Comprehensive utilization method of alkaline copper-containing etching solution

Abstract

The invention relates to a comprehensive utilization method of an alkaline copper-containing etching solution. The comprehensive utilization method comprises the following steps: simultaneously feeding and mixing the alkaline copper-containing etching solution and an alkaline solution to obtain a mixed solution; mixing the mixed solution with water vapor and reacting to obtain a copper oxide suspension; performing solid-liquid separation on the copper oxide suspension to obtain copper oxide and filtrate; sequentially carrying out pH regulation and concentration treatment on the filtrate to obtain chlorine salt; according to the comprehensive utilization method, the recovery rate of copper is increased and is preferably as high as 95.0% or above, high-purity copper oxide and chlorine salt products are prepared, the purity of copper oxide is preferably as high as 83.5 wt% or above, the purity of the chlorine salt products is preferably as high as 96.5 wt% or above, efficient recycling of valuable resources in the alkaline copper-containing etching liquid is achieved, and the method is suitable for industrial production. And the operation is simple and safe, no extra defective waste is generated, and the cost is low.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of waste liquid recycling, and particularly relates to a comprehensive utilization method of alkaline copper-containing etching liquid. BACKGROUND

[0002] The alkaline copper-containing etching liquid is a chemical raw material for manufacturing electronic circuit boards, and is a kind of liquid for making electronic circuits by etching materials on copper-clad boards. During the use of the alkaline copper-containing etching liquid, the etching efficiency of the system is affected due to the enrichment of copper ions, and the system needs to be replaced. The replaced waste alkaline etching liquid usually contains 8% to 11% copper and a large amount of chlorine.

[0003] At present, the latest disposal method of the alkaline copper-containing etching liquid includes neutralization treatment with acid etching liquid to produce basic copper chloride and etching sub-liquid. For example, CN108249472A discloses a comprehensive recycling process of copper-containing etching waste liquid. The process neutralizes the acid etching liquid and the alkaline etching liquid to prepare basic copper chloride or copper sulfate, and regenerates the etching sub-liquid. However, the method needs to use ammonia gas to adjust the acid etching liquid for complete neutralization, which has a high operation risk. In addition, the etching sub-liquid product produced by the process is too limited in application industry and can only be used in the circuit board industry.

[0004] In addition, most disposal methods use neutralization to prepare copper sulfate products. For example, CN117105376A discloses a process for treating alkaline copper etching waste liquid by breaking the complex and depositing copper. The waste alkaline etching liquid is used to produce ammonium chloride and basic salt. After pretreatment, the ammonium chloride solution is used to regenerate the basic etching liquid. However, the method is complex to operate, uses risky materials such as ammonia gas, and has a complex disposal process and high disposal cost.

[0005] Therefore, it is a technical problem to be solved in the present field to provide a comprehensive utilization method of alkaline copper-containing etching liquid, which is simple to operate, harmless to the environment, maximizes the use of resources, and reduces disposal costs. SUMMARY

[0006] To solve the above technical problems, the present application provides a comprehensive utilization method of alkaline copper-containing etching liquid, which prepares high-purity copper oxide, sodium chloride and ammonium sulfate products, realizes efficient comprehensive recovery and utilization of valuable resources such as copper, sodium and ammonium in the alkaline copper-containing etching liquid, does not produce additional waste, and has a simple operation process and low cost. The method solves the problems of the prior art, such as the use of risky materials such as ammonia gas, a complex disposal process and high cost.

[0007] To achieve the above purpose, the present application adopts the following technical solutions:

[0008] The application provides a comprehensive utilization method of a basic copper-containing etching solution, and the comprehensive utilization method comprises the following steps:

[0009] (1) The basic copper-containing etching solution and the lye are simultaneously fed and mixed to obtain a mixed solution; the mixed solution is mixed with water vapor and reacts to obtain a copper oxide suspension;

[0010] (2) The copper oxide suspension obtained in step (1) is subjected to solid-liquid separation to obtain copper oxide and a filtrate; the filtrate is subjected to pH adjustment and concentration treatment in sequence to obtain a chloride salt.

[0011] The comprehensive treatment method has the advantages that: the basic copper-containing etching solution and the lye are fully mixed by means of simultaneous feeding and mixing, which is beneficial to the full reaction of the two; water vapor is used to provide heat energy for the reaction system to promote the reaction, at the same time, ammonia gas generated in the reaction is carried out of the reaction system to realize stripping, the recovery rate of copper is improved, and the purity of the obtained copper oxide and sodium chloride is improved; the recovery rate of NH4 + is improved to be used for subsequent preparation of an ammonium sulfate product, and the valuable resources such as copper, sodium and ammonium in the basic copper-containing etching solution are efficiently and comprehensively recovered and utilized.

[0012] Preferably, the total content of copper elements in the basic copper-containing etching solution in step (1) is 8-11 wt%, for example, can be 8 wt%, 8.5 wt%, 9 wt%, 9.5 wt%, 10 wt%, 10.5 wt% or 11 wt%, etc.

[0013] Preferably, the content of Cu + in the basic copper-containing etching solution in step (1) is 0.1-5 wt%, for example, can be 0.1 wt%, 0.5 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt% or 5 wt%, etc.

