CN114806581B - Method for recycling binary waste acid - Google Patents
Method for recycling binary waste acid Download PDFInfo
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- CN114806581B CN114806581B CN202210429595.7A CN202210429595A CN114806581B CN 114806581 B CN114806581 B CN 114806581B CN 202210429595 A CN202210429595 A CN 202210429595A CN 114806581 B CN114806581 B CN 114806581B
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K13/00—Etching, surface-brightening or pickling compositions
- C09K13/04—Etching, surface-brightening or pickling compositions containing an inorganic acid
- C09K13/08—Etching, surface-brightening or pickling compositions containing an inorganic acid containing a fluorine compound
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F7/00—Compounds of aluminium
- C01F7/48—Halides, with or without other cations besides aluminium
- C01F7/50—Fluorides
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Abstract
The application relates to a recycling method of binary waste acid, which comprises the following steps: (1) Adding acid liquor into the binary waste acid for treatment, and then carrying out solid-liquid separation to obtain aluminum fluoride precipitate and primary purifying liquid; (2) Distilling the primary purified liquid obtained in the step (1) to obtain a secondary purified liquid and the acid liquid; (3) And (3) carrying out nanofiltration treatment on the secondary purifying liquid obtained in the step (2) to obtain dibasic acid liquid and phosphoric-sulfuric dibasic acid etching liquid. The recycling method provided by the application realizes the recycling of the binary waste acid generated in the aluminum etching by adopting a specific treatment process.
Description
Technical Field
The application relates to the field of secondary utilization of resources, in particular to a recycling method of binary waste acid.
Background
Currently, in the field of electronic device manufacturing, etching treatment is generally required to be performed on the used aluminum material to ensure the performance of the product.
As disclosed in CN106148960a, in the method for etching aluminum, by adjusting the temperature and pressure conditions in the etching chamber in the dry etching process, the aluminum chloride is kept in a gaseous state, so as to reduce the generation of aluminum chloride particles, and the residual amount of aluminum chloride in the etching chamber after air extraction is small, thereby reducing the content of aluminum-containing compounds in the etching chamber and reducing the generation of aluminum-containing particles; or the content of aluminum-containing compounds in the etching cavity is reduced by adding a gas flushing step before a fluorine-chlorine replacement process after the dry etching process, so that the generation of aluminum-containing particles is reduced; or the cleaning step of the etching cavity is added before the dry etching process, so that the content of aluminum-containing compounds in the etching cavity is reduced, the generation of aluminum-containing particles in the etching cavity is reduced, the content of aluminum-containing particles in the etching cavity can be reduced by the three methods, the probability that the particles fall on a film layer to be etched in the dry etching process is reduced, the problems of circuit etching residues and short circuits are solved, and the product yield is improved.
CN102206821a discloses an aluminum alloy etching and adjusting composition, which is divided into two components a and B, wherein component a is etching solution, and component B is adjusting solution; the component A comprises ferric trichloride, phosphoric acid, a pH regulator, a corrosion inhibitor and a defoaming agent; the component B comprises phosphoric acid and sulfuric acid, and also provides an aluminum alloy etching method, wherein an aluminum alloy substrate is placed in etching liquid for etching at 20-40 ℃, and then the aluminum alloy is placed in adjusting liquid at 60-80 ℃ for adjustment. The two-step acid etching system well solves the defects that a large amount of black ash generated by etching liquid is not easy to remove, the surface is rough, burrs exist on the edge and side etching is serious.
In general, an acid-containing waste etching solution is formed in the etching process, and a waste solution for etching materials contains a large amount of aluminum ions, so that it is difficult to realize green recovery.
Disclosure of Invention
In view of the problems existing in the prior art, the application aims to provide a recycling method of binary waste acid, so as to solve the problem that the binary waste acid generated in the etching process cannot be effectively utilized.
