Treatment and resource recycling method of electroplating cyanide copper wastewater

Abstract

The invention discloses a treatment and resource recycling method of electroplating cyanide copper wastewater, and belongs to the technical field of electroplating wastewater treatment. The method comprises the following steps: carrying out strong base regulation on the cyanogen copper wastewater, and putting a ferrous sulfate solution into the cyanogen copper wastewater subjected to strong base regulation to carry out binding reaction; adding acid to adjust the cyanide copper wastewater after the binding reaction, and carrying out Prussian blue reaction; adding a coagulation aid agent into the solution after the Prussian blue reaction, and carrying out solid-liquid filtration separation on the solution to obtain ferricyanide mud and preliminarily precipitated cyanogen-removed wastewater; carrying out weak base regulation on the preliminarily precipitated cyanogen-removed wastewater, adding hydrogen peroxide into the preliminarily precipitated cyanogen-removed wastewater subjected to weak base regulation, and carrying out oxidation reaction by using copper in the preliminarily precipitated cyanogen-removed wastewater subjected to weak base regulation as a catalyst so as to remove residual cyanogen-containing pollutants; and after the oxidation reaction is finished, lime is added for flocculent precipitation to obtain copper sludge, so that the copper cyanogen compound is converted into a recyclable resource through a one-time technological process, and the resource utilization rate is increased.

Description

Technical Field

[0001] The present application relates to the technical field of electroplating wastewater treatment, and in particular to a method for treating and recycling electrocyanide copper wastewater. Background Art

[0002] The commonly used method for treating cyanide copper wastewater is the alkaline chlorination method, the principle of which is to utilize the oxidizing property of chlorine-containing oxides (such as sodium hypochlorite, chlorine dioxide, liquid chlorine, bleaching powder, etc.) to first oxidize and hydrolyze cyanide-containing compounds into less toxic cyanates under alkaline conditions, and then further oxidize them into non-toxic bicarbonates and nitrogen, thereby achieving the removal of cyanide-containing compounds and heavy metals.

[0003] However, in the process of treating copper cyanide wastewater by alkaline chlorination, the pollutant cyanide can be destroyed by the chloride ion, and the cyanide compound can be decomposed into bicarbonate and nitrogen. However, this method does not recycle the cyanide, which reduces the utilization rate of copper cyanide wastewater resource recovery. Summary of the invention

[0004] The main purpose of the present application is to provide a method for treating and recycling copper cyanide electroplating wastewater, aiming to solve the technical problem of not recycling cyanide and reducing the utilization rate of copper cyanide resource recovery.

[0005] To achieve the above-mentioned purpose, the present application provides a method for treating and recycling copper cyanide electroplating wastewater, and the method for treating and recycling copper cyanide electroplating wastewater comprises the following steps:

[0006] The copper cyanide wastewater is subjected to strong alkali conditioning, and a ferrous sulfate solution is added to the copper cyanide wastewater after strong alkali conditioning to carry out a binding reaction, and the pH value of the solution during the entire binding reaction process is controlled to be 10-11, so that the ferrous sulfate solution and the cyanide in the copper cyanide wastewater are subjected to a binding reaction to generate ferrocyanide ions, wherein the reaction time of the binding reaction is 1-2 hours;

[0007] Acid is added to the copper cyanide wastewater after the combination reaction, and a Prussian blue reaction is performed when the pH value thereof is 4.5 to 5.5, so that the ferrous ions in the copper cyanide wastewater after the combination reaction react with the ferrocyanide ions first, and the copper in the copper cyanide wastewater after the combination reaction is freed in the solution;

[0008] Adding a coagulant aid into the solution after the Prussian blue reaction, and subjecting it to solid-liquid filtration separation to obtain ferrocyanide mud and preliminary precipitation cyanide removal wastewater, wherein the ferrocyanide mud is used as a raw material for resource processing of hematoxylin;

[0009] The preliminary precipitation cyanide removal wastewater is subjected to weak alkali adjustment, hydrogen peroxide is added to the preliminary precipitation cyanide removal wastewater after weak alkali adjustment, copper in the preliminary precipitation cyanide removal wastewater after weak alkali adjustment is used as a catalyst for oxidation reaction, and the pH value of the solution during the entire oxidation reaction process is controlled to be 6.5-7.5 to remove the remaining cyanide-containing pollutants, wherein the reaction time of the oxidation reaction is 1-2 hours;

[0010] After the oxidation reaction is completed, lime is added for flocculation and precipitation to obtain copper mud, wherein the copper mud is subsequently processed for resource recovery.

