JPS5920365B2 - Emulsion type flocculant with good fluidity - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polymer emulsion type wastewater flocculant having good fluidity.

Water-soluble or hydrophilic polymers used as flocculants are usually provided industrially in the form of powders; pastes or water-in-oil emulsions. Among these, water-in-oil emulsion-like products have been attracting attention in recent years because they have advantages over the former two, such as rapid dispersion and dissolution in water, and ease of continuous dissolution equipment. ing. 35 However, these known water-in-oil emulsion products
In order to uniformly disperse and dissolve the product in water, a phase inversion accelerator (so-called activator) is required, the emulsion has poor fluidity and is difficult to transport within a capillary, or the product has poor stability over time. It has drawbacks such as:

In this respect, the monomer represented by general formula (1) or a mixture thereof with other vinyl monomers (
The same was true for water-in-oil polymer emulsions produced by emulsion polymerization of monomers (referred to as monomers in the present invention) by conventionally known techniques.

For example, Japanese Patent Publication No. 34-10644 describes a manufacturing method using a conventional water-in-oil emulsifier with a low HLB value as a surfactant, but the emulsion obtained by this method has a high apparent viscosity; It has poor liquidity and poor stability over time. Further, when uniformly dispersing and dissolving this in water, a phase inversion accelerator such as a surfactant is required. Furthermore, JP-A-50-72982 describes a method for producing a polymer emulsion using 20% by weight or more of an oil phase of a surfactant having an HLB value of 7 or more. Water-in-oil polymer emulsions also have high apparent viscosity and poor emulsion fluidity.

Therefore, there are drawbacks such as the need for powerful stirring equipment during production and the difficulty in transporting the product within a thin tube. The present inventors have conducted extensive research on emulsion-type flocculants that overcome these drawbacks, and have finally arrived at the present invention.

That is, the present invention is based on the general formula (1) (wherein R1 is H or CH3; R2 and R3 are each independently an alkyl group having 1 to 4 carbon atoms, or a hydroxyalkyl group having 2 to 4 carbon atoms; R4 is H1 Alkyl group having 1 to 4 carbon atoms, 2 to 4 carbon atoms
4 hydroxyalkyl group or benzyl group: A is an oxygen atom or NH; B is an alkylene group having 1 to 4 carbon atoms or a hydroxyalkylene group having 2 to 4 carbon atoms; X- is an anionic counter ion. 30 to 70% by weight of an aqueous solution of monomers represented by () or a mixture of these and other vinyl monomers, and 70 to 30% by weight of a hydrophobic organic solvent.
are emulsified and dispersed in the presence of a nonionic surfactant having an HLB value of 7 or more in an amount of 5% by weight or more and less than 20% by weight based on the hydrophobic organic solvent to obtain a 1% by weight aqueous solution of the polymer. It is an emulsion-type flocculant with good fluidity, which is obtained by polymerizing so that the viscosity is at least 100 cps.

In general formula (1), R2 and R3 are each independently an alkyl group having 1 to 4 carbon atoms or a hydroxyalkyl group having 2 to 4 carbon atoms.

