Lightweight Alkali-Activated Material from Mining and Glass Waste by Chemical and Physical Foaming

Abstract

A foamed alkali-activated material (FAAM), based on tungsten mining waste (TMW) and municipal waste glass (WG) was fabricated by using aluminium powder and organic surfactant foaming agents. The compressive strength and density of the FAAM were investigated in terms of different parameters of production and formulation including curing temperature as well as the dosage of Na2O, foaming agent, foam catalyzing agent and stabilizing agent. FAAM made with aluminium powder consisted of smaller open macropores and exhibited higher compressive strength in comparison with those of larger closed macropores obtained by the organic surfactant counterparts. The final aluminium powder based FAAM reached a 7-day compressive strength in excess of 3 MPa and a density below 0.7 g/cm3 25 . The implementation of an appropriate amount of foam stabilizer led to a further 15% increase in compressive strength, 6% reduction in density and a thermal conductivity below 0.1 W/mK. The FAAM explored in this study represents an ideal material for building envelop insulation.