Recycling of solid wastes in the synthesis of Co-bearing calcium hexaluminate pigment

authors	Hajjaji, W; Seabra, MP; Labrincha, JA
nationality	International
journal	DYES AND PIGMENTS
author keywords	Calcium hexaluminate; Cobalt; Blue pigment; Wastes
keywords	CERAMIC PIGMENTS; GLASS-CERAMICS; HIBONITE; MAGNETOPLUMBITE
abstract	Cobalt doped calcium hexaluminate was firstly synthesized using pure reagents; subsequently, the pure reagents were substituted with industrial wastes, the composition of which had been characterized using X-Ray diffraction and X-Ray fluorescence namely, Al-anodising sludge replaced pure aluminium whilst marble cutting rejects and foundry sand were employed as sources of calcite and silica, respectively. As expected, cobalt doped hibonite was the major phase present in calcined powders and displayed an intense blue coloration due to the incorporation of cobalt in tetrahedral positions, as confirmed by transitions from (4)A(2)(F) to the excited (4)T(1)(F) and (4)T(1)(P) states observed from UV-Vis-NIR absorption spectra. The novel waste-derived hibonite pigment showed strong and stable colouring potential when applied in different ceramic supports. (C) 2009 Elsevier Ltd. All rights reserved.
publisher	ELSEVIER SCI LTD
issn	0143-7208
year published	2009
volume	83
issue	3
beginning page	385
ending page	390
digital object identifier (doi)	10.1016/j.dyepig.2009.06.004
web of science category	Chemistry, Applied; Engineering, Chemical; Materials Science, Textiles
subject category	Chemistry; Engineering; Materials Science
unique article identifier	WOS:000269280500018