Enhancing bricks with titanium dioxide ore waste: Mechanical and environmental assessments

• Published in: Construction & building materials 2024-11, Vol.451, p.138733, Article 138733
• Main Authors: Almeida, Stephanie Lya de Lima Castro de, Trevisan, Ana Paula, Junior, Ismael Laurindo Costa, Giona, Renata Mello, de Freitas, Adriane Martins, de Brito, Lais Montagnini, Passig, Fernando Hermes, de Carvalho, Karina Querne, Baraldi, Ilton José, Lied, Eduardo Borges
• Format: Article
• Language: English
• Subjects: Civil construction; Clay; Unreacted ore waste; Valorization
• ISSN: 0950-0618
• DOI: 10.1016/j.conbuildmat.2024.138733

Using residues, generated in various production chains of goods and services through developing new materials for civil construction, has proven to be a promising approach to addressing environmental issues. The residue generated during titanium dioxide (TiO2) production, commonly called Unreacted Ore Waste (UOW), presents potential utilization routes in the ceramic materials production chain, thereby avoiding disposal in industrial landfills. This study aimed to investigate the effects of combining UOW with ceramic blocks for any beneficial results. The properties of ceramic blocks obtained from the mixture of clay and UOW were evaluated after adding 5 %, 10 %, 15 %, and 20 % of UOW relative to the clay’s total mass. The ceramic blocks produced were assessed for their mechanical, photocatalytic, morphological, granulometric, mineralogical, and chemical properties. The results indicated that UOW did not negatively affect the structural properties studied. The addition of UOW led to a significant 9 % increase in the self-cleaning efficacy of the ceramic block produced. The textural parameter values of the ceramic blocks decreased with UOW incorporation due to more efficient particle packing. The surface area reduced from 16.6 to 9.1 m2/g, and the pore volume decreased from 0.045 to 0.025 cm3/g for samples from 0 % to 20 % UOW, respectively. Decreased porosity values contributed to increased compressive strength, resulting in a 6.5 MPa increment. The results suggested that the addition of UOW causes an increase in Al concentrations in leachate samples, from 647.64 to 5128.92 ppb for samples from 0 % to 20 % UOW, respectively. The presence of leachate and solubilized components from UOW impaired the germination of Lactuca sativa seeds. Based on the results, although the addition of UOW resulted in toxicity from the leachate/solubilized components, it did not adversely affect any fundamental properties of the ceramic materials. It can be incorporated up to 20 % into the process, replacing traditional raw materials. This suggests promising future trends in sustainable construction, with broader applications in the development of eco-friendly building materials. •Reusing UOW in red ceramics reduces waste and promotes sustainability.•The addition of UOW enhances self-cleaning properties and maintains mechanical integrity.•Incorporation of UOW up to 20 % is feasible despite its impact on seed germination.