To achieve the purpose, the application adopts the following technical scheme:
the application provides a recycling method of binary waste acid, which comprises the following steps:
(1) Adding acid liquor into the binary waste acid for treatment, and then carrying out solid-liquid separation to obtain aluminum fluoride precipitate and primary purifying liquid;
(2) Distilling the primary purified liquid obtained in the step (1) to obtain a secondary purified liquid and the acid liquid;
(3) And (3) carrying out nanofiltration treatment on the secondary purifying liquid obtained in the step (2) to obtain dibasic acid liquid and phosphoric-sulfuric dibasic acid etching liquid.
The recycling method provided by the application realizes recycling of the binary waste acid generated in aluminum etching by adopting a specific treatment process, and has the advantages of simple process, low operation cost, high waste acid recycling rate, byproduct aluminum fluoride product and the like.
In the application, the acid liquor obtained in the step (2) can be returned to the step (1) for further treatment.
In the application, concentrated water generated by nanofiltration treatment is returned to be used as binary waste acid for cyclic iterative treatment.
As a preferred technical solution of the present application, the acid solution includes a hydrofluoric acid solution.
In a preferred embodiment of the present application, the hydrofluoric acid solution may have a mass concentration of 1 to 10%, for example, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5% or 10%, etc., but the present application is not limited to the above-mentioned values, and other values not mentioned in the above range are equally applicable.
In a preferred embodiment of the present application, the distillation temperature is 90 to 120℃and may be, for example, 90℃92℃94℃96℃98℃100℃102℃104℃106℃108℃110℃112℃114℃116℃118℃120℃or 120℃and the like, but the present application is not limited to the values listed and other values not listed in the range are equally applicable.
In a preferred embodiment of the present application, the pressure of the distillation is 20 to 30kPa, for example, 20kPa, 20.5kPa, 21kPa, 21.5kPa, 22kPa, 22.5kPa, 23kPa, 23.5kPa, 24kPa, 24.5kPa, 25kPa, 25.5kPa, 26kPa, 26.5kPa, 27kPa, 27.5kPa, 28kPa, 28.5kPa, 29kPa, 29.5kPa or 30kPa, etc., but the pressure is not limited to the values listed, and other values not listed in the range are equally applicable.
As a preferred embodiment of the present application, the Zeta potential of the filter membrane used in the nanofiltration treatment is-80 mV to-70 mV, for example, -80mV, -79.5mV, -79mV, -78.5mV, -78mV, -77.5mV, -77, -76.5mV, -76mV, -75.5mV, -74.5mV, -74mV, -73.5mV, -73mV, -72.5mV, -72mV, -71.5mV, -70.5mV or-70 mV, etc., but not limited to the values listed, other non-listed values within this range are equally applicable.
In a preferred embodiment of the present application, the pore size of the filter is 8 to 10nm, for example, 8nm, 8.1nm, 8.2nm, 8.3nm, 8.4nm, 8.5nm, 8.6nm, 8.7nm, 8.8nm, 8.9nm, 9nm, 9.1nm, 9.2nm, 9.3nm, 9.4nm, 9.5nm, 9.6nm, 9.7nm, 9.8nm, 9.9nm or 10nm, etc., but the pore size is not limited to the values listed, and other non-listed values within the range are equally applicable.
As a preferred embodiment of the present application, the pressure in the nanofiltration is 80-100bar, for example 80bar, 81bar, 82bar, 83bar, 84bar, 85bar, 86bar, 87bar, 88bar, 89bar, 90bar, 91bar, 92bar, 93bar, 94bar, 95bar, 96bar, 97bar, 98bar, 99bar or 100bar, etc., but not limited to the recited values, other non-recited values within this range are equally applicable.
As a preferable technical scheme of the application, the membrane flux in the nanofiltration is 6-7L/(m) 2 H), for example, may be 6L/(m) 2 ·h)、6.1L/(m 2 ·h)、6.2L/(m 2 ·h)、6.3L/(m 2 ·h)、6.4L/(m 2 ·h)、6.5L/(m 2 ·h)、6.6L/(m 2 ·h)、6.7L/(m 2 ·h)、6.8L/(m 2 ·h)、6.9L/(m 2 H) or 7L/(m) 2 H), etc., but are not limited to the recited values, and other values not recited in this range are equally applicable.
