Geosynthesis of building and construction materials through alkaline activation of granulated blast furnace slag

Enhancement of Waste Foundry Sand Mechanical Properties Through Stabilization Using Slag Based Geopolymer Binder

“…NaOH pellets were added to distilled water to produce alkaline solution. The optimum curing concentration and liquid to binder (L/S) ratio were found to be 15 M and 0.15 respectively from the previous study by Sithole et al [11]. The alkaline activator solution was allowed to cool at room temperature for 24 h. After 24 hours, the alkaline solution was mixed with GBFS, the mixture was stirred continuously until homogeneity was attained and the binder was cured at optimum curing as reported by Sithole et al [11] 2.4 Preparation of the geopolymer specimens…”

“…Moreover, the process of obtaining clay consumes vast amount of energy and generate large quantities of waste material that needs to be land lled; the land for land lling is reducing all over the world [9,10]. Most of the developing countries have severe energy crisis causing power cuts and this puts more strain on the energy grid [11]. To address challenges above-mentioned many researchers [12, 13, 14, 15, 16, 17, 18, 19 and 20].…”

“…Tekin et al [31] reported that sodium hydroxide (NaOH) is more eco-friendly solution than sodium metasilicate (NaSiO3) in terms of CO2 emission. Hence, Sithole et al studied the feasibility of using a single alkaline activator NaOH to successfully develop GBFS-based geopolymer binder that achieved uncon ned compressive strength of 72 MPa at elevated temperatures [11]. Sithole et al study demonstrated that the synthesised geopolymer specimen is environmentally friendly and complies with American Society for Testing Materials (ASTM) C34-13, C129-14a and South African standard (SANS227: 2007).…”

Alkaline Activation of Basic Oxygen Furnace Slag Modified Gold Mine Tailings for Building Material

“…e results obtained were like the strength of PPC specimens of 33.4 MPa and 41.8 MPa, for similar curing periods [25]. Granulated blast furnace slag was alkaline activated by NaOH and KOH to develop a building and construction material [26]. Phosphate mine tailings were alkaline activated using NaOH, and slag was added to adjust the gel structure [27].…”

“…Ca was spread throughout the particles, and it was mainly detected on larger particles. e microstructures of GMT and BFS, before the geopolymerization process, showed loose particles, whose metrics were transformed to be compact and filled spaces due to the formation of geopolymer gel [26], after geopolymerization as presented in Figure 4.…”