Diethylaminoethyl dextran/epichlorohydrin (DEAE-D/ECH) hydrogel as adsorbent for murexide

This study describes the dyestuff removal ability of diethylaminoethyl-dextran-epichlorohydrin (DEAE-D-ECH) polymeric adsorbents. The interaction between DEAE-D-ECH hydrogel and a water-soluble dyestuff, murexide (Mu), was investigated. The effect of different parameters on Mu adsorption efficiency was examined in detail. The equilibrium swelling capacity of DEAE-D hydrogel was determined by swelling in water and dye solution. Scanning electron microscopy micrographs and FTIR spectra, before and after the adsorption of Mu on the hydrogel, were used to explain the adsorption. Additionally, kinetic adsorption ability was well described by the pseudo-second-order kinetic model. The equilibrium data were best described by the Langmuir isotherm model. According to the calculated thermodynamic parameters (Delta G degrees, Delta H degrees, and Delta S degrees), the adsorption process is spontaneous and endothermic.