Research Article
Biosorption of Fe(II) and Mn(II) Ions from Aqueous Solution by Rice Husk Ash
Figure 3
Effect of contact time on adsorption of Fe(II) and Mn(II) by RHA (metal concentration: 20 mg/L; adsorbent dosage: 0.6 g/100 mL; pH: 5 and 6, resp.).