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  - 
TY  - JOUR
A1  - Unuabonah, Emmanuel I.
A1  - Günter, Christina
A1  - Weber, Jens
A1  - Lubahn, Susanne
A1  - Taubert, Andreas
T1  - Hybrid Clay - a new highly efficient adsorbent for water treatment
JF  - ACS sustainable chemistry & engineering
N2  - New hybrid clay adsorbent based on kaolinite clay and Carica papaya seeds with improved cation exchange capacity (CEC), rate of heavy metal ion uptake, and adsorption capacity for heavy metal ions were prepared. The CEC of the new material is ca. 75 meq/100 g in spite of the unexpectedly low surface area (approximate to 19 m(2)/g). Accordingly, the average particle size of the hybrid clay adsorbent decreased from over 200 to 100 pm. The hybrid clay adsorbent is a highly efficient adsorbent for heavy metals. With an initial metal concentration of 1 mg/L, the hybrid clay adsorbent reduces the Cd2+, Ni2+, and Pb2+ concentration in aqueous solution to <= 4, <= 7 and <= 20 mu g/L, respectively, from the first minute to over 300 min using a fixed bed containing 2 g of adsorbent and a flow rate of approximate to 7 mL/min. These values are (with the exception of Pb2+) in line with the WHO permissible limits for heavy metal ions. In a cocktail solution of Cd2+, and Ni2+, the hybrid clay shows a reduced rate of uptake but an increased adsorption capacity. The CEC data suggest that the adsorption of Pb2+, Cd2+, and Ni2+ on the hybrid clay adsorbent is essentially due to ion exchange. This hybrid clay adsorbent is prepared from materials that are abundant and by a simple means that is sustainable, easily recovered from aqueous solution, nonbiodegradable (unlike numerous biosorbent), and easily regenerated and is a highly efficient alternative to activated carbon for water treatment.
KW  - Kaolinite
KW  - Hybrid clay
KW  - Water treatment
KW  - Cation exchange Capacity
KW  - Adsorbent
KW  - Kinetics
Y1  - 2013
U6  - https://doi.org/10.1021/sc400051y
SN  - 2168-0485
VL  - 1
IS  - 8
SP  - 966
EP  - 973
PB  - American Chemical Society
CY  - Washington
ER  -