WO2005075363A1

WO2005075363A1 - Borofluoric acid-trapping agent and method of treating wastewater with the same

Info

Publication number: WO2005075363A1
Application number: PCT/JP2005/001984
Authority: WO
Inventors: Akira Yoshida; Yoshinori Iizawa
Original assignee: Chugai Photo Chemial Co., Ltd.
Priority date: 2004-02-10
Filing date: 2005-02-03
Publication date: 2005-08-18
Also published as: TW200535555A; JP4682043B2; JPWO2005075363A1

Abstract

A wastewater which contains a borofluoric acid salt and is discharged by a plater, glass processor, printed-wiring-board manufacturer, etc. can be made to be extremely easily treated efficiently with an existing apparatus at ordinary temperature in a short time while preventing sludge generation. The wastewater treatment can be attained with a borofluoric acid-trapping agent represented by the following general formula (1) or (2). General formula (1) (1) R1 to R4 each independently represents C1-24 alkyl, alkenyl, phenyl, or benzyl, provided that R1 to R4 may be bonded to one another to form a ring; and X- represents an anion. General formula (2) (2) R1 to R4 each independently represents C1-24 alkyl, alkenyl, phenyl, or benzyl, provided that R1 to R4 may be bonded to one another to form a ring; and A represents an anionic polymer.

Description

Borofluoric acid scavenger and wastewater treatment method using the same

Technical field

The present invention relates to a process for treating wastewater containing borofluoride.

The present invention relates to an additive and a method for treating the same, and

The present invention relates to a treatment method for treating wastewater containing citrate in a short time without heating with external energy.

Background art

Fluorine compounds represented by hydrofluoric acid are valuable substances that are used in large quantities in industries such as chemical plants, semiconductor manufacturing, metal processing, glass processing, and plating. Due to its harmfulness, wastewater containing them has emission standard values, and strict emission regulations are being enforced. As a general method for removing fluorine from wastewater, calcium compounds such as slaked lime and calcium chloride are added to fluorine-containing wastewater, and the pH is adjusted to precipitate hardly soluble calcium fluoride. The method of solid-liquid separation is adopted.

However, when the fluorine compound in the wastewater exists as borohydrofluoride, even if the calcium compound is added, the hardly soluble compound is not generated, so that it is difficult to remove the fluorine.

In addition, emission standards are set for boron because of its harmfulness, and it is necessary to remove boron from wastewater when discharging.

A common method for removing boron is to use a calcium compound and aluminum compound. A method is known in which a hardly soluble compound is formed depending on the substance, and sedimentation is separated. However, also in the case of boron, as in the case of fluorine, it is difficult to remove boron when boron is present as borofluoride.

To solve these problems, the following technology is disclosed as a method for treating borofluoride.

(1) A method in which an aluminum compound or a ferric salt is added to decompose borofluoride, and then a calcium compound is added to remove generated calcium fluoride (Japanese Patent Publication No. 54-180806) No. 4).

(2) A method in which an aluminum compound is added to thermally decompose borohydrofluoride in an acidic region, and then a calcium compound is added to remove calcium fluoride generated (Japanese Patent Laid-Open No. 62-227). No. 496).

(3) Aluminum sulfate is added to waste water containing borofluoride and reacted at 50 ° C or more to decompose borofluoride ions, and then calcium carbonate is added to fix fluorine as calcium. ■ Removal method (see Japanese Patent Publication No. Hei 7—3 286 645).

However, all of these methods require heating to accelerate the decomposition of the borofluoride. In addition, the non-heating treatment had problems such as requiring a long disintegration time.

If a large excess of the aluminum compound is used, the removal of fluorine is enhanced, but this causes a large amount of sludge, and the disposal method becomes a problem. Disclosure of the invention

The present invention solves the above-mentioned drawbacks of the conventional treatment method, and provides a treatment agent capable of treating borohydrofluorate-containing wastewater at ordinary temperature and in a short time without generating a large amount of sludge. It is to provide a processing method. The object of the present invention is solved by the following means (1) to (9).

(1) An additive for removing borofluoric acid from wastewater, comprising at least one compound represented by the following general formulas (1) to (4).

General formula (1)

,

R i to R ₄ each independently represent an alkyl group, an alkenyl group, a phenyl group or a benzyl group having 1 to 24 carbon atoms, and RR may be linked to each other to form a ring. A represents an anionic polymer.

General formula (3) z,

_R1 one ⁺ NZX one

C '

R i is an alkyl group having 1 to 24 carbon atoms, an alkenyl group, a phenyl group or Represents a benzyl group. Z represents an atomic group necessary for constituting a hetero ring. X- represents an anion.

General formula (4)

Ri― "Z

AR represents an alkyl group having 1 to 24 carbon atoms, an alkyl group, a phenol group or a benzyl group. Z represents an atomic group necessary for constituting a hetero ring. A represents an anionic polymer.

