ABSTRACT
This study, with a specific focus on the thermal influence, delves into the acid activation process of clay sourced from the aseni region of Kogi state. Samples of natural clay from aseni were subjected to acid activation treatments at two distinct temperatures: 200°C and 400°C. Post-treatment, the clay underwent structural transformations, scrutinized through techniques such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy-Energy Dispersive X-ray (SEM-EDX), and Brunauer-Emmet-Teller (BET) analysis.
The FT-IR results revealed the presence of functional groups such as OH stretching vibration, Si-O stretching in-plane vibration, and C=O stretching vibration indicates typical characteristics of clay minerals. However, at 200°C and 400°C there were slight variations observed with the frequencies which depicted the formation of new functional groups on the clay surface at elevated temperatures. Results of BET analysis reveal the following: for untreated aseni clay, surface area (BET) – 171.1 m2/g, pore volume – 0.083 cm3/g, pore diameter – 2.112 nm. Activated clay at 200°C yielded surface area (BET) – 295.2 m2/g, pore volume – 0.184 cm3/g, pore diameter – 2.423 nm. Activated clay at 400°C yielded surface area (BET) – 314 m2/g, pore volume – 0.176 cm3/g, pore diameter – 2.128 nm. The marginal increase in surface area, pore volume and pore diameter compared to the untreated aseni clay underscores the effect of acid and temperature on clay.
The SEM-EDX confirms alterations in elemental composition, particularly in decrease in chlorine concentration (from 0.85% in untreated clay to 0.74% and 0.49% in treated 200°C and 400°C respectively), silicon maintained its position as the biggest contributor to the clay samples averaging 53.51%, indicating it’s role in the primary composition of the clay sample and indicating the preservation and mineral composition despite treatment. Certain elements such as iron and potassium unveiled variable compositions indicating their susceptibility to interactions with the treatment process. These findings underscore the sensitivity of acidified clay to temperature variations and provide valuable insights for optimizing its properties for specific applications. Understanding these temperature-induced changes is essential for tailoring acid-treated clay to meet diverse industrial and environmental needs.