[0011] In one embodiment, the cyanide-copper wastewater contains at least free cyanide and copper-cyanide complex;

[0012] According to the stability constant of the copper-cyanide complex, the solubility product of ferrocyanate and the pH value during the corresponding reaction, the ferrous ions are first reacted with the cyanide in the copper-cyanide complex, and then reacted with the copper ions in the copper-cyanide complex, so that the cyanide is preferentially transferred and separated, and a precipitate of ferrocyanide mud is generated.

[0013] In one embodiment, the reagent used for the strong base adjustment and the weak base adjustment is NaOH, and the mass concentration is 10% to 30%.

[0014] In one embodiment, the mass concentration of the ferrous sulfate solution is 10% to 25%.

[0015] In one embodiment, the agent used for the acid adjustment is hydrochloric acid or sulfuric acid, the mass concentration of the hydrochloric acid is 10%~30%, and the mass concentration of the sulfuric acid is 10%~40%.

[0016] In one embodiment, the coagulant aid is polyaluminium chloride and / or polyacrylamide, wherein the mass concentration of the polyaluminium chloride is 5-10%, and the mass concentration of the polyacrylamide is 0.5-1.0%.

[0017] In one embodiment, the solid-liquid filtration separation method is plate and frame filter pressing.

[0018] In one embodiment, the mass concentration of the hydrogen peroxide is 7%.

[0019] In one embodiment, the lime component is Ca(OH)2 with a mass concentration of 10% to 20%.

[0020] One or more technical solutions proposed in the present application have at least the following technical effects: by subjecting the copper cyanide wastewater to strong alkali adjustment, adding ferrous sulfate solution to the copper cyanide wastewater after strong alkali adjustment for a combination reaction; acid-adjusting the copper cyanide wastewater after the combination reaction, and performing a Prussian blue reaction; adding a coagulant to the solution after the Prussian blue reaction, and performing solid-liquid filtration separation to obtain ferrocyanide mud and preliminary precipitation decyanation wastewater; subjecting the preliminary precipitation decyanation wastewater to weak alkali adjustment, adding hydrogen peroxide to the preliminary precipitation decyanation wastewater after weak alkali adjustment, and using the copper in the preliminary precipitation decyanation wastewater after weak alkali adjustment as a catalyst An oxidation reaction is carried out to remove the remaining cyanide-containing pollutants; after the oxidation reaction is completed, lime is added for flocculation and precipitation to obtain copper mud, thereby realizing a one-time process flow, preferentially reacting cyanide in the copper cyanide wastewater with ferrous ions to generate ferrocyanide ions, and converting them into ferrocyanide mud through a Prussian blue reaction, and using copper ions in the wastewater after subsequent cyanide removal to assist in coagulation and precipitation to obtain copper mud, thereby realizing the conversion of copper cyanide compounds in the copper cyanide wastewater into recyclable copper resources and cyanide resources, respectively, thereby realizing the recovery efficiency of various element resources in the copper cyanide wastewater, thereby improving the resource utilization rate of the copper cyanide wastewater. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0023] Figure 1 A schematic diagram of a process for treating and recycling copper cyanide electroplating wastewater according to the present invention;

[0024] Figure 2 This is a schematic diagram of the overall process flow of the method for treating and recycling copper cyanide electroplating wastewater in this application.

[0025] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0026] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0027] It should be noted that in the current prior art, the main process of the treatment plan for wastewater containing copper cyanide compounds usually includes destroying cyanide and converting the nitrogen element contained therein into nitrogen gas, and extracting the heavy metals in the wastewater after removing the cyanide and reusing the resources. In this process, the recovery and utilization of cyanide is not taken into account.

[0028] In addition, most of the above treatment schemes involve alkaline oxidation methods, which first oxidize and hydrolyze cyanide compounds into less toxic cyanate under alkaline conditions, and then further oxidize them into non-toxic bicarbonate and nitrogen, thereby achieving the removal of cyanide compounds and heavy metals. However, in addition to not considering the issue of cyanide recycling, it also includes the following issues:

[0029] 1. The cost of reagents for the alkaline chlorination method is high; 2. The alkaline chlorination method introduces a large amount of chloride ions when treating copper cyanide wastewater, and the chloride ions cannot be effectively removed in the subsequent process, which has a great impact on the biochemical system, reuse and evaporation system; 3. The alkaline chlorination method can remove most of the complex cyanide, but cannot decompose the ferrocyanide complex.