[0014] Preferably, the content of Cl - in the basic copper-containing etching solution in step (1) is 5-20 wt%, for example, can be 5 wt%, 8 wt%, 10 wt%, 12 wt%, 15 wt%, 18 wt% or 20 wt%, etc.

[0015] Preferably, the content of Na + in the basic copper-containing etching solution in step (1) is 1-5 wt%, for example, can be 1 wt%, 2 wt%, 3 wt%, 4 wt% or 5 wt%, etc.

[0016] Preferably, the content of NH4 +The content is 80-180 g / L, for example, it can be 80 g / L, 90 g / L, 100 g / L, 110 g / L, 120 g / L, 130 g / L, 140 g / L, 150 g / L, 160 g / L, 170 g / L or 180 g / L, etc.

[0017] Preferably, the pH of the alkaline copper-containing etching solution in step (1) is 8 to 11, for example, it can be 8, 8.5, 9, 9.5, 10, 10.5 or 11.

[0018] Preferably, the alkaline solution in step (1) includes sodium hydroxide solution and / or potassium hydroxide solution.

[0019] Preferably, the OH in the alkaline solution in step (1) - The mass concentration is 10 to 45 wt%, for example, it can be 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, or 45 wt%, etc.

[0020] Preferably, the feed flow ratio of the alkaline copper-containing etching solution to the alkaline solution in step (1) is (2-10):1, for example, it can be 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, 5.5:1, 6:1, 6.5:1, 7:1, 7.5:1, 8:1, 8.5:1, 9:1, 9.5:1 or 10:1, etc., preferably (4-6):1.

[0021] This invention further optimizes the feed flow ratio of the alkaline copper-containing etching solution to the alkali solution to (2-10):1, thereby controlling the pH of the mixed solution to 9.5-12, which is beneficial to subsequent reactions. If the feed flow ratio of the alkaline copper-containing etching solution to the alkali solution is too low, that is, the feed flow rate of the sodium hydroxide solution is too high, it will lead to excessive salt crystallization, causing pipeline blockage, and will also lead to waste of alkali solution, resulting in excessively high alkalinity of the filtrate in the next step, and increased consumption of hydrochloric acid. If the feed flow ratio of the alkaline copper-containing etching solution to the alkali solution is too high, that is, the feed flow ratio of the alkaline copper-containing etching solution to the alkali solution is too low, it will lead to a decrease in processing efficiency, i.e., production efficiency.

[0022] Preferably, the pH of the mixed solution in step (1) is 9.5 to 12, for example, it can be 9.5, 10, 10.5, 11, 11.5 or 12.

[0023] Preferably, the feed flow rate of the mixed solution in step (1) is 1.2–2 m³ / h. 3 / h, for example, could be 1.2m 3 / h, 1.4m 3 / h, 1.6m 3 / h, 1.8m 3 / h or 2m 3 / h, etc.

[0024] Preferably, the flow rate of the water vapor introduced in step (1) is 0.5-1.5m 3 / h, for example, it can be 0.5m 3 / h, 0.8m 3 / h, 1.0m 3 / h, 1.2m 3 / h, or 1.5m 3 / h, etc.

[0025] The application further preferably has the flow rate of the mixed solution introduced in step (1) being 1.2-2m 3 / h, and the flow rate of the water vapor introduced in step (1) being 0.5-1.5m 3 / h. The combination of the two increases the contact time of the mixed solution and the water vapor, so that the reaction is more complete, further improving the recovery rate of copper and NH4 + , and the purity of the copper oxide and sodium chloride products.

[0026] Preferably, the temperature of the reaction in step (1) is ≥80℃, for example, it can be 80℃, 85℃, 90℃, 95℃, or 100℃, etc., preferably 80-85℃.

[0027] Preferably, the reaction time in step (1) is 0.1-1h, for example, it can be 0.1h, 0.2h, 0.5h, 0.8h, or 1h, etc.

[0028] Preferably, the alkaline copper-containing etching solution in step (1) is first pretreated to obtain a pretreated solution, and the pretreated solution is mixed with the alkaline solution at the same time.

[0029] Preferably, the pretreatment includes mixing the alkaline copper-containing etching solution with an oxidizing agent for oxidation treatment.

[0030] Preferably, the oxidizing agent includes hydrogen peroxide and / or sodium chlorate.

[0031] Preferably, the molar ratio of the amount of the oxidizing agent added to the Cu + in the alkaline copper-containing etching solution is (0.8-1.1):1, for example, it can be 0.8:1, 0.9:1, 1:1, or 1.1:1, etc.

[0032] The application further preferably has the molar ratio of the amount of the oxidizing agent added to the Cu + in the alkaline copper-containing etching solution being (0.8-1.1):1, which is conducive to the removal of Cu +The oxidation is sufficient to provide the purity of copper oxide; if the amount of the oxidant is less, the purity of the copper oxide product will be reduced; if the amount of the oxidant is more, the purity of the copper oxide will not be obviously improved, but the reagent consumption will be increased.

[0033] Preferably, the time of the oxidation treatment is 0.5-2h, for example, it can be 0.5h, 0.8h, 1h, 1.2h, 1.5h, 1.8h or 2h, etc.

[0034] Preferably, the pH adjustment in step (2) comprises first pH adjustment and second pH adjustment in sequence.

