Adsorption of Iron (II) ions from aqueous solution using Miscanthus biochar as a sustainable bioresource – preliminary batch studies

<p dir="ltr">This study examines the feasibility of using mischanthus biochar to remove Fe²⁺ ions from a neutral solution, a situation commonly found in well boreholes; this is increasingly relevant in water-stressed areas, where cheap decentralized water treatment is more appropriate. Mischanthus biochar produced at 700°C was investigated for its capacity to adsorb iron (II) ions using 50mL solution batches at a starting a concentration of 1000 mgL^-1 at pH 7.0. It was found that a biochar dosage of 1g removed up to 90% of iron (II) ions and that adsorption kinetics were pseudo-second order, showing a prevalence of chemisorption. Our data also showed that the adsorption followed the Langmuir isotherm model, with the Miscanthus biochar having an adsorption capacity of around 40 mgg-1, similar to previous studies at the same conditions. This study demonstrated that even without post-treatment, miscanthus biochar is feasible as an adsorbent of Fe²⁺ and further investigation to optimize a decentralized water treatment system is appropriate.</p>