(2) — The means of (1), wherein A of the borofluoric acid scavenger represented by the general formulas (2) and (4) has a structure selected from the following group A. The borohydrofluoric acid scavenger as described in the above.

Group A: Alginic acid, pectin, gelatin, anionized starch, carboxymethylcellulose, polyacrylic acid, copolymer of acrylamide and acrylic acid

(3) It is characterized in that the mole number of the anionic moiety of the anionic polymer is from 0.01 to 5.0 moles per mole of the quaternary ammonium salt. The borofluoric acid scavenger according to the means.

(4) A wastewater treatment method for removing borofluoric acid from wastewater containing borohydrofluoric acid, the method comprising the steps of: capturing fluorinated acid represented by the following general formula (1) or (3) in the wastewater; Wastewater treatment method characterized by adding at least one kind of agent.

General formula (1)

R i to R ₄ each independently represent an alkyl group, alkenyl group, phenyl group or benzyl group having 1 to 24 carbon atoms, and R ₄ to R ₄ may be linked to each other to form a ring. X— represents an anion. (6) After adding at least one of the borofluoric acid scavengers represented by the general formula (1) or (3), diatomaceous earth, bentonite, kaolin, activated carbon, po / le-trandoseme Wastewater treatment as described in (4) or (5), wherein at least one compound selected from the group consisting of a polymer, a hydrophilic polymer compound, a polyvalent metal, and a rare earth compound is added. Method.

(7) The wastewater treatment method as described in the means (6), wherein the amount of the conjugation product is 0.0005 to 5.0% by weight of the water to be treated.

(8) Wastewater treatment characterized by contacting wastewater containing borofluoride with a borofluoric acid scavenger represented by the general formula (2) or (4) below ρΗ5 Method.

General formula (2)

R ~ ₄ f or each independently an alkyl group with carbon number 1-2 4, an alkenyl group, an Fueyuru group or a benzyl group, it may also form a form a ring R i R each other les. A represents an aionic polymer selected from Group A below.

Group A: a / reginic acid, pectin, gelatin, aeonized starch, cal. Boxymethizolesenorelose, polyacrylic acid, copolymer of acrylamide and acrylic acid

General formula (4)

R represents an alkyl group having 1 to 24 carbon atoms, an arcel group, a fuel group or a benzinole group. Z represents an atomic group necessary for constituting a hetero ring.

A represents an anionic polymer.

(9) Regarding the method for regenerating the borofluoric acid scavenger represented by the following general formula (2) or (4), contact the scavenger trapping borofluoric acid with an aqueous solution adjusted to pH 8 or more A method for regenerating a borofluoric acid scavenger, characterized in that the regenerating is performed by causing the fluorinated acid to be regenerated.

General formula (2)

R i to R ₄ each independently represent an alkyl group having 1 to 24 carbon atoms, an alkyl group, a phenyl group or a benzyl group, and R i to R ₄ are connected to each other to form a ring; Is also good. A represents an ionic polymer.

General formula (4)

Ri— + NZ A Ri represents an alkyl group having 1 to 24 carbon atoms, an alkenyl group, a phenyl group or a benzinole group. Z represents an atom group necessary for constituting a hete ring.

A represents an anionic polymer.

By using the borofluoric acid scavenger of claims 1, 2, and 3 of the present invention, a small amount of sludge can be obtained from wastewater containing borofluoride without using external energy such as heating. Fluorine and boron in a short time Can be removed. In addition, there is no need to reinforce equipment such as installing a tank for secondary treatment (advanced treatment), and advanced treatment can be performed using only existing primary treatment equipment.

According to claims 4 and 5 of the present invention, the above-mentioned effects can be obtained, and the intended purpose can be achieved by extremely simple operation and use of the conventional equipment as it is.

According to claims 6 and 7 of the present invention, solid solution separation can be efficiently performed by sedimentation of the inert compound. In addition, the flocculence of the floc is increased, and the sludge volume can be reduced.

According to claim 8 of the present invention, by performing contact drainage at a pH of less than 5, the efficiency of the removing agent can be further improved.

Furthermore, according to the ninth aspect of the present invention, the scavenger can be regenerated very efficiently, and a very economical borofluoride decomposition treatment can be performed. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail.

The wastewater treatment method of the present invention is intended for wastewater containing borofluoride. Wastewater containing borohydrofluoric acid is discharged from, for example, metalworkers, glass processors, printed circuit board processors and metal surface treatment companies.

The present invention is characterized in that borofluoric acid scavengers represented by the following general formulas (1) to (4) are added to waste water containing borofluoride. Furthermore, the method is characterized in that a scavenger represented by the general formula (2) or (4), which has trapped borofluoric acid, is regenerated by contacting the scavenger with an aqueous solution adjusted to pH 8 or more.

General formula (1)

General formula (2)

In the quaternary ammonium salts represented by the above general formulas (1) and (2), R i to R ₄ are each independently an alkyl group having 1 to 24 carbon atoms, an alkyl group, a phenyl group or Represents a benzyl group, and R to shaku may be linked to each other to form a ring. At least one of R i to R ₄ preferably has an anoalkyl group or an anorecenyl group having 12 or more carbon atoms.

