Adsorption of Fluoride from Aqueous Solution Using Low-Cost Bentonite/Chitosan Beads

Yi Zhang, Dongfeng Wang, Bingjie Liu, Xiang Gao, Wei Xu, Peng Liang, Ying Xu
2013 American Journal of Analytical Chemistry  
A new adsorbent namely bentonite/chitosan beads has been synthesized and studied for its defluoridation efficiency. Bentonite was activated and the beads were prepared using the inverse suspension polymerization method. The bentonite/chitosan beads (bentonite dosage of 3.0 g) showed an adsorption capacity of 0.895 mg/g whereas chitosan beads had only 0.359 mg/g. The optimal pH value was observed at pH 5 where the adsorbent reached the maximum defluoridation capacity of 1.164 mg/g. The effect of
more » ... mg/g. The effect of temperature, contact time and initial fluoride concentration on the adsorption capacity of the adsorbent has also been investigated. Scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX) and Fourier-transform infrared spectrometry (FTIR) were used to characterize the adsorbent. The adsorption of fluoride onto the adsorbent followed Freundlich isotherm model and pseudo-second order kinetic model. The fluoride loaded adsorbent could be regenerated using sodium hydroxide.
doi:10.4236/ajac.2013.47a007 fatcat:werr7sdbt5ckdg3jplzy7jg2ke