PREPARATION OF TREATMENT COMPOSITION AND BATH MAINTENANCE SYSTEM AND METHOD FOR TREATMENT FORMED THEREFROM Russian patent published in 2020 - IPC C23C22/48 C01D15/08 

FIELD: chemistry.

SUBSTANCE: invention relates to processing compositions intended for forming a protective coating on the surface of substrates, as well as to preparation of such compositions and to methods for maintaining baths for treatment formed from said treatment compositions. Method of producing a treatment composition for forming a protective coating on a substrate containing lithium carbonate involves a reaction of lithium cation and a carbon dioxide source in an aqueous medium to obtain a treatment composition. Said treatment composition contains lithium cation in amount of 5 ppm to 5,500 ppm, with respect to lithium cation, based on total weight of treatment composition, and an anion of carbonate in amount of 15 ppm to 25,000 ppm, based on the anion of carbonate, based on the total weight of the treatment composition. Substrate treated with the composition obtained by said method. Method of preparing a bath for forming a protective coating on a substrate containing said treatment composition comprises feeding into the bath during and/or after treatment of the substrate in said bath of at least one of a carbon dioxide source and a lithium source in an amount sufficient to maintain the pH of the treatment composition from 9.5 to 12.5. Substrate treated in a bath containing a composition containing lithium carbonate to form a protective coating, wherein said bath is prepared using said method.

EFFECT: providing treatment compositions which are environmentally safe and harmless to health, which can be obtained in a cost-effective manner from readily available resources, and can form a protective layer, which provides effective protection against corrosion and having a suitable adhesion on the surface of the substrate, comparable to compositions containing phosphates and/or chromates.

16 cl, 3 dwg, 6 tbl, 13 ex