General formula (3)

RT N Z X

C '

R represents an alkyl group having 1 to 24 carbon atoms, an alkenyl group, a phenyl group or a benzyl group. Z represents an atomic group necessary for constituting a hetero ring. X represents an anion.

General formula (4) Ri— ⁺ NZA

W _C no

R represents an alkyl group having 1 to 24 carbon atoms, an alkenyl group, a phenyl group or a benzyl group. Z represents an atomic group necessary for constituting a hetero ring. A represents an anionic polymer.

Specific examples of the quaternary ammonium salt used in the present invention include dimethylstearenol-benzinoleum ummonium chloride, trimethyl lanyl ammonium ummonium chloride, and trimethyl cetyl ummonium chloride. Trimethylsilyl armonium chloride, dimethinoresistorinoleammonium chloride, dimethinoreggioleinoleammonium chloride, methyl chloride tridodecinoleammonium chloride, benzalkonium chloride, 1-stearyl-1,4,4-trimethylbiperazinium and the like can be mentioned, but not limited thereto.

X in the general formula (1) represents an anion. The anion, F-, CI -, B-, I-, S 0 4 2 -, N 0 3 2 -, C 0 3 2 -, P 0 4 2 - and the like can Rukoto cited.

A in the general formula (2) represents an anionic polymer. Specific examples of the aionic polymer include alginic acid, pectin, gelatin, anionized starch, carboxymethylcellulose, polyacrylic acid, and copolymers of acrylamide and acrylic acid. Any material can be used as long as it forms a counter-ion with the quaternary ammonium salt represented by the general formula (2) to form a poorly water-soluble solid.

General formula (3)

General formula (4)

Ri ⁺ A

In the nitrogen-containing heterocyclic compound having a nitrogen quaternized by a substituent represented by the general formulas (3) and (4), R i is an alkyl group having 1 to 24 carbon atoms and alkenyl, respectively. Represents a group, a fuel group or a benzyl group. In particular, those having an alkyl or alkenyl group having 8 or more carbon atoms are preferable, and those having an alkyl group or an alkyl group having 12 or more carbon atoms can be suitably used. Z represents an atom group necessary for constituting a hetero ring, and is particularly preferably an atomic group necessary for constituting a pyridyl ring. Specific examples of the nitrogen-containing heterocyclic compound having a nitrogen quaternized by a substituent used in the present invention include laurylpyridinium chloride, cetylpyridinum chloride, and 1-stearyl 1H-base. But not limited thereto.

The amount of the borofluoric acid scavenger represented by the general formula (1) or (3) is 0.1 to 5.0, preferably 0.2, per mole of borofluoric acid ions contained in the wastewater. The amount is 5 to 2.5 moles, more preferably 0.5 to 2.0 moles, and may be added in accordance with the desired removal rate of hydrofluorofluoride. By adding borofluoric acid scavenger [Q] + X— represented by the general formula (1) or (3) to the water to be treated, borofluoric acid and an insoluble compound are formed. To achieve.

[Q] ⁺ X ^_ + Na + BF ₄ — → [Q] + BF ₄ — l + Na X

After the treatment in the above process, solid-liquid separation into treated water and insoluble compounds makes it possible to remove borofluoride from wastewater. As a method of solid-liquid separation, sedimentation separation, press filtration, centrifugal filtration, centrifugation, and the like are used.

In the present invention, diatomaceous earth, bentonite, kaolin, activated carbon, Portland cement, and hydrophilic high-molecular-weight compound are used to precipitate the insoluble compounds of borofluoride and quaternary ammonium salt and efficiently perform solid-liquid separation. It is preferable to add at least one compound selected from molecular compounds, polyvalent metals, and rare earth compounds. These compounds may be used alone or as a mixture of a plurality of compounds. The addition amount of these compounds is 0.0 0 0 5 5 treated water 0 wt ^_0/0, preferably 0.0 0 1 to 3.0 wt ^_0/0, more preferably 0.0 0 5 to 2.0% by weight.

Specific examples of the hydrophilic polymer compound used in the present invention include alginic acid, pectin, gelatin, agar, anionized starch, carboxymethylcellulose, polyacrylic acid, polyethyleneimine, polyacrylamide, Examples include, but are not limited to, copolymers of acrylamide and acrylic acid and metal salts thereof, aluminum polychloride, polyiron sulfate, and polyiron chloride. Both natural products and synthetic products can be used, but those having biodegradability are preferable from the viewpoint of environmental protection.

Examples of the polyvalent metal used in the present invention include iron compounds such as iron chloride and iron sulfate, aluminum compounds such as aluminum chloride and sulfate bands, and zinc compounds such as zinc chloride and zinc sulfate. It is not done.

