Method for treating etching waste solvent from circuit board and / or substrate manufacturing, and circuit board and / or substrate manufacturing industrial plant

Abstract

A method for treating etching waste solvent from circuit board and / or substrate manufacturing is described, the method comprising the steps of: i) providing a to-be-treated solvent (11), in particular from an etching process (150), the to-be-treated solvent (11) having to-be-treated metal salts and acids (15); ii) treating the to-be-treated solvent (11) in an ion exchange process (145), such that the to-be-treated metal salts are exchanged with metal salts and a metal salt-containing solvent (10) is produced from the to-be-treated solvent (11). the step of obtaining a purified water (188) and / or a metal-depleted salt concentrate (186b) from said ion exchange process (145); whereby a) flowing a first process cycle (170) through said ion exchange process (145), wherein said first process cycle (170) is a first closed loop that produces substantially only elemental metal (50); and b) flowing a second process cycle (180) through said ion exchange process (145), wherein said second process cycle (180) is a second closed loop that produces substantially only purified water (188) and / or a metal-depleted salt concentrate (186b).

Description

Technical Field

[0001] The present invention relates to a method for treating etching waste solvents from circuit board and / or substrate manufacturing. Further, the present invention relates to a circuit board and / or substrate manufacturing industrial plant configured to perform the method. Further, the present invention relates to a particular use of an ion exchange process.

[0002] Accordingly, the present invention may relate to the technical field of circuit board and / or substrate manufacturing. In particular, the present invention may relate to the technical field of treating (especially recovering metals) metal salt-containing solvents from circuit board and / or substrate manufacturing. Further, the present invention may relate to the technical field of recycling (especially providing waste water that meets the drainage water quality) in circuit board and / or substrate manufacturing.

Background Art

[0003] For the production of circuit boards and / or substrates, in principle, large amounts of metals, especially heavy metals (e.g., copper, nickel, gold, silver, palladium, tin, iron) are required. Accordingly, in the manufacturing process, metal-containing residues and metal-containing solvents (especially solutions) are generated in various processes, respectively.

[0004] Metal (salt)-containing solvents (and respectively, waste to be treated and residue concentrates) substantially result from two different treatment processes in circuit board and / or substrate manufacturing: i) an etching process (e.g., etching of copper foil) and ii) a plating process (e.g., plating treatment using a copper layer). In addition, metal (salt)-containing solvents to be treated are generated during the cleaning processes from the etching process and the plating process. These cleaning waters contain only low concentrations of metals, especially copper. In contrast, the metal (salt)-containing solvents to be treated from the etching process and the plating process contain relatively high concentrations of metals.

[0005] The metal (salt)-containing solvent to be treated from the etching process usually contains metal salts in which the metal is chemically bonded to an acid salt (from the etching process), such as copper chloride, and the chloride is derived from hydrochloric acid. Further, the metal (salt)-containing solvent to be treated from the plating process usually contains metal salts in which the metal is chemically bonded to an acid salt of electrolysis, such as copper sulfate, and the sulfate is derived from sulfuric acid. In addition, the metal (salt)-containing solvent to be prepared from the plating process generally contains a high concentration of foreign metals, such as iron.

[0006] The method of recovering metal from the described metal (salt)-containing solvent is known in principle. However, only the recovered metal in a very pure form (e.g., from 99% to a maximum of 99.99%, especially about 99.9% purity) is the subject of circuit board and / or substrate manufacturing. Such recovery can be accomplished, for example, by electrolysis. However, the metal (salt)-containing solvents described above are very unsuitable for this purpose. This is because the deposition of pure metal (e.g., copper) is inhibited or complicated. High concentrations of acid, hydrogen peroxide (and foreign metals) invalidate high-quality electrolysis.

[0007] For this reason, waste concentrates from circuit board and / or substrate manufacturing have conventionally been disposed of in a cost-intensive, environmentally unfriendly, and non-durable manner, respectively. SUMMARY OF THE INVENTION

[0008] It is an object of the present invention to enable a cost-efficient, environmentally friendly, and durable treatment of waste solvents from circuit board and / or substrate manufacturing, especially from the etching process.

[0009] This object is solved by the subject matter according to the independent patent claims. Preferred embodiments result from the dependent patent claims.

[0010] According to one aspect of the present invention, a method for treating an etching (process) waste solvent from circuit board and / or substrate manufacturing is described. The method comprises: i) providing the etching waste solvent as the solvent to be treated (especially from an etching process), wherein the solvent to be treated has a metal salt to be treated and an acid; ii) treating the solvent to be treated in an ion exchange process, as a result of which the metal salt to be treated is exchanged with a metal salt and a metal salt-containing solvent is obtained from the solvent to be treated; iii) flowing a first process cycle through the ion exchange process, wherein the first process cycle is a first (closed) loop that produces (substantially) only metal elements (e.g., using an electrolysis process); and

[0011] In particular, the method further comprises iv) flowing a second process cycle through the ion exchange process, wherein the second process cycle is a second (closed) loop that produces (substantially) only purified water and / or a metal-deficient salt concentrate (e.g., using a reverse osmosis process); and may include.

[0012] According to a further aspect of the present invention, i) an etching process module that generates an etching waste solvent as the solvent to be treated, wherein the solvent to be treated has a metal salt to be treated and an acid; ii) an ion exchange process module configured to treat the solvent to be treated, as a result of which the metal salt to be treated is exchanged with a metal salt and a metal salt-containing solvent is obtained from the solvent to be treated; iii) a first process cycle flowing through the ion exchange process module (implemented as a fluid transport system via an electrolysis module, for example), wherein the first process cycle is a first closed loop that produces substantially only the metal element; and iv) a second process cycle flowing through the ion exchange process (implemented as a fluid transport system via a reverse osmosis module, for example), wherein the second process cycle is a second closed loop that produces substantially only purified water and / or a metal-deficient salt concentrate A circuit board and / or a substrate manufacturing industrial plant is described.

[0013] According to a further aspect of the present invention, an ion exchange process coupled to an electrolysis process within a first closed-loop process cycle and to a membrane filtration process within a second closed-loop process cycle is used to treat circuit board and / or substrate manufacturing etching wastewater such that (substantially) only copper elements, purified water, and / or heavy metal-deficient salt concentrates are produced.

[0014] According to a further aspect of the present invention, a process control device for adjusting the method and / or the device described above is discussed. The process control device comprises: i) a database for capturing at least one process parameter (and its respective actual value) from the process being executed, in particular a plurality of process parameters, ii) a data model unit adapted to store at least one predefined process parameter (and its respective target value), in particular a plurality of predefined process parameters, and iii) a) comparing the captured process parameters with the predefined process parameters (and the respective plurality of parameters with each other), b) determining a control action based on the result of the comparison (e.g., actively compensating for the difference between the actual value and the target value), and c) performing a predefined control action (e.g., adapting the flow rate, etc.) an arithmetic unit adapted as such is provided.

[0015] According to a further aspect of the invention, a computer program product for controlling a method for treating etching waste solvents from circuit board and / or substrate manufacturing is described, which computer program product, when executed by one or more processors (and each one or more computers), controls the method and / or the apparatus and / or the process control apparatus (as described above).

[0016] In the context of this specification, the term "metal salt-containing solvent" may in particular denote any (liquid) solvent containing a metal salt. A metal salt is a chemical compound between a metal and an acid. Examples of such metals may include: copper, nickel, gold, silver, cobalt, cadmium, magnesium, sodium, palladium, tin. Examples of acids may include: sulfuric acid, hydrochloric acid, nitrous acid, phosphoric acid; while the metal salt may correspondingly exist as, for example, sulfate, chloride, nitrate or phosphate. Correspondingly, the metal salt may be, for example, copper sulfate or copper chloride. These may exist in the metal salt-containing solvent as metal ions and salt ions. The metal salt-containing solvent may, in addition to the metal salt, include, for example, an aqueous or acidic solution in which the metal salt is dissolved. For example, the solvent may include, in addition to water, also hydrochloric acid and / or sulfuric acid. In one example, the metal salt-containing solvent results from the manufacture of a circuit board and / or substrate and may contain corresponding residues. Further, the metal salt-containing solvent may be treated so that substantially only the metal salt is present. In one example, the metal salt-containing solvent is (substantially) free of (undesirable) foreign metals (such as iron). In a further example, the metal salt-containing solvent contains foreign metal (residues). The term "solvent to be treated" may denote a solvent that is to be further treated in a subsequent treatment step. Thereby, the solvent to be treated may contain a metal salt to be treated (for example, the salt is exchanged for another salt), and when the metal salt to be treated is exchanged for a metal salt, the solvent is obtained from the solvent to be treated. In an exemplary embodiment, the metal salt to be treated contains copper chloride and the metal salt contains copper sulfate.

[0017] In the context of this specification, the term "process cycle" may in particular denote a certain amount of process steps (and / or process modules) connected in a cyclic manner. In particular, the process cycle may be arranged such that the product of one first step is fed back to a second step which is a process upstream of the first step. Even more particularly, the product of the final step is fed back as input to the first step. Such an embodiment may be referred to by the term closed-loop process cycle. Preferably, the closed-loop process cycle is carried out so as not to generate waste. This may be achieved, for example, using a third process cycle, where the strong acid from the etching process is separated within a membrane dialysis and then fed back to the etching process via a concentration step. In another embodiment, the first process cycle may produce, as waste, only metal elements (for example, by flowing an acidic solvent through an ion exchange process, transporting the immobilized metal ions to an electrolysis process that produces metal elements, and feeding back the metal-deficient acidic solvent), where the metal elements are, however, a desirable product that can be fed back to another manufacturing process. In another embodiment, the second process cycle may produce, as waste, only purified water and a salt concentrate lacking in metal (and thus prone to drainage) (for example, by flowing a further acidic solvent through an ion exchange process, through a reverse osmosis process, and back to the ion exchange process).