Examples of the alkyl group having 1 to 4 carbon atoms include methyl group, ethyl group, n- or IsO-propyl group, and butyl group. Examples of the hydroxyalkyl group having 2 to 4 carbon atoms include -CH2CH2OH, -CH2
CH2CH2OH, -CH2CH(CH2OH)CH3
can be given. R4 is H1 an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 2 to 4 carbon atoms, or a benzyl group, and the alkyl group and hydroxyalkyl group are the same as those explained in the section of R2 and R3. . B is an alkylene group having 1 to 4 carbon atoms or 2 to 4 carbon atoms
is a hydroxyalkylene group. Examples of the alkylene group include -CH2CH2-, -CH2CH2CH2
-, -CH2CHCH2-, and the hydroxyalkylene group is, for example, -CH2CH(0H)CH
2- is given. X- is an anionic counterion.
For example, halogen ions such as Cl-, Br-, CH3
OSO3, C, H5OSO3-, HSO4-, H2PO
4-, CH3CO2' ,,CH3C6H4SO3-
, CH3SO3-, NO3-. Preferably halogen ions, CH3OSO3-, C2H5OSO3
-, HSO4'. Examples of the monomer represented by the general formula () include the following monomers (1-A) to (4-A). (1-A) Quaternary nitrogen-containing (meth)acrylate [(meth)acrylate refers to acrylate and methacrylate. The same applies hereafter] ([) (meth) Acryloyloxyalkyl trialkylammonium salts such as 2-(meth)acryloyloxyethyltrimethylammonium chloride, 2-(meth)acryloyloxyethyltrimethylammonium methosulfate, 2-(
meth)acryloyloxyethyltriethylammonium ethosulfate, 3-(meth)acryloyloxypropyldimethylethylammonium methosulfate, etc., kyltrialkylammonium salts such as 3-methacryloyloxy-12-hydroxypyrropyltrimethylammonium chloride, 3 -methacryloyloxy-2-hydroxypropylmethyldiethylammonium chloride, 3
-methacryloyloxy-2-hydroxypropyltrimethylammonium methosulfate, etc. (2-A) 3rd
Salts of nitrogen-containing (meth)acrylates and acids (1) Salts of dialkylaminoalkyl (meth)acrylates, such as 2-dimethylaminoethyl (meth)acrylate sulfate, 2-diethylaminoethyl (meth)acrylate hydrochloride, etc. (Ii ) Salts of dialkylaminohydroxyalkyl (meth)acrylates, such as 3-dimethylamino-2-hydroxypropyl (meth)arylate hydrochloride, 3-diethylamino-2-hydroxypropyl (meth)acrylate sulfate, etc. (3-A) Quaternary nitrogen-containing (meth)acrylamide (1) (meth)acrylamidoalkyltrialkylammonium salts such as 3-acrylamidopropyltrimethylammonium chloride, 2-(meth)aryloylaminoethyltrimethylammonium methosulfate, etc. (11) (meth) Acrylamidohydroxyalkyltrialkylammonium salts such as 3-(meth)acryloylamino-2-
hydroxypropyltrimethylammonium chloride,
3-(meth)aryloylaminoethyl trimethylammonium methosulfate, etc. (4-A) Salts of tertiary nitrogen-containing (meth)acrylamide and acids ([) Salts of dialkylaminoalkyl (meth)acrylamide, such as 2-dimethyl Aminoethyl (meth)acrylamide hydrochloride, 2-diethylaminopropyl (meth)acrylamide sulfate, etc. (Ii) Salts of dialkylaminohydroxyalkyl (meth)acrylamide, such as 3-dimethylamino-2-hydroxypropyl (meth)acrylamide hydrochloride , 3-diethylamino-2-hydroxypropyl (meth)acrylamide sulfate, etc. Among these monomers, preferred from the viewpoint of fluidity and stability over time are monomers (1-A) or (2-A). [In general formula (1), A is an oxygen atom], and more preferably a monomer of (1-A).

Particularly preferred are 2-methacryloyloxyethyltrimethylammonium chloride, 2-methacryloyloxyethyltrimethylammonium methosulfate and dimethylaminoethyl methacrylate sulfate.
The above monomers include nitrogen atom-containing (meth)acrylate or (meth)acrylamide and a quaternizing agent (methyltalolide,
dimethyl sulfate, diethyl sulfate, benzyltalolide, etc.)
Alternatively, it can be easily obtained by reaction with an acid (hydrochloric acid, sulfuric acid, phosphoric acid, acetic acid, para-toluenesulfonic acid, etc.).

In the present invention, the monomer represented by general formula (1) can be used in combination with other vinyl monomers if necessary.

