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Abstract
Arsenic occurs in both organic and inorganic forms in snatural waters but organic arsenic is of little importance as it goes through biotransformation and detoxifies through methylation. Inorganic arsenic occurs in -3, 0, +3, and +5 oxidation states in aquatic systems. Inorganic species of arsenic [As(III) and As(V)] represent a potential threat to the environment, human health, and animal health due to their carcinogenic and other effects.
The fly ash carbons occur in the residual coal ash as a result of the incomplete combustion process. Due to the increasing applications of activated carbons, fly ash carbon may take a special place amongst the carbon materials that are produced as a major co-product in the pyrolysis of different starting materials for the production of liquids and gases.
Fly ash collected from Kota thermal power plant(Rajasthan) was found to be class F fly ash as amount of SiO2> 60%.
Batch methods were used in this study to investigate arsenic adsorption using a clean, washed ash. ashStock solutions of As(V) were prepared by dissolving sodium salt heptahydrate of arsenic (Na2HAsO4⋅7H2O) . Experimental results indicated that pH had a significant effect on arsenic adsorption. Experimental equilibrium data of arsenic adsorption onto fly ash agglomerates can be fitted by Freundlich and Langmuir isotherm, while kinetics follows a pseudo second order model.
The negative values of ΔGo and ΔHo indicated that adsorption was spontaneous and exothermic process. The developed adsorption system is useful and can be used for the removal arsenic from contaminated water.##plugins.themes.academic_pro.article.details##
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