CN110820028A - Treatment method for recycling waste acid of aluminum profile anodic oxidation tank - Google Patents

Abstract

The invention discloses a treatment method for recycling waste acid of anodizing tank for aluminum profiles. The steps are: (1) Heating reaction: take the waste acid of anodizing tank for aluminum profiles in a strong acid-resistant reaction kettle, turn on cooling water to reflux, and keep stirring, Add the compound, heat the mixture to the reaction temperature and maintain the reaction temperature, and continue to heat and stir; (2) Seed preparation: Take the solid aluminum salt that is incompatible with water and dilute sulfuric acid, which is composed of the acid radical and aluminum ion of the compound, and pulverize it with a stainless steel pulverizer. sieve; (3) seed crystal induction: use the crystal seed to induce the aluminum salt in the reaction solution to form aluminum salt precipitation; (4) natural sedimentation: the temperature of the reaction solution precipitated by the obtained aluminum salt precipitation, control the stirring speed, continue stirring, and take the sedimentation supernatant . ⑸Membrane separation: Precisely filter the sedimentation supernatant with microporous membrane equipment to obtain dealumination acid solution of aluminum profile anodic oxidation tank; ⑹Component adjustment. Low cost, no pollution, sufficient removal of aluminum ions, acid can be recycled, high utilization rate of raw materials, simple process and mechanization.

Description

A kind of treatment method for recycling waste acid of aluminum profile anodizing tank

technical field

The invention belongs to the technical field of aluminum profile processing, and more particularly relates to a treatment method for recycling waste acid of anodizing tank for aluminum profiles. It is suitable for the recycling of waste acid of aluminum profile anodizing tank of any formula in the aluminum profile processing industry, and the recycling treatment of waste acid of aluminum profile electrolytic polishing tank in the aluminum profile processing industry, including sulfuric acid anodizing process, chromic acid anode The waste acid produced by oxidation process, oxalic acid anodizing process and phosphoric acid anodizing process, as well as the recycling treatment of aluminum-containing waste acid in the aluminum profile processing industry.

Background technique

Anodizing is an electrolytic oxidation, in which an oxide film composed of aluminum oxide is usually formed on the surface of the aluminum profile. This film has protective, decorative and other functions. The oxide film is divided into two categories: barrier oxide film and porous oxide film. The barrier oxide film is a dense and non-porous thin oxide film close to the metal surface. The thickness depends on the applied voltage and generally does not exceed 0.1um. The porous oxide film is composed of a barrier layer and a porous layer. The thickness of the barrier layer is related to the applied voltage, and the thickness of the porous layer depends on the amount of electricity passing through. The most commonly used is the porous oxide film. The characteristics of the anodic oxide film are as follows: a. The oxide film has a porous honeycomb structure, and the porosity of the film has a good adsorption capacity. It can be used as the bottom layer of the coating layer and can also be dyed to improve the decorative effect of the metal. b. The hardness of the oxide film is high, and the hardness of the anodic oxide film is very high, and its hardness is about 196 ~ 490HV, because the high hardness determines the wear resistance of the oxide film is very good. c. The corrosion resistance of the oxide film, the aluminum oxide film is very stable in air and soil, and the bonding force with the substrate is also very strong. Generally, after oxidation, it will be dyed and sealed or sprayed to further enhance its corrosion resistance. . d. The bonding force of the oxide film, the bonding force of the oxide film to the base metal is very strong, and it is difficult to separate them mechanically. Even if the film layer bends with the metal, the film layer still maintains a good bond with the base metal, but the oxide film The plasticity of the oxide film is small and the brittleness is large. When the film layer is subjected to large impact load and bending deformation, cracks will occur, so this oxide film is not easy to be used under mechanical action, and can be used as the bottom layer of the paint layer. e. The insulation of the oxide film, the resistance of the anodic oxide film of aluminum is high, the thermal conductivity is also very low, the thermal stability can be as high as 1500 degrees, and the thermal conductivity is 0.419W/(m·K)～1.26W/(m·K) K). Can be used as the dielectric layer of electrolytic capacitors or the insulating layer of electrical products.

Common processes for anodizing aluminum profiles include sulfuric acid anodizing process, chromic acid anodizing process, oxalic acid anodizing process and phosphoric acid anodizing process. The most commonly used is the sulfuric acid anodizing process. The most common sulfuric acid anodizing process for aluminum profiles is: 1. Anodizing acid: 16-18% (mass fraction) sulfuric acid, LY-920 wide temperature oxidant for aluminum profile anodizing 3-5% (mass fraction) and Acid solution composed of pure water; 2. Oxidation temperature 15-25°C (best 18-22°C); 3. Voltage 12-20V, current density 1-1.A/dm2; 4. Oxidation time 10-25min.

As the aluminum profile is corroded by the acid solution in the anodizing tank to produce a protective, decorative and bright surface oxide film, the aluminum on the surface of the aluminum profile will form aluminum ions and dissolve in the acid solution. The aluminum profile is corroded, and the concentration of the acid solution will decrease. When the concentration of aluminum ions in the acid solution of the anodizing tank rises to a certain value and the concentration of the acid solution decreases to a certain value, the high concentration of aluminum ions will produce a strong heating effect and reduce the concentration of the acid solution, resulting in anodizing effect. Seriously reduced, at this time, the acid solution of the anodizing tank needs to be replaced with freshly prepared acid solution, and the waste acid of the anodizing tank is produced. A medium-sized aluminum profile processing company with a daily output of 20-35 tons of waste acid from anodizing tanks. Due to the different formulations and processes of the acid solution in the anodizing tank of each company, the composition of the waste acid in the anodizing tank is also not the same, but the basic composition of the waste acid in the anodizing tank is: sulfuric acid 10-30% (mass fraction), aluminum ions 1.0-3% (mass fraction) and moisture 69-89% (mass fraction) and a small amount of other metal ions.

Due to the high acidity, strong acidity, high concentration, and toxic metal ions contained in the waste acid of the aluminum profile anodizing tank, the treatment cost is extremely high and the difficulty is extremely high, and a large amount of solid waste is produced, which is extremely polluting to the environment. There is currently no effective method for the treatment and utilization of waste acid in anodizing tanks for aluminum profiles. Therefore, studying the treatment technology of waste acid in anodizing tank of aluminum profiles has important and realistic social, economic and environmental significance for the clean production of aluminum profile industry, reducing environmental pollution and increasing economic benefits.