[0035] Preferably, the end point of the first pH adjustment is that the pH of the filtrate is 1-2, for example, it can be 1, 1.2, 1.5, 1.8 or 2, etc.

[0036] The application further preferably comprises that the pH adjustment in step (2) comprises first pH adjustment and second pH adjustment in sequence, and further preferably the end point of the first pH adjustment is that the pH of the filtrate is 1-2, which ensures the color of the obtained sodium chloride product, i.e. white crystal, compared with directly adjusting the pH of the filtrate to 7-7.5.

[0037] Preferably, the adjusting solution used in the first pH adjustment comprises hydrochloric acid solution.

[0038] Preferably, the mass concentration of the hydrochloric acid solution is 1-15wt%, for example, it can be 1wt%, 3wt%, 5wt%, 8wt%, 10wt%, 12wt% or 15wt%, etc.

[0039] Preferably, the adjusting solution used in the second pH adjustment comprises carbonate solution of the metal corresponding to the obtained chlorides and / or hydroxide solution of the metal corresponding to the obtained chlorides.

[0040] Preferably, the mass concentration of the carbonate solution is 10-20wt%, for example, it can be 10wt%, 12wt%, 15wt%, 18wt% or 20wt%, etc.

[0041] Preferably, the mass concentration of the hydroxide solution is 15-45wt%, for example, it can be 15wt%, 20wt%, 25wt%, 30wt%, 35wt%, 40wt% or 45wt%, etc.

[0042] Preferably, the end point of the second pH adjustment is that the pH of the filtrate is 7-7.5, for example, it can be 7, 7.1, 7.2, 7.3, 7.4 or 7.5, etc.

[0043] Preferably, the reaction in step (1) further obtains ammonia, and the comprehensive utilization method further comprises the following steps:

[0044] (3) the ammonia gas obtained in step (1) is condensed to obtain ammonia water, and the uncondensed gas is absorbed by an acid to obtain an absorbed liquid, the ammonia water and the absorbed liquid are mixed to obtain an ammonium salt solution, and the ammonium salt solution is crystallized to obtain an ammonium salt;

[0045] Steps (2) and (3) are not in a specific order.

[0046] Preferably, the acid liquid used in the acid absorption includes sulfuric acid.

[0047] Preferably, the mass concentration of the sulfuric acid is 10-25 wt%, for example, it can be 10 wt%, 12 wt%, 15 wt%, 20 wt% or 25 wt%, etc.

[0048] Preferably, before the crystallization in step (3), the ammonium salt solution is sequentially subjected to third pH adjustment, solid-liquid separation and distillation.

[0049] Preferably, the third pH adjustment includes adjusting the pH of the ammonium salt solution to 5.5-6, for example, it can be 5.5, 5.6, 5.7, 5.8, 5.9 or 6, etc.

[0050] Preferably, the third pH adjustment uses the ammonia water obtained in step (3) or a sulfuric acid solution with a mass concentration of 40-70 wt%, for example, it can be 40 wt%, 45 wt%, 50 wt%, 55 wt%, 60 wt%, 65 wt% or 70 wt%, etc.

[0051] Preferably, the temperature of the distillation is 65-85℃, for example, it can be 65℃, 70℃, 75℃, 80℃ or 85℃, etc.

[0052] Preferably, the pressure of the distillation is -0.065 to -0.085 MPa, for example, it can be -0.065 MPa, -0.075 MPa or -0.085 MPa, etc. As a further preferred technical solution of the present application, the comprehensive utilization method of the alkaline copper-containing etching solution comprises the following steps:

[0053] (1) mixing the alkaline copper-containing etching solution with an oxidizing agent at a molar ratio of the oxidizing agent to Cu + in the alkaline copper-containing etching solution of (0.8-1.1):1, and oxidizing at 75-95℃ for 0.5-2h to obtain a pretreated solution; the pretreated solution and a lye are simultaneously fed at a feed flow ratio of (2-10):1 to obtain a mixed solution with a pH of 9.5-12; and then mixing the mixed solution with water vapor, wherein the feed flow of the mixed solution is 1.2-2m 3 / h, and the flow of the water vapor is 0.5-1.5m 3 / h; and reacting at ≥80℃ for 0.1-1h to obtain a copper oxide suspension and ammonia gas;

[0054] (2) subjecting the copper oxide suspension of step (1) to solid-liquid separation to obtain copper oxide and a filtrate; first adjusting the pH of the filtrate to 1-2 using a first pH adjusting solution, and then adjusting the pH of the filtrate to 7-7.5 using a second pH adjusting solution; and then subjecting the filtrate to concentration treatment to obtain a chloride salt;

[0055] (3) subjecting the ammonia gas of step (1) to condensation to obtain aqueous ammonia, and subjecting the uncondensed gas to acid absorption using sulfuric acid having a mass concentration of 10-25wt% to obtain an absorption liquid; and mixing the aqueous ammonia and the absorption liquid to obtain an ammonium sulfate solution, first adjusting the pH of the ammonium sulfate solution to 5.5-6 using a third pH adjusting solution, subjecting the filtrate obtained by solid-liquid separation to distillation at 65-85℃ and -0.065 to -0.085MPa, and finally subjecting the filtrate to crystallization treatment to obtain ammonium sulfate;

[0056] In step (1), the total content of copper in the basic copper-containing etching solution is 8-11wt%, the content of Cu2+ is 0.1-5wt%, the content of Cl- is 5-20wt%, the content of Na+ is 1-5wt%, the content of NH4+ is 80-180g / L, and the pH of the basic copper-containing etching solution is 8-11. + - + + - The oxidizing agent includes hydrogen peroxide and / or sodium chlorate.