As a preferable technical scheme of the application, the recycling method comprises the following steps:
(1) Adding acid liquor into the binary waste acid for treatment, and then carrying out solid-liquid separation to obtain aluminum fluoride precipitate and primary purifying liquid; the acid solution comprises hydrofluoric acid solution; the mass concentration of the hydrofluoric acid solution is 1-10%;
(2) Performing first distillation on the primary purified liquid obtained in the step (1) to obtain secondary purified liquid and the acid liquid; the distillation temperature is 90-120 ℃; the pressure of the distillation is 20-30kPa;
(3) Carrying out nanofiltration treatment on the secondary purifying liquid obtained in the step (2) to obtain dibasic acid liquid and phosphoric-sulfuric dibasic acid etching liquid; the Zeta potential of the filter membrane used in the nanofiltration treatment is-80 mV to-70 mV; the aperture of the filter membrane is 8-10nm; the pressure in the nanofiltration is 80-100bar; the membrane flux in the nanofiltration is 6-7L/(m) 2 ·h)。
Compared with the prior art, the application has at least the following beneficial effects:
(1) Through tests, the regenerated dibasic acid obtained by the process meets the use requirement, and the recycling is realized.
(2) The higher operating cost of external co-processing of the original binary mixed acid is reduced.
(3) The recovery rate of regenerated acid is high, the utilization rate of the conventional scheme is 70%, and the recovery rate of the method can reach more than 90%.
Drawings
Fig. 1 is a schematic diagram of a recycling method according to embodiment 1 of the present application.
The present application will be described in further detail below. The following examples are merely illustrative of the present application and are not intended to represent or limit the scope of the application as defined in the claims.
Detailed Description
For a better illustration of the present application, which is convenient for understanding the technical solution of the present application, exemplary but non-limiting examples of the present application are as follows:
example 1
The embodiment provides a recycling method of binary waste acid, as shown in fig. 1, comprising the following steps:
(1) Adding acid liquor into the binary waste acid for treatment, and then carrying out solid-liquid separation to obtain aluminum fluoride precipitate and primary purifying liquid; the acid solution comprises hydrofluoric acid solution; the mass concentration of the hydrofluoric acid solution is 6%;
(2) Performing first distillation on the primary purified liquid obtained in the step (1) to obtain secondary purified liquid and the acid liquid; the temperature of the distillation is 108 ℃; the pressure of the distillation is 25kPa;
(3) Carrying out nanofiltration treatment on the secondary purifying liquid obtained in the step (2) to obtain dibasic acid liquid and phosphoric-sulfuric dibasic acid etching liquid; the Zeta potential of the filter membrane used in the nanofiltration treatment is-75 mV; the pore diameter of the filter membrane is 9nm; the pressure in the nanofiltration was 90bar; the membrane flux in the nanofiltration was 6.5L/(m) 2 ·h)。
The compositions of the binary waste acid used in this example were: 20% sulfuric acid, 35% phosphoric acid, 40% water, 2.5% aluminum;
the purity and recovery of the obtained product are shown in Table 1.
Example 2
The embodiment provides a recycling method of binary waste acid, which comprises the following steps:
(1) Adding acid liquor into the binary waste acid for treatment, and then carrying out solid-liquid separation to obtain aluminum fluoride precipitate and primary purifying liquid; the acid solution comprises hydrofluoric acid solution; the mass concentration of the hydrofluoric acid solution is 1%;
(2) Performing first distillation on the primary purified liquid obtained in the step (1) to obtain secondary purified liquid and the acid liquid; the temperature of the distillation is 90 ℃; the pressure of the distillation is 20kPa;
(3) Carrying out nanofiltration treatment on the secondary purifying liquid obtained in the step (2) to obtain dibasic acid liquid and phosphoric-sulfuric dibasic acid etching liquid; the Zeta potential of the filter membrane used in the nanofiltration treatment is-80 mVmV; the pore diameter of the filter membrane is 10nm; the pressure in the nanofiltration was 100bar; the membrane flux in the nanofiltration is 6L/(m) 2 ·h)。
The compositions of the binary waste acid used in this example were: 20% sulfuric acid, 35% phosphoric acid, 40% water, 4% aluminum;
the purity and recovery of the obtained product are shown in Table 1.
