WO2019007407A1 - Ammonia-stilling recycling process for alkaline waste etching solution of printed circuit board, and system thereof - Google Patents

Abstract

An ammonia-stilling recycling process for an alkaline waste etching solution of a printed circuit board, comprising: heating an alkaline waste etching solution, and collecting gas generated in the course of heating so as to obtain waste solution gas; obtaining a solid-liquid mixture A1 after the alkaline waste etching solution is heated till a precipitate is separated out; mixing the solid-liquid mixture A1 with hydrochloric acid and/or an acidic waste etching solution, adjusting the pH value, and separating an insoluble precipitate from other soluble components so as to obtain a mixed solution A2; mixing the waste solution gas with carbon dioxide so as to generate ammonium carbonate and/or ammonium bicarbonate; and adding ammonium carbonate and/or ammonium bicarbonate to the mixed solution A2 and supplementing other required components for an etching process so as to obtain a recycling etching sub-solution. No foreign substances which is harmful to the etching operation can be brought into the treating process, the recycling effect can be achieved, and the production costs can be effectively reduced. Moreover, the problem about ammonia nitrogen pollution caused during a conventional alkaline ammonium cupric chloride extracting and recovering process can be solved. Also disclosed is an ammonia-stilling recycling system for an alkaline waste etching solution of a printed circuit board.

Description

Steam ammonia recovery cycle process and system for circuit board alkaline etching waste liquid Technical field

The invention relates to the field of recycling and recycling of etching waste liquid, in particular to a process of recycling ammonia distillation of a circuit board alkaline etching waste liquid.

Background technique

Etching is an important step in the fabrication of existing printed circuit boards (PCBs). Etching refers to removing the unnecessary copper etching liquid on the copper clad substrate by chemical reaction to form a desired circuit pattern.

Currently commonly used etching solutions are acidic copper chloride and alkaline copper ammonium chloride, of which:

The main components of the acidic copper chloride etching solution are: copper salt, hydrochloric acid, sodium chloride or ammonium chloride, water, and optional additives.

The main components of the alkaline copper ammonium chloride etching solution are copper salts, ammonium chloride, ammonia water, water, optional carbonates, and optional additives; among them, the carbonates are usually ammonium carbonate and ammonium hydrogencarbonate. When the PCB board is etched using an alkaline copper chloride ammonium etching solution, the concentration of each component in the etching process is usually maintained by adding an etching solution. The main components of the etchant liquid are ammonium chloride, ammonia, water, optional carbonates, and optional additives.

The optional additives in the etching solution and the etching solution refer to some non-essential, but optimized effects on the performance of the etching solution (such as changing the reaction equilibrium, reaction rate) without changing the main chemical reaction occurring in the etching process. Auxiliary. For example, stabilizers, speed increasing agents, and the like.

When etching with alkaline copper ammonium chloride, the following reaction occurs:

Cu(NH ₃ ) ₄ Cl ₂ +Cu→2Cu(NH ₃ ) ₂ Cl

4Cu(NH ₃ ) ₂ Cl+4NH ₄ Cl+4NH ₄ OH+O ₂ →4Cu(NH ₃ ) ₄ Cl ₂ +6H ₂ O

Since the alkaline copper ammonium chloride etching solution continuously reacts during the etching process, the components of the etching liquid are continuously consumed and the concentration is constantly changed. Generally, the composition content of the etching liquid liquid is slightly higher than the corresponding content in the etching liquid. concentration. During the etching process, the concentration of copper ions needs to be controlled at 30-180 g/l, and the pH is within 7-9. Therefore, it is necessary to continuously detect the content of the components in the etching solution by an automatic inspection feeding control machine during the production process and according to In the case of detection, an etchant liquid and/or an ammonia solution may be added.

In actual production, in order to keep the composition of the etching liquid stable, it is necessary to continuously add an etching liquid and/or a supplementary ammonia water, which inevitably leads to an increase in the etching liquid in the etching bath and overflows outside the groove; etching outside the etching groove The liquid or the used etching liquid is generally referred to as an etching waste liquid, and the main components of the alkaline copper chloride ammonium etching waste liquid include copper ammonium chloride, ammonium copper chloride, ammonium chloride, ammonia water, Some alkaline etching waste liquids also contain ammonium carbonate, ammonium hydrogencarbonate, organic ammonium salts, organic amines and the like.

At present, there are three common treatment methods for alkaline etching waste liquid:

Acidification electrolysis method: the alkaline etching waste liquid is acidified by hydrochloric acid and/or acidic copper chloride etching waste liquid to produce a precipitate and a supernatant liquid; the separated precipitate is dissolved in sulfuric acid to prepare copper sulfate or electrolytically. The copper sulfate-containing residual liquid produced in the process of preparing the refined copper, the supernatant liquid and the copper sulfate is further removed by copper and then concentrated by evaporation to obtain a mixed ammonium salt. Among them, the main components of the existing acidic copper chloride etching waste liquid generally contain hydrochloric acid, copper chloride, cuprous chloride, and water.

The disadvantage of this method is that sulfuric acid is used in the recycling process, and sulfate which is attacking and corrosive to the etching resist is introduced, so that the mixed ammonium salt produced can no longer be reused in the etching process; The application of the evaporation concentration process to obtain mixed ammonium salts consumes a large amount of energy.

Alkalinization method: a sodium hydroxide solution is added to the alkaline etching waste liquid, and heated to obtain a copper oxide precipitate. Then, the copper oxide precipitate is dissolved in sulfuric acid to obtain copper sulfate, and the ammonia gas escaping during the heating process is absorbed by water to obtain ammonia water for recycling. The remaining liquid also needs to be treated to meet emission standards before it can be discharged.

The drawback of this method is that after the recovery of copper oxide and ammonia water, the wastewater treatment volume is large and the treatment cost is high.

Extraction electrolysis method: the alkaline etching waste liquid is mixed with the organic extracting agent, and then subjected to back extraction using sulfuric acid to obtain copper sulfate, and the copper sulfate solution is electrolyzed to obtain refined copper. Part of the waste liquid after phase separation treatment can be re-allocated as an etchant liquid for recycling.

The organic extractant is used in the recovery process of the method. The disadvantage of the method is that when the etching liquid is recycled and reused, the etching liquid is mixed with a small amount of organic extracting agent, which accumulates the etching rate and quality. The indicator has fallen. In addition, the use of the extractant process leads to ammonia nitrogen contamination during the recovery process, and its processing cost is also relatively high.

Ammonia nitrogen pollutants are very soluble in water, and the ammonia nitrogen content index in water is an important indicator of water eutrophication. Once eutrophication, water bodies can easily cause algae to multiply in the water to burst red tides and blooms. The oxygen content is reduced, causing the remaining organisms (fish, shrimps, crabs, etc.) to die in the absence of oxygen, resulting in water pollution; on the other hand, the accumulation of toxins produced by toxic algae can directly lead to water pollution.

In summary, the existing three methods for treating alkaline etching waste liquid can recover copper sulfate or refined copper or ammonium salt or ammonia water from waste liquid, and some can re-allocate alkaline etching waste liquid into an etchant. Liquid recycling, but in the process of circulating the alkaline etching waste liquid, it may bring in foreign substances that are poorly etched, affect the etch rate and quality index, and bring about ammonia nitrogen pollution, or high processing cost. There is no treatment method that can recycle and reuse the alkaline etching waste liquid well, and can effectively reduce the production cost. At the same time, it can also solve the ammonia nitrogen pollution brought by the traditional alkaline copper chloride ammonium extraction electrolysis recovery process. problem.

Summary of the invention

The object of the present invention is to provide a vaporized ammonia recovery cycle process for an alkaline etching waste liquid of a circuit board, which not only can recycle and recycle the alkaline etching waste liquid, but also can maintain the recycled recycled etchant liquid. Normal etch rate and quality specifications; and no ammonia nitrogen contamination problems.

