Kinetic Fluorimetric Determination of Formaldehyde by Oxidation of Rhodamine B with Potassium Bromate

Abstract

Based on the H2SO4-Rhodamine B-KBrO3 system, the kinetic fluorescence method was used to determine formaldehyde. The experimental results show that in the sulfuric acid medium, the fading process of oxidized rhodamine B by potassium bromate is inhibited by the catalytic action of formaldehyde. The results showed that the formaldehyde concentration in the range of 0.4 to 4.4 μmol/L had a good linear relationship with lg (IF/I0F) = 0.01385 c (μmol/L) + 0.02353, the correlation coefficient was 0.9974, and the method detection limit was 0.3027 μmol/L. In the determination of formaldehyde in the synthetical water sample and laundry water, the recoveries were 98.68% and 103.20%. The results were consistent with the certified value.