[0018] In the context of this specification, the term "foreign metal" may in particular denote a metal that is present (in dissolved form) in a metal salt-containing solvent but is undesirable there (for a particular application). Depending on the application, examples of such foreign metals (and their respective ions) are: iron (Fe 3+ , Fe 2+ ), lead (Pb 2+ ), tin (Sn 2+ ), molybdenum (Mo 3+ ), nickel (Ni 2+ ), cobalt (Co 2+ ), indium (In 3+ ), cadmium (Cd2+ ) Zinc (Zn 2+ ) Chromium (Cr 3+ ) Sodium (Na + ) Palladium (Pd 2+ ) may be included. In one embodiment, the metal salt-containing solvent should be processed so that the metal of the metal salt exists in elemental form and can be recycled. Heterometals can cause interference or failure of the treatment (e.g., by electrolysis), and thus it may be recommended to remove the heterometals in advance. In an exemplary embodiment, the metal salt-containing solvent results from an electroplating process, and the copper element should be obtained from the metal salt copper sulfate. Due to the electroplating process, the metal salt-containing solvent may contain heterometals, especially iron. The heterometal may exist as a heterometal salt (e.g., iron sulfate). Thereby, the electrolysis of copper sulfate can be greatly interfered with (suppressing copper deposition at the cathode). At lower (residue) concentrations, the heterometal can be oxidized during recovery, while the metal is reduced (and deposited respectively).

[0019] In the context of this specification, the term "heterometal and metal salt-containing solvent" may particularly refer to a solvent containing a metal salt-containing solvent (as described above) and a heterometal (as described above). In one embodiment, the heterometal and metal salt-containing solvent results from an electroplating treatment. In particular, the heterometal and metal salt-containing solvent is a strongly acidic solvent (e.g., having a pH value < 1). This can result from the fact that the heterometal and metal salt-containing solvent contains a strong acid such as sulfuric acid at a high concentration (e.g., in the range of 100 - 200 g / L).

[0020] In the context of this specification, the term "treatment" may particularly refer to the treatment of a solvent to be treated (especially a solvent having at least one undesirable property) during one or more process steps, resulting in the existence of a treated solvent (especially a solvent no longer having the undesirable property). For example, the solvent to be treated may be a metal salt-containing solvent with at least one metal salt being an undesirable metal salt-containing solvent. Correspondingly, the solvent to be treated can be treated (e.g., by membrane dialysis and carrying out chemical reactions) so that there exists a metal salt-containing solvent as a treated solvent that no longer (substantially) contains the undesirable metal salt.

[0021] In the context of this specification, the term "partial stream" may in particular indicate that during a (manufacturing) process, a solvent (in particular a liquid solvent) is flowed in a specific (desired) process direction. In other words, the flow of the solvent during the (manufacturing) process can be controlled in a desired manner. The term "partial stream" may in particular relate to the fact that the corresponding (manufacturing) process includes at least two such streams (from different process steps). Each single stream (of a preferred liquid solvent) within the same (manufacturing) process and within the same industrial plant can be indicated as a partial stream. A partial stream can be (specifically) a controlled flow of production waste solvent. At least two (in particular three or more) of the at least partial streams can be combined into a total stream. In one embodiment, the first partial stream includes a processed metal salt-containing solvent (e.g., containing copper sulfate and hydrochloric acid) and a waste stream respectively from an etching process for circuit board and / or substrate manufacturing, while the second partial stream includes a processed metal salt-containing solvent (e.g., containing copper sulfate, iron sulfate and sulfuric acid) and a waste stream respectively from a plating process for circuit board and / or substrate manufacturing. In one example, these can be combined with a total stream, and the total stream is then processed, for example, to recover the metal of the metal salt in elemental form.

[0022] In the context of this specification, the term "circuit board and / or substrate manufacturing" may in particular denote the processes for manufacturing circuit boards and / or substrates, which are carried out in industrial plants, for example circuit board factories. The term "circuit board" may in particular relate to printed circuit boards (PCBs), while the term "substrate" may relate to substrates for semiconductor chips such as integrated circuits or organic interposers, for example. Circuit board and / or substrate manufacturing usually encompasses an etching process in which metal is removed by etching so as to obtain a desired metal structure, and a plating process in which metal is disposed by plating. The starting materials for circuit board and / or substrate manufacturing substantially include electrical insulating materials, which are often metals and organic materials such as resins. The products of the process can be finished circuit boards and respective substrates, or intermediate products as well.

[0023] As used herein, the term "etching process" may specifically refer to a process for manufacturing a circuit board and / or a substrate, including etching a metal, particularly copper, thereby providing a desired metal (conductive) structure. According to an exemplary embodiment, this process may be performed as follows: The photoresist protects the copper paths that should not be removed by etching, while the copper regions to be removed by etching are not covered by the photoresist. First, for this purpose, the entire copper layer is coated with the photoresist. Next, through a mask, the photoresist is developed by ultraviolet light. The mask allows ultraviolet light to pass only at the positions where the photoresist should remain (i.e., the positions where the desired conductor traces should be provided). During development, the resist (and each polymer) cross-links at the positions exposed to ultraviolet light. After development, the unexposed (and each undeveloped) photoresist can be easily washed away. Thereafter, the panel (and each preform of the component carrier) is etched. The photoresist protects the conductor traces, while the copper not covered by the photoresist is etched / removed. When the etching process is completed, the photoresist is removed and each peeled off (the resist is cross-linked and solid), and the conductor traces remain. The stripped photoresist can be later precipitated by iron chloride.

[0024] In the context of this specification, the term "plating process" may in particular denote a process during the manufacture of a circuit board and / or substrate on which the plating process is carried out. The plating process may denote the electrochemical deposition of a metal precipitate on a device. The device functions as a circuit board and / or substrate on which the metal precipitate (e.g., copper) can function as a conductive layer structure and as conductor traces, respectively. Further, for example, holes (vias) can be made conductive by plating laterally or by completely filling them by plating. In one example, an electric current is applied to an electrolytic bath. The metal to be disposed (e.g., copper or nickel) is disposed on the positive electrode (anode), and the object to be coated (e.g., a circuit board) is disposed on the negative electrode (cathode). By means of the electric current, metal ions are deposited on the object by reduction. In one example, the process can be realized by means of a series of electrolytic baths. The plating process can be carried out continuously or discontinuously (in a batch-wise manner). Usually, a certain amount of the metal salt-containing solvent is obtained in the process as waste concentrate ("bleed"). Due to the process, this generally contains contents of foreign metals and strong acids, with the result that hitherto it has not been possible to recycle the metals (metal salts) in an economic manner.

[0025] In the context of this specification, the term "reaction cell" may in particular denote any reactor that enables the recovery of the metal of a metal salt from a metal salt-containing solvent in elemental form and in a very pure form. The term "recovery" may in particular denote that the metal element from the metal salt-containing solvent is separated and each isolated (for reuse purposes). An example of a reaction cell may be an electrolytic cell. The term "electrolysis" may in particular mean that an electric current is utilized to enable a chemical redox reaction. Thus, an electrolytic cell may include a direct voltage source for providing an electric current, coupled to a cathode (negative electrode) and an anode (positive electrode). The voltage source may cause a lack of electrons at the anode and an excess of electrons at the cathode. In one embodiment, a metal salt-containing solvent is added to the electrolytic cell, which contains copper as the metal and iron as the foreign metal. Copper has a higher redox potential (is more inert) and is thus reduced and respectively deposited at the cathode. In contrast, iron is oxidized at the anode. In an exemplary embodiment, the reaction cell preferably includes a plurality of (e.g., 20) electrolysis modules, among which a metal element (e.g., copper) is deposited at the cathode. In this reaction, oxidation of a foreign metal (of the electrolyte) that is less chemically inert than the deposited metal occurs. In one example, the recovery may be realized as a series of electrolytic baths. The recovery may be carried out continuously or discontinuously (batchwise).

[0026] In the context of this specification, the term "ion exchange process" may in particular denote any process suitable for the exchange of ions of a liquid solvent. The term "ion exchanger" may include a material (and respectively a device) by which dissolved ions can be replaced by other ions of the same charge (positive or negative) (see further detailed description below).

[0027] In the context of this specification, the term "dialysis" may in particular indicate the removal of molecules (especially ions) from a solution using a concentration-driven membrane process. In one embodiment, a metal salt-containing solvent is provided via a first feed (dialysate feed) on a first side of the membrane, and via a second feed (diffusate feed), a further solvent (e.g. water) is provided on a second side (opposite the first side) of the membrane. The membrane may be semi-permeable and allows anions (e.g. chloride) to pass through (anion membrane), while cations (e.g. Cu 2+ ) are not allowed to pass through. Thus, cations are concentrated in the metal salt-containing solvent as the dialysate, while anions are concentrated in the further solvent as the diffusate. In the example of chloride anions, the diffusate becomes strongly acidic, and as a result, the term "acid dialysis" may also be used.

[0028] For the membrane dialysis described below, the same membrane may be used respectively, or (preferably) different membranes are used. The anion membrane may be functionalized with, for example, bromine (Br - ), where the carrier material may be, for example, PET or PVC. In certain cases, the metal salt-containing solution may contain hydrogen peroxide (H2O2). In this case, preferably, an oxidation-resistant membrane based on, for example, PEEK (polyetheretherketone) may be used.

[0029] In the context of this specification, the term "regeneration" may in particular indicate that the (selective) ion exchanger is moved from a first operating state to a second operating state. In particular, in the first operating state, metals (in particular cations) are adsorbed by the ion exchanger (and each ion exchange resin respectively). Furthermore, in particular in the second operating state, the metals are substantially desorbed. Thus, in the second operating state, the ion exchanger may be operable to be reloaded and, correspondingly, may return to the first operating state again. Advantageously, the regeneration may be repeated multiple times. In one example, the regeneration is performed by a regeneration solvent, in particular a regeneration acid such as sulfuric acid and / or hydrochloric acid. In the regeneration, the regeneration solvent may desorb the adsorbed metals. After purification, the regeneration solvent may be used again. In a further example, there is no need to purify the regeneration solvent, so that the metal concentration in the regeneration solvent increases for each (regeneration) cycle through the ion exchanger. Thus, in this specification, "regeneration" may also be the concentration of the recovered metal.

