Rust removing and preventing agent

Abstract

A rust removing and preventing agent comprises, by mass, 1-60 parts of phosphoric acid, 1-10 parts of phosphate, 0.5-5 parts of a complexing agent, 0.5-5 parts of corrosion inhibitor, 0.5-5 parts of a surface active agent and 5-80 parts of deionized water. Hydrogen ions provided by phosphoric acid of the rust removing and preventing agent can react with rust stains on the surface of steel so that the solid rust stains can be dissolved. By means of adding of phosphate, the concentration of HPO42- and H2PO4- in the rust removing and preventing agent can be improved, accordingly, ionization equilibrium of the phosphoric acid moves leftwards, and therefore the content of free acid in a solution is reduced; and the rust removing process becomes slower and more durable, and the situation that rust in a rust stain area with the high rusting degree on the surface of the steel is not removed thoroughly while an iron material area with the low rusting degree directly reacts with the hydrogen ions is avoided. After rust removing is finished through the rust removing and preventing agent, a dense phosphating film can be formed on the surface of steel.

Description

technical field [0001] The invention relates to the technical field of rust removal and antirust, in particular to a rust removal and antirust agent. Background technique [0002] At present, in the iron and steel manufacturing industry, it is generally necessary to perform derusting treatment on the surface of the steel to ensure that high-quality steel products are manufactured. [0003] In the existing iron and steel derusting agents, hydrochloric acid, sulfuric acid and hydrofluoric acid are usually used as the main components, and the main disadvantages thereof are: on the one hand, the iron and steel derusting agents will volatilize into the air during the derusting operation. A large amount of acid mist is produced, which seriously endangers the health of the human body; on the other hand, a large amount of chloride ions and fluorine ions are produced, which will cause environmental pollution when they are discharged or leaked to the outside world. [0004] In additi...

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Problems solved by technology

[0003] In the existing iron and steel derusting agents, hydrochloric acid, sulfuric acid and hydrofluoric acid are usually used as the main components, and the main disadvantages thereof are: on the one hand, the iron and steel derusting agents will volatilize into the air during the derusting operation. A large amount of acid mist is produced, which seriously endangers the health of the human body; on the other hand, a large amount of chloride ions and fluorine ions will be produced, which will cause environmental pollution when they are discharged or

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