Water and Environmental Research Center
Seminars
20 November 2009
Studies on continuous removal of cadmium (II) ions by citrus peels in a packed bed column
Abhijit Chatterjee
Photo: Soumik Dutta
Abhijit Chatterjee setting up equipment to measure contaminants in water after it has been filtered through citrus peels in the packed bed column pictured to the right. Chatterjee performed this work in a lab here at the Institute of Nothern Engineering.
Abstract
Biosorption, the passive (metabolism independent) binding of pollutants by living or dead biomass, is a low cost technique for removing heavy metals from waste water. Citrus peels are cheap and abundantly available sorbents as they are a waste product from the fruit processing industry. My current research is focused on investigating the efficiency of citrus peels for removal of Cd (II) from aqueous solution in continuous mode. A column made of clear extruded polyacrylic with a length of 30 cm and a diameter of ¾ inch was packed with protonated citrus peels for this purpose. ConcentrationZtime profiles were experimentally determined and analyzed with varying operational parameters such as flow rate, influent cadmium concentration and amount of peels within the column. It was found that for a flow rate of 12 ml/min and a bed depth of 26 cm, the column can be operated for 24 hours without breakthrough for 10 ppm influent solution. In order to avoid clogging of the bed, the mechanical strength of the packing was increased by granulizing those peels by using different supporting matrixes such as sodium alginate and agar. This treatment also results in improved permeability through the column, but at the cost of slower mass transfer kinetics. The data show promise for the use of citrus peels in remediation of the mine tailings contamination, but the whole system needs to be optimized properly.