Adsorptive separation of Pb(II) and Cu(II) using modified waste Lyocell fiber adsorbent was investigated in this research. The waste Lyocell fiber was functionalized through carboxymethylation of the hydroxyl moieties using sodium chloroacetate as modifying agent and was crosslinked with epichlorohydrin to provide water stability. The maximum equilibrium batch uptake in single metal system was 353.45 mg/g for Pb(II) and 98.33 mg/g for Cu(II), according to the Langmuir isotherm model. The adsorption rates were very fast and reached equilibrium within 3 and 5-10 min for Cu(II) and Pb(II), respectively. In competitive binary metal system, the uptake of Cu(II) largely decreased to 38.40 mg/g, and Pb(II) selectivity was observed. Elemental and functional characterization suggested that the adsorption proceeded by ion exchange between the adsorbent and metal ions. In a flow-through column system, adsorption followed by desorption aided in effectively eluting *260 mg of Pb(II) (out of *300 mg total adsorbed) from the Pb(II)-Cu(II) binary solution. Finally, the adsorbent was very effective in four successive adsorption-desorption cycles with over 99 % uptake and 94 % desorption efficiencies. The present study may provide an alternative option for waste fiber recycling and could be useful in recovering heavy metal ions from aqueous sources to complement their depleting reserves.

Static adsorption of Sb (III) on a porous biomorph-genetic composite of Fe2O3/Fe3O4/C (PBGC-Fe/C-B) was studied. The results showed that the kinetic curve of Sb (III) adsorption by PBGC-Fe/C-B had same change trend under initial concentration of 5, 10 and 50 mg/L. The fitting and regression analysis of four kinds of kinetic model indicated that, the adsorption kinetics of Sb (III) by the PBGC-Fe/C-B well follow the pseudo-second-order model (R2>0.9999). At different reaction temperature (25 °C, 35 °C and 45 °C), the adsorption capacity of Sb (III) by PBGC-Fe/C-B both increased with increasing the solution equilibrium concentration. While it showed a declined tendency with temperature increased. The Langmuir isotherm model (R2>0.98) and the Freundlich isotherm model (R2>0.95) had both better fitted with the equilibrium data.

The Kinetics and thermodynamic was studied in ammonia nitrogen adsorption experiment using bamboo charcoal. The results showed that the dynamical data fit well with the pseudo-second-order kinetic model. The positive value of ΔH° (42.065 kJ/mol) and the apparent activation energy of the reaction of adsorption (20.67 kJ/mol) indicated that adsorption apparent rate constant increased with increasing temperature.