SUMMARY OF THE INVENTION

Aiming at the difficulty, high cost, serious waste pollution and deficiencies in the prior art in the current aluminum profile anodizing tank waste acid treatment, the purpose of the present invention is to provide a treatment for the recycling of aluminum profile anodizing tank waste acid The method has the advantages of low cost, no pollution, sufficient removal of aluminum ions, acid can be recycled, high utilization rate of raw materials, simple process, and mechanized treatment of waste acid recycling of aluminum profile anodizing tank.

In order to achieve the above-mentioned purpose, the present invention has adopted the following technical measures:

The technical idea of the present invention is as follows: by utilizing the property that aluminum ions in the waste acid of the anodizing tank of the aluminum profile can react with the compound to generate aluminum salts that are insoluble in water and dilute acid, the waste acid of the anodizing tank of the aluminum profile is induced by heating reaction and crystal seeds. and the supernatant liquid obtained after natural sedimentation, after membrane separation, filtration and composition adjustment, a recyclable aluminum profile anodic oxidation tank acid solution is obtained.

A processing method for recycling waste acid of aluminum profile anodizing tank, characterized in that, the steps of the processing method are as follows:

1. A processing method for recycling waste acid of anodizing tank of aluminum profile, the steps of which are:

(1) Heating reaction: Take the waste acid of the aluminum profile anodizing tank into a strong acid-resistant reaction kettle or other container, turn on the cooling water to reflux, and add 0.3-25% of its mass compound under the condition of constant stirring, and heat the mixture to The compounding agent dissociation reaction temperature is maintained and the compounding agent dissociation reaction temperature is maintained, and the heating and stirring reaction is continued for 1.0 to 15 hours, so that the compounding agent and aluminum ions are reacted to generate corresponding aluminum salts, and the reaction solution is obtained for use.

The waste acid of the anodizing tank for aluminum profiles is the acid solution that remains after the mixed acid solution used for anodizing aluminum profiles is anodized in the oxidation tank, has high aluminum ion content, cannot be reused, and needs to be discarded. , and its components are: sulfuric acid 10-30% mass fraction, aluminum ion 0.8-3.0% mass fraction, LY-920 wide temperature oxidant for aluminum profile anodizing 0.1-5% mass fraction and moisture 68-86% mass fraction; the The compounding agent is one of analytically pure or chemically pure dodecylbenzenesulfonic acid, phytic acid, oxalic acid, phosphoric acid, silicic acid, polysilicic acid, fluorosilicic acid and hydrofluoric acid, or two to eight kinds of A mixture in any proportion; the dissociation reaction temperature of the compounding agent is a temperature that can promote the formation of the corresponding aluminum salt, and its range is 15-120°C.

Preferably, the waste acid of the anodizing tank for aluminum profiles is the mixed acid solution used for anodizing aluminum profiles that remains after anodizing the aluminum profiles in the oxidation tank, has a high content of aluminum ions, cannot be reused, and needs to be discarded. The main components of the acid solution are: sulfuric acid 13-25% (mass fraction), aluminum ions 1.2-2.5% (mass fraction), LY-920 wide temperature oxidant for aluminum profile anodizing 0.5-3% (mass fraction) and Moisture 70-85.3% (mass fraction); the compounding agent is one of analytically pure dodecylbenzenesulfonic acid, phytic acid, phosphoric acid, silicic acid, polysilicic acid, fluorosilicic acid and hydrofluoric acid , or two kinds of mixtures in any proportion, or three kinds of mixtures in any proportion; the dissociation reaction temperature of the compounding agent is the temperature that can promote the formation of the corresponding aluminum salt, and its range is 30～110℃.

(2) Preparation of seed crystals: Take the solid aluminum salt that is incompatible with water and dilute sulfuric acid, which is composed of the corresponding compound acid radical and aluminum ion, and pulverize it with a stainless steel pulverizer. After the pulverized material is sieved through a standard sieve, the aluminum salt seed crystal .

Described solid aluminium salt is analytically pure or chemically pure aluminium dodecylbenzenesulfonate, aluminium phytate, aluminium oxalate, aluminium phosphate, aluminium silicate, aluminium polysilicate, aluminium fluorosilicate and aluminium hydrofluorate Any one, or a mixture of two to eight in any proportion; the sieving is 40-600 mesh.

Preferably, the solid aluminum salt is one of analytically pure aluminum dodecylbenzenesulfonate, aluminum phytate, aluminum phosphate, aluminum silicate, aluminum polysilicate, aluminum fluorosilicate and aluminum hydrofluorate One kind, or a mixture of two kinds to eight kinds in any proportion; the standard sieve sieving is sieving through a standard sieve of 80-400 meshes.

(3) Induction of seed crystals: reduce the temperature of the reaction solution obtained in step (1) to 0 to 45 °C and maintain it at 0 to 45 °C, and under the condition of constant stirring, add to the reaction solution the mass fraction obtained by step (2) that can play an inducing effect. and continue stirring for 1.0 to 25 hours, so that the seed crystal induces the aluminum salt in the reaction solution to form aluminum salt precipitation, so as to obtain a reaction solution in which the aluminum salt is precipitated.

The mass fraction that can play an inducing role is the mass fraction that can play a role in inducing crystal formation, and its range is 0.05-5%.

Preferably, the mass fraction capable of inducing crystallization is the mass fraction capable of inducing crystal formation, and its range is 0.05-5%.

Preferably, the appropriate mass fraction is the mass fraction that can induce the formation of crystallization, and its range is 0.1-2%.

(4) Natural sedimentation: maintain the temperature of the reaction solution obtained by the precipitation of the aluminum salt obtained in step (3) at 0 to 40 ° C, control the sedimentation stirring speed, continue stirring for 5 to 45 hours, stop stirring, and allow the sediment to settle naturally for 3 to 15 hours. Reserve the supernatant.

The settling stirring speed is the stirring speed at which the aluminum salt can settle, and the range is 1-50 rpm.

Preferably, the settling stirring speed is the stirring speed at which the aluminum salt can settle, and the range is 5-40 rpm.

(5) Membrane separation: Precisely filter the sedimentation supernatant obtained in step (4) with a microporous membrane equipment, and obtain the dealumination acid solution of the aluminum profile anodizing tank for use.

In the microporous membrane device, the membrane material is silicon carbide, the membrane component is in the form of a honeycomb-type inner tubular membrane, and the membrane pores are 1, 0.5, 0.1 and 0.04 μm in size.

Preferably, in the microporous membrane device, the membrane material is silicon carbide, the membrane module is in the form of a honeycomb-type inner tubular membrane, and the membrane pore size is 0.1 and 0.04 μm.