[0030] In other words, according to one embodiment, the metal concentration increases while the acid concentration decreases. The regeneration acid already containing the desorbed metal ions is reused until the obtained acid concentration is too low to release the metal ions from the resin. Next, since the protons (H + ) of the acid remain continuously in the resin, the acid concentration decreases.

[0031] In the context of this specification, the term "useful material cycle" may in particular indicate that a plurality of useful materials (substances required for the manufacturing process, such as the main component and / or starting material / raw material) are always (and respectively, continuously) recycled within the manufacturing process (and each industrial plant). In particular, a plurality of useful materials from a single process step are processed and / or recovered and supplied again to a single process step. Useful materials are constituents of waste solvents and respectively leave the process step as generated residues, but can be fed back after an in-process process within the process. Useful materials can include, for example, heavy metals such as copper, nickel, gold, etc. These can occur in a metal salt-containing solvent in various process steps. The generated residues can be flowed in a partial stream (the flow of the solvent can be specifically controlled) and can be at least partially processed together so that useful materials can be recovered. Finally (in particular via the treatment of the entire stream), a separation stream can be separated from the partial stream that is fed back to a single process step, which can in turn be fed back to a single process step and / or supplied again to the partial stream via processes such as concentration (and respectively adjustment of the concentration).

[0032] In the context of this specification, the term "solvent meeting the wastewater quality" may in particular indicate a (liquid) solvent that is permitted to be flowed into a wastewater treatment plant and / or the water area environment while complying with legal standards and boundary values. In one example, a solvent meeting the feed water quality does not (substantially) contain the main components of circuit board / substrate manufacturing and consists simply of water, (non-heavy metal) salts, and (optionally) organic materials. In a preferred embodiment, a solvent meeting the feed water quality no longer (substantially) contains heavy metals. A solvent meeting the feed water quality can contain organic residues that can be removed in a wastewater treatment plant or, for example, by an activated carbon filter.

[0033] In an exemplary example, the solvent that meets the effluent water quality includes the effluent water quality within the wastewater treatment plant. The concentration of heavy metals can be 15 mg / L or less. In particular, the concentration of copper can be 0.5 mg / L or less (thus, for example, within the legal limit values of the Republic of Austria), and the solvent that meets the effluent water quality can be purified (for example, in an in-process wastewater treatment plant) so that the solvent can be supplied to the water area environment. This purification may be related to organic substance residues and not related to heavy metals. These can be simply removed, for example, by an activated carbon filter. For example, after purification, the CSB (chemical oxygen demand), which is an indicator of the concentration of organic compounds in the solvent that meets the effluent water quality, can be less than 300 mg / L, in particular, less than 75 mg / L (even more particularly, less than 65 mg / L). The CSB value can specify the amount of oxygen (in mg / L) required for the oxidation of oxidizable substances when oxygen is the oxidizing agent. For example, this boundary value is 75 mg / L by law in Austria. The CSB boundary value of the wastewater treatment plant can vary greatly and, in one example, is 300 mg / L.

[0034] In the context of this specification, the term "process control device" may in particular denote each device (or plurality of devices) suitable for performing process control, where the process relates (at least in part) to circuit board and / or substrate manufacturing. In particular, the process control device is adapted to control and respectively adjust (at least in part) the useful material cycle, where the production residues are fed back such that (heavy metal and / or acid) waste is not substantially generated. For this purpose, the process control device may in particular comprise a database (unit) and a data model unit, where the former stores the captured processed data, while the latter stores the intended desired process data. The process control device may in this way be coupled to a plurality of sensors and measuring devices in order to determine the actual parameters at different process stations. Furthermore, the process control device may comprise an arithmetic unit that compares the captured parameters with the desired parameters and, based thereon, determines and performs control operations. In a preferred embodiment, the process control device comprises a self-learning algorithm (AI) that can continuously improve the control and respectively adjustment of the process.

[0035] In the context of this specification, the term "substantially" may be interpreted to include negligible residues and / or contamination that cannot be removed any further with acceptable effort. These negligible residues and respective contaminations are (intentionally) undesirable in one embodiment but cannot be removed any further with reasonable effort. For example, a solvent having a drain water quality may substantially not contain heavy metals, which may indicate that negligible residues and respective contaminations may be present (for example, in the range of lower percentages, parts per thousand, or even ppm). Those skilled in the art will understand that these residues and / or contaminations are undesirable but nevertheless cannot be separated in a manner involving acceptable technical effort. In particular, the term "drain water quality" may indicate that there is "substantially" no heavy metal present since the heavy metal concentration consists only of residues / contaminations and is very low such that drainage in an aqueous environment is possible.

[0036] In the context of this specification, the term "(printed) circuit board" (PCB) may in particular denote a substantially plate-shaped component carrier (which may be flexible, rigid or semi-flexible), which is formed, for example, by applying pressure and / or by supplying thermal energy, by laminating a plurality of conductive layer structures with a plurality of electrically insulating layer structures. As a material preferred for PCB technology, the conductive layer structures are made of copper, while the electrically insulating layer structures may include resin and / or glass fiber, so-called prepreg or FR4 material. The different conductive layer structures can be connected to one another in a desired manner, for example, by forming through openings through the laminate by means of laser drilling or mechanical drilling and by filling them with a conductive material (in particular copper), whereby vias are formed there as through opening connections. In addition to one or more components that may be embedded in the printed circuit board, the printed circuit board is typically configured to receive one or more components on one or both of the mutually opposite surfaces of the plate-shaped printed circuit board. They can be connected to the corresponding main surfaces by soldering. These components can also be embedded. The dielectric part of the PCB may include a resin having a reinforcing structure (such as glass fiber or glass spheres).

[0037] In the context of this specification, the term "substrate" may in particular denote a small component carrier having substantially the same size as the components (in particular electronic components) mounted thereon (similar to a chip scale package (CSP)). In particular, the substrate may be a carrier for electrical connections or electrical networks, or a component carrier that is equivalent to a printed circuit board (PCB), but that has connections arranged with a clearly higher density in the horizontal and / or vertical direction. For example, the horizontal connections may be conductive paths, while the vertical connections may be, for example, via holes. These horizontal and / or vertical connections are arranged in the substrate and can be used to provide electrical and / or mechanical connections to a printed circuit board or an intermediate printed circuit board, in particular to an IC chip, for the components accommodated therein or not accommodated therein (such as dies). Thus, the term "substrate" also includes "IC substrates". The dielectric part of the substrate may comprise a resin having reinforcing particles (such as reinforcing spheres, in particular glass spheres).

[0038] The substrate or the interposer may consist of at least one glass layer (silicon (Si)) or an optically structurable or dry-etchable organic layer. As the organic material / organic layer, an epoxy-based build-up material (such as an epoxy-based build-up film), or a polymer compound such as, for example, polyimide, polybenzoxazole, or benzocyclobutene-functionalized polymer may be used.

[0039] In one embodiment, the component carrier is a stacked component carrier. In such an embodiment, the component carrier is a composite composed of a plurality of layer structures that are stacked and connected to each other by applying pressure and / or heat.

[0040] In one embodiment, at least one of the conductive layer structures includes at least one of the group consisting of copper, aluminum, nickel, silver, gold, palladium, magnesium, and tungsten. Typically, copper is preferred, but other materials and their coated versions, especially coatings with superconducting materials such as graphene, are also possible.

[0041] As used herein, the term "heavy metal" specifically may refer to metals having a density greater than 5.0 g / cm 3 (alternatively greater than 4.5 g / cm 3 ). This includes, for example, copper, nickel, cobalt, gold, silver, palladium, tungsten, tin, zinc, iron, lead, chromium, rhodium, cadmium, etc. According to this definition, aluminum, silicon, sodium, potassium, calcium, magnesium, etc. are not typically considered heavy metals, for example.

[0042] According to an exemplary embodiment, the present invention provides a cost-effective, environmentally friendly, and durable treatment of metal salt-containing etching waste solvents for circuit board and / or substrate manufacturing, which is possible in an efficient and robust manner (within the useful material cycle) when the ion exchange process is integrated between two closed-loop process cycles, where the first process cycle produces only metal elements and the second process cycle produces only purified water and / or metal-deficient salt concentrates.

[0043] Conventionally, waste and waste concentrates (rich in metal salts and acids) from circuit board and / or substrate manufacturing have been disposed of in a non-cost-effective, non-environmentally friendly, and non-durable manner. Furthermore, the waste from these etching processes is usually strongly acidic, and thus is pre-determined to be disposed of carefully as special waste. Therefore, a large-scale recovery (essential for recycling) is considered not possible in a cost-effective manner.

[0044] Surprisingly, it has been discovered that it is possible to economically recover (especially metal elements) from the metal salt-containing waste solvent. After a process that can save costs and labor, the recovered materials can be fed back into different process stages. For example, copper elements can be directly fed back into the plating process, while the separated acid can be fed into the etching process. In a preferred embodiment, the recovery can be carried out continuously, so that the waste generated from different process stages can be permanently treated, and the recycled materials can be directly provided to a single process stage.

[0045] Advantageously, flowing the stream through the treatment is carried out such that the high acid concentration does not interfere with the treatment process within the useful material cycle and the acid itself is maintained and fed back as part of it. Since these treatments can be water-intensive, the purified water can advantageously be fed back into different processes.

[0046] Metal salt-containing solvents from circuit board and / or substrate manufacturing have conventionally been regarded as waste that should be disposed of carefully (especially due to high concentrations of different metals and acids), but here, in complete contrast, it is explained that it is possible to economically and efficiently feed back the metals and acids within the same production process. [Exemplary Embodiment] According to an exemplary embodiment, the metal in the metal salt and the metal in the metal salt to be treated are the same metal. The metal is in particular at least one of the group consisting of copper, nickel, cobalt, tin, cadmium, magnesium, sodium, silver, and gold. Thereby, industrially relevant metals are efficiently recovered instead of being drained in a cost-intensive manner.

[0047] According to a further exemplary embodiment, the salts in the metal salt (e.g., copper sulfate) and the salts in the metal salt to be treated (e.g., copper chloride) are different salts. The salts have at least two of the group consisting of chlorides, sulfates, nitrates, and phosphates. This can have the advantage that multiple metal salts to be treated can be converted into the desired metal salt in the process in a flexible manner.

