This study describes the sorption of Cr(VI) by MgAl-NO3 hydrotalcite in a fixed-bed column. The sorbent was prepared via coprecipitation method and characterized by XRD, FTIR, BET surface area and pHzpc. The effects of operating parameters such as bed height, flow rate and inlet concentration were investigated in continuous mode. As a result, the exhaustion time increased with the increase of bed height, decrease of flow rate and inlet concentration. A mathematical model based on the constant pattern theory and the Freundlich isotherm was applied to predict the experimental data, and to evaluate the model parameters of the fixed-bed column. The developed model describes well the breakthrough curves at various operating conditions. The calculated volumetric mass transfer coefficient KLa depends directly on these conditions. KLa increased with increasing flow rate and inlet concentration, while remained almost constant with varying bed height.
Demirbas E, Kobya M, Senturk E, Ozkan T, Water SA, 30, 533, 2004
Goyer RA, Mehlman MA, Advances in Modern Toxicology: Toxicology of Trace Elements, John Wiley & Sons, New York (1977).
Carson BL, Ellis HV, McCann JL, Toxicology and Biological Monitoring of Metals in Humans, Lewis Publishers, Chelsea, Michigan (1986).
Environmental Protection Agency (EPA), Cincinnati, Ohio, Environmental pollution control alternatives: Drinking Water Treatment for Small Communities, EPA/625/5-90/025, California (1990).
Coulson JM, Richardson JF, Chemical Engineering, vol. 2, in: Buckhurst JR (Ed.), fifth ed., Particle Technology and Separation Processes, London, New York (2002).
Ruthven DM, Principles of adsorption and adsorption processes, Wiley, New York (1984).
Yang Q, Zhang J, Yang Q, Tang X, Yu Y, Yang G, Trans. Tianjin Univ., 17, 51, 2011
APHA, Standard Methods for the Examination of Water and Wastewater (21st edn.). In: Eaton AD, Clesceri LS, Rice EW, Greenberg AE, Franson MAH (eds.), American Public Health Association, American Water Works Association, Water Environment Federation, USA (2005).