JP3513754B2 - Antimony removal method and remover - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method and a removing agent for removing antimony contained in water.

[0002]

2. Description of the Related Art Conventionally, a coagulation sedimentation method has been used as a method for treating metal-containing wastewater discharged from a non-ferrous smelter or factory, but antimony in the wastewater cannot be removed. Especially at low concentrations, it was extremely difficult. In recent years, the importance of solving the problem of environmental pollution due to industrial wastewater and the like has led to strong demand for effective removal methods of harmful substances such as antimony.

[0003]

Therefore, an object of the present invention is to provide a method for efficiently removing antimony and an antimony remover used for the method.

[0004]

The present inventors have completed the present invention as a result of intensive studies to solve the above problems. That is, according to the present invention, contained in water to be treated
In the method for removing antimony,
On, ( ii ) iron ion, calcium ion, magnesium
Harmless selected from mu ion and aluminum ion
Polyvalent metal ion and ( iii ) carboxyl group-containing parent
Aqueous polymeric substance and / or its hydrolysis products are added
The pH of the water to be treated within the range of 6 to 12
To precipitate the antimony as a sparingly soluble substance
An antimony removal method is provided. Further, according to the present invention, antimony contained in the water to be treated is
And ( ii ) a phosphoric acid compound and ( ii )
Hydrophilic polymer containing carboxyl group and / or addition thereof
Antimony removal characterized by consisting of water decomposition products
Remover is provided. Furthermore, according to the present invention, the water to be treated is
A drug that removes antimony contained in
(I) Phosphoric acid compound and ( ii ) Carboxyl group-containing hydrophilicity
Polymeric substances and / or their hydrolysis products and ( iii ) iron
Compounds, calcium compounds, magnesium compounds and
Harmless polyvalent metal compound selected from among luminium compounds
Antimony remover characterized by consisting of
To be done.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION One embodiment of the antimony removing agent (hereinafter, also simply referred to as a removing agent) of the present invention is (i) a phosphoric acid compound and (ii) a carboxyl group. It is composed of a mixture of the contained hydrophilic polymer substance and / or its hydrolysis product. Another aspect of the removing agent according to the present invention (hereinafter, also simply referred to as removing agent B) is (i) a phosphoric acid compound and (ii) a carboxyl group-containing hydrophilic substance and / or a hydrolysis product thereof (iii). ) Consisting of a mixture with harmless polyvalent metal compounds. The removing agent of the present invention is usually used in the form of powder or aqueous solution.

Phosphoric acid compounds include, in addition to phosphoric acid (H ₃ PO ₄ ), compounds that hydrolyze in water to produce phosphoric acid, such as sodium phosphate, disodium hydrogen phosphate, sodium dihydrogen phosphate. , Potassium phosphate, dipotassium hydrogen phosphate, potassium dihydrogen phosphate, sodium hexane metaphosphate, sodium tripolyphosphate and the like.

The harmless polyvalent metal compounds include iron compounds, calcium compounds, magnesium compounds, aluminum compounds and the like. Specific examples of these are:
For example, ferrous chloride, ferric chloride, ferrous sulfate, ferric sulfate, polyiron chloride, polyiron sulfate, calcium chloride, calcium hydroxide, calcium carbonate, aluminum chloride, aluminum sulfate, polyaluminum chloride, etc. Is mentioned.

The carboxyl group-containing hydrophilic polymer substance includes various water-soluble polymer substances. Such polymeric substances include alginic acid, dielan gum, xanthan gum, pectin, pectic acid, pectinic acid,
Examples thereof include polysaccharides such as anionized starch, propylene glycol alginate, carboxymethyl cellulose, starch glycolic acid and fibrin glycolic acid, and metal salts thereof. In the present invention, it is particularly preferable to use sodium alginate or calcium alginate, but when this is used, the content ratio (molar ratio) of mannumaronic acid (M) and guluronic acid (G) constituting alginic acid [ It is preferable to use one having M] / [G] in the range of 0.1 to 4.0, preferably 0.1 to 3.
The higher the content ratio of guluronic acid, the better the floc forming property. The carboxyl group-containing hydrophilic polymer substance and / or its hydrolysis product used in the present invention can be used alone or in the form of a mixture. As the mixture, it is preferable to use a mixture containing alginic acid or a salt thereof.

