COMPOSITE FOR EXPRESS-TESTING NITRATE ION BY METHOD OF DROP-VISUAL COLORIMETRIC ANALYSIS Russian patent published in 2003 - IPC

FIELD: analytical chemistry. SUBSTANCE: invention relates to composites used for determination of nitrate ions. Composite comprises the following components, wt. %: silica gel containing 3 wt.% of para-nitroaniline, 1.5; silica gel containing 1 wt.% of chromotropic acid disodium salt, 1; silica gel containing 10 wt.% of racemic acid, 26; silica gel containing 5 wt.% of potassium hydrocarbonate, 2.7; powder-like zinc, 0.4; anhydrous sucrose, up to 100% of total mixture mass. Invention provides to expand the range of nitrate ions concentration to be determined, reduce sample volume and time of analysis. EFFECT: improved method of analysis, valuable properties of composite. 2 tbl, 1 ex