[0057] In step (2), the adjusting solution used in the first pH adjustment includes a hydrochloric acid solution having a mass concentration of 1-15wt%, and the adjusting solution used in the second pH adjustment includes a carbonate solution of a metal corresponding to the chloride salt obtained and / or a hydroxide solution of a metal corresponding to the chloride salt obtained; the carbonate solution has a mass concentration of 10-20wt%, and the hydroxide solution has a mass concentration of 15-45wt%.

[0058] Preferably, the reaction in step (1) is carried out in a reactor, which includes a cylinder, a mixing component arranged at the top side of the cylinder, a feed inlet arranged on the mixing component, a discharge outlet arranged at the bottom of the cylinder, an air inlet arranged at the bottom side of the cylinder, and an air outlet arranged at the top of the cylinder; at least 3 layers of trays are arranged inside the cylinder, for example, 3 layers, 4 layers, 5 layers, 6 layers, 7 layers, 8 layers, 9 layers, or 10 layers, etc.

[0059] Preferably, the feed inlet includes a first feed inlet and a second feed inlet.

[0060] ​​​​Preferably, the barrel is internally provided with 4-8 layers of trays.

[0061] The present application effectively increases the residence time of the mixed solution and water vapor by further preferably providing the barrel with 4-8 layers of trays, so that the reaction can be more fully carried out, the recovery rate of copper and NH4 + is improved, and the purity of copper oxide and sodium chloride products is improved; if the number of trays is small, the residence time will be shortened, resulting in a decrease in the recovery rate of copper and NH4 + , and a decrease in product purity; if the number of trays is too large, the efficiency is reduced, but the effect is not significantly improved.

[0062] Preferably, the gas inlet extends into the barrel interior to form a gas inlet pipe.

[0063] Preferably, the mixing component is internally provided with a stirring member.

[0064] Preferably, the stirring member comprises a spiral structure.

[0065] Compared with the prior art, the present application has at least the following beneficial effects:

[0066] (1) The comprehensive utilization method of the alkaline copper-containing etching solution provided by the present application uses a simultaneous feeding and mixing method to fully mix the alkaline copper-containing etching solution and the alkali solution, and at the same time, uses water vapor to provide heat energy for the reaction system to promote the reaction to fully proceed, and timely carries out stripping by carrying out the ammonia gas generated in the reaction out of the reaction system, thereby achieving full utilization of copper, sodium and ammonium resources in the alkaline copper-containing etching solution, and the comprehensive utilization method is simple and safe to operate, low in cost, and no additional secondary waste is generated.

[0067] (2) The comprehensive utilization method of the alkaline copper-containing etching solution provided by the present application further optimizes the flow rate ratio of the alkaline copper-containing etching solution and the alkali solution, the flow rate of the mixed solution, and the flow rate of the water vapor, and further matches a reactor with a specific structure, thereby further improving the recovery rate of copper and NH4 + , the recovery rate of copper is preferably as high as 95.0% or more, the recovery rate of NH4 + is preferably as high as 99.0% or more, the purity of the obtained copper oxide is preferably as high as 83.5wt% or more, the purity of sodium chloride is preferably as high as 96.5wt% or more, and the purity of ammonium sulfate is preferably as high as 98.0wt% or more, thereby achieving efficient comprehensive recovery and utilization of valuable resources such as copper, sodium and ammonium in the alkaline copper-containing etching solution. BRIEF DESCRIPTION OF DRAWINGS

[0068] Figure 1 is a process flow diagram of the comprehensive utilization method of the alkaline copper-containing etching solution provided by Example 1 of the present application;

[0069] Figure 2 Figure 1 is a structural schematic diagram of a reactor used in the comprehensive utilization method of the basic copper-containing etching solution provided by Embodiment 1 of the present application;

[0070] In the figure: 1, cylinder; 2, mixing component; 3, feed inlet; 31, first feed inlet; 32, second feed inlet; 4, discharge outlet; 5, gas inlet; 6, gas outlet; 7, tray; 8, gas inlet pipe; 9, stirring component. DETAILED DESCRIPTION

[0071] The technical solutions of the present application will be further described below in combination with the accompanying drawings and through specific embodiments. However, the following examples are only simple examples of the present application and do not represent or limit the protection scope of the present application, and the protection scope of the present application is subject to the claims.

[0072] In the following examples or comparative examples, the distillation is carried out by dynamic distillation using a rotary evaporator, and the negative pressure is in the range of -0.065 to -0.085 MPa.

