TY - JOUR
T1 - Improved removal capacity and equilibrium time of maghemite nanoparticles growth in zeolite type 5a for pb(Ii) adsorption
AU - Ramos-Guivar, Juan A.
AU - Taipe, Katterine
AU - Schettino, Miguel Angelo
AU - Silva, Eloi
AU - Torres, Marco Antonio Morales
AU - Passamani, Edson Caetano
AU - Litterst, Fred Jochen
N1 - Publisher Copyright:
© 2020 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2020/9
Y1 - 2020/9
N2 - Novel magnetic zeolite type 5A nanocomposites were synthesized by the co-precipitation method and applied to lead removal from aqueous ambient. Maghemite nanoparticles were mixed with zeolite and, by controlling its content, transmission electron microscopy results gave sizes of 5 to 15 nm and selected area electron diffraction patterns confirmed the presence of zeolite. The nanocomposites have high specific surface area with values up to 194 m2/g. Magnetization measurements proved superparamagnetic behavior with saturation values of ~35 emu/gFe. Kinetic adsorption experiments showed removal efficiencies of 99.9% and an enhanced equilibrium time of 5 min. The lead concentrations after adsorption experiments lay under the permissible levels of 10 µg L−1, according to the World Health Organization. The maximum adsorption capacity, estimated by Sips model, was 265 mg L−1 at 300 K. The removal efficiency was significantly improved in the range of pH > 6, as well as in the presence of cation interferents such as Ca(II), Cu(II), and Cd(II). The adsorption mechanism was explained with cation exchange between Pb(II), the zeolite framework, and the protonated maghemite surface. Besides, our system revealed recyclability even after seven regeneration cycles. Thus, our synthesized materials have remarkable adsorption properties for lead water remediation processes.
AB - Novel magnetic zeolite type 5A nanocomposites were synthesized by the co-precipitation method and applied to lead removal from aqueous ambient. Maghemite nanoparticles were mixed with zeolite and, by controlling its content, transmission electron microscopy results gave sizes of 5 to 15 nm and selected area electron diffraction patterns confirmed the presence of zeolite. The nanocomposites have