The object of the present invention can be achieved by the following technical solutions:

A steam ammonia recovery cycle process for alkaline etching waste liquid of a circuit board, comprising the following steps:

(1) Gas-liquid separation of etching waste liquid: heating an alkaline etching waste liquid having a copper ion concentration of 30-180 g/L and a pH value of 7-9, collecting gas generated during heating, and evaporating the waste liquid Gas A; when the etching waste liquid is heated until a precipitate is precipitated, a solid-liquid mixture A1 is obtained;

(2) Adjustment of pH value: mixing the solid-liquid mixture A1 obtained in the step (1) with hydrochloric acid and/or acid etching waste liquid and adjusting the pH to 3-6 to further increase the precipitate in the solid-liquid mixture A1, The precipitate in the obtained solid-liquid mixture A1 is separated, and after solid-liquid separation, a solid precipitate and a mixed solution A2 are respectively obtained;

(3) treatment of the gas: the waste liquid collected in the step (1) is distilled off and the gas A is mixed with carbon dioxide to form ammonium carbonate and/or ammonium hydrogencarbonate;

(4) mixing of the solution: adding ammonium carbonate and / or ammonium bicarbonate to the mixed solution A2 obtained in step 2, to obtain a mixed solution A3;

(5) Regeneration of the etching solution: The other desired components of the etching process are supplemented in the mixed solution A3 obtained in the step (4), and the etching liquid is recycled.

In the heating process of the step (1) according to the present invention, the generated gas includes ammonia gas, water vapor and carbon dioxide which may be generated; wherein the ammonia gas is derived from the evaporation of ammonia water contained in the etching waste liquid and a part of the alkaline etching liquid. Decomposition or hydrolysis reaction of components such as ammonium carbonate, ammonium hydrogencarbonate, organic amines, and organic ammonium. The carbon dioxide is derived from the thermal decomposition reaction of ammonium carbonate and/or ammonium hydrogencarbonate contained in the etching waste liquid; the water vapor is derived from evaporation of liquid water;

See the following chemical reaction formula for details.

The chemical reaction occurring in step (1) is as follows:

Volatilization of ammonia: NH ₄ OH→H ₂ O+NH ₃ ↑

Thermal decomposition reaction of ammonium carbonate: (NH ₄ ) ₂ CO ₃ → 2NH ₃ ↑ + CO ₂ + H ₂ O

Thermal decomposition reaction of ammonium bicarbonate: NH ₄ HCO ₃ →NH ₃ ↑+CO ₂ +H ₂ O

Thermal decomposition reaction of organic ammonium salt: R-NH ₄ →NH ₃ ↑+RH

Thermal hydrolysis of organic amines: R-NH ₂ +H ₂ O→NH ₃ ↑+R-OH

The main components of the solid-liquid mixture A1 in the step (1) according to the present invention include copper ammonium chloride, cuprous ammonium chloride, ammonium chloride, ammonia water, basic copper chloride, and copper hydroxide. Among them, ammonium copper chloride, ammonium hexachloride, ammonium chloride and ammonia are the main components of alkaline etching waste liquid. The source of basic copper chloride and copper hydroxide is because copper chloride is only acidic. It is soluble, and when it becomes neutral or alkaline, it becomes basic copper chloride Cu ₂ (OH) ₂ Cl ₂ and/or copper hydroxide Cu(OH) ₂ and is insoluble. Water, while the nitrogen atom of ammonia has a lone pair of electrons, which can form hydrogen bonds with water molecules, so copper and copper chloride of copper chloride form a complex of copper chloride ammonia Cu(NH ₃ ) ₄ Cl ₂ , soluble in In the water. Therefore, in the step 1, since part of the ammonia gas and a part of water in the solution are evaporated as one of the components of the gas A, there is not enough ammonia and copper chloride complex in the solution, and at the same time, the water as a solvent is reduced, thereby A precipitate of basic copper chloride and/or copper hydroxide appears to obtain a solid-liquid mixture A1:

2Cu(NH ₃ ) ₄ Cl ₂ +2H ₂ O→Cu ₂ (OH) ₂ Cl ₂ +2NH ₄ Cl+6NH ₃ ↑

Cu(NH ₃ ) ₄ Cl ₂ +2H ₂ O→Cu(OH) ₂ +2NH ₄ Cl+2NH ₃ ↑

The main chemical equation for the reaction of the solid-liquid mixture A1 with hydrochloric acid in the step (2) of the present invention is as follows:

2Cu(NH ₃ ) ₄ Cl ₂ +2HCl+2H ₂ O→Cu ₂ (OH) ₂ Cl ₂ ↓+4NH ₄ Cl

4Cu(NH ₃ ) ₂ Cl+8HCl+4H ₂ O+O ₂ →2Cu ₂ (OH) ₂ Cl ₂ ↓+8NH ₄ Cl+2H ₂ O

2Cu(OH) ₂ +2HCl→Cu ₂ (OH) ₂ Cl ₂ ↓+2H ₂ O

NH ₄ OH+HCl→NH ₄ Cl+H2O

Cu ₂ (OH) ₂ Cl ₂ +4HCl→2CuCl ₂ +4H ₂ O

It can be seen from the above reaction formula that when the solid-liquid mixture A1 is reacted with hydrochloric acid, the main component of the mixed solution A2 described in the step (2) is ammonium chloride and water, and may additionally contain chlorine formed by reaction with sufficient hydrochloric acid. Copper and residual unreacted ammonium copper chloride, cuprous ammonium chloride, hydrochloric acid.

In the step (2), if the solid-liquid mixture A1 is only reacted with the acidic etching waste liquid, the acidic etching waste liquid is the waste liquid generated after the etching operation of the acidic copper chloride etching liquid, and the main components thereof are hydrochloric acid and chlorine. Copper, cuprous chloride, water, therefore, in addition to the reaction of the copper chloride ammonium, cuprous ammonium chloride, ammonia water and copper hydroxide in the above-mentioned solid-liquid mixture A1 with hydrochloric acid in the acid etching waste liquid In addition, the following reactions will occur:

Cu(OH) ₂ +CuCl ₂ →Cu ₂ (OH) ₂ Cl ₂ ↓

4NH ₄ OH+CuCl ₂ →Cu(NH ₃ ) ₄ Cl ₂ +4H ₂ O

Cu ₂ Cl ₂ +4NH ₄ OH→2Cu(NH ₃ ) ₂ Cl+4H ₂ O

Therefore, when the solid-liquid mixture A1 is reacted with the acidic etching waste liquid, the mixed solution A2 described in the step (2) is mainly composed of ammonium chloride and water, and may contain copper chloride ammonia, cuprous chloride ammonia, chlorine. Copper, cuprous chloride and hydrochloric acid.

The solid precipitate separated in the step (2) is mainly composed of basic copper chloride and/or copper hydroxide, and may also contain ammonium chloride which is not dissolved due to insufficient water in the solid-liquid mixture A1, and can be washed to become a basic type. Copper chloride and/or copper hydroxide are packaged for sale, and can also be sold by heating with a sodium hydroxide solution to form a copper oxide product.

In the step (3) of the present invention, the ammonia gas in the gas reacts with carbon dioxide and water vapor as follows:

2NH ₃ +CO ₂ +H ₂ O→(NH ₄ ) ₂ CO ₃

NH ₃ +CO ₂ +H ₂ O→NH ₄ HCO ₃

The carbon dioxide in the step (3) according to the present invention may be the thermally decomposed ammonium carbonate or ammonium hydrogencarbonate derived from the etching waste liquid of the step (1), or may be an added carbon dioxide gas, or both. combination.

The ammonium carbonate and/or ammonium hydrogencarbonate added in A2 in the step (4) of the present invention may be purchased ammonium carbonate and/or ammonium hydrogencarbonate, or may be derived from the step (3). Ammonium carbonate, ammonium hydrogencarbonate, or a combination of the two; the main component of the obtained mixed solution A3 is: copper ammonium chloride, cuprous ammonium chloride, ammonium chloride, ammonium carbonate and/or ammonium hydrogencarbonate.

