الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
Wastewater from the textile industry is regarded one of the main sources of pollution due to the great demand for textile products and auxiliaries resulting in a proportional rise in the production and application of synthetic dyes. Effluent samples were collected from 6 textile factories in Egypt, physicochemical characteristics (Color, smell, temperature, pH, BOD, COD,TDS and TSS) of the various wastewater samples were determined. Results showed elevated levels of Color, smell, temperature, pH, BOD, COD, TDS and TSS in the 6 factories which indicated environmental impact of textile effluents. Five textile dyes, Remazol blue, Remazol red, Remazol yellow, Remazol black and Orange 2RL were used for the decolorization in the present investigation. Fungal strains native to the sampled areas were isolated, purified, and screened for their decolorization activity of the tested five dyes. Two fungal species, Aspergillus niger and Aspergillus fumigatus have been observed to be the best isolated fungi for decolonization of tested dyes. In order to optimize their decoloration capacity, Aspergillus niger and Aspergillus fumigatus were further researched. A. niger showed highest decolorization with Remazol blue, Remazol red, Remazol black , Remazol yellow and Orange 2RL, after four days of incubation. Also A. fumigatus showed maximum decolorization with Remazol blue, Remazol red, Remazol black and Remazol yellow after four days of incubation, while in case of Orange 2RL 100% decolorization achieved after 2 days. The highest decolorization value of the five dyes by both A. niger and A. fumigatus was acquiered at the initial dye concentration of 100 mg/L,
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and it reduced above this concentration which may be due to dye toxicity. It was observed that there was a broad variety of pH values for tested fungi to grow and decolorize the 5 dyes, with optimum value at pH 3 and 4 for both A. niger and A. fumigatus. A. niger showed highest decolorization of Remazol blue and Remazol red with yeast extract, Rmazol black with (NH4)2SO4 , Remazol yellow with NH4Cl and Orange 2RL with peptone . A. fumigatus showed highest decolorization of Remazol blue, Remazol red and Remazol yellow with (NH4)2SO4, Remazol black with yeast extract and Orange 2RL with NH4Cl. Fourier Transform Infrared Spectroscopy (FTIR) performed chemical characterization of both fungi. The biosorption data have been analyzed using Langmuir and Freundlich isotherms. The equilibrium sorption data on the Langmuir isotherm model was better fitted than the Freundlich model on the basis of R2; except in case of Remazol blue with A. fumigatus, the adsorption obeys not only to the Langmuir model but also the model of Freundlich. Results showed that the indigenous fungi A. niger and A. fumigatus have the ability to remediate the dye from the effluent. It may be suggested that contaminated dye sites may be restored through a low-cost bioremediation process with indigenous fungal species isolated from the dye disposal locations.
Keywords: A. niger, A. fumigatus, Physicochemical, Textile dyes, Decolorization, Optimization, Infrared Spectroscopy (FTIR), Langmuir and Freundlich isotherms.