Eco-friendly Enteromorpha polysaccharides-based hydrogels for heavy metal adsorption: From waste to efficient materials

Hydrogels are effective adsorbents for removal of heavy metal ions from wastewater due to their three-dimensional network and functional groups. In this paper, an eco-friendly hydrogel based on the polysaccharide extracted from the over-breeding macroalgae Enteromorpha prolifera was constructed and evaluated as an adsorbent for heavy metal ions. DFT calculation results confirmed that the carboxyl and sulfate groups of the Enteromorpha prolifera polysaccharides had certain chemical interactions with Pb2+, Cu2+ and Cd2+, which guarantee the high adsorption capacity for them. The interpenetration strategy used to construct the polysaccharide-based double network hydrogel, through which the mechanical properties, adsorption performance and recyclability of the hydrogel get strengthened synchronously. Overall, the constructed hydrogel is a competitive candidate material for heavy metal ion adsorption because of its low cost and biocompatibility, through which an innovative application of Enteromorpha prolifera from waste to treasure has been realized.