Application of Response Surface Methodology for Optimization of Lead Biosorption in an Aqueous Solution by Aspergillus niger

Department of Environmental Science, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Imam Reza Street, P.O. Box 46414-356, Noor, Iran.
Journal of Hazardous Materials (Impact Factor: 4.53). 07/2008; 154(1-3):694-702. DOI: 10.1016/j.jhazmat.2007.10.114
Source: PubMed


Response surface methodology was applied to optimize the removal of lead ion by Aspergillus niger in an aqueous solution. Experiments were conducted based on a rotatable central composite design (CCD) and analyzed using response surface methodology (RSM). The biosorption process was investigated as a function of three independent factors viz. initial solution pH (2.8-7.2), initial lead concentration (8-30 mg/l) and biomass dosage (1.6-6 g/l). The optimum conditions for the lead biosorption were found to be 3.44, 19.28 mg/l and 3.74 g/l, respectively, for initial solution pH, initial lead ion concentration and biomass dosage. Lead biosorption capacity on dead A. niger fungal biomass was enhanced by pretreatment using NaOH. Under these conditions, maximum biosorption capacity of the biomass for removal of lead ions was obtained to 96.21%. The desirability function was used to evaluate all the factors and response in the biosorption experiments in order to find an optimum point where the desired conditions could be obtained. The A. niger particles with clean surface and high porosity may have application as biosorbent for heavy metal removal from wastewater effluents.

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Available from: Farshid Ghorbani, Oct 05, 2015
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    Journal of Environmental Chemical Engineering 12/2013; 1(4):838–843. DOI:10.1016/j.jece.2013.07.022
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    • "Lead is a hazardous metal that is risky for living systems; therefore , many environmental agencies throughout the world have set limits on the lead concentrations in potable water supplies and industrial effluent discharge [1] [2]. Conventional methods for water treatment of hazardous metals include chemical precipitation, oxidation and ion exchange [3]. "
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    • "The high K m value of the kinetic experiment advocates that RBBR dye is not highly susceptible to laccase which confirms the essential of redox mediator for RBBR dye decolorization by laccase. Similarly, Roriz et al. [40] Q2 reported that the essential of redox mediator for RB5 decolorization by T. pubescens laccase. Hence, laccase based bioremediation systems could be a potential way for the anthracene derivative dyes decolorization. "
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