Adsorption of Pb(II) and Cu(II) ions from aqueous solution by an electrospun CeO2 nanofiber adsorbent functionalized with mercapto groups

A novel PVP/CeO2/TMPTMS nanofiber adsorbent was prepared by the electrospinning method. The prepared nanofibers were characterized by scanning electron microscope (SEM), BrunauerEmmertTeller (BET), Fourier transform infrared (FTIR) and BrrettJoynerHalenda (BJH) analysis. The results showed that surface area of PVP/CeO2/TMPTMS/P123 is almost five times greater than PVP/CeO2/TMPTMS nanofiber adsorbent. Batch experiments were carried out as a function of solution pH, contact time, initial concentration and temperature. The kinetic data of Pb(II) and Cu(II) ions were well described by the double-exponential model. The maximum adsorption capacities of PVP/CeO2/TMPTMS nanofiber by applying the Langmuir equation were found to be 0.439 mmol/g (90.9 mg/g) for Pb(II) and 1.390 mmol/g (88.3 mg/g) for Cu(II) ions. qm of PVP/CeO2/TMPTMS/P123 nanofiber was found to be 1.315 mmol/g (272.3 mg/g) for Pb(II) and 4.145 mmol/g (263.4 mg/g) for Cu(II) ions. Thermodynamic studies showed that adsorption process was favored at higher temperature. The adsorbent can be easily regenerated with desorbing agent of 0.1 M HNO3. The inhibitory effect of competitive Cu(II) ion on the Pb(II) adsorption was greater than the inhibitory effect of competitive Pb(II) ion on the Cu(II) adsorption in the binary systems and the adsorption affinity of the tested metals is Cu(II) > Pb(II). (C) 2015 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.