Lead (II) and nickel (II) adsorption kinetics from aqueous metal solutions using chemically modified and unmodified agricultural adsorbents

This paper discusses the kinetics of lead (II) and Nickel (II) ions adsorption from aqueous solutions using chemically modified and unmodified agricultural adsorbents at 28°C, pH 6.2 and 0.01M NaCl ionic strength. The removal of the two metals were found to increase with increase in chemical modification,the sequence being 1.0MOPF>0.5MOPF>UOPF. In addition Nickel (II) had a higher percentage removal than lead (II). The intraparticle diffusion rate constant (Kid) were determined to be 63.023 min-1 (Ni2+) and38.212 min-1 (Pb2+) for the 1.0MOPF adsorbent. The results show that the intraparticle diffusion model fits the sorption of lead (II) with higher coefficient of determination (r2) than Nickel (II), thereby indicating that the intra-particle diffusion may be the rate limiting step for Pb2+ sorption. The results from this study indicates that a good adsorbent for the removal of Ni2+ and Pb2+ can be obtained from both chemically modified and unmodified oil palm fruit fibr

Source Evaluation and Trace Metal Contamination in Benthic Sediments from Equatorial Ecosystems Using Multivariate Statistical Techniques

race metals (Cd, Cr, Cu, Ni and Pb) concentrations in benthic sediments were analyzed through multi-step fractionation scheme to assess the levels and sources of contamination in estuarine, riverine and freshwater ecosystems in Niger Delta (Nigeria). The degree of contamination was assessed using the individual contamination factors (ICF) and global contamination factor (GCF). Multivariate statistical approaches including principal component analysis (PCA), cluster analysis and correlation test were employed to evaluate the interrelationships and associated sources of contamination. The spatial distribution of metal concentrations followed the pattern Pb>Cu>Cr>Cd>Ni. Ecological risk index by ICF showed significant potential mobility and bioavailability for Cu, Cu and Ni. The ICF contamination trend in the benthic sediments at all studied sites was Cu>Cr>Ni>Cd>Pb. The principal component and agglomerative clustering analyses indicate that trace metals contamination in the ecosystems was influenced by multiple pollution sources

Nickel (Ii) Ion Desorption Kinetic Modeling From Unmodified and Chemically Modified Oil Palm (Elaeis Guineensis) Fruit Fibre Adsorbents

The desorption of Ni2+ from three oil palm fruit fibre adsorbents (UOPF, 0.5MOPF and 1.0MOPF) using five desorbing solutions showed a desorption efficiency following the trend, 0.1M HCl > 0.1MH2SO4 > 0.1MHNO3 > 0.1MNaOH >hot deionized H2O. The Elovich desorption constant, β values for the 0.1MHCl desorbent were: 6.45 X10-1, 5.57 x 10-1 and 4.34 x 10-1g. mg-.min-1 for UOPF,0.5MOPF and 1.0MOPF adsorbents respectively. The surface residence time values for the 0.1MHCl desorbent were; 32.3, 28.6 and 26.8 seconds for UOPF, 0.5MOPF and 1.0MOPF adsorbents respectively. Kinetic modeling analysis of the Elovich and pseudo-first order desorption equations, indicates that the latter model described the desorption of Ni2+ better.Keywords: Nickel, desorption, modeling, kinetics, Elovich, oil palm

Nickel (II) ion desorption kinetic modeling from unmodified and chemically modified oil palm (Elaeis guineensis) fruit fibre absorbents

The desorption of Ni2+ from three oil palm fruit fibre adsorbents (UOPF, 0.5MOPF and 1.0MOPF) using five desorbing solutions showed a desorption efficiency following the trend, 0.1M HCl > 0.1MH2SO4 > 0.1MHNO3 > 0.1MNaOH >hot deionized H2O. The Elovich desorption constant, β values for the 0.1MHCl desorbent were: 6.45 X10-1, 5.57 x 10-1 and 4.34 x 10-1g. mg-.min-1 for UOPF,0.5MOPF and 1.0MOPF adsorbents respectively. The surface residence time ح values for the 0.1MHCl desorbent were; 32.3, 28.6 and 26.8 seconds for UOPF, 0.5MOPF and 1.0MOPF adsorbents respectively. Kinetic modeling analysis of the Elovich and pseudo-first order desorption equations, indicates that the latter model described the desorption of Ni2+ better.Keywords: Nickel, desorption, modeling, kinetics, Elovich, oil palmJournal of Applied Science, Engineering and Technology, Volume 8, 200