The effect of crosslinking on the adsorption behavior of copper (II) onto poly(2-hydroxy-4-acryloyloxybenzophenone)

摘要

The adsorption behavior of Cu(II) ions onto poly(2-hydroxy-4- acryloyloxybenzophenone), polymer I, and onto poly(2-hydroxy-4- acryloyloxybenzophenone) crosslinked with different amounts of divinylbenzene (DVB), polymers II, III, and IV, in aqueous solutions was investigated using batch adsorption experiments as a function of contact time, pH, and temperature. The amount of metal ion uptake of the polymers was determined by using atomic absorption spectrometry (AAS) and the highest uptake was achieved at pH 7.0 and by using perchlorate as an ionic strength adjuster for polymers I, II, III, and IV. Results revealed that the adsorption capacity (q _e and Q _m) of Cu(II) ions decreases with increasing crosslinking due to the decrease of chelation sites. In addition, the rate of adsorption (k _2) of Cu(II) ions decreases with the increase of crosslinking because it becomes more difficult for Cu(II) ions to diffuse into the chelation sites. The isothermal behavior and the kinetics of adsorption of Cu(II) ions on these polymers with respect to the initial mass of the polymer and temperature were also investigated. The experimental data of the adsorption process was found to correlate well with the Langmuir isotherm model.