The Usage of Modified Chitosan for the Removal of Hexavalent Chromium from Waste Water

Year 2019, Volume: 3 Issue: 1, 87 - 95, 27.06.2019

Nuran Deveci Aksoy

Abstract

This
study presents the results of chromate adsorption upon chitosan modified with
thiourea, glutaraldehyde. Firstly modified chitosan was synthesized by using thiourea, glutaraldehyde and
chitosan at different molar ratios and adsorption capacities were compared to
the original chitosan. The modified chitosan showed higher Cr (VI) retention
performance than the original chitosan. While the original chitosan had a
percent removal of 32% at an initial concentration of 50 ppm, the percentage of
chitosan removal improved to 99.9%. Kinetic and thermodynamic constants are
determined at appropriate ambient conditions and adsorption is defined by appropriate
adsorption isotherms. Langmuir isotherms were found to be suitable for
characterizing the adsorption of chitosan with the modified Cr (VI) ions. Under
appropriate experimental conditions, percentages of removal in Cr (VI) removal
studies by adsorption using modified chitosan reached 99% and adsorption
capacity of 442 mg/g was observed.Characterization of the modified chitosan and
original chitosan were characterized by FTIR (Fourier Transform Infrared
Spectroscopy), TGA (Thermal Gravimetric Analysis), XRD (X-ray Diffraction) and
DSC (Differential Scanning Calorimetry) .

Keywords

Adsorption, Chitosan, Chromium(VI)

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