The rare earth compounds used in the present invention include cerium, lanthanum, Chloride, sulfate, nitrate, acetate such as sodium, prasedium, samarium, gadolinium, terbium, yttrium, etc., but are not limited thereto.

By adding these compounds, the flocculence of the floc is increased, and the volume of sludge can be reduced.

The borofluoric acid scavenger represented by the general formula (2) or (4) may be added directly to the waste water, or a packed bed may be formed and the waste water may be passed through the bed.

The hydrofluoric acid scavenger represented by the general formula (2) or (4) is quaternized by an aqueous solution or a substituent of a quaternary ammonium salt represented by the general formula (1) or (3). Can be prepared by reacting an aqueous solution of a nitrogen-containing heterocyclic compound having a nitrogen with an anionic polymer. Particularly, an anionic polymer corresponding to A in the general formula (2) or an aqueous solution thereof is used. Can be suitably used, and they can be easily obtained by mixing these and subjecting the resulting precipitate to solid-liquid separation.

The quaternary ammonium salt or the nitrogen-containing heterocyclic compound having nitrogen quaternized by a substituent and the anionic polymer can be mixed in any ratio, but preferably a quaternary ammonium salt or nitrogen-containing compound. The mole ratio of the anionic moiety is from 0.01 mol to 5.0 mol, preferably from 0.1 mol to 2.5 mol, per 1 mol of the heterocyclic compound. Thus, a highly effective scavenger can be efficiently produced.

Alginic acid may be only mannuronic acid, only gnoleronic acid, or a random form thereof, and those having a polymerization degree of about 200 to 800 are preferably used.

Pectin is a linear polysaccharide composed of D-galacturonic acid, and a part of the carboxylic acid is a methyl ester. In the present invention, High methoxypectin having a degree of esterification of 50% or less_b and low methoxypectin having a degree of esterification of 50% or less can be suitably used.

Gelatin is composed of one amino acid and imino acid linked by a peptide bond, and has various amino acid components. Glycine, proline, and hydroxyproline occupy a molecular weight of 1Z2 or more. The average molecular weight is from 200,000 to 200,000 or more, and among them, those having a molecular weight of 50,000 to 150,000 are particularly preferable.

As the aeon-modified starch, carboxymethyl starch or phosphorylated starch in which an anionic functional group is introduced into the hydroxyl group of the glucose portion of the starch, such as a carboxymethyl group or a phosphonic acid group, is preferable. Can be used for

The carboxymethyl cellulose is not particularly specified, but those having a carboxyl substitution degree of 0.5 to 2.0 per Darcos unit can be suitably used.

As polyacrylic acid, a polymer obtained by polymerizing acrylic acid and Z or a salt thereof is used. Acrylic acid can be polymerized by a persulfate such as ammonium persulfate, persulfuric acid or the like, or a redtus catalyst comprising a combination of a persulfate / reducing agent. Further, polymerization may be performed by visible light, ultraviolet light, electron beam, or γ-ray. Further, products produced by modifying a polyacrylate such as polymethyl acrylate with a caustic alkali can also be suitably used.

As the copolymer of acrylamide and acrylic acid, those obtained by copolymerizing acrylamide with sodium acrylate or a cationic monomer can be suitably used. Commercially available products are commercially available from Sanyo Chemical Industries, Ltd. under the trade name “Sunfloc® j”, and from Mitsui Cynamid Co., Ltd. under the trade name “SuperFlock®”. Commercially available products are exemplified.

The scavenger obtained by the above method is directly poured into waste water containing borofluoride adjusted to a pH of less than 5 and stirred for a while, then solid-liquid is added to the water to be treated and the discharged material. Separation makes it possible to remove borofluoride from wastewater.

Alternatively, it is also possible to remove the borofluoride salt by filling the scavenger with a removal tower and passing the wastewater containing a hydrofluoride adjusted to pH 5 or less. .

The scavenger of the general formula (2) or (4) used for removing borofluoride desorbs borofluoric acid by contact with a solution adjusted to a pH of 8 or more, and is used as a repeated scavenger. Can be used.

In the method of the present invention, borofluoride can be removed, but fluorine and boron cannot be removed. When fluorine and boron are contained in the wastewater together with borofluoride, the fluorine is removed by a common method such as calcium treatment with canosome and aluminum, and then the method of the present invention is used. May be applied.

In the case of a waste liquid containing a large amount of hydrogen borofluoride in the wastewater, a compound capable of reacting with borofluoric acid to form a salt is added before the addition of the borofluoric acid scavenger of the present invention. It can also be precipitated as chloride and removed. Compounds that form salts by reacting with borofluoric acid include potassium salts such as potassium chloride and potassium carbonate, and the addition of these salts can reduce borofluoric acid in the wastewater to some extent. By using the fluorinated acid that cannot be removed by this operation with the supplement of the present invention, the supplement can be used efficiently.