[0048] According to an exemplary example, copper in the form of copper chloride (as the metal salt to be treated) and hydrochloric acid as the acid result from an etching process as the solvent to be treated. High levels of chloride ions promote the uncontrollable formation of chlorine gas during recovery, e.g., during electrolysis. In addition, chloride ions can co-precipitate at the electrolysis electrodes, thereby negatively affecting the purity of the deposited copper.

[0049] According to a further exemplary embodiment, the first process cycle further comprises: i) flowing a further acid different from the acid (in particular, the further acid comprises at least one of the group consisting of sulfuric acid (H2SO4), hydrochloric acid (HCl), nitrous acid (HNO3), phosphoric acid (H3PO4)) through the ion exchange process, such that the further acid removes the metal from the ion exchange process (e.g., desorbing metal ions from an ion exchange resin) to provide the metal salt-containing solvent (e.g., copper sulfate concentrated solvent) (the further acid may also be referred to by the term regeneration solvent (comprising / consisting of the further acid)), ii) transporting the metal salt-containing solvent to a metal element recovery process and obtaining the metal element and the further acid from the metal salt-containing solvent (e.g., by electrolysis), and iii) feeding back the further acid (lacking the metal, the metal having been removed as a metal element) to the ion exchange process (as a regeneration solvent). has.

[0050] In this way, the acidic solvent (further acid) is circulated within the closed loop of the first process cycle. The acid of the acidic solvent does not need to be drained in a cost-intensive manner and is kept within the useful material cycle. Thus, the waste of the first process cycle is (substantially) only the metal elements which are actually useful recycled materials.

[0051] Also, the further acid / acidic solvent can be referred to by the term "regenerating solvent" of the ion exchange process. Such a regenerating solvent can have a high acid concentration (e.g., of sulfuric acid), in particular ≧ 100 g / L, more particularly ≧ 200 g / L, even more particularly ≧ 250 g / L.

[0052] In one example where the metal is copper, the solvent to be treated contains copper chloride, the further acid contains sulfuric acid, and the following reactions can occur:

[0053] CuCl2 (in the solvent to be treated) → 2Cl - (in the metal-deficient acidic solvent) + Cu 2+ (immobilized), and then, Cu 2+ (immobilized) + H2SO4 (in the further acid) → CuSO4 (in the metal salt-containing solvent) + 2H + (immobilized).

[0054] During regeneration, the Cu 2+ ions are thus exchanged by two H + ions, and a concentrated electrolyte of H2SO4 and CuSO4 is obtained, which can be directly used in electrolysis (metal-concentrated electrolyte).

[0055] In addition to the example described of exchanging copper chloride for copper sulfate, for example, the following salt exchange reactions can occur (each with the corresponding acid) (and can be realized in both directions depending on the extract):

[0056] NiCl2 + H2SO4 ←→ NiSO4 + 2HCl NiCl2 + 2HNO3 ←→ Ni(NO3)2 + 2HCl CoCl2 + H2SO4 ←→ CoSO4 + 2HCl CoCl2 + 2HNO3 ←→ Co(NO3)2 + 2HCl 3CoCl2 + 2H3PO4 ←→ Co3(PO4)2 + 6HCl SnCl2 + H2SO4 ←→ SnSO4 + 2HCl SnCl2 + 2HNO3 ←→ Sn(NO3)2 + 2HCl CdCl2 + H2SO4 ←→ CdSO4 + 2HCl CdCl2 + 2HNO3 ←→ Cd(NO3)2 + 2HCl 3CdCl2 + 2H3PO4 ←→ Cd3(PO4)2 + 6HCl MgCl2 + H2SO4 ←→ MgSO4 + 2HCl MgCl2 + 2HNO3 ←→ Mg(NO3)2 + 2HCl 3MgCl2 + 2H3PO4 ←→ Mg3(PO4)2 + 6HCl 2NaCl + H2SO4 ←→ Na2SO4 + 2HCl NaCl + HNO3 ←→ NaNO3 + HCl 3NaCl + H3PO4 ←→ Na3PO4 + 3HCl According to a further embodiment, the metal element recovery process comprises an electrolysis process, the metal salt-containing solvent is similar to the metal-concentrated electrolyte entering the electrolysis process, and the further acid is similar to the metal-deficient electrolyte exiting the electrolysis process. This can provide the advantage that a solvent suitable for electrolysis is provided without additional effort. The metal element can be recovered by electrolysis to a purity of about 99.999%, which may be necessary for feedback to the manufacturing process.

[0057] According to a further embodiment, the metal salt-containing solvent is applied as a metal-concentrated electrolyte, either alone or in combination with other metal salt-containing solvents from circuit board and / or substrate manufacturing. The treatment of such a stream (or all streams) (and the adjustment of each composition) may comprise at least one of the following features: i) Filtering organic constituents from the metal salt-containing solvent (electrolyte) by a filter, preferably an activated carbon filter. ii) Separating the foreign metal (especially iron) from the metal salt-containing solvent (electrolyte) by means of a further ion exchanger. This can have the advantage that the metal salt-containing solvent is purified as an electrolyte while the foreign metal is obtained as a raw material for other process steps. iii) Separating an acid (especially sulfuric acid) from the metal salt-containing solvent (electrolyte). This allows for selective adjustment (readjustment), and the separated substances are at least partially reused within the process.

[0058] According to a further embodiment, the metal element is recovered from the metal salt-containing solvent in the reaction cell (especially by electrolysis). The metal element of the metal salt-containing solvent (e.g., copper) should be recovered in the reaction cell in a (very) pure form for resupply to the process for manufacturing circuit boards and / or substrates. In particular, the obtained metal element is fed back into the plating process.

[0059] According to a further embodiment, the second process cycle further comprises: i) Passing the solvent to be treated through the ion exchange process, where the solvent to be treated is separated into the metal that remains in the ion exchange process after separation (e.g., adsorbed by an ion exchange resin) and a metal-deficient (hydrochloric acid) acidic solvent. ii) Treating the metal-deficient acidic solvent in a water treatment process, as a result of which purified water is obtained, and using the purified water a) Feeding the purified water back to the ion exchange process. b) Feeding the purified water back to a further circuit board and / or substrate manufacturing process (e.g., membrane dialysis, dilution process, washing water treatment process, etc.). c) Draining the purified water as water that meets the effluent water quality. using it according to at least one of the group consisting of: and having.

[0060] This can provide the advantage that strongly acidic solvents (which were conventionally drained in a cost-intensive and environmentally unfriendly manner) are efficiently processed into purified water. The described process can be very water-intensive, so it may be highly desirable to continuously recycle the treated water.

[0061] The solvent (water) that meets the drainage water quality no longer (substantially) contains the main components (especially heavy metals) of circuit board / substrate manufacturing and consists simply of water, salts, and organic materials.

[0062] According to a further embodiment, the water treatment process includes a membrane filtration process, particularly a reverse osmosis process, the permeate includes the purified water, and the concentrate includes a salt concentrate. This can provide the advantage that established industrial processes can be directly implemented to produce purified water that can be recycled within the process.

[0063] The term "membrane filtration" can refer, in the context of this specification, to an established water purification process that uses a semi-permeable membrane to separate ions, unwanted molecules, and larger particles from water. Examples of membrane filtration can include microfiltration, nanofiltration, and reverse osmosis. In reverse osmosis, the applied pressure can be used to overcome the osmotic pressure. Thereby, reverse osmosis can remove a variety of dissolved and suspended chemical and biological species (mainly bacteria) from water. The reverse osmosis process can produce two products: a permeate (purified water) and a concentrate (a salt concentrate, especially a metal salt).

[0064] According to a further embodiment, the second process cycle further has: a step of feeding back the salt concentrate to the ion exchange process, as a result of which the metal of the salt concentrate remains within the ion exchange process; and a step of thereby providing the metal-deficient salt concentrate.

[0065] The salt concentrate is, in particular, a metal salt concentrate that still contains (heavy) metals from the etching process. Therefore, the metal salt concentrate may not be suitable for being drained. As a result, and in order to further increase the yield of metal elements, the salt concentrate is transported (preferably diluted, in particular diluted with purified water and / or washing water) so as to return to the ion exchange process. Here, the metal can be removed again from the diluted metal salt concentrate (e.g., adsorbed by an ion exchange resin), and in particular after a plurality (e.g., 3, 7, etc.) of cycles within the second process cycle, the metal salt concentrate becomes a metal-deficient salt concentrate.

[0066] According to a further embodiment, the metal-deficient salt concentrate contains (substantially) no heavy metals (in particular, contains only salts and optionally water / organics) and can be drained in a low-cost and environmentally friendly manner.

[0067] According to a further embodiment, the method further comprises the step of adding a base (e.g., sodium hydroxide) to the metal-deficient acidic solvent, where the base and the acid of the metal-deficient acidic solvent form the salt of the salt concentrate (e.g., sodium chloride). This can provide the advantage that the strong acid is neutralized in a cost-effective manner.

[0068] According to a further embodiment, the ion exchange process includes the step of applying an ion exchanger, in particular where the ion exchanger has an ion exchange resin. The ion exchanger can be realized, for example, as a column filled with an ion exchange material or as a membrane through which the solution flows. The ions to be exchanged are bound and adsorbed respectively in the ion exchange material. In one example, the ion exchanger includes a selective ion exchange resin, and further, in particular, includes a bifunctionalized ion exchange resin.

[0069] In one embodiment, the carrier material of the ion exchange resin of the ion exchanger comprises polystyrene. In particular, it comprises two functional groups (difunctional ion exchange resin), for example, i) phosphonic acid residues and ii) sulfonic acid residues. The first group of acids has a higher pK value than the second group of acids. The acid with the higher pK value is a weaker acid than the acid with the lower pK value (strong acid) and is less prone to thermal decomposition. Thereby, during regeneration, the foreign metal can be more easily desorbed by the resin.

