Novel montmorillonite nanosheets-based hydrogel beads with high adsorption performance and structural strength for removal of dyes and heavy metals

A series of high-performance montmorillonite nanosheets (MMTNS)-based hydrogel beads (HG-Bs) are prepared with different amounts of MMTNS, acrylic acid, acrylamide, sodium alginate and polyvinyl alcohol. MMTNS can significantly enhance the adsorption performance and structural strength, showing porous structure, good reusability, and high adsorption capacity of 564.97 mg/g for methylene blue. Moreover, FTIR, EDS and XPS measurements indicate that methylene blue is adsorbed by HG-Bs mainly through the adsorption between methylene blue and carboxyl, amide functional groups in HG-Bs, and the cation exchange. HG-Bs also has good adsorption capacity of 130.3 mg/g for Cu2+ and 155.7 mg/g for Cd2+.