Even if the borofluoride supplement of the present invention is added in a necessary amount or more, there is no problem in the ability to remove borofluoric acid, but the COD and BOD in the wastewater increase. It can be lost. In this case, by adding a quaternary ammonium scavenger after the borofluoric acid removal treatment, the surplus borofluoride scavenger can be removed. Activated carbon, bentonite, kipro gum and the like can be mentioned as quaternary gamma-pum supplements, and COD and BOD values can be suppressed by adding them after removing borofluoric acid in wastewater.

Example

The fluorinated fluorinated scavengers of the general formulas (2) and (4) of the present invention will be described in detail in Itoda based on the following examples.

(Example 1)

As compounds represented by the general formulas (2) and (4), scavengers were prepared as follows. A quaternary ammonium salt or a nitrogen-containing heterocyclic compound having a nitrogen quaternized by a substituent is dissolved in 1,000 ml of water in an amount shown in Table 1 below, and the aeonionic polymer compound is dissolved in water. Was dissolved in 1,000 O ml of water in the amount shown in Table 1, and a precipitate formed by mixing the two aqueous solutions was collected to prepare a hydrofluoric acid scavenger.

【table 1 】

5 001984

17

Alginic acid (Kimitsu Chemical Co., Ltd. Kimitsu Arginsan)

Pectin (L M Pectin, German Helpstrite)

Gelatin (Gelatin manufactured by Nitta Gelatin Co., Ltd.)

Ayuon starch (Privine p-163, manufactured by Nippon Starch Co., Ltd.) Carboxymethylcellulose (Daiichi Kogyo Seiyaku Co., Ltd. Seguchigen) Polyacrylic acid (Aron, manufactured by Toa Gosei Co., Ltd.)

Copolymer of acrylamide and acrylic acid (RA-51 from RasaFlok Industrial Co., Ltd.)

Next, an embodiment of the processing method will be described in detail.

The analysis of fluorine in the treated water was performed by the lanthanum-arizarin complexon method specified in JisK0102, and the analysis of boron was measured by the methylene blue absorption spectrophotometry specified in jIsK0102. The wastewater used for the treatment was water containing borohydride discharged from the Metzki plant.

This waste water, fluoroboric acid salt 1 1 4 ppm; cage containing Marete ^{(l 3 X 1 0- 3 mo} 1/1. 1 4 ppm and fluorine as 1 0 0 ppm, boron), p H Was 2.8.

(Example 2)

As shown in Table 2, the compounds of the general formulas (1) and (3) were added to the wastewater at a temperature of 100 ° m 1, and the mixture was stirred for 5 minutes and then allowed to stand. At this time, the treated water was found to be cloudy, and was further filtered through a 5 A filter paper. The filtrate was analyzed for fluorine and boron. As a comparative example, the same treatment was performed without using the compound of the general formula (1). Table 2 shows the processing results.

[Table 2]

As shown in Table 2, the use of the compound of the general formula (1) or the general formula (3) makes it possible to remove fluorine and boron, that is, borofluoride, in wastewater. If the amount of the compound of the general formula (1) or (3) is equal to or more than that of the borofluoride, the compound can be removed up to about 5 pm.

(Example 3)

Trim as a compound represented by the general formula (1) After stirring Chirusuteari Ruan monitor © skeleton Lai de a 1 · 4 X 1 0 one ³ mo 1/1 added to 5 minutes, as a coalescing aid diatomaceous earth, bentonite DOO, arrows s 1 § alginic acid sodium © beam gZ1 was added, and a copolymer of acrylamide and acrylic acid (RA-51, manufactured by Rasafloc Industrial Co., Ltd.) was further added as a water-soluble polymer flocculant, and the mixture was stirred for 5 minutes and left to stand. . At this time, the sludge settling speed (the time until the supernatant liquid became clear) was visually compared. The results are shown in Table 3.

(Example 4)

Drainage 1, 0 0 as 0 ml in the general formula (1), the compound represented by the trimethyl chill stearyl ammonium Niu skeleton Rye de (in Table 3 TMS AC) 1. 4 X 1 0- 3 mo 1 Z 1, General and a compound represented by formula (3), stirred for 5 minutes cetyl two Jiumukurorai de (in Table 3 CPC) 1. 4 X 1 0- 3 mo 1/1 respectively were added, and the flocculating aid After adding 1 gZ1 of diatomaceous earth and stirring for 5 minutes, 5 ppm of iron chloride as a polyvalent metal compound and 5 ppm of cerium sulfate as a rare earth compound were added. As a water-soluble polymer coagulant, a copolymer of acrylamide and atarilic acid (RA-51, manufactured by Rasafloc Industrial Co., Ltd.) was added, and the mixture was stirred for 5 minutes and then allowed to stand. The sludge layer thickness at this time was compared. The results are shown in Table 3.

Sludge layer thickness: The thickness of the sludge 10 minutes after the completion of the treatment step was visually checked. (Thickness of sludge and height of liquid to drainage) The ratio is described.