[0070] According to one embodiment, surprisingly, it has been found that the use of a special ion exchange resin having exactly two functional groups enables the (efficient) desorption of metals (especially iron).

[0071] In an exemplary example, the ion exchanger is constructed in two stages. The first ion exchanger (upstream) may comprise a strongly acidic ion exchange resin for adsorbing most of the metal. The second ion exchanger (downstream) may comprise a weakly acidic ion exchange resin for adsorbing the remaining metal (especially to such an extent that the metal-deficient acidic solvent meets the effluent water quality from the perspective of heavy metal content).

[0072] In an exemplary example, the strongly acidic ion exchange resin can adsorb a certain (any) cation applied to the resin. Thus, the initial ion exchange resin does not have to be a selective ion exchange resin. However, the strongly acidic ion exchange resin can have a significantly increased absorption capacity, which can be considered advantageous. In cases where the amount of (different) cations is not significant, such lack of selectivity can work well. The weakly acidic ion exchange resin can selectively adsorb the remaining amount of copper. In subsequent process steps, the pH value can be increased. Otherwise, sodium ions can be introduced into the process, which further contaminates the electrolyte (also, the capacity of the initial ion exchange resin decreases as sodium adsorbs onto the resin).

[0073] According to a further embodiment, the ion exchange process has a step of applying liquid / liquid extraction. In a preferred embodiment, the liquid / liquid extraction can be carried out using a hydrocarbon diluent having a high flash point as the extraction solvent (hydrocarbon-based ion exchange solvent). Such a hydrocarbon diluent can form water-insoluble complexes with various metal cations, such as copper. During the ion exchange process, the following reaction can occur: 2RH (org) +Cu 2+ (aq) →R2Cu (org) +2H + (aq) 。

[0074] Thereby, the hydrocarbon diluent can act similarly to an ion exchange resin in that it reversibly absorbs cations (especially copper) by an ion exchange reaction. Further, the cation can then also be exchanged by two H + ions.

[0075] In one example, a concentrated and de-acidified solvent stream to be treated (e.g., containing copper chloride) will be (ion) extracted using a high flash point hydrocarbon diluent. Although both liquids are immiscible with each other, during the ion extraction / exchange process, these two liquids are brought into intimate contact with each other, for example, by mixing (within the ion exchange process / system). By mixing, the two immiscible liquids are brought into intimate contact with each other in such a way that ion exchange (transfer) occurs at the liquid / liquid interface. As a result, the cation (copper) will then be present within the high flash point hydrocarbon diluent solvent, while the anion (e.g., chloride ion) will remain in the newly obtained metal-deficient acidic solvent. Since these two solvents are immiscible with each other, they will be separated after some time has passed. This can be done, for example, using a settling tank (which can be part of the ion exchange process). The high flash point hydrocarbon diluent (concentrated with cations) can then be further regenerated (''stripped'') using a further acid (especially sulfuric acid), thereby enabling the production of a metal salt-containing solvent (e.g., an electrolyte having copper sulfate). Since the metal salt-containing solvent and the high flash point hydrocarbon diluent (deficient in cations) are also immiscible with each other, the metal salt (copper sulfate) can be easily separated, and the high flash point hydrocarbon diluent (hydrocarbon extraction solvent) can be reused in a manner similar to an ion exchange resin. An exemplary example of the high flash point hydrocarbon diluent (hydrocarbon extraction solvent) can be a mixture of 5-nonylsalicylaldoxime and 2-hydroxy-5-nonylacetophenone oxime in a 1:1 ratio.

[0076] According to a further embodiment, the step of providing the solvent to be treated is integrated within a third (closed) loop and a third process cycle that (substantially) produces no waste. In this way, the acidic waste from the etching process can be efficiently recycled within the same circuit board / substrate manufacturing.

[0077] According to a further embodiment, the third process cycle further: i) removing the acid from the solvent to be treated by membrane dialysis to provide a solvent to be treated lacking acid (weakened acidity) and an acidic diffusate (in particular, further concentrating the acidic diffusate within an acid concentration process to obtain an acid-concentrated diffusate), and ii) feeding back the acidic diffusate and / or the acid-concentrated diffusate to the etching process to regenerate the solvent to be treated (again). It has.

[0078] Thereby, acidic waste (which is difficult to drain and cost-intensive) is not generated. Rather, the acid from the etching process can be separated from the solvent to be treated and fed back to the etching process.

[0079] The acidic diffusate (after the membrane dialysis step for treatment) containing only a very low concentration of metal salts can have the acid concentrated (along with a further separation stream of another process), for example, using gas adsorption, before being transported back to the etching process. Alternatively, the acidic diffusate can be fed to central treatment (such as wash water). While the acid can be reused in the circuit board and / or substrate manufacturing process, the metal salts can be concentrated (for example, via wash water treatment) and recovered again. In another embodiment, the acid is used as a regenerated acid for the production of iron chloride, FeCl3.

[0080] According to a further embodiment, the step of providing the solvent to be treated has the step of performing a hydrogen peroxide (H2O2) removal process. The solvent to be treated may contain oxidants such as hydrogen peroxide from an etching process. These oxidants can attack the membranes of membrane dialysis and / or ion exchange resins. The reduction and / or removal of the oxidant can be done chemically, thermally, electrically, or using a catalyst. Hydrogen peroxide removal may include the following chemical reaction: 2H2O2 → 2H2O + O2. For example, thermal decomposition occurs at about 50 - 60 °C. The catalytic reaction can be carried out, for example, using iron(III) chloride (FeCl3) as a catalyst and an activated carbon filter, or an enzyme called catalase can be used to induce the removal reaction. Electrolysis can occur as soon as a potential (voltage) is applied. Further, hydrogen peroxide can be chemically removed using any reducing agent such as sodium bisulfite.

[0081] According to a further embodiment, the treatment is carried out continuously. This can have the advantage that continuous concentration of the solvent to be treated occurs and the ion exchanger can be regenerated particularly efficiently.

[0082] According to a further embodiment, the method further comprises the step of diluting the solvent to be treated (especially in a mixing reactor) before the ion exchange process. The acid-deficient solvent to be treated may still have a relatively high acid concentration. Thus, a further dilution step may be advantageous / necessary. The step of diluting may further have the step of diluting using (treated) wash water and / or purified water from circuit board and / or substrate manufacturing. By diluting the acid-deficient solvent, the pH value can increase, which further increases the holding capacity of the ion exchange process. Thus, more copper ions can be extracted / adsorbed by the ion exchange process.

[0083] According to a further embodiment, about 40% of HCl can be saved during the described process.

[0084] According to a further embodiment, the output stream (which is the product produced, the waste) can be hydrochloric acid (about 10%), water meeting the drainage water quality, the concentrate of reverse osmosis (especially metal-deficient salts), and 99.999% pure copper.

[0085] The aspects defined above, and further aspects of the present invention, will be apparent from the examples of embodiments described hereinafter and will be described with reference to these examples of embodiments.

Brief Description of the Drawings

[0086]

Figure 1

[0087]

Figure 2

Figure 3

Figure 4

[0088]

Figure 5

[0089] The illustrations in the figures are schematic. In different figures, similar or identical elements are provided with the same reference numerals.

Mode for Carrying Out the Invention

[0090] FIG. 1 shows an overview of streams 1 to 7 in the production of a circuit board and / or a substrate, for example in an industrial plant 60, according to one embodiment of the present invention. The method for manufacturing a circuit board and / or a substrate is such that the generated processing residues 11, 21, 31 are flowed in a useful material cycle in three main partial streams 1, 2, 3 (and in particular at least partially as the total stream 4) and three main separation streams 5, 6, 7 (in particular containing acid residues), and feedback (and respectively recycling) is carried out, so that in the (shown) operating state of the manufacturing method, only the solvent 350 (and / or the metal-deficient salt concentrate 186b) that (substantially) meets the drainage (feed water) water quality is generated as waste (in other words: the substantially only waste leaving the manufacturing process). In other words, the solvent 350 and / or the metal-deficient salt concentrate 186b that meets the drainage water quality no longer (substantially) contains the main components of the circuit board / substrate manufacturing (in particular does not contain heavy metals), and consists merely of (at most) water, salts, and organic materials. In the (shown) operating state, (substantially) only water 352 and energy need to be supplied to the manufacturing method (the generated acid residues are also (substantially) fed back into the useful material cycle). Therefore, substantially only such main components (in particular heavy metals such as copper) are supplied to the manufacturing method and leave the manufacturing method as components of the completed printed circuit board and / or substrate. In principle, in the useful material cycle described, more than 95%, in particular more than 98%, of the heavy metal residues (for example copper residues) can be fed back. In an exemplary embodiment of the useful material cycle, at least 80% (in particular at least 85%, more particularly at least 90%) of the separated hydrochloric acid is fed back, and at least 70% (in particular at least 75%, more particularly at least 80%, even more particularly at least 90%, still more particularly at least 95%) of the required sulfuric acid is generated within the method. Therefore, the main components leaving the manufacturing method as waste are not (substantially) added to the manufacturing process. In fact, in principle, such waste does not (substantially) occur.

[0091] The generated processing residues 11, 21, 31, and their respective waste concentrates are shown as metal salt-containing solvents to be treated. In exemplary embodiments, they can include, inter alia: copper, copper sulfate, copper chloride, iron, nickel, gold, hydrochloric acid, and sulfuric acid. The metal salt-containing solvents 11, 21, and 31 to be treated are each processed in the corresponding processing processes 100, 200, 300, and then supplied to the recovery process 400 as partial streams 1, 2, 3 each containing the treated metal salt-containing solvents 10, 20, 30. After treatment, the recovered metal elements 50 are finally supplied back to the manufacturing process (arrows 52 and 54). Below, a schematic overview of partial streams 1-7 in the useful material cycle is given. Further below, a detailed description of the processes forming the central aspects of this specification is provided.

