Fluorescent Determination of Trace Calcium in Water from High-Parameter Power Plant Based on a Porphyrin Derivative

摘要

A porphyrin derivative like ortho-methoxyl tetraphenyiporphyrin (o-OCH_3TPP) used as a fluorescent reagent for determination of trace amount of calcium in water from high-parameter power plants has been investigated in this paper. The interaction mechanism was based on complexation of calcium ion and porphyrin with a excitation wavelength of 336 nm and a emission wavelength of 401 nm. The relationship between relative fluorescence intensity of Ca~(2+)-porphyrin complex and logarithm of Ca~(2+) concentration displayed good linear dependence in the range of 1.00 × 10~(-9) mol/L to 1.00 × 10~(-2) mol/L, and the detection limit was evaluated to 4.56 × 10~(-10) mol/L. No significant interferences were observed from alkali metals and alkaline metals, like K~+, Na~+, Li~+, and Mg~(2+). The presented method possessed a nice recovery rate of 97.3~106.5% for determination of trace calcium in water samples from a thermal power plant with very nice reproducibility and stability, indicating that it was a trustworthy and effective means used for the detection of calcium ion in water from high-parameter power plants.