2. Experimental
2.1. Materials
Palm oil was purchased from Morakot Industries Public Company Limited, Thailand. The density and molecular weight of the oil were measured to be 0.868g/cm3 and 851.06 g/mole, respectively. The duck and chicken eggshells were collected as wastes from university cafeterias. The eggshell was rinsed with water to remove dust and impurities, and was then dried in an oven. All chemicals were analytical-grade reagents (Merck, >99% purity) and were used as received.