Volume No. 5 Issue No.: 3 Page No.: 656-660 January-March 2011

 

HEAVY METAL ADSORPTION CHARACTERISTICS OF A FREE FLOATING AQUATIC MACROPHYTE SPIRODELA POLYRHIZA

 

Prabhat Kumar Rai* and B. D. Tripathi

Department of Forest Ecology, Biodiversity and Environmental Sciences (FEBES), Mizoram University, Tanhril Campus, Aizawl, (INDIA)

 

Received on : April 14, 2010

 

ABSTRACT

 

In this paper, cadmium, zinc, and lead adsorption properties of nonliving Spirodela polyrhiza (L.) were investigated. Data obtained from the initial adsorption studies indicated that Spirodela polyrhiza (L.) was capable of removing cadmium, nickel, and lead from solution. The metal biosorption was fast and equilibrium was attained with in 20 minutes. Data obtained from further batch studies conformed well to the Langmuir Model. Maximum adsorption capacities (qmax) Spirodela polyrhiza were 6.15 mg/g for Pb(II).), 13.96 mg/g for Ni(II) and 44.9 mg/g for Cd(II). Kinetics of adsorption of cadmium, lead and nickel were analysed and rate constants were derived for each metal. It was found that the overall adsorption process was best described by pseudo second-order kinetics. The results showed that this free floating aquatic plant Spirodela polyrhiza can be successfully used for removal of cadmium, nickel and lead.

 

Keywords : Aquatic plants, Biosorption, Heavy metals, Duckweed, Spirodela polyrhiza

 

 

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