Preparation of chitosan/lanthanum hydroxide composite aerogel beads for higher phosphorus adsorption

In this study, chitosan and lanthanum hydroxide composite aerogel beads were prepared for phosphorus adsorption via co precipitation and supercritical carbon dioxide drying technique. The porous structure of composite aerogel beads was investigated by scanning electron microscope (SEM), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) measurements. The results showed that the aerogel bead with mass ratio of chitosan to lanthanum chloride 100:50 exhibited a larger surface area of 172.74 m2/g and a pore volume of 1.05 cm3/g, respectively. Also the phosphorus adsorption kinetics of the aerogel bead showed a faster adsorption rate and the larger adsorption capacity (148.33 mg/g) for phosphorus. In addition, adsorption kinetics model analysis showed that the phosphorus adsorption process fitted both pseudo-first order and pseudo-second order kinetic model.