Abstract
d was synthesized and its anticorrosive properties were investigated. The corrosion inhibitor was obtained by a one-step synthesis of crude cottonseed oil, diethanolamine, and boric acid (at a molar ratio of 1:3:0.6) in the temperature range of 140–180 °C with continuous distillation of the reaction water. The synthesized viscous cottonseed oil amidoborate was used in experiments without additional purification. The chemical structure of the obtained crude cottonseed oil amidoborate was confirmed by FTIR spectroscopy. Successful nitrogen acylation reaction is confirmed by the appearance of an intense absorption band of the C=O bond of the tertiary amide (Amide-I band) in the region of 1620 cm- ¹. The presence of a donor-acceptor borate center is confirmed by high peaks of the stretching vibrations of the B–O–C ether bonds in the region of 1047–1050 cm- ¹. The high protective effect is explained by the strong chemisorption of the polar "head" of the molecule (electron pairs of nitrogen and boron) on the metal surface, forming a dense hydrophobic layer of hydrocarbon "tails" of cottonseed oil. The anticorrosive efficacy of an amidoborate corrosion inhibitor obtained from crude cottonseed oil was studied gravimetrically. Due to the availability of raw materials and high biodegradability, the developed amidoborate complex based on crude cottonseed oil holds great promise for protecting drilling equipment. The obtained results open up broad opportunities for the introduction of import-substituting, biodegradable, and cost-effective oleochemical corrosion inhibitors into oil and gas well drilling practices in complex mining and geological conditions.