Corn Stalk Biomass as an Efficient Biosorbent for Aqueous Cobalt (II) Ions Removal
Oboyi Matthew Echeofun
*
Department of Chemical Sciences, Taraba State University, Nigeria.
Luntsi John
Department of Chemical Sciences, Taraba State University, Nigeria.
Christian Faithdin Chukwudera
Department of Chemical Sciences, Taraba State University, Nigeria.
Bello Caleb Bambur
Department of Chemical Sciences, Taraba State University, Nigeria.
Abdulhakim Olatunji
Department of Chemical Sciences, Taraba State University, Nigeria.
Johnson Sandra Fanwi
Department of Chemical Sciences, Taraba State University, Nigeria.
Kabiru Danlami
Department of Chemical Sciences, Taraba State University, Nigeria.
Habu Nuhso Eunice
Department of Chemical Sciences, Taraba State University, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
This study investigates the adsorption behavior of cobalt(II) ions from aqueous solutions using carbon synthesized from corn-stalk powder as a low-cost and eco-friendly adsorbent. The effects of key operational parameters adsorbent dosage, solution pH, contact time, and initial metal ion concentration were systematically examined to determine their influence on adsorption efficiency and capacity. Results revealed that cobalt(II) adsorption decreased with increasing adsorbent dosage, with a maximum adsorption capacity of 132.13 mg/g observed at a dosage of 0.1 g. The adsorption process was found to be pH-dependent, with the optimal removal recorded at pH 9.1, yielding a capacity of 129.63 mg/g. Contact time significantly influenced adsorption, as the capacity increased with time and peaked at 60 minutes (146.05 mg/g), beyond which equilibrium was attained. Additionally, increasing the initial concentration of cobalt(II) ions led to higher adsorption capacity, with the highest value (202.68 mg/g) observed at 250 mg/L. These findings suggest that corn-stalk-derived carbon is an effective and sustainable adsorbent for removing cobalt(II) ions, and optimizing operational conditions can significantly enhance its performance in water treatment applications.
Keywords: Adsorption, cobalt(II) ions, corn-stalk carbon, contact time, montmorillonite-silica nanocomposite, pH, water remediation, sustainable nanomaterials