Hilda Elizabeth Reynel-Avila

Kinetic and Thermodynamic Modeling of Cd+2 and Ni+2 Biosorption by Raw Chicken Feathers

Batch experiments were performed to model kinetic and thermodynamic data for Cd+2 and Ni+2 biosorption by raw chicken feathers (CFs) under different conditions. Results indicated that Cd+2 and Ni+2 sorption onto CFs occurred on the external surface of the biosorbent. Ion removal increased with pH, whereas both endothermic and exothermic stages where observed depending on temperature. Our calculated thermodynamic parameters showed that, below the temperature of 30°C, the metal uptake of Cd+2 and Ni+2 ions may be mainly controlled by a chemisorption process. However, for temperatures higher than 30°C, it is likely that sorption of both metals onto CFs is caused by a combination of both physical and chemical processes, especially for Ni+2 ions. Maximum sorption capacities were of 0.039 (Cd+2 ) and 0.065 mmol/g (Ni+2) at pH 5 and 30°C. Using 0.1 M HCl or CH3COOH as desorbing agents, approximately a 50% recovery for Cd+2 was achieved. The pseudo-second order and the general rate law models best fit the sorption kinetics data. The equilibrium metal uptake data was best described by the Sips isotherm.

Adsorption Processes for Water Treatment and Purification

This chapter covers fundamental aspects of adsorption process engineering. In particular, the importance of adsorption processes for water treatment is discussed and analyzed. Environmental impact of some key aquatic pollutants is also reviewed. Opportunity areas for adsorption process intensification are also highlighted in this chapter including a brief overview of the content of this book.

Analysis and modeling of multicomponent sorption of heavy metals on chicken feathers using Taguchi’s experimental designs and artificial neural networks

AbstractIn this study, we have used an integrated approach based on Taguchi’s experimental designs and artificial neural networks (ANNs) for the analysis and modeling of the simultaneous removal of cadmium (Cd2+), nickel (Ni2+), and lead (Pb2+) ions from ternary aqueous solutions using chicken feathers. Our results indicated that the multicomponent sorption of these heavy metals on chicken feathers is a complex antagonistic process. Specifically, chicken feathers showed a strong preference for the removal of Pb2+ ions in multicomponent solutions and the presence of these ions affected significantly the multicomponent removal of Cd2+ and Ni2+. This antagonistic sorption effect is more significant at pH 5 and the sorption preference of chicken feathers during heavy metal removal depends on the solution pH. Results of X-ray absorption near edge structure suggested that sulfide and carboxylic groups of chicken feathers appear to play a relevant role for the removal of heavy metal ions using this biomass. On t...