abstract
Electroplating sludge (ES) is currently disposed in landfills and, because of its heavy metal content, poses serious threats to the environment and human health. However, ES might have potential use as colouring agent due to its high concentration of chromium and nickel. Thus, the present work aims at studying the effect of ES incorporation into stoneware bodies. The influence on the final characteristics of fired samples, ES amount and pre-treatment were analysed. It was found that stoneware pastes having uniform brownish hues can be obtained with only 3 wt.% of sieved (<212 mu m) ES. The obtained specimens have, once fired, the desired technical and aesthetical characteristics. Further, leaching tests confirmed the immobilisation of hazardous ES species in the ceramic matrix. Hence, it can be concluded that this waste can be used as colouring agent of stoneware pastes substituting commercial pigments and contributing to more sustainable consumption and production in the ceramic sector.
subject category
Green & Sustainable Science & Technology; Environmental Sciences; Environmental Studies
authors
Vilarinho, IS; Carneiro, J; Pinto, C; Labrincha, JA; Seabra, MP
our authors
acknowledgements
This work is financed by Portugal 2020 through the European Reginal Development Fund (ERDF) in the frame of the Operational Competitiveness Internationalization Programme (POCI) in the scope of the project ECOGRES + NG POCI-01-0247-FEDER-033853 and in the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 and UIDP/50011/2020, financed by national funds through the Portuguese Foundation for Science and Technology/MCTES.