CHI Zhixian
(Quanzhou Arts and Crafts Vocational College, Quanzhou 362500, Fujian, China)

Abstract: The brown ceramic pigments with spinel structure were prepared by using Cr-rich tanning sludge. The washed Cr-rich leather sludge was calcined at high temperature (1100 ℃) for 1 h with nitrogen as protective gas and its residue was used as chromium oxide precursor (named as GY). The brown ceramic pigments were synthesized by solid phase sintering, and the effects of GY addition amount and calcination temperatures on the properties of the pigments were explored. The crystalline phases of the obtained pigments were characterized by XRD. Furthermore, the morphology as well as the composition of the pigments was investigated by scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS). The color effects of the pigments and the glaze surface were characterized by chromascope. The results showed that the obtained pigments sintered at 1150 ℃ with 50wt.% GY possessed good crystallinity, uniform particle size distribution, small dimension and excellent color effect.

Key words: tanning sludge; chromic oxide; brown pigments; spinel structure