CDW waste as retardants of ions harmful to cement

Abstract

Circular Economy promotes the use of industrial materials during various phases of their active life. Construction and demolition waste (CDW) are one of those materials that can be reused several times without losing their properties, even improving them, by participating as substitutions in the Ordinary Portland Cement (OPC). The large volume of CDW wastes makes this substitution one of the most valued in the world of cement at present; it is for this reason that two types of aggregates, siliceous and calcareous, have been selected as potential substitutions in the OPC. In all cases, it is a question of obtaining easily accessible pozzolanic cements, with little contamination and great economy. In this work, binary mixtures of OPC and CDW waste have been prepared, manufacturing mortars that have been studied by means of XRD, XRF, SEM/EDX, and ion diffusion. The results obtained so far indicate that CDW¿s are suitable for substitution in the OPC in variable proportions that their use improves the slowing down of diffusion for certain ions, so that can link the pore size with the capture of these ions, considering certain pores as traps for the diffusion of polluting ions.