Synthesis of Reusable functional magnetic chitosan adsorbent beads for the removal of Cr (VI) from water

Abstract

Industries along with industrial sites across the world are a major contributor of heavy metal pollution in water, among which Chromium possess the most toxic effects. To overcome this problem a productive method is needed for the removal of Chromium from water. In this regard, Beads based on chitosan, a non-toxic, biocompatible and biodegradable polymer, have showed great potential in numerous applications, including the removal of heavy metals from water. In this study Nano scale Iron Oxide particles produced by Sol Gel method were embedded in chitosan by using chemical co-precipitation method. The performance of Iron Oxide embedded chitosan beads (IECB) has been studied in a batch system, for chromium (VI) adsorption from industrial water specially. Concentration of chromium in solution was determined via UV Vis spectrophotometry on the basis of yellow color of chromate ions. Physiochemical properties of IECB were characterized through XRD, SEM, FTIR, VSM, contact angle and BET. Multiple factors influencing the adsorption attitude of IECB such as pH, temperature, initial concentration and interaction time of chromium ions were measured and 23.9 mg/g was the maximum adsorption capacity obtained at pH=4, 70⸰ C in 6 hrs. In this study, the Langmuir isotherm model (R2 > 0.991) and pseudo second order kinetics (R2 > 0.984) best fitted the experimental data. Moreover, thermodynamic parameters explain the Cr (VI) removal rate of Iron Oxide embedded chitosan (IEC) beads, which was maintained as high as 93.4% and 87% on the 4th and 5th runs respectively and at the end beads were successfully regenerated.

Industries along with industrial sites across the world are a major contributor of heavy metal pollution in water, among which Chromium possess the most toxic effects. To overcome this problem a productive method is needed for the removal of Chromium from water. In this regard, Beads based on chitosan, a non-toxic, biocompatible and biodegradable polymer, have showed great potential in numerous applications, including the removal of heavy metals from water. In this study Nano scale Iron Oxide particles produced by Sol Gel method were embedded in chitosan by using chemical co-precipitation method. The performance of Iron Oxide embedded chitosan beads (IECB) has been studied in a batch system, for chromium (VI) adsorption from industrial water specially. Concentration of chromium in solution was determined via UV Vis spectrophotometry on the basis of yellow color of chromate ions. Physiochemical properties of IECB were characterized through XRD, SEM, FTIR, VSM, contact angle and BET. Multiple factors influencing the adsorption attitude of IECB such as pH, temperature, initial concentration and interaction time of chromium ions were measured and 23.9 mg/g was the maximum adsorption capacity obtained at pH=4, 70⸰ C in 6 hrs. In this study, the Langmuir isotherm model (R2 > 0.991) and pseudo second order kinetics (R2 > 0.984) best fitted the experimental data. Moreover, thermodynamic parameters explain the Cr (VI) removal rate of Iron Oxide embedded chitosan (IEC) beads, which was maintained as high as 93.4% and 87% on the 4th and 5th runs respectively and at the end beads were successfully regenerated.