CN113774387A - Smokeless and odorless bleaching agent for die-casting aluminum and preparation method and application thereof - Google Patents
Smokeless and odorless bleaching agent for die-casting aluminum and preparation method and application thereof Download PDFInfo
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- CN113774387A CN113774387A CN202111110047.XA CN202111110047A CN113774387A CN 113774387 A CN113774387 A CN 113774387A CN 202111110047 A CN202111110047 A CN 202111110047A CN 113774387 A CN113774387 A CN 113774387A
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- raw material
- die
- smokeless
- odorless
- bleaching agent
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- 239000007844 bleaching agent Substances 0.000 title claims abstract description 29
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title claims abstract description 26
- 229910052782 aluminium Inorganic materials 0.000 title claims abstract description 26
- 238000004512 die casting Methods 0.000 title claims abstract description 18
- 230000009965 odorless effect Effects 0.000 title claims abstract description 17
- 238000002360 preparation method Methods 0.000 title claims abstract description 13
- 239000002994 raw material Substances 0.000 claims abstract description 46
- NROKBHXJSPEDAR-UHFFFAOYSA-M potassium fluoride Chemical compound [F-].[K+] NROKBHXJSPEDAR-UHFFFAOYSA-M 0.000 claims abstract description 19
- 238000006243 chemical reaction Methods 0.000 claims abstract description 18
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims abstract description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 14
- 238000000034 method Methods 0.000 claims abstract description 13
- MIMUSZHMZBJBPO-UHFFFAOYSA-N 6-methoxy-8-nitroquinoline Chemical compound N1=CC=CC2=CC(OC)=CC([N+]([O-])=O)=C21 MIMUSZHMZBJBPO-UHFFFAOYSA-N 0.000 claims abstract description 11
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000011698 potassium fluoride Substances 0.000 claims abstract description 9
- 235000003270 potassium fluoride Nutrition 0.000 claims abstract description 9
- 238000003756 stirring Methods 0.000 claims abstract description 9
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 claims abstract description 7
- 235000019345 sodium thiosulphate Nutrition 0.000 claims abstract description 7
- 239000000203 mixture Substances 0.000 claims abstract description 5
- BAERPNBPLZWCES-UHFFFAOYSA-N (2-hydroxy-1-phosphonoethyl)phosphonic acid Chemical compound OCC(P(O)(O)=O)P(O)(O)=O BAERPNBPLZWCES-UHFFFAOYSA-N 0.000 claims abstract description 3
- 239000000463 material Substances 0.000 claims description 5
- 238000005406 washing Methods 0.000 claims description 2
- 238000004061 bleaching Methods 0.000 abstract description 5
- 230000007797 corrosion Effects 0.000 abstract description 2
- 238000005260 corrosion Methods 0.000 abstract description 2
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 12
- 230000000052 comparative effect Effects 0.000 description 8
- AEMRFAOFKBGASW-UHFFFAOYSA-N Glycolic acid Chemical compound OCC(O)=O AEMRFAOFKBGASW-UHFFFAOYSA-N 0.000 description 4
- 238000011049 filling Methods 0.000 description 4
- BJEPYKJPYRNKOW-REOHCLBHSA-N (S)-malic acid Chemical compound OC(=O)[C@@H](O)CC(O)=O BJEPYKJPYRNKOW-REOHCLBHSA-N 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- BJEPYKJPYRNKOW-UHFFFAOYSA-N alpha-hydroxysuccinic acid Natural products OC(=O)C(O)CC(O)=O BJEPYKJPYRNKOW-UHFFFAOYSA-N 0.000 description 2
- XLYOFNOQVPJJNP-ZSJDYOACSA-N heavy water Substances [2H]O[2H] XLYOFNOQVPJJNP-ZSJDYOACSA-N 0.000 description 2
- 239000001630 malic acid Substances 0.000 description 2
- 235000011090 malic acid Nutrition 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- LNOPIUAQISRISI-UHFFFAOYSA-N n'-hydroxy-2-propan-2-ylsulfonylethanimidamide Chemical compound CC(C)S(=O)(=O)CC(N)=NO LNOPIUAQISRISI-UHFFFAOYSA-N 0.000 description 2
- LJCNRYVRMXRIQR-OLXYHTOASA-L potassium sodium L-tartrate Chemical compound [Na+].[K+].[O-]C(=O)[C@H](O)[C@@H](O)C([O-])=O LJCNRYVRMXRIQR-OLXYHTOASA-L 0.000 description 2
- 229940074439 potassium sodium tartrate Drugs 0.000 description 2
- 229910001388 sodium aluminate Inorganic materials 0.000 description 2
- 235000011006 sodium potassium tartrate Nutrition 0.000 description 2
- 229910052911 sodium silicate Inorganic materials 0.000 description 2
- DMOXNIKYXJYCFQ-UHFFFAOYSA-N (2-hydroxy-1-phosphonooxyethyl) dihydrogen phosphate Chemical compound OP(=O)(O)OC(CO)OP(O)(O)=O DMOXNIKYXJYCFQ-UHFFFAOYSA-N 0.000 description 1
- 241000565357 Fraxinus nigra Species 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- DDAQLPYLBPPPRV-UHFFFAOYSA-N [4-(hydroxymethyl)-2-oxo-1,3,2lambda5-dioxaphosphetan-2-yl] dihydrogen phosphate Chemical compound OCC1OP(=O)(OP(O)(O)=O)O1 DDAQLPYLBPPPRV-UHFFFAOYSA-N 0.000 description 1
