JPH0686998A - Method for removing phenols and anilines in water - Google Patents

Abstract

PURPOSE:To make it possible to remove phenols and anilines by adding a cationic flocculant having an amine group and a phenol oxidation enzyme together, although the activity of enzyme is lost due to the bonding of an oxidation product with enzyme and the oxidation product remains unremoved, in a treatment of phenols and anilines in water using phenol oxidation enzyme. CONSTITUTION:Water containing phenols and/or anilines is treated by adding cationic flocculant having an amino group and a phenol oxidation enzyme together. Consequently, an oxidation product generated by catalytic oxidation of phenol oxidation enzyme is allowed to react with the cationic flocculant having an amino group very easily. Therefore, it is possible to oxidize phenols and anilines with the concurrent prevention of enzyme from losing its activity by bonding of the oxidation product with the cationic flocculant having an amino group, and at the same time, remove the oxidation product easily by flocculation.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for removing phenols and anilines in water, wherein a phenol oxidase and a cationic flocculant having an amino group are used in combination and the enzyme is coagulated by the flocculating agent. While preventing the inactivation of the, while carrying out the oxidation by the catalytic action of phenol oxidase, by aggregating and removing the oxidation product by the aggregating agent, clean water treatment, industrial water treatment, wastewater treatment, Used for waste leachate treatment.

[0002]

2. Description of the Related Art Wastewater from synthetic organic chemical plants, coke plants, etc. contains various phenols and anilines. The treatment of these wastewaters has hitherto been carried out by an adsorption method and an extraction method. , Ion exchange method, oxidation method, biological treatment method, etc. have been studied, but only biological treatment method (activated sludge method) is practically used. However, even in this biological treatment method,
Since these compounds have low biodegradability and are toxic, their biological activity is inhibited and treatment is not carried out sufficiently, and therefore many of them are released into the environment without being biodegraded. Therefore, development of an inexpensive and simple treatment method for these compounds is expected.

An inexpensive and simple treatment method for phenols and anilines is a treatment method utilizing the catalytic action of an enzyme. There have been some attempts to utilize phenol oxidase, but this has two important drawbacks. That is, the phenol oxidase is inactivated by binding with the oxidation products of phenols and anilines, and the oxidation products of phenols and anilines remain dissolved in water. It is not removed.

[0004]

The conventional treatments using phenol oxidase have the above-mentioned important drawbacks. The problem to be solved by the present invention is to completely remove the oxidation products of phenols and anilines and prevent the inactivation of phenol oxidase.

[0005]

The present inventor has found that the oxidation products of phenols and anilines can easily bind to a cationic flocculant having an amino group. Therefore, it is considered that when phenol oxidase and a cationic flocculant having an amino group are used in combination, the inactivation of the enzyme can be prevented and the oxidation product can be easily flocculated and removed. In the present invention, a phenol oxidase and a cationic flocculant having an amino group are used in combination, and the phenols and / or anilines are treated with phenol while preventing the enzyme from being deactivated by the flocculant. It is a method of oxidizing with a oxidase and aggregating and removing the oxidation product with the aggregating agent.

In the present invention, the phenols are phenol, chlorophenol, methoxyphenol and cresol.
And phenol substituted products such as hydroxyphenol and anilines, aniline and p-chloroaniline, 3,
An aniline-substituted product such as 4-dichloroaniline.

In the present invention, the phenol oxidase means tyrosinase, laccase, peroxidase, polyphenol oxidase and the like. Tyrosinase and lacquer
In the presence of oxygen (good in air), peroxida
Ze and the like catalyze the oxidation of phenols and anilines in the presence of hydrogen peroxide. Tyrosinase may be a commercially available purified enzyme, or may be a sample derived from animals, plants, or microorganisms containing this enzyme such as mashroom. The laccase may be a commercially available enzyme, and animals, plants,
A sample derived from a microorganism may be used. Peroxidase may be a commercially available enzyme, such as horseradish, animals containing this enzyme,
Samples derived from plants or microorganisms may be used.

