The estimation of boron in boronised metals

Abstract

The more general methods for the separation of boron from associated elements, and for its estimation, are briefly considered.Work carried out in adapting Tschischewski's method to the estimation of boron in boronised iron, nickel, cobalt and copper is described, in which these metals are removed by mercury cathode electrolysis. In addition, a rapid method for the estimation of boron in boronised molybdenum is described in which the metal is separated as the sulphide. The boron after conversion to mannitoboric acid is finally determined by potentiometric titration with sodium hydroxide, which obviates the difficulties inherent in the use of colour-change indicators.The methods as described have an accuracy of about 1.4 per cent. of the amount of boron present over the range 0.27 to 4.30 per cent., which may be extended with slight modification.

Ferrous Metallurgy

“…All of the beryllium was recovered in the first and second effluent and it was found to be spectrographically free from aluminum. BORON Bush and Higgs (37) found the mercury cathode cell satisfactory for removing such elements as iron, nickel, cobalt, and copper from boron prior to its determination in metal-boron alloys. The boron was then titrated potentiometrically in the presence of mannitol with standard sodium hydroxide.…”

Determination of Boron and Carbon in Alkyldecaboranes and Related Compounds

“…To standardize the titrant, carbonate-free O.IOjV baryta, dissolve 0.15 gram of dry, recrystallized boric acid and 7 grams of mannitol in 100 ml. of distilled water and titrate the solution potentiometrically to a pH end point (about 8.4) (4). Titrate a blank solution of mannitol and water to pH 8.…”