⑹Component adjustment: analyze and measure the sulfuric acid mass percentage content of the aluminum profile anodizing tank dealumination acid solution obtained in step (5), according to the aluminum profile anodizing process aluminum profile anodizing tank acid solution The sulfuric acid mass percentage content, add concentrated sulfuric acid And the LY-920 wide-temperature oxidant specially used for anodizing aluminum profiles and stirring evenly, the acid solution of the anodizing tank can be recycled, which is used for the anodizing of the next batch of aluminum profiles.

The concentrated sulfuric acid is analytically pure or chemically pure sulfuric acid with a mass fraction of 98%.

Preferably, the concentrated sulfuric acid is analytically pure or chemically pure sulfuric acid with a mass fraction of 98%.

Through the technical measures of the above six steps, the most critical are step (2) heating reaction, step (3) seed crystal induction and step (4) membrane separation, mainly through the temperature-controlled heating reaction to solve the acid dissociation that can generate insoluble aluminum salt with aluminum to generate Insoluble aluminum salt, the use of insoluble aluminum salt seeds to induce insoluble aluminum salt crystallization solves the solid phase precipitation of insoluble aluminum salt, and the strong corrosion-resistant silicon carbide membrane filtration solves the problem of high acid concentration and strong acid. Technical problems and difficulties such as filtration of insoluble impurities in aluminum waste acid. It mainly achieves the salt formation and removal of aluminum ions that hinder the recycling of the waste acid solution of the aluminum profile anodizing tank, and the complete separation of insoluble aluminum salts and insoluble impurities with tiny particles in the aluminum profile anodizing tank's dealumination acid solution and the adjustment of components. The technical effect of recycling waste acid from dealumination of aluminum profile anodizing tank is realized. Since the waste acid of the acid solution of the aluminum profile anodizing tank is directly discharged as waste after neutralization with alkali, there is almost no technical solution. Therefore, the progress of the present invention compared with the existing technology is reflected in innovation, resource utilization and environmental protection. aspect.

Through the technical treatment of the invention, the sulfuric acid retention rate in the waste acid of the anodizing tank for aluminum profiles is 100%; the total acid content increases; the removal rate of aluminum ions is greater than or equal to 85%; the removal rate of insoluble impurities is 100%; the appearance is colorless and clear transparent. The acid solution of the anodizing tank obtained by adjusting the composition of the dealumination acid solution in the anodizing tank for aluminum profiles can be used for the anodizing of the next batch of aluminum profiles.

Compared with the prior art, the advantages and beneficial effects of the method of the present invention are:

It has low cost, no pollution, sufficient removal of aluminum ions, acid can be recycled, high utilization rate of raw materials, simple process, mechanized treatment, and can be adapted to large and small production scales.

Aiming at the difficulties in the treatment of waste acid in the current aluminum profile anodizing tank, serious waste and pollution and the deficiencies in the prior art, the purpose of the present invention is to provide a low-cost, pollution-free, acid recyclable, and raw material utilization rate. A treatment method for recycling waste acid of aluminum profile anodizing tank with high, simple and mechanized process.

The recyclable waste acid of the anodizing tank for aluminum profiles treated by the invention is a colorless and clear uniform liquid, the aluminum ion that affects the anodizing effect is removed, and the sulfuric acid is retained, and the effect of recycling is the same as that of the freshly prepared anodizing acid solution. In the same way, it avoids the strong environmental pollution of waste acid, high treatment cost and waste of useful resources.

Description of drawings

Fig. 1 is a process flow diagram of a treatment method for recycling waste acid of anodizing tank of aluminum profile.

Detailed ways

The present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

Example 1:

A processing method for recycling waste acid of anodizing tank of aluminum profile, the steps of which are:

(1) Heating reaction: take the main components as sulfuric acid 19% (mass fraction), aluminum ions 1.8% (mass fraction), LY-920 wide temperature oxidant for aluminum profile anodizing 1.7% (mass fraction) and moisture 77.5% (mass fraction) 500 grams of waste acid from anodizing tank of aluminum profile was placed in a grinding-mouthed conical flask, and under the stirring condition of a stirring speed of 100 rpm, dodecylbenzene sulfonic acid of 1.5% by mass was added, and the cold water reflux was turned on, and the mixture was heated to 85 ℃ and maintain 85 ℃, continue to heat and stir the reaction for 8 hours, make the dodecylbenzene sulfonic acid in it react with the aluminum ion to generate the corresponding aluminum dodecyl benzene sulfonate, and obtain the reaction solution for subsequent use.

(2) Seed preparation: take solid analytically pure aluminum dodecylbenzenesulfonate, pulverize it with a stainless steel pulverizer, and pass the pulverized material through a 200-mesh standard sieve to obtain aluminum dodecylbenzenesulfonate seed crystals.

(3) Seed induction: the temperature of the reaction solution obtained in step (1) is lowered to 25°C and maintained at 25°C. Under the stirring condition of the stirring speed of 200 rpm, dodecylbenzenesulfonic acid with a mass fraction of 0.5% is added to the reaction solution. The aluminum seed crystal was stirred for 15 hours, so that the seed crystal induced the aluminum salt in the reaction solution to fully form the aluminum dodecylbenzenesulfonate precipitation, and the reaction solution in which the aluminum salt was precipitated was obtained.

(4) Natural sedimentation: maintaining the temperature of the reaction solution obtained in step (3) by the precipitation of the aluminum salt at 25 ° C, under the stirring condition of the stirring speed of 20 rpm, after continuing to stir for 25 hours, stop stirring and let the sediment settle naturally for 10 hours. Serum backup.

⑸Membrane separation: use the microporous membrane equipment whose membrane material is silicon carbide, the membrane hole is 0.04μm and the membrane module form is honeycomb type inner tubular membrane. mass fraction) and 18% (mass fraction) of aluminum profile anodizing tank dealumination acid solution 493 grams.

⑹Component adjustment: According to the requirements of the mass percentage of sulfuric acid in the acid solution of the aluminum profile anodizing tank required by the aluminum profile anodizing process, the analytical pure concentrated sulfuric acid and the special LY-920 wide temperature oxidant for aluminum profile anodizing shall be added and stirred evenly , that is, the recyclable acid solution of anodizing tank is obtained for the anodizing of the next batch of aluminum profiles.

It has been determined that the sulfuric acid retention rate is 100%, the removal rate of aluminum ions is ≥85%, the removal rate of insoluble impurities is 100%, and the appearance is clear and transparent. The acid solution of the anodizing tank obtained by adjusting the composition of the dealumination acid solution in the anodizing tank for aluminum profiles can be used for the anodizing of the next batch of aluminum profiles.

