Development of a phosphoric acid-based chemical formulation for cleaning low carbon steel that is resistant to the accumulation of iron(III) salts
Year: 2025
Type: article
Abstract: The corrosion of low carbon steel of grade 08PS has been studied in solutions: 1 M H2SO4 + 1 M H3PO4 + Fe(III) salts and 1 M HCl+1 M H3PO4 + Fe(III) salts (60°C) containing three-component mixtures as metal corrosion inhibitors: 2 g/L Inhibitor+0.5 mM KNCS+200 mM HMT (Inhibitor=GREENCOR m.V, INVOL-2 m.A, VNPP-2-V and VNPP-2MV; HMT=hexamethylenetetramine).It has been shown that the lowest corrosion rates of steel (no more than 2.0 g/(m 2 h)) are observed in 1 M HCl+1 M H3PO4 with the inhibitor mixture 2 g/L VNPP-2MV+0.5 mM KNCS+200 mM HMT, even in the presence of Fe(III) salts with concentrations up to 0.10 M. The chemical formulation: 1 M HCl+1 M H3PO4 inhibited with the mixture: 10 g/L VNPP-2MV+0.5 mM KNCS+200 mM HMT, has low corrosivity towards 08PS steel in the temperature range of t =20-80°C with up to 0.10 M Fe(III) salts accumulated in the mixture.The corrosion of 08PS steel in 1 M HCl+1 M H3PO4 (20°C) inhibited by this mixture is characterized by low corrosion rates (up to 1.8 g/(m 2 h)) and weak sensitivity to the convection of the corrosive medium with up to 0.10 M Fe(III) salts accumulated in the medium.Taking the experimental results into account, a chemical formulation based on phosphoric acid for cleaning low carbon steel from mineral contaminants that is resistant to the accumulation of Fe(III) salts is recommended.The formulation contains 1 M HCl+1 M H3PO4 as the acid component.The corrosion inhibitor protecting the steel is a mixture of VNPP-2MV+ 0.5 mM KNCS+200 mM HMT.This chemical formulation can be used both under static and dynamic conditions of metal cleaning.Static solutions can be used at temperatures up to 80°C, inclusive.
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $250
OpenAlex ID: W4411911495