The carboxyl group-containing hydrophilic polymer substance and / or its hydrolysis product used in the present invention can be used alone or in the form of a mixture. In this case, a preferable mixture containing alginic acid or a salt thereof includes (i) alginic acid or a salt thereof and (ii) at least one selected from dielan gum, xanthan gum, pectin, pectic acid, pectinic acid and salts thereof. And a mixture of the above-mentioned hydrophilic polymer substances. When the mixture ratio is shown, for example, when a mixture of sodium alginate and another carboxyl group-containing hydrophilic polymer substance is used, sodium alginate (A) and another carboxyl group-containing hydrophilic polymer substance (B) are used. The weight ratio [A] / [B] is 1 to 100, preferably 2 to 50.

In the case of producing the removing agent A,
The phosphoric acid compound and the harmless polyvalent metal compound may be mixed. In this case, the proportion of harmless polyvalent metal compound, when the treated water does not contain a harmless polyvalent metal compound,
0.1 to 200 moles, preferably 0.1 to 200 moles per mole of phosphorus.
It is a ratio of 1 to 100 mol. When the water to be treated contains a sufficient amount of the harmless polyvalent metal compound, it is possible to omit the use of the harmless polyvalent metal compound in the production of the removing agent A, and to include a certain amount. If so, the amount of the harmless polyvalent metal compound in the removing agent A can be reduced corresponding to the amount contained in the water.

In order to preferably produce the removing agent B of the present invention, first, a hydrophilic polymer substance containing a carboxyl group is heated in water containing an alkaline substance to be hydrolyzed and dissolved in water. For example, sodium alginate is present in water containing sodium hydroxide as an alkaline substance and heated to dissolve the sodium alginate. The heating temperature at this time is preferably not lower than 70 ° C. and lower than 100 ° C., more preferably 75 ° C. to 90 ° C., further preferably 80 ° C. to 8 ° C.
It is 5 ° C. The heating time is not particularly limited as long as the carboxyl group-containing hydrophilic substance is dissolved, but is not limited to 0.5 hours to 2 hours. Next, the phosphoric acid compound and the harmless polyvalent metal compound are mixed with the alkaline aqueous solution containing the obtained carboxyl group-containing hydrophilic polymer substance and / or its hydrolysis product.

The ratio of the carboxyl group-containing hydrophilic polymer substance and / or its hydrolysis product and the phosphoric acid compound in the removing agent of the present invention is not particularly limited, but generally, the carboxyl group-containing hydrophilic polymer is used. 10 parts by weight of phosphoric acid compound to 1 part by weight of the substance and / or its hydrolysis product
The amount is from 1 to 10,000 parts by weight, preferably from 50 to 5,000 parts by weight, more preferably from 100 to 5,000 parts by weight.

In order to remove antimony in the water to be treated according to the present invention, the pH may be adjusted to 6 to 12, preferably 7 to 11 in the presence of phosphate ions and harmless polyvalent metal ions. If sufficient harmless polyvalent metal ions are present in the water, it is not necessary to add a harmless polyvalent metal compound. On the other hand, if the harmless polyvalent metal ion does not exist in water or the amount is not sufficient, a harmless polyvalent metal compound giving a harmless polyvalent metal ion, for example, ferrous chloride, ferric chloride, sulfuric acid. Ferrous iron, ferric sulfate, polyiron chloride, polyiron sulfate, calcium chloride, calcium hydroxide, calcium carbonate, aluminum chloride, aluminum sulfate, polyaluminum chloride, etc. may be added. In this case, an alkaline substance is usually used as the pH adjuster, and it is preferable to use calcium hydroxide or sodium hydroxide as the alkaline substance. The ratio of phosphate ion to harmless polyvalent metal ion is 0.1 to 200 moles of harmless polyvalent metal, preferably 0.1 to 100 moles, relative to 1 mole of phosphorus.
The molar ratio is more preferably 0.1 to 50 mol.

The proportion of the phosphoric acid compound is 1 to 5000 mol, preferably 1 to 1 mol, per 1 mol of antimony in the water to be treated.
The amount is 3000 mol, more preferably 1 to 2000 mol.

