JP2893208B2 - Decomposition method of wastewater containing triorganotin compound - Google Patents

Description

The present invention relates to a method for effectively decomposing triorganotin compounds contained in wastewater.

[Conventional technology]

Conventionally, triorganotin compounds have been widely used in the fields of agrochemicals, marine antifouling agents, industrial germicides, etc. by utilizing their biological activities. Since it is difficult to decompose, there is concern that it will remain in the environment. For example, tributyltin compounds are widely used in antifouling paints for ship bottoms.In the case of repainting, the paints are washed with high-pressure water and then repainted, but the wastewater at this time contains tributyltin compounds. Because
Some processing is required.

In general, in a process of producing a triorganotin compound, a large amount of product water (for example, a treatment with an alkaline water, a treatment with an acid aqueous solution, or a washing step) is used, so that wastewater containing the triorganotin compound is generated.

However, in general, treatment with activated sludge is not an effective method because the decomposition of a triorganotin compound by a microorganism (for example, JP-A-1-258798) requires a long time. At present there are few examples.

[Problems to be solved by the invention]

An object of the present invention is to provide a method for rapidly decomposing a triorganotin compound contained in wastewater and preventing its accumulation as described above.

[Means for solving the problem]

The present invention relates to the compound represented by the general formula (A) or (B): [Wherein R represents an alkyl group, a phenyl group or a cycloalkyl group having 1 to 8 carbon atoms, X is a fluorine atom, a chlorine atom, a hydroxyl group, or a ^{group: -OOCR 1, -SR 2, -} ▲ SSCNR 3 2 ▼
(Wherein R ¹ and R ² represent an alkyl group or an aryl group having 1 to 12 carbon atoms, and R ³ represents an alkyl group having 1 to 4 carbon atoms), and Y represents an oxygen atom, a sulfur atom, or a group: -OOCCH = CH-COO-, Wherein the wastewater containing a triorganotin compound is electrolyzed in the presence of an alkali chloride.

Examples of the compound represented by the general formula (A) or (B) used in the present invention include trimethyltin chloride, trimethyltin oxide, bis (trimethyltin) oxide, tributyltin chloride, tributyltin fluoride, tributyltin methacrylate, and tributyltin. acetate,
Tributyltin rosinate, bis (tributyltin) fumarate, tributyltin 2,3-dibromosuccinate, triphenyltin fluoride, triphenyltin chloride,
Examples include triphenyltin acetate, triphenyltin hydroxide, and triphenyltin N, N-dimethyldithiocarbamate.

The electrolytic cell itself used in the present invention may be a known one,
As the anode, an electrode in which a valve metal such as titanium, tantalum, zirconium or the like is coated with a platinum group metal or an oxide thereof, or lead dioxide or the like is suitable. The cathode is iron,
Nickel, stainless steel, or nickel or stainless steel plated with nickel is used.

An embodiment of the present invention will be described with reference to the drawings.
The figure shows a batch type electrolytic cell, in which an anode (2) and a cathode (3) are provided in an electrolytic cell (1), and waste water containing a triorganotin compound is introduced from a pipe (4). The alkali chloride required for this electrolysis may be added to the wastewater in advance, or may be added directly to the electrolytic cell (1). If the drainage contains an alkali chloride, electrolysis may be performed as it is.
The concentration of alkali chloride in the wastewater to be electrolyzed may be 0.5 g / or more, and the pH is adjusted to 3.0 or less. As the alkali chloride, sodium chloride and potassium chloride are preferable. The triorganotin compound is decomposed by passing a direct current between the anode (2) and the cathode (3). The current at this time was 0.1 to 5 A per treated water volume, and the anode current density was 0.5 to 20 A / dm ²
The degree is preferred. The electrolysis time is about 30 to 60 minutes, and the waste water after the electrolysis is discharged from the pipe (5). (6) is an electrolytic solution stirrer, and (7) is its motor.

FIG. 2 shows a continuous type electrolytic cell in which a plurality of anodes (2 ') and cathodes (3') are alternately provided in the electrolytic cell (1 '), and a tube is provided from one end of the electrolytic cell (1'). The wastewater containing the triorganotin compound is continuously introduced by (4 '), and a direct current is passed between the anode (2') and the cathode (3 '). And discharged from the other end pipe (5 '). In this case, the flow rate is 0.
5 to 5 / nr · dm ² and the anode current density is 0.5 to 20 A /
dm ² is preferable. The alkali chloride concentration and pH of the wastewater to be electrolyzed are the same as described above.

[Action]

In the method of the present invention, wastewater containing a triorganotin compound is introduced into an electrolytic cell, and electrolysis is performed in the presence of alkali chloride, whereby the oxidizing action of nascent oxygen and chlorine generated at the anode or the generation of hydrogen at the cathode In this process, the Sn—C bond of the triorganotin compound is cleaved by the oxidizing action of hypochlorite ion generated by the reaction of the generated hydroxyl ion with chlorine generated at the anode, thereby performing a decomposition treatment.

〔Example〕

 Hereinafter, the effects of the present invention will be described with reference to examples.

Example 1 Tributyltin chloride contained in wastewater was decomposed by the electrolytic cell shown in FIG. Diameter for electrolytic cell
An electrode made of lead oxide having a width of 2 cm and a length of 5 cm was attached as an anode and a stainless steel (SUS304) electrode of the same size as a cathode was attached to a polyethylene container having a size of 12 cm, a height of 18 cm and a capacity of 2. Drain in the electrolytic cell (Tributyltin chloride 52mg /, NaCl18
0g /, pH2) 1 was supplied and a current of 0.6 A was applied. The distance between the electrodes was about 5 mm, and the liquid temperature was 21 ° C. After electrolysis for 30 minutes, the treated water was acidified with hydrochloric acid, the organic tin compound was extracted with cyclohexane, and after passing, tributyltin chloride was analyzed by gas chromatography. As a result, it was 0.14 μg / g.

Examples 2 to 11 Wastewater containing various triorganotin compounds shown in Table 1 was treated in the same manner as in Example 1, and analyzed by gas chromatography as the respective triorganotin chloride. The results are converted into the respective triorganotin compounds and are also shown in Table 1.

Example 12 Tributyltin chloride contained in wastewater was decomposed by the electrolytic cell shown in FIG. Length as an electrolytic cell
20cm, width 7cm, height 8cm using polyethylene,
In the longitudinal direction, a platinum-plated titanium electrode having a width of 4 cm and a length of 5 cm as an anode and nickel electrodes having the same size as a cathode were alternately arranged three by three. Waste water from one end of this electrolytic cell (tributyltin chloride 86mg /, NaCl60g /
, pH 1.5) at a flow rate of 1 / hr and a total current of 6 A. The concentration of tributyltin chloride in the waste water after the electrolytic treatment was analyzed in the same manner as in Example 1 and the result was 0.12 to 0.24 μg /
Met.

〔The invention's effect〕

According to the method of the present invention, it is possible to quickly and efficiently decompose highly toxic triorganotin compounds by electrolyzing wastewater containing triorganotin compounds with a small amount of electricity using an electrolytic cell having a simple structure. Since it can be used, it is industrially useful.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing one example of an electrolytic cell used in the method of the present invention, and FIG. 2 is a schematic sectional view showing another example. (1), (1 ') ... electrolytic cell, (2), (2') ... anode, (3), (3 ') ... cathode.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kan Tokunaga 12-20 Takagaki-cho, Takatsuki-shi, Osaka (56) References JP-A-4-66187 (JP, A) JP-A-1-288391 (JP, A) JP-A-60-209299 (JP, A) JP-A-51-45628 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C02F 1/46-1/48

Claims (2)

(57) [Claims] 1. A compound of the general formula (A) or (B) [Wherein R represents an alkyl group having 1 to 8 carbon atoms, a phenyl group or a cycloalkyl group, X represents a fluorine atom, a chlorine atom,
Hydroxyl, or a ^{group: -OOCR 1, -SR 2, -} ▲ SSCNR 3 2 ▼ ( wherein R
¹ and R ² represent an alkyl group or an aryl group having 1 to 12 carbon atoms, and R ³ represents an alkyl group having 1 to 4 carbon atoms);
Is an oxygen atom, a sulfur atom, or a group: -OOCCH = CH-COO-, Wherein the wastewater containing the triorganotin compound is electrolyzed in the presence of an alkali chloride. 2. The method according to claim 1, wherein the pH of the waste water at the time of performing the electrolysis is adjusted to 3.0 or less, and the concentration of alkali chloride is adjusted to 0.5 g / or more.