[0073] I. Examples

[0074] Example 1

[0075] This embodiment provides a comprehensive utilization method of a basic copper-containing etching solution, which is carried out according to the process flow shown in Figure 1, and the comprehensive utilization method comprises the following steps: Figure 1

[0076] (1) The basic copper-containing etching solution is first filtered, and then mixed with hydrogen peroxide water in a molar ratio of 1:1 of the addition amount of hydrogen peroxide water (calculated based on H2O2 in the hydrogen peroxide water) to Cu2+ in the basic copper-containing etching solution, and the mixture is subjected to oxidation treatment at 25°C for 1 h to obtain a pretreated solution. The pretreated solution and a sodium hydroxide solution (32 wt%) are simultaneously fed in a ratio of 5:1 of the feed flow rates to obtain a mixed solution with a pH of 11. The mixed solution is then mixed with water vapor, the feed flow rate of the mixed solution is 1.6 m3 / h, the flow rate of the water vapor is 1.2 m3 / h, and the reaction is carried out at 82°C for 0.3 h to obtain a copper oxide suspension and NH3. + 3 3 (2) The copper oxide suspension obtained in step (1) is subjected to pressure filtration to obtain copper oxide and a filtrate. The filtrate is first subjected to first pH adjustment to a pH of 1.5 using a hydrochloric acid solution (10 wt%), and then subjected to second pH adjustment to a pH of 7.2 using a sodium carbonate solution (15 wt%). Subsequently, sodium chloride is obtained by distillation and centrifugation in sequence.

[0077] (2) The copper oxide suspension obtained in step (1) is subjected to pressure filtration to obtain copper oxide and a filtrate. The filtrate is first subjected to first pH adjustment to a pH of 1.5 using a hydrochloric acid solution (10 wt%), and then subjected to second pH adjustment to a pH of 7.2 using a sodium carbonate solution (15 wt%). Subsequently, sodium chloride is obtained by distillation and centrifugation in sequence.

[0078] ​​​(3) The ammonia gas in step (1) is condensed to obtain ammonia water, and the uncondensed gas is acid-absorbed by sulfuric acid (15wt%) to obtain an absorbed liquid. The ammonia water and the absorbed liquid are mixed to obtain an ammonium sulfate solution, which is first adjusted to pH 5.8 by a third pH adjustment. The filtrate obtained by filtration is distilled at 75°C and finally cooled and crystallized to obtain ammonium sulfate.

[0079] In step (1), the total copper content in the alkaline copper-containing etching solution is 10 wt%, Cu + The content is 3wt%, Cl - The content is 8wt%, Na + The content is 2.5 wt%, NH4 + The content is 90g / L, and the pH of the alkaline copper-containing etching solution in step (1) is 8.6;

[0080] The reaction described in step (1) is carried out in a reactor, such as Figure 2 As shown, the reactor includes a cylindrical body 1, a mixing component 2 disposed on the top side of the cylindrical body 1, a feed inlet 3 disposed on the mixing component 2, a discharge outlet 4 disposed on the bottom of the cylindrical body 1, an air inlet 5 disposed on the bottom side of the cylindrical body 1, and an air outlet 6 disposed on the top of the cylindrical body 1; the feed inlet 3 includes a first feed inlet 31 (for feeding the alkaline copper-containing etching solution) and a second feed inlet 32 ​​(for feeding the sodium hydroxide solution); the cylindrical body 1 is provided with 5 trays 7; the air inlet 5 extends into the cylindrical body 1 through an air inlet pipe 8; the mixing component 2 is provided with a stirring element 9, which has a spiral structure.

[0081] Before step (2) in this embodiment, the filtrate is recycled to step (1) for further mixing and recycling; the distillate after distillation in step (2) is recycled to the reverse osmosis equipment for reuse.

[0082] Example 2

[0083] This embodiment provides a method for the comprehensive utilization of alkaline copper-containing etching solution, the method comprising the following steps:

[0084] (1) The alkaline copper-containing etching solution is first filtered, and then the amount of hydrogen peroxide added (calculated as H2O2 in hydrogen peroxide) is adjusted according to the amount of Cu in the alkaline copper-containing etching solution. + The alkaline copper-containing etching solution and hydrogen peroxide were mixed in a molar ratio of 0.8:1 and oxidized at 28°C for 0.5 hours to obtain a pretreatment solution. The pretreatment solution and sodium hydroxide solution (10 wt%) were simultaneously fed at a feed flow rate ratio of 4:1, and mixed to obtain a mixed solution with a pH of 12. This mixed solution was then mixed with water vapor at a feed flow rate of 1.2 m³ / h. 3 / h; and the water vapor is introduced at a flow rate of 0.5 m 3 / h; and the water vapor is introduced at a flow rate of 0.5 m

[0085] (2) The copper oxide suspension obtained in step (1) is filtered to obtain copper oxide and a filtrate; the filtrate is first adjusted to pH 1 by hydrochloric acid (15 wt%) and then adjusted to pH 7 by sodium carbonate solution (10 wt%); and sodium chloride is obtained by distillation and centrifugation in sequence;

[0086] (3) The ammonia gas obtained in step (1) is condensed to obtain aqueous ammonia, and the uncondensed gas is absorbed by sulfuric acid (10 wt%) to obtain an absorption solution; the aqueous ammonia and the absorption solution are mixed to obtain an ammonium sulfate solution, which is first adjusted to pH 5.5 by a third pH adjustment, and then filtered; the filtrate is distilled at 65°C, and finally crystallized by cooling to obtain ammonium sulfate;

[0087] In step (1), the total content of copper element in the basic copper-containing etching solution is 8 wt%, the content of Cu + is 1 wt%, the content of Cl - is 13 wt%, the content of Na + is 5 wt%, the content of NH4 + is 80 g / L, and the pH of the basic copper-containing etching solution in step (1) is 8.9.