The invention utilizes the characteristics of ammonium carbonate and ammonium hydrogencarbonate thermally decomposed to form ammonia, and ammonium carbonate and/or ammonium hydrogencarbonate is used as an etched NH ₄ ⁺ source, preferably from the ammonium carbonate and ammonium hydrogencarbonate obtained in the step (3). Dissolving it in the mixed solution A2 to prepare a recycled reuse etchant liquid can effectively provide the NH ₄ ⁺ component during the etching process, reducing the amount of additional ammonia added. Therefore, it is ensured that the volume of the recycled etching solution obtained after the recycling process of the present invention is not larger than the amount of the etching seed liquid added for the etching production, so that the recycled etching liquid residue is not generated during the recycling process. Too many problems that cannot be consumed.

The other required components of the supplementary etching process in the mixed solution A3 of the step (5) of the present invention means that the original etching liquid is contained, but is consumed by the reaction during the etching process, and there is no regeneration or regeneration amount in the recycling process. Insufficient ammonium chloride, ammonia, water, optional carbonates, and optional additives to minimize the ammonium ion concentration, ammonium chloride concentration, and optional additive concentration of the recycled etchant solution Ammonium ion concentration, ammonium chloride concentration and optional additive concentration in the etching solution when etching the waste liquid recovery system; wherein the supplemented ammonia water may be replaced by ammonium carbonate and/or ammonium hydrogencarbonate as long as the NH ⁴⁺ ion concentration is maintained Quite enough.

The replenishing amount of other required components of the etching process in the step (5) of the present invention can be determined by detecting the ammonium ion concentration, the ammonium chloride concentration and the optional additive concentration, or can be determined based on empirical data.

In the step (5) of the present invention, the recycled etchant liquid may partially replace or completely replace the etching liquid prepared by using the raw material, and is replenished in the etching liquid during the etching operation to form an etch liquid for recycling. Can greatly reduce the cost of etching production. The addition of the etching solution in the production process is to automatically detect the pH value and/or the specific gravity parameter value of the etching liquid through the automatic detection and feeding control machine on the production line, and automatically control the addition of the etching liquid to the etching liquid according to the set value. .

The present invention can make the following further improvements:

In order to better recycle the etching waste liquid, when the mixed solution A2 is used in the step (4) to dissolve the ammonium carbonate and/or ammonium hydrogencarbonate obtained in the step (3), the mixing of the step (2) can be directly carried out. Solution A2 is washed with ammonium carbonate and/or ammonium hydrogencarbonate, that is, the production container of ammonium carbonate and/or ammonium hydrogencarbonate is directly washed with the mixed solution A2, ammonium carbonate and/or ammonium hydrogencarbonate is taken away, and then step (5) is carried out. .

From the ammonia gas and carbon dioxide reaction equations, when the concentration of carbon dioxide is lower than the concentration of ammonia, the reaction equilibrium tends to produce ammonium carbonate; conversely, the equilibrium of the reaction tends to produce ammonium bicarbonate; The amount of concentration ratio can control the amount of ammonium carbonate and ammonium hydrogencarbonate obtained. Therefore, in the step (3), the gas reaction can be divided into the following two parts: (1) the first portion of the ammonia gas substance concentration is greater than the carbon dioxide material concentration, and the second portion of the ammonia gas material concentration is less than the carbon dioxide The amount of substance in order to control the ratio of ammonium carbonate and ammonium bicarbonate formed. That is, the gas may first be subjected to a reaction in which the concentration of the ammonia gas substance is greater than the concentration of the carbon dioxide material, and then the amount of the unreacted gas remaining in the ammonia gas is less than the concentration of the carbon dioxide material; or it may be Directly diverting the gas into two parts, respectively performing a reaction in which the concentration of the ammonia substance is greater than the concentration of the carbon dioxide substance and the concentration of the substance of the ammonia gas is less than the concentration of the carbon dioxide substance. Ammonium carbonate contributes to the etching process. The etching is stable, and ammonium bicarbonate is advantageous for compounding the outlet of the reaction tank to reduce the pollution caused by the ammonia exhaust gas.

In order to better recycle the etching waste liquid, in the step (3), the tail gas collection reaction of the ammonium carbonate and/or ammonium hydrogencarbonate synthesis reaction may adopt a jet device, and the liquid absorption liquid gas using the water as the jet reacts with the carbon dioxide to generate The tail gas of the synthesis reaction of ammonium carbonate and/or ammonium hydrogencarbonate, and the aqueous solution of ammonium carbonate and/or ammonium hydrogencarbonate recovered in the fluidic device can be reused for the preparation of the etching solution.

In order to better recycle the etching waste liquid, in the step (3), the liquid of the ammonium carbonate and/or ammonium hydrogencarbonate synthesis reaction is absorbed by the liquid using the water jet as the jet device, and the aqueous solution is obtained by using a pH meter. The aqueous solution obtained in the fluidic device is subjected to pH detection; when it is detected that the aqueous solution is alkaline, the amount of carbon dioxide in the ammonium carbonate and/or ammonium hydrogencarbonate synthesis reaction is appropriately increased; otherwise, the amount of carbon dioxide is appropriately reduced.

In order to promote the escape of gas from the stirring position, it is easy to collect. In the step (1), a stirring device can be used in the heating process.

In order to accelerate the gas-liquid separation of the etching waste liquid of the step (1), an external pressurized air cannula is provided on the heating vessel, and is opened during the heating process and/or after the heating process is completed. The external pressurized air cannula includes a conduit and a pump that communicate the heating vessel with the outside.

The external pressurized air cannula is opened during the heating process, and the air outside the heating container can be driven into the heating container through the external pressurized air cannula, and the alkaline etching waste liquid in the heating container is stirred to promote the evaporation of the waste liquid. The gas, and the volatilized gas is quickly introduced into the step (3) for the synthesis reaction.

After the heating process is completed, the external pressurized air cannula is opened, and the air outside the heating container can be driven into the heating container through the external pressurized air cannula to accelerate the temperature of the mixture in the heating container while stirring. So as soon as possible to the next step.

Preferably, in the heating of the etching waste liquid of the step (1), the heating temperature may range from 30 ° C to the boiling temperature of the waste liquid.

The second object of the present invention can be solved by the following technical solutions:

A system for a vaporized ammonia recovery cycle of a circuit board alkaline etching waste liquid, comprising the following components:

At least one acid-base adjusting tank for adjusting the pH value of the remaining liquid after evaporation of the alkaline etching waste liquid;

At least one heating evaporation tank, which is composed of a heating tank body, a heating device and an air outlet disposed inside and/or outside the heating tank body; and is used for concentrating and heating the alkaline etching waste liquid and separating the waste liquid gas;

At least one compounding reaction tank, which is composed of a reaction tank body and a carbon dioxide inlet and a waste gas inlet provided thereon; the carbon dioxide inlet is connected to a carbon dioxide source, and the waste gas inlet is connected to an outlet of the heating evaporation tank For the manufacture of ammonium carbonate and / or ammonium bicarbonate;

At least one filter for separating solids and liquids in the solid-liquid mixture, the inlet of the filter being connected to the acid-base adjusting tank, and the liquid outlet of the filter is connected to the sub-liquid mixing tank or the compounding reaction tank;

At least one sub-liquid mixing tank for preparing a recirculating etchant liquid.

The present invention can also make the following improvements:

A stirring device is disposed in the heating evaporation tank to agitate the heated alkaline etching waste liquid to promote the gas to escape from the stirring position.

An external pressurized air cannula is disposed in the heating evaporation tank, and the external pressurized air cannula is composed of a pipe and a pump that communicate with the outside of the heating evaporation tank to pump air into the alkaline etching waste liquid. Stirring it, causing the waste liquid to volatilize the gas, and allowing the volatilized gas to quickly enter step (3) for the synthesis reaction.

Preferably, the pump is connected to the pipe connecting the heating evaporation tank to the compounding reaction tank, and/or the gas outlet of the compounding reaction tank is provided.

