Influence of Na₂O/Al₂O₃ and SiO₂/Al₂O₃ ratios on the immobilization of Pb from electric arc furnace into the fly ash based geopolymers

¹ Faculty of Civil Engineering, University of Montenegro, Džordža Vašingtona bb, 81000 Podgorica, MONTENEGRO
² Faculty of Metallurgy and Technology, University of Montenegro, Džordža Vašingtona bb, 81000 Podgorica, MONTENEGRO
³ Institute of public health, Džona Džeksona bb, 81000 Podgorica, MONTENEGRO
⁴ Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11120 Belgrade, SERBIA

^a rzejak@t-com.me
^b irena@ac.me
^c dil@t-com.me
^d bojanavukcevic@yahoo.com
^e dragob@ac.me
^f VRRadmilovic@tmf.bg.ac.rs

Abstract

Electric arc furnace dust (EAFD) is by-product of iron and steel scrap remelting in electric arc furnace. This waste is classified as a hazardous material due to the leaching of heavy metals into the environment. Geopolymeryzation of fly ash into construction materials called - geopolymer is a considering as a possible way of immobilization of heavy metals from EAFD. Mechanical properties and chemical stability of geopolymers are mostly determined by the ratio between main oxides, Na2O, Al2O3 and SiO2. In this paper we have investigated possibility of Pb immobilization from EAFD into the fly ash based geopolymer. Geopolymers are synthesized at different Na2O/Al2O3 and SiO2/Al2O3 ratios. Compressive strength and chemical stability of geopolymers with respect to the leaching of Pb in water according to the EN 12457 regulation were tested. The results have shown that Na2O/Al2O3 and SiO2/Al2O3 ratios have influence on the compressive strength of geopolymers and Pb release in the water environment.