JPS58210892A - Treating agent of waste water containing cyan and/or thiocyan - Google Patents

Abstract

PURPOSE:To obtain a treating agent for waste water contg. cyan and thiocyan which has stability and excellent treatment efficiency by containing a reducing material that can reduce a Fehling's soln. to a cuprous halide soln. CONSTITUTION:A cuprous halide soln. which is a 1wt%- satd. soln. of cuprous halide using aq. hydrogen chloride soln. aq. alkali metal halide soln. and ethanol as a solvent is prepd. A reducing material that can reduce a Fehling's soln. is contained in said soln. at >=0.02equiv. per 1l said soln. The reducing materials used are 1 or >=2 kinds among sulfurous acid and a salt thereof, pyrosulfite, dithionite, hypophosphorous acid and a salt thereof, phosphorous acid and a salt thereof, stannous chloride, phosphines, hydrazines, hydroxylamines, hydroquinones, catechols, o-aminophenols, or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a treatment agent for wastewater containing cyanide and/or thiocyanide. More specifically, the present invention relates to a cyanide and/or thiocyanide-containing wastewater treatment agent that has an excellent ability to remove cyanide and thiocyanate from wastewater and has stable quality.

A cuprous halide solution has an excellent ability to remove cyanide and thiocyanate from wastewater, and can be used as a wastewater treatment agent for removing these components. Generally, when cyanide is converted into an insoluble substance and precipitated, if thiocyanate coexists in the wastewater, the solubility of the insoluble substance in the wastewater tends to increase, making it difficult to remove the cyanide. Cuprous oxide solutions exhibit particularly excellent performance as a treatment agent for such wastewater. However, when removing cyanide and thiocyanate from wastewater using a cuprous halide solution, there are large variations in the residual cyanide and thiocyanate concentrations in the wastewater after treatment, and the performance of the cuprous halide solution The disadvantage is that it is not stable.

As a result of intensive research in order to improve these drawbacks, the present inventors have determined the amount of dissolved oxygen in the solvent used to prepare the cuprous halide solution and the conditions under which the cuprous halide solution is exposed to air. We discovered that differences and elapsed time affect the performance of cuprous halide solutions, and after further research, we found that in order to prevent such effects and maintain stable performance, it is important to use cuprous halide solutions. , it is only necessary to add a reducing substance that can reduce Fehling's solution, and the cuprous halide solution to which such a reducing substance is added not only has stable performance, but also reduces the We discovered that the residual cyanide concentration can be significantly reduced.
We have arrived at the present invention.

Thus, according to the present invention, there is provided a cyanide and/or thiocyanide-containing wastewater treatment agent with improved stability and treatment efficiency, which comprises a cuprous halide solution containing a reducing substance capable of reducing Fehling's solution. be done.

In the wastewater treatment agent of the present invention, halogenated first If4
is used as a solution. Examples of the cuprous halide used here include cuprous fluoride, cuprous chloride, cuprous bromide, and cuprous iodide, and any of them may be used, but considering economic efficiency. Cuprous chloride is then most preferred. In order to react uniformly in wastewater, cuprous halide is made into a solution, but cuprous halide is said to be virtually insoluble in water.
It is appropriate to use a suitable solvent such as aqueous hydrogen chloride, aqueous alkali metal halide solution, ethanol, and the like. More specifically, for example, for cuprous chloride, hydrogen chloride water, alkali metal chloride aqueous solution, ethanol, etc. are suitable, and for cuprous iodide, hydrogen chloride water, alkali metal iodide, especially. Suitably, an aqueous potassium iodide solution is used as the solvent. The concentration of hydrogen chloride in the hydrogen chloride water used as such a solvent and the concentration of the alkali metal halide in the aqueous alkali metal halide solution can be adjusted depending on the compatibility of the solvent in the present invention with the cuprous halide mentioned above. It is preferable to select it appropriately in view of the compatibility with the reducing substance described below.

