Determination of zinc oxide in zinc powder by X-ray powder diffractometry

Abstract

An X-ray diffractometric method is applied to determine zinc oxide with low crystallinity in zinc powder. Zinc oxide prepared by thermal decomposition of zinc oxalate exhibited more approximate attice distortion (β cot θ) of the zinc oxide in samples than pulverized one due to lower crystallinity. Therefore, thermally decomposed zinc oxide was employed as a standard material. To reduce errors due to the difference in crystallinity between the standard material and samples, the synthesized zinc oxide was heated to such an extent that its half-width of 002 reflection line was equal to that of zinc oxide contained in samples. The standard mixture for calibration was prepared as follows: a known quantity of the standard zinc oxide {(1~10)%} was added to an aliquot of the sample, and they were mixed by hand in an agate mortar. A straight line was obtained over the range of (1~10)% additives by measuring the 002 reflection line intensity of zinc oxide. The present standard addition method was applied to the determination of zinc oxide of (1.9~5.9)% in zinc powder. The determination limit was 0.27%, and 5.8% of the coefficient of variation was obtained by ten measurements at a level of 3.9% zinc oxide content. © 1980, The Japan Society for Analytical Chemistry. All rights reserved.