CORROSION INHIBITOR FOR THREE-PHASE SYSTEM Russian patent published in 2006 - IPC C23F11/14 

FIELD: oil and gas production.

SUBSTANCE: invention relates to protection of gas and oil-field equipment and pipelines operated in three-phase highly mineralized media (water, organics, gas) against corrosion and, more specifically, to a method for preparing corrosion inhibitors based on the product of condensation of polypropylene-polyamines with higher isomeric α-ramified monocarboxylic acids or synthetic fatty acids followed by cyanethylation, oxyalkylation, alkylation, and manufacture of preparative form of inhibitor by adding solvent to a certain portion of active base. Polypropylene-polyamines can be a industrial-grade mixture and above-indicated monocarboxylic acids are those with 6-28 carbon atoms while synthetic fatty acids with 10-28 carbon atoms. Condensation is carried out for 4-6 h at 130-160°C while simultaneously distilling off water, after which reaction mixture is heated to 230-250°C for 1.0-2.5 h in inert gas flow. Resulting products are subjected to cyanethylation, oxyalkylation, and alkylation at 35-80°C for 2-4 h. Preparative form of inhibitor is obtained by adding solvent at 250°C, said solvent being product obtained via amination of bottom residue from butyl alcohol production or aminated distillate thereof.

EFFECT: achieved efficient protection of metals against corrosion in hydrogen sulfide-containing three-phase media.

3 cl, 2 tbl, 15 ex