[0088] In step (1) of the present embodiment, the reactor used for the reaction is the same as that of Example 1, except that four layers of trays are arranged inside the cylinder.

[0089] Example 3

[0090] The present embodiment provides a comprehensive utilization method of a basic copper-containing etching solution, which comprises the following steps:

[0091] (1) The basic copper-containing etching solution is first filtered, and then mixed with sodium chlorate solution (15 wt%) at a molar ratio of Cu + in the basic copper-containing etching solution to sodium chlorate of 1.1:1, and the mixture is oxidized at 26°C for 1.5 h to obtain a pretreated solution; the pretreated solution and sodium hydroxide solution (45 wt%) are simultaneously fed at a feed flow ratio of 6:1, and a mixed solution with pH 9.5 is obtained by mixing; and the mixed solution is mixed with water vapor, the feed flow rate of the mixed solution is 2 m 3 / h; the water vapor is introduced at a flow rate of 1.5 m 3 / h; and the reaction is carried out at 85°C for 0.5 h to obtain a copper oxide suspension and ammonia gas;

[0092] (2) the copper oxide suspension obtained in step (1) is filtered to obtain copper oxide and a filtrate; the filtrate is first adjusted to pH 2 using hydrochloric acid (12 wt%) and then adjusted to pH 7.5 using sodium hydroxide solution (35 wt%); and then sodium chloride is obtained by distillation and centrifugation in sequence;

[0093] (3) the ammonia obtained in step (1) is condensed to obtain ammonia water, and the uncondensed gas is absorbed by sulfuric acid (15 wt%) to obtain an absorbed solution; the ammonia water and the absorbed solution are mixed to obtain an ammonium sulfate solution, which is first adjusted to pH 6, filtered to obtain a filtrate, distilled at 85°C, and finally crystallized by cooling to obtain ammonium sulfate;

[0094] In step (1), the total content of copper in the basic copper-containing etching solution is 11 wt%, the content of Cu is 5 wt%, the content of Cl is 10 wt%, the content of Na is 2 wt%, the content of NH4 is 100 g / L, and the pH of the basic copper-containing etching solution is 9.5. + - + +

[0095] In step (1) of the present example, the reactor used for the reaction is the same as that of Example 1, except that 8 layers of trays are arranged inside the cylinder.

[0096] Example 4

[0097] The present example provides a comprehensive utilization method of a basic copper-containing etching solution, which is the same as that of Example 1, except that the feed flow rate ratio of the basic copper-containing etching solution to sodium hydroxide solution in step (1) is 2:1.

[0098] Example 5

[0099] The present example provides a comprehensive utilization method of a basic copper-containing etching solution, which is the same as that of Example 1, except that the feed flow rate ratio of the basic copper-containing etching solution to sodium hydroxide solution in step (1) is 10:1.

[0100] Example 6

[0101] The present example provides a comprehensive utilization method of a basic copper-containing etching solution, which is the same as that of Example 1, except that the flow rate of water vapor introduced in step (1) is 0.2 m 3

[0102] Example 7

[0103] ​​​​​The embodiment provides a comprehensive utilization method of a basic copper-containing etching solution, wherein, in addition to that the feeding flow of the mixed solution in step (1) is 2.5 m 3 / h, the rest are the same as those in embodiment 1.

[0104] Embodiment 8

[0105] The embodiment provides a comprehensive utilization method of a basic copper-containing etching solution, wherein, in addition to that the molar ratio of the hydrogen peroxide (calculated according to H2O2 in the hydrogen peroxide) to Cu + in the basic copper-containing etching solution is 0.5:1, the rest are the same as those in embodiment 1.

[0106] Embodiment 9

[0107] The embodiment provides a comprehensive utilization method of a basic copper-containing etching solution, wherein, in addition to that the molar ratio of the hydrogen peroxide (calculated according to H2O2 in the hydrogen peroxide) to Cu + in the basic copper-containing etching solution is 1.2:1, the rest are the same as those in embodiment 1.

[0108] Embodiment 10

[0109] The embodiment provides a comprehensive utilization method of a basic copper-containing etching solution, wherein, in addition to that step (2) is not performed with the first pH adjustment, the rest are the same as those in embodiment 1.

[0110] Embodiment 11

[0111] The embodiment provides a comprehensive utilization method of a basic copper-containing etching solution, wherein, in addition to that only three layers of trays are arranged in the inner part of the cylinder of the reactor, the rest are the same as those in embodiment 1.

[0112] Embodiment 12

[0113] The embodiment provides a comprehensive utilization method of a basic copper-containing etching solution, wherein, in addition to that only ten layers of trays are arranged in the inner part of the cylinder of the reactor, the rest are the same as those in embodiment 1.

[0114] Embodiment 13

[0115] The embodiment provides a comprehensive utilization method of a basic copper-containing etching solution, wherein, in addition to that no mixing component is arranged in the reactor, and a feeding port is directly arranged on the top side of the cylinder, the rest are the same as those in embodiment 1.

[0116] II. Comparative example

[0117] Comparative example 1

[0118] The comparative example 1 provides a comprehensive utilization method of the basic copper-containing etching solution. The comprehensive utilization method is the same as that of the example 1, except that the basic copper-containing etching solution and the sodium hydroxide solution are not fed at the same time in step (1), but the basic copper-containing etching solution is first fed, and then the sodium hydroxide solution is added to the basic copper-containing etching solution.