[0030] Based on the four problems described above, the present application embodiment provides a method for treating and recycling copper cyanide electroplating wastewater, referring to Figure 1 , Figure 1 This is a flow chart of the first embodiment of the method for treating and recycling copper cyanide electroplating wastewater of the present application.

[0031] In the first embodiment, the method for treating and recycling copper cyanide electroplating wastewater comprises the following steps:

[0032] S10, subjecting the copper cyanide wastewater to strong alkali conditioning, adding a ferrous sulfate solution to the copper cyanide wastewater after strong alkali conditioning for a binding reaction, and controlling the pH value of the solution during the entire binding reaction process to be 10-11, so that the ferrous sulfate solution and the cyanide in the copper cyanide wastewater are subjected to a binding reaction to generate ferrocyanide ions, wherein the reaction time of the binding reaction is 1-2 hours;

[0033] It should be noted that the cyanide / copper cyanide wastewater involved in this embodiment specifically refers to cyanide / copper cyanide wastewater, which mainly contains free cyanide (CN - ), copper cyanide complex (mainly in the form of Cu(CN) 3 2- ) and zinc cyanide complex (Zn(CN) 4 2- )wait.

[0034] In this embodiment, when the copper cyanide wastewater is subjected to strong alkali adjustment, the reagent used can be NaOH with a mass concentration of 10% to 30%. During the strong alkali adjustment process, an independent pH adjustment tank can be planned, and the copper cyanide wastewater and NaOH are added to the pH adjustment tank together, and corresponding stirring and mixing actions are performed.

[0035] In this embodiment, after the copper cyanide wastewater is subjected to strong alkali adjustment, the overall idea of ​​the treatment process for the copper cyanide wastewater is to preferentially remove the cyanide in the copper cyanide wastewater, and then precipitate the heavy metals in the wastewater after the cyanide is removed. In the process of removing the cyanide, in order to ensure the recycling of the cyanide, a combination reaction is adopted to combine the cyanide with the iron element to obtain ferrocyanide mud.

[0036] Specifically, the ferrous sulfate solution is added to the copper cyanide wastewater adjusted with a strong alkali to allow the two to react with each other. At the same time, the pH value of the solution in the entire pH adjustment tank is controlled to be 10-11 during the entire reaction process, and the reaction time is maintained at 1-2 hours, so that the ferrous sulfate solution and the cyanide in the copper cyanide wastewater react with each other to generate ferrocyanide ions.

[0037] In one embodiment, the mass concentration of the ferrous sulfate solution is 10% to 25%.

[0038] It should be noted that during the binding reaction, automated equipment will be used to monitor the pH value of the solution in the reaction in real time, and when the current pH value is lower than or higher than 10~11, the reagent will be added to maintain the pH value of the controller in a stable state.

[0039] In one embodiment, the cyanide-copper wastewater contains at least free cyanide and copper-cyanide complex;

[0040] According to the stability constant of the copper-cyanide complex, the solubility product of ferrocyanate and the pH value during the corresponding reaction, the ferrous ions are first reacted with the cyanide in the copper-cyanide complex, and then reacted with the copper ions in the copper-cyanide complex, so that the cyanide is preferentially transferred and separated, and a precipitate of ferrocyanide mud is generated.

[0041] Specifically, the binding reaction that occurs under alkaline conditions is mainly based on the fact that simple cyanides formed by copper, zinc, etc. and cyanide are soluble in alkali and dissociate into cyanide in an alkaline solution. The dissociated cyanide can react with ferrous ions to produce ferrocyanide ions. The specific reaction equation is as follows:

[0042] 2Cu(CN) 3 2- + Fe 2+ + 2OH - → 2CuOH↓ + [Fe(CN)6 ] 4-

[0043] 3Zn(CN) 4 2- + 2Fe 2+ + 6OH - → 3Zn(OH) 2 ↓ + 2[Fe(CN) 6 ] 4-

[0044] Note: Among them, the stability constants of some metal cyanide complexes are:

[0045] Zn(CN) 4 2- (lgβ n =21.57);

[0046] Cu(CN) 3 2- (lgβ n =26.8);

[0047] Fe(CN) 6 4- (lgβ n =36.9).

[0048] In addition, if heavy metal cyanide complexes are added to non-oxidizing acids under non-alkaline conditions, cyanide precipitates will be precipitated:

[0049] Cu(CN) 3 2- + 2H + → 2HCN + CuCN↓

[0050] Zn(CN) 4 2- + 2H + → 2HCN + Zn(CN) 2 ↓

[0051] In summary, in this embodiment, the need to control the reaction conditions of the above-mentioned binding reaction depends on maintaining an alkaline solution environment in dynamic equilibrium.

