Comparison of Three Manufacturing Techniques for Sustainable Porous Clay Ceramics

• Published in: Materials Vol. 14; no. 1; p. 167
• Main Authors: Andreola, Fernanda, Lancellotti, Isabella, Sergi, Rachele, Cannillo, Valeria, Barbieri, Luisa
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 31.12.2020; MDPI
• Subjects: Aggregates; Agronomy; Ceramic powders; Ceramics; Clay; Consumption; Economic growth; Electrical resistivity; Environmental impact; fertilizer; Green buildings; Growth models; Lightweight; manual pelletization; Manufacturing; Materials recovery; Nutrients; porous clay ceramics; Porous materials; pressing; R&D; Raw materials; Recycling; Research & development; Room temperature; Scaffolds; shell scaffold; Sintering; Sintering (powder metallurgy); Soil porosity; Sustainability; Europe; porous clay ceramics; pressing; manual pelletization; shell scaffold; fertilizer
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma14010167

This study proposes different manufacturing techniques (manual pelletization, powder pressing, and "shell scaffold") to obtain lightweight clay ceramics containing recovery raw materials. The sintering in an electrical furnace (1000 °C, 1 h processing time) was conducted by traditional firing from room temperature, for pressed and shell-scaffold samples, while the flash heating (i.e., samples directly put at 1000 °C) was used only for the pellets. The porous materials (porosity 40-80%), functionalized with nutrients (K and P) in amounts to confer the fertilizer capability, gave suitable results in terms of pH (6.7-8.15) and electrical conductivity (0.29-1.33 mS/cm). Thus, such materials can be considered as feasible lightweight clay ceramics, with a positive effect on the soil. These findings permit us to hypothesize a potential use in green roofs or in agronomic applications.