stearate. Further, this agglomerate is filtered off, pulverized with a colloid mill and dried at 80 ° C. to obtain 100 parts of the oil-absorbing crosslinked polymer (4) and 1 part of aluminum stearate.
To obtain a comparative oil absorbent (4). This comparative oil absorbent (4) was granulated to have an average particle size of 7 mm.

[0050]

Comparative Example 5 5 parts of the same fine powder of aluminum stearate as used in Example 4 was added to an aqueous solution prepared by dissolving 1.5 parts of the polyoxyethylene alkyl ether in 150 parts of water, and added under the condition of 300 rpm. By stirring, an aqueous dispersion of aluminum stearate was obtained. Then, 8 parts of an aqueous dispersion containing the oil-absorbing crosslinked polymer (4) obtained in Example 4 was gradually added and stirring was continued for 10 minutes to agglomerate the oil-absorbing crosslinked polymer (4) and aluminum stearate. I got a thing. Further, this agglomerate was filtered off and dried at 80 ° C. to obtain a comparative oil absorbent (5) consisting of 2 parts of the oil-absorbing crosslinked polymer (4) and 5 parts of aluminum stearate. This comparative oil absorbent (5) was granulated to have an average particle size of 3 mm.

[0051]

[Example 8] Oil absorbing agent (1) obtained in Examples 1-7
(7) and the comparative oil absorbing agent (1) obtained in Comparative Examples 1 to 5
5 g of each of (5) to (5) were immersed in kerosene for 24 hours under the condition of 20 ° C., and then collected by filtration on a 508 mesh nylon filter cloth. Next, the kerosene that was not absorbed and retained by the oil absorbing agent was wiped off, the weight of the oil absorbing agent was measured, and the saturated absorption amount of kerosene was calculated according to the following formula. The results are shown in Table 1.

Saturated absorption amount (g) = weight of oil absorbent after immersion in kerosene-weight of oil absorbent before immersion in kerosene

[0053]

[Example 9] Oil absorbing agent (1) obtained in Examples 1 to 7
(7) and the comparative oil absorbing agent (1) obtained in Comparative Examples 1 to 5
5 g of each of (5) to (5) were weighed into a cylindrical glass test tube having an inner diameter of 20 mm. Then, under the condition of 20 ° C., the kerosene equivalent to half the saturated absorption amount of kerosene obtained in Example 8 was charged into each test tube at a time, and the time until no fluidized kerosene was observed (oil absorption time) Was measured. The results are shown in Table 1.

[0054]

[Table 1]

[0055]

The oil-absorbing agent of the present invention comprises a specific oil-absorbing crosslinked polymer and an organic acid metal salt. Due to their synergistic effect, only the oil can be selectively absorbed even from the oil-water mixed system and once absorbed. The oil retainability is excellent and the oil absorption rate is extremely fast. Furthermore, since the oil absorbing agent of the present invention is unlikely to aggregate with each other during oil absorption even when processed into fine particles, the oil absorbing ability originally possessed as an oil absorbing agent can be efficiently and quickly exhibited.

Therefore, the oil absorbing agent of the present invention is used for the recovery of oil spilled at sea, the recovery of floating oil, the recovery of oil in waste water, the emulsion breaker, the oil spill treatment agent, the edible waste oil treatment agent, the machine waste oil treatment agent, and the household or industrial oil. It can be applied to a very wide range of applications such as oil wipes, chemical wipes, oil leak sensors, oil sealants, and various oil retention agents, and it is also used as a release base material for various fragrances, insecticides, fish collecting agents, etc. can do.

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Claims (3)

(57) [Claims] 1. A monomer (A) having one polymerizable unsaturated group in a molecule containing a monomer having a solubility parameter (SP value) of 9 or less as a main component in an amount of 96 to 99.999% by weight, and 0.001 to 4% by weight of a crosslinkable monomer (B) having at least two polymerizable unsaturated groups in the molecule (however, the total amount of the monomers (A) and (B) is 100% by weight). From 30 to 99 parts by weight of an oil-absorptive cross-linked polymer (I) obtained by polymerizing a monomer component consisting of and an organic acid metal salt (II) having a solubility of 1 g or less in 100 g of water at 20 ° C. Oil absorbent. 2. The monomer (A) has at least one aliphatic hydrocarbon group having 3 to 30 carbon atoms and is alkyl (meth) acrylate, alkylaryl (meth) acrylate, alkyl (meth) acrylamide. , Alkylaryl (meth) acrylamide, fatty acid vinyl ester,
The oil absorbent according to claim 1, which contains at least one unsaturated compound (a) selected from the group consisting of alkylstyrene and α-olefin as a main component. 3. The oil-absorbing crosslinked polymer (I) has an average particle size of 0.
The oil absorbent according to claim 1, which is a granular material having a particle size of 5 to 500 µm, and the organic acid metal salt (II) is a powder having an average particle diameter of 0.01 to 300 µm.