[0052] S20, adding acid to the copper cyanide wastewater after the combination reaction, and performing a Prussian blue reaction when the pH value thereof is 4.5 to 5.5, so that the ferrous ions in the copper cyanide wastewater after the combination reaction react with the ferrocyanide ions first, and the copper in the copper cyanide wastewater after the combination reaction is freed in the solution;

[0053] It should be noted that the Prussian blue reaction specifically includes adding corresponding hydrochloric acid or FeSO4 to the copper cyanide wastewater after the combination reaction, so that the two undergo an acid precipitation reaction, thereby allowing ferrous ions to react with ferrocyanide ions in the copper cyanide wastewater, and allowing the copper ions in the copper cyanide wastewater to be free in the solution.

[0054] Among them, the specific equation involved in the Prussian blue reaction (ferrocyanide precipitation formation process) is as follows:

[0055] 6CN - + 3FeSO 4 → 3SO 4 2- + Fe 2 [Fe(CN) 6 ]↓

[0056] Fe(CN) 6 4- + 2FeSO 4 → 2SO 4 2- + Fe 2 [Fe(CN) 6 ]↓

[0057] Among them, Fe 2 [Fe(CN) 6 ]Easily oxidized by oxygen and air to Fe 4 [Fe(CN) 6 ] 3 :

[0058] 6Fe 2 [Fe(CN) 6 ] + 3O 2 + 6H 2 O → 4Fe(OH) 3 ↓ + 2Fe 4 [Fe(CN) 6 ] 3 ↓(Prussian blue)

[0059] In one embodiment, the agent used for the acid adjustment is hydrochloric acid or sulfuric acid, the mass concentration of the hydrochloric acid is 10%~30%, and the mass concentration of the sulfuric acid is 10%~40%.

[0060] S30, adding a coagulant to the solution after the Prussian blue reaction, and performing solid-liquid filtration separation to obtain ferrocyanide mud and preliminary precipitation cyanide removal wastewater, wherein the ferrocyanide mud is used as a raw material for resource recovery of hematoxylin;

[0061] In one embodiment, the coagulant aid is polyaluminium chloride and / or polyacrylamide (PAC / PAM), wherein the mass concentration of the polyaluminium chloride is 5-10%, and the mass concentration of the polyacrylamide is 0.5-1.0%.

[0062] In one embodiment, the solid-liquid filtration separation method is plate and frame filter pressing.

[0063] The mixed liquid after the reaction is filtered through a plate and frame machine (filter cloth filtration) to intercept the precipitate, and the supernatant is filtered out to enter the subsequent reaction. The intercepted precipitate is squeezed through reverse pressure filtration to form a mud cake.

[0064] S40, weakly alkali-adjusting the preliminary precipitation cyanide removal wastewater, adding hydrogen peroxide to the preliminary precipitation cyanide removal wastewater after weak alkali adjustment, using copper in the preliminary precipitation cyanide removal wastewater after weak alkali adjustment as a catalyst for oxidation reaction, and controlling the pH value of the solution during the entire oxidation reaction process to be 6.5-7.5 to remove the remaining cyanide-containing pollutants, wherein the reaction time of the oxidation reaction is 1-2 hours;

[0065] In this embodiment, the equation involved in the oxidation reaction using hydrogen peroxide and copper in cyanide copper wastewater as a catalyst is as follows:

[0066] CN - + H 2 O 2 + H 2 O → CO 3 2- + NH 4 + (Cu can be used as a reaction catalyst)

[0067] The pH value of the solution during the entire oxidation reaction process is controlled to be 6.5-7.5. This control process is the same as the above-mentioned method for controlling alkaline conditions, and both use automated equipment for dynamic balance control, which will not be repeated here.

[0068] It should be noted that in the reaction between ferrocyanide and heavy metal salts, the salts generated by ferrocyanate ions and heavy metal ions are all insoluble salts, but are soluble in alkaline solutions. The specific reaction equation is as follows:

[0069] 2Cu 2+ + Fe(CN) 6 4- → Cu 2 [Fe(CN) 6 ]↓

[0070] 2Zn 2+ + Fe(CN) 6 4- → Zn2 Fe(CN) 6 ↓

[0071] 2Fe 2+ + Fe(CN) 6 4- → Fe 2 [Fe(CN) 6 ]↓

[0072] Note: The solubility product of some ferrocyanides

[0073] Cu 2 [Fe(CN) 6 ](K sp =1.30×10 -16 );

[0074] Zn 2 [Fe(CN) 6 ](K sp =2.1×10 -16 );

[0075] Fe 4 [Fe(CN) 6 ] 3 (K sp =3.0×10 -41 ).