Example 3
The embodiment provides a recycling method of binary waste acid, which comprises the following steps:
(1) Adding acid liquor into the binary waste acid for treatment, and then carrying out solid-liquid separation to obtain aluminum fluoride precipitate and primary purifying liquid; the acid solution comprises hydrofluoric acid solution; the mass concentration of the hydrofluoric acid solution is 10%;
(2) Performing first distillation on the primary purified liquid obtained in the step (1) to obtain secondary purified liquid and the acid liquid; the temperature of the distillation is 120 ℃; the pressure of the distillation is 30kPa;
(3) Carrying out nanofiltration treatment on the secondary purifying liquid obtained in the step (2) to obtain dibasic acid liquid and phosphoric-sulfuric dibasic acid etching liquid; the Zeta potential of the filter membrane used in the nanofiltration treatment is-70 mV; the aperture of the filter membrane is 8nm; the pressure in the nanofiltration was 80bar; the membrane flux in the nanofiltration is 7L/(m) 2 ·h)。
The compositions of the binary waste acid used in this example were: 15% sulfuric acid, 35% phosphoric acid, 45% water, 4% aluminum;
the purity and recovery of the obtained product are shown in Table 1.
Comparative example 1
The only difference from example 1 is that the membrane used in the nanofiltration treatment has a Zeta potential of-100 mV. The purity and recovery of the obtained product are shown in Table 1.
Comparative example 2
The only difference from example 1 is that the membrane used in the nanofiltration treatment has a Zeta potential of-50 mV.
The purity and recovery of the obtained product are shown in Table 1.
Comparative example 3
The only difference from example 1 is that the membrane used in the nanofiltration treatment has a Zeta potential of 20mV.
The purity and recovery of the obtained product are shown in Table 1.
TABLE 1
| Recovery rate of dibasic acid | Purity of aluminum fluoride | |
| Example 1 | 95％ | 98％ |
| Example 2 | 98％ | 99％ |
| Example 3 | 92％ | 99％ |
| Comparative example 1 | 70％ | 98％ |
| Comparative example 2 | 65％ | 98％ |
| Comparative example 3 | 50％ | 98％ |
As is clear from the results of the above examples and comparative examples, the Zeta potential of the filter membrane needs to be strictly controlled in the present application to ensure efficient recovery of dibasic acid.
It is stated that the detailed structural features of the present application are described by the above embodiments, but the present application is not limited to the above detailed structural features, i.e., it does not mean that the present application must be implemented depending on the above detailed structural features. It should be apparent to those skilled in the art that any modifications of the present application, equivalent substitutions of selected components of the present application, addition of auxiliary components, selection of specific modes, etc., are within the scope of the present application and the scope of the disclosure.
The preferred embodiments of the present application have been described in detail above, but the present application is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present application within the scope of the technical concept of the present application, and all the simple modifications belong to the protection scope of the present application.
In addition, the specific features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various possible combinations are not described further.
Moreover, any combination of the various embodiments of the application can be made without departing from the spirit of the application, which should also be considered as disclosed herein.
Claims (7)
1. The recycling method of the binary waste acid is characterized by comprising the following steps of:
(1) Adding acid liquor into the binary waste acid for treatment, and then carrying out solid-liquid separation to obtain aluminum fluoride precipitate and primary purifying liquid; the acid solution comprises hydrofluoric acid solution; the mass concentration of the hydrofluoric acid solution is 1-10%;
(2) Distilling the primary purified liquid obtained in the step (1) to obtain a secondary purified liquid and the acid liquid;
(3) Carrying out nanofiltration treatment on the secondary purifying liquid obtained in the step (2) to obtain dibasic acid liquid and phosphoric-sulfuric dibasic acid etching liquid; the Zeta potential of the filter membrane used in the nanofiltration treatment is-80 mV to-70 mV;
the recovery rate of the dibasic acid reaches more than 90 percent.
