Optimization of geopolymer mortar incorporating heavy metals in producing dense hybrid composites

Abstract

The aim of this study is to examine capability of geopolymer in immobilization and entrapping of heavy metals bearing materials; also, dose optimization that will be more efficiently affect the resultant geopolymer structure will be studied. The main binder used for mortar preparation was water cooled slag in addition to air cooed slag as fine aggregate passing sieve of one mm in equal ratio, whereas the used activator was 8 % wt sodium hydroxide. The studied heavy metals bearing materials were barium sulfate, lead phosphate, lead slag and electric arc furnace dust used as partial replacement of water-cooled slag. Physico-mechanical characterization of each set of samples was conducted using XRD, FT-IR, SEM, compressive strength and bulk density. Results demonstrated that barium sulfate can be efficiently used up to 2%, lead phosphate up to 1%, lead slag up to 5%, and electric arc furnace dust up to 10%.