[0076] In one embodiment, the agent used for the weak base adjustment is NaOH, and the mass concentration is 10% to 30%.

[0077] In one embodiment, the mass concentration of the hydrogen peroxide is 7%.

[0078] S50, after the oxidation reaction is completed, adding lime for flocculation and precipitation to obtain copper mud, wherein the copper mud is subsequently processed for resource recovery.

[0079] In one embodiment, the lime component is Ca(OH)2 with a mass concentration of 10% to 20%.

[0080] In summary, refer to Figure 2 , combined with steps S10~S50, and the various reagents involved in the above examples, the overall process flow of cyanide copper wastewater treatment can be obtained. It should be noted that the process mainly lies in the following points:

[0081] 1. Prioritize the removal of cyanide and convert it into recyclable ferrocyanide mud, avoid the use of the solution of destroying cyanide and converting it into nitrogen, thereby ensuring the effective recovery and reuse of cyanide in the treatment process involved in this embodiment.

[0082] 2. Avoid using alkaline oxidation method to avoid adding a large amount of difficult-to-remove chloride ions into cyanide copper wastewater, and achieve heavy metal extraction directly from the wastewater after cyanide removal while removing cyanide.

[0083] 3. Compared with the traditional treatment process of preferentially precipitating heavy metal elements and repeatedly removing cyanide after precipitation of heavy metals, the present application only needs to execute the process once to produce ferrocyanide mud and copper mud respectively.

[0084] In addition, according to the process described above, specific examples of cyanide recovery rate and copper removal / recovery rate after treating cyanide-copper wastewater are as follows:

[0085] Project 1:

[0086] index Cyanide (mg / L) Cu (mg / L) Zn (mg / L) pH Remark Influent (raw water) 408.5 249 5.1 10.1 Ferrocyanide reaction water 18.2 Cyanide recovery rate 95.61% ＞95% Hydrogen peroxide deep oxidation water 0.095 0.137 Copper removal / recovery rate 99.94% ＞99%

[0087] Project 2:

[0088] index Cyanide (mg / L) Cu (mg / L) Zn (mg / L) pH Remark Influent (raw water) 819.2 516.3 33 8.9 Ferrocyanide reaction water 23.1 Cyanide recovery rate 97.18% ＞95% Hydrogen peroxide deep oxidation water 0.103 0.351 Copper removal / recovery rate 99.93% ＞99%

[0089] Project 3:

[0090] index Cyanide (mg / L) Cu (mg / L) Zn (mg / L) pH Remark Influent (raw water) 898.9 862 113.2 10.0 Ferrocyanide reaction water 31.7 Hydrogen peroxide deep oxidation water 0.165 0.322 Copper removal / recovery rate 99.96% ＞99%

[0091] In this embodiment, the copper cyanide wastewater is subjected to strong alkali conditioning, and a ferrous sulfate solution is added to the copper cyanide wastewater after the strong alkali conditioning to carry out a combination reaction; the copper cyanide wastewater after the combination reaction is subjected to acid conditioning, and a Prussian blue reaction is carried out; a coagulant aid is added to the solution after the Prussian blue reaction, and the solution is subjected to solid-liquid filtration separation to obtain ferrocyanide mud and preliminary precipitation decyanation wastewater; the preliminary precipitation decyanation wastewater is subjected to weak alkali conditioning, hydrogen peroxide is added to the preliminary precipitation decyanation wastewater after the weak alkali conditioning, and the copper in the preliminary precipitation decyanation wastewater after the weak alkali conditioning is used as a catalyst for an oxidation reaction to remove the residual cyanide-containing pollutants; after the oxidation reaction is completed, lime is added for flocculation and precipitation to obtain copper mud, thereby realizing a one-time process flow, preferentially reacting cyanide in the cyanide-copper wastewater with ferrous ions to generate ferrocyanide ions, and converting them into ferrocyanide mud through the Prussian blue reaction, and using the copper ions in the wastewater after subsequent cyanide removal to assist in coagulation and precipitation to obtain copper mud, thereby realizing the conversion of copper cyanide compounds in the cyanide-copper wastewater into recyclable copper resources and cyanide resources, respectively, and then realizing the recovery efficiency of various element resources in the cyanide-copper wastewater, thereby improving the resource utilization rate of the cyanide-copper wastewater.