In the present invention, the amino group includes a substituted amino group. As the cationic flocculant having an amino group, amine-epichlorohydrin polycondensate, polyalkylene polyamine, polyacrylic acid aminoethyl ester, polymethacrylic acid aminoethyl ester, polyacrylamide cation modified product, chitosan, etc. included.

The condition of the enzyme-catalyzed oxidation reaction is that the reaction temperature is 1
The optimum temperature is 0 to 50 ° C and 10 to 30 ° C.
And pH 6-8 is optimal. The amount of coagulant added is
The concentration of phenols and anilines is related to the concentration of phenols and anilines, and is determined by a preliminary test in advance. The phenol oxidase is preferably added after being dissolved in a buffer solution at a concentration of 1 mg / ml or more. In addition,
The luoxidase may be used after being immobilized on a carrier.

In the case of phenols and anilines which are difficult to be oxidized by phenol oxidase, an auxiliary agent is added to accelerate the reaction so that the oxides can be separated from the phenols and anilines. Polymerization may be performed. The auxiliary agent added depends on the enzyme. For example, in the case of tyrosinase (origin from mashleum) and peroxidase (origin from horseradish), phenol and the like are added, and in the case of laccase (origin from blast fungus), o-methoxyphenol and the like. Is added.

In the case of tyrosinase and laccase, the oxidation reaction requires oxygen, so it is preferable to stir in air or aerate oxygen or air. In the case of peroxidase, the addition of hydrogen peroxide is necessary. Also,
These oxygen and hydrogen peroxide may be generated by a chemical reaction or the like.

The coagulant may be added from the beginning or may be added during or after the oxidation by the phenol oxidase. In the case of tyrosinase and laccase, the inactivation is slow, and thus the coagulant may be added during or after the oxidation. In the case of peroxidase, the enzyme specifically binds to the oxides of phenols immediately and inactivates, so it is better to add a cationic coagulant having an amino group from the beginning to prevent it. .

The agglomerated oxidation product may be removed by precipitation, or may be removed by a method such as filtration, centrifugation or flotation.

[0014]

The phenol oxidase catalyzes the oxidation of phenols and anilines to produce oxidation products. The phenol oxidases are inactivated by binding with these oxidation products. Also, their oxidation products remain dissolved in water and are not removed. The present invention takes advantage of the fact that the oxidation products of phenols and anilines have a property of easily binding to a cationic flocculant having an amino group, and the following actions are performed. When the phenol oxidase and the cationic flocculant having an amino group are used in combination, the oxidation product is easily bound to the flocculant, so that the enzyme is not inactivated. Further, the oxidation product is one that is easily combined with the aggregating agent and aggregates to be completely removed.

[0015]

Example 1 Phenol 0.5 mM, tyrosinase (S
A reaction solution containing 20 U (enzyme unit) / ml (manufactured by IGMA, origin of mushroom) and 5 mM phosphate buffer (pH 7.0) was stirred in the air at room temperature. After 30 minutes, the removal rate of phenols was 100%, and a brown solution was obtained, but no precipitation occurred. When 20 mg / l of a hexamethylenediamine-epichlorohydrin polycondensate or a polyethyleneimine commercial product was added to this solution and stirred, each coagulated, and the supernatant liquid became a colorless and transparent liquid.

On the other hand, a commercially available nonionic flocculant polyacrylamide was added to the above reaction solution which had been oxidized with tyrosinase.
0, 50 and 100 mg / l were added, but no aggregation effect was observed.

Phenol 0.5 mM, tyrosinase 20
U / ml, phosphate buffer 5 mM (pH 7.0) and hexamethylenediamine-epichlorohydrin polycondensate 2
The reaction containing 0 mg / l was stirred at room temperature. Two
The phenol removal rate after 0 minutes was 100%, brown flocs were formed and precipitated, and the supernatant became a colorless and transparent liquid.

