SYNTHESIS, CHARACTERIZATION AND EVALUATION OF COBALT BASED GREEN COLORED PIGMENT AS ECO-FRIENDLY ALTERNATIVE

Abstract

The present work describes the synthesis of environment friendly green colored inorganic pigment, from cobalt oxide with zinc oxide. These pigments have been synthesized by the incorporation of cobalt admixtures in zinc oxide in varying amounts. They are of special interest as they provide an alternative to replace toxic chromates in anticorrosive coating formulations. Their intense green color, hues, lower cobalt content, and thermal stability also provides additional advantages. Synthetic chemistry of such pigments is based on the non-stoichiometric interaction of the crystal lattices of both zinc oxide (ZnO) and cobalt oxide (CoO). Various pigments were prepared using various stoichiometric ratios of cobalt and zinc oxide. The prepared pigments were incorporated in the epoxy matrix and tested for their anticorrosive performance and found satisfactory in comparison to the chromium (III) based pigment having toxicity and environmental constrains.