Influence of inorganic admixtures on the 11 angstrom-tobermorite formation prepared from steel slags: XRD and FTIR analysis

Journal article, 2014

Calcium silicate hydrate is synthesized from steel slag by adding lime and quartz by dynamic hydrothermal method at 185 degrees C. The products mainly consist of disordered calcium silicate hydrate, but more crystallized phase such as 11 angstrom-tobermorite forms for the presence of inorganic admixtures. The formation of tobermorite is affected by the types of ions according to XRD and FTIR results. Adding 2% crystallized tobermorite is beneficial to form the ordered structure; alkali cations and SO42- anions are effective accelerators; Al3+ plays a role of stabilization during the reaction. The products also vary with the initial alkalinities of steel slag.