COLORIMETRIC METHOD OF DETERMINATION OF PRESENCE OF IRON IN MOTOR PETROL Russian patent published in 2005 - IPC

FIELD: methods of analysis of materials, motor petrols in particular.

SUBSTANCE: proposed method includes drawing sample, conversion of iron into liquid phase, addition of 1-2 drops of potassium ferricyanide (III) indicator at concentration of 5-10 mass-% followed by estimation of presence of iron by change of tint of aqueous phase; conversion of iron into aqueous phase is carried out by addition of oxidant solution to sample at ratio of 1:10-15; solution is prepared by mixing 11.25 g of potassium iodide, 7.5 g of potassium iodate, 45 ml of concentrated hydrochloric acid and diluting with distilled water to 200 cm³; then solution is mixed for 1-3 min and distilled water is added at ratio of 4:1 relative to oxidant solution volume; indicative of presence of iron is change in tint of aqueous phase after addition of indicator from yellow-green to blue-green.

EFFECT: enhanced reliability of determination.

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