The present invention may also provide additional gas outlets and/or additional liquid inlets and/or discharge ports on the compounding reaction tank. One of the functions of the additional gas outlet is to serve as an outlet for the gas when the compounding reaction tank is connected to other chemical reaction tanks or jet devices; another function is to effectively prevent the gas pressure in the reaction tank from being excessively large, thereby posing a safety hazard. . The additional liquid inlet is used for the inlet of the mixed solution A2 after passing through the filter into the chemical reaction tank. In addition, when the ammonium carbonate and/or ammonium hydrogencarbonate obtained in the step 3 is added to the mixed solution A2, it may be mixed. The solution A2 is sent to the compounding reaction tank through the filter. At this time, since the preparation of ammonium carbonate and/or ammonium hydrogencarbonate in the compounding reaction tank has been completed, it is also possible to directly use the carbon dioxide inlet and/or waste of the compounding reaction tank. The liquid gas inlet is used as the liquid inlet of the A2.

The discharge port is an outlet when the ammonium carbonate and/or ammonium hydrogencarbonate needs to be transported to the sub-liquid mixing tank in the reaction reaction tank (at this time, whether the mixed solution A2 passes through the chemical reaction tank or not, whether it is mixed or not is considered. The solution A2 does not pass through the compounding reaction tank, or it may be that the mixed solution A2 is flushed to dissolve the ammonium carbonate and/or the ammonium hydrogencarbonate is insufficient, and the discharge port is required to deliver ammonium carbonate and/or ammonium hydrogencarbonate. Since the preparation of ammonium carbonate and/or ammonium hydrogencarbonate is completed when ammonium carbonate and/or ammonium hydrogencarbonate are sent out of the chemical reaction tank, it is also possible to directly use the carbon dioxide inlet and/or the waste gas inlet of the chemical reaction tank as described above. Use at the discharge port.

More preferably, a heating device is provided in the vicinity of the carbon dioxide inlet and/or the waste gas inlet and/or the liquid inlet of the compounding reaction tank, so that the above position can be maintained at a relatively high temperature, thereby effectively suppressing the solid ammonium carbonate and the position. / or the rate of production of ammonium bicarbonate to avoid clogging the above inlet.

Preferably, the compounding reaction tank is connected to the fluidic device;

The jet vacuum device has a gas-liquid mixing chamber and a collecting cylinder, wherein the collecting cylinder has water for dissolving the reaction reaction tank exhaust gas; the gas-liquid mixing chamber is respectively provided with a jet suction port, a jet inflow port and The injection liquid outlet is inserted into the collection cylinder through the liquid discharge pipe; the injection liquid inlet is connected to the collection cylinder through the absorption liquid circulation pipe and the liquid inlet pump disposed on the pipe. The fluidic device can be used to absorb the aqueous solution of the tail gas of the ammonium carbonate and/or ammonium bicarbonate synthesis reaction for the formulation of the recycled regeneration etchant liquid in the sub-liquid mixing tank.

Preferably, the collection tank of the fluidic device is provided with a pH meter for detecting the pH of the liquid in the collection cylinder.

The beneficial effects of the invention are:

1) In the process of treating alkaline copper ammonium chloride etching waste liquid, the invention does not introduce new acid ions and the like, and does not contain an organic extractant, thereby realizing the recycling of the alkaline copper chloride ammonium etching waste liquid. The etching waste liquid is recovered and regenerated into an etching liquid, and is recycled in the etching process. Moreover, the regenerated etching liquid can maintain the normal etching rate and quality index after being reused, which can greatly reduce the cost of etching production. Moreover, it is also green and environmentally friendly, so that waste recycling in the true sense.

2) The recycled etchant liquid recovered by the present invention does not contain an organic extractant, and not only maintains the normal etching rate and quality index, but also avoids ammonia nitrogen pollution.

3) According to the invention, since the NH ⁴⁺ in the alkaline copper chloride ammonium etching waste liquid is recovered, the quality requirement can be satisfied without adding or adding only a small amount of ammonia water in the preparation of the recycled etching liquid solution, so the etching liquid liquid is The volume change is extremely small, and a large amount of surplus is not generated during use, and the amount of etchant liquid overflowing in the etching bath is reduced to avoid unnecessary energy consumption.

4) The invention can recover NH ⁴⁺ in the alkaline copper chloride ammonium etching waste liquid, and solves the problem that the traditional alkaline alkaline copper chloride ammonium etching waste liquid discharges ammonia nitrogen pollutants into the environment.

DRAWINGS

1 is a flow chart of a process for recycling an etching waste liquid according to Embodiments 1, 11, and 16 of the present invention;

2 is a flow chart of a process for recycling an etching waste liquid according to Embodiment 2 of the present invention;

3 is a flow chart of a process for recycling an etching waste liquid according to Embodiments 3, 8, 9, 12, 13, and 20 of the present invention;

4 is a flow chart of a process for recycling an etching waste liquid according to Embodiment 4 of the present invention;

5 is a flow chart of a process for recycling an etching waste liquid according to Embodiments 5, 7, 10, 14, 15, and 17 to 19 of the present invention;

6 is a flow chart of a process for recycling an etching waste liquid according to Embodiment 6 of the present invention;

Fig. 7 is a flow chart showing the process of recycling the etching waste liquid according to the twenty-first embodiment of the present invention.

In the figure, 1 is an acid-base adjusting tank; 2 is a heating evaporation tank; 3 is a compounding reaction tank; 4 is a sub-liquid mixing tank; 5 is a filter; 6 is a jet device; J is an alkaline etching waste liquid; C is Precipitate; X is an aqueous solution; Y is other desired components; Z is a regenerative etching solution; 1-1 is a first acid-base conditioning tank; 1-2 is a second acid-base conditioning tank; A heating evaporation tank; 2-2 is a second heating evaporation tank; 3-1 is a first chemical reaction tank: 3-2 is a second chemical reaction tank.

Detailed ways

The present invention will be further described in conjunction with the accompanying drawings and embodiments.

In the following examples and comparative examples, the ammonium chloride used is ammonium chloride produced by Guangzhou Chemical Reagent Factory; the ammonia water used is ammonia water produced by Guangzhou Chemical Reagent Factory; the copper chloride used is Guangzhou chemical reagent. CuCl ₂ ·2H ₂ O (≥99.0%) produced by the factory; the ammonium carbonate used is ammonium carbonate produced by Shanghai Hengyuan Biotechnology Co., Ltd.; the ammonium bicarbonate used is produced by Shanghai Yuke Pharmaceutical Technology Development Co., Ltd. Ammonium bicarbonate; the alkaline etching solution additive used is YH-302, YH-303, YH-304 alkaline etching additive produced by Guangzhou Shigao Chemical Co., Ltd.; the automatic detection and feeding control machine used is Guangzhou City High-tech PCB alkaline etching automatic control machine type-2 (alkaline copper chloride etching system) produced by Gao Chemical Co., Ltd.; the alkaline etching waste liquid used is from Guangzhou Shigao Chemical Co., Ltd.; the acidity used Etching waste liquid S is from Guangzhou Shigao Chemical Co., Ltd.

In addition to the above enumerated, those skilled in the art can achieve the object of the present invention by selecting other products having similar properties to those of the above-listed products according to the conventional selection.

The preparation method of the alkaline etching waste liquid of Example 1 is as follows:

Step 1: Under normal temperature and normal pressure, respectively, according to the components specified in the circulating regeneration etchant liquid in Table 1, respectively, the selected raw materials are dissolved in water to prepare an etchant liquid;

Step 2: Add copper chloride to the etching solution obtained in each liter of step 1. The amount of copper chloride added is calculated according to the copper ion concentration setting in the solution listed in Table 1:

Wherein, the molar mass of copper chloride is 134.5 g/mol; the molar mass of copper ions is 63.5 g/mol; according to the value specified in Example 1 of Table 1, corresponding copper chloride should be added per liter of the etching solution. 190.6g.

