Method for purifying leady oxides

摘要

A process for providing a leady oxide having reduced levels of undesired metallic impurities such as, for example, bismuth and/or silver, comprises roasting the leady oxide to convert part to orthorhombic PbO, exposing the roasted leady oxide to particle size reduction so that the tetragonal PbO can be separated from the orthorhombic PbO fraction, and recovering the orthorhombic fraction having the reduced level of impurities.