Green Transition in Slovenian Building and Civil Engineering Industry: 10 Years of Research on Alkali-Activated Materials and Alkali-Activated Foams

Abstract

The building and civil engineering industry yearly causes more than 40% of man-made CO2 and consumes raw materials for two-thirds of Mont Everest. To decrease the car-bon footprint and consumption of raw materials, alkali-activated materials (AAMs) are researched as an alternative to conventional building and civil engineering prod-ucts like cements, mortar, and ceramics. Ideally, locally available waste materials are used as ingredients: (i) as precursors that react with alkali and form an aluminosilicate network, and (ii) as fillers that get permanently encapsulated and safely stored in AAMs. The addition of gas bubbles and lightweight fillers transforms AAMs into alka-li-activated foams and alkali-activated lightweight materials that have the potential to be used as thermal and acoustic insulation materials. Although AAMs are researched worldwide, this review focuses on the state-of-the-art localised solely to Slovenia, par-ticularly on the materials and curing procedures used, as well as on the scientific con-tribution of the basic research. Besides, the year 2024 marks 10 years of research on al-kali activation of raw and waste inorganic materials in Slovenia. Keywords: Secondary raw materials; Alkali-activated materials; Alkali-activated foams; Low-temperature curing; Microwave curing; Circular economy