Tahereh Shojaeimehr - Biotechnology Research lab., Chemical Engineering Department, Faculty of Engineering, Razi University
Farshad Rahimpour
Marzieh Sadeghi - Analytical chemistry lab., Chemistry Department., Faculty of Science, Razi University, Kermanshah , Iran

In the present study, for the first time, Gundelia tournefortii was used as a natural biosorbent of heavy metals such as Pb(II) in the batch system. The effect of the various parameters such as initial concentration, pH, and the contact time was investigated. The optimum conditions was found to be pH=5 and 60 min for the equilibrium contact time. The equilibrium behavior was studied by Freundlich, Langmuir, and Temkin isotherms. The Langmuir isotherm was showed the best accordance with the equilibrium data. The maximum adsorption capacity of lead ion estimated from Langmuir isotherm was 144.928 (mg/g) at 20 °C. The obtained results of this research show that Gundelia tournefortii is an excellent, natural, low-cost adsorbent with high

Gundelia tournefortii, Lead biosorption, Isotherm