Mann’s Cucumeropsis Seed Shell as an Oil Sorbent: Kinetic, Isotherm, and Thermodynamic Studies

Abstract

Oil spill cleanup using agricultural wastes, which otherwise cause environmental contamination, has gained popularity. In this study, the feasibility of using Mann's cucumeropsis seed shell, a commonly found agricultural waste, as an oil spill mop, was investigated. To identify the surface characteristics of the seed shell, SEM and BET analyses were employed. Batch crude oil sorption tests were performed under various adsorption conditions to determine the effects of initial oil concentration, contact time, adsorption temperature, and adsorbent dosage. Kinetic study of the sorption process involved the pseudo-first order, pseudo-second order, Elovich, and intraparticle diffusion models. Isotherm analysis involved the Langmuir, Temkin, Freundlich, and Dubinin-Radushkevich isotherms. Additionally, the thermodynamic parameters for the sorption process were established. SEM analysis revealed the porous nature of the seed shell's surface. The BET surface area was 313.2 m²/g. The oil sorption process conformed best to the pseudo-first-order kinetics and Langmuir isotherm. The monolayer sorption capacity of the seed shell was 13.072 g/g. The sorption process was exothermic, with some order at the adsorbent–mixture interface. The study's findings demonstrate that Mann's cucumeropsis seed shell is a potent oil sorbent that is safe for the environment and can be enhanced for use in cleaning up oil spills.