Superhydrophobic sodium alginate/cellulose aerogel for the dye adsorption and oil-water separation

Abstract The wide application of polysaccharide-based aerogel is limited by its hydrophilicity. To solve this problem, sodium alginate/ sodium carboxymethyl cellulose (SA/CMC) with silica nanoparticles and methyl trimethoxysilane as hydrophobic modifiers was prepared in this study. The sodium alginate (SA) and sodium carboxymethyl cellulose (CMC) were selected because of their low cost and easy of combination with the other two materials. After the silane reagent modification, Ca 2+ crosslinking, surface plasma treatment, thermochemical vapor deposition and freeze-drying methods, the aerogel get density of 0.080 g/cm 3 , high porosity of 94%, three-dimensional porous structure with great adsorbed ability. This superhydrophobic SA/CMC aerogel exhibits excellent water stability, appropriate compressive strength and good adsorption capacity of cationic dye methylene blue (MB). And the adsorption process is analyzed by adsorption kinetics. Meanwhile, this aerogel gets great absorbency and efficiency towards varieties of organic solvents, which gives it great potential of being used in the field of oil-water separation, textile dye wastewater treatment, etc. Moreover, this aerogel is expected to be recycled after washing.