Example 2:

A processing method for recycling waste acid of anodizing tank of aluminum profile, the steps of which are:

(1) Heating reaction: take the main composition as sulfuric acid 16% (mass fraction), aluminum ion 2.1% (mass fraction), LY-920 wide temperature oxidant for aluminum profile anodizing 1.3% (mass fraction) and moisture 80.6% (mass fraction) 650 grams of waste acid from the anodizing tank of aluminum profile was put into a grinding-mouthed conical flask, and under the stirring condition of the stirring speed of 130 rpm, phytic acid of 2.5% by mass was added, the cold water reflux was turned on, and the mixture was heated to 90 ° C and maintained at 90 ° C , continue heating and stirring reaction for 9 hours, make the phytic acid in it react with aluminum ion to generate corresponding aluminum phytate, and obtain the reaction solution for subsequent use.

(2) Seed preparation: take solid analytically pure aluminum phytate, pulverize it with a stainless steel pulverizer, and sieve the pulverized material through a 160-mesh standard sieve to obtain aluminum phytate seed crystals.

(3) Seed crystal induction: reduce the temperature of the reaction solution obtained in step (1) to 30 °C and maintain it at 30 °C. Under the stirring condition of the stirring speed of 200 rpm, add 0.3% mass fraction of aluminum phytate seeds to the reaction solution, and continue Stir for 15 hours, so that the aluminum salt in the seed crystal induces the aluminum salt in the reaction solution to fully form the aluminum phytate precipitation to obtain the reaction solution in which the aluminum salt is precipitated.

(4) Natural sedimentation: maintain the temperature of the reaction solution obtained in step (3) to precipitate out the aluminum salt at 30 ° C, under the stirring condition of the stirring speed of 15 rpm, continue stirring for 20 hours, stop stirring, and let the sedimentation naturally settle for 13 hours. Serum backup.

⑸Membrane separation: use the microporous membrane equipment whose membrane material is silicon carbide, the membrane pores are 0.1 μm, and the membrane module form is honeycomb type inner tubular membrane. mass fraction) and sulfuric acid content of 14.9% (mass fraction) aluminum profile anodic oxidation tank dealumination acid solution 639 grams.

⑹Component adjustment: According to the requirements of the mass percentage of sulfuric acid in the acid solution of the aluminum profile anodizing tank required by the aluminum profile anodizing process, the analytical pure concentrated sulfuric acid and the special LY-920 wide temperature oxidant for aluminum profile anodizing shall be added and stirred evenly , that is, the recyclable acid solution of anodizing tank is obtained for the anodizing of the next batch of aluminum profiles.

It has been determined that the sulfuric acid retention rate is 100%, the removal rate of aluminum ions is ≥85%, the removal rate of insoluble impurities is 100%, and the appearance is clear and transparent. The acid solution of the anodizing tank obtained by adjusting the composition of the dealumination acid solution in the anodizing tank for aluminum profiles can be used for the anodizing of the next batch of aluminum profiles.

Example 3:

A processing method for recycling waste acid of anodizing tank of aluminum profile, the steps of which are:

(1) Heating reaction: take the main components as sulfuric acid 20.5% (mass fraction), aluminum ions 2.4% (mass fraction), LY-920 wide temperature oxidant for aluminum profile anodizing 0.7% (mass fraction) and moisture 76.4% (mass fraction) 832 grams of waste acid from the anodizing tank of aluminum profile was put into a grinding-mouthed conical flask, and under the stirring condition of a stirring speed of 150 rpm, oxalic acid with a mass fraction of 3.0% was added, and the cold water reflux was turned on, and the mixture was heated to 80 ° C and maintained at 80 ° C , continue to heat and stir the reaction for 12 hours, so that the oxalic acid in it reacts with the aluminum ion to generate the corresponding aluminum oxalate, and the reaction solution is obtained for subsequent use.

(2) Seed preparation: take solid analytically pure aluminum oxalate, pulverize it with a stainless steel pulverizer, and sieve the pulverized material through a 300-mesh standard sieve to obtain aluminum oxalate seed crystals.

(3) Seed crystal induction: reduce the temperature of the reaction solution obtained in step (1) to 15 °C and maintain it at 15 °C, under the stirring condition of the stirring speed of 160 rpm, add 0.25% mass fraction of aluminum oxalate seeds to the reaction solution, and continue stirring. After 20 hours, the aluminum salt in the seed crystal induced reaction solution is fully formed into aluminum oxalate precipitation to obtain a reaction solution in which the aluminum salt is precipitated.

(4) Natural sedimentation: maintaining the temperature of the reaction solution obtained in step (3) by the precipitation of the aluminum salt at 15 ° C, under the stirring condition of the stirring speed of 25 rpm, after continuing to stir for 20 hours, stop stirring, and let the sediment settle naturally for 8 hours. Serum backup.

⑸Membrane separation: use the microporous membrane equipment whose membrane material is silicon carbide, the membrane pore is 0.04μm, and the membrane module form is honeycomb type inner tubular membrane. mass fraction) and the sulfuric acid content of 19.2% (mass fraction) aluminum profile anodic oxidation tank dealumination acid solution 812 grams.

⑹Component adjustment: According to the requirements of the mass percentage of sulfuric acid in the acid solution of the aluminum profile anodizing tank required by the aluminum profile anodizing process, the analytical pure concentrated sulfuric acid and the special LY-920 wide temperature oxidant for aluminum profile anodizing shall be added and stirred evenly , that is, the recyclable acid solution of anodizing tank is obtained for the anodizing of the next batch of aluminum profiles.

It has been determined that the sulfuric acid retention rate is 100%, the removal rate of aluminum ions is ≥85%, the removal rate of insoluble impurities is 100%, and the appearance is clear and transparent. The acid solution of the anodizing tank obtained by adjusting the composition of the dealumination acid solution in the anodizing tank for aluminum profiles can be used for the anodizing of the next batch of aluminum profiles.

Example 4:

A processing method for recycling waste acid of anodizing tank of aluminum profile, the steps of which are:

(1) Heating reaction: take the main components as sulfuric acid 19% (mass fraction), aluminum ions 1.8% (mass fraction), LY-920 wide temperature oxidant for aluminum profile anodizing 1.7% (mass fraction) and moisture 77.5% (mass fraction) 500 grams of waste acid from anodizing tank of aluminum profile was put into a grinding-mouthed conical flask, and under the stirring condition of a stirring speed of 100 rpm, phosphoric acid with a mass fraction of 9.5% (phosphoric acid with a mass percentage concentration of 85%) was added, and the cold water was turned on. Under reflux, the mixture was heated to 85° C. and maintained at 85° C., and the heating and stirring reaction was continued for 8 hours, so that phosphoric acid and aluminum ions were reacted to generate corresponding aluminum phosphate, and the reaction solution was obtained for use.