- 229910021502 aluminium hydroxide Inorganic materials 0.000 description 1
- WNROFYMDJYEPJX-UHFFFAOYSA-K aluminium hydroxide Chemical compound [OH-].[OH-].[OH-].[Al+3] WNROFYMDJYEPJX-UHFFFAOYSA-K 0.000 description 1
- 239000010407 anodic oxide Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 229910001679 gibbsite Inorganic materials 0.000 description 1
- 230000005802 health problem Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000000779 smoke Substances 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 235000019795 sodium metasilicate Nutrition 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/12—Light metals
- C23G1/125—Light metals aluminium
Abstract
The invention discloses a preparation method of a smokeless and odorless bleaching agent for die-casting aluminum, which comprises the following steps of: adding a certain amount of pure water into a reaction kettle; sequentially adding the first raw material, the second raw material, the third raw material and the fourth raw material into the reaction kettle, and stirring while adding; the first raw material is hydroxyethylidene diphosphonic acid or citric acid, the second raw material is potassium fluoride, the third raw material is ammonium bifluoride, and the fourth raw material is sodium thiosulfate or hydrogen peroxide; the mixture was stirred well until completely dissolved. The invention also discloses a smokeless and odorless bleaching agent for die-casting aluminum and an application thereof. The bleaching agent prepared by the method has strong bleaching capability on die-cast aluminum, is weak in corrosion on the die-cast aluminum, is smokeless and odorless, reduces the harm to a human body in the process of producing electronic products, reduces the pollution to the environment, and meets the requirements of market and industry development.
Description
Technical Field
The invention relates to the technical field of bleaching agents, in particular to a smokeless and odorless bleaching agent for die-casting aluminum and a preparation method and application thereof.
Background
With the rapid development of the electronic industry and people-oriented development concept in this year, the surface treatment and maintenance of electronic components are related to not only the production cost, but also the environmental protection and the health problems of operation and users. At present, most of die-cast aluminum bleaching agent products are strong in acidity, and can emit yellow smoke and release NO and NO in the using process2And the like, and in addition, the phenomena of air blowing and the like exist in the process of storage and transportation. Meanwhile, the product has pungent smell in production and use, and can injure the health of operators and usersKang, also causes serious pollution to the environment. Therefore, how to reduce the harm to human body and the pollution to environment in the process of producing electronic products becomes the trend of industry development and the market development demand.
Disclosure of Invention
One object of the present invention is: provides a smokeless and odorless bleaching agent for die-casting aluminum, a preparation method and application thereof, which are used for solving the problems in the prior art.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of a smokeless and odorless bleaching agent for die-casting aluminum comprises the following steps:
adding a certain amount of pure water into a reaction kettle;
sequentially adding the first raw material, the second raw material, the third raw material and the fourth raw material into the reaction kettle, and stirring while adding;
the first raw material is hydroxyethylidene diphosphonic acid (C2H 8O7P 2) or citric acid (C6H 8O 7), the second raw material is potassium fluoride (KF), the third raw material is ammonium bifluoride (NH 4 HF), and the fourth raw material is sodium thiosulfate (Na 2S2O 3) or hydrogen peroxide (H2O 2);
the mixture was stirred well until completely dissolved.
As a preferable technical scheme, the parts of the first raw material are 6-10, the parts of the second raw material are 15-25, the parts of the third raw material are 5-10, the parts of the fourth raw material are 5-15, and the parts of the pure water are 55-60.
As a preferable embodiment, the stirring time of the first raw material is 30 minutes.
As a preferable embodiment, the stirring time of the second raw material is 30 minutes.
As a preferable embodiment, the stirring time of the third raw material is 30 minutes.
As a preferable embodiment, the stirring time of the fourth raw material is 30 minutes.
As a preferred technical scheme, the time for fully stirring the mixture is 2 hours.
