TY  - JOUR
A1  - Unuabonah, Emmanuel I.
A1  - El-Khaiary, Mohammad I.
A1  - Olu-Owolabi, Bamidele I.
A1  - Adebowale, Kayode O.
T1  - Predicting the dynamics and performance of a polymer-clay based composite in a fixed bed system for the removal of lead (II) ion
JF  - Chemical engineering research and design
N2  - A polymer-clay based composite adsorbent was prepared from locally obtained kaolinite clay and polyvinyl alcohol. The composite adsorbent was used to remove lead (II) ions from aqueous solution in a fixed bed mode. The increase in bed height and initial metal ion concentration increased the adsorption capacity of lead (II) and the volume of aqueous solution treated at 50% breakthrough. However, the adsorption capacity was reduced by almost 16.5% with the simultaneous presence of Ca2+/Pb2+ and Na+/Pb2+ in the aqueous solution. Regeneration of the adsorbent with 0.1 M of HCl also reduced its adsorption capacity to 75.1%. Adsorption of lead (II) ions onto the polymer-clay composite adsorbent in the presence of Na+ and Ca2+ electrolyte increased the rate of mass transfer, probably due to competition between cationic species in solution for adsorption sites. Regeneration further increased the rate of mass transfer as a result of reduced adsorption sites after the regeneration process. The length of the mass transfer zone was found to increase with increasing bed height but did not change with increasing the initial metal ion concentration. The models of Yoon-Nelson, Thomas, and Clark were found to give good fit to adsorption data. On the other hand, Bohart-Adams model was found to be a poor predictor for the column operation. The polymer-clay composite adsorbent has a good potential for the removal of lead (II) ions from highly polluted aqueous solutions.
KW  - Fixed bed
KW  - Adsorption models
KW  - Polymer-clay composite
KW  - Regeneration
KW  - Breakthrough
KW  - Mass transfer zone
Y1  - 2012
U6  - https://doi.org/10.1016/j.cherd.2011.11.009
SN  - 0263-8762
VL  - 90
IS  - 8
SP  - 1105
EP  - 1115
PB  - Inst. of Electr. and Electronics Engineers
CY  - Rugby
ER  - 
TY  - JOUR
A1  - Unuabonah, Emmanuel I.
A1  - Olu-Owolabi, Bamidele I.
A1  - Taubert, Andreas
A1  - Omolehin, Elizabeth B.
A1  - Adebowale, Kayode O.
T1  - SAPK a novel composite resin for water treatment with very high Zn2+, Cd2+, and Pb2+ adsorption capacity
JF  - Industrial & engineering chemistry research
N2  - A new sulfonated aniline-modified poly(vinyl alcohol)/K-feldspar (SAPK) composite was prepared. The cation-exchange capacity of the composite was found to be S times that of neat feldspar. The specific surface area and point of zero charge also changed significantly upon modification, from 15.6 +/- 0.1 m(2)/g and 2.20 (K-feldspar) to 73.6 +/- 0.3 m(2)/g and 1.91 (SAPK). Zn2+, Cd2+, and Pb2+ adsorption was found to be largely independent of pH, and the metal adsorption rate on SAPK was higher than that on neat feldspar. This particularly applies to the initial adsorption rates. The adsorption process involves both film and pore diffusion; film diffusion initially controls the adsorption. The Freundlich and Langmuir models were found to fit metal-ion adsorption on SAPK most accurately. Adsorption on neat feldspar was best fitted with a Langmuir model, indicating the formation of adsorbate monolayers. Both pure feldspar and SAPK showed better selectivity for Pb2+ than for Cd2+ or Zn2+.
Y1  - 2013
U6  - https://doi.org/10.1021/ie3024577
SN  - 0888-5885
VL  - 52
IS  - 2
SP  - 578
EP  - 585
PB  - American Chemical Society
CY  - Washington
ER  -