PRODUCTION OF CARBON DIOXIDE CORROSION INHIBITORS OF STEEL FROM DIAMINES AND TALL OIL FATTY ACIDS

Substituted imidazolines are one of the most common and effective surface-acting metal corrosion inhibitors. The main tasks of today are to reduce their cost and increase their hydrolytic stability, which is achieved through a targeted choice of the nature and structure of long-chain carboxylic acids in the synthesis of imidazolines. Another way to reduce the cost of producing corrosion inhibitors based on aliphatic ethylenediamines is to use imidazoline precursors – amidoamines and ammonium salts - to protect against corrosion, the production of which is much less energy-consuming.The synthesis of active substances of carbon steel corrosion inhibitors in the reaction of diamines with fatty acids of tall oil was carried out. It is shown that depending on the temperature of the reaction and the introduction of the catalyst – polycationite CU-2-8 - it is possible to selectively obtain derivatives of imidazolines, amidoamines, and ammonium salts, which are capable of inhibiting carbon dioxide corrosion of steel in mineralized water at 60 °C with a degree of protection from 85 % to 91 %. It is noted that the protective effect of amidoamines and ammonium salts is practically not inferior to the action of imidazolines.