Purity Determination of High-Purity BeO using Gravimetric Analysis with Stepwise Conversions of Weighing Form of Be

Ensuring accurate and precise measurements of analytes is crucial in gravimetric analysis but can be jeopardized by overlooking analyte in the filtrate, washing solutions, residue during analytical procedure, and weighing form of analyte. To address this issue, a stoichiometric approach for the purity determination of high-purity BeO was developed using gravimetric analysis. This method involved the systematic stoichiometric evaluation of the stepwise conversion of the different weighing forms of Be. The initial BeO sample underwent sequential conversion to the Be complex with N-benzoyl-N-phenyl hydroxylamine, BeO, and BeSO₄; each was evaluated for stoichiometry via gravimetric analysis. The amounts of Be in the filtrate and washing solution, and their loss during sample preparation were measured using inductively coupled plasma-optical emission spectrometry (ICP-OES). Additionally, the sulfate content in the BeSO₄ precipitate was determined by the gravimetric analysis of BaSO₄ to validate the stoichiometry of the precipitate. The observed mass ratios of different Be weighing forms were compared with the theoretical values at each conversion step. The composition of the final converted BeSO_4, i.e., the observed mass ratio of BaSO₄/BeSO₄, was comparable to the theoretical composition. The purity of the initial BeO sample was determined to be 100.03 % ± 0.17 % (k=2). The measured purity was successfully validated by comparing it with that of NIST SRM 3105a Be standard solution using ICP-OES.