JP3125023B2 - Hydrophilic solid particles having a hydrophilic group on the surface, method for producing the same, and flocculant - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel hydrophilic solid particle having a hydrophilic group on the surface, a method for producing the same, and a novel flocculant.

[0002]

2. Description of the Related Art Conventionally, a polymer coagulant, an inorganic salt coagulant, a surfactant and the like have been used for agglomeration of particles in a suspension. However, since these existing flocculants dissolve in the suspension, the flocculants flow out into the wastewater, which may make wastewater treatment difficult or pollute the environment. Therefore, a flocculant without such a problem is desired. On the other hand, in the fields of cosmetics and foods, products based on an emulsion obtained by emulsifying oily solid particles in water have been made.In this case, the solid particles themselves do not have a hydrophilic group. Therefore, there is a problem in terms of the emulsion stability of the solid particles.

[0003]

SUMMARY OF THE INVENTION The present invention provides a novel flocculant which does not cause the above-mentioned problems such as wastewater treatment difficulties and environmental pollution, and a method for producing the same. It is an object of the present invention to provide a solid particle having a hydrophilic group on the surface, on which an oil droplet type emulsion can be easily formed, and a method for producing the same.

[0004]

Means for Solving the Problems The inventors of the present invention have repeatedly studied to solve the above-mentioned problems, and as a result, have completed the present invention. That is, according to the present invention, the water-soluble solid particles and the surfactant having a hydrophilic group and a hydrophobic group are composed of the heat-fusible water-insoluble solid particles, and the surfactant is bonded to the solid particles through the hydrophobic group. And the amount of the surfactant bound is the water-insoluble
The present invention provides hydrophilic solid particles having a hydrophilic group on a surface, which is 0.01 to 0.6% by weight of the solid particles. Further, according to the present invention, a step of forming an oil-in-water emulsion by granulating a melt of a water-insoluble substance in water in the presence of a surfactant, and cooling the emulsion to form the water-insoluble substance a step of solid particles of the melt particles, the method for producing a hydrophilic solid particles having a hydrophilic group, characterized by comprising the step of separating the solid particles from the water is provided. Furthermore, according to the present invention, a step of forming an oil-in-water emulsion by dropping a melt of a water-insoluble substance in which a surfactant is dissolved in water, and cooling the emulsion to form the water-insoluble A method for producing the hydrophilic solid particles having a hydrophilic group is provided, which comprises a step of converting the melt particles of the substance into solid particles, and a step of separating the solid particles from water. Furthermore, according to the present invention,
It is composed of heat-meltable non-water-soluble solid particles and an anionic surfactant having an anionic hydrophilic group and a hydrophobic group, and the surfactant is bonded to the solid particles through the hydrophobic group .
The binding amount of the surfactant is 0.1% of the water-insoluble solid particles.
The present invention provides a flocculant for suspended particles, comprising hydrophilic solid particles having an anionic hydrophilic group on the surface in an amount of from 0.01 to 0.6% by weight . And also according to the invention,
It comprises a heat-meltable water-insoluble solid particle and a cationic surfactant having a cationic hydrophilic group and a hydrophobic group, and the surfactant is bonded to the solid particle through the hydrophobic group .
The binding amount of the surfactant is 0.1% of the water-insoluble solid particles.
There is provided a flocculant for suspended particles, comprising hydrophilic solid particles having a cationic hydrophilic group on the surface in an amount of from 0.01 to 0.6% by weight .

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a surfactant bonded to the surface of heat-meltable, water-insoluble solid particles (hereinafter, also simply referred to as a substrate) has a surfactant having a hydrophilic group and a hydrophobic group. Agent. Such surfactants include anionic surfactants having anionic hydrophilic groups, cationic surfactants having a cationic hydrophilic group, nonionic surfactants having a nonionic hydrophilic group, and anionic surfactants having a nonionic hydrophilic group. Amphoteric surfactants having an ionic hydrophilic group and a cationic hydrophilic group are included. Also,
Examples of the hydrophilic group contained in these surfactants include, as the anionic hydrophilic group, a carboxyl group, a sulfonic acid group, a xanthogenic acid group, a phosphoric acid group, a sulfate group, and the like. Or, an unsubstituted quaternary ammonium group or the like is exemplified, and as the nonionic hydrophilic group, a polyoxyethylene group or an alcoholic hydroxyl group is exemplified. On the other hand, examples of the hydrophobic group possessed by the surfactant include a hydrocarbon group having 5 or more prime numbers and a halogenated hydrocarbon group, and these hydrophobic groups include an aliphatic group, a cycloaliphatic group, and an aromatic group. Is done.

