Abstract
Oyster shells are by-products of oyster consumption and are commonly dumped as waste. On the other hand, used cooking oil (UCO) is a prevalent waste product of the food industry. It can contain high levels of degradation products such as peroxides and free fatty acids from repeated heating, which negatively impact the quality of oil and potentially pose health risks. This study was conducted to develop an adsorbent from oyster shell, determine its characteristics, and evaluate its performance in improving the quality of UCO. Oyster shell waste was collected and developed into an adsorbent based on its ability in reducing the peroxide value (PV) of UCO. The characteristics of the adsorbent such as adsorptive capacity, functional groups, surface morphology, pore size, were determined; and its performance in improving the quality of UCO in terms of peroxide value, acid value (AV), and color were tested. Results showed that the optimal preparation for oyster shell flour adsorbent (OSFA) was without activation, with a particle size of 106-201 µm. The adsorptive capacity of OSFA was 25% wt/vol of UCO. The presence of C=O and C-O functional groups was shown by FTIR analysis, while SEM analysis revealed a rough surface and porous layered structure, on adsorbent surface. The average pore size of OSFA was found to be 3.143 µm. The quality parameters of UCO were improved by OSFA through enhancing lightness and reducing PV and AV by 7.34-7.48% and 83.14%, respectively.
