Work

Development of Porous Refractory Calcium Hexaluminate (CA6) Ceramic Material from Limestone Waste

Year: 2025

Type: article

Abstract: Calcium hexaluminate (CA6) is a refractory material with good thermal properties and intrinsic difficulty in densification.This study explored the use of Cariri Stone residue, a calcium carbonate-rich limestone from Ceará, Brazil, as a precursor for producing refractory ceramics containing this phase. X-ray diffraction and preliminary tests were conducted to determine the optimal conditions for its incorporation into ceramic refractories. The results showed that a mixture of Cariri Stone residue and alumina, with a molar ratio of 0.5 moles of calcium oxide to 6 moles of aluminum oxide, achieved the best formation of CA6 at 1500°C. Specimens calcined at 1400°C exhibited the highest apparent porosity, indicating potential for thermal insulation applications. These findings highlight the feasibility of reusing Cariri Stone residue as a precursor for producing refractory ceramics containing the CA6 phase, offering a sustainable and promising alternative.

Source: Materials Research

DOI: 10.1590/1980-5373-mr-2024-0615

Authors: A. G. S. Costa, M. L. Silva, A. C. A. Prado, D. B. Silva, T. M. B. F. Oliveira, W. B. A. Bezerra

Institutions: Universidade Federal de Campina Grande, Universidade Federal do Vale do São Francisco, Universidade Federal do Cariri

Language: English

Topic: Recycling and utilization of industrial and municipal waste in materials production

Subfield: Building and Construction

Field: Engineering

Domain: Physical Sciences

SDG: Responsible consumption and production

Open Access status: diamond

Funders: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Conselho Nacional de Desenvolvimento Científico e Tecnológico