Specific examples of the surfactant bound to the surface of the hydrophilic solid particles of the present invention are as follows. Anionic surfactants: alkali salts of higher fatty acids, alkali salts of alkyl sulfates, alkali salts of olefin sulfates, alkali salts of alkyl benzene sulfonic acids, alkali salts of alkyl naphthalene sulfonic acids, alkali salts of dialkyl sulfosuccinic acids, alkali salts of alkyl xanthogenic acids, and others. Cationic surfactants: trimethylaminoethylalkylamide halides, alkylpyridinium sulfates, alkyltrimethylammonium halides, and others. Nonionic surfactants: polyoxyethylene alkyl ether, polyoxyethylene fatty acid ester, polyoxyethylene alkyl phenol ether, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, sucrose fatty acid ester, alkyl glucoside, and others. Amphoteric surfactants: alkyl betaines, alkyl diethylene triamino acetic acids, and others.

The base material used in the present invention is a water-insoluble substance which is a solid at room temperature and has a melting point of 30 ° C. or more, preferably 50 ° C.
° C or higher. The upper limit of the melting point is not limited, but is usually 2
The temperature is not higher than 00 ° C, preferably not higher than 150 ° C, and a substrate having a melting point of 50 to 90 ° C is preferable from the viewpoint of production. Further, the base material may be a single product or a mixed product, or may be a synthetic product or a natural product. Examples of the substance serving as a base material in the present invention include synthetic compounds such as hydrocarbons, higher alcohols, higher fatty acids, higher esters, higher acid amides, and olefin polymers; vegetable waxes such as wood wax and candelilla wax; And animal waxes such as paraffin wax and ceresin; animal and plant fats such as dehydrated lanolin and hydrogenated castor oil; and natural products such as derivatives thereof.

The hydrophilic solid particles of the present invention are particles having a hydrophilic group of a surfactant on the surface of base particles. The amount of the surfactant in the particles is 0.01 to 0.6%, preferably 0.03 to 0.15% of the weight of the base material. The particle size is 1 μm to 1 mm, preferably 10 μm.
m to 0.1 mm. Since the hydrophilic solid particles of the present invention have hydrophilic groups on the surface, they easily become oil-in-water emulsions when water is added, and are useful as oil bases for producing creamy and emulsion liquid medicines, cosmetics, and foods. It is. Further, a functional material can be obtained by giving a special function to the hydrophilic group on the surface. For example, if a hydrophilic group is given a charge or has a chemisorption ability, it can be used as a flocculant for suspended particles as described below. When hydrophilic solid particles having an anionic hydrophilic group on the surface are added to the suspension, the positively charged suspended particles aggregate due to electrostatic force between the particles and the anionic hydrophilic group. Therefore, the hydrophilic solid particles of the present invention having an anionic hydrophilic group on the surface can be used as an aggregating agent for positively charged suspended particles.

When hydrophilic solid particles having a cationic hydrophilic group on the surface are added to a suspension, the negatively charged suspended particles are aggregated by electrostatic force between the suspension and the cationic hydrophilic group. Therefore, the hydrophilic solid particles of the present invention having a cationic hydrophilic group on the surface can be used as an aggregating agent for negatively charged suspended particles. When hydrophilic solid particles having a xanthate group on the surface are added to a suspension, the xanthate group is chemically adsorbed on the surface of a non-ferrous metal such as copper, zinc and lead or a sulfide thereof. And a flocculant for suspended particles. When hydrophilic solid particles having a carboxyl group on the surface are added to the suspension, the carboxyl groups are chemically adsorbed on the surface of the metallic iron or iron oxide, so that the suspended particles of metallic iron or iron oxide aggregate. Therefore, the hydrophilic solid particles of the present invention having a carboxyl group on the surface can be used as a flocculant for suspended particles composed of metallic iron or iron oxide.

As mentioned above, the hydrophilic solid particles of the present invention can be used as a flocculant for suspended particles. Since this flocculant is in particulate form, solid-liquid separation is easy, and since it is insoluble in water, the suspended particles do not dissolve in the wastewater after flocculation. It does not cause problems such as processing difficulties and environmental pollution. Further, when the aggregate aggregated with the flocculant is heated to a temperature higher than the melting point of the flocculant, the flocculant can be separated and recovered. Since the hydrophilic solid particles of the present invention are easily emulsified and dispersed in water as described above, they are useful as an oily base for producing creamy or milky medicines, cosmetics, and foods. As the surfactant used here, a nonionic surfactant with low skin irritation and high safety is preferable.

