METHOD OF PREPARING ACID CORROSION INHIBITOR Russian patent published in 1998 - IPC

FIELD: corrosion protection. SUBSTANCE: invention relates to protection of metals from corrosion by introducing inhibitors into corrosive medium, in particular, to methods of preparing acid corrosion inhibitors for steel that may be used in petroleum processing, mechanical engineering, power, and chemical industries, etc. to protect steel equipment operated in acid media as well as in composite acid mixtures. Acid corrosion inhibitor is prepared by mixing components including vat residue from santokhin production (8.0-40.0 wt %) and hydrochloric acid (the balance). In preferred methods of inhibitor preparation, formaldehyde-containing compound is added at ratio to inhibitor (0.001-0.3):1. Inhibitors thus obtained are kept to stratification and upper and lower phases are separated. To upper and lower phases with no formaldehyde-containing compound, such compound is added at ratio to both phases (0.001-0.3): 1. To lower phase of inhibitors with or without formaldehyde-containing compound, hydrocarbon solvent is added at ratio of lower phase to hydrocarbon solvent 1:(0.6-1.5). EFFECT: enabled preparation of acid corrosion inhibitor exhibiting high activity in different acid media. 6 cl, 1 tbl, 61 ex