日本語
한국어
Français
Deutsch
Español
Italiano
Português
Việt Nam
Türkçe
عربي 
русский 
Čeština
ไทย
Eesti
Gaeilgenah Éireann
Bai Miaowen
íslenska
Cymraeg
Български
اردو
Polski
hrvatski
українська
bosanski
فارسی
Lietuvių
Latviešu
עברית
România limbi
Ελληνικά
dansk
magyar
Norsk
suomi
Nederlands
Svenska
slovenčina
slovenščina
हिंदी
Indonesia
Melayu
Malti
Kreyòl Ayisyen
Català
বাংলা
Srbija jezik (latinica)
O'zbek
The causes of corrosion inside the pipeline.
Oxidation theory (Acid.theory)
Due to the carbonic acid (H2CO3) in water, iron becomes ferrous carbonate, which is then oxidized by oxygen in water to become iron hydroxide.
Peroxide theory
Iron is first combined with hydration to synthesize ferrous hydroxide, then the hydrogen produced is oxidized with water to produce H2O2, and then ferrous hydroxide and H2O2 are combined to produce iron hydroxide.
- Fe+H2O→Fe(OH)2+H2↑
- H2+O2→H2O2
- 2Fe(OH)2+H2O2→2Fe(OH)3(Rust)
Electrochemical theory
Corrosion is caused by an electrochemical reaction, the first is formed ferrous hydroxide, in alkaline water, with oxidation and formation of iron hydroxide, forming a film and remaining on the metal surface. In acidic water, it first forms CO2 with carbonic acid in water to form ferrous bicarbonate Fe(HCO3)2, and then oxidizes with water to synthesize iron hydroxide, which is precipitated from water by plankton formation.