[Table 3] General formula [1] / [3] Coagulation aid Polyvalent metal / rare earth Sedimentation velocity Sludge layer thickness Invention 2 T SAC--No sedimentation 1 Invention 10 T SAC diatomaceous earth 30 seconds 0.10 Invention 11 TMSAC bentonite 1 50 seconds 0.12 Invention 12 TMSAC sodium alginate-60 seconds 0.12 Invention 13 TMSAC diatomaceous earth chloride 20 seconds 0.06 Invention 14 TMSAC diatom cerium sulphate 20 seconds 0.05 Invention 15 CPC diatomaceous earth 35 seconds 0.11 Invention] 6 CPC bentonite One 50 seconds 0.12 Higashiki 17 CPC sodium alginate One 65 seconds 0.12 Invention 18 CPC diatomaceous earth iron chloride 25 seconds 0.05 Invention 19 CPC diatomaceous earth cerium sulfate 20 seconds 0.06

* In all of the treatment results of the present inventions 10 to 14, the fluorine concentration was 5 ppm or less and the boron concentration was 1 ppm or less. In all of the processing results in the present invention, the fluorine concentration was 5 ppm or less and the boron concentration was 1 ppm or less.

As shown in Table 3, the use of the flocculation aid quickly flocculates and precipitates the poorly soluble substance formed by the borofluoride and the compound represented by the general formula (1) or (3). It becomes possible. Further, by using a polyvalent metal Z rare earth compound in combination, it is possible to increase the sedimentation speed and reduce the amount of sludge.

(Example 5)

As a compound represented by the general formula (2), 35 g of trimethylstearylammonium-pum chloride is dissolved in 1,000 ml of water, and Kimizargin 20 is dissolved as an anionic polymer compound. g was dissolved in 1,000 ml of water, and the two aqueous solutions were mixed, and the resulting precipitate was collected to prepare borofluoric acid scavengers 1,15.

Boron hydrofluoric acid scavenger 1 was added to 1,000 ml of wastewater as shown in Table 4, and after stirring for 1 hour, solid-liquid separation was performed, and the fluorine and boron concentrations were measured. As a comparative example, the same operation was performed by adjusting the H of the waste water to 7.5 with NaOH. The results are shown in Table 4.

[Table 4] Amount of scavenger 1 Fluorine concentration after water pH treatment Boron concentration after treatment Comparative Example 2 5.0 g 1 Wastewater 1 L 7.0 97.5 ppm 13.8 ppm Comparative Example 3 10-Og 1 Wastewater 1 L 7.0 97.8 ppm 14.0 ppm Comparative Example 4 20.0 g / drain 1 7.0 99.0 ppm 13.8 ppm Comparative 5 5.0 g 1 drain 1 L 5.0 98.0 ppm 13.0 ppm Comparative 6 lO.Og / drain 1 L 5.0 97.5 ppm 14.0 ppm Comparative 7 20.0 g 1 drain 1 L 5.0 97.0 ppm 13.6 ppm Example 20 2.5 g 1 Wastewater 1 L 2.8 35.0 ppm 5.0 ppm Example 21 5.0 g 1 Wastewater 1 L 2.8 9.2 ppm 0.8 ppm Example 22 l O.Og / Wastewater 1 L 2.8 1.5 ppm 0.1 ppm Treated water as shown in Table 4 : If the pH is 5 or more, borofluoride cannot be removed, but if the pH is less than 5, use the scavenger to remove borofluoride be able to.

Similarly, the treatment of effluent from the sapphire factory was carried out using other scavengers 2 to 14. The pH of the wastewater from the Metsuki Plant was 2.8, and the amount of trapping agent used was all 10 g. The wastewater was treated as 11 and the fluorine and boron concentrations were measured. Table 5 shows the results.

[Table 5]

Fluorine concentration after treatment Boron concentration after treatment Example 23 Scavenger 2 2.0 ppm 0.2 ppm

Example 24 Scavenger 3 1.8 ppm 0.2 ppm

Example 25 Scavenger 4 1.6 ppm 0.1 ppm

Example 26 Scavenger 5 2.1 ppm 0.2 ppm

Example 27 Capture agent 6 l.o ppm 0.1 ppm

Example 28 Scavenger 7 1.6 ppm 0.1 pm

Example 29 Scavenger 8 2.2 ppm 0.3 ppm

Example 30 Scavenger 9 1.5 ppm 0.2 ppm

Example 31 Scavenger 10 1.4 ppm 0.3 ppm

Example 32 Scavenger 11 2.1 ppm 0.1 pm

Example 33 Scavenger 12 1.3 ppm 0.3 ppm

Example 34 Scavenger 13 1.8 ppm 0.2 ppm

Example 35 Scavenger 14 1.5 ppm 0.2 ppm

Example 36 Scavenger 15 2.5 ppm 0.3 ppm

Example 37 Capture agent 16 1.4 ppm 0.3 ppm

Example 38 Scavenger 17 1.4 ppm 0.1 ppm

Example 39 Scavenger 18 2.3 ppm 0.1 ppm

Example 40 Scavenger 19 1.5 ppm 0.3 ppm

Example 41 Scavenger 20 1.6 ppm 0.2 ppm

Example 42 Scavenger 21 2.0 ppm 0.3 ppm As shown in Table 5, all scavengers can remove borofluoride.

