INHIBITION METHOD OF CARBON-DIOXIDE STEEL CORROSION Russian patent published in 2010 - IPC C23F11/04 

FIELD: metallurgy.

SUBSTANCE: method involves introduction of inhibitor to corrosive medium contacting with steel surface in concentration of 0.25-5.0 mg/l; at that, as inhibitor there used is ammonium salt of O,O-dialkylthiophosphoric acid of formula (RO)₂P(S)SH·A, where at R=i-C₈H₁₇O A=(C₂H₅)₃N, at R=i-C₄H₉₀ A=(CH₃)₂NC_12-14H_25-29, at R=C_12-14H_25-29O A=(C₂H₅)₃N, at R=i-C₈H₁₇O A=(CH₃)₂NC_12-14H_25-29, at R=i-C₄H₉O A=C₁₂H₂₅N₂H₂, or mixture in ratio of 3:1 of ammonium salts of O,O-dialkylthiophosphoric acids: (i-C₄H₉O)₂P(S)SH·C₁₂H₂₅NH₂ and (i-C₈H₁₇O)₂P(S)SH·C₁₂H₂₅NH₂.

EFFECT: method allows obtaining protective effect at using low concentrations of inhibitor and increasing inhibition efficiency in wide temperature range.

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