ABSTRACT
Catalysis, a key concept in chemistry and industrial processes, significantly shapes our environment by speeding up chemical reactions without long-term changes. It is an important component in various commercial and industrial processes, driving the production of fuels, medications, plastics, and agricultural compounds. Solid acid catalysts have become effective instruments in the quest for sustainable catalysis. Clay minerals is an abundant, cost-effective and renewable resource whose properties can be modified to act as solid acid catalysts capable of replacing mineral acids in various organic synthesis applications. In order to synthesize this green solid acid catalyst, clay from a study site in Omialafara in Ondo State, Nigeria was modified with hydrochloric acid solution in this study. 5g of pre-treated clay samples was subjected to 1% and 5% HCl treatments respectively. Characterization was carried out on both the untreated clay and 5% HCl modified clay using X-ray diffraction (XRD), Fourier- 6 transform infrared spectroscopy (FT-IR), Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), and Brunauer-Emmett-Teller (BET) surface area analytical techniques. The FT-IR spectra results revealed the presence of Si-O and Si-O-Al functional groups in both clay samples, however, the OH group was notably absent in the modified clay following hydrochloric acid treatment. SEM-EDX analysis identified the major elements as Si, Al, and O for both clay samples. Remarkably, carbon content was significantly reduced in the 5% hydrochloric acid modified clay sample, dropping from 30.2% in the untreated clay to 3.0%. The SEM micrographs showed that the untreated clay had large lumpy particles, while the hydrochloric acid treatment resulted in noticeable disaggregation of these particles. In terms of surface properties, the surface area decreased from 345.364 m2 /g in the untreated clay to 285.0m2 /g in the 5% hydrochloric acid modified clay, and the pore volume decreased from 0.198 cm3 /g to 0.176 cm3 /g. The pore size increased slightly from 2.132nm for the untreated clay to 2.138nm for the HCl treated clay materials, suggesting that the concentration of hydrochloric acid may not have been sufficient to achieve the desired increase in surface area needed for an effective heterogeneous catalyst. Ultimately, further investigation is required to determine the impact of the 5% hydrochloric acid modification on the clay's catalytic performance in relative to the untreated clay.
