Cu and Cd Adsorption on Carbon Aerogel and Xerogel

Babes-Bolyai University, Faculty of Chemistry and Chemical Engineering, 11 Arany Janos str. RO-400028, Cluj-Napoca, ROMANIA

^a ccosmin@chem.ubbcluj.ro
^b iladiu@chem.ubbcluj.ro
^c vdanciu@chem.ubbcluj.ro
^d andrada@chem.ubbcluj.ro

Abstract

Carbon aerogel (CA) and xerogel (CX) were proposed as new carbon adsorbent materials for Cu and Cd ions from contaminated water (synthetic water samples). These materials were prepared by a sol-gel process that involves a polycondensation of resorcinol and formaldehyde in Na₂CO₃ catalysis, followed by a drying step, either in supercritical conditions of CO₂ to aerogel obtaining or in normal conditions to xerogel obtaining, and a pyrolytic step. Nitrogen adsorption, AFM, SEM, TEM and XRD were used for morpho-structural adsorbent investigation. Cu and Cd ions adsorption experiments were carried out in batch conditions under magnetic stirring. Adsorbent quantity and grain size influence over the adsorption efficiency were considered. Adsorption results expressed as adsorption capacities showed that prepared CA is a better adsorbent than CX. Adsorption capacities up to 14.2 mg g^-1 and 8.5 mg g^-1 were obtained for Cd²⁺ and Cu²⁺ adsorption on CA, respectively.