Utilization of Erythrina variegata orientalis leaf powder for the removal of cadmium

P Kumar, M Rao, N Chitti Babu, Ravi Kumar, & Venkateswarlu
2009 Indian Journal of Chemical Technology   unpublished
Removal of cadmium, a priority pollutant, is carried out by abundantly and freely available Erythrina variegata orientalis (Indian coral tree) leaf powder. The extent of removal depends on initial concentration of cadmium in the solution, pH of the solution, temperature, etc. A significant increase in percentage removal of cadmium is observed as pH is increased from 2 to 4. The percentage removal of cadmium increases marginally for pH of 4 to 7. As the initial concentration of cadmium is
more » ... ed from 23 to 188 mg/L, the % removal is decreased from 98.8 to 86.1%. Freundlich and Langmuir isotherm models well describe the data indicating favourable biosorption. The biosorption is endothermic, irreversible and follows pseudo-second-order kinetics, and rate constant is 0.23 g/(mg-min) for a dosage of 40 g/L. The equilibrium agitation time is 50 min.