In the present invention, in the water to be treated,
It is preferable to allow a carboxyl group-containing hydrophilic polymer substance and / or a hydrolysis product thereof to be present. The proportion is
The amount is 0.0001 to 0.1 part by weight, preferably 0.0001 to 0.01 part by weight, and more preferably 0.0001 to 0.01 part by weight, per 1 part by weight of the phosphoric acid compound.

When antimony contained in the water to be treated is to be removed according to the present invention, if the water to be treated is acidic or neutral, it is preferable to adjust the pH so as to cause precipitation after addition of the removing agent. Its pH is generally in the range 6-12, preferably in the range 7-11.

When antimony contained in the water to be treated is removed by the present invention, flocs can be grown by changing the water to be treated from neutral to alkaline.

In the present invention, it is preferable to use a coagulant together. The aggregating agent in this case is used for floc aggregating, and examples thereof include cationized modified polyacrylamide, polyacrylic acid dimethylaminoethyl ester, polymethacrylic acid dimethylaminoethyl ester, Includes cationic organic flocculants such as polyethyleneimine and chitosan, nonionic organic flocculants such as polyacrylamide, anionic organic flocculants such as polyacrylic acid, copolymers of acrylamide and acrylic acid, and salts thereof. To be done. The amount of the flocculant used is 1 to 20 mg / L, preferably 3 to 10 in terms of concentration in water.
It is mg / L.

The water to be treated containing flocs after the pH adjusting step is subjected to solid-liquid separation treatment. Examples of the solid-liquid separation method in this case include conventional methods such as filtration separation, centrifugation and sedimentation separation.

The water to be treated used in the present invention contains antimony, and various factory effluents are used. The concentration of antimony in the water to be treated is not particularly limited, and it is possible to treat wastewater containing high to low concentrations of antimony to an extremely low concentration.

[0021]

According to the method of the present invention, antimony contained in water as water to be treated can be efficiently removed.

[0022]

EXAMPLES Next, the present invention will be described in more detail by way of examples.

Reference Example 1 In a 500 ml beaker, 2% sodium alginate aqueous solution was added to 300 ml of 1N NaOH, and then 75
The mixture is heated to ℃ to 85 ℃ and stirred for 30 minutes to 1 hour. The agitated aqueous solution was allowed to cool to room temperature (25 to 35 ° C.) and then in a 10 L beaker, 300 ml of the room temperature sodium alginate aqueous solution and 85% phosphoric acid aqueous solution were added.
700 ml was mixed. Thus, the removing agent A of the present invention was obtained.

Reference Example 2 Removal agent A and industrial ferric chloride (37.5% aqueous solution) were mixed at a volume ratio of 1:27 to obtain removal agent B of the present invention.

Example 1 Remover A was added to actual wastewater containing 0.2 ppm of antimony.
After adding 100 ppm and stirring for 2 minutes, ferric chloride (3
(7.5% aqueous solution) 2660 ppm was added and stirred for 2 minutes. Add calcium hydroxide (10% aqueous slurry) to this liquid
The pH was adjusted to 9 by adding 1500 ppm. Next, polymer flocculant Diafloc (AP120C) is added to 3 ppm.
After adding and stirring, the obtained precipitate was solid-liquid separated. When the concentration of antimony in the treatment liquid was measured by a hydride generation ICP emission spectroscopy analyzer, it was 0.010 ppm.

Comparative Example 1 Ferric chloride (37.5% aqueous solution) was added to the actual waste water of Example 1.
2660 ppm was added and stirred for 2 minutes. 1500 ppm of calcium hydroxide (10% aqueous slurry) was added to this solution to adjust the pH to 9. Next, after adding 3 ppm of polymer flocculant Diafloc (AP120C) and stirring, the obtained precipitate was separated into solid and liquid. When the concentration of antimony in the treatment liquid is measured with an ICP device, it is 0.108 ppm
Met.

Example 2 To the actual wastewater of Example 1, 100 ppm of the remover A was added and stirred for 2 minutes, and then ferric chloride (37.5% aqueous solution) 260
0 ppm was added and stirred for 2 minutes. 740 ppm of calcium chloride (30% aqueous solution) was added to this solution and stirred for 2 minutes. The pH was adjusted to 9 by adding aqueous sodium hydroxide solution. Next, polymer flocculant Diafloc (AP12
0 C) was added at 3 ppm and stirred, and then the obtained precipitate was subjected to solid-liquid separation. When the concentration of antimony in the treatment liquid was measured by an ICP device, it was 0.013 ppm.