[0119] Comparative example 2

[0120] The comparative example 1 provides a comprehensive utilization method of the basic copper-containing etching solution. The comprehensive utilization method is the same as that of the example 1, except that the basic copper-containing etching solution and the sodium hydroxide solution are not fed at the same time in step (1), but the basic copper-containing etching solution is first fed, and then the sodium hydroxide solution is added to the basic copper-containing etching solution.

[0121] III. Test and results

[0122] The purity of the copper oxide, sodium chloride and ammonium sulfate product obtained in the above examples or comparative examples is tested, and the recovery rate of copper and the recovery rate of NH4 + are calculated, respectively, and the results are shown in Table 1.

[0123] Table 1

[0124]

[0125]

[0126] In Table 1, “-” represents no relevant data.

[0127] From the data in Table 1, it can be seen that:

[0128] (1) From the comprehensive examples 1 to 3, it can be seen that the comprehensive utilization method of the basic copper-containing etching solution provided by the present application, by adopting the simultaneous feeding and mixing method, combining the control of the feeding ratio of each raw material, using water vapor to provide heat energy while carrying ammonia gas to realize stripping, and matching the reactor with a specific structure, the copper oxide product with a purity of 83.5wt% or higher, the sodium chloride product with a purity of 96.5wt% or higher, and the ammonium sulfate with a purity of 98.0wt% or higher are prepared, and the recovery rate of copper is as high as 95.0% or higher, and the recovery rate of NH4 + is as high as 99.0% or higher, realizing the efficient recovery and utilization of valuable resources in the basic copper-containing etching solution.

[0129] (2) From the comprehensive examples 1 and examples 4 and 5, it can be seen that by further optimizing the feeding flow ratio of the basic copper-containing etching solution and the lye in step (1) to be (4-6): 1, and adjusting the pH of the mixed solution to be 9.5-12, the reaction is more complete, the recovery rate of copper is improved, and the purity of the obtained copper oxide and sodium chloride is further improved.

[0130] (3) Combining Examples 1, 6, and 7, it can be seen that the steam flow rate in Example 6 was too low, resulting in the reaction system temperature not being able to rise sufficiently above 80°C, leading to incomplete reaction and the reaction of copper and NH4. + The recovery rate decreased, and the purity of each product declined. In Example 7, the feed flow rate of the mixed solution was too high, resulting in a shortened contact time between water vapor and the mixed solution, leading to insufficient heating and thus incomplete reaction. Copper and NH4... + The recovery rate decreases, and the purity of each product decreases; this indicates that the present invention further optimizes the feed flow rate of the mixed solution in step (1) to 1.2-2 m³ / h. 3 / h; and further preferably, the steam flow rate is 0.5–1.5 m³ / h. 3 / h, further increasing copper and NH4 + While ensuring the recovery rate and product purity, it avoids the problems of increased energy consumption caused by excessively high water vapor flow rate and decreased processing efficiency and increased time costs caused by excessively low feed flow rate of the mixed solution.

[0131] (4) As can be seen from the combined examples 1 and 8 to 10, the amount of hydrogen peroxide added in example 8 was too low, resulting in residual Cu in the alkaline copper-containing etching solution. + This leads to a decrease in copper recovery rate; the amount of hydrogen peroxide added in Example 9 is too high, which does not significantly improve the purity of copper oxide, but instead increases reagent consumption, causing waste and increasing operational risks; in Example 10, the properties of the sodium chloride product change because the first pH adjustment is not performed in step (2); this indicates that the present invention further optimizes the amount of oxidant added and the amount of Cu in the alkaline copper-containing etching solution. + The molar ratio is (0.8~1.1):1, or more preferably, the pH adjustment in step (2) includes a first pH adjustment and a second pH adjustment, which further improves the quality of the obtained copper oxide product or sodium chloride product.

[0132] (5) As can be seen from the combined examples 1 and 11 to 13, the comprehensive utilization method of the present invention, by further combining a reactor with a specific structure, that is, further selecting the internal structure of the cylinder to be provided with 4 to 8 layers of trays, further providing a mixing component on the top side of the cylinder, further ensuring that the alkaline copper-containing etching solution is fully mixed with the alkaline solution, further increasing the contact time between the mixed solution and the water vapor, and improving the efficiency of copper and NH4. + This improves the recovery rate and purity of copper oxide and sodium chloride products, while reducing energy consumption.

[0133] (6)It can be seen from the combination of example 1 and comparative examples 1 and 2 that, since the basic copper-containing etching solution and the sodium hydroxide solution in comparative example 1 are not fed at the same time, but the basic copper-containing etching solution is fed first, and then the sodium hydroxide solution is added to the basic copper-containing etching solution, which leads to insufficient mixing of the two, resulting in a decrease in the recovery rate of copper and NH4 + , and a decrease in the purity of the copper oxide and sodium chloride products; since the mixed solution in comparative example 2 is not mixed with water vapor, but the mixed solution is directly heated to 82℃ for reaction, not only the energy consumption is increased, but also the free ammonia produced in the reaction cannot or cannot be removed from the reaction system in time, and is dissolved back into the reaction system, resulting in a decrease in the purity of the copper oxide and sodium chloride, and almost no recovery of NH4 + ; thus it is shown that, by selecting the simultaneous feeding and mixing mode, and by using water vapor to provide heat energy at the same time, ammonia gas is carried out of the reaction system in time to achieve stripping, high-purity copper oxide and sodium chloride products are obtained, the recovery rate of ammonium is improved, and efficient comprehensive recovery and utilization of valuable resources in the basic copper-containing etching solution is achieved.