Step 3: Pour the solution obtained in step 2 into an etching tank, and immerse the detection probe that automatically detects each parameter of the feeding control machine into the etching liquid;

Step 4: Pour the etching solution liquid obtained in the step 1 into the etching liquid tank connected to the gravity meter in the automatic detection and feeding control machine. The temperature of the etching cylinder was set to 50 ° C, and the etching liquid nozzle pressure of the etching machine was set to 2 kg/cm ² ;

Step 5: Start the etching operation, automatically detect the feeding control machine to automatically place the etching liquid, and supplement the components in the balancing etching liquid so that the specific gravity is maintained at the specific gravity value specified in Table 1. During the etching process, the pH of the etching liquid is automatically detected by the feeding control machine, and the detected value is recorded in Table 1;

Step 6: The etching rate and the etching factor K test were performed on the etching solution, and the results are shown in Table 1. The etching working solution after the etching test was completed as the alkaline etching waste liquid, and the steps of the following examples were continued.

Etch quality test

An etch factor test circuit board having a size of 620×540 mm, a copper thickness of 1 oz, a development line width of 50.8 μm, and a 500×300 mm×1.5 mm pure copper etch rate test board were placed in an etching machine for spray corrosion. Testing, and using methods known in the industry ("Printed Circuit Technology", Li Xueming, Ministry of Industry and Information Technology, Electronic Industry Vocational Skills Identification Guidance Center, Fifth Edition, p387-389; "Metal Corrosion Theory and Application", Wei Baoming, Chemical Industry Press, p5-7; "On the calculation method of etching factor", Tian Ling et al., Printed Circuit Information 2007 No. 12, p55-56) Calculate the etching rate and the etching factor K. The calculation results of the etching rate and the etching factor K are shown in Table 2.

The preparation method of the alkaline etching waste liquid of Example 2 is as follows:

The content of each component of the etching solution used in the preparation of the alkaline etching waste liquid of Example 2 was 20% by weight of ammonium chloride, 21% by weight of ammonia water, 10% by weight of the additive, and the balance was water. The pH control parameter of the automatic detection feeding controller was 7.2, the specific gravity was controlled to 1.31 g/ml, and the copper ion concentration parameter was as listed in Table 1 below, and the method of preparing the alkaline etching waste liquid of Example 1 was repeated.

The etching quality test was carried out in accordance with the method described in Example 1 for preparing an alkaline etching waste liquid.

The content of each component of the etching solution in the preparation process of the alkaline etching waste liquid of Examples 3-20 is consistent with the content of each component of the circulating regeneration etching liquid in Table 1, and the parameters of the automatic detection feeding machine are shown in Table 1 below. Column, the method of preparing the alkaline etching waste liquid of Example 1 was repeated.

The etching quality test was carried out in accordance with the method described in Example 1 for preparing an alkaline etching waste liquid.

Example 1

(1) Gas-liquid separation of etching waste liquid: a heating device is provided inside the heating evaporation tank 2, and the alkaline etching waste liquid J of the parameters in Table 1 is heated to boiling in the heating evaporation tank 2 to be evaporated, and concentrated for 12 hours to the naked eye. It can be seen that after the precipitate CC is precipitated, the solid-liquid mixture A1 is obtained and discharged into the acid-base adjusting tank 1; the gas escaping during the heating is collected and introduced into the compounding reaction tank 3;

(2) Adjustment of pH value: hydrochloric acid is added to the acid-base adjusting tank 1 and mixed with the solid-liquid mixture A1 in the tank to adjust the pH to 3, and filtered by the filter 5 to obtain a precipitate C and a mixed solution A2, the precipitate The main component of the substance C is solid basic copper chloride;

(3) Gas treatment: a carbon dioxide compressed gas is added to the chemical reaction tank 3, and under the concentration adjustment of the carbon dioxide compressed gas, the carbon dioxide concentration in the chemical reaction tank 3 is higher than the ammonia gas concentration to carry out a chemical reaction and maintain carbon dioxide. And a molar ratio of ammonia to about 2:1, to obtain ammonium hydrogencarbonate;

(4) Mixing of the solution: The ammonium hydrogencarbonate obtained in the step (3) is scraped from the chemical reaction tank 3, dissolved in the A3 solution to form an A3 mixed solution, and then discharged into the sub-liquid mixing tank 4, and used in the industry. Well-known method ("Determination of ammonia and carbon dioxide in ammonium carbonate for chemical raw materials", Li Rong, Metallurgical Analysis, Vol.24No.1, p78-79; "GB320-2006 Industrial Synthetic Hydrochloric Acid", China National Standardization Administration Committee, P2-3; "Lithium ion determination method and its application research", Yu Lingyun, etc., Western Leather Vol.31No.15, p32-42) and the test method in the additive manual for the determination and calculation of the components in the A3 mixed solution concentration;

(5) Regeneration of the etching liquid: In the sub-liquid mixing tank 4, according to the recycling ratio of the circulating regenerant liquid required in the etching process in Table 1, the chemical raw material which is lacking is added to the mixed solution A3 to prepare a recycling regenerator liquid. The concentration of copper ions in the A3 mixed solution need not be considered in the preparation, and only the concentration of other components is required to reach the set standard, as in the remaining examples below. The prepared recycling etchant liquid is automatically detected by the automatic detection and feeding control machine according to the specific gravity parameter in Table 1 and applied to the etching production line for etching, and the method is prepared according to the method of preparing the alkaline etching waste liquid J. Quality test. The etching rate and the etching factor K are shown in Table 1.

Embodiment 2, referring to FIG. 2

(1) Gas-liquid separation of etching waste liquid: heating means are provided inside and outside of the heating evaporation tank 2, and the parameters of the parameters in Table 1 are alkaline using a heating evaporation tank 2 provided with an external pressurized air cannula and a motorized stirring device. The etching waste liquid J is heated to boiling to evaporate, and the external pressurized air cannula is opened to drive the outside air into the heating evaporation tank 2 to stir the mixture in the tank, and the mixture is concentrated for 1 hour until the precipitate is formed by the naked eye, and the heating is stopped. The external pressurized air cannula continues to work to accelerate the cooling of the heated evaporation tank 2; the A1 solid-liquid mixture is obtained and pumped into the acid-base adjusting tank 1; the gas escaping during the heating is collected and introduced into the first compound In the reaction tank 3;

(2) pH adjustment: Pour the A1 solid-liquid mixture and the circuit board acidic etching waste liquid S into the acid-base adjusting tank 1 to adjust the pH value to 6,

(3) Gas treatment: the first compounding reaction tank 3 is connected to the second compounding reaction tank 3 provided with the jet device 6 for exhaust gas guided collection and treatment; and the first compounding reaction tank is adjusted under the adjustment of the concentration of the carbon dioxide compressed gas. The ratio of the ammonia gas concentration to the carbon dioxide concentration is about 6:1 to obtain ammonium carbonate, so that the carbon dioxide concentration of the second compound reaction tank 3 is higher than the ammonia gas concentration and maintains the molar concentration of carbon dioxide and ammonia gas. The ratio is about 1.5:1 to obtain ammonium bicarbonate by reaction; the tail gas of the second compounding reaction tank 3 is absorbed by mixing with the connected jet device 6 and water;

(4) Mixing of the solution: the solid mixture (containing basic copper chloride) is filtered through a filter 5 while flushing the first and second chemical reaction tanks 3 using the filtrate A2 by filtration pressure so that the obtained in the step (1) is obtained. Ammonium carbonate and ammonium bicarbonate are taken out from the tank to form an A3 mixed solution; then discharged into the sub-liquid mixing tank 4;

(5) Regeneration of the etching sub-liquid: in the sub-liquid mixing tank 4, according to the circulation regenerating liquid liquid distribution ratio required in the etching process in Table 1, the mixing solution obtained in the refilling step (1) is added to the A3 mixed solution. The aqueous regenerative etching solution Z is prepared after the aqueous solution X and other desired components. The prepared circulating regeneration etching liquid is automatically detected by the automatic detection and feeding control machine according to the specific gravity parameter and the pH parameter in Table 1 and applied to the etching production line for the etching process, and the alkaline etching waste liquid J is prepared according to the alkaline etching waste liquid J. The method was etch quality tested and the etch rate and etch factor K are reported in Table 1.