(Example 6)

500 g of borofluoric acid scavenger 1 was filled in a filling tank, and water of 1,000 m 1 per minute was passed therethrough. The fluorine concentration and the boron concentration of the treated water obtained each time the treatment was performed were measured. Table 6 shows the results. [Table 6] Wastewater flow rate Fluorine concentration Boron concentration after treatment

100L 2.2 ppm 0.2 ppm

200L 2.5 ppm 0.3 ppm

300L 3,8 ρρτη 0.3 ppm

400L 4.2 ppm 0.5 ppm

500L 4.8 ppm 0.6 ppm

600L 6.8 ppm 1.1 ppm

700L 16.0 ppm 2,0 ppm As shown in Table 6, the water can be passed through the borofluoric acid scavenger to remove borofluoride. However, when the amount of treated water exceeds a certain value, the removal rate decreases.

Next, a method for regenerating the borofluoric acid scavenger will be described in detail. (Example 7)

After treating the wastewater of 7001 in Example 6, the filling tank was filled with a NaHO solution adjusted to pH10. After 30 minutes, the NaOH solution was discarded, washed with water and regenerated. The wastewater was treated according to Example 5 again using this filling tank. Table 7 shows the results.

[Table 7]

As shown in Table 7, the borofluoric acid scavenger once used to remove the borofluoride was reused by treating it in an alkaline solution. It became possible to do.

(Example 8)

After adding 100 ml of waste water containing 100 g / L of borofluoride as fluorine and reacting with 100 ml of fluorinated water, the liquid obtained by removing the precipitate deposited as borofluoridium has the general formula ( 1) Trimethyl stearylammonium chloride is added as the compound represented by (1), and cetyl pyridium chloride is added as the compound represented by the general formula (3), and the mixture is stirred for 5 minutes. Diatomaceous earth 1 g / L as coagulant Aid B, stirred for 5 minutes, then copolymerized with acrylamide and acrylic acid as water-soluble polymer coagulant (RasaFlok Industries, Ltd.) RA-51) manufactured by Co., Ltd. was added, and the mixture was stirred for 5 minutes and then allowed to stand. As a result of measuring the fluorine concentration in the supernatant, the fluorine content was less than 8 ppm. Table 8 shows the results.

[Table 8]

As shown in Table 8, in the case of a waste liquid containing a large amount of borofluoride, it is necessary to add a large amount of a hydrofluoric acid scavenger in the present inventions 43 and 46. Since it can be removed to some extent with potassium chloride, a small amount of borofluoric acid scavenger was able to achieve a sufficient removal effect.

(Example 9)

Trimethylene is added to 100 mL of wastewater as a compound represented by the general formula (1). 1 Le stearyl § emissions monitor © Solid opening line de. 4 X 1 0 one ³ mo 1 ZL added to 5 minutes stirring, after as a coalescing aid stirring kieselguhr 1 g / L added to 5 minutes, water A copolymer of acrylamide and acrylic acid (RA-51, manufactured by RasaFlok Industries Co., Ltd.) was added as a conductive polymer flocculant, and the mixture was stirred for 5 minutes, and then subjected to solid-liquid separation. Activated carbon, bentonite, and kipro gum were added to the filtrate as quaternary ammonium scavengers, and after stirring for 5 minutes, the COD of the solid-liquid separated liquid was compared. Table 9 shows the results.

[Table 9]

As shown in Table 9, if the borofluoric acid scavenger becomes excessive, the COD after drainage increases, but the addition of the quaternary ammonium scavenger results in an excess of borofluoric acid. The acid scavenger could be removed. Industrial applicability

As described above, the additive used in the method for treating effluent containing borofluoride according to the present invention and the method for treating the effluent contain external energy such as heating from the effluent containing borofluoride. This is useful because fluorine and boron can be removed in a short time with a small amount of sludge without using it. In addition, facilities such as installing tanks for secondary processing (advanced processing) This is useful because it does not need to be increased and advanced treatment can be performed only with the existing primary treatment equipment.

Claims

The scope of the claims

1. An additive for removing borofluoric acid from wastewater, comprising at least one compound represented by the following general formulas (1) to (4).

General formula (1)

R i to R ₄ each independently represent an alkyl group having 1 to 24 carbon atoms, an alkyl group, a phenyl group or a benzyl group, and R i to R ₄ may be linked to each other to form a ring; . X represents an anion.

General formula (2)

R ₄ to R ₄ each independently represent an alkyl group, alkenyl group, phenyl group or benzyl group having 1 to 24 carbon atoms, and R ₄ to R ₄ may be linked to each other to form a ring. A represents an anionic polymer.