[0092] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the method for treating and recycling copper cyanide electroplating wastewater of the present application. More simple transformations based on this technical concept are all within the scope of protection of the present application.

[0093] The treatment and resource recovery equipment for electroplating copper cyanide wastewater provided by the present application adopts the treatment and resource recovery method for electroplating copper cyanide wastewater in the above embodiment, which can solve the technical problems of treatment and resource recovery of electroplating copper cyanide wastewater. Compared with the prior art, the beneficial effects of the treatment and resource recovery equipment for electroplating copper cyanide wastewater provided by the present application are the same as the beneficial effects of the treatment and resource recovery method for electroplating copper cyanide wastewater provided by the above embodiment, and other technical features in the treatment and resource recovery equipment for electroplating copper cyanide wastewater are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0094] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0095] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

[0096] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or system including the element.

[0097] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0098] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for treating and recycling copper cyanide electroplating wastewater, characterized in that: The treatment and resource recovery method of the electrocyanide copper plating wastewater comprises the following steps: The copper cyanide wastewater is subjected to strong alkali conditioning, and a ferrous sulfate solution is added to the copper cyanide wastewater after strong alkali conditioning to carry out a binding reaction, and the pH value of the solution during the entire binding reaction process is controlled to be 10-11, so that the ferrous sulfate solution and the cyanide in the copper cyanide wastewater are subjected to a binding reaction to generate ferrocyanide ions, wherein the reaction time of the binding reaction is 1-2 hours; Acid is added to the copper cyanide wastewater after the combination reaction, and a Prussian blue reaction is performed when the pH value thereof is 4.5 to 5.5, so that the ferrous ions in the copper cyanide wastewater after the combination reaction react with the ferrocyanide ions first, and the copper in the copper cyanide wastewater after the combination reaction is freed in the solution; Adding a coagulant aid into the solution after the Prussian blue reaction, and subjecting it to solid-liquid filtration separation to obtain ferrocyanide mud and preliminary precipitation cyanide removal wastewater, wherein the ferrocyanide mud is used as a raw material for resource processing of hematoxylin; The preliminary precipitation cyanide removal wastewater is subjected to weak alkali adjustment, hydrogen peroxide is added to the preliminary precipitation cyanide removal wastewater after weak alkali adjustment, copper in the preliminary precipitation cyanide removal wastewater after weak alkali adjustment is used as a catalyst for oxidation reaction, and the pH value of the solution during the entire oxidation reaction process is controlled to be 6.5-7.5 to remove the remaining cyanide-containing pollutants, wherein the reaction time of the oxidation reaction is 1-2 hours; After the oxidation reaction is completed, lime is added for flocculation and precipitation to obtain copper mud, wherein the copper mud is subsequently processed for resource recovery.

2. The method according to claim 1, characterized in that The copper cyanide wastewater contains at least free cyanide and copper cyanide complex; According to the stability constant of the copper-cyanide complex, the solubility product of ferrocyanate and the pH value during the corresponding reaction, the ferrous ions are first reacted with the cyanide in the copper-cyanide complex, and then reacted with the copper ions in the copper-cyanide complex, so that the cyanide is preferentially transferred and separated, and a precipitate of ferrocyanide mud is generated.

3. The method according to claim 1, characterized in that The reagent used for the strong base adjustment and the weak base adjustment is NaOH, and the mass concentration is 10% to 30%.

4. The method according to claim 1, characterized in that The mass concentration of the ferrous sulfate solution is 10% to 25%.

5. The method according to claim 1, characterized in that The reagent used for the acid adjustment is hydrochloric acid or sulfuric acid, the mass concentration of the hydrochloric acid is 10%~30%, and the mass concentration of the sulfuric acid is 10%~40%.

6. The method according to claim 1, characterized in that The coagulant aid is polyaluminium chloride and / or polyacrylamide, wherein the mass concentration of the polyaluminium chloride is 5-10%, and the mass concentration of the polyacrylamide is 0.5-1.0%.

7. The method according to claim 1, characterized in that The solid-liquid filtration separation method is plate and frame filter pressing.

8. The method according to claim 1, characterized in that The mass concentration of the hydrogen peroxide is 7%.

9. The method according to claim 1, characterized in that The lime component is Ca(OH)2, and the mass concentration is 10% to 20%.

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