Removal of Zn (II) ions by dialdehyde 8-aminoquinoline starch from aqueous solution

Dialdehyde 8-aminoquinoline starch (DASQA) was synthesized by the reaction of dialdehyde starch (DAS) and 8-aminoquinoline. It was used to adsorb Zn (II) ions from aqueous solution. DASQA was characterized by element analysis, FT-IR spectra, SEM and BET. The results of FT-IR showed the difference between DAS and DASQA in the spectrum. The adsorption study revealed that 120 min and pH 5.0 were the optimal conditions for adsorption of Zn2+. Maximum adsorption capacity was found to be 1.915 mmol/g. The adsorption equilibrium data correlated well with the Langmuir isotherm model. With the degree of substitution (DS) of the DASQA increased, the adsorption capacity increased gradually, which can also be reflected in the results of BET. Moreover, higher temperature was preferable to the adsorption since it was endothermic.