(2) Seed preparation: take solid analytically pure aluminum phosphate, pulverize it with a stainless steel pulverizer, and sieve the pulverized material through a 200-mesh standard sieve to obtain aluminum phosphate seed crystals.

(3) Seed crystal induction: reduce the temperature of the reaction solution obtained in step (1) to 25 °C and maintain it at 25 °C. Under the stirring condition of the stirring speed of 200 rpm, add aluminum phosphate seeds with a mass fraction of 0.5% to the reaction solution, and continue stirring. After 15 hours, the aluminum salt in the seed crystal induced reaction solution is fully formed into aluminum phosphate precipitation to obtain a reaction solution in which the aluminum salt is precipitated.

(4) Natural sedimentation: maintaining the temperature of the reaction solution obtained in step (3) by the precipitation of the aluminum salt at 25 ° C, under the stirring condition of the stirring speed of 20 rpm, after continuing to stir for 25 hours, stop stirring and let the sediment settle naturally for 10 hours. Serum backup.

⑸Membrane separation: use the microporous membrane equipment whose membrane material is silicon carbide, the membrane pore is 0.04μm, and the membrane module form is honeycomb type inner tubular membrane. mass fraction) and 18% (mass fraction) of aluminum profile anodizing tank dealumination acid solution 493 grams.

⑹Component adjustment: According to the requirements of the mass percentage of sulfuric acid in the acid solution of the aluminum profile anodizing tank required by the aluminum profile anodizing process, the analytical pure concentrated sulfuric acid and the special LY-920 wide temperature oxidant for aluminum profile anodizing shall be added and stirred evenly , that is, the recyclable acid solution of anodizing tank is obtained for the anodizing of the next batch of aluminum profiles.

It has been determined that the sulfuric acid retention rate is 100%, the removal rate of aluminum ions is ≥85%, the removal rate of insoluble impurities is 100%, and the appearance is clear and transparent. The acid solution of the anodizing tank obtained by adjusting the composition of the dealumination acid solution in the anodizing tank for aluminum profiles can be used for the anodizing of the next batch of aluminum profiles.

Example 5:

A processing method for recycling waste acid of anodizing tank of aluminum profile, the steps of which are:

(1) Heating reaction: take the main components as sulfuric acid 19% (mass fraction), aluminum ions 1.8% (mass fraction), LY-920 wide temperature oxidant for aluminum profile anodizing 1.7% (mass fraction) and moisture 77.5% (mass fraction) 500 grams of waste acid from the anodizing tank of aluminum profile was put into a grinding-mouthed conical flask, and under the stirring condition of the stirring speed of 100 rpm, silicic acid with a mass fraction of 6.5% was added, and the cold water reflux was turned on, and the mixture was heated to 85 ° C and maintained at 85 ℃, continue to heat and stir the reaction for 8 hours, so that the silicic acid and aluminum ions in it react to generate the corresponding aluminum silicate, and the reaction solution is obtained for subsequent use.

(2) Seed preparation: take solid analytically pure aluminum silicate, pulverize it with a stainless steel pulverizer, and sieve the pulverized material through a 200-mesh standard sieve to obtain aluminum silicate seeds.

(3) Seed crystal induction: reduce the temperature of the reaction solution obtained in step (1) to 25 ° C and maintain it at 25 ° C, under the stirring condition of the stirring speed of 200 rpm, add 0.5% mass fraction of aluminum silicate seeds to the reaction solution, and continue Stir for 15 hours, so that the seed crystal induces the aluminum salt in the reaction solution to fully form aluminum silicate precipitation to obtain a reaction solution in which the aluminum salt is precipitated.

(4) Natural sedimentation: maintaining the temperature of the reaction solution obtained in step (3) by the precipitation of the aluminum salt at 25 ° C, under the stirring condition of the stirring speed of 20 rpm, after continuing to stir for 25 hours, stop stirring and let the sediment settle naturally for 10 hours. Serum backup.

⑸Membrane separation: use the microporous membrane equipment whose membrane material is silicon carbide, the membrane pore is 0.04μm, and the membrane module form is honeycomb type inner tubular membrane. mass fraction) and 18% (mass fraction) of aluminum profile anodizing tank dealumination acid solution 493 grams.

⑹Component adjustment: According to the requirements of the mass percentage of sulfuric acid in the acid solution of the aluminum profile anodizing tank required by the aluminum profile anodizing process, the analytical pure concentrated sulfuric acid and the special LY-920 wide temperature oxidant for aluminum profile anodizing shall be added and stirred evenly , that is, the recyclable acid solution of anodizing tank is obtained for the anodizing of the next batch of aluminum profiles.

It has been determined that the sulfuric acid retention rate is 100%, the removal rate of aluminum ions is ≥85%, the removal rate of insoluble impurities is 100%, and the appearance is clear and transparent. The acid solution of the anodizing tank obtained by adjusting the composition of the dealumination acid solution in the anodizing tank for aluminum profiles can be used for the anodizing of the next batch of aluminum profiles.

Example 6:

A processing method for recycling waste acid of anodizing tank of aluminum profile, the steps of which are:

(1) Heating reaction: take the main components as sulfuric acid 19% (mass fraction), aluminum ions 1.8% (mass fraction), LY-920 wide temperature oxidant for aluminum profile anodizing 1.7% (mass fraction) and moisture 77.5% (mass fraction) 500 grams of waste acid from the anodizing tank of aluminum profile was placed in a grinding-mouthed conical flask, and under the stirring condition of a stirring speed of 100 rpm, polysilicic acid with a mass fraction of 8.5% was added, the cold water reflux was turned on, and the mixture was heated to 85 ° C and maintained 85° C., continue to heat and stir for 8 hours to react the polysilicic acid with aluminum ions to generate corresponding polyaluminum silicate, and obtain the reaction solution for later use.

(2) Seed preparation: Take solid analytically pure aluminum polysilicate, pulverize it with a stainless steel pulverizer, and sieve the pulverized material through a 200-mesh standard sieve to obtain polyaluminum silicate seeds.

