C.A. UNUIGBE

This research focused on the adsorption of manganese ions (Mn²⁺) from MnSO₄ salt solution using kaolinite clay obtained from Aseni, Kogi State, Nigeria. This study aimed to evaluate the adsorption efficiency of kaolinite clay and to investigate the influence of process parameters, including contact time, pH, adsorbent dosage, and initial manganese concentration, on the removal efficiency. Batch adsorption experiments were conducted under controlled conditions, and residual manganese concentrations were determined using an atomic absorption spectrophotometer (AAS). The results revealed that adsorption efficiency increased with pH, contact time, and adsorbent dosage but decreased slightly with higher initial concentrations. Maximum removal was recorded at 78% at an initial concentration of 10Mn/l, 55.00% (1.0 g dosage), 22.0g (120 minutes), and 63.13% (pH 9). Equilibrium data fitted better to the Freundlich isotherm model, indicating multilayer adsorption on a heterogeneous surface, while the pseudo-second-order kinetic model provided the best correlation, suggesting a chemisorption-controlled mechanism.

The study concludes that kaolinite clay is an effective, locally available, and eco-friendly adsorbent for manganese removal from aqueous solutions, highlighting its potential for use in wastewater treatment and environmental remediation.