Chitosan Immobilized on Silica Surface for Wastewater Treatment

Abstract

Adsorbents of natural origin are widely used for industrial wastewater treatment in order to replace current costly methods of heavy metals removing from solutions. For that purpose, immobilization of chitosan on the silica gel surface by crosslinking of adsorbed biopolymer with glutaraldehyde was carried out. Anchorage of chitosan on the silica surface was confirmed by IR spectroscopy. Concentration of immobilized chitosan was estimated using thermogravimetric analysis. The adsorption of microquantities of Zn(II), Cu(II), Cd(II), Pb(II), Fe(III), V(V) and Mo(VI) ions from aqueous solutions by obtained composite has been studied. The highest sorption capacities were observed with respect to zinc (0.46 mmol/g), molybdenum- and vanadium-containing ions (0.31 mmol/g). Diffuse reflectance electronic spectra of samples with different content of adsorbed metal and kinetic adsorption characteristics of the composite adsorbent were estimated. DOI: http://dx.doi.org/10.5755/j01.ms.20.2.4975

Keywords

• adsorption
• chitosan
• silica
• toxic metals removal
• wastewater treatment