(3) Seed induction: the temperature of the reaction solution obtained in step (1) is lowered to 25°C and maintained at 25°C, and under the stirring condition of a stirring speed of 200 rpm, polyaluminosilicate seeds with a mass fraction of 0.5% are added to the reaction solution, Stirring is continued for 15 hours, so that the aluminum salt in the seed crystal induces the aluminum salt in the reaction solution to fully form polyaluminum silicate precipitation, and the reaction solution in which the aluminum salt is precipitated is obtained.

(4) Natural sedimentation: maintaining the temperature of the reaction solution obtained in step (3) by the precipitation of the aluminum salt at 25 ° C, under the stirring condition of the stirring speed of 20 rpm, after continuing to stir for 25 hours, stop stirring and let the sediment settle naturally for 10 hours. Serum backup.

⑸Membrane separation: use the microporous membrane equipment whose membrane material is silicon carbide, the membrane pore is 0.04μm, and the membrane module form is honeycomb type inner tubular membrane. mass fraction) and 18% (mass fraction) of aluminum profile anodizing tank dealumination acid solution 493 grams.

⑹ Composition adjustment: According to the requirements of the mass percentage of sulfuric acid in the acid solution of the aluminum profile anodizing tank required by the aluminum profile anodizing process, the analytical pure concentrated sulfuric acid and the special LY-920 wide temperature oxidant for aluminum profile anodizing should be added. After stirring evenly, a recyclable acid solution of anodizing tank is obtained, which is used for the anodizing of the next batch of aluminum profiles.

It has been determined that the sulfuric acid retention rate is 100%, the removal rate of aluminum ions is ≥85%, the removal rate of insoluble impurities is 100%, and the appearance is clear and transparent. The acid solution of the anodizing tank obtained by adjusting the composition of the dealumination acid solution in the anodizing tank for aluminum profiles can be used for the anodizing of the next batch of aluminum profiles.

Example 7:

A processing method for recycling waste acid of anodizing tank of aluminum profile, the steps of which are:

(1) Heating reaction: take the main components as sulfuric acid 19% (mass fraction), aluminum ions 1.8% (mass fraction), LY-920 wide temperature oxidant for aluminum profile anodizing 1.7% (mass fraction) and moisture 77.5% (mass fraction) 500 grams of waste acid from the anodizing tank of aluminum profile was placed in a grinding-mouthed conical flask, and under the stirring condition of the stirring speed of 100 rpm, 15.5% fluorosilicic acid (aqueous solution with a mass fraction of 30% fluorosilicic acid) was added, Turn on the cold water to reflux, heat the mixture to 85°C and maintain it at 85°C, continue to heat and stir for 8 hours to react the fluorosilicic acid with aluminum ions to generate the corresponding aluminum fluorosilicate, and obtain the reaction solution for later use.

(2) Seed preparation: Take solid analytically pure aluminum fluorosilicate and pulverize it with a stainless steel pulverizer. After the pulverized material is sieved through a 200-mesh standard sieve, aluminum fluorosilicate seeds are obtained.

(3) Seed induction: reduce the temperature of the reaction solution obtained in step (1) to 25 °C and maintain it at 25 °C, under the stirring condition of the stirring speed of 200 rpm, add 0.5% mass fraction of aluminum fluorosilicate seeds to the reaction solution, Stirring is continued for 15 hours, so that the aluminum salt in the seed crystal induces the aluminum salt in the reaction solution to fully form the aluminum fluorosilicate precipitate, and the reaction solution in which the aluminum salt is precipitated is obtained.

(4) Natural sedimentation: maintaining the temperature of the reaction solution obtained in step (3) by the precipitation of the aluminum salt at 25 ° C, under the stirring condition of the stirring speed of 20 rpm, after continuing to stir for 25 hours, stop stirring and let the sediment settle naturally for 10 hours. Serum backup.

⑸Membrane separation: use the microporous membrane equipment whose membrane material is silicon carbide, the membrane pore is 0.04μm, and the membrane module form is honeycomb type inner tubular membrane. mass fraction) and sulfuric acid content of 14.1% (mass fraction) aluminum profile anodic oxidation tank dealumination acid solution 561 grams.

⑹Component adjustment: According to the requirements of the mass percentage of sulfuric acid in the acid solution of the aluminum profile anodizing tank required by the aluminum profile anodizing process, the analytical pure concentrated sulfuric acid and the special LY-920 wide temperature oxidant for aluminum profile anodizing shall be added and stirred evenly , that is, the recyclable acid solution of anodizing tank is obtained for the anodizing of the next batch of aluminum profiles.

It has been determined that the sulfuric acid retention rate is 100%, the removal rate of aluminum ions is ≥85%, the removal rate of insoluble impurities is 100%, and the appearance is clear and transparent. The acid solution of the anodizing tank obtained by adjusting the composition of the dealumination acid solution in the anodizing tank for aluminum profiles can be used for the anodizing of the next batch of aluminum profiles.

Example 8:

A processing method for recycling waste acid of anodizing tank of aluminum profile, the steps of which are:

(1) Heating reaction: take the main components as sulfuric acid 19% (mass fraction), aluminum ions 1.8% (mass fraction), LY-920 wide temperature oxidant for aluminum profile anodizing 1.7% (mass fraction) and moisture 77.5% (mass fraction) 500 grams of waste acid from the anodizing tank of aluminum profile was placed in a grinding-mouthed conical flask, and under the stirring condition of a stirring speed of 100 rpm, 2.5% of its mass fraction of hydrofluoric acid (which was an aqueous solution of 40% of hydrofluoric acid mass percentage concentration) was added. ), turn on the cold water reflux, heat the mixture to 85 ℃ and maintain 85 ℃, continue to heat and stir for 8 hours, make the hydrofluoric acid in it react with aluminum ion to generate corresponding aluminum fluoride, and obtain the reaction solution for subsequent use.

(2) Seed preparation: take solid analytically pure aluminum fluoride, pulverize it with a stainless steel pulverizer, and sieve the pulverized material through a 200-mesh standard sieve to obtain aluminum fluoride seed crystals.

(3) Seed crystal induction: reduce the temperature of the reaction solution obtained in step (1) to 25 °C and maintain it at 25 °C. Under the stirring condition of the stirring speed of 200 rpm, add 0.5% mass fraction of aluminum fluoride seed crystals to the reaction solution, and continue Stir for 15 hours, so that the seed crystal induces the aluminum salt in the reaction solution to fully form aluminum fluoride precipitation to obtain the reaction solution in which the aluminum salt is precipitated.

