Fabrication of a new polysaccharide-based adsorbent for water purification

Expanding the application of polysaccharide material has attracted tremendous attention in the fields of wastewater treatment, agriculture and biomedical engineering, on account of its tunable and unique properties. Herein, we employ a water-soluble, sustainable and low cost bacterial polysaccharide, salecan as a matrix, poly(acrylamide-co-itaconic acid) (PAI) as a synthetic component to synthesize salecan-g-PAI hydrogels through a simple chemical crosslinking method. Their physicochemical properties were fully characterized by various methods including Fourier transformed infrared spectroscopy, X-ray diffraction, thermogravimetry, scanning electron microscope and rheometry. We found that salecan not only acted as the interaction sites to regulate the water content of the developing hydrogels, but also endowed them with tailorable morphology. The designed salecan-g-PAI hydrogels exhibited excellent adsorption properties toward methylene blue (MB) dye, and the adsorption process could be well described by the pseudo-second-order kinetic and Freundlich isotherm models. Altogether, this study broadens the application of salecan polysaccharides and provides a new device for dye decontamination.