[0092] The first partial stream 1 includes the first treated metal salt-containing solvent 10 from the etching process 150 of circuit board and / or substrate manufacturing, which is processed in the first processing process 100. The first process 100 can be regarded as a main aspect of this specification. The first treated metal salt-containing solvent 10 (substantially free of the metal salt to be treated) is obtained from the solvent 11 to be treated from the etching process 150 as an etching waste solvent. The solvent 11 to be treated contains the metal salt to be treated (e.g., copper chloride) and an acid (e.g., hydrochloric acid). The treatment 100 includes removing the acid 15 by (preferably multi-stage) membrane dialysis 110, 120 and performing an ion exchange process 145 (especially a multi-stage ion exchange process). In the multi-stage membrane dialysis 110, 120, the first acid-containing diffusate 116 is generated. The second acidic diffusate 126 can be directly provided back to the etching process 150 (preferably concentrated).

[0093] In the ion exchange process 145, the metal salt to be treated (e.g., copper chloride) is exchanged by a metal salt (e.g., copper sulfate), and the metal salt-containing solvent 10 (e.g., copper sulfate) is thereby obtained from the solvent to be treated 11 (e.g., copper chloride). The metal salt-containing solvent 10 is supplied as the first partial stream 1 to the metal element recovery process 400 (see the following description). Further, a metal-deficient acidic solvent 136 (e.g., hydrochloric acid) is generated during the ion exchange process 145. The metal-deficient acidic solvent 136 can be (at least partially) flowed as the first separation stream 5 to the washing water treatment process 300 (see the following description). A further portion of the metal-deficient acidic solvent 136 is flowed through a membrane filtration process implemented as the reverse osmosis process 185 (especially after being supplied by a base (e.g., sodium chloride) 187). The reverse osmosis process 185 produces a permeate (e.g., purified water 188) that is flowed back to the ion exchange process 145 (via the mixing reactor 140) or to another one of the circuit board manufacturing processes of the manufacturing plant 60. Further, the purified water 188 can be drained as water 350 that meets the drained water quality (i.e., contains only water and a small amount of salts and organic substances). The reverse osmosis process 185 further produces ii) a salt concentrate 186a of salts and metal residues. The salt concentrate 186a can be diluted (189) and flowed through the ion exchange process 145 again. Thereby, the diluted salt concentrate 186a becomes a salt concentrate 186b lacking in metal (especially heavy metals) (i.e., containing only salts and a small amount of organic substances), and the salt concentrate 186b can be drained either as a concentrate or in a diluted form. Thus, treating the waste solvent 11 from the etching process 150 produces only the purified water 188 (water 350 that meets the drained water quality) and / or the metal-deficient salt concentrate 186b. All other generated products can be recycled in the circuit board and / or substrate manufacturing process.

[0094] Part 2 Stream 2 includes the second processed metal salt-containing solvent 20 from the plating process 250 for circuit board and / or substrate manufacturing. The second processed metal salt-containing solvent 20 (substantially free of iron) is obtained from the iron and metal salt-containing solvent 21 from the plating process 250. Process 200 includes separating iron from the iron and metal salt-containing solvent 21 by an ion exchanger. When regenerating the ion exchanger, a second acid-containing diffusate is generated and can be supplied as the second separation stream 6 to the wash water treatment process 300.

[0095] Part 3 Stream 3 includes the third processed metal salt-containing solvent 30 from the wash water and the respective wash water mixtures 31 for circuit board and / or substrate manufacturing. The third processed metal salt-containing solvent 30 is obtained in the third treatment process 300 using an ion exchanger, and the metal salt in the processed metal salt-containing solvent 30 is concentrated compared to the wash water mixture 31. Also, it should be added here that the described wash water treatment process 300 can be implemented within or coupled to the ion exchange process 145. In this case, the wash water (mixture) 31 is mixed in the mixing reactor 140 with the solvent to be treated 12, and both are subject to the ion exchange process 145 and the respective first process cycle 170 (and optionally also the second process cycle 180).

[0096] Sub-streams 1, 2, 3 can be (at least partially) combined into the total stream 4 (see stage 405), or can also be treated individually. Process 400 includes recovering the metal element 50 (e.g., copper element) from the metal salt-containing solvent 40 in an (electrolytic) reaction cell 400. Continuously adjusting the composition of the metal salt-containing solvent 40 as an electrolyte includes separating the acid by membrane dialysis, where a third acid-containing diffusate 446 is generated. Alternatively, the diffusate 446 can be used for the regeneration of the ion exchanger for treating wash water (see the third separation stream 7).

[0097] A further possibility is that no acid is removed from the electrolyte 10. Instead, the used electrolyte 175 can be used as a regenerant.

[0098] As the acid concentration in the electrolyte 400 increases while the copper ion concentration decreases, the used electrolyte 175 becomes strongly acidic, enabling better desorption of copper ions from the ion exchange process 145. In addition, the copper that has not yet been deposited is retained within the process cycle. Thus, the acid concentration in the electrolyte 10 is increased and it can be further used as a regenerant. In addition, by not using further membrane dialysis, water and energy can be conserved.

[0099] Also, the metal (especially copper) remains in the useful material cycle and can thus be removed almost completely from the metal salt-containing solvent. This has the advantage that a further treatment step by membrane dialysis can be omitted. The very pure metal 50 obtained is further suitable for being fed back again into the etching process (see arrow 52) and / or into the plating process 250 (see arrow 54).

[0100] The first separation stream 5 results from the first treatment process 100 and contains the acidic diffusate 136. The second separation stream 6 results from the second treatment process 200 and contains the second acid-containing diffusate 236. The third separation stream 7 results from the treatment process of the total stream 4 and contains the third acid-containing diffusate 446. The separation streams 5, 6, 7 each contain a low concentration of metal salt (e.g., copper sulfate), each at a concentration lower than the concentration of the metal salt in the third partial stream 3. The separation streams 5, 6, 7 are each (at least partially) combined into the solvent to be treated 31 and the mixture of washing water (total separation stream). Also, further washing water of the manufacturing method can be injected here. The solvent to be treated 31 is treated as described above by the third treatment process 300, and the concentration is clearly increased for recovery 400.

[0101] Also, it should be added here that the described wash water treatment process 300 can be implemented within or coupled to (see above) the ion exchange process 145.

[0102] FIG. 2 shows in detail an exemplary embodiment of a method for treating an etching waste solvent from circuit board and / or substrate manufacturing. The etching waste solvent is provided as the solvent 11 to be treated from the etching process 150 and contains a metal salt to be treated (e.g., copper chloride) and an acid 15 (e.g., hydrochloric acid). The solvent 11 to be treated may contain a high concentration of hydrogen peroxide from the etching solution, which may interfere with the following treatment and damage the membranes of the membrane dialysis 110, 120. Therefore, within a hydrogen peroxide removal process 160, e.g., catalytic decomposition, thermal decomposition, chemical decomposition, or electrolysis, the hydrogen peroxide concentration is reduced or the hydrogen peroxide is removed. After the hydrogen peroxide removal 160, the solvent 11 to be treated is passed through a two-stage membrane dialysis 110, 120 (see FIGS. 3 and 4 for detailed description).

[0103] The membrane dialysis 110, 120 is supplied by demineralized water 352 which may contain purified water 188 that can be injected into the process (from the outside) and / or generated and fed back later within the process. In order to obtain the solvent 12 to be treated with reduced acidity, during the membrane dialysis 110, 120, the acid 15 is substantially removed from the solvent 11 to be treated. Here, the acid 15 is part of an acidic diffusate 126 (acid concentration about 10%), and the acidic diffusate 126 can be fed back to the etching process 150. Since the etching process 150 can apply an etching solvent having an acid concentration of about 30%, the acidic diffusate 126 is optionally concentrated in an acid concentration process 128. Next, the concentrated acidic solvent 129 can be fed back to the etching process 150. Thereby, the etching process 150, the hydrogen peroxide removal 160, and the membrane dialysis 110, 120 (optionally also the acid concentration process 128) can form a third process cycle 190 configured as a third closed loop that (substantially) produces no waste (since the acid 15 is transported within a closed loop).

[0104] The treatment target solvent 12 with weakened acidity is injected into the mixing reactor 140, where the treatment target solvent 12 with weakened acidity can be mixed with other metal salt solvents. For example, the washing water 31 can be mixed with the treatment target solvent 12 with weakened acidity, where the washing water 31 can contain small amounts of metal salts (such as copper sulfate) from various processes in the circuit board manufacturing process. Further, the mixing reactor 140 is applied to dilute the treatment target solvent 12 with weakened acidity (especially when it still contains a significant acid concentration). The dilution can be carried out using, for example, the washing water 31, the external water 352, or the feedback purified water 188. From the mixing reactor 140, the (mixed) treatment target solvent 12 is provided to the ion exchange process 145.

[0105] The ion exchange process 145 can include an ion exchanger (such as an ion exchanger having an ion exchange resin) or a liquid-liquid ion exchange process. When the diluted treatment target solvent 12 flows through the ion exchange process 145, metal ions (such as copper ions) remain (at least partially) within the ion exchange process 145. For example, the copper ions are adsorbed by the ion exchange resin. After flowing through the ion exchange process 145 (where the metal remains), a metal-deficient acidic solvent 136 is obtained. This solvent 136 is significantly deficient in metal, but it can still contain heavy metals (including copper). Therefore, the metal-deficient acidic solvent 136 does not have the quality of wastewater and further flows to the water purification process 185.

[0106] The ion exchange process 145 is integrated within a first process cycle 170 configured as a first closed loop. As a result, a further acid (such as sulfuric acid) 175, different from the acid 15, flows through the ion exchange process 145. Consequently, the further acid 175 is used to provide the metal salt-containing solvent 10 (for example, to remove copper ions from the ion exchange resin and replace them with H +By exchanging ions, the metal removed from the ion exchange process 145 is removed. Further, the additional acid 175 can be regarded as a regeneration solvent containing / consisting of the additional acid 175. In the exemplary example described, the metal (copper) from the ion exchange process 145 and the salt (sulfate) from the additional acid result in a metal salt (copper sulfate) containing solvent 10. The metal salt containing solvent 10 is transported to the metal element recovery process 400 (see the above description), and from the metal salt containing solvent 10, the metal element 50 (for example, the copper element after electrolysis) and again the additional acid 175 (regeneration solvent) are obtained. Next, to close the loop, the additional acid 175 is fed back to the ion exchange process 145 to remove the (immobilized) metal again.