In the present invention, the reducing substance added to the halogenated No. 1g11 solution may be selected from substances capable of reducing Fehling's solution. Preferably used reducing substances include: (1) diluted sulfuric acid and its salts (for example, H2S0a, Na2B
OB, K2S0a, (NH4) 280g, Li25OB
, Naf(S O9, KI(SOs, (Ns4)H8O
8, LiH3O9, etc.)■ Pyrosulfite (e.g., Na
2S2O5, IC28205, etc.)
For example, (NH4)2s204, Na28204, K2
S2O5, etc.) ■ Hypophosphorous acid and its salts (e.g. #-1, HPH202,
zn(,H2PO2)2,AA! (,H2PO2)a,
(NH4)H2PO2, KPH202, G7a (PH
202)2, Co(PH20z)2, Fe(PH202
)2, (Fee(PH202)6)(PH202)8,
NaPH2O2, Pb(PH202)2, N1(PH2
02)2, Ba (P) [202)2, H7 (PH20
2) 2, Mrt(PH202)2 etc.) ■ Phosphorous acid and its salts (e.g. H2PH08, (, NI(4)2PJ(
Oa, (N1(4)HPJ40a, K2PH08, KH
PHOa, 0aPL(Oa, CaH2(PHOa)2
．． 0oPHOa, FePH0s, Fe2CpHOs
)s, Na2PI-JOB, NaEPlloB, Ba
PH0a, BaH2(PHOs)2, (N2H6) P
H0s, N2)16 [H(PHOa))2, My
PHO8, MyH2 (PHOa)2 etc.) (+3.)
Stannous chloride (υ) Phosphines (e.g., PHa, acid addition salts of PH8, PH2 (where R is a hydrocarbon group) and its acid addition salts, RJL'PH (where R is a hydrocarbon group) , both of which may be the same or different) and their acid addition salts; etc.) (manufactured by hydrazines (e.g., NH2NH2, NH,2
NH2・H2O, acid addition salt of hydrazine, Nu)LNJ
i2 (where ■ is a hydrocarbon group) and its acid addition salt, Ni
-uaNm' (However, 几 and 1 are hydrocarbon groups, and both may be the same or different) and its acid addition salt, N几R'
Nu2 (however, IL and R' are hydrocarbon groups and may be the same or different), etc.) Hydroxylamines (e.g. NH2OH and its acid addition salts, NHIILOH (however, R is a hydrocarbon group) )
and its acid addition salts, etc.) (io) Fot-nones (e.g., compounds having substituents such as alkyl groups, halogens, sulfone groups, etc. on the benzene nucleus of hydroquinone, etc.) IC catechols (e.g., catechol , Kateko-At
O) Compounds having substituents such as hydrocarbon groups, halogens, sulfone groups, etc. on the benzene nucleus, pyrogallol, etc.) ■ 0-Aminophenols (for example, 0-aminophenol and N-methyl-〇-aminophenol, and these [ Phase] p-aminophenols (e.g. p-aminophenol and N-methyl-p-aminophenol and acid addition salts thereof, p-aminophenol or N-methyl-p-aminophenol-kO) Compounds having substituents such as hydrocarbon groups, halogens, sulfone groups, hydroxyl groups, etc. in the center nucleus, and their acid addition salts) ■ 0-phenylenediamines (e.g. 0-phenylenediamine and its acid addition salts, N-alkyl, 0-phenylenediamine and its acid addition jM,N,N'-dialkyl-〇-phenylenediamine and its acid addition salt, 0
-phenylenediamine/N-alkyl-0-phenylenediamine or N.

Compounds having substituents such as hydrocarbon groups, halogens, sulfone groups, hydroxyl groups, etc. on the pentene nucleus of N-dialkyl-〇-phenylenediamine, and acid addition salts thereof, etc.) [Phase] p-phenylenediamines (e.g. p-phenylenediamines) Phenyl diamine and its acid addition salts, N-alkyl p-
phenylenediamine and its acid addition salt, N,N'-dialkyl-p-phenylenediamine and its acid addition salt, p
-phenylenediamine/N-alkyl-p-phenylenediamine or N.

Compounds having substituents such as hydrocarbon groups, halogens, sulfone groups, hydroxyl groups, etc. on the pentene nucleus of N'-dialkyl-p-phenylenediamine, and acid addition salts thereof, etc.) 0 l-phenyl-8-pyrazolidones (e.g. 1-
p-oxyphenylglycines (e.g., p-oxyphenylglycine, and acid addition salts or alkali metal salts thereof) [Phase] Formaldehyde sodium sulfoxylate ( (also called Rongarit) are exemplified. They usually have the ability to efficiently reduce Fehling's liquid at room temperature.

These reducing substances may be used alone or in combination of two or more. When selecting a preferable reducing substance, stability and solubility in the solvent for cuprous halide should be considered. Needless to say. For example, when using hydrogen chloride water as a solvent, hypophosphorous acid, phosphorous acid, and the above groups
When an aqueous alkali 7 metal halide solution is used, it is preferable to select from the group consisting of compounds in the form of acid addition salts among groups ■ to ■ and phosphines, and acid addition salts among 0 and p-phenylene diamines. Compounds in the form of salts, group ■ ~ [phase] and group 0 ~ [phase]
When ethanol is used, it is preferably selected from the group consisting of sulfurous acid, hypophosphorous acid, phosphorous acid, and groups ① to ＠.

The proportion of the reducing substance added to the cuprous halide solution is 0.02 equivalent or more per liter of the solution.

If the ratio is less than 0.02 m/l, the effect of the addition of the reducing substance will not be so significant, which is not preferable. A more preferable addition ratio of the reducing substance is 0.05/74/
1 or more, especially 0.1 equivalent M/1 or more. As the addition ratio increases, the stability of the cuprous halide solution over time tends to increase, but in practice, the upper limit is limited by the saturation solubility of the reducing substance in the solution. usually,
It is sufficient to add 2 equivalents/e or less of the reducing substance to the cuprous halide solution.

