Effect of Ca 2+ ions on naphthalene adsorption/desorption onto calcium oxide nanoparticle: Adsorption isotherm, kinetics and regeneration studies

• Published in: Environmental research Vol. 204; no. Pt B; p. 112070
• Main Authors: Kumar, J Aravind, Krithiga, T, Narendrakumar, G, Prakash, P, Balasankar, K, Sathish, S, Prabu, D, Pushkala, D Purna, Marraiki, Najat, Ramu, A G, Choi, Dongjin
• Format: Journal Article
• Language: English
• Published: Netherlands 01-03-2022
• Subjects: Adsorption; Calcium Compounds; Hydrogen-Ion Concentration; Ions; Kinetics; Nanoparticles; Naphthalenes; Oxides; Thermodynamics; Water Pollutants, Chemical - analysis; Regeneration; Calcium oxide; Naphthalene; Isotherm; Hydroxyl
• ISSN: 1096-0953

The adsorptive nature of calcium oxide nanoparticles in aqueous sample of naphthalene in presence of Ca
ions was estimated. Enhanced efficiency of calcium oxide regeneration (90%) with the aid of calcium chloride in the solution concentration of 0.002-0.1 M was depicted. The less degree of toxic naphthalene desorption merged with SEM, FTIR and XRD characterization data portrays the importance of naphthalene adsorption onto calcium oxide using calcium chloride for regeneration. Batch adsorption studies were performed to evaluate the operating parameters such as pH, naphthalene concentration, contact time and impact of Ca
on naphthalene study. The adsorption isotherm of naphthalene on calcium oxide nanoparticle was described by Langmuir, Freundlich, Temkin and Dubinin Radushkevich and theoretical maximum monolayer adsorption capacity was found to be 63.81 mg/g at 303 K. The adsorption kinetic best fitted with pseudo second order kinetic model. The positive influence of making the addition of Ca
ions into naphthalene solution for its rapid adsorption was elucidated which is leaded by a probable increase in sorption capacity for naphthalene molecules at lower concentrations. The stable nature of crystallinity of calcium oxide and a less degree of naphthalene molecules leaching during consecutive cycles of adsorptive process and nanoparticle regeneration was also scrutinized.