The Effect of Anions and Cations on the Biosorption of Cadmium from Wastewater Using Garlic Leaves

The increasing pollution of urban wastewater into toxic compounds due to industrial development and growth is a threat for environment. Cadmium is a dangerous metal for creatures and is increasing due to the use of industrial wastewater for irrigation in agricultural land. Considering the importance and the high impact of the presence of different types of metal ions in industrial wastewater and the inhibitory effect of the presence of metal anions and cations for effectiveness of biosorbents in cleaning up dangerous metal ions, in this research, the optimal conditions for removal of cadmium ion with the leaves of garlic are investigated and then, removal percentages and equilibrium absorption capacity were studied in the presence of other anions and cations. In each experiment, one of the NO3-, Cu2 +, Zn2 +, Pb2 +, Al3 +, Fe2 + ions was examined. According to results, the presence of nitrate in a solution containing cadmium did not affect the rate of absorption by garlic leaf biomass. Also, copper, lead and iron cations had no effect on the absorption rate but zinc ions increases the rate of absorption of cadmium by garlic leaves and iron ions had a somewhat inhibitory effect on the absorption process but in general effect of the presence of other ions on the absorption and removal of cadmium ions from aqueous solutions was not significant. Therefore results of present experience investigation as an illustration of the fact, in the presence of a variety of metal ions can be generalized and garlic leaves can remove excess heavy metal ions from the wastewater successfully and the presence of other ions in a cadmium-containing solution will not have a significant inhibitory effect.