(4) Natural sedimentation: maintaining the temperature of the reaction solution obtained in step (3) by the precipitation of the aluminum salt at 25 ° C, under the stirring condition of the stirring speed of 20 rpm, after continuing to stir for 25 hours, stop stirring and let the sediment settle naturally for 10 hours. Serum backup.

⑸Membrane separation: use the microporous membrane equipment whose membrane material is silicon carbide, the membrane pore is 0.04μm, and the membrane module form is honeycomb type inner tubular membrane. mass fraction) and sulfuric acid content of 16.8% (mass fraction) aluminum profile anodic oxidation tank dealumination acid solution 503 grams.

⑹Component adjustment: According to the requirements of the mass percentage of sulfuric acid in the acid solution of the aluminum profile anodizing tank required by the aluminum profile anodizing process, the analytical pure concentrated sulfuric acid and the special LY-920 wide temperature oxidant for aluminum profile anodizing shall be added and stirred evenly , that is, the recyclable acid solution of anodizing tank is obtained for the anodizing of the next batch of aluminum profiles.

It has been determined that the sulfuric acid retention rate is 100%, the removal rate of aluminum ions is ≥85%, the removal rate of insoluble impurities is 100%, and the appearance is clear and transparent. The acid solution of the anodizing tank obtained by adjusting the composition of the dealumination acid solution in the anodizing tank for aluminum profiles can be used for the anodizing of the next batch of aluminum profiles.

Example 9:

A processing method for recycling waste acid of anodizing tank of aluminum profile, the steps of which are:

(1) Heating reaction: take the main composition as sulfuric acid 16.5% (mass fraction), aluminum ion 2.0% (mass fraction), LY-920 wide temperature oxidant for aluminum profile anodizing 0.9% (mass fraction) and moisture 80.6% (mass fraction) 1760 grams of waste acid from anodizing tank of aluminum profile was put into a ground-mouthed conical flask, and under the stirring condition of a stirring speed of 100 rpm, 0.5% of dodecylbenzene sulfonic acid and 7.5% of fluorosilicon were added. acid (aqueous solution with a mass fraction of fluorosilicic acid of 30%), turn on cold water reflux, heat the mixture to 89 ° C and maintain 89 ° C, continue to heat and stir for 12 hours, so that the dodecylbenzenesulfonic acid and fluorosilicic acid in it Reaction with aluminum ions generates corresponding aluminum dodecylbenzenesulfonate and aluminum fluorosilicate, and the reaction solution is obtained for subsequent use.

(2) Seed crystal preparation: Take solid analytically pure aluminum dodecylbenzenesulfonate and aluminum fluorosilicate, mix them in a mass ratio of 1:3, and pulverize them with a stainless steel pulverizer. A mixed seed crystal of aluminum dodecylbenzenesulfonate and aluminum fluorosilicate is obtained.

(3) Seed induction: reduce the temperature of the reaction solution obtained in step (1) to 25° C. and maintain it at 15° C. Under the stirring condition of the stirring speed of 200 rpm, add a mixed seed crystal with a mass fraction of 0.3% to the reaction solution, and continue to stir for 18 hours, the seed crystal induces the aluminum salt in the reaction solution to fully form the precipitation of aluminum dodecylbenzenesulfonate and aluminum fluorosilicate to obtain a reaction solution in which the aluminum salt is precipitated.

(4) Natural sedimentation: maintain the temperature of the reaction solution obtained in step (3) by the precipitation of the aluminum salt at 15 ° C, under the stirring condition of the stirring speed of 20 rpm, continue stirring for 25 hours, stop stirring, and let the sedimentation naturally settle for 10 hours. Serum backup.

⑸Membrane separation: use the microporous membrane equipment whose membrane material is silicon carbide, the membrane pore is 0.04μm, and the membrane module form is honeycomb type inner tubular membrane. mass fraction) and sulfuric acid content of 14.1% (mass fraction) aluminum profile anodic oxidation tank dealumination acid solution 1859 grams.

⑹Component adjustment: According to the requirements of the mass percentage of sulfuric acid in the acid solution of the aluminum profile anodizing tank required by the aluminum profile anodizing process, the analytical pure concentrated sulfuric acid and the special LY-920 wide temperature oxidant for aluminum profile anodizing shall be added and stirred evenly , that is, the recyclable acid solution of anodizing tank is obtained for the anodizing of the next batch of aluminum profiles.

It has been determined that the sulfuric acid retention rate is 100%, the removal rate of aluminum ions is ≥85%, the removal rate of insoluble impurities is 100%, and the appearance is clear and transparent. The acid solution of the anodizing tank obtained by adjusting the composition of the dealumination acid solution in the anodizing tank for aluminum profiles can be used for the anodizing of the next batch of aluminum profiles.

Example 10:

A processing method for recycling waste acid of anodizing tank of aluminum profile, the steps of which are:

(1) Heating reaction: take the main components as sulfuric acid 17.2% (mass fraction), aluminum ions 2.2% (mass fraction), LY-920 wide temperature oxidant for aluminum profile anodizing 1.1% (mass fraction) and moisture 79.5% (mass fraction) 5280 grams of waste acid from anodizing tank of aluminum profile was put into a ground conical flask, and under the stirring condition of stirring speed of 100 rpm, 5.5% phosphoric acid and 3.5% fluorosilicic acid (mass of fluorosilicic acid) were added. Aqueous solution with a fraction of 30%), turn on the cold water reflux, heat the mixture to 95 ° C and maintain it at 95 ° C, continue to heat and stir for 11 hours, so that the phosphoric acid and fluorosilicic acid in it react with aluminum ions to form the corresponding aluminum phosphate and fluorosilicon aluminum acid, and the reaction solution was prepared for later use.

(2) Seed preparation: Take solid analytically pure aluminum phosphate and aluminum fluorosilicate, mix them in a mass ratio of 2:1, pulverize them with a stainless steel pulverizer, and sieve the pulverized material through a 300-mesh standard sieve to obtain Mixed aluminum seeds composed of aluminum fluorosilicate.

(3) Seed induction: reduce the temperature of the reaction solution obtained in step (1) to 10 °C and maintain it at 10 °C. Under the stirring condition of the stirring speed of 220 rpm, add a mixed seed crystal with a mass fraction of 0.3% to the reaction solution, and continue to stir for 16 hours, the seed crystal induces the aluminum salt in the reaction solution to fully form aluminum phosphate and aluminum fluorosilicate precipitation to obtain a reaction solution in which the aluminum salt is precipitated.

(4) Natural sedimentation: maintain the temperature of the reaction solution obtained in step (3) to precipitate out the aluminum salt at 10 ° C, under the stirring condition of the stirring speed of 25 rpm, continue stirring for 22 hours, stop stirring, and let the sedimentation naturally settle for 12 hours. Serum backup.

