QUANTITATIVE ANALYSIS OF THIOUREA AND SODIUM FLUORESCEIN SIMULTANEOUSLY PRESENT IN FORMATION WATER Russian patent published in 2013 - IPC G01N21/17 

FIELD: chemistry.

SUBSTANCE: quantitative analysis wherein an analysed sample is separated from oil; cleaned from mechanical impurities; clarified in a centrifuge; alkali is added for quantitative determination of sodium fluorescein using a luminescent technique; and concentration of thiourea and sodium fluorescein is determined by an interpolation technique from results of three combined measurements, one of which is associated with the sample and the other two are associated with model solutions prepared from the analysed sample by fixed dilution with formation water and fixed addition of the analysed indicator in such an amount that the signal of one of the model solutions is greater, and for the other - less than the signal of the analysed sample. To analyse thiourea, a fixed amount of sodium pentacyano-aqua-ferrite and sodium fluorescein in an amount equal to the amount in the sample which is measured by a luminescent technique are added to the analysed sample.

EFFECT: high accuracy of measuring concentration of thiourea and sodium fluorescein.

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