Application of ZnO–Fe3O4 Nanocomposite on the Removal of Azo Dye from Aqueous Solutions: Kinetics and Equilibrium Studies (original) (raw)
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Polish Journal of Environmental Studies
Dyes are synthetic organic compounds that are increasingly being produced and used extensively in the paper, leather, textile, plastic, cosmetic, and other industries. Approximately 70,000 ton of dyestuffs are discharged into waste streams each year by the textile industry [1]. The presence of even very low concentrations of dyes in water reduces light penetration through the water surface, precluding photosynthesis of the aqueous flora. Additionally, many dyes or their metabolites have toxic as well as carcinogenic, mutagenic, and teratogenic effects on aquatic life and humans. Hence, the removal of dyes from aquatic wastewater has became environmentally important. Various methods including photocatalysis [2], chemical oxidation [3], coagulation [4], electrochemical [5], and adsorption [6] techniques have been applied for the removal of dyes from aqueous solutions. Among these methods, adsorption has been found to be superior
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