Universal environment-friendly ash removal agent for aluminum and aluminum alloy

Abstract

The invention discloses a universal environment-friendly ash removal agent for aluminum and aluminum alloy. The universal environment-friendly ash removal agent comprises 0.01-5.0 g / L of rare earth metal salt, 5-100 g / L of an oxidizing agent, 5-100 g / L of an acid agent, 0.1-5 g / L of a corrosion inhibitor, 0.1-10 g / L of a chelating agent, 0.1-10 g / L of a stabilizer, 0.01-5 g / L of a surfactant, and the balance of water. Compared with the prior art, the ash removal agent has the characteristics of normal-temperature operation, high ash removal speed, capability of meeting the ash removal requirements of various aluminum alloy materials, no generation of corrosive gas and no pollution to the water environment, and can achieve nearly zero emission in cooperation with an environment-friendly ash removal process.

Description

Technical field [0001] The present invention relates to the field of aluminum and its alloy surface treatment, and is specifically a general-purpose aluminum and alloy environmental deprive agents. Background technique [0002] Aluminum and its alloy density, high intensity, plasticity and machining, excellent conductive, thermal conductivity, electromagnetic shielding, damping resistance, etc., in construction, communication, home appliances, machining, aviation, aerospace, automotive, machinery manufacturing , There is a wide range of applications in the fields of ships and chemical industries, which becomes a metal material that is the most used in non-ferrous metals. [0003] Since aluminum is a active metal, aluminum and its aluminum alloy surfaces are easily oxygen in the air, and the water gas reaction is rapidly oxidized to form a layer of oxide film. This layer of oxide film has a certain corrosion resistance, but since it is amorphous, the surface of the aluminum is los...

AI Technical Summary

Problems solved by technology

[0005] At present, the existing ash removal processes are sulfuric acid, nitric acid, hydrofluoric acid, chromic acid, etc. and their mixed acid ash removal methods. Among them, the most commonly used and most widely used method is the nitric acid ash removal method. Its main disadvantages are: the concentration of the bath solution High, large amount of acid, large pollution, short life, difficult maintenance of bath solution, and for alloy aluminum materials containing manganese, iron, copper, especially silicon, the speed of ash removal is slow or even powerless, which will cause aluminum substrates corrosion, snowflake-like corrosion spots appear on the surface of the material

Nitrogen oxides and acid droplets released due to the decomposition of nitric acid in the process of nitric acid deashing are more harmful

And the ammonia nitrogen in the ash removal waste liquid is also a potential problem in the ash removal waste liquid treatment

The deashing agent described in Chinese patent CN105316691 is composed of 130-200g / L nitric acid, 20-40g / L sulfuric acid, potassium permanganate, sodium fluoride and glacial acetic acid, which contains a large amount of nitric acid, which will inevitably produce Nitrogen oxides, the air environment in the workplace is harsh; the treatment liquid contains nitro, manganese ions, and fluorine ions, which are difficult to meet the standards and endanger the environment

The deashing agent described in Chinese patent CN109518200 contains ferrate, which is difficult to exist stably in an acidic solution and has a strong oxidizing property. The electrode potential is as high as 2.2V, and the new ecological atomic oxygen generated in the aqueous solution can dissociate it The organic corrosion inhibitor is oxidized to carbon dioxide, so this working fluid will change quickly after preparation and become invalid

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