ISOTHERM AND KINETIC STUDIES ON FLUORIDE BIOSORPTION FROM AQUEOUS SOLUTION BY USING CUTTLEBONE OBTAINED FROM THE PERSIAN GULF

Biosorption is considered to be one of the favored treatment technologies for fluoride ion (F) removal from aqueous solutions. The aim of this study was to determine the efficiency of cuttlebone (cuttlefish bone) obtained from the Persian Gulf in the removal of F from aqueous solutions. The biosorption experiments were studied in batch systems at room temperature. The effects of experimental parameters biosorbent dose, contact time, pH, and initial F concentration were studied. The highest removal biosorption was observed at 100 g/ L of biosorbent, at 120 min contact time and an initial F concentration at 12 mg/L (88.52%). The Langmuir model fitted better than the Frendlich model and showed a homogeneous biosorption surface with the possibility of a monolayer biosorption of F by the biosorbent. The biosorption kinetic was controlled by the pseudo-second order and pore diffusion models. The results showed that cuttlebone can be used as an environmentally friendly, cheap, and effective biosorbent of F from aqueous solutions, particularly in the coastal areas of the Persian Gulf with high-F levels in the drinking water.