It should be noted that such additives are hardly influenced by the concentration of cuprous halide in the solution. This is because the reducing substances act to suppress the oxidizing effect of oxidizing substances such as dissolved oxygen present in the solution, and basically directly affect the total amount of dissolved oxygen in the cuprous halide solution. I believe this is because they are related. Therefore, it is usually appropriate to determine the content in accordance with the volume of the solution as described above.

The preparation of the first halogenation solution and the addition and mixing of the reducing substance to the cuprous halide solution are carried out using an inert gas (for example, N
2.002, etc.) is preferably carried out in an atmosphere. Further, the solvent used for preparing the solution preferably has as little dissolved oxygen as possible. However, dissolved oxygen in the solvent and I
If an extra reducing substance is added that reacts with and removes the oxygen that comes into contact with it, the reducing agent prepared in an inert gas atmosphere using a solvent that does not contain dissolved oxygen. Needless to say, it is possible to prepare a solution having performance equivalent to that of a cuprous halide solution containing a chemical substance.

The wastewater treatment agent of the present invention (i.e., the reducing substance-containing cuprous halide solution) not only has a stable quality for a long time from the time of preparation, but also has a thiocyanine content (C3ON-) in the wastewater immediately after preparation. Even when used to remove thiocyanide (free cyanide and complex cyanide), it has been found to have superior performance in removing thiocyanide and cyanide than the cuprous halide solution that does not contain the reducing substance. Ta. In other words, even when removing thiocyanide and cyanide from wastewater using a cuprous halide solution immediately after preparation, a cuprous halide solution containing 0.02 or more of the reducing substance/l is used.
When a copper solution is used, the residual thiocyanate concentration and residual cyanide concentration in the wastewater after treatment tend to be lower, and the variation in the obtained values tends to be smaller. The reason for this is unknown, but it may be that when the cuprous halide solution is added to and mixed with wastewater, it comes into contact with air or is affected by dissolved oxygen in the wastewater.

Regulations on the concentration of thiocyanine in wastewater discharged outside the factory are not as strict as those for cyanide, as the toxicity of thiocyanine is significantly weaker than that of cyanide, but regulations on the concentration of cyanide are extremely strict, at 0.21v. /e or less is desired. Although diluting and discharging is permitted, in areas where the residual cyanide concentration is 1 ml/II or less, even if the concentration decreases by about 0.1 W/n, it will have a large effect on the dilution ratio. The practical significance is extremely large.

From this point of view, the reduction in the concentration of residual cyanide in wastewater treated with the wastewater treatment agent of the present invention is a practically significant and unexpected effect.

The wastewater treatment agent of the present invention is used to remove thiocyanine and cyanide from wastewater.
If S) is contained, it also reacts with sulfur ions to form a precipitate, and cuprous halide is wasted. In order to avoid this, for wastewater containing sulfur ions, for example, ferrous ions (Fe") or ferric ions (yea+) are used to form iron sulfide precipitates in advance, and this precipitate is separated. It is preferable to remove sulfur ions in advance by a method such as removing the sulfur ions.

It has been found that even if cyanide is present in wastewater in the form of cyanide or complex cyanide, by using the wastewater treatment agent of the present invention, cyanide can be separated and removed by forming a precipitate.

Therefore, in the method of the present invention, a total of 972 minutes, which is the total of free cyanide ions and complex cyanide ions, can be treated on the assumption that they are all free cyanide. Therefore,
When treating wastewater using the wastewater treatment agent of the present invention,
011 + 5ON--CuSON-- (Formula I) Ou + ON'--0uON for cuprous halide
...(formula) 20u + 8 -40u2B
- The amount to be used may be determined in consideration of the reaction of (Formula I). That is, in the case of the wastewater treatment agent of the present invention, the stoichiometric equivalent of cuprous halide necessary to remove thiocyanide and cyanide is ['mono-spray of cuprous halide] = (SON- c: number of floating ions〕-t〔4th gram of CN-) + 2(S2
- Gram ion number J... (Formula 2) (However, ON- is all cyan including complex cyan). Needless to say, if the wastewater does not contain thiocyanine, cyanide, or sulfur ions, the number of gram ions of the ions in equation (2) may be treated as zero. If the purpose is to reduce the thiocyanide content in wastewater, cuprous halide may be added to the wastewater in an amount smaller than the stoichiometric equivalent, but in other cases it is usually Preferably, a theoretical equivalent amount or an excess of cuprous halide is added to the wastewater.

When ammonia is present in wastewater, a complex ion (0u(NHs)2) is formed when cuprous halide is added to the wastewater, and the solubility of the reaction product between Ou+ and thiocyanide or cyanide increases. This may increase the removal efficiency of thiocyanide or cyanide.To avoid this, for example, formaldehyde can be added to the wastewater to remove ammonia and/or ammonium ions (due to chemical equilibrium, a small amount of ammonia is always added). It is preferable to inactivate ammonia in wastewater by, for example, converting ammonia (produced by contains ammonium ions and is alkaline.

