Preparation of Hydrogels Based Radix Isatidis Residue Grafted with Acrylic Acid and Acrylamide for the Removal of Heavy Metals

A series of hydrogels as biosorbents to remove heavy metal ions (Pb2+, Cu2+, and Cd2+) were prepared using Radix Isatidis residues material grafted with acrylic acid acrylamide. The surfaces residue/acrylic acid-co-acrylamide (RIR/AA-co-AM), residue/polyacrylamide (RIR/PAM3), residue/polyacrylic (RIR/PAA4) have a sponge-like, three-dimensional, highly microporous structure. all considerable swelling properties the rate RIR/PAA4 is highest at 9240%. possess high adsorptivity Pb2+, Cd2+. Under optimized conditions, maximum adsorption capacity RIR/AA-co-AM hydrogel 655.4 mg/g for 367.2 Cd2+, 290.5 Cu2+. Cd2+ Cu2+ slightly lower than that RIR/PAA4. In addition, process conforms pseudo-second-order kinetic equation Langmuir isotherm. Based on microstructure analysis kinetics, electrostatic ion exchange are identified mechanisms removal from water. It infers Chinese herb residue can be used effectively metals wastewater improve reutilization residue.