2. The recycling method according to claim 1, wherein the temperature of the distillation is 90 to 120 ℃.
3. The recycling method according to claim 1, wherein the pressure of the distillation is 20 to 30kPa.
4. The recycling method according to claim 1, wherein the pore size of the filter membrane is 8-10nm.
5. The recycling method according to claim 1, wherein the pressure in the nanofiltration is 80-100bar.
6. The recycling method according to claim 1, wherein the membrane flux in the nanofiltration is 6-7L/(m) 2 ·h)。
7. The recycling method according to claim 1, characterized in that the recycling method comprises the steps of:
(1) Adding acid liquor into the binary waste acid for treatment, and then carrying out solid-liquid separation to obtain aluminum fluoride precipitate and primary purifying liquid; the acid solution comprises hydrofluoric acid solution; the mass concentration of the hydrofluoric acid solution is 1-10%;
(2) Distilling the primary purified liquid obtained in the step (1) to obtain a secondary purified liquid and the acid liquid; the distillation temperature is 90-120 ℃; the pressure of the distillation is 20-30kPa;
(3) Carrying out nanofiltration treatment on the secondary purifying liquid obtained in the step (2) to obtain dibasic acid liquid and phosphoric-sulfuric dibasic acid etching liquid; the Zeta potential of the filter membrane used in the nanofiltration treatment is-80 mV to-70 mV; the aperture of the filter membrane is 8-10nm; the pressure in the nanofiltration is 80-100bar; the membrane flux in the nanofiltration is 6-7L/(m) 2 ·h)。
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5723097A (en) * | 1995-12-08 | 1998-03-03 | Goldendale Aluminum Company | Method of treating spent potliner material from aluminum reduction cells |
| CN101215099A (en) * | 2008-01-16 | 2008-07-09 | 京东方科技集团股份有限公司 | Flat glass substrate attenuation etching liquid |
| CN101654273A (en) * | 2008-08-20 | 2010-02-24 | 湖北富驰化工医药股份有限公司 | Production process for preparing aluminium fluoride by using ammonium bicarbonate |
| CN113718107A (en) * | 2021-09-02 | 2021-11-30 | 中南大学 | Method for efficiently extracting lithium from lithium-rich aluminum electrolyte waste residue and preparing anhydrous aluminum fluoride |
| CN114230076A (en) * | 2021-12-20 | 2022-03-25 | 廖崇亨 | Metal surface treatment liquid recycling system and operation method thereof |
| CN114262089A (en) * | 2021-12-23 | 2022-04-01 | 天津市海跃水处理高科技有限公司 | Method for recycling and treating aluminum anodic oxidation wastewater containing phosphoric acid and sulfuric acid |
-
2022
- 2022-04-22 CN CN202210429595.7A patent/CN114806581B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5723097A (en) * | 1995-12-08 | 1998-03-03 | Goldendale Aluminum Company | Method of treating spent potliner material from aluminum reduction cells |
| CN101215099A (en) * | 2008-01-16 | 2008-07-09 | 京东方科技集团股份有限公司 | Flat glass substrate attenuation etching liquid |
| CN101654273A (en) * | 2008-08-20 | 2010-02-24 | 湖北富驰化工医药股份有限公司 | Production process for preparing aluminium fluoride by using ammonium bicarbonate |
| CN113718107A (en) * | 2021-09-02 | 2021-11-30 | 中南大学 | Method for efficiently extracting lithium from lithium-rich aluminum electrolyte waste residue and preparing anhydrous aluminum fluoride |
| CN114230076A (en) * | 2021-12-20 | 2022-03-25 | 廖崇亨 | Metal surface treatment liquid recycling system and operation method thereof |
| CN114262089A (en) * | 2021-12-23 | 2022-04-01 | 天津市海跃水处理高科技有限公司 | Method for recycling and treating aluminum anodic oxidation wastewater containing phosphoric acid and sulfuric acid |
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