Honeycomb-like hydrogel adsorbents derived from salecan polysaccharide for wastewater treatment

There is an emerging quest for water purification materials with high efficiency and low cost, while still being renewable and sustainable. In this study, a series of honeycomb-like composite hydrogels based on salecan polysaccharide and poly(acrylamide-co-sodium allylsulfonate) were developed by solution polymerization and were employed as adsorbents for removal of rhodamine B (RhB) dye from aqueous solutions. Adsorption of RhB onto the salecan-based materials was investigated as a function of salecan amount, initial dye concentration, gel dose, contact time and solution pH. The equilibrium adsorption data of RhB were successfully fitted to the Langmuir isotherm model with a maximum sorption of 71.6 mg/g. Furthermore, pseudo-second-order kinetic model matched the kinetic results satisfactorily, revealing that the dye sorption process was driven by chemisorption. More significantly, the designed gel adsorbents showed good reusability and acceptable regeneration ability. In conclusion, this work opens up a new horizon in the fabrication of salecan-based polysaccharide biosorbents for potential wastewater remediation application.