The purpose of the present investigation was to develop a quick and simple method for the determination of beryllium in bcryl, gcncrally associated with the minerals of pcgmatitc origin.
Beryllium is usually dctcrmined tither by gravimetric or photometric methods. In the gravimctric methods it is cstimatcd either as oxidc1~2~3A5 or as phosphatc0. Particular mention may bc made of the phosphate method, wherein beryllium is prccipitntcd as beryllium ammonium phosphate and ignited and wcighcd as Be,I',O,, interfering clcmcnts being kept in solution with complcxone II. The photometric methods make USC of either the colour reactions or fluorescence of Be'2 with organic reagents7,a~o~lU,l'r'g,l3,14,16,10, While them has been considerable dcvelopmcnt, particularly in the latter field, the analytical chemistry of beryllium is conspicuous by the absence of a good volumetric proccdurc. The only one reported so far is based on the following reactions". 13eryllium, prccipitatcd quantitatively as Bc(0 Z-Q at per 8.5, when treated with an alkali fluoride, liberates two equivalents of alkali which may be titrated aciclimetrically.
Evidently, a host of other ei.zments, react similarly, so that all of them must either be absent, or their concentrations accurately known in order that suitable cbrrections may bc applied. Even when such corrections are possible, the method is csscntially empirical, the reaction between Be(OH), and fluoride not being stoichiometric'0.
The prcscnt paper describes a volumetric method in which beryllium is precipitated under suitable conditions as beryllium ammonium phosphate, and determined indirectly by titrating its equivalent phosphate against standard bismuthyl pcrchloratc. hf ETHOD The mctllod consists essentially of two steps: I. Yrecip.tation of beryllium as berylliurn ammonium phssphate. The method Rcfewnccs p. II/IZ M. SANXAR DAS, V. T. ATHAVALT: VOL.