Production of cellulose from Aegagropila Linnaei macro-algae: Chemical modification, characterization and application for the bio-sorptionof cationic and anionic dyes from water

Abstract

Marine algae wereprovedto begoodadsorbentsformany pollutants. In this work, Aegagropila Linnaei (Aegagropila L.) was treated with sodium hydroxideand sodium chlorite. The extracted cellulose content was 18.5%. It was functionalized with Dimethyl diallyl ammonium chloride and diallylamin co-polymer. The products were characterized using Fourier Transform Infra-Red (FT-IR), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and thermogravimetric analyses (TGA). The samples were studied as adsorbents of methylene blue(MB) and acid blue 25(AB25) in a controlled batch system. The effect of salts concentration (KCl, NaCl, and CaCl2), adsorbent dosage, pH, contact time and initial dye concentration on the adsorption mechanism was discussed. At equilibrium, the adsorption of MB and AB25ontoextracted and functionalized cellulose reached 109 mg/g and 139 mg/g, respectively. Under the same conditions, the adsorption capacity of AB25 and MB onto unmodified Aegagropila L. was, only, 32 mg/g and 47 mg/g. The pseudo second-order kinetic equation exhibited the optimal fitting results. The mean free energy (E = 70.71 to 223.6 Kj/mol), calculated from Dubinin-Radushkevich isotherm, suggested a chemi-sorption mechanism. Overall, the results confirmed that the studied products could be considered as valuable bio-sorbents of dyes from contaminated waters.