Investigations on the possibility of natural hemp fibers use for Zn(II) ions removal from wastewatersAutori: Carmen Paduraru, Lavinia Tofan
Data aparitiei: November/December 2008
Revista: Environmental Engineering and Management Journal › Vol. 7 › Nr. 6
ISSN: 1843 - 3707
Natural hemp fibers have been evaluated for Zn (II) ions sorption from diluted aqueous solutions. In order to establish the optimum conditions, the effect of initial pH of solution, hemp dose, Zn (II) concentration, temperature and contact time of phases on the Zn (II) sorption by natural hemp has been studied. To model the Zn (II) sorption at three different temperatures the Langmuir and Freundlich isotherms have been used. The Langmuir maximum sorption capacities were determined as being of 0.2545, 0.3238 and 0.3754 mmol/g at 50C, 200C and 500C, respectively. In order to evaluate the thermodynamic feasibility of the Zn (II) sorption process, free energy change (?„G), enthalpy change (?„H) and entropy change (?„S) have been calculated on the basis of Langmuir constants. The constants of the pseudo first sorption rate, kâ€™, determined by means of Lagergren equation is 6.678x10-3min-1. The results of this study suggest that the natural hemp can be efficiently used in the removal of Zn (II) ions from wastewaters with low content of the tested cation.