CORROSION INHIBITOR FOR ANTIFREEZES Russian patent published in 1999 - IPC

FIELD: chemical technology, cooling systems in internal combustion engines, and heat exchangers. SUBSTANCE: corrosion inhibitor comprises, wt.-%: 0.88-% orthophosphoric acid, 2.0-25.0; potassium hydroxide, 2.0-25.0; disodium salt of dihydrate ethylenediamine tetraacetic acid, 0.1-1.0; sodium carbonate, 0.1-2.0; foam suppressor, 0.01-1.0; colorant, 0.01-0.5; water, 10.0-30.0; non-ferrous metal inhibitor, 0.1-44.0; and ethylene glycol or polyglycols, the balance. Non-ferrous metal corrosion inhibitor comprises, in terms of whole inhibitor, wt.-%: sodium metaphosphate, 0.2-2.0; or caprolactam, 0.1-2.0; or carbamide, 0.5-5.0; or benzotriazole, 0.5-5.0; or atmospheric corrosion inhibitor, 0.1-5.0; or sodium benzoate, 0.5-25.0; or mixture thereof in any combination. Sodium metaphosphate is sodium hexametaphosphate or polyphosphate. The corrosion inhibitor has higher activity and increases alkalinity. EFFECT: improved properties of the corrosion inhibitor. 3 cl, 4 tbl