If there are oxidizing components in the wastewater, when cuprous halide is added to the wastewater, Cu+ will be oxidized and converted to Cu2+, and the solubility of the reaction products with thiocyanine and cyanide will increase and these Removal efficiency may decrease. The wastewater treatment agent of the present invention contains a certain amount of reducing substance to prevent the O contained in the wastewater treatment agent from converting into Ou. Such a problem arises when a non-negligible oxidizing component is contained in the product. In order to avoid this, it is preferable to add a reducing substance to the wastewater in advance to treat the oxidizing components before adding the cuprous halide.

When wastewater treatment using the wastewater treatment agent of the present invention is carried out under strongly alkaline conditions, undesirable side reactions tend to occur in cuprous halides, so it is preferably carried out at a pH of 9 or less. More preferably, the treatment should be carried out under p) 18.1 or less, which is a condition in which the reaction between cuprous ions and thiacyanide or cyanide proceeds substantially quantitatively; however, when the pH is below 8.1, Even if the pH is high, if the pH is 9 or less, the purpose of wastewater treatment can be achieved by adding a slight excess of cuprous ions. If the pH is higher than 9 J, cuprous ions will be added in considerable excess. If the wastewater treatment agent uses hydrochloric acid as a solvent, the pH after adding the wastewater treatment agent to the wastewater may be 9 or less (more preferably 8.1 or less), but the wastewater treatment When the solvent used in the agent is other than hydrochloric acid, it is preferable to adjust the pH of the wastewater to 9 or less (more preferably 8.1 or less) before adding the wastewater treatment agent.

On the other hand, acidic wastewater can be treated without adjusting the pH in advance.

Since the reaction between halogenated i1m and thiocyanide and cyanide in wastewater proceeds at room temperature, there is no need to particularly heat or cool the wastewater when treating it with the wastewater treatment agent of the present invention. It's okay.

To separate the generated precipitate from the treated water, any conventionally known solid-liquid separation means can be used, such as filtration, centrifugation, or separation into precipitate and supernatant in a precipitation tank. This solid-liquid separation is also preferably carried out at a pH of 9 or lower, particularly at a pH of 8.1 or lower.

Copper ions are contained in wastewater treated with the wastewater treatment agent of the present invention. To remove copper ions, conventionally known methods may be used, such as adding hydrogen sulfide or sodium sulfide in a stoichiometric equivalent amount or a slightly excess amount to copper ions to precipitate copper sulfide. The precipitate can be easily removed by, for example, generating a precipitate and removing the precipitate.

Since the wastewater treatment agent of the present invention contains a reducing substance capable of reducing Feirinda liquid, the ability to remove thiocyanine and cyanide (free cyanide ions and complex cyanide ions) from wastewater is significantly improved. This reduces the variation in the residual thiocyanate concentration and residual cyanide concentration in the wastewater after treatment, and also significantly improves the temporal deterioration of the performance of the wastewater treatment agent. It has the characteristic of being stable.

Hereinafter, the present invention will be explained in detail with reference to Examples.

In addition, thiocyanate ion is thiocyanate ion and F
(Fe(NO8)) produced by reaction with e
The red color due to 2+ was measured at a wavelength of 480 n by spectrophotometry.
Measured in m.

In addition, cyan ions were added to JIS-0102 (1
It was measured by the 4-pyridinecarboxylic acid-vilazolone spectrophotometric method shown in 981)-88,8. Therefore, the so-called total 97, including not only free cyanide but also complex cyanide.
It measures 2 minutes.

The method for quantifying the reducing substance contained in the wastewater treatment agent is to select one from among the oxidizing agent solutions (for example, KMnO4 aqueous solution, K20r207 aqueous solution, etc.) used for ordinary redox titration depending on the pH of the wastewater treatment agent, etc. The number of equivalents of the reducing substance and Cu+ oxidized using the selected reagent is determined, and on the other hand, the copper content contained in the wastewater treatment agent is determined, and the number of equivalents oxidized with the oxidizing agent solution is determined. Of which, all the copper content is
A method was used in which the amount of the reducing substance contained in the wastewater treatment agent was determined by subtracting the number of equivalents calculated as the conversion of Cu+ to Cu2+.

Example 1 and Comparative Example 1 In order to easily confirm the effect of cyanide removal by cuprous chloride solution immediately after preparation, free cyanide, (Fe CN) a
J'su [Fe(CN)6]8-1Na+, K+, Oa
p containing 2+, M, 2+, Cl1- and 5042-
A model wastewater of H6 was created.

A total of 972 min in the model wastewater is 1 oxv/(IQ, of which free cyanide is 4 Wlf//l, and the rest is complex cyanide, which is 3 cyanide in the form of (Fe (ON)e)'-. /1((Fe(ON)6)' (!:
I, Cl4.07 IIy/ (1), (Fe(ON)
6. )3-, the cyan component is 8W/(1((
Fe(ON)6)8- was 4.07 da/(').