As such other vinyl monomers, hydrophilic monomers that can be mixed with the monomer of general formula (1) and form an aqueous solution can be used. Examples of such hydrophilic monomers include the following (
Monomers such as 1-B) to (3-B) can be mentioned, and one or more of these can be used. (1-
B) Hydrophilic nonionic vinyl monomers: (1) Carbamoyl group-containing monomers such as (meth)acrylamide (
11) Hydroxyl group-containing monomers such as hydroxyethyl (meth)acrylate; (2-B) Hydrophilic cationic vinyl monomers: (1) Tertiary nitrogen atom-containing monomers such as vinylpyrrolidone, vinylpyridine, vinyl Imidazoline, dialkylaminoalkyl (meth)acrylate [
(11) Quaternary nitrogen atom-containing monomers such as dimethyldiallylammonium chloride (3-B) Hydrophilic anionic vinyl monomer (
1) Monomers containing carboxyl groups (or salts thereof) such as (meth)acrylic acid, maleic acid and their sodium salts; (11) Monomers containing sulfo groups (or salts thereof) such as (meth)acryloyloxy Sodium aminodimethylethanesulfonate, etc.

Among these monomers, monomers (1-B) and (2-B) are preferred, and acrylamide and methacrylamide are particularly preferred. In the present invention, an oil-soluble vinyl monomer can also be used in combination, if necessary.

Such monomers include aromatic vinyl monomers such as styrene, α-alkylstyrene (α-methylstyrene, etc.), unsaturated carboxylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, 2-
Ethylhexyl (meth)acrylate; vinyl esters such as vinyl acetate; unsaturated nitrites such as (meth)
Examples include acrylonitrile. The amount of oil-soluble vinyl monomer added is usually 30% or less based on the total monomer amount, and 5% by weight in order to lower the apparent viscosity of the emulsion.
The following are preferred.

The oil-soluble monomer may be blended into the aqueous solution as long as it does not impair its solubility in water, or may be blended into the hydrophobic organic solvent. In the present invention, the amount of the monomer represented by general formula (1) in the total monomers is usually 1% by weight or more, preferably 5 to 100% by weight, and more preferably 20 to 100% by weight. When the monomer represented by general formula (1) is less than 1% by weight, the fluidity of the resulting emulsion J tends to deteriorate. The concentration of all monomers in the aqueous monomer solution is usually 10 to 80% by weight, preferably 40 to 75% by weight.

Hydrophobic organic solvents used in the present invention include hydrophobic aliphatic or aromatic hydrocarbon liquids, vegetable or animal oils, or modified oils of these oils (hydrogenated oils, polymerized oils, etc.). It will be done.

Among these, preferred are aliphatic hydrocarbon liquids such as mineral oil, kerosene, naphtha, paraffin, and isoparaffin, and aromatic hydrocarbon liquids such as benzene, toluene, and xylene; particularly preferred are IP solvents (
Isoparaffin (boiling point usually 160-260℃) such as Idemitsu Petrochemical Co., Ltd. product Isoparaffin (Etsuso Co., Ltd. product)
> is. In the present invention, the ratio of the monomer aqueous solution to the hydrophobic organic solvent is 30 to 70% by weight for the monomer aqueous solution and 70 to 30% by weight for the hydrophobic organic solvent, preferably 50 to 65% by weight for the monomer aqueous solution. %, and the hydrophobic organic solvent is 50-35% by weight.

If the blending amount of the hydrophobic organic solvent (or the total amount of both oil-soluble vinyl monomers if they are included in the solvent) is less than 30% by weight, the stability of the emulsion over time will decrease. If it exceeds 70% by weight, it becomes difficult to stabilize the diluted emulsion solution uniformly, and the price becomes high, which is economically disadvantageous. In the present invention, examples of the nonionic surfactant having an HLB value of 7 or more include those described in (1-C) to (5-C) below, and those having an HLB value of 7 or more. More than one species is used.

