Removal of F− from aqueous solution using Zr(IV) impregnated dithiocarbamate modified chitosan beads

A novel, bio-based Zr(IV) impregnated dithiocarbamate modified chitosan beads (Zr-DMCB) was successfully synthesized for the adsorption of F− from aqueous solutions. Batch adsorption experiments were performed to evaluate the adsorption conditions, selectivity and reusability. The results showed that the saturation adsorption capacity was 4.58 mg/g at pH 7.0, 30 °C for 40 min. The adsorption kinetic data was fitted with pseudo-second-order model. Adsorption process could be well described by Langmuir isotherm model and the maximum adsorption capacity calculated from Langmuir isotherm equation was 7.78 mg/g. The adsorption capacity of Zr-DMCB for F− was significantly affected by co-anions. The adsorption mechanism of Zr-DMCB for F− was characterized by FTIR, SEM and EDX analysis. The results above indicated that Zr-DMCB is a very promising biosorbent for the removal of F− from aqueous solutions.