催化动力学光度法测定锅炉给水中异抗坏血酸钠

CATALYTIC KINETIC PHOTOMETRIC DETERMINATION OF SODIUM ISOASCORBATE IN BOILER FEED WATER

基于催化动力学过程 ,研究了新型锅炉给水除氧剂异抗坏血酸钠的分光光度法测定。试验表明 ,这一方法操作简便、快速、准确度高 ,可测至 5 μg·L-

Based on the activation effect of isoascorbic acid on the Landolt reaction between KBrO 3 and rhodamine B catalyzed by vanadium(Ⅴ), a simple method for the kinetic determination of sodium isoascorbate which is used as a new deoxidant in boiler feed water is proposed. Linear relationship between the values of lg( A 0/A ) and the concentrations of sodium isoascorbate is obtained in the range of (0.2～8.0μg)/40ml. The linear regression equation is found to be: lg( A 0/A )=-2.8034×10 -3 +0.88203 where A 0 is the absorbance of the unactivated solution, A is the absorbance of the activated solution, is the concentration of sodium isoascorbate (μg/40ml) (The absorbances are measured at 555nm with 1cm absorption cell.) The correlation coefficient is found to be 0 9969, and the average RSD is 2.1% ( n =15, =0.1μg·ml -1 ). As low as 5μg·L -1 of sodium isoascorbate can be accurately determined by this method.