(1-C) Polyoxyalkylene derivatives of higher aliphatic alcohols: C8-24 aliphatic alcohols (lauryl mono, cetyl mono, stearyl mono, oleyl mono, any natural alcohol, synthetic alcohol such as lioxo alcohol, Ziegler alcohol) polyoxyethylene derivative (2-
C) Polyoxyalkylene derivative of higher fatty acid: C8
Polyethylene glycol mono- or di-ester (3-C) of ~24 fatty acids (lauric acid, palmitic acid, stearic acid, oleic acid, etc.) Polyoxyalkylene derivative of polyhydric alcohol higher fatty acid ester: C8 ~
Esters (mono-, di-, tri-, ester) polyoxyethylene derivative, (4-C
) Polyoxyalkylene derivatives of phenols: polyoxyethylene derivatives of phenols [alkyl (C8-24) phenols, dialkylphenols, styrenated phenols, etc.], (5-C) polyhydric alcohol higher fatty acid esters: C8-,4 partial esters (mono-esters) of fatty acids (such as lauric acid) and polyhydric alcohols with a valence of 4 or more or their intramolecular anhydrides (pentaerythritol, sorbitol, sol (bitane)). These surfactants can be used alone or in combination with More than one species can be used in combination.

Among these, polyoxyethylene nonionic surfactants are preferred from the viewpoint of excellent appearance and stability of the emulsion, and the most preferred surfactant is (1-C).

The surfactant in the present invention has an HLB value of 7 or more, preferably 8-18, more preferably 8-13.

Such surfactants are so-called oil-in-water emulsifiers that form oil-in-water emulsions. In the present invention, the HLB value of a surfactant can be determined by the method of Mr. Grlffln (Surfactant Handbook, pages 307 to 309). If the HLB value according to Mr. Griffin is 7 or higher, other methods such as Davis (
Davies' method can be used even if the number is less than 7. If the HLB value (glyphin) is less than 7, the appearance is good;
A stable W/0 emulsion cannot be obtained. H.L.
If the B value is too high (greater than 18), it becomes difficult to obtain a W/O emulsion. Furthermore, the HLB value of a surfactant preferable for providing a W/O emulsion having self-phase inversion properties is determined according to the mol% of the monomer represented by general formula (1) in the total amount of monomers. It can be determined from the following formula (2). General formula (1U) (where a is the preferred HLB value, and b is the mol% of the monomer represented by the general formula (1) in the total amount of monomers. show.

) Particularly preferable ones are H that satisfies the general formula (i.e.
polyoxyethylene lauryl ether with LB value,
These are polyoxyethylene oleyl ether, polyoxyethylene cetyl ether, polyethylene glycol monolaurate, and polyethylene glycol distearate.

In the present invention, the amount of surfactant used is 5% (by weight) or more [preferably 8% or more, more preferably 10% or more, particularly preferably 15% or more] and less than 20% (preferably 15% or more) based on the hydrophobic organic solvent. 19% or less, more preferably 1
8% or less].

When the amount of J surfactant exceeds 20%, the apparent viscosity of the emulsion increases and the fluidity rapidly decreases.

As the amount of surfactant decreases (less than 5%), the stability of the emulsion over time decreases. In the present invention, a known method may be used for mixing and emulsifying and dispersing the monomer aqueous solution and the hydrophobic organic solvent using a surfactant.

