The effect of KOH activation on physicochemical properties of bentonite from Aceh Tamiang Available to Purchase

Alkali-activated materials offer a promising alternative for low-carbon building supplies. One of the phyllosilicate class of minerals, bentonite is crystalline and has a layered structure with 2:1 arrangement. The objective of the research is to understand how potassium hydroxide activation impacts the physicochemical properties of bentonite. In this investigation, various kalium hydroxide (KOH) concentrations were used to activate montmorillonite materials is 1 M, 1.5 M, 2 M and 2.5 M. Following activation, the materials were dried for 2 hours at 110 °C and then the activated bentonite was dried at 170 °C for 4 hours. Advanced analytical methods, such as powder XRD, FTIR, and SEM were used to characterize the activated bentonite. According to XRD analysis, the d₀₀₁ peak shifted to smaller 2θ angles and caused an increase in the basal spacing with increasing KOH concentration but the intensity of quartz (SiO₂) at 26.6° not change as the KOH concentration increases. The FTIR analysis indicated that the intensity of the bands 3632, 1639.5, and 785 cm⁻¹ that represented stretching vibration of -OH decreased at increasing KOH concentration. Analysis of the surfaces morphology revealed that KOH activation increased pore size in surface materials and more porous produce. Based on the results of the analysis, it can be concluded that the activation of bentonite using KOH did not show a significant change in the physicochemical characteristics of the bentonite structure.