Parametric, equilibrium and kinetic studies on the removal of mercury using ion exchange resin

This experimental research was an investigation into removal of mercury by using a strong acid cation resin, 001 × 7. Parametric experiments were conducted to determine the optimum pH, resin dosage, agitation speed and the effect of change in concentration in the range of 50–200 mg/L. High resin dosages favoured better removal efficiency but resulted in lower uptakes. Equilibrium experiments were performed and fitted to Langmuir and Freundlich isotherm models. Langmuir model suited well to this study confirming the homogeneity of the resin surface. The Langmuir constants were estimated as q_max = 110.619 mg/g and K_L = 0.070 L/g at 308 K. Kinetic experiments were modeled using Pseudo second order model and higher values of R² (>0.97) were obtained. The Pseudo second order kinetic constants, namely, equilibrium uptake (q_e) and rate constant (k₂), were evaluated as 59.17 mg/g and 40.2 × 10⁻⁴ g mg⁻¹ min⁻¹ at an initial mercury concentration of 100 mg/L and temperature of 308 K.