MAIZE BRAN AS A LOW-COST RESOURCE FOR Cu(II) IONS REMOVAL

The paper discusses the results of a study emphasizing the practical usefulness of a low-cost agricultural resource, “maize bran”, as sorbent for the removal of Cu(II) ions from wastewaters. To establish the optimum conditions of batch retention, the effect of initial solution pH, sorbent dose, initial concentration, time contact and temperature on Cu(II) sorption by maize bran has been studied. The kinetic description of the Cu(II)-maize bran sorption system was performed by the Lagergren pseudo-first-order equation. The equilibrium data at three different temperatures were processed according to Langmuir and Freundlich isotherm models. The Langmuir maximum sorption capacities were determined as 0.114, 0.132 and 0.149 mmol/g, at 4, 25 and 60 oC, respectively. To evaluate the thermodynamic feasibility of the Cu(II) sorption process, free energy change (G), enthalpy change (H) and entropy change (S) have been calculated on the basis of the Langmuir constants. The obtained results suggest that maize bran sorption may be a progression towards the elaboration of a prospective method.