EFFECTIVE REMOVAL AND RECOVERY OF LEAD FROM INDUSTRIAL WASTEWATERS USING NATURAL BIOMASS

Abstract

Rapid industrialization, urbanization and technological advancement in this century have drastically changed the biogeochemical cycles and balance of some of the heavy metals, thereby leading to environmental pollution in alarming proportions. Lead (i.e., Pb2+) is toxic to most organisms for concentrations higher than 0.05 mg/L, moreover, it is carcinogenic to animals. In the present study, batch biosorption of Pb2+ from wastewaters was studied using the nonliving biomass of Aspergillus sp. and Fusarium sp. isolated from soil. The specific metal removal increased with increase in initial lead ion concentration upto 500 mg/L observed with both the biomasses. A complete removal of the metal was observed at an initial metal ion concentration 50 mg/L and at pH 5.0. A maximum removal of 42.5 mg/g with Fusarium sp. and 37.3 mg/g with Aspergillus sp. was observed at pH 5.0 at 500 mg/L initial lead ion concentration. The adsorption equilibrium was obtained within 1h for all the concentration used. The adsorption equilibrium constants were obtained using both Freundlich and Langmuir adsorption isotherms. The desorption studies disclose the effective recovery of lead from the metal concentrated biomass using 0.1N Nitric acid solution within 0.5 h of time period increasing its effectiveness of reuse.