Authors : Sobhy M. Yakout and Ashraf A. Mostafa
Abstract: Rice straw activated carbon has been used for nitrate removal from aqueous solution. Results showed that increasing adsorbent concentrations increase the adsorption efficiency and decrease the adsorption capacity. At low adsorbent dose all types of sites are entirely exposed for adsorption and the surface gets saturated faster. At higher particle concentrations there is larger fraction of higher energy sites becoming unoccupied. Langmuir-Freundlich Adsorption Isotherm Model gave higher fitting to the experimental data compared to Freundlich and Langmuir isotherms. This due to Langmuir-Freundlich Model has three fitting parameters which not restricted to monolayer of molecules as it was in the Langmuir isotherm. A comparative study on the nitrate adsorption revealed that the prepared carbon had better nitrate adsorption capacity (82 mg g-1) as compared to other adsorbents. This suggests that straw based activated carbon is efficient nitrate adsorbents and that they possess good potential for nitrate removal in wastewater treatment.
Sobhy M. Yakout and Ashraf A. Mostafa, 2014. Equilibrium Isotherm Studies for Removal Nitrate from Aqueous Solution as Hazardous Anion in Animal System. Journal of Animal and Veterinary Advances, 13: 728-731.