Electrochemical process for preparation of Zinc powder

摘要

Disclosed is an electrochemical process for preparing zinc powder which involves: a) providing to an electrochemical cell a basic solution or suspension of zinc oxide or any other zinc compound that reacts with an aqueous base to produce zinc oxide. The basic solution or suspension is prepared by dissolving the zinc oxide or the other zinc compound in an aqueous 1.25 to 10.0 M base solution, containing at least 2 millimoles of solubilized zinc based species per 100 grams of electrolyte; and b) passing current to the cell at a current density of about 500 to about 40,000 A/m<2> for a time period sufficient to electrochemically reduce the zinc oxide to zinc powder, wherein the electrochemical process has a current efficiency of at least 70% and is substantially free from electrode corrosion. In one of its aspects the invention further provides for a continous process, wherein a sufficient amount of the zinc oxide or the other zinc compound is added continuously or intermittently to the cell to maintain the concentration of the solubilized zinc based species at a level of at least 2 millimoles per 100 grams of electrolyte and at least a portion of the zinc powder formed is removed continuously or intermittently.