Transactions of the INDIAN CERAMIC SOCIETY Vol. 46 1987
A Rapid Method for Accurate Determination of Boron
in Glass, Enamel and other Silicate Materials
B. MITRA AND B. C. SINHA
Pages : 132-135
DOI : 10.1080/0371750X.1987.10822854
Abstract
A simple and rapid method has been worked out for accurate determination
of boron in commercial glasses, enamels and other silicate
materials by alkalimetric titration of boron as mannitoboric acid. In
the method, the error due to the loss of boron during decomposition
of a sample at high temperature by fusion with Na2C03 in existing
methods has been eliminated by fusing at low temperature with NaOH.
Bromothymol blue has been advantageously used as the indicator at
pH 6.5 (pale yellow to bluish green) for neutralization of free acids
and titration of mannitoboric acid. The interference of phosphate
has been successfully eliminated by precipitating it out as zirconyl
monohydrogen phosphate. Fluorine, calcium and magnesium up to
50 mg per 50 ml did not interfere.