[0107] In one example, the additional acid 175 may still contain copper as copper sulfate. Therefore, this additional acid 175 contains an electrolyte, where the copper concentration is too low to achieve the desired copper deposition rate. In addition, the acid concentration continuously increases during electrolysis 400. Thus, the additional acid 175 has a low pH value and is perfectly suitable for recovering the copper adsorbed on the ion exchange process 145.

[0108] As described above, the metal element recovery process 400 preferably comprises an electrolysis process, where the metal salt containing solvent 10 resembles the metal enriched electrolyte entering the electrolysis process. After the metal element 50 is obtained, the metal deficient electrolyte exits the electrolysis process, and the metal deficient electrolyte substantially contains the additional acid 175.

[0109] The ion exchange process 145 is further integrated within a second process cycle 180 configured as a second closed loop. The second process cycle 180 includes a water purification process 185 through which the metal-deficient acidic solvent 136 flows. From this process, purified water 188 is obtained which can be fed back (via the mixing reactor 140) to the ion exchange process 145 within the second process cycle 180. Additionally, or alternatively, the purified water 188 is fed back to a further circuit board and / or substrate manufacturing process (such as membrane dialysis 110, 120, wash water treatment process 300), or is discharged as water 350 that meets the effluent water quality. In one embodiment, a strong base 187 (such as sodium hydroxide) is added to the metal-deficient acidic solvent 136. Next, the base 187 and the acid (hydrochloric acid) of the metal-deficient acidic solvent 136 form a salt (such as sodium chloride).

[0110] Preferably, the water treatment process 185 comprises a reverse osmosis process, in which the permeate 185a contains purified water 188 and the concentrate 185b contains a salt concentrate 186a. As described above, the salt concentrate 186a also has a high salt concentration (e.g., sodium chloride) from the acid 15 and heavy metals (still from the etching process 150). The salt concentrate 186a is fed back to the ion exchange process 145 within the second process cycle 180, such that the (heavy) metals from the salt concentrate 186a remain within the ion exchange process 145 in the same manner as the metals from the solvent to be treated 12 (e.g., adsorbed by an ion exchange resin). This situation provides a metal-deficient salt concentrate 186b, which can be discarded either as a concentrate or in a diluted form. The metal-deficient salt concentrate 186b is substantially free of heavy metals (and contains only salts and optionally water and organics). The salt concentrate 186a can be diluted in a dilution process 189 and fed back to the ion exchange process 145 as a separate stream. The salt concentrate 186a can be diluted in the mixing reactor 140 (e.g., using wash water 31, external water 352, purified water 188) and / or mixed with the solvent to be treated 12. Additionally or alternatively, the salt concentrate 186a can be at least partially diluted using purified water 188 and flowed back to the ion exchange process 145 as a unified stream. The described process can be carried out continuously or batchwise.

[0111] Figure 3 shows an example of providing the solvent 12 to be treated with weakened acidity using membrane dialysis 110 and 120 according to an exemplary embodiment of the present invention. In the following embodiments, mainly copper is used as an exemplary example. However, the same also applies to further metals such as nickel, cobalt, rhodium, tin, cadmium, magnesium, sodium, silver, gold, etc. These can form metal salts with acids (e.g., hydrochloric acid, sulfuric acid, nitrous acid, phosphoric acid). According to an exemplary embodiment, from the etching process 150, copper in the solvent 11 to be treated occurs in the form of copper chloride (as the metal salt to be treated), and hydrochloric acid occurs as acid 15. High levels of chloride ions promote the uncontrollable formation of chlorine gas during recovery, for example, during electrolysis. In addition, chloride ions can co-precipitate at the electrodes, negatively affecting the purity of the deposited copper. Therefore, in the first treatment process 100, copper chloride is converted to copper sulfate while the free acid 15 is separated. The metal salt-containing solvent 11 to be treated is collected in the overflow tank of the etching process 150 and supplied as dialysis fluid 11 to the first membrane dialysis 110. Further, demineralized water is supplied to the membrane dialysis 110 via the first diffusate feed 113. The membrane 112 can include, for example, a wound membrane or a plate-shaped membrane. The membrane 112 is semi-permeable, and anions (e.g., chloride) can pass through (anion membrane), while cations (e.g., Cu 2+ ) cannot pass through. The membrane dialysis 110 has a throughput in the range of 0.5 - 5 L / hm 2 (in particular, 1 - 2 L / hm 2 ). For the membrane dialysis described below, the same membrane can be used respectively, or (preferably) different membranes can be used (e.g., according to which (etching) process each metal salt-containing solution results from). The anion membrane can be functionalized with, for example, bromine (Br - ), where the carrier material can be, for example, PET or PVC. In certain cases, the metal salt-containing solution can contain hydrogen peroxide (H2O2). In this case, preferably, an oxidation-resistant membrane based on, for example, PEEK (polyetheretherketone) can be used.

[0112] By the first membrane dialysis 110, the first portion of the acid 15a is removed from the solvent 11 to be treated, thereby obtaining a first dialysis solution 115 having a first concentration of the metal salt to be treated and a first diffusate 116 containing the first portion of the acid 15a. The first diffusate 116 further contains the metal salt to be treated at a second concentration (lower than the first concentration). This is due, in particular, to the fact that when the cations form complexes and aggregates (e.g., copper-chlorine complexes) respectively, a part of the cations still passes through the membrane 112. Without wishing to be bound by any particular theory, it is currently considered that the formation of such aggregates can occur when the concentration of cations in the solution increases.

[0113] Thereafter, the first diffusate 116 undergoes a second membrane dialysis 120. The first diffusate 116 is supplied to the second membrane dialysis 120 as a dialysis solution feed. Demineralized water is used as the second diffusate feed 123. The second portion of the acid 15b is removed from the first diffusate 116 to obtain a second dialysis solution 125 having a third concentration (lower than the second concentration) of the metal salt to be treated and a second (acidic) diffusate 126 containing the second portion of the acid 15b. The first diffusate 116 further contains the metal salt to be treated at the second concentration. The second diffusate 126 contains the metal salt to be treated at a fourth concentration lower than the third concentration. The concentration of the cations of the metal salt to be treated in the first diffusate 116 is clearly lower than the cation concentration in the dialysis solution feed 11. Therefore, aggregates are no longer substantially formed, and it is considered that only a negligible amount of cations diffuse through the membranes 112, 122. For this reason, preferably, exactly two membrane dialysis stages 110, 120 are carried out. Thereby, in an advantageous manner, a high concentration of the metal salt can be achieved, while at the same time, the amount of liquid used does not become excessive.

[0114] The second diffusate 126, which contains a negligible amount of the metal salt to be treated but has a high acid concentration, is collected in the etching process collection gutter and then provided again to the etching process 150 for circuit board and / or substrate manufacturing. In particular, the second diffusate 126 is treated first. The first dialysate 115 and the second dialysate 125 are combined to provide the solvent 12 to be treated containing the concentrated and acid-weakened (or substantially acid-free) metal salt.

[0115] FIG. 4 shows again an example of providing the acid-weakened solvent 12 to be treated using membrane dialysis 110, 120 according to an exemplary embodiment of the present invention, and further illustrates the ion exchange process 145 described in detail in FIG. 2. Further, a first process cycle 170, a second process cycle 180, and a third process cycle 190 are shown (see the description of FIG. 2 for details).

[0116] FIG. 5 shows a process control device 600 for adjusting (and respectively controlling) at least a part of the method (and respectively that of the industrial plant 60) described above according to an embodiment of the present invention. In the example shown, the process control device 600 is implemented in the first treatment process 100 to provide the first metal salt-containing solvent 10 from the etching process 150 from circuit board and / or substrate manufacturing. In this way, the process control device 600 can also be implemented in further processes (and respectively methods) described above.

[0117] The process control device 600 includes a database 610 for capturing at least one process parameter 611 from an i) executing (operating state) process (the first processing process 100 in the example shown). In an exemplary embodiment, it is shown that process parameters (values and / or ranges) 611 are captured (e.g., by sensors) at all processing stages and supplied to the database 610. Thus, the process parameters constitute the "actual" values (e.g., HCl concentration, copper concentration, pressure difference, etc.). The process control device 600 further includes: ii) a data model unit 620 adapted to store at least one predetermined process parameter 621 (value and / or range). In the example shown, a plurality of process parameters by one or more data models are provided in the data model unit 620 for different process stages. Thus, these predetermined process parameters 621 constitute the "target" values. The process control device 600 further includes: iii) an arithmetic unit 630 (e.g., a single (separate) unit or a plurality of units) adapted to a) compare the captured process parameter 611 (and respectively a plurality of these parameters) with the predetermined process parameter 621 (and respectively a plurality of these parameters) (e.g., compare the "actual" value with the "target" value), b) determine a control operation 631 based on the result of the comparison (e.g., actively balance the difference between the "actual" value and the "target" value), and c) perform the determined control operation 631 (e.g., adapt the flow rate).

[0118] According to an exemplary embodiment of a (software-based) process control device 600, a database 610 collects data (process parameters 611) from the processes being executed, accesses the values (process parameters 611) from the previous process stages respectively, and thus stores all the "actual" values. Each of the mutually dependent data models and the plurality of data models (stored in the data model unit 620 in the form of a database for example) includes, inter alia, "target" values (and "target" ranges), and optionally also includes relationships and variables (for example, data model 621 as a reference value / reference model used for verification of the "actual" value 611). The arithmetic unit 630 compares the "actual" values with the "target" values (performs an arithmetic stage based on the data model 621 combined with the "actual" values 611 respectively), and then sets an operation (control operation 631) corresponding to the comparison result (for example, the "actual" value corresponds to the "target" value, the "actual" value deviates from the "target" value, the "actual" value meets a specific criterion, etc.). The determined control operation 631 may include at least a part of the method steps as described above.

