Remoción de nitratos presentes en aguas de consumo usando hidrogeles biodegradables de quitosano reticulado

Abstract

Cross-linked Oxalic acid/Chitosan Hydrogels (HGsQO) were synthesized and tested for the adsorption of nitrate in contaminated water. SEM, N2 adsorption/desorption and FTIR-ATR were used for the characterization of the new material. The FTIR-Spectra results evidenced electrostatic interactions between protonated amino groups of chitosan and oxalate ions duo to ionic crosslinked. The tests showed that the adsorbent is efficient in a wide range of pH (4-7), in these conditions the removal of nitrate occurred by electrostatic interactions, this was verified by analyzing the change of Z-potential before and after the adsorption process. Several models of adsorption kinetics were tested and the pseudo-second order model was the best fit. The experimental adsorption capacity at equilibrium (Qe) was high (22.03 mg.g-1) in comparison with other adsorbent materials based on chitosan. It can be concluded that HGsQO are alternative materials for nitrate removal.