The hydrophilic solid particles of the present invention are obtained by granulating a melt of a water-insoluble substance in water in the presence of a surfactant to form an oil-in-water emulsion, and cooling the emulsion to form the oil-in-water emulsion. It can be produced by sequentially performing a step of solidifying melt particles of a water-soluble substance into solid particles and a step of separating the solid particles from water (Method I). Further, a step of forming a droplet of the melt of the water-insoluble substance in which the surfactant is dissolved in water to form an oil-in-water emulsion, and cooling the emulsion to form particles of the melt of the water-insoluble substance. It can be produced by sequentially performing a step of forming solid particles and a step of separating the solid particles from water (Method II). I
When the hydrophilic solid particles of the present invention are produced by the method, the amount of water used is 5 to 100 times by weight, preferably 10 to 20 times by weight of the amount of water-insoluble substance (substrate) used. The use amount of the agent is desirably 0.1 to 5% by weight, preferably 0.5 to 2% by weight of the base material use amount. Further, the emulsion formation temperature is preferably 5 to 30 ° C., preferably 10 to 15 ° C. higher than the melting point of the substrate, and the emulsion cooling temperature is 10 to 50 ° C., preferably 25 to 50 ° C. above the melting point of the substrate.
It is desirable to keep the temperature at 40 ° C. low.

When the hydrophilic solid particles of the present invention are produced by the method II, the amount of water used is preferably 5 to 100 times by weight, preferably 10 to 20 times by weight the amount of the substrate, The amount is desirably 0.1 to 2% by weight, preferably 0.5 to 1% by weight of the amount of the base material used. The emulsion formation temperature is 5 to 30 ° C., preferably 1 to 30 ° C. from the melting point of the substrate.
The temperature is preferably 0 to 15 ° C. higher, and the emulsion cooling temperature is 10 to 50 ° C., preferably 25 to 4 ° C. above the melting point of the base material.
It is desirable to keep the temperature at 0 ° C. When the hydrophilic solid particles of the present invention are produced by the methods I and II, the emulsion can be formed by a conventional method such as stirring or ultrasonic treatment. Further, the generated solid particles can be separated from the mother liquor by a conventional method such as filtration or centrifugation. The particle size of the hydrophilic solid particles can be adjusted by the emulsion forming conditions such as the stirring speed, the mixing ratio between the base material and the surfactant, and the like.

[0013]

Next, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples.

Example 1 200 ml of purified water was added to 20 g of paraffin having a melting point of 60 to 62 ° C., and this was heated to 70 ° C. in a water bath to make the paraffin liquid. After 0.1 g of potassium amyl xanthogenate was added to this liquid, the mixture kept at 70 ° C. was stirred with a homogenizer for 1 minute to form an oil-in-water emulsion. The mother liquor was filtered off. This solid has an average particle size of about 10μ.
m of particulate matter, and 0.0008 g of potassium amyl xanthate was contained in 1 g of the dried solid. 500 ml of a suspension having a solid concentration of 0.1% by weight containing a galena particle having an average particle diameter of 7 μm and quartz particles having an average particle diameter of 8 μm as solid components and water as a liquid component was prepared. The mixing ratio of the quartz particles and the galena particles in the suspension is 1: 1 by weight. To the suspension was added 1 g of the above-mentioned particulate solid, and the mixture was gently stirred for 10 minutes, and then the aggregate and the mother liquor were separated by a gradient method.
The weight ratio of the galena particles to the quartz particles in the separated aggregate was 0.92: 0.08, and the galena particles were selectively aggregated.

Example 2 200 ml of purified water was added to 20 g of paraffin having a melting point of 60 to 62 ° C., and this was heated to 70 ° C. in a water bath to make the paraffin liquid. To this solution was added 0.1 g of dodecyl ammonium hydrochloride, and the mixture was homogenized with a homogenizer.
The mixture was stirred for 1 minute to form an oil-in-water emulsion, and after the emulsion was cooled to room temperature, the solid and the mother liquor were separated by filtration. This solid was a particulate matter having an average particle size of about 7 μm, and contained 0.1 g of dodecyl ammonium hydrochloride in 1 g of the dried solid.
001 g. 500 ml of a 300 ppm quartz suspension was prepared. 0.1 g of the above-mentioned particulate solid is added to this suspension, and gently stirred for 10 minutes.
After standing for 0 minutes, the quartz particles aggregated and the turbidity of the supernatant of the suspension became 5. The turbidity of the suspension before the aggregation of the quartz particles was 78.

Comparative Example 1 500 ml of the same quartz suspension as used in Example 2
The suspension having a turbidity of 78 was gently stirred for 10 minutes, and allowed to stand for 10 minutes. However, the quartz particles did not aggregate. It was 78, almost the same as before.