[0119] According to an exemplary embodiment, the arithmetic unit 630 includes a self-learning algorithm (AI) 625 for comparison and / or determination (e.g., implemented by a neural network). The self-learning algorithm 625 is adapted to automatically perform the determined control operation 631 and / or provide it to the user for verification. Further, the self-learning algorithm 625 is adapted to determine a new predefined process parameter 622 based on the comparison and automatically supply it to the data model unit 620 and / or provide it to the user for verification. Preferably, the self-learning algorithm 625 is adapted to use the verification result by the user as the basis for learning. According to an exemplary embodiment, the arithmetic unit 630 includes a self-learning algorithm 625 that sets an operation (control operation 631), which is either directly implemented in the system or provided to the operator for verification. Additionally, the operator's determination in verification can further form the basis for learning for the AI function. Further, based on the captured "actual" value 611, the AI can create and present new "target" values / ranges 621 obtained in the data model in either an automatic or operator-controlled manner, respectively.

[0120] In a specific embodiment, the following process parameters 611 are each monitored and measured (hereinafter, exemplary measurement methods are specified respectively) and captured in the database 610. i) Filling level; ultrasonic measurement, ii) Flow rate; flow meter, iii) H2O2 concentration; via redox potential, iv) Acid concentration; pH value (in-line) or titration (draw sample), v) Organic matter concentration; photometry (in-line) or cyclic voltammetry (draw sample), vi) Chloride concentration; titration (draw sample), vii) Iron / copper concentration; photometry or density measurement (in-line) or titration (draw sample), viii) Temperature; temperature sensor (in-line), ix) Pressure difference in membrane dialysis between the diffused matter and the dialysate; pressure sensor (in-line).

[0121] In this specific embodiment, after the arithmetic unit 630 compares (and evaluates, data-analyzes) the determined (measured) process parameter 611 and the predetermined process parameter 621, for example, the following control operations 631 (and respective operations) are determined and performed (and respectively triggered) by the arithmetic unit 630. i) Chlorine gas formation (e.g., via a gas sensor); control operation: electrolysis off, ii) Excessive peroxide load; control operation: no loading of the ion exchanger for treating the washing water, iii) Too low filling level; control operation: pump off, iv) Too high iron concentration in the electrolyte; control operation: switch on the ion exchange resin, v) Too high acid concentration in the electrolyte; control operation: switch on the membrane dialysis, or discharge of the electrolysis cell, vi) Low copper concentration in the electrolyte; control operation: discharge of the electrolysis cell and supply of the electrolyte to the pretreatment tank of the washing water, vii) Too high pressure difference in membrane dialysis; control operation: adaptation of the flow rate (flow velocity), viii) Copper concentration enrichment in the permeate of the ion exchanger for treating the washing water; control operation: regeneration, ix) Iron concentration enrichment in the permeate of the ion exchanger for removing iron from the plating wastewater; control operation: regeneration, x) Too high chloride concentration in the dialysate; control operation: adaptation of the flow rate (flow velocity).

Explanation of Signs

[0122] 1 First partial stream 2 Second partial stream 3 Third partial stream 4 Total stream 5 First separation stream 6 Second separation stream 7 Third separation stream 40 Metal salt-containing solvent, electrolyte 50 Metal element (copper) 52 Metal feedback to the etching process 54 Metal feedback to the plating process 60 Industrial plant for manufacturing printed circuit boards 100 Treatment of metal salt-containing (waste) solvent from the etching process in the manufacture of printed circuit boards 10 Metal salt-containing solvent, metal-concentrated electrolyte 11 Solvent to be treated 12 Solvent to be treated without acid 15 Acid 15a First part of the acid 15b Second part of the acid 110 First membrane dialysis 112 First membrane 113 First feed 115 First dialysate 116 First diffusate 120 Second membrane dialysis 122 Second membrane 123 Second feed 125 Second dialysate 126 Second diffusate, acidic diffusate 128 Acid concentration process 129 Concentrated acid, acid-concentrated diffusate 136 Metal-deficient acidic solvent (first separation stream) 140 Mixing / dilution reactor 145 Ion exchange process 150 Etching process 160 Hydrogen peroxide removal process 170 First process cycle 175 Additional acid, regenerated solvent, metal-deficient electrolyte 180 Second process cycle 185 Membrane filtration process, reverse osmosis process 185a Permeate 185b Concentrate 186a Salt concentrate 186b Metal-deficient salt concentrate 187 Base, sodium hydroxide 188 Purified water 189 Additional dilution process 190 Third process cycle 200 Treatment of metal salts and heterogeneous metal-containing solvents from the plating process in the manufacture of printed circuit boards 20 Metal salt-containing solvent 21 Iron and metal salt-containing solvent 231 Provision of (iron-concentrated acid) to the circuit board process 236 Acid-containing diffusate, second separation stream 250 Plating process 300 Treatment of metal salt-containing solvents from the washing water in the manufacture of printed circuit boards 30 Metal salt-containing washing water solvent 31 Solvent to be treated, total separation stream 32 Further washing water 350 Waste solvent, water with wastewater quality 352 Feed water 400 Recovery of metal elements from metal salt-containing solvents in the manufacture of printed circuit boards 405 Provision, combination, concentration 431 Provision of (iron-concentrated acid) to a further circuit board process 446 Diffusate with acid (third separation stream) 500 Further circuit board process, photoresist (iron chloride) process 600 Process control device 610 Database 611 Process parameters, actual values 620 Data model unit 621 Predetermined process parameters, target values 622 New predetermined process parameters 625 Self-learning algorithm 630 Arithmetic unit 631 Determined control actions

Claims

1. A method for treating an etching waste solvent from circuit board and / or substrate manufacturing, the method comprising: providing the etching waste solvent as a solvent to be treated, wherein the solvent to be treated contains a metal salt to be treated and an acid; as a result of treating the solvent to be treated in an ion exchange process, the metal salt to be treated is exchanged with a metal salt, and a metal salt-containing solvent is obtained from the solvent to be treated; whereby flowing a first process cycle through the ion exchange process, wherein the first process cycle is a first closed loop that produces substantially only metal elements; and flowing a second process cycle through the ion exchange process, wherein the second process cycle is a second closed loop that produces substantially only purified water and / or a metal-deficient salt concentrate, comprising, the ion exchange process having a step of applying an ion exchanger having an ion exchange resin, the salt in the metal salt and the salt in the metal salt to be treated are different salts, and the salts have at least two of the group consisting of chloride, sulfate, nitrate, and phosphate, method.

2. the metal in the metal salt and the metal in the metal salt to be treated are the same metal, and the metal is at least one of the group consisting of copper, nickel, cobalt, tin, cadmium, magnesium, sodium, silver, and gold The method according to claim 1.

3. The first process cycle further comprises: flowing a further acid different from the acid through the ion exchange process, as a result, the further acid removes the metal from the ion exchange process to provide the metal salt-containing solvent; transporting the metal salt-containing solvent to a metal element recovery process, and obtaining the metal element and the further acid from the metal salt-containing solvent; and feeding back the further acid to the ion exchange process The method according to claim 1 or 2, having.

4. The metal element recovery process comprises an electrolysis process, the metal salt-containing solvent is similar to a metal-concentrated electrolyte entering the electrolysis process, and the further acid is similar to a metal-deficient electrolyte exiting the electrolysis process, The method according to claim 3.

5. The second process cycle further comprises: Flowing the solvent to be treated through the ion exchange process, where the solvent to be treated is separated into a metal remaining in the ion exchange process after separation and a metal-deficient acidic solvent; Treating the metal-deficient acidic solvent in a water treatment process to obtain the purified water; and Feeding back the purified water to the ion exchange process and / or Feeding back the purified water to a further circuit board and / or substrate manufacturing process and / or Discharging the purified water as water meeting the discharge water quality The method according to any one of claims 1 to 4, comprising:

6. The water treatment process includes a membrane filtration process, The permeate includes the purified water, and The concentrate includes a salt concentrate, The method according to claim 5.

7. The second process cycle further includes: Feeding back the salt concentrate to the ion exchange process, where the metal of the salt concentrate remains in the ion exchange process; and thereby Providing the metal-deficient salt concentrate The method according to claim 6, comprising:

8. The metal-deficient salt concentrate substantially does not contain heavy metals, The method according to claim 7.

9. The method further includes: Adding a base to the metal-deficient acidic solvent, where the base and the acid of the metal-deficient acidic solvent form a salt of the salt concentrate, The method according to any one of claims 5 to 8, comprising:

10. Diluting the solvent to be treated before the ion exchange process The method according to any one of claims 1 to 9, further comprising:

11. The step of providing the solvent to be treated is integrated within a third process cycle that is a third closed loop and substantially produces no waste, The method according to any one of claims 1 to 10.

12. The third process cycle includes: Removing the acid from the solvent to be treated by membrane dialysis to provide an acid-free solvent to be treated and an acidic diffusate The method according to claim 11, comprising:

13. The third process cycle includes: Further concentrating the acidic diffusate in an acid concentration process to obtain an acid-concentrated diffusate; and Feeding back the acidic diffusate and / or the acid-concentrated diffusate to an etching process providing the etching waste solvent to generate the solvent to be treated The method according to claim 12, further comprising

14. The step of providing the solvent to be treated is: Hydrogen peroxide (H ２ O ２ ) removal process is performed The method according to any one of claims 1 to 13, comprising

15. An etching process module that generates an etching waste solvent as the solvent to be treated, wherein the solvent to be treated has a metal salt to be treated and an acid; An ion exchange process module configured such that as a result of treating the solvent to be treated, the metal salt to be treated is exchanged with a metal salt, and a metal salt-containing solvent is obtained from the solvent to be treated; A first process cycle flowing through the ion exchange process module, wherein the first process cycle is a first closed loop that produces substantially only metal elements; and A second process cycle flowing through the ion exchange process module, wherein the second process cycle is a second closed loop that produces substantially only purified water and / or a metal-deficient salt concentrate, comprising The ion exchange process module has an ion exchanger having an ion exchange resin, The salts in the metal salt and the salts in the metal salt to be treated are different salts, and the salts have at least two of the group consisting of chlorides, sulfates, nitrates, and phosphates, A circuit board and / or a substrate manufacturing industrial plant.

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