Electrochemically modified viscose-rayon-based activated carbon cloth for competitive and noncompetitive sorption of trace cobalt and lead ions from aqueous solution

A viscose-rayon-based activated carbon cloth (ACC) was electrochemically oxidised. As-received and electrochemically modified ACCs were characterised by sodium capacity, pH titration, elemental analysis and Fourier transform infra red (FTIR) spectroscopy analysis. Cobalt and lead noncompetitive sorption capacities for electrochemically oxidised ACC (EO) are 4.3 and 3.9 times, respectively higher than those for unoxidised ACC (UO). Cobalt and lead competitive sorption capacities for EO are 4.1 and 5.1 times, respectively higher than those for UO. Sorption of cobalt and lead onto EO was by ion exchange, while that onto UO was by surface complex formation. Affinity order of metals sorbed by EO and UO is Pb2+ > Co2+. Metal uptake onto EO increased with an increase in solution pH.