Synthesis of nano-hydroxyapatite chitin/chitosan hybrid biocomposites for the removal of Fe(III)

Biocomposites made up of nano-hydroxyapatite (n-HAp) with chitin and chitosan have been prepared and used for the removal of Fe(III) from aqueous solution. The sorption capacity (SC) of n-HAp, n-HAp/chitin (n-HApC) composite and n-HAp/chitosan (n-HApCs) composite was found to be 4238, 5800 and 6753 mg/kg respectively. Batch adsorption studies were conducted to optimize various equilibrating conditions like contact time, pH and co-ions. The sorbents were characterized by FTIR and EDAX analysis. The sorption process follows Langmuir isotherm. Thermodynamic studies revealed that the sorption of Fe(III) on these composites is spontaneous and endothermic in nature. Both the composites showed higher SC than the n-HAp.