General formula (3) ^ ノ

C '

R i represents an anoalkyl group having 1 to 24 carbon atoms, an alkenyl group, a phenyl group or a benzyl group. Z represents an atomic group necessary for constituting a hetero ring. X represents an anion.

General formula (4)

Ri ""- ⁺ NZ

A

R i represents an alkyl group having 1 to 24 carbon atoms, an alkyl group, a phenylazole group or a benzyl group. Z represents an atomic group necessary for constituting a hetero ring. A represents an aeon polymer.

2. —A compound of the formula (2) and formula (4), wherein A of the borofluoric acid trapping complex IJ has a structure selected from the following group A:

2. The borofluoric acid scavenger according to 1.

Group A: Alginate, pectin, gelatin, anionized starch, carboxymethylcellulose, polyacrylic acid, copolymer of acrylic acid and acrylic acid

3. The method according to claim 2, wherein the number of moles of the anionic polymer site is 0.01 to 5.0 moles per mole of the quaternary ammonium salt. Borofluoric acid scavenger.

4. Regarding a wastewater treatment method for removing borofluoric acid from wastewater containing borofluoride, the following general formula (1) or general formula (3) is added to the wastewater. A wastewater treatment method comprising adding at least one kind of a borofluoric acid scavenger represented by the formula:

General formula (1)

R i to R ₄ each independently represent an alkyl group, alkenyl group, phenyl group or benzyl group having 1 to 24 carbon atoms, and R i to R ₄ may be linked to each other to form a ring; . X— represents an anion.

General formula (3) z,

C ′ Ri represents an alkyl group having 1 to 24 carbon atoms, an alkyl group, a fuel group or a benzyl group. Z represents an atomic group necessary for constituting a hetero ring.

X- represents an anion.

5. A method comprising adding 0.1 to 0.5 mol of a borofluoric acid scavenger represented by the following general formula (1) per 1 mol of borofluoric acid ions contained in wastewater. Item 4. The wastewater treatment method according to Item 4.

General formula (1)

R to R ₄ each independently represent an alkyl group having 1 to 24 carbon atoms, a alkenyl group, a phenyl group or a benzyl group, and Ri to R ₄ may be linked to each other to form a ring. X represents an anion.

6. After adding at least one of the borofluoric acid scavengers represented by the general formula (1) or (3), diatomaceous earth, bentonite, kaolin, activated carbon, portland cement, high hydrophilicity, etc. The wastewater treatment method according to claim 4, wherein one or more compounds selected from a molecular compound, a polyvalent metal, and a rare earth compound are added.

7. The amount of the compound to be added is 0.0005 to 5.0% by weight of the water to be treated. /. The wastewater treatment method according to claim 6, wherein:

8. Wastewater treatment characterized by contacting wastewater containing borofluoride with a borofluoric acid scavenger represented by the general formula (2) or (4) at a pH of less than 5. Method.

General formula (2)

R to R ₄ each independently represent an alkyl group, alkenyl group, phenyl group or benzyl group having 1 to 24 carbon atoms, and R to R ₄ may be linked to each other to form a ring. A represents an ayuonic polymer selected from Group A below.

Group A: Alginic acid, pectin, gelatin, anionized starch, carboxymethyl senorellose, polyatalinoleic acid, copolymer of atalinoleamide and atalinoleic acid

General formula (4) Ri—NZA

No

R i represents an alkyl group having 1 to 24 carbon atoms, an alkyl group, a fuel group or a benzyl group. Z represents an atomic group necessary for constituting a hetero ring.

Haa RRNII

A represents a union polymer.

9. Regarding the method for regenerating the borofluoric acid capturing agent represented by the following general formula (2) or (4), use a capturing agent that captures borofluoric acid! A method for regenerating a hydrofluoric acid scavenger, comprising regenerating by contacting with an aqueous solution adjusted to H 8 or more.

General formula (2)

one

1 ₁ to 1 ₄ are each independently of the number 1-2 4 alkyl carbon, Aruke - group, represents a phenyl group or a benzyl group, the ring may form a form a linked R i R each other. A represents an ionic polymer.

General formula (4)

R represents an alkyl group having 1 to 24 carbon atoms, an alkenyl group, a phenyl group or a benzyl group. z represents an atomic group necessary for constituting a hetero ring. A represents an aionic polymer.

The use of conventional equipment for the treatment of wastewater containing borofluoride discharged by metalworkers, glass processors, print substrate processors, etc. makes it extremely easy and efficient to generate sludge. So that processing can be performed at room temperature in a short time.

Means for solving the problem is a borofluoric acid scavenger represented by the following general formula (1) or (2).

General formula (1)

R group to form a Hue ring

One

R i to R ₄ each independently represent an alkyl group, alkenyl group, phenyl group or benzyl group having 1 to 24 carbon atoms, and R i to R ₄ may be linked to each other to form a ring. A represents an anionic polymer.