Cr-doped titanite pigment based on industrial rejects

authors	Hajjaji, W; Zanelli, C; Seabra, MP; Dondi, M; Labrincha, JA
nationality	International
journal	CHEMICAL ENGINEERING JOURNAL
author keywords	Chromium doping; Titanite; Ceramic pigment; Marble sawing sludge; Galvanizing waste; Foundry sand
keywords	MALAYAITE CERAMIC PIGMENTS; TECHNOLOGICAL PROPERTIES; OPTICAL SPECTROSCOPY; CRYSTAL-CHEMISTRY; OXIDATION-STATES; PHASE-TRANSITION; IONS; LUMINESCENCE; CASSITERITE; CATIOSIO4
abstract	This work reports the development of inorganic pigments based on chromium doped titanite (CaTiSiO(5)). For economical and environmental reasons, wastes were used as raw materials but similar formulations from pure reagents were also prepared to assess the effect of impurities contained in wastes. Pigments were characterised by XRD, SEM + EDS microprobe analysis, and UV-vis-NIR spectroscopy. The colouring mechanism (the pigment is reddish brown) seems to result from the combined contribution of octahedral Cr(III) and tetrahedral Cr(IV)species replacing Ti(4+) and Si(4+), respectively. In both pure reagents and waste-based pigments, colorimetric parameters were evaluated and their colouring performance was tested in transparent and opaque ceramic glazes. Intense and stable brown hues were developed with optimized formulations, i.e. containing 0.044Cr at 1300 degrees C. (C) 2009 Elsevier B.V. All rights reserved.
publisher	ELSEVIER SCIENCE SA
issn	1385-8947
year published	2010
volume	158
issue	2
beginning page	167
ending page	172
digital object identifier (doi)	10.1016/j.cej.2009.12.026
web of science category	Engineering, Environmental; Engineering, Chemical
subject category	Engineering
unique article identifier	WOS:000276737400011