A smokeless and odorless bleaching agent for die-casting aluminum, which is obtained by adopting the preparation method of any one of the above.
The application of the smokeless and odorless bleaching agent for die casting aluminum is characterized in that the die casting aluminum after alkali washing is bleached by adopting the smokeless and odorless bleaching agent for die casting aluminum.
The invention has the beneficial effects that: the bleaching agent has strong bleaching capacity on die-cast aluminum, is weak in corrosion on the die-cast aluminum, is smokeless and odorless, reduces harm to a human body in the process of producing electronic products, reduces pollution to the environment, and meets the requirements of market and industry development.
Detailed Description
The technical scheme of the invention is further illustrated by the following specific examples and comparative examples.
The first embodiment is as follows:
in this example, the bleaching agent comprises the following raw materials in percentage by weight:
8% of citric acid;
20% of potassium fluoride;
6% of ammonium bifluoride;
6 percent of sodium thiosulfate;
60% of pure water;
the raw materials are added according to the weight percentage and stirred for preparation, pure water is firstly added into a reaction kettle, then citric acid is added and stirred for 30 minutes, then potassium fluoride is added and stirred for 30 minutes, then ammonium bifluoride is added and stirred for 30 minutes, finally sodium thiosulfate is added and stirred for 30 minutes until the raw materials are completely dissolved, and a valve of the reaction kettle is opened for filling.
The bleaching agent is applied to the bleaching agent after alkaline anodic oxide film stripping of die-cast aluminum and aluminum alloy binders, and has good effect.
Example two:
in this example, the bleaching agent comprises the following raw materials in percentage by weight:
6% of hydroxyethylidene diphosphate;
22% of potassium fluoride;
9% of ammonium bifluoride;
8% of hydrogen peroxide;
55% of pure water;
the raw materials are added according to the weight percentage and stirred for preparation, pure water is firstly added into a reaction kettle, then hydroxyl ethylidene diphosphoric acid is added and stirred for 30 minutes, then potassium fluoride is added and stirred for 30 minutes, then ammonium bifluoride is added and stirred for 30 minutes, finally hydrogen peroxide is added and stirred for 30 minutes until the potassium fluoride is completely dissolved, and a valve of the reaction kettle is opened for filling.
Comparative example one:
in the comparative example, the bleaching agent comprises the following raw materials in percentage by weight:
8% of glycolic acid;
20% of potassium fluoride;
6% of ammonium bifluoride;
6 percent of sodium thiosulfate;
60% of pure water;
the raw materials are added according to the weight percentage and stirred for preparation, pure water is firstly added into a reaction kettle, then glycolic acid is added and stirred for 30 minutes, then potassium fluoride is added and stirred for 30 minutes, then ammonium bifluoride is added and stirred for 30 minutes, finally sodium thiosulfate is added and stirred for 30 minutes until the raw materials are completely dissolved, and a valve of the reaction kettle is opened for filling.
Comparative example two:
in the comparative example, the bleaching agent comprises the following raw materials in percentage by weight:
6% of sulfamic acid;
malic acid 22%;
9% of ammonium bifluoride;
8% of potassium sodium tartrate;
55% of pure water;
the raw materials are added according to the weight percentage and stirred for preparation, pure water is firstly added into a reaction kettle, then sulfamic acid is added and stirred for 30 minutes, then malic acid is added and stirred for 30 minutes, then ammonium bifluoride is added and stirred for 30 minutes, finally potassium sodium tartrate is added and stirred for 30 minutes until the materials are completely dissolved, and a valve of the reaction kettle is opened for filling.
And (3) blending the bleaching agents prepared in the first and second examples and the bleaching agents prepared in the first and second comparative examples according to the following proportion:
bleaching agent: 95 percent
Concentrated nitric acid: 5 percent of
The middle frame of the cell phone with the die-casting aluminum and aluminum alloy combination piece to be bleached is respectively placed in the tank liquid prepared in the first and second examples and the first and second comparative examples for soaking and bleaching at 30 ℃, the cleaning time is 3 minutes, the bleaching degree, the corrosivity and the treatment amount of the combination piece per kilogram of the bleaching agent prepared in the first and second examples and the first and second comparative examples are compared and tested, and the test results are shown in the table:
the main components of the black ash generated after the die-casting aluminum alkaline etching are as follows: al (OH)3、NaAlO2、Na2SiO3
1. The aluminum reacts with water firstly, and the reaction formula is as follows: 2Al +6H2O=2Al(OH)3+3H2
2. Formed Al (OH)3Reacting with alkali (NaOH), wherein the reaction formula is as follows: al (OH)3+NaOH=NaAlO2+2H2O
3. The chemical equation for the reaction of silicon with sodium hydroxide solution is: si +2NaOH + H2O = Na2SiO3+2H2 ═ c
The main chemical reactions in the bleaching process:
1、H++NaOH=Na++2H2O
2、3H++Al(OH)3=Al3++3H2O
it should be noted that the above-mentioned embodiments are only preferred embodiments of the present invention and the technical principles used, and any changes or substitutions which can be easily conceived by those skilled in the art within the technical scope of the present invention disclosed herein should be covered within the protective scope of the present invention.