Example 3 200 ml of purified water was added to 10 g of paraffin having a melting point of 60 to 62 ° C., and this was heated to 70 ° C. in a water bath to make the paraffin liquid. After 0.1 g of polyoxyethylene sorbitan laurate was added to this solution, the mixture was stirred with a homogenizer for 1 minute to form an oil-in-water emulsion. After cooling the emulsion to room temperature, the solid and mother liquor were filtered. Different. This solid was a particulate matter having an average particle diameter of about 10 μm, and 1 g of the dried solid contained 0.0015 g of polyoxyethylene sorbitan laurate.
When 200 ml of purified water was added to 10 g of the solid and stirred, an oil-in-water emulsion was easily formed.

Example 4 200 ml of purified water was added to 20 g of paraffin having a melting point of 60 to 62 ° C., and this was heated to 70 ° C. in a water bath to make the paraffin liquid. After 0.1 g of lauryl diethylene triaminoacetic acid was added to this solution, the mixture was stirred with a homogenizer for 1 minute to form an oil-in-water emulsion, and after cooling the emulsion to room temperature, a solid substance and a mother liquor were separated by filtration. . This solid was a particulate matter having an average particle size of about 10 μm, and 1 g of the dried solid contained 0.001 g of lauryldiethylenetriaminoacetic acid. When 200 ml of purified water was added to 20 g of the solid and stirred, an oil-in-water emulsion was easily formed.

Example 5 0.12 g of sodium stearyl sulfate was added to a mixture of 5 g of paraffin having a melting point of 60 to 62 ° C. and 5 g of stearyl alcohol, and the mixture was heated to 70 ° C. in a water bath to obtain a uniform liquid. This solution was heated to 70 ° C. and purified water 250
Then, the mixture was stirred with a homogenizer for 1 minute to form an oil-in-water emulsion. After cooling the emulsion to room temperature, a solid substance and a mother liquor were separated by filtration. This solid was a particulate matter having an average particle size of about 10 μm, and 0.003 g of sodium stearyl sulfate was contained in 1 g of the dried solid. When 200 ml of purified water was added to 10 g of the solid and stirred, an oil-in-water emulsion was easily formed.

[0020]

According to the present invention, when the hydrophilic solid particles of the present invention are used as a flocculant for suspended particles, unlike the conventional flocculant, the flocculant does not remain in the waste liquid after the flocculation and separation, and therefore, the waste liquid Problems such as difficulties in waste liquid treatment and environmental pollution caused by dissolution of the coagulant do not occur. When the hydrophilic solid particles of the present invention are used as an oil base for medicines or cosmetics, a creamy or milky product can be easily produced simply by adding purified water to the solid particles.

Continued on the front page (72) Inventor Rei Arai 16-3 Onogawa Tsukuba, Ibaraki Pref., National Institute of Advanced Industrial Science and Technology (72) Inventor Hiroshi Sakamoto 16-3 Onogawa Tsukuba, Ibaraki Pref. In the laboratory

Claims (5)

(57) [Claims] 1. A consists of a surfactant having a hot-melt water-insoluble solid particles and the hydrophilic and hydrophobic groups are bound with the solid particles said surfactant through said hydrophobic water group, and The
The amount of the surfactant bound is 0.01% of the water-insoluble solid particles.
A hydrophilic solid particle having a hydrophilic group on the surface, characterized in that the content of the hydrophilic solid particle is 0.6 to 0.6% by weight 2. A step of granulating a melt of a water-insoluble substance in water in the presence of a surfactant to form an oil-in-water emulsion, and cooling the emulsion to form particles of the melt of the water-insoluble substance. 2. The step of converting the solid particles into solid particles, and the step of separating the solid particles from water.
3. The method for producing hydrophilic solid particles having a hydrophilic group described in 1. above. 3. A step of forming a droplet of a water-insoluble substance in which a surfactant is dissolved in water to form an oil-in-water emulsion, and cooling the emulsion to melt the water-insoluble substance. 2. The method for producing hydrophilic solid particles having a hydrophilic group according to claim 1, comprising a step of converting the liquid particles into solid particles and a step of separating the solid particles from water. 4. A method comprising: heat-fusible, water-insoluble solid particles; and an anionic surfactant having an anionic hydrophilic group and a hydrophobic group, wherein the surfactant binds to the solid particles via the hydrophobic group. And the amount of the surfactant bound is the water-insoluble
An aggregating agent for suspended particles, comprising hydrophilic solid particles having an anionic hydrophilic group on the surface which accounts for 0.01 to 0.6% by weight of the solid particles. 5. A method comprising: heat-fusible, water-insoluble solid particles; and a cationic surfactant having a cationic hydrophilic group and a hydrophobic group, wherein the surfactant is bonded to the solid particles via the hydrophobic group. And the amount of the surfactant bound is the water-insoluble
A flocculant for suspended particles, comprising hydrophilic solid particles having a cationic hydrophilic group on the surface, which is 0.01 to 0.6% by weight of the solid particles.