Chemical Characterization of Pore Water of a Solidified Hazardous Waste

Abstract

Immoblilization of four heavy metals by solidification/stabilization with portland cement was studied over a range of total metal concentrations and water/cement ratios. Pore water concentrations of each metal were measured to provide information about the degree of immobilization at presumed metastable equilibrium conditions in the synthetic wasteform and about possible immobilization mechanisms. Leaching behavior of crushed samples over a wide pH range also provided information about leach resistance and possible binding mechanisms.

Cement stabilization of heavy-metal-containing wastes

“…Other, more soluble ions exhibit a direct correlation between solid and aqueous phase concentrations. Last, but not least, the dissolved concentration is pH-dependent (e.g., Trussel & Batchelor 1996;van der Sloot et al 2001;Sanchez et al 2002). The underlying mechanisms have been discussed in Spence (1993) and more recently by Glasser (1997); others will be discussed here in depth later in the chapter.…”