Claims (9)
1. A preparation method of a smokeless and odorless bleaching agent for die-casting aluminum is characterized by comprising the following steps of:
adding a certain amount of pure water into a reaction kettle;
sequentially adding the first raw material, the second raw material, the third raw material and the fourth raw material into the reaction kettle, and stirring while adding;
the first raw material is hydroxyethylidene diphosphonic acid or citric acid, the second raw material is potassium fluoride, the third raw material is ammonium bifluoride, and the fourth raw material is sodium thiosulfate or hydrogen peroxide;
the mixture was stirred well until completely dissolved.
2. The method for preparing the smokeless and odorless bleaching agent for die-casting aluminum according to claim 1, wherein the parts of the first raw material are 6 to 10, the parts of the second raw material are 15 to 25, the parts of the third raw material are 5 to 10, the parts of the fourth raw material are 5 to 15, and the parts of the pure water are 55 to 60.
3. The method of claim 1, wherein the first material is stirred for 30 minutes.
4. The method of claim 1, wherein the second material is stirred for 30 minutes.
5. The method of claim 1, wherein the third material is stirred for 30 minutes.
6. The method of claim 1, wherein the fourth material is stirred for 30 minutes.
7. The method of claim 1, wherein the time for thoroughly stirring the mixture is 2 hours.
8. A smokeless and odorless bleaching agent for die-cast aluminum, which is obtained by the preparation method of any one of claims 1 to 7.
9. Use of a smokeless and odorless bleaching agent for die casting aluminum, characterized in that the die casting aluminum after alkaline washing is bleached with the smokeless and odorless bleaching agent for die casting aluminum according to claim 8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111110047.XA CN113774387A (en) | 2021-09-23 | 2021-09-23 | Smokeless and odorless bleaching agent for die-casting aluminum and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111110047.XA CN113774387A (en) | 2021-09-23 | 2021-09-23 | Smokeless and odorless bleaching agent for die-casting aluminum and preparation method and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113774387A true CN113774387A (en) | 2021-12-10 |
Family
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111110047.XA Pending CN113774387A (en) | 2021-09-23 | 2021-09-23 | Smokeless and odorless bleaching agent for die-casting aluminum and preparation method and application thereof |
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| Country | Link |
|---|---|
| CN (1) | CN113774387A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1152632A (en) * | 1996-10-17 | 1997-06-25 | 周国桢 | One stage method pretreating liquid for aluminium material oxidation pretreatment |
| CN104593793A (en) * | 2015-02-12 | 2015-05-06 | 佛山市仁昌科技有限公司 | Neutralization solution for surface pretreatment of aluminum and aluminum alloy |
| CN104746091A (en) * | 2015-04-28 | 2015-07-01 | 深圳市崇辉表面技术开发有限公司 | Cast aluminum alloy white washing descaling solution |
| CN107254682A (en) * | 2017-06-23 | 2017-10-17 | 深圳市威通科技有限公司 | Scale remover |
| CN107794542A (en) * | 2017-10-24 | 2018-03-13 | 天津圳鹏清洗技术开发有限公司 | A kind of normal temperature scale removal brightening agent of high silicon cast aluminium part |
-
2021
- 2021-09-23 CN CN202111110047.XA patent/CN113774387A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1152632A (en) * | 1996-10-17 | 1997-06-25 | 周国桢 | One stage method pretreating liquid for aluminium material oxidation pretreatment |
| CN104593793A (en) * | 2015-02-12 | 2015-05-06 | 佛山市仁昌科技有限公司 | Neutralization solution for surface pretreatment of aluminum and aluminum alloy |
| CN104746091A (en) * | 2015-04-28 | 2015-07-01 | 深圳市崇辉表面技术开发有限公司 | Cast aluminum alloy white washing descaling solution |
| CN107254682A (en) * | 2017-06-23 | 2017-10-17 | 深圳市威通科技有限公司 | Scale remover |
| CN107794542A (en) * | 2017-10-24 | 2018-03-13 | 天津圳鹏清洗技术开发有限公司 | A kind of normal temperature scale removal brightening agent of high silicon cast aluminium part |
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Application publication date: 20211210 |
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