The Potential of Laterite Soils Deposit South Sulawesi as a Precursor for Na-Poly (Ferro-Sialate) Geopolymers

Abstract

Abstract.The main objectives of this study was to investigate the potential of lateritic soils deposit South Sulawesi, Indonesia as a precursor for Na-poly(ferro-sialate) geopolymers. The samples of laterite soils were taken from three different regions, namely Sidrap, Bone, and Gowa regency. The soil was clean, grounded, sieves 200 mesh, and dehydroxylated at 750 o C for 2 hours. The x-ray fluorescence (XRF) and energy dispersive spectroscopy (EDS) were used to examine the chemical compositions of the soils. The geopolymers was synthesized through alkali activation method by adjusting the molar oxide ratios of SiO 2 /(Al 2 O 3 +Fe 2 O 3 ), Na 2 O/SiO 2 and H 2 O/Na 2 O in accordance with the chemical compositions of the soils. The functional groups of the resulting geopolymers were examined by using Fourier Transform Infra-Red (FTIR). The structure and phase of the resulting material were studied by using x-ray diffraction (XRD). The surface morphology of geopolymers was studied by using scanning electron microscopy (SEM). The mechanical strength of the materials was examined through compressive strength measurement. The results of this study showed that high strength Na-poly (ferro-sialate) geopolymers were successfully produced and characterized.

Role of Heat-Treated Laterite on the Strengthening of Geopolymer Designed with Laterite as Solid Precursor

“…Kaolinite, gibbsite, goethite and hematite are associated minerals that coexist with the relicts of partially dissolved quartz. They are the major components of compact laterites that are mostly under the form of complex and heterogeneous compounds containing mainly Fe2O3-Al2O3-SiO2-H2O [1][2][3].…”

Influence of the curing temperature on the properties of poly(phospho-ferro-siloxo) networks from laterite

“…These authors cured the final products at 70 °C for 1 h and at room temperature, respectively. Subaer et al [40] obtained the compressive strengths between 39 and 43 MPa while Kaze et al [41], their compressive strengths are in the range 10-18 MPa. By comparison with this work, the compressive strengths of the synthesis poly(phospho-ferro-siloxo) network obtained at room temperature (83 MPa) are highest than those obtained by Subaer et al [40] and Kaze et al [41].…”

“…Subaer et al [40] obtained the compressive strengths between 39 and 43 MPa while Kaze et al [41], their compressive strengths are in the range 10-18 MPa. By comparison with this work, the compressive strengths of the synthesis poly(phospho-ferro-siloxo) network obtained at room temperature (83 MPa) are highest than those obtained by Subaer et al [40] and Kaze et al [41]. Some researchers such as Louati et al [12], Tchakouté et al [16][17][18] assigned the higher compressive strengths of geopolymer cements obtained in acidic medium to the formation of berlinite which reinforces the structure of poly(phospho-ferro-siloxo) network.…”

“…This shows that the raw material used for producing poly(phospho-siloxo) network plays a crucial role in its hardening process. Concerning the laterite used as starting material to prepare geopolymer cement, Subaer et al [40] and Kaze et al [41] prepared geopolymer cements using laterite as an aluminoferrosilicate source and sodium waterglass Fig. 3 X-ray patterns of the selected poly(phospho-ferrosiloxo) networks, CLAT-N1, CLAT-N2, CLAT-N3, CLAT-N4 and CLAT-N7.…”

Development of Photoactive Nano TiO₂ Thin Film-Geopolymer Based on Laterite Soils Deposit Gowa Regency as Self-Cleaning Material

“…Laterite soils rich in iron and aluminum, and may contain a large amount of quartz and kaolinite, found at the surface or near surface in tropical and subtropical regions [1], with hot and humid climate, where heavy rainfall, warm temperature and well drainage lead to the formation of thick horizons of reddish lateritic soil profiles [2]. In Indonesia, laterite soil deposits can be easily found, one of them is in the province of South Sulawesi [3], Gowa regency laterite soils is considered as aluminosilicate minerals.…”