This EArly-concept Grant for Exploratory Research (EAGER) project is to evaluate the feasibility of a novel approach towards producing binders for structural concrete applications through the carbonation process of waste/by-product metallic iron powder. The specific objectives include the determination of carbonation efficiency of iron powder under ambient temperature and pressure, the need to introduce complex formation agents and dissolution aids to increase the reaction product formation, and a preliminary understanding of the mechanical behavior of the binder. The reaction product(s) will be characterized using advanced characterization tools to discern the effects of source materials and processing conditions, and to link those to the mechanical properties of the material. The production of H2 as a by-product of the reaction requires careful consideration since it impacts the pore structure. Preliminary indications of the reaction kinetics in these systems will be arrived at through a combination of experimental techniques and simple models, which are expected to be vital towards further material design and process optimization for desired mechanical properties.
This project charts a novel course towards developing sustainable binder systems for concrete by not relying on portland cement hydration or alkaline activation of aluminosilicates. The use of a waste/by-product material (which is currently landfilled) as the major source material, and a greenhouse gas as the enabler of the reaction forwards the twin benefits of resource conservation and recycling, and CO2 sequestration. Establishing the feasibility of iron carbonate binder formation and adequacy of the material properties could accelerate the development of high-performance, net carbon-negative materials for a variety of applications including room-temperature processed moderate strength ceramic-like matrices. From an educational perspective, this research will continue the on-going efforts to mentor graduate and undergraduate students and to engage high-school students in research.