⑸Membrane separation: use the microporous membrane equipment whose membrane material is silicon carbide, the membrane pore is 0.04μm, and the membrane module form is honeycomb type inner tubular membrane. mass fraction) and sulfuric acid content of 15.3% (mass fraction) aluminum profile anodic oxidation tank dealumination acid solution 5410 grams.

⑹Component adjustment: According to the requirements of the mass percentage of sulfuric acid in the acid solution of the aluminum profile anodizing tank required by the aluminum profile anodizing process, the analytical pure concentrated sulfuric acid and the special LY-920 wide temperature oxidant for aluminum profile anodizing shall be added and stirred evenly , that is, the recyclable acid solution of anodizing tank is obtained for the anodizing of the next batch of aluminum profiles.

It has been determined that the sulfuric acid retention rate is 100%, the removal rate of aluminum ions is ≥85%, the removal rate of insoluble impurities is 100%, and the appearance is clear and transparent. The acid solution of the anodizing tank obtained by adjusting the composition of the dealumination acid solution in the anodizing tank for aluminum profiles can be used for the anodizing of the next batch of aluminum profiles.

The specific embodiments described in this specification are merely illustrative of the spirit of the present invention. Those skilled in the art to which the present invention pertains can make various modifications or additions to the described specific embodiments or substitute in similar manners, but will not deviate from the spirit of the present invention or go beyond the definitions of the appended claims range.

Claims (7)

1.A treatment method for recycling waste acid of an aluminum profile anodic oxidation tank comprises the following steps:

⑴ heating reaction, namely putting the waste acid of the aluminum profile anodic oxidation tank into a strong acid resistant reaction kettle or other container, starting cooling water for reflux, adding a chemical mixture with the mass of 0.3-25% of the waste acid under the condition of continuous stirring, heating the mixture to the chemical mixture dissociation reaction temperature and maintaining the chemical mixture dissociation reaction temperature, and continuing heating and stirring for reaction for 1.0-15 hours to enable the chemical mixture to react with aluminum ions to generate corresponding aluminum salts, thereby obtaining reaction liquid for later use;

⑵ preparing seed crystal by pulverizing solid aluminum salt composed of corresponding complexing agent acid radical and aluminum ion and difficult to be dissolved in water and dilute sulfuric acid with stainless steel pulverizer, and sieving the pulverized product with standard sieve to obtain aluminum salt seed crystal;

⑶ seed crystal induction, namely, reducing the temperature of the reaction liquid obtained in the step ⑴ to 0-45 ℃, maintaining the temperature at 0-45 ℃, adding the seed crystal obtained in the step ⑵ with mass fraction capable of playing an induction role into the reaction liquid under the condition of continuous stirring, and continuously stirring for 1.0-25 hours to enable aluminum salt in the seed crystal induction reaction liquid to form aluminum salt precipitate so as to obtain the reaction liquid separated out by the aluminum salt precipitate;

⑷, naturally settling, namely maintaining the temperature of the reaction liquid precipitated by the aluminum salt precipitate obtained in the step ⑶ at 0-40 ℃, controlling the settling and stirring speed, continuing stirring for 5-45 hours, stopping stirring, naturally settling the precipitate for 3-15 hours, and taking the supernatant of the settling for later use;

⑸ membrane separation, namely precisely filtering the supernatant fluid obtained in the step ⑷ by microporous membrane equipment to obtain dealuminizing acid liquor in an aluminum profile anodic oxidation tank for later use;

⑹, analyzing and measuring the mass percent of sulfuric acid of the dealuminizing acid solution of the aluminum profile anodic oxidation tank obtained in the step ⑸, adding concentrated sulfuric acid and a LY-920 wide-temperature oxidizing agent special for aluminum profile anodic oxidation according to the mass percent of sulfuric acid of the aluminum profile anodic oxidation tank acid solution of the aluminum profile anodic oxidation process, and uniformly stirring to obtain the recyclable anodic oxidation tank acid solution for anodic oxidation of the next batch of aluminum profiles.

2. The method for recycling the waste acid from the aluminum profile anodic oxidation tank in the step ⑴ is the residual acid from the aluminum profile anodic oxidation tank used for anodic oxidation of the aluminum profile in the oxidation tank, which has high aluminum ion content, can not be reused and needs to be discarded, and comprises the components of 10-30% by mass of sulfuric acid, 0.8-3.0% by mass of aluminum ions, 0.1-5% by mass of LY-920 wide-temperature oxidant special for anodic oxidation and 68-86% by mass of water, wherein the chemical mixture is one of analytically pure or chemically pure dodecylbenzene sulfonic acid, phytic acid, aluminum profile, phosphoric acid, silicic acid, polysilicic acid, fluosilicic acid and hydrofluoric acid, or a mixture of two to eight of the two or more in any proportion, and the dissociation reaction temperature of the chemical mixture is the temperature capable of promoting the generation of the corresponding aluminum salt and ranges from 15-120 ℃.

3. The method for treating the waste acid from the aluminum profile anodizing tank in the recycling mode according to claim 1, wherein the solid aluminum salt in the step ⑵ is any one of analytically pure or chemically pure aluminum dodecylbenzenesulfonate, aluminum phytate, aluminum oxalate, aluminum phosphate, aluminum silicate, aluminum polysilicate, aluminum fluorosilicate and aluminum hydrofluoride, or a mixture of two or more of the aluminum salts in any proportion, and the screening is 40-600 meshes.

4. The processing method for recycling the waste acid from the aluminum profile chemical polishing tank as claimed in claim 1, wherein the mass fraction capable of inducing the crystallization in the step ⑶ is 0.05-5%.

5. The processing method for recycling the waste acid from the aluminum profile anodic oxidation tank is characterized in that the sedimentation stirring speed in the step ⑷ is the stirring speed at which the aluminum salt can be sedimented, and the range of the stirring speed is 1-50 rpm.

6. The method for recycling waste acid from the anodic oxidation tank of aluminum profile according to claim 1, wherein the microporous membrane device of step ⑸ has a membrane material of silicon carbide, and the membrane component is in the form of honeycomb briquette type inner tubular membrane with membrane pores of 1, 0.5, 0.1 and 0.04 μm.

7. The method for recycling waste acid from the anodic oxidation tank of aluminum profiles as claimed in claim 1, wherein said concentrated sulfuric acid of step ⑹ is sulfuric acid with 98% mass fraction of analytical or chemical purity.

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