Reusing Ceramic Waste as a Precursor in Alkali-Activated Cements: A Review

Concrete and ceramic products are among the most widely used materials in the construction sector. The production of ceramic materials has significantly grown in recent years. Concrete is one of the most widely used materials worldwide and most of its carbon dioxide (CO2) emissions are attributed to Portland cement (PC) production. This review analyzed previous research works into the use of ceramic waste (CW) as a precursor in alkali-activated (AA) cements. The physico-chemical properties of different CW materials were analyzed, and the properties and environmental impact of three main categories of AA CW cements were explored: those developed solely with CW; hybrid cements combining CW with traditional binders (PC, calcium hydroxide or calcium aluminate cement); combinations of CW with other precursors (i.e., blast furnace slag, fly ash, fluid catalytic cracking residue, etc.). The results evidenced that CW can be successfully employed as a precursor in AA cements, particularly in the context of prefabricated products where thermal curing is a prevalent procedure. When enhanced mechanical strength is requisite, it is feasible to attain improvements by employing hybrid systems or by combining CW with other precursors, such as blast furnace slag. This new alternative reuse option allows progress to be made toward sustainable development by reducing not only CO2 emissions and embodied energy compared to PC but also PC consumption and CW accumulation in landfills.