Valorization potential of solid wastes for the manufacture of electrical porcelains: a systematic review

In recent years, the increasing generation of polluting solid wastes has sparked serious concerns, demanding practical and sustainable actions, such as their valorization as alternative raw materials in manufacturing processes. This systematic review explores scientific articles published in the last fifteen years (2010 to 2025) on the valorization of solid wastes as alternative raw materials in the manufacture of electrical porcelains. The Scopus and Web of Science databases were consulted, resulting in the selection of 18 works that met the selection criteria. It was found that most of the works were carried out on a laboratory scale. A wide variety of solid waste materials have been used in the manufacture of electrical porcelains, including biomass ashes, mineral and industrial wastes, as well as recycled glass and ceramic materials. The review identified relevant aspects of the valorization of solid wastes in the manufacture of electrical porcelains: i) when used in optimal proportions, solid wastes contributes to low water absorption (< 0.5%), improved densification and, in some cases, increased mechanical strength and dielectric properties; and ii) solid wastes rich in fluxing oxides allowed for a reduction in sintering temperature, favoring sustainable and economically viable routes. However, excessive levels can cause defects, overfiring, bloating, and decreased electrical resistivity. Significant environmental concerns also arise for solid wastes containing heavy metals, requiring rigorous inertization control in the glass matrix. Finally, the review showed that the valorization of solid wastes in electrical porcelains is a current and promising topic that can lead to significant contributions to the circular economy and sustainable development.