Synthesis and characterization of novel iron-modified geopolymer cement from laterite clay as low energy material

A new type of geopolymer with an iron-oxygen-silicon linkage is synthesized and reported for the first time. The aim was to enable the iron-rich clay material (laterite) as a raw material for the geopolymerization. Iron was used in different ratios ranging 1-3 wt. % in the raw mix designing geopolymer followed by activation with concentrated alkali solutions of NaOH and KOH in different concentrations. The bonding of Fe-O-Si was confirmed from the FTIR peaks in NaOH- and KOH-based geopolymers. X-ray diffraction studies confirmed the formation of zeolitic, sodalite, and almandite phases. The final product has shown a compressive strength of 2371.8 and 1503 kN/m(2) and can be used as a construction material.