METHOD OF PREPARING SOLUTION FOR ZINC NITRATE/PHOSPHATE CONCENTRATE Russian patent published in 1998 - IPC

FIELD: corrosion protection. SUBSTANCE: invention relates to producing phosphatation concentrates used for applying phosphate layer before dyeing and varnishing operations and also as independent metal corrosion-protection means. Invention is distinguished by that, when using zinc metal as zinc-containing raw material, solution for producing zinc nitrate/phosphate concentrate is prepared as follows. 30-50% phosphoric acid is first prepared and then is fed onto zinc metal to induce reaction proceeding with heating of reaction mixture to 90-180 C. Resulting mixture with density 1.41-1.82 g/cu. cm is added to nitric acid and dissolution of zinc is repeatedly performed. EFFECT: extended raw material resource for phosphatation concentrate production, reduced loss of zinc, and increased productivity and economical efficiency of process. 2 cl, 1 dwg, 1 tbl