Compound corrosion inhibitor for corrosion medium and preparation method thereof

Abstract

The invention provides a compound corrosion inhibitor for a corrosion medium. The compound consists of the following components in percentage by mass: 10 to 75 percent of maleated maleic anhydride, 10 to 75 percent of oleamide corrosion inhibitor, 10 to 75 percent of sodium molybdate corrosion inhibitor, and 5 to 50 percent of benzotriazole (BTA) corrosion inhibitor. The compound corrosion inhibitor for the corrosion medium is particularly suitable for a neutral and alkaline corrosion medium, and can simultaneously and effectively inhibit the corrosion of carbon steel and copper alloy in the neutral and alkaline medium. The method for preparing the compound corrosion inhibitor is simple, and the synergy effect ensures that dosage of each corrosion inhibitor in the compound corrosion inhibitor is remarkably reduced compared with that of single use of the corrosion inhibitor, so that the production cost is lower; and the compound corrosion inhibitor is an environmentally friendly corrosion inhibitor, so that normal operation of the equipment cannot be influenced.

Description

technical field [0001] The invention belongs to the field of metal corrosion and protection, and in particular relates to a composite corrosion inhibitor suitable for corrosive media and a preparation method thereof. Background technique [0002] Corrosion inhibitors are substances that are added to corrosive media to significantly reduce the corrosion rate of metals. Because of their small dosage (a few parts per million to a few parts per thousand), low prices, wide sources, good effects, and strong versatility, It occupies an important position in various metal protection methods (see reference (1): Li Xianghong, Qu Qing, Jiang Shuan, etc. The adsorption of rare earth ions and ligands on steel and aluminum surfaces and their synergistic mechanism of corrosion inhibition. Chinese Science Foundation , 2006, 2:99-103). Corrosion inhibitors can be divided into inorganic and organic according to their chemical composition. Inorganic corrosion inhibitors are oxides that promo...

AI Technical Summary

Problems solved by technology

Molybdate has corrosion inhibition effect on copper and copper alloys, its toxicity is extremely low, and it has little environmental pollution. It is a promising inorganic salt environment-friendly corrosion inhibitor, but its cost is relatively high

The toxicity of tungstate is very low, there is almost no harm to the environment and human body, and it does not cause microbial growth. It is an environmentally friendly corrosion inhibitor. However, the single use of tungstate has low corrosion inhibition efficiency for copper, large dosage and high cost.

Thiourea and its derivatives are mainly thiourea and di-o-toluenethiourea, which have good water solubility and a certain ability to complex copper ions, but the effect of single use is not ideal.

Commonly used azole corrosion inhibitors are mercaptobenzothiazole, benzotriazole (BTA), tolyltriazole, hydroxybenzimidazole, etc. Among them, mercaptobenzothiazole is carcinogenic and has been banned; Copper has good corrosion inhibition, but it is slightly soluble in water, and the resulting film is very thin. If there are corrosion products or scale deposits on the metal surface, it is difficult to form a good corrosion inhibition film.

Images