Corrosive electrolytes

Abstract

Metals and alloys are extensively used as constructional materials for household and industrial applications. However, most of the metals and their alloys are highly reactive and undergo rapid corrosion depending upon the nature of surrounding environment. The corrosive dissolution is more pronounced in the presence of aqueous electrolytes. Acidic aqueous solutions such as hydrochloric (HCl), sulphuric (H2SO4), nitric (HNO3), phosphoric (H3PO4) and other inorganic or inorganic acid are some common industrially useful corrosive electrolytes. Along with acidic electrolytes, basic and neutral aqueous electrolytes have also been used as corrosive electrolytes. Present report describes the collection of some major corrosive electrolytes and the mechanism of metallic corrosion in such electrolytes. In this report, metallic surface cleaning using acidic solutions of hydrochloric (HCl), phosphoric acid (H3PO4), sulphuric acid (H2SO4), citric acid (C6H8O7), hydrofluoric acid (HF), nitric acid (HNO3), formic acid (HCOOH), acetic acid (CH3COOH), perchloric acid (HClO4) and sulfamic acid (H3NSO3) has been described. More so, corrosion mechanism and surface cleaning using basic solutions such as sodium hydroxide (NaOH), potassium hydroxide (KOH) and ammonium hydroxide (NH4OH) has also been described. Lastly, mechanism of corrosion in NaCl, NaCl saturated with CO2 and CO2 + H2S medium is described in this repost. Mechanism of metallic corrosion in oil, gas and petroleum industrial is also described in this report. This article will help academician and industrialists to find out different aqueous electrolytes being used as metallic surface treatment.