Embodiment 3, referring to FIG. 3

(1) Gas-liquid separation of etching waste liquid: a heating device is provided outside the heating evaporation tank 2, and the alkaline etching waste liquid J of the parameters in Table 1 is heated to boiling in the heating evaporation tank 2, and concentrated by evaporation for 5 hours to the naked eye. It can be seen that after the precipitate C is precipitated, the solid solution mixture of A1 is obtained and discharged into the acid-base adjusting tank 1; the gas escaping during the heating is collected and introduced into the compounding reaction tank 3;

(2) Adjustment of pH: The A1 solid-liquid mixture and hydrochloric acid were poured into the acid-base adjusting tank 1 to adjust the pH to 4, and filtered through a filter 5 to obtain a solid mixture (containing basic copper chloride).

(3) treatment of the gas: under the adjustment of the concentration of the carbon dioxide compressed gas, the first reaction tank 3 has a low ammonia gas concentration and a carbon dioxide concentration of about 5:1 to obtain ammonium carbonate;

(4) Mixing of the solution: simultaneously using the filtrate A2 to flush the chemical reaction tank 3 by using the filtration pressure, the ammonium carbonate obtained in the step (1) is taken out from the tank to form an A3 mixed solution; and then discharged to the sub-liquid mixing tank 4 Inside;

(5) Regeneration of the etching liquid: In the sub-liquid mixing tank 4, according to the recycling ratio of the circulating regenerant liquid required in the etching process in Table 1, the reconstituted etchant is prepared by adding the required components to the A3 mixed solution. Liquid Z. The prepared recycling etchant liquid is automatically detected by the automatic detection and feeding control machine according to the pH parameter in Table 1 and applied to the etching line for the etching process, and is etched according to the method described in the alkaline etching waste liquid J preparation. The quality was tested and the etch rate and etch factor K are reported in Table 1.

Embodiment 4, referring to FIG. 4

(1) Gas-liquid separation of etching waste liquid: The alkaline etching waste liquid J of the parameter in Table 1 was heated to 100 ° C using a heated evaporation tank 2 provided with a reflux stirring device and externally provided with a heating device, and concentrated by evaporation for 8 hours. After the precipitation of precipitate C is visible to the naked eye, the solid-liquid mixture of A1 is obtained and discharged into the acid-base adjusting tank 1; the gas escaping during the heating is collected and introduced into the first and second chemical reaction tanks 3, respectively. in;

(2) Adjustment of pH value: Pour the A1 solid-liquid mixture and the circuit board acidic etching waste liquid S into the acid-base adjusting tank 1 to adjust the pH value to 5, and filter through the filter 5 to obtain a solid mixture (containing a basic type) Copper chloride)

(3) Gas treatment: under the adjustment of the concentration of the carbon dioxide compressed gas, the ammonia gas concentration of the first compound reaction tank 3 is made to be low by about 7.5:1 to obtain ammonium carbonate, and the second compound reaction is obtained. The carbon dioxide concentration of the tank 3 is higher than the ammonia gas concentration concentration and the molar ratio of carbon dioxide to ammonia gas is kept at a concentration ratio of about 10:1 to obtain ammonium hydrogencarbonate;

(4) Mixing of the solution: The first and second chemical reaction tanks 3 are washed by the filtrate A2 by the filtration pressure in the filter 5, and the ammonium carbonate and ammonium hydrogencarbonate obtained in the step (1) are taken out from the tank to become A3 mixed solution; then discharged into the sub-liquid mixing tank 4;

(5) Regeneration of the etching liquid: In the sub-liquid mixing tank 4, according to the recycling ratio of the circulating regenerant liquid required in the etching process in Table 1, the reconstituted etchant is prepared by adding the required components to the A3 mixed solution. Liquid Z. The prepared circulating regeneration etching liquid is automatically detected by the automatic detection and feeding control machine according to the specific gravity parameter in Table 1 and applied to the etching production line for the etching process, and is etched according to the method described in the alkaline etching waste liquid J preparation. The quality was tested and the etch rate and etch factor K are reported in Table 1.

Embodiment 5, referring to FIG. 5

(1) Gas-liquid separation of etching waste liquid: The alkaline etching waste liquid J of the parameter in Table 1 was heated to 50 ° C using a heating evaporation tank 2 provided with a motor stirring device and externally provided with a heating device, and concentrated by evaporation for 48 hours. After the precipitate C is precipitated, the solid-liquid mixture of A1 is obtained and discharged into an acid-base adjusting tank 1. The gas escaping during the heating is collected and introduced separately to the jet device 6 for exhaust gas guided collection. Treated in the first and second compound reaction tanks 3;

(2) Adjusting the pH value: mixing the A1 solid-liquid mixture with the circuit board acidic etching waste liquid S in the acid-base adjusting tank 1 to adjust the pH value to 5, and filtering through the filter 5 to obtain a solid mixture (containing basic chlorination therein) copper);

(3) Gas treatment: under the adjustment of the concentration of the carbon dioxide compressed gas, the ammonia gas concentration of the first compound reaction tank 3 is reduced to a concentration of about 5.2:1 to obtain ammonium carbonate, and the second compound reaction is obtained. The carbon dioxide concentration of the tank 3 is higher than the ammonia gas concentration concentration and the molar ratio of carbon dioxide to ammonia gas is maintained at about 1.01:1 to obtain ammonium hydrogencarbonate; the tail gas of the compounding reaction tank 3 passes through the connected fluidic device 6 and water. Mixing and absorbing; the collecting cylinder of the jet device 6 is provided with a pH meter for pH detection of the solution in the collecting cylinder, and automatically controls the amount of carbon dioxide entering the second compounding reaction tank 3 by the measured value;

(4)) Mixing of the solution: The filter 5 washes the first and second chemical reaction tanks 3 using the filtrate A2 by the filtration pressure, and the ammonium carbonate and ammonium hydrogencarbonate obtained in the step (1) are taken out from the tank to become A3. Mixing the solution; then draining into the sub-liquid mixing tank 4;

(5) Regeneration of the etching liquid: In the sub-liquid mixing tank 4, according to the recycling ratio of the circulating regenerant liquid required in the etching process in Table 1, the A3 mixed solution is added and added to other required components to prepare a recycling re-etching. Sub-liquid Z. The prepared circulating regeneration etching liquid is automatically detected by the automatic detection and feeding control machine according to the specific gravity parameter in Table 1 and applied to the etching production line for the etching process, and is etched according to the method described in the alkaline etching waste liquid J preparation. The quality was tested and the etch rate and etch factor K are reported in Table 1.

Embodiment 6, referring to FIG. 6

(1) Gas-liquid separation of etching waste liquid:

The heating evaporation tank 2 is provided with a heating device outside, and the alkaline etching waste liquid J of the parameters in Table 1 is heated to boiling, and concentrated by evaporation for 8 hours until the precipitate C is precipitated by the naked eye, and the A1 solid-liquid mixture is obtained and pumped. Discharge into the acid-base adjusting tank 1; the gas escaping during the heating process is collected and introduced into the compounding reaction tank 3, so that the ammonia gas concentration of the compounding reaction tank 3 is lower than the carbon dioxide concentration by about 5.2:1 to obtain a reaction. Ammonium carbonate

(2) Adjustment of pH: The A1 solid-liquid mixture is mixed with hydrochloric acid in the acid-base adjusting tank 1 to adjust the pH to 4, and the solid mixture (containing basic copper chloride) is filtered by the filter 5, and filtered. Using the filtrate A2 to flush the chemical reaction tank 3, the ammonium carbonate obtained in the step (1) is taken out from the tank to form an A3 mixed solution; and then discharged into the sub-liquid mixing tank 4;