Further, only the coagulant hexamethylenediamine-epichlorohydrin polycondensate was added to a 0.5 mM aqueous solution of phenol for 10, 20, 40, 80, 200 and 400.
Even if mg / l was added, no aggregation effect was observed. That is, the phenol itself could not be aggregated by the aggregating agent, but it was transformed into a form capable of aggregating by oxidizing the phenol with tyrosinase.

The hexamethylenediamine-epichlorohydrin polycondensate was synthesized by the following method. Take 20 g of hexamethylenediamine, add 40 g of water, and slowly add 15.9 g of an equimolar amount of epichlorohydrin,
After stirring at 45 ° C for 50 minutes, dilute 2 times with water,
The mixture was stirred at 45 ° C for 20 minutes. The pH of the obtained polycondensate was adjusted to 4 with hydrochloric acid, and the concentration was diluted to 5%. The relative viscosity of the 1% concentration solution of this polycondensate to water at 20 ° C. is 4.8.

[0020]

Example 2 p-chlorophenol, p-methoxyphenol, m-cresol, p-cresol or catechol 0.5 mM, tyrosinase 20 U / ml and phosphate buffer 5 mM ( Each of the 5 reaction solutions containing pH 7.0) was stirred in air at room temperature. The removal rate of phenols after 30 minutes was 100% in all, and a brown solution was obtained, but no precipitation occurred. When 20 mg / l of a hexamethylenediamine-epichlorohydrin polycondensate or a polyethyleneimine commercial product was added to this solution and stirred, each coagulated, and the supernatant liquid became a colorless and transparent liquid.

[0021]

Example 3 o-chlorophenol, m-chlorophenol, o-methoxyphenol, m-methoxyphenol
Of the reaction liquid containing 0.5 mM of ole, o-cresol, resorcin or hydroquinone, 100 U / ml of tyrosinase, 1.5 mM of phenol, and 5 mM of phosphate buffer (pH 7.0) in air. Stirred at room temperature in. The removal rate of phenols after 1 hour is 10
0% gave a brown solution but no precipitation. When 40 to 60 mg / l of hexamethylenediamine-epichlorohydrin polycondensate was added to each of these solutions and stirred, each coagulated and the supernatant became a colorless and transparent liquid. Thus, even for phenols which are difficult to oxidize by themselves, they are polymerized with the phenol oxide by adding phenol as an auxiliary agent, and agglomerate them with a cationic flocculant having an amino group. Can be removed.

[0022]

Example 4 Aniline, p-chloroaniline and 3,4
-The anilines of dichloroaniline cannot also be oxidized by tyrosinase by themselves, but by adding phenol as an auxiliary agent to polymerize with phenol oxide,
These can be coagulated and removed by a cationic coagulant having an amino group. 0.5m of these anilines
M, tyrosinase 50U / ml, phenol 0.5m
The three reaction solutions containing M and 5 mM phosphate buffer (pH 7.0) were each stirred in air at room temperature. The removal rate of anilines after 1 hour was 100% in all, and a brown solution was obtained, but no precipitation occurred. Hexamethylenediamine-epichlorohydrin polycondensate 20-
When 30 mg / l was added and the mixture was stirred, all were aggregated, and the supernatant became a colorless and transparent liquid.

[0023]

Example 5 0.5 mM of o-methoxyphenol or catechol, 100 U / ml of laccase (manufactured by SIGMA, origin of blast fungus) and 5 mM of phosphate buffer (pH)
The two reaction solutions containing 6.5) were each stirred in air at room temperature. The removal rate of phenols after 1 hour was 100% in all, and a brown solution was obtained, but no precipitation occurred. When 20 mg / l of hexamethylenediamine-epichlorohydrin polycondensate was added to this solution and stirred, both were aggregated and the supernatant became a colorless and transparent liquid.

