| Using tegument collagen fiber as matrix, immobilized bayberry tannin was prepared through aldehydic cross-linking reaction, and adsorption behavior of the immobilized bayberry tannin to Mo(VI) and V(V) were studied carefully. Effect of the factors such as pH, temperature, initial concentration of metal ions to adsorption capacity were studied. And the adsorption equilibrium, adsorption kinetics, column adsorption kinetics, adsorption-desorption behaviors and the adsorption selectivity of Mo(VI) and V(V) in mixed metal ions solutions were investigated. Meanwhile, adsorption of the adsorbent to Mo(VI)—V(V) mixture was also investigated, including column kinetics of mixed adsorption, desorption and selectivity adsorption in mixed metal ions solutions. Finally, basing on the analysis of research data and results above, conceivable adsorption mechanism of immobilized bayberry tannin to Mo(VI) and V(V) were educed. Those studies had not only established an extensive application in environmental protection, metallurgy and 'iatrology, but also be scientifically valuable to enrich the knowledge of tannin chemistry and adsorption theory.The experiment data indicated that, adsorption capacity of the adsorbent to Mo(VI) and V(V) were 0.859mmol/g and 1.013 mmol/g respectively when initial concentration were 1.042 mmolMo/L and 2.75mmolV/L at 303K. Meanwhile, it had also showed that the adsorption capacity had little change with the raise of temperature, which meant the temperature had unconspicuous effect on adsorption capacity. The adsorption equilibrium data was analyzed by the Langmuir and the Freundlich equations further, from which we found that the adsorption of Mo(VI) could be described by the Freundlich equation, while that of V(V) fitted the Langmuir equation. This would indicate the adsorption mechanism of Mo(VI) and V(V) might differ from each other. The adsorption kinetics investigation of Mo(VI) and V(V) indicated that, the adsorption kinetics could be well described by the pscudo-second-order rate model, by which the adsorption capacity calculated inosculated with those determined by actual measurements.By the static desorption experiment of the two metal ions, it was found the immobilized bayberry tannin after adsorption of Mo(VI) could be easily regenerated by 0.02 mol/L EDTA solution, and the adsorption capacity had nearly unconspicuous change in three consecutive adsorption-regeneration cycles, this well indicated that 0.02 mol/L EDTA solution could be used as a desorption reagent and be used recurrently. And the data of column adsorption and desorption of Mo(VI) and V(V) illustrated that, the two meal ions on the adsorbent could be easily eluted by 0.02mol/L EDTA and 0.1 mol/L HC1 solution respectively. After desorption, the breakthrough of regenerated column moved up slightly, and the figure of the breakthrough curve was the same as the new one, which illustrated the immobilized bayberry tannin had a nice adsorption-desorption ability, and could be employed circulary but its efficiency decreased. The mixed column adsorption of Mo(VI)-V(V) illustrated that, at the room temperature when pH in the aqueous solution was 4.00, 0.1mol/L HC1 solution could be used for the elution of V(V) firstly while Mo(VI) in the same column didn't be eluted, then 0.02mol/L EDTA solution could be adopted to elute Mo(VI), and the concentration of the effluent were 23 times and 18 times high as that of the sample respectively, which showed the adsorbent had the use of separation and enrichment of Mo(VI) and V(V), and would have important application in water treatment in future.Mo(VI) and V(V) could be selectively adsorbed by immobilized bayberry tannin in mixture solution. The selective adsorption rate to Mo(VI) in Mo(VI)-Ni(II),Mo(VI)-Cu(II) and Mo(VI)-Re(VII) binary mixtures solution exceeded 95%; and the adsorption rate of immobilized bayberry tannin to Mo(VI) increased with the decline of initial concentration of Mo(VI) in multicomponent solution of Mo(VI)-Fe(III)-Mn(II)-Al(III) at 303K, the highest adsorption rate could reach at 97.6%, which assuredly indicated the adsorption selectivity of immobilized bayberry tannin to Mo(VI) was distinct, meanwhile, the adsorption rate ascended with the raise of temperature, it meant high temperature would profit for the selective adsorption of Mo(VI). In multicomponent solution of V(V)-Mg(II)-Fe(III)-Ni(II)-Cu(II)-Zn(II), with the decrease of initial concentration of V(V) when pH at 4.0, the adsorption rate of immobilized bayberry tannin to V(V) increase, with the highest rate could reach to 92%, which showed that the adsorption selectivity of the adsorbent to V(V) was remarkable, while temperature had little influence on adsorption selectivity. Meanwhile, the adsorption capacity of Mo(VI) and V(V) were remarkably higher than other metal ions in the mixed Ni(II)-Cu(II)-Fe(III)-Zn(II)-Mg(II)-Mo(VI)-V(V) solution, which indecated the adsorbent had a good selectivity to Mo(VI) and V(V), and it also showed high temperature would benefit the selectivity adsorption of Mo(VI) and V(V) as well. Hence, the immobilized bayberry tannin could be used in the selective adsorption of Mo(VI) and V(V) in multicomponent solution, and reached the motive of separation, purification and enrichment of the metals accordingly, which had practical worthiness.
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