Operties of higher strength, high temperature resistance, climate resistance, low permeability, and acid corrosion resistance [91], has been studied extensively. Geopolymer concrete (GPC) is composed of aggregates and alkali-activated aluminosilicate components, such as aluminosilicate components including fly ash (FA), metakaolin (MK), and ground granulated blast furnace slag (GGBS), and so forth. [124]. Beneath the action of an alkali activator, GPC undergoes geopolymerization and generates an amorphous three-dimensional network structure of Indisulam Epigenetics silicon-oxygen tetrahedron and aluminum-oxygen tetrahedron connected via bridge oxygen [157], which endows the GPC with better acid corrosion resistance when compared with the OPC concrete [18]. It is actually reported that the acid corrosion resistance of OPC mainly depends upon the hydration item and the good quality on the protective layer [19,20]. Even so, for GPC, it can be the depolymerization of aluminosilicate polymers plus the liberation of silicic acid which affect its acid corrosion resistance [20,21]. Accordingly, the acid corrosion resistance of GPC is superior to OPC concrete for its far more steady cross-linked aluminosilicate polymer structure in GPC. In research so far, there are actually a big quantity of scholars which have studied the acid resistance of GPC. They found that the acid degradation in the calcium-free geopolymer (metakaolin) starts with an ion-exchange amongst framework cations (i.e., sodium) and protons in the acid solution. The protons induce an electrophilic attack, which outcomes in the ejection of aluminum (i.e., dealumination) from the Si-O-Al bonds in the binder [22]. Timothy et al. [23] studied the acid degradation mechanism of low-calcium fly ash binders and demonstrated its similar destruction course of action with a calcium-free geopolymer. The only distinction is the fact that the diffusing SO4 2- anions meet with counter diffusing calcium ions, causing the deposition of gypsum crystals inside the penetrated layer. Nuaklong et al. [24] made use of metakaolin as a partial substitution for high-calcium fly ash in geopolymer binders and concluded that the mixed binders exhibited higher resistance to acid attacks than the single binder because of the decline of calcium content of mixtures. Nevertheless, Mehta et al. [25] investigated the sulfuric acid resistance of high-calcium fly ash-based geopolymer concrete blended with an added calcium supply (OPC). They located that the inclusion of OPC enhanced the compressive strength of fly ash-based geopolymer concrete specimens significantly and 10 OPC addition exhibited greater acid resistance than 0 . Geopolymer mixtures prepared with various binding supplies show unique resistance to sulfuric acid, especially for calcium-free or calcium-based binding supplies. Thus, it is actually substantial to investigate the sulfuric-acid resistance of geopolymers respectively ready from unique binding supplies: metakaolin and low-calcium and high-calcium fly ash. Apart from, most scholars only take a single concentration of alkali activator into consideration [26,27], ignoring the influence of alkali activator concentration on the acid resistance of geopolymers. Different concentrations of alkali activator should be regarded to prepare the geopolymer mixtures. The work reported herein aimed to clarify the Brofaromine MedChemExpress effects of distinct binding materials and concentrations of alkali activators of GPC around the sulfuric acid corrosion resistance. Moreover, the acid corrosion resistance test within this function.
