Design of sustainable geopolymeric matrices for encapsulation of treated radioactive solid organic waste

Among radioactive by-products generated by nuclear technologies, solid organic waste is drawing attention because of difficult management and incompatibility with the disposal strategies traditionally adopted. Recently, geopolymers have been proposed as valid green alternatives to cement-based matrices. In this work, novel geopolymeric formulations studied at laboratory scale encapsulate ashes from incineration surrogate further pursue sustainability circular economy goals. Indeed, most widely used precursor literature geopolymers, calcined kaolin, has totally replaced natural raw materials recycled industrial by-products. addition, a highly zeolitized volcanic tuff chosen improve intrinsic cation-exchange capacity geopolymer, hence enhancing waste-matrix interaction. The alkaline activation precursors, achieved without silicates any metal, resulted in promisingly durable matrix, whose chemical composition optimised provide compressive strength above 10 MPa after 28 days curing. A water-saturated sealed chamber provided optimal curing condition limit efflorescence mechanical properties. At least 20 wt% loading treated was achieved, compromising workability, setting time, strength, latter remaining within acceptable values. order demonstrate matrix durability, leaching behaviour thermal stability were preliminarily assessed immersion tests thermogravimetric analyses, respectively. leachability indices constituent elements far 6, which generally agreed requirement for Moreover, resistance not worsened water immersion. obtained results confirm promising properties new immobilization waste.