For example, a method in which a surfactant is added to a hydrophobic organic solvent and a monomer aqueous solution is added while stirring; a method in which a monomer aqueous solution, a hydrophobic organic solvent, and a surfactant are added and stirred; An example of the method is to add a mixed solution of a polymer aqueous solution and a surfactant while stirring. The temperature during stirring is not particularly limited, and is, for example, 30 to 70°C. Further, as a stirring device, a conventional mixing device such as a propeller stirrer, a homogenizer, a static mixer, etc. can be used. The method for polymerizing the emulsified dispersion obtained by the above method may also be a known method, such as a method using a polymerization catalyst, ultraviolet rays, radiation, etc. Examples of the polymerization catalyst include peroxide catalysts such as ammonium persulfate and benzoyl peroxide, and azo compound catalysts such as azobisisobutyronitrile and azobisdimethylvaleronitrile. Among the catalysts, azo compound catalysts are preferred. The amount of the catalyst used is usually 0.01 to 0.5% by weight based on the total monomers, and the polymerization temperature is usually 35 to 90°C, preferably 40 to 70°C. When the polymerization temperature (initiation temperature) is lower than the above, it becomes difficult to obtain a good emulsion. The polymerization is carried out in such a way that the viscosity of an aqueous solution of 1% by weight based on the pure amount of polymer present in the resulting water-in-oil polymer emulsion is at least 100%.
cps or more (30°C, Bruckfield viscometer 1/min
(measured over two revolutions), preferably 200 cps or more. If the viscosity is less than 100 cps, the performance as a wastewater treatment agent will not be fully satisfied. The emulsion-type flocculant of the present invention has a low apparent viscosity, usually 100 cp when measured at a polymer concentration of 30% by weight in the emulsion.
s or less (measured at 30° C. with a Bruckfield viscometer at 12 revolutions per minute), and in most cases 50 cps or less, and has extremely high fluidity, so it can be advantageously transferred to a dilution tank or the like.

Fully automated equipment can also be used depending on practical needs. Also, when diluting it by adding it to water,
Phase inversion can be performed extremely quickly compared to those with higher apparent viscosity without using phase inversion accelerators, and work efficiency is significantly improved. It can be used as it is or diluted with water to an appropriate concentration (polymer concentration usually 0.01 to 2.0 (Ff), preferably 0.05 to 1f)) for use in sewage, human waste, and water supply rivers. Water, wastewater from mining and other industries (dyeing wastewater,
Paper/pulp industry wastewater, leather industry wastewater, metal smelting wastewater, bottling factory wastewater, facial dye manufacturing wastewater; chemical, pharmaceutical, cosmetics, and other organic and inorganic industrial wastewater, mountain gravel extraction wastewater, mineral processing wastewater, industrial sludge-containing wastewater, Coagulation (sedimentation promotion,
(clarification, solid-liquid separation, acceleration of dehydration). When used as a flocculant, the amount used varies depending on the type of object, concentration, etc., but it is usually used in an amount of 0.005 to 0.2% based on the weight of solid particles in the suspension as a polymer. . The present invention will be further explained below with reference to Examples, but the present invention is not limited thereto.

Production Example 1 1759 3-methacryloyloxypropyl dimethylethyl z-ammonium methosulfate (M-1) and 175f1 of acrylamide (CM-1) were mixed with 230 g of distilled water.
9 to obtain a monomer aqueous solution.

Separately, put n-hexane 3609 into a three-bottle flask, dissolve polyethylene glycol (MW6OO) dioleate (HLB value 10.4) 609 (16.7% by weight based on n-hexane), and continue stirring. 1/3 of the previously prepared aqueous monomer solution was added and emulsified to obtain an emulsion. Nitrogen gas was passed through this emulsion for 30 minutes, and while stirring while keeping the temperature at 50°C on a water bath, a 10% by weight acetone solution of azobisdimethylvaleronitrile (catalyst solution) was prepared.
Add 1m1. Then, polymerization started.

After stirring for 1 hour, add 2ml of the above catalyst solution to the remaining monomer aqueous solution.
was added dropwise to the reaction flask from a dropping load.

The dropwise addition took 2 hours, and stirring was continued for another 1 hour, and 3 ml of the above catalyst solution was added. After stirring at 50° C. for 2 hours, the mixture was allowed to cool to obtain a fluid polymer emulsion (Product 1 of the present invention) with a viscosity (Type B viscosity, 30° C., 12 revolutions per minute, hereinafter the same) of 62 cps.

The viscosity of this 1% by weight aqueous solution based on the pure polymer content is 2300c.
It was ps. Comparative Product Manufacturing Examples 1 and 2 Comparative emulsions were obtained in the same manner as in Example 1 and according to the conditions shown in Table 1.