(3) treatment of the gas: making the ammonia gas concentration of the compounding reaction tank 3 and the carbon dioxide concentration low ratio of about 5.2:1 to obtain ammonium carbonate by reaction;

(4) Mixing of the solution: the filter 5 uses the filtrate A2 to flush the compounding reaction tank 3 by the filtration pressure, and the ammonium carbonate obtained in the step (1) is taken out from the tank to form an A3 mixed solution; and then discharged to the liquid mixture. Inside the slot 4;

(5) Regeneration of the etching liquid: In the sub-liquid mixing tank 4, according to the recycling ratio of the circulating regenerant liquid required in the etching process in Table 1, the reconstituted etchant is prepared by adding the required components to the A3 mixed solution. Liquid Z, and automatically detected by the automatic detection and feeding control machine according to the specific gravity parameter in Table 1, adding and recycling etchant liquid Z, and automatically detecting and adding 25% ammonia solution X according to the pH value on the etching line for the etching process, The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Example 7

The contents of the respective components of Example 7 and the parameters of the automatic detection dosing control machine are as listed in Table 1 below, and the method of Example 5 was repeated. Here, the ratio of the ammonia gas concentration of the first compounding reaction tank 3 to the carbon dioxide amount concentration is about 9:1 to obtain ammonium carbonate by reaction.

The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Example 8

The contents of the respective components of Example 8 and the parameters of the automatic detection charge control machine are as listed in Table 1 below, and the method of Example 3 was repeated. Among them, the alkaline etching waste liquid J of the parameters in Table 1 was heated to boiling and concentrated by evaporation for 6 hours.

The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Example 9

The contents of the respective components of Example 9 and the parameters of the automatic detection of the charge control machine are as listed in Table 1 below, and the method of Example 3 was repeated. Among them, the alkaline etching waste liquid J of the parameters in Table 1 was heated to boiling and concentrated by evaporation for 12 hours.

The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Example 10

The contents of the respective components of Example 10 and the parameters of the automatic detection charge control machine are as listed in Table 1 below, and the method of Example 5 was repeated. Among them, the alkaline etching waste liquid J of the parameters in Table 1 was heated to boiling and concentrated by evaporation for 15 hours.

The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Example 11

The contents of the respective components of Example 11 and the parameters of the automatic detection charge control machine are shown in Table 1 below, and the method of Example 1 was repeated. Among them, the alkaline etching waste liquid J of the parameters in Table 1 is heated to 70 degrees Celsius and concentrated by evaporation for 3 hours, so that the carbon dioxide concentration of the compounding reaction tank 3 is higher than the ammonia gas concentration to carry out a chemical reaction and maintain carbon dioxide and ammonia gas. The molar concentration ratio is about 500:1.

The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Example 12

The contents of the respective components of Example 12 and the parameters of the automatic detection charge control machine are as listed in Table 1 below, and the method of Example 3 was repeated. Among them, the alkaline etching waste liquid J of the parameters in Table 1 was heated to boiling and concentrated by evaporation for 15 hours, and the solid-liquid mixture was manually transferred by heating the evaporation tank 2 and the acid-base adjusting tank 1 without a pipe connection, and the compound reaction was carried out. A heat generating device is provided near the liquid inlet of the tank 3.

The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Example 13

The contents of the respective components of Example 13 and the parameters of the automatic detection dosing control machine are as listed in Table 1 below, and the method of Example 3 was repeated. Among them, the alkaline etching waste liquid J of the parameters in Table 1 was heated to boiling and concentrated by evaporation for 15 hours, and a heating device was provided in the vicinity of the carbon dioxide inlet, the waste gas inlet, and the liquid inlet of the compounding reaction tank 3.

The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Example 14

The contents of the respective components of Example 14 and the parameters of the automatic detection of the charge control machine are as listed in Table 1 below, and the method of Example 5 was repeated. Among them, the alkaline etching waste liquid J of the parameters in Table 1 was heated to boiling and concentrated by evaporation for 15 hours.

The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Example 15

The contents of the respective components of Example 15 and the parameters of the automatic detection charge control machine are shown in Table 1 below, and the method of Example 5 was repeated. Wherein, the alkaline etching waste liquid J of the parameters in Table 1 is heated to boiling and concentrated by evaporation for 50 hours, so that the ammonia gas concentration of the first compounding reaction tank 3 is lower than the carbon dioxide concentration by about 8.3:1 to obtain carbonic acid by reaction. Ammonium.

The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Example 16

The contents of the respective components of Example 16 and the parameters of the automatic detection charge control machine are as listed in Table 1 below, and the method of Example 1 was repeated. Wherein, the alkaline etching waste liquid J of the parameters in Table 1 is heated to boiling and concentrated by evaporation for 4.5 hours, and an outlet port is provided on the compounding reaction tank 3 in addition to the carbon dioxide inlet and the waste gas inlet, so that the reaction tank 3 is compounded. The carbon dioxide concentration is higher than the ammonia concentration and the molar ratio of carbon dioxide to ammonia is about 100:1 to obtain ammonium bicarbonate, and the chemical reaction tank 3 and the sub-liquid mixing tank 4 are not connected by a pipe. The ammonium hydrogencarbonate formed in the reaction tank 3 is manually transferred.

The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Examples 17, 18

The contents of the respective components of Examples 17, 18 and the parameters of the automatic detection dosing control machine are listed in Table 1 below, and the method of Example 5 was repeated. Wherein, the alkaline etching waste liquid J of the parameters in Table 1 is heated to boiling and concentrated by evaporation for 50 hours, so that the ammonia gas concentration of the first compounding reaction tank 3 is lower than the carbon dioxide concentration by about 8.3:1 to obtain carbonic acid by reaction. Ammonium.

The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Example 19

The contents of the respective components of Example 19 and the parameters of the automatic detection charge control machine are as listed in Table 1 below, and the method of Example 5 was repeated.

The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Example 20

The contents of the respective components of Example 20 and the parameters of the automatic detection charge control machine are as listed in Table 1 below, and the method of Example 3 was repeated. Among them, the alkaline etching waste liquid J of the parameters in Table 1 was heated to boiling and concentrated by evaporation for 6 hours.

The etching quality test was carried out in accordance with the method described in the preparation of the alkaline etching waste liquid J, and the etching rate and the etching factor K are shown in Table 1.

Example 21, see Figure 7

(1) Gas-liquid separation of etching waste liquid: heating means are provided outside the first heating evaporation tank 2-1 and the second heating evaporation tank 2-2, and the alkaline etching waste liquid J of the parameters in Table 1 is first The inside of the heating evaporation tank 2-1 is heated to boiling, and the second heating evaporation tank 2-2 is heated to 30 degrees Celsius, and concentrated by evaporation for 8 hours until the precipitate C is precipitated by the naked eye, and the A1 solid-liquid mixture is obtained and separately pumped. It is discharged into the first and second acid-base adjusting tanks 1; the gas escaping during the heating process is collected and introduced into the compounding reaction, so that the ammonia gas concentration of the compounding reaction tank 3 is lower than the carbon dioxide concentration by about 5.2:1. Obtaining ammonium carbonate by reaction;

(2) Adjustment of pH value: hydrochloric acid is added to the acid-base adjusting tank 1 and mixed with the solid-liquid mixture A1 in the tank to adjust the pH to 4, and filtered by the filter 5 to obtain a precipitate C and a mixed solution A2, the precipitate The main component of the substance C is solid basic copper chloride; at the same time, the ammonium carbonate obtained in the step (1) is taken out from the tank by the filtration reaction using the filtrate A2 to form the A3 mixed solution; Into the sub-liquid mixing tank 4;

(3) Regeneration of the solution: in the sub-liquid mixing tank 4, according to the circulation regenerating liquid solution distribution ratio required by the etching process in Table 1, the reconstituted etchant liquid Z is prepared by adding the required components to the A3 mixed solution. And the automatic detection and feeding control machine automatically detects and adds the circulating regenerative etching liquid Z according to the specific gravity parameter in Table 1, and automatically detects and adds a 25% ammonia aqueous solution X according to the pH value in the etching process for the etching process, according to the alkali The etching etching solution J was prepared by the method described in the etching quality test, and the etching rate and the etching factor K are shown in Table 1.

