Synthesis of diethylaminoethyl dextran hydrogel and its heavy metal ion adsorption characteristics

► Increasing of −CH2−CH2−N⊕H2−(C2H5)2 groups, network structure expands and increases swelling. ► It was thought that diethylaminoethyl group increases adsorption of metal ions. ► Decreasing order of metal removal strength of gel: Mn2+ > Zn2+ > Pb2+ > Cd2+. ► Hydrogel can be used by aim of removing unwanted water or chemical substances.