Adsorption Efficiency of Scotch Bonnet Shells as a Precursor for Calcium Oxide Nanoparticles and an Adsorbent for the Removal of Amoxicillin from Aqueous Solution

Abstract

Anduang Ofuo Odiongenyi_,  Ubong Ime Essien, Emmanuel Jimmy Ukpong and Ifiok Okon Ekwere

Scotch Bonnet shells (BN) have high CaCO₃   content which was utilized in the synthesis of calcium oxide nanoparticles (CaONPS) for application in the adsorption removal of amoxicillin from water. The synthesized CaONPS showed adsorption in the UV region and displayed a band gap of 4.02 eV. It displayed high thermal stability and good crystalline properties with average crystalline size and macrostrain values of 5.67 nm and 0.3252. The crystalline size decreases as the macrostrain increases. The BET surface area of the CaONPS was evaluated as 785.04 m²/g while other pore properties such as pore diameter and pore volume were 2.65 nm and 0.1679 cc/g respectively. The nanomaterials showed strong evidence of a microporous nature, based on their particle size and the appearance of the SEM micrograph. The synthesized CaONPS showed strong adsorption efficiency for amoxicillin in water with efficiency approaching about 100 % under varying and influencing conditions such as pH, ionic strength, temperature, time and initial dye concentration. The adsorption system created by the CaONPS and the amoxicillin could be explained by the Langmuir adsorption isotherm, Pseudo second order kinetic model, intraparticle diffusion and thin film diffusion model.