[0134] The applicant declares that the above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and those skilled in the art should understand that any changes or replacements within the technical scope disclosed by the present application can be easily thought of by any person skilled in the art in the technical field, and all of them fall within the protection scope and disclosure scope of the present application.

Claims

1. A comprehensive utilization method of a basic copper-containing etching solution, characterized by, The comprehensive utilization method comprises the following steps: (1) the alkaline copper-containing etching solution and the lye are simultaneously fed and mixed to obtain a mixed solution; the mixed solution is mixed with water vapor and reacted to obtain a copper oxide suspension; (2) the copper oxide suspension in step (1) is subjected to solid-liquid separation to obtain copper oxide and a filtrate; the filtrate is sequentially subjected to pH adjustment and concentration treatment to obtain a chloride salt.

2. The integrated utilization method according to claim 1, characterized by, The total content of copper element in the alkaline copper-containing etching solution in step (1) is 8-11 wt%; Preferably, the content of Cu in the basic copper-containing etching solution in step (1) is 0.1-5 wt%. + Preferably, the content of Cu in the basic copper-containing etching solution in step (1) is 0.1-5 wt%. Preferably, the content of Cl in the basic copper-containing etching solution in step (1) is 5-20 wt%. - Preferably, the content of Cl in the basic copper-containing etching solution in step (1) is 5-20 wt%. Preferably, the content of NH4 + 80-180 g / L; Preferably, the pH of the alkaline copper-containing etching solution in step (1) is 8-11; Preferably, the lye in step (1) comprises a sodium hydroxide solution and / or a potassium hydroxide solution, preferably a sodium hydroxide solution; Preferably, the mass concentration of OH - in the alkaline solution in step (1) is 10-45 wt%.

3. The comprehensive utilization method according to claim 1 or 2, characterized by, The feeding flow rate ratio of the alkaline copper-containing etching solution to the lye in step (1) is (2-10):1, preferably (4-6):1; Preferably, the pH of the mixed solution in step (1) is 9.5-12.

4. The integrated utilization method according to any one of claims 1 to 3, characterized by, The feed flow rate of the mixed solution in step (1) is 1.2 to 2 m 3 / h. Preferably, the water vapor is introduced at a flow rate of 0.5 to 1.5 m 3 / h.

5. The integrated utilization method according to any one of claims 1 to 4, characterized by, The temperature of the reaction in step (1) is ≥80°C, preferably 80-85°C; Preferably, the reaction time in step (1) is 0.1-1 h.

6. The integrated utilization method according to any one of claims 1 to 5, characterized by, The alkaline copper-containing etching solution in step (1) is first subjected to pretreatment to obtain a pretreated solution, and the pretreated solution is then simultaneously fed and mixed with the lye; Preferably, the pretreatment comprises mixing the alkaline copper-containing etching solution with an oxidizing agent for oxidation treatment; Preferably, the oxidizing agent comprises hydrogen peroxide and / or sodium chlorate; preferably, the oxidizing agent is added in an amount of (0.8-1.1): 1 molar ratio with respect to Cu + in the basic copper-containing etching solution.

7. The integrated utilization method according to any one of claims 1 to 6, characterized by, The pH adjustment in step (2) comprises first pH adjustment and second pH adjustment in sequence; Preferably, the end point of the first pH adjustment is that the pH of the filtrate is 1-2; Preferably, the end point of the second pH adjustment is that the pH of the filtrate is 7-7.

5.

8. The integrated utilization method according to any one of claims 1 to 7, characterized by, Ammonia gas is also obtained after the reaction in step (1), and the comprehensive utilization method further comprises the following step: (3) the ammonia gas in step (1) is condensed to obtain aqueous ammonia, and the uncondensed gas is subjected to acid absorption to obtain an absorbed solution, and the aqueous ammonia and the absorbed solution are mixed to obtain an ammonium salt solution, which is subjected to crystallization treatment to obtain an ammonium salt; Steps (2) and (3) are not in a specific order; Preferably, before the crystallization in step (3), the ammonium salt solution is sequentially subjected to third pH adjustment and distillation.

9. The integrated utilization method according to any one of claims 1 to 8, characterized by, The reaction in step (1) is carried out in a reactor, and the reactor comprises a cylinder, a mixing component arranged at the top side of the cylinder, a feeding port arranged on the mixing component, a discharging port arranged at the bottom of the cylinder, an air inlet arranged at the bottom side of the cylinder, and an air outlet arranged at the top of the cylinder; at least 3 layers of trays are arranged inside the cylinder.

10. The integrated utilization method according to claim 9, characterized by, 4-8 layers of trays are arranged inside the cylinder; Preferably, the air inlet extends into an air inlet pipe inside the cylinder; Preferably, the mixing component is internally provided with a stirring member; Preferably, the stirring member comprises a spiral structure.

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