Example 3 50 ppm of the remover A was added to the actual wastewater of Example 1 and 2
After stirring for 1 minute, ferric chloride (37.5% aqueous solution) 2660
ppm was added and stirred for 2 minutes. Add 1350 ppm of calcium hydroxide (10% aqueous slurry) to this solution and add
The H was adjusted to 9. Next, after adding 3 ppm of polymer flocculant Diafloc (AP120C) and stirring, the obtained precipitate was separated into solid and liquid. When the concentration of antimony in the treatment liquid was measured by an ICP device, it was 0.017 ppm.

Example 4 2660 ppm of the remover B was added to the actual wastewater of Example 1 and stirred for 2 minutes. Calcium hydroxide (10%
Aqueous slurry) (1500 ppm) was added to adjust the pH to 9. Next, polymer flocculant Diaflock (AP120
After adding 3 ppm of C) and stirring, the obtained precipitate was subjected to solid-liquid separation. When the concentration of antimony in the treatment liquid was measured by an ICP device, it was 0.014 ppm.

─────────────────────────────────────────────────── ─── Continuation of the front page (73) Patent holder 000005979 Mitsubishi Corporation 2-3-6 Marunouchi, Chiyoda-ku, Tokyo (74) The above three agents 100074505 Patent Attorney Toshiaki Ikeura (72) Inventor Kenji Tatsumi 16-3 Onogawa, Tsukuba, Ibaraki, Institute of Natural Resources and Environmental Technology, Institute of Industrial Technology (72) Inventor, Shinji Wada, 16-3, Onogawa, Tsukuba, Ibaraki, Institute of Resources, Environmental Technology (72) Inventor, Yasuhiro Yukawa, Ibaraki 2-1-6 Sengen, Tsukuba City, Japan Mitsubishi Corporation Project Development Department, Environmental Resources Laboratory (56) Reference JP 2000-317467 (JP, A) JP 63-236592 (JP, A) JP 62- 164838 (JP, A) JP 61-291095 (JP, A) JP 61-4515 (JP, A) JP 60-71083 (JP, A) JP 56-70893 (JP A) Patent flat 11-347568 (JP, A) JP flat 1-236202 (JP, A) WO 99/031017 (WO, A1) (58 ) investigated the field (Int.Cl. ^7, DB name) C02F 1/62

Claims (8)

(57) [Claims] 1. Removal of antimony contained in water to be treated
In the method, (i) phosphate ion, ( ii ) iron ion
Ion, calcium ion, magnesium ion and aluminum
Harmless polyvalent metal ion selected from the aluminum ion,
And ( iii ) a carboxyl group-containing hydrophilic polymer substance and
And / or a hydrolysis product thereof is added to be present,
Adjust the pH of the water to be in the range of 6-12,
Is characterized by precipitating as an insoluble substance.
How to remove mon. 2. The harmless polyvalent metal ion is an iron ion or an iron ion.
And / or calcium ions. 3. A carboxyl group-containing hydrophilic polymer substance
Is (i) alginic acid or a salt thereof or ( ii ) algi
Highly hydrophilic with acid or its salt and other carboxyl groups
A method according to claim 1 or 2 comprising a mixture with a molecular substance. 4. A coagulant is added to the water.
Either way. 5. Removal of antimony contained in water to be treated
Which comprises a (i) phosphate compound and ( ii ) carbohydrate
Hydroxyl group-containing hydrophilic polymer substance and / or hydrolysis thereof
An antimony remover comprising a product. 6. Removal of antimony contained in water to be treated
Which comprises a (i) phosphate compound and ( ii ) carbohydrate
Hydroxyl group-containing hydrophilic polymer substance and / or hydrolysis thereof
Products and ( iii ) iron compounds, calcium compounds, Magne
Selected from sium compounds and aluminum compounds
An ann characterized by comprising a harmless polyvalent metal compound
Zimon remover. 7. The carboxyl group-containing hydrophilic polymer substance
Is (i) alginic acid or a salt thereof or ( ii ) algi
Highly hydrophilic with acid or its salt and other carboxyl groups
The removing agent according to claim 5 or 6, which comprises a mixture with a molecular substance. 8. The phosphoric acid compound is phosphoric acid.
The removing agent according to any one of 5 to 7.