Phase dissolution and improving properties of completely decomposed granite through alkali fusion method

Low-reactive completely decomposed granite (CDG) was successfully synthesized by thermal activation with the addition of NaOH at low alkali/CDG mass ratio 0.1/1. During alkali fusion, degree amorphicity CDG rich in kaolinite (Al2Si2O5(OH)4) increased and a significant reduction peak intensities occurring between 20 45 (o2 theta) observed. Reactivity analysis indicated that, initial requires high molar to provide proper dissolution, whereas fused exhibits reactivity (29Si = 555.57 ppm; 27Al 223.73 ppm) concentration. Moreover, results from setting time, varied 15 min, indicating that fusion is very effective for improving dissolution under Na2SiO3 solution. However, time decreases as reaction accelerates. FTIR presented lower wavenumber band around 975 cm−1, confirming decline crystalline phases. In addition, SEM-EDS characterization alkalinity showed compactness structure due liberation enough sodium aluminosilicate gel. Finally, mechanical test (4.75–39.55 MPa) water solubility inferred enhancing up 15% GGBS, can be optimally recycled an alternative source material produce geopolymers.