The viscosity of the obtained polymer emulsion and the viscosity of an aqueous solution of 1% by weight of the polymer are also listed in Table 1. Production Example 2 In Example 1, 2-methacryloyloxyethyltrimethylammonium chloride (M-
2) 2459 and methacrylamide (CM-2) 10
A polymer emulsion (product of the present invention 2) was obtained in the same manner as in Example 1, except that an aqueous monomer solution in which 51 was dissolved in 230 f1 of distilled water was used.

The viscosity of this polymer emulsion and that of the 1% by weight aqueous polymer solution were X83 cps and l89 Ocps, respectively. This polymer emulsion was highly fluid. Example 1 and Comparative Example 1 [Test example as flocculant] The polymer emulsions obtained in the production examples of the products of the present invention and the production examples of comparative products were diluted with water to prepare solutions with a polymer concentration of 0.2%.

The following agglutination test was conducted on the sample after a certain period of time after dilution. Mixed sludge of initial settling sludge and surplus sludge in sewage treatment (PH6.2, SS: 2.23%, VSS: 6
6.2% [to Ss]) was taken, and a water diluted solution of the polymer emulsion was added thereto as shown in Table 2 to cause agglomeration. The agglomeration stirring conditions are a hand mixer (1 heater)
250r. p. m. The mixture was stirred for 20 seconds at a circumferential speed of 0.5 m/Sec. Next, the flocculated sludge was poured onto a Buchner funnel lined with a 100-mesh nylon filter cloth, and
The amount of filtrate after 0 seconds was measured. In addition, the sludge after filtration was
Filter cloth for belt press dehydrator (polyester,
The sludge was sandwiched between a herringbone (herringbone and twill weave) and a sponge and squeezed for 2 minutes at a pressure of 0.5 kg/d, and then the releasability and water content of the sludge were measured.

The peelability is the percentage of the weight of the wet cake that can be peeled off when the filter cloth is peeled off.

The above results are summarized in Table-2. Table 2 As shown in Table 2, the product of the present invention acts effectively as a flocculant.

On the other hand, the comparative product does not work effectively due to poor phase inversion. Table 3 As shown in Table 3, the present invention works effectively as a freeness improver for paper manufacturing.

Claims (1)

[Claims] 1 General formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, R
_1 is H or CH_3; R_2 and R_3 are each independently an alkyl group having 1 to 4 carbon atoms, or a hydroxyalkyl group having 2 to 4 carbon atoms; R_4 is H, an alkyl group having 1 to 4 carbon atoms, or a hydroxyalkyl group having 2 to 4 carbon atoms; 4 hydroxyalkyl group or benzyl group; A is an oxygen atom or NH; B has 1 to 1 carbon atoms
4 alkylene group or a hydroxyalkylene group having 2 to 4 carbon atoms; X^- is an anionic counterion. 80 to 70% by weight of an aqueous solution of a monomer represented by () or a mixture of this and other vinyl monomers and 70 to 30% by weight of a hydrophobic organic solvent. The polymer is emulsified and dispersed in the presence of a nonionic surfactant having an HLB value of 7 or more in an amount of 5% by weight or more and less than 20% by weight, so that the viscosity of a 1% by weight aqueous solution of the polymer is at least 100c.
An emulsion-type flocculant with good fluidity that is polymerized to form PS... 2 The monomer represented by general formula (I) is represented by general formula (II)▲
There are mathematical formulas, chemical formulas, tables, etc. ▼ (II) (In the formula, R_1
is H or CH_3; R_2 and R_3 are each independently an alkyl group having 1 to 4 carbon atoms; or a hydroxyalkyl group having 2 to 4 carbon atoms; R_4 is H, an alkyl group having 1 to 4 carbon atoms, or a hydroxyalkyl group having 2 to 4 carbon atoms; is a hydroxyalkyl group or a benzyl group; B is an alkylene group having 1 to 4 carbon atoms or a hydroxyalkylene group having 2 to 4 carbon atoms; X^- is an anionic counter ion; ) The emulsion-type flocculant according to claim 1, which is a monomer represented by...