Optimization of Experimental Parameters for Co(II) Ions Biosorption onto Algae Biochars

In this study, the removal Co(II) ions from aqueous media using biochars obtained from the marine algae biomass is proposed. Due to the high content of carbon, marine algae biomass can be a suitable raw material for biochar production. Therefore, the biochars obtained by pyrolysis of algae biomass (Ulva lactuca sp.) at two different temperatures: 320°C (BC-320) and 550°C (BC-550) under limited oxygen conditions, were used as biosorbents for the removal of Co(II) ions in aqueous media. The biosorption process was examined as a function of initial pH, biosorbent dose, initial Co(II) ions concentration, contact time and temperature, and the optimal conditions were selected step by step. The highest biosorption efficiency for Co(II) ions was obtained at a pH of 5.0, biosorbent dose of 4.0 g/L, a contact time of 60 min and temperature of 22°C. Under these conditions, the experimental removal percent is higher than 99 %, when the initial concentration of Co(II) ions is in the range of 12- 71 mg/L.