[0024]

Example 6 Aniline, p-chloroaniline and 3,4
-The anilines of dichloroaniline cannot be catalytically oxidized by the above-mentioned laccase by themselves, but they are polymerized with this oxide by adding o-methoxyphenol as an auxiliary agent, and cationic aggregation having an amino group is carried out. It can be coagulated and removed by the agent. 0.5m of these anilines
M, laccase 100 U / ml, o-methoxypheno-
1.0 mM and phosphate buffer 5 mM (pH 6.5)
Each of the three reaction solutions containing was stirred at room temperature in air. The removal rate of aniline and phenol after 1 hour was 100%, and a brown solution was obtained, but no precipitation occurred. When 20 to 30 mg / l of hexamethylenediamine-epichlorohydrin polycondensate was added and stirred to these solutions, all were aggregated, and the supernatant liquid became a colorless and transparent liquid.

[0025]

[Example 7] Phenol 0.5 mM, hydrogen peroxide 0.5
mM, peroxidase (manufactured by Wako Pure Chemical Industries, origin of horseradish) 1 U / ml and phosphate buffer 5 mM (pH 7.
The reaction solution containing 0) was stirred at room temperature. The phenol removal rate after 10 minutes was 100%, and a brown solution was obtained, but no precipitation occurred. Hexamethylenediamine-
When 20 mg / l of epichlorohydrin polycondensate was added and stirred, the mixture agglomerated and the supernatant became a colorless and transparent liquid.

[0026]

Example 8 Phenol 5 mM, hydrogen peroxide 5 mM, peroxidase (Wako Pure Chemical Industries, Ltd., horseradish origin) 2 U /
ml, phosphate buffer 5 mM (pH 7.0) and hexamethylenediamine-epichlorohydrin polycondensate 100
The reaction containing mg / l was stirred at room temperature. The phenol removal rate after 1 hour was 100%, brown flocs were produced and precipitated, and the supernatant became a colorless and transparent liquid. When the flocculant was not added, the phenol removal rate after 1 hour was 29.4%, which was a brown solution, and remained the same removal rate over time. That is, it indicates that the enzyme is rapidly deactivated unless a coagulant is added.

[0027]

[Example 9] Aniline 0.5 mM, hydrogen peroxide 0.5 m
M, peroxidase 2U / ml and phosphate buffer 5m
The reaction containing M (pH 7.0) was stirred at room temperature. The aniline removal rate after 1 hour was 100%, and a brown solution was obtained, but no precipitation occurred. 1.5 mg of hexamethylenediamine-epichlorohydrin polycondensate in this solution
When 1 was added and stirred, the mixture agglomerated and the supernatant became a colorless and transparent liquid.

[0028]

Example 10 Although 3,4-dichloroaniline cannot be catalytically oxidized by peroxidase by itself, it is polymerized with phenol oxide by adding phenol as an auxiliary agent, and this is converted into an amino group. It can be removed by aggregation with the cationic aggregating agent. A reaction liquid containing 0.5 mM of 3,4-dichloroaniline, 0.5 mM of hydrogen peroxide, 1 U / ml of peroxidase, 0.5 mM of phenol, and 5 mM of phosphate buffer (pH 7.0) at room temperature. I stirred it. The removal rate of 3,4-dichloroaniline after 1 hour was 100%, and a brown solution was obtained, but no precipitation occurred. Hexamethylenediamine-epichlorohydrin polycondensate (1 mg / l) was added to this solution and stirred.

[0029]

As described above, the oxidation product produced by the catalytic oxidation of phenols and anilines with phenol oxidase reacts very easily with the cationic flocculant having an amino group. . Therefore, the phenol oxidase and the cationic flocculant having an amino group are used in combination to oxidize the phenols and anilines in water while preventing the inactivation of the phenol oxidase, and to produce the product. It can aggregate and be completely removed. Further, since the oxidation product and the amino group react extremely easily, a small amount of the aggregating agent is sufficient.

Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location C02F 1/72 Z 9045-4D

Claims (1)

[Claims] 1. A method for removing phenols and / or anilines in water, wherein water containing phenols and / or anilines is treated with phenol oxidase and an amino group-containing positive group. The above-mentioned removal method, which comprises treating with an ionic flocculant in combination.