Table 1

According to the data in Table 1, the etch rate of the recycled etchant liquid obtained by the present invention satisfies the efficiency of the current large-scale production in the industry, and there is no disadvantage of quality reduction.

The above embodiments of the present invention are not intended to limit the scope of the present invention, and the embodiments of the present invention are not limited thereto, and the above-described contents according to the present invention are based on the ordinary technical knowledge and conventional means in the art, without departing from the present invention. Other various modifications, substitutions and alterations of the above-described structures of the present invention are intended to be included within the scope of the present invention.

Claims (17)

1. A steam ammonia recovery cycle process for alkaline etching waste liquid of a circuit board, characterized in that the method comprises the following steps:

   (1) Gas-liquid separation of etching waste liquid: heating an alkaline etching waste liquid having a copper ion concentration of 30-180 g/L and a pH value of 7-9, collecting gas generated during heating to obtain a waste liquid gas; When the etching waste liquid is heated until a precipitate is precipitated, a solid-liquid mixture A1 is obtained;

   (2) Adjustment of pH value: mixing the solid-liquid mixture A1 obtained in the step (1) with hydrochloric acid and/or acid etching waste liquid and adjusting the pH to 3-6 to further increase the precipitate in the solid-liquid mixture A1, The precipitate in the obtained solid-liquid mixture A1 is separated; after solid-liquid separation, a solid precipitate and a mixed solution A2 are respectively obtained;

   (3) Gas treatment: mixing the waste liquid gas collected in step (1) with carbon dioxide to form ammonium carbonate and/or ammonium hydrogencarbonate;

   (4) mixing of the solution: adding ammonium carbonate and / or ammonium bicarbonate to the mixed solution A2 obtained in step (2), to obtain a mixed solution A3;

   (5) Regeneration of the etching solution: The other desired components of the etching process are supplemented in the mixed solution A3 obtained in the step (4), and the etching liquid is recycled.
2. The process for recycling a vaporized ammonia of a circuit board alkaline etching waste liquid according to claim 1, wherein in the step (4), the solid-liquid mixture A1 obtained in the step (1) is used in the step (2). When the pH value is adjusted and the filtration is separated, the mixed solution A2 filtered is washed with ammonium carbonate and/or ammonium hydrogencarbonate obtained in the step (3) to obtain a mixed solution A3.
3. The process for recycling a vaporized ammonia of a circuit board alkaline etching waste liquid according to claim 1, wherein in the step (3), the gas collected in the step (1) is divided into two parts to make the first part The concentration of the substance of the ammonia gas is greater than the concentration of the carbon dioxide material; the concentration of the substance of the second portion of the ammonia gas is less than the concentration of the carbon dioxide material in order to control the ratio of the produced ammonium carbonate and ammonium hydrogencarbonate.
4. A process for recycling a vaporized ammonia of a circuit board alkaline etching waste liquid according to claim 1 or claim 3, wherein said step (3) uses a jet device and uses water as a jet liquid to waste gas The tail gas of the synthesis reaction of reacting with carbon dioxide to form ammonium carbonate and/or ammonium hydrogencarbonate is absorbed.
5. The process for recovering ammonia in a circuit board alkaline etching waste liquid according to claim 4, wherein the step (3) uses a jet device and uses water as a jet liquid to react the waste gas with carbon dioxide. The tail gas of the synthesis reaction of ammonium carbonate and/or ammonium hydrogencarbonate is absorbed to obtain an aqueous solution; the pH of the aqueous solution obtained by the fluidic device is detected by a pH meter, and the amount of carbon dioxide gas in the step (3) is controlled. .
6. The process for recycling a vaporized ammonia of a circuit board alkaline etching waste liquid according to claim 1, wherein in the step (1), a stirring device is used to stir the alkaline etching waste liquid to promote the gas The stirring position escapes.
7. The process of recirculating ammonia in the alkaline etching waste liquid of the circuit board according to claim 4, wherein in the step (1), the alkaline etching waste liquid is stirred by using a stirring device to promote the gas The stirring position escapes.
8. A process for recycling a vaporized ammonia of a circuit board alkaline etching waste liquid according to claim 1 or claim 5, wherein the step (1) is performed by using external pressurized air during and/or after the heating process. The tube is blown into the alkaline etching waste liquid, and the mixture in the heating container is stirred, and the gas volatilized by the mixture is promptly introduced into the step (3) for the synthesis reaction.
9. The process for recycling a vaporized ammonia of a circuit board alkaline etching waste liquid according to claim 1, wherein the other components required for the etching process according to the step (5) include ammonium chloride, ammonia water, and ammonium hydrogencarbonate. At least one of ammonium hydrogencarbonate, water, and an etching additive.
10. A system for using a vaporized ammonia recovery cycle of a circuit board alkaline etching waste liquid according to any one of the preceding claims 1 to 9, characterized in that it comprises the following components:

    At least one acid-base adjusting tank (1) for adjusting the pH value of the remaining liquid after evaporation of the alkaline etching waste liquid;

    At least one heating evaporation tank (2), which is provided with a heating device and an air outlet disposed inside and/or outside the heating evaporation tank; for concentrating and heating the alkaline etching waste liquid and separating the waste liquid gas;

    At least one compounding reaction tank (3) provided with a carbon dioxide inlet and a waste gas inlet; the carbon dioxide inlet is connected to a carbon dioxide source, and the waste gas inlet is connected to an outlet of the heated evaporation tank for producing ammonium carbonate and / or ammonium bicarbonate;

    At least one filter for separating solids and liquids in the solid-liquid mixture, the inlet of the filter being connected to the acid-base adjusting tank, and the liquid outlet of the filter is connected to the sub-liquid mixing tank or the compounding reaction tank;

    A sub-liquid mixing tank for preparing a recirculating etchant liquid.
11. The evaporated ammonia recovery cycle system for a circuit board alkaline etching waste liquid according to claim 10, wherein the heating evaporation tank is provided with a stirring device.
12. The evaporated ammonia recovery cycle system for alkaline etching waste liquid of a circuit board according to claim 10 or 11, wherein the heating evaporation tank is provided with an external pressurized air cannula; and the external pressurized air cannula is It is composed of pipes and pumps that communicate with the outside of the heating evaporation tank.
13. The evaporated ammonia recovery cycle system for a circuit board alkaline etching waste liquid according to claim 10, wherein a pump is connected to the heating evaporation tank connected to the chemical reaction tank, and/or a pump is provided at the gas outlet of the compound reaction tank. Pu.
14. A vaporized ammonia recovery cycle system for a circuit board alkaline etching waste liquid according to claim 10, wherein said compound reaction tank is provided with an additional gas outlet, and/or an additional liquid inlet/and/or outlet Feed port.
15. The evaporated ammonia recovery cycle system for a circuit board alkaline etching waste liquid according to claim 10, wherein a heating means is provided in the vicinity of the carbon dioxide inlet and/or the waste liquid gas inlet and/or the liquid inlet of the compounding reaction tank.
16. The evaporated ammonia recovery cycle system for a circuit board alkaline etching waste liquid according to claim 10, wherein the compounding reaction tank is connected to the fluidic device;

    The jet vacuum device has a gas-liquid mixing chamber and a collecting cylinder, and the collecting cylinder has water for the dissolved reaction tank tail gas;

    The gas-liquid mixing chamber is respectively provided with a jet suction port, an injection inflow port and an injection outflow port, and the injection outflow port protrudes into the collection cylinder through the discharge pipe; the injection inflow port is circulated through the absorption liquid The tube and the influent pump disposed on the tube are connected to the collection cylinder.
17. The evaporated ammonia recovery cycle system for a circuit board alkaline etching waste liquid according to claim 14, wherein a pH meter is provided in the collection cylinder of the fluid flow device for detecting a pH value of the liquid in the collection cylinder.

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