Highly porous alkali-activated foams for water and wastewater treatment

In this thesis, new materials for water and wastewater treatment were developed via alkali-activation technology. Alkali activation is a process that involves a chemical reaction between a solid aluminosilicate precursor and an alkaline activator, at temperatures below 100 °C. Alkali-activated materials are of interest in water and wastewater treatment due to their low-energy, cost-effective preparation process, reduced carbon emissions, and excellent properties such as high mechanical strength or ion exchange capacity. The raw materials studied in this thesis were blast furnace slag, a by-product from iron manufacturing, and metakaolin, a calcined natural clay. Both are available in Finland. The thesis focuses on the development of new production routes for porous alkali-activated materials, and to respond the water pollution with these materials. The thesis made completely new research openings for alkali-activated materials in point-of-use water disinfection and microplastics separation from water. The results demonstrate that porous alkali-activated materials could be sustainable options for conventional ceramic water filters in these applications.