A novel carbon aerogel prepared for adsorption of copper(II) ion in water

A novel carbon aerogel with network pore and surface group of hydroxyl was prepared from cellulose colloid, through sol-gel reaction, freeze-drying and carbonization. Surfactant like isooctyl alcohol ether phosphate was taken as structure inducer in sol-gel reaction, for construction of porous network in the prepared samples. Characteristic of a specific area about 725.12 m2/g and total pore volume about 0.64 cm3/g, the prepared cellulose-based carbon aerogel of CCA2, has a maximum capacity about 55.25 mg/g for Cu2+ in neutral aqueous solution. Its adsorption equilibrium can be reached within 10 min in an aqueous solution of pH7.0 at 25 °C, while desorption of Cu2+ need about 1 h eluted by HCl or HNO3 solution of 0.01 M. And regeneration of the carbon aerogel in adsorption of Cu2+ can be repeated for five times, remaining 96% adsorption capacity. It is also found in adsorption process the kinetics nicely follows pseudo-second-order rate expression, and the isotherm fits Langmuir model.