Preparation and coloring mechanism of cobalt-free black ceramic pigments from stainless steelmaking dust

Abstract

In order to improve the recovery of Fe, Cr, Mn and Ni in stainless steel dust and efficiently recycle of stainless steel dust, this study supplies a novel method for the development of high-quality, low-cost and environmentally friendly cobalt-free black ceramic pigments. The results show that the optimal parameters for preparing the cobalt-free black ceramic pigments from stainless steelmaking dust are Fe/Cr/Mn/Ni molar ratio of 1:1:1:1 in the mixture of stainless steelmaking dust and chemical reagents, sintering temperature and holding time of 1125 °C and 30 min respectively, and cooling in the furnace to room temperature. Under this condition, the material undergoes high-temperature sintering reaction to produce Fe 3 O 4 , FeCr 2 O 4 and NiFe 2 O 4 , which results in the black color of prepared pigment. Meanwhile, the prepared pigments have uniform and superior coloring properties ( L* = +36.43, a* = +2.61, b*= +1.70 and C *= +3.11), which are better than those of commercial cobalt pigments.