Abstract
A new simple techique for the microdetermination of fluorine in the presence of aluminum was obtained by using the fluoride ion electrode. Procedures are as follows ;
Aluminum fluoride complexes were deeomosed in alkali (pH>12) and the liberated aluminum was masked with oxine. The pH and total ionic strength were adjusted with TISAB, and fluorine determination was carried out with no extraction of the aluminum-oxine complex and free oxine.
The calibration curve showed a linearity down to less than 0.1 ppm (5.3×1O-6M) of fluorine in the presence of 4 ppm of aluminum and oxine, which is as good as measurements obtained in the absence of aluminum.
Recovery of 1 ppm of fluorine was relatively good-about 95%-, even in the presence of 200 ppm of aluminum. Good recovery of fluorine added to artificial cryolite was also found.
