TY - JOUR
T1 - Sorption properties of the activated carbon-zeolite composite prepared from coal fly ash for Ni2+, Cu2+, Cd2+ and Pb2+
AU - Jha, Vinay Kumar
AU - Matsuda, Motohide
AU - Miyake, Michihiro
N1 - Funding Information:
This work was supported by a Grant-in-Aid from Okayama Prefectural Government and Okayama Prefecture Industrial Promotion Foundation, and in part by a Grant-in-Aid from the Okayama University 21st Century COE program “Strategic Solid Waste Management for Sustainable Society”. We are thankful to Professor Dr. K.J.D. MacKenzie of Victoria University of Wellington, Wellington, New Zealand for critical reading and editing of the manuscript.
PY - 2008/12/15
Y1 - 2008/12/15
N2 - Composite materials of activated carbon and zeolite have been prepared successfully by activating coal fly ash (CFA) by fusion with NaOH at 750 °C in N2 followed by hydrothermal treatments under various conditions. Uptake experiments for Ni2+, Cu2+, Cd2+ and Pb2+ were performed with the materials thus obtained from CFA. Of the various composite materials, that were obtained by hydrothermal treatment with NaOH solution (ca. 4 M) at 80 °C (a composite of activated carbon and zeolite X/faujasite) proved to be the most suitable for the uptake of toxic metal ions. The relative selectivity of the present sorbents for the various ions was Pb2+ > Cu2+ > Cd2+ > Ni2+, with equilibrium uptake capacities of 2.65, 1.72, 1.44 and 1.20 mmol/g, respectively. The sorption isotherm was a good fit to the Langmuir isotherm and the sorption is thought to progress mainly by ion exchange with Na+. The overall reaction is pseudo-second order with rate constants of 0.14, 0.17, 0.21 and 0.20 L g/mmol min for the uptake of Pb2+, Cu2+, Cd2+ and Ni2+, respectively.
AB - Composite materials of activated carbon and zeolite have been prepared successfully by activating coal fly ash (CFA) by fusion with NaOH at 750 °C in N2 followed by hydrothermal treatments under various conditions. Uptake experiments for Ni2+, Cu2+, Cd2+ and Pb2+ were performed with the materials thus obtained from CFA. Of the various composite materials, that were obtained by hydrothermal treatment with NaOH solution (ca. 4 M) at 80 °C (a composite of activated carbon and zeolite X/faujasite) proved to be the most suitable for the uptake of toxic metal ions. The relative selectivity of the present sorbents for the various ions was Pb2+ > Cu2+ > Cd2+ > Ni2+, with equilibrium uptake capacities of 2.65, 1.72, 1.44 and 1.20 mmol/g, respectively. The sorption isotherm was a good fit to the Langmuir isotherm and the sorption is thought to progress mainly by ion exchange with Na+. The overall reaction is pseudo-second order with rate constants of 0.14, 0.17, 0.21 and 0.20 L g/mmol min for the uptake of Pb2+, Cu2+, Cd2+ and Ni2+, respectively.
KW - Coal fly ash
KW - Composite materials
KW - Retention of metals
KW - Toxic metal ions
KW - Zeolite
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U2 - 10.1016/j.jhazmat.2008.02.107
DO - 10.1016/j.jhazmat.2008.02.107
M3 - Article
C2 - 18417279
AN - SCOPUS:54049111030
SN - 0304-3894
VL - 160
SP - 148
EP - 153
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
IS - 1
ER -