title: Mass spectrometric study of the impurity profile in Zn during reduction-distillation of ZnO with activated and inactivated Al.
abstract: In this work, we report on the application of hyphenated gas source mass spectrometry to study and understand the mechanism of the reduction-distillation of ZnO using Al powder as reductant in its activated and inactivated form. The experiments revealed that the purity of the Zn metal produced were superior using activated Al with respect to inactivated Al, i.e., m5N8 (99.9998% metallic based) versus m5N3. The achieved purity levels of Zn and the absence of high volatile Cd, Mg, and Sb impurities in the gas phase and the material collected were explained with respect to the impurity elements free-energy values, vapor pressure data, and an observed scavenging effect of the Ta crucible, which was supported by the on-line observed mass spectrometric profiles of the residual gas.
authors.affiliation: BAM Federal Institute for Materials Research and Testing Analytical Chemistry and Reference Materials, Richard-Willstätter Strasse 11, 12489, Berlin, Germany.
authors.forename: Anil
authors.initials: A
authors.lastname: Gopala
authors.forename: Michael
authors.initials: M
authors.lastname: Zellmann
authors.forename: Heinrich
authors.initials: H
authors.lastname: Kipphardt
authors.forename: Norbert
authors.initials: N
authors.lastname: Jakubowski
authors.forename: Ulrich
authors.initials: U
authors.lastname: Panne