Cuprous chloride solutions were prepared from the following four yuzu types with different cyclic substance contents.

0uO1l! Dissolution RA: Curl concentration 19.041
1/l, Na1l concentrated IQ: 150 f/l, the remainder consists of water.

Curl solution W'iB: (UuC1 concentration 19.04
f/(1, Na(V thick JJ[150f/It, HiF
o/2711 degrees 2-20 f/(J (0.04 equivalent/l), the remainder consists of water.

Ou 011 solution 0: OuC! # 9 degrees 19.04
f/(J, Na1l concentration 150F!/6. Hydroquinone concentration 4.40f/1 (0.08 equivalent tl&/l),
The remainder consists of water.

Ou(M solution D: Cu069 degrees 19.04 f/7
? , Na0A' concentration 150f/11. Hydrazine concentration 0
．． 64 f/11 (0.08/l), the rest consists of water.

First, 800 f of boiled hot water was placed in a nitrogen atmosphere, and N
a (M150g was dissolved in the hot water, then 0u06
1.9.04 After dissolving f/, let it cool, and if necessary, add and dissolve a specified range of hydroquinone or hydrazine (used in the form of hydrate), and then boil it. Water that had been allowed to cool in a nitrogen atmosphere F was added to bring the total volume to 14, and the mixture was kept in a nitrogen atmosphere until just before addition to the wastewater, and was added to the wastewater within 1 hour after preparation.

The Cu0j? per model wastewater 1004 exposed to air atmosphere? After adding a predetermined amount of solution (see Table 1) and stirring well, the mixture was allowed to stand for 30 minutes to allow the formed precipitate to settle, and then the precipitate was filtered, and a total of 972 minutes of the resulting P solution was measured. The experiment under the same conditions was repeated three times using different lots of model wastewater and different lots of CuCl solution. Table 1 shows the maximum value, minimum value, and average value of the residual cyanide concentration of the obtained P solution. Note that experiment numbers 1 to 4 are experiments in which a stoichiometric equivalent amount of CuC1 necessary to form 0 uCN was added to a total of 972 minutes in the model wastewater.

From the results in Table 1 and above, it can be concluded that (υ cuo1! solution added to wastewater can remove not only free cyanide ions but also complex cyanide ions in wastewater).
When a solution is used, the total cyanide concentration in the P solution decreases, and furthermore, the variation in the total cyanide concentration due to the different lofts of wastewater and OuC# solution is reduced. It can be seen that if they are added in such a way that the number of reducing equivalents is equal, the same effect will be achieved.

Example 2 and Comparative Example 2 Immediately after preparation, the CuC1 solutions A and C were transferred to a storage tank under an air atmosphere, and the tank was sealed with a lid in the air atmosphere and stored for 24 hours. 1
It was added to a model wastewater having the same composition as that used in Comparative Example 1 under the same operating conditions as in Example 1 and Comparative Example 1 to remove cyanide. The experiment under the same conditions was repeated eight times by changing the lot of model wastewater and the lot of 0 ucl solution. (!u
Addition of OJ solution (first 1) (and total cyanide concentration of P solution 2nd)
Shown in the table.

Comparing the results in Table 2 and above with the results in Table 4N1, OuC, which does not contain reducing substances! It can be seen that when the CuCl1 solution is stored in a hermetically sealed state in an air atmosphere, the ability to remove cyanide is significantly reduced, but this drawback can be improved by incorporating a reducing substance into the CuCl1 solution.

Example 3 and Comparative Example 8 SON- was 111. ．． 511g/l containing t 71.1.
(KaC1-1so42-1OHa00(f, Na+, K
A model wastewater with a pH of 6.5 containing Oa2+, Oa2+ and My was prepared.

The Ou(M solutions A and C used in Example 1 and Comparative Example 1 were added to this model wastewater, stirred well, and stirred for 30 minutes to allow the formed precipitate to settle. After that, the precipitate was filtered. The thiocyanide content of the obtained furnace liquid was measured.

At this time, Curl solutions A and C should be added to the wastewater within 1 hour after preparation, and either they should be placed in a nitrogen atmosphere until just before they are added to the wastewater, or they should be transferred to a storage tank under an air atmosphere immediately after preparation and placed in an air atmosphere. Two experiments were conducted: the tank was sealed with a lid and stored for 24 hours, and then added to the wastewater.

Table 3 shows the experimental conditions and the thiocyanate concentration of the P solution.

Note that in these experiments, 0uC1 was added in a stoichiometric equivalent amount to form Ou SO ON.

From the results shown in Table 3, it is clear that when a cuprous chloride solution that does not contain a reducing substance is exposed to air, its ability to remove thiocyanate decreases, but when a reducing substance such as hydroquinone is added, this drawback can be overcome. It can be seen that it is improved.

Example 4 The same model wastewater as used in Example 1 was prepared using the OuO&+ solution in which another reducing substance was added instead of the reducing substance (i.e., hydroquinone or hydrazine) added to the Ou(M solution) in Example 1. The cyan content inside was removed.

The composition of the prepared Ou(M solution is as follows.

Curl solution ME: 0uC1l 9 degrees 19.04 f
/l, Na1l (7% degree 150 f/(1, Na
25Oa concentration 5.04 f/11 (0.08 equivalent MVl
), the rest consists of water.

OuC# solution F: Gu06 concentration 19.04 Ve
1Na (34 to concentration 150 f//l, K2820
5 concentration 4.45'! /l (0.08 equivalent m/(1),
The remainder consists of water.

OuO# solution G: Curl concentration 19.049/l
, Na1l concentration 150 f/I! , Na28204
i Agricultural production 2.82 f/l (0.08 equivalent M/l), the remainder consisting of water.

CuC1 solution H: Cu(V concentration 19.04 f/1
2. Na0A' concentration 150 Q/l! , NaP
R202 concentration 1.76 f/(1(0.08 equivalent M(1)
, the rest consists of water.

0uOJ solution I: Curl concentration 19.049/(1
%Na01 concentration 150 'i/(1), Na2PHOB concentration 5.04971 (0.08 equivalent tjk/l), the remainder consists of water.

Ou(M solution J: Curl mW 19.04 g
/11NaOII concentration 150f/l, catechol concentration 4
．． 40 f/l (0.08 equivalents/II), the remainder consisting of water.

Ou (MW4 liquid K: 0uON concentration 19.0411/
l 1NaOJ concentration 150 f/11, 0H20H8
O2Na・2H2O concentration 8.08 f/l (0,08
(@/l), the rest consists of water.

First, 800 y of boiled hot water was placed in a nitrogen atmosphere, and N
aC6150y was dissolved in the hot water, then 0uOJ
19.04 After dissolving f, let it cool, and then add and dissolve a certain amount of oxidizing substance, and then add water that had been left to cool in an atmosphere of simmering and post-nitrification to make the whole In. It was placed in a nitrogen atmosphere until just before addition to the wastewater and was added to the wastewater within 1 hour after preparation.

Model wastewater exposed to air atmosphere (of the same composition as used in Example 1 and Comparative Example 1) per toog,
After adding the predetermined amount of the above 011 (M solution (see Table 4) and stirring well, let it stand for 30 minutes to settle the formed precipitate, and then filter the precipitate to obtain a total cyan content of the P solution. was measured.The obtained results are shown in Table 4.Experiment No. 2
1 to 27 are 0uON for the total cyanide content in the model wastewater.
In this experiment, the stoichiometric equivalent of CuClt required to form .

In addition, 0uCJ solution H"K was prepared at 11
The P solution was then transferred to a storage tank under an air atmosphere, the tank was sealed under the air atmosphere, and the P solution was stored in the same manner as in Experiments 21 to 34, except that it was stored for 24 hours and then added to the wastewater. When the total cyan partition degree' was measured, the results agreed with the results in Table 4 within the experimental error range.

Comparing the above results with experiment numbers 3.4 and 7°8 in Table 1 and experiment numbers 14 and 16 in Table 2, C! uC
It can be seen that 1(d/&E ”□K also has the same performance as Ou(M solutions C and D).

Example 5 and Comparative Example 4 Cu0I with the following blending ratio in an air atmosphere! A solution was prepared.

Curl solution L: Quill concentration 89.69/l
(0.4 mol/l), Na01 concentration 200 fl/11
, the rest consists of one water.

0uO1M liquid M: Curl concentration 89.6 f/l
(0,4 monobite 1), Na0118 degree 2009/(1,
8n01!2 concentration 18.97f/11 (0.2 equivalent/
l), the remainder consisting of water.

First, Na 01120 was added to 650f of hot water in an air atmosphere.
After dissolving 0f and then cooling it, 0uO1t39,
Add 69 to dissolve, and then add 5no to solution M only.
d2 was added followed by water to bring the total to 14. The obtained j:0u01 solution was transferred to a storage tank under an air atmosphere, the tank was sealed with a lid under the air atmosphere, and stored for 24 hours, after which 1 was added to the waste water.

Wastewater is 5ON-290W/L total cyanide content 65"
In addition to containing 9/l 5NH4+ at a ratio of 541, c
e-1SO42-1Zn, Fe, Ca, M
y, Na+, and Ni+, and pI (was 6.5).

Further, the amount of reducing substances (excluding Cu+) contained in the CuC1 solution M immediately before being added to the wastewater was 0.14 equivalent/e.

After adding 2.25 # of Ou (M solution) per 1001 wastewater and stirring, the resulting precipitate was filtered after being allowed to stand for 80 minutes, and the thiocyan content and total cyan content of the obtained P solution were measured. The results are shown in Table 5.

Table 5 In these experiments, a
Adding the url. From the results in Table 5, it can be seen that in the case of a CuCe solution that does not contain a reducing substance, the quality deteriorates due to storage, but this defect can be improved by containing a reducing substance. Furthermore, regarding the removal of total cyanide, there is a significant difference in effectiveness between using a CuCe solution containing a reducing substance and using a CuCe solution containing no reducing substance.

Example 6 and Comparative Example 5 A CuCe solution having the following composition was prepared.

0uOj? Solution N: 0u (37? Concentration 95.19
'l/l, HCI concentration 245971, remainder consists of water.

0uC1 solution Q: Curl concentration 95.1997/e
, H (Jfi degree 245 f/l, hydroxylamine concentration 6.61 f/l (0.2 eq/l), the remainder consists of water.

0uOj! Solution P: Ou (M 9 degrees 95.19 f
/l, Hog 9 degrees 2451 // 1,0-aminophenol concentration 10.9 f/l (0,2 equivalent fJ, /l), the remainder consists of water.

OuO# solution Q: CuCII concentration 95.19 f/
l, HOI @ degree 2459/β, N-methyl-p-aminophenol sulfate concentration 17.2 f/l (0,
2 equivalents tA), and the remainder consists of water.

CuC11 dissolved f&R: Cu0II concentration 95.19 f
//l, Hog concentration 245 f/11, O-phenylenediamine concentration 10.89/l (0,2 equivalent'#7'l
), the rest consists of water.

0uOn solution 8: CuO1 concentration 95.191/II
, 1101 concentration 245 f/l, ¥)-phenylenediamine concentration 1O18 and τ(0,2 equivalent Mg), and the remainder consists of water.

CuO1! Solution T: 0uO 114 degrees 95.19 f
/1. Hoe concentration 245Lτ, ■-phenyl-3-virazolidone concentration 16.2 f/l (0.2 hit 70,
The remainder consists of water.

0uOA' solution U: Curl concentration 95.19 f/
11. HCI concentration 245 f/e, '9-oxyphenylglycine concentration III 6.7 f/(1 (0.2 equivalent m/
l), the water that remains will be left behind.

First, 700f of 35% concentrated hydrochloric acid was placed in a nitrogen atmosphere, and Cu
rl 95.19 f and a predetermined amount of a predetermined reducing substance were added and dissolved, and water was further added to bring the total volume to 1 l. A portion of the resulting Curl solution was placed under a nitrogen atmosphere immediately prior to addition to the wastewater and was added to the wastewater within 1 hour of preparation.

Immediately after preparation, the remainder of the OuO1 solution was transferred to a storage tank under an air atmosphere, and the tank was sealed with a lid under an air atmosphere and stored for one week before being added to the wastewater.

A model wastewater having the same composition as that used in Example 1 and Comparative Example 1 was used as the wastewater, and a predetermined amount of the above (JUCJL solution (see Table 6) was added per 1001 of the model wastewater exposed to the air atmosphere. After stirring, the resulting precipitate was filtered after being allowed to stand for 80 minutes, and a total of 972 minutes of the obtained furnace liquid was measured.The obtained results are shown in Table 6.Experiment numbers 37 to 4
4 is OuC for a total of 972 minutes in the model wastewater! This is an experiment in which the stoichiometric equivalent of 0u (31) necessary to form N was added.

Table 6 Actual Wastewater used: 1001 IF' liquid total: 97
2 minutes or.

No. 011゜l IQ Curl solution -"-'-CI
- Addition range of IJ'iljffM test, 6 cases, 4 minutes, liquid ``<119/l) case (comparison of 87 NO, 0401, 81, 7100
,0400,400,42 89p O,0400J9 0.89
This book-----1---------=-------m=
---40Q O,0400J8 0.
40 shots 41 110.040 0.42 0.414
2 f3 0.040 0.41
0.41 light--------=--1----
---------48T O,0400,890
,4044jJ O,0400,400,89
Comparison 45 N O,060,11911,4
46Q O, 0600, 280, 2847p
O, 0600, 290, 80 pieces -----
---------1----48Q 0.
060 0.27 0.29 49 1L
0.060 0.80 0.805OS O
,0600,810,29 Ming
−1−−−−−−−−−−K l
m n n c ha ha on
From the results above, it can be seen that the wastewater treatment agent of the present invention has a lower
It can be seen that the performance of removing cyanide from wastewater is excellent, and the low quality F in stored iJB is significantly improved.

t) Example 7 and Comparative Example 6 ---- Ou(M
Solution N.

Thiocyanate content in wastewater using 0, Q, S and U---
- was removed. As wastewater containing thiocyanate, -
m = Model wastewater having the same composition as used in Example 3 and Comparative Example 3 was used.

1'' - To this model wastewater, add the specified Curl solution (prepared within 1 hour or stored for 1 week), stir well, and let stand for 30 minutes to settle the formed precipitate. After that, the precipitate was filtered and the thiocyanide content of the obtained furnace liquid was measured.The obtained results are shown in Table 7.In these experiments, 0uOJ was changed to the stoichiometry for forming 0uSON. Only the appropriate amount is added.

From the results in Table 7 and above, it can be seen that the wastewater treatment agent of the present invention significantly improves the low quality F during storage compared to the 0uCV solution that does not contain reducing properties or substances.

Example 8 and Comparative Example 7 C! has the following composition: A uon solution was prepared.

0uOJ? Solution V: Curl concentration 200 f/l,
HCjl concentration is 815 fyτ, the remainder consists of water.

Curl solution W: Curl concentration 200 f/l,
H01 concentration 815 f/11, hydrazine concentration 8.2
f/l (0,4 fJ, A), and the rest consists of water.

First, place 900 g of 35% concentrated hydrochloric acid in a nitrogen atmosphere, add and dissolve OuO#20Of into the hydrochloric acid, and then add hydrazine (8.29 <used in the form of hydrate) only to solution W. Afterwards, water was added to bring the whole mixture to H.

A portion of the resulting Curl solution was placed under a nitrogen atmosphere immediately prior to addition to the wastewater and was added to the wastewater within 1 hour of preparation. The remainder of the cuce solution was immediately transferred to a storage tank under an air atmosphere after preparation, and the tank was sealed with a lid under an air atmosphere and stored for two weeks before being added to the wastewater.

The wastewater used had the same composition as that used in Example 5 and Comparative Example 4.

Further, the amount of reducing substances (excluding Ou+) contained in the OuOJ solution W after storage for 2 weeks was 0.31 equivalent/l.

Add 0.4 parts of Curl f15 solution per 100 parts of wastewater, stir with water, let stand for 30 minutes, and remove the formed precipitate.
The thiocyan content and total cyan content of the obtained P solution were measured. The results obtained are shown in Table 8.

Note that in these experiments, Curl was added in an amount of about 106.7% of the required stoichiometric equivalent to the total of thiocyanide and total cyanide.

From the results shown in Table 8, the wastewater treatment agent of the present invention does not dowel reducing substances. It can be seen that the ability to remove all cyanide is significantly improved compared to Solution 6, and quality deterioration during storage is significantly improved.

Example 9 A OuclI solution was prepared with the following composition.

OuOg solution X: 0uC121j 1 degree 200 f/
11, HCjl concentration 315 f/11, H4F
, ) iog 82.8 fiτ (0,8 equivalents/l), the remainder consisting of water.

First, 900f of 35% concentrated hydrochloric acid was placed in a nitrogen atmosphere, 0uOA'200jF was added and dissolved in the hydrochloric acid, H2PHOa (used in the form of an aqueous solution) was added, and then water was added to bring the whole mixture to 11 I made it. The obtained CjuC
1 solution was immediately transferred to a storage tank under an air atmosphere, the tank was sealed with a lid under an air atmosphere, and stored for 4 weeks before being added to the wastewater. The reducing substance contained in the 0uC6 solution X after storage for 4 weeks was 0.6 g equivalent/l.

The wastewater used was from a plating factory. The quality of this wastewater was as follows.

Total cyanide content 88.5ηq, Iron 32nd (free cyanide 2.0η4) Nickel 5 Mfl/1 Total chromium content 105 da/11 Zinc 1.6η4 (
Hexavalent') o M98Wvl) Sulfate ion 285j
%'/A' Copper 0.1 ■ 4, Chlorine ion 62 shells 4 pH 6,4 This wastewater is led to a chromium treatment tank, hexavalent chromium is reduced to 31 dli chromium, and the pH is adjusted to 8.6.
11 to form a chromium hydroxide precipitate, and this precipitate was removed. The waste water after removing the precipitate was led to a cyanogen treatment tank, and after adding 8.04 ml of CuC1 solution per 10,001 ml of waste water and stirring, it was allowed to stand still for 30 minutes.

The concentration of total cyanide remaining in the P solution after filtering the generated precipitate was 0.07 mf/(l).

Claims (1)

[Scope of Claims] 1. A treatment agent for cyanide and/or thiocyanide-containing wastewater with improved stability and treatment efficiency, which comprises a cuprous halide solution containing a reducing substance capable of reducing Feirinda liquid. 2. The reducing substance is sulfite and its salts, pyrosulfite,
Nithionic acid, hypophosphorous acid and its salts, phosphorous acid and its salts, tin chloride, phosphines, hydrazines, hydroxylamines, hydroquinones, catechols, 0-
Aminophenol L p-aminophenols, 0-phenylenediamines, p-phenylenediamines, 1-
The processing agent according to claim 1, which is one or more compounds selected from the group consisting of phenyl-8-pyrazolidones, p-oxyphenylglycines, and formaldehyde sodium sulfoxylate. 8. Claim 1 or 2, wherein the cuprous halide solution is a 1% by weight to saturated solution of cuprous halide in hydrogen chloride water, alkali metal halide aqueous solution, or ethanol as a solvent. The processing agent described in . 4. The reducing substance is 0.0% per 11 cuprous halide solutions.
The processing agent according to any one of claims 1 to 8, which contains 02 or more.