Valorization of paraffin wax waste in cement mortars: physical and mechanical behavior

The foundry industry is an essential part of the modern economy, manufacturing vast quantities of castings annually. However, this extensive production generates significant amounts of wastes, with the majority ending up in landfills. Efforts to repurpose these wastes are necessary not only to reduce landfill accumulation but also to preserve natural resources. One of the primary residues generated by foundries is paraffin wax waste, a byproduct of the investment casting industry. This technique, which has ancient origins, allows the creation of precise castings with important applications in the automotive, aircraft, and aerospace industries. Unlike waste foundry sand, which has been widely studied for reuse, the potential applications of paraffin wax waste remain unexplored. The paraffin wax waste functions as an organic phase change material (PCM). When incorporated into construction elements, PCMs help regulate the temperature in buildings due to their capacity of store and release thermal energy in response to environmental temperature fluctuations. These properties offer social, environmental, and economic advantages, such as enhanced thermal comfort, lower reliance on nonrenewable energy sources, and reduced air conditioning usage and costs. This characteristic make PCM valuable for enhancing energy efficiency and sustainability in the construction sector. Additionally, the construction sector significantly contributes to raw material consumption. Providing solutions to repurpose industrial wastes, such as paraffin wax, can improve resource efficiency and support the principles of a circular economy. The main objective of this study was to evaluate the physical and mechanical behavior of cement mortars with incorporation of paraffin wax wastes as a replacement for natural aggregates. The replacement content used were 20%, 40%, 60%, 80%, and 100%. The results indicated that the modified mortars exhibited satisfactory physical and mechanical performance, indicating possible future construction applications for this innovative material. By utilizing paraffin wax waste in cement mortars, this study presents a sustainable alternative for waste management in the foundry industry while contributing to the development of energy-efficient building materials.