Determination of boron in nickel-base alloys by the dianthrimide method.
The dianthrimide method for the determination of boron in iron and low-alloy steels may be applied to nickel-base materials. The sample is dissolved, without any loss of boron, by hydrochloric and sulphuric acids and the resulting boric acid determined spectrophotometrically with dianthrimide. Background corrections are necessary to compensate for the absorbance from ions such as nickel and iron.
The effect of foreign ions on the spectrophotometric determination of boron with 1,1'-dianthrimide
Abstract The effects of about 40 inorganic ions and reducing and oxidizing agents on the determination of boron with 1,1'-dianthrimide were studied spectrophotometrically. The separate foreign ions were added both to solutions containing boron and 1,1'-dianthrimide and to solutions containing only 1,1'-dianthrimide. From the two series of extinction measurements conclusions were drawn as to the type of interference present. With the use of hydrazine sulphate as reducing agent, the only ions interfering were: germanium (IV), tellurium(IV), cobalt(II), nickel(II), copper(II), chromium-(III), bromide, iodide, fluoride, vanadate and high concentrations of orthophosphate. A new method of indicating spectrophotometric interference was introduced.
A study of the conditions for the determination of boron with dianthrimide
Abstract The reaction between boric acid and dianthrimide in concentrated sulphuric acid has been studied from an analytical point of view using a statistically planned experimental design. Certain interactions between the different factors affecting the reaction that have not previously been taken into account were found to be significant. Thus, the reaction rate is affected by both the acid and the dianthrimide concentrations. The temperature at which the reaction is carried out affects the absorbance less at higher acid concentrations. Suitable analytical conditions are described.