Assessment of the potential of Fe-rich metallurgical residues as precursors for inorganic polymers

Several metallurgical slags with a wide range of chemical and mineralogical composition have been investigated aiming to identify the most promising precursors for the synthesis of inorganic polymers. The slags originate from... [ view full abstract ]

Several metallurgical slags with a wide range of chemical and mineralogical composition have been investigated aiming to identify the most promising precursors for the synthesis of inorganic polymers. The slags originate from Fe-rich metallurgical residues after being treated by thermal processes aiming to extract the valuable metals for their recovery. During the pyrometallurgical treatment of the residues several streams of different composition were obtained depending on the operating conditions. Screening tests were developed and used to quickly predict the feasibility of a given stream for this valorisation route. The materials were characterised in terms of chemistry (XRF and ICP/OES), mineralogy (quantitative XRD), micro-chemical composition (EPMA) and particle size distribution (laser diffraction/scattering). The structural characteristics of the raw materials were evaluated using FTIR spectroscopy. The screening test included reactivity assessment through dissolution experiments in NaOH solution and measurement of the heat of reaction by isothermal conduction calorimetry. The results revealed that several slags have a good potential for being used as precursors for inorganic polymers, which opens a novel valorisation path to be further explored.