M. abdelkreem

M. abdelkreem

Removal of strontium from aqueous solutions by adsorption onto orange peel: isotherms, kinetics, and thermodynamic studies

M. abdelkreem1*and DalalZ. Husein2

1Higher Technological Institute, 10th of Ramadan City, Egypt

2Chemistry Administration, Cairo, Egypt


The removal of Sr (II) from aqueous solution using orange peel (OP) and chemically modified ones with NaOH (NaOP) and KCl (KOP) was studied at varying pH, solid/liquid ratio, contact time, temperature range of (20-60ºC). Adsorption equilibrium was established in about 1h and the equilibrium data was analyzed using Langmuir, Freundlich, Temkin and Dubinin-Radushkevich adsorption isotherms. Langmuir model provided the best correlation for the adsorption of Sr(II) by the three adsorbents (OP, NaOP and KOP), and the mono-layer adsorption capacity for Sr(II) removal are 12.64, 54.94 and 52.36 for OP, NaOP and KOP mg/g, respectively. The adsorption kinetics followed the pseudo-second order kinetics model and thermodynamic studies showed the spontaneous and exothermic nature of the adsorption of Sr(II) by OP, NaOP and KOP. The present study emphasized that the chemically treated orange peel exhibited a high potential for the removal of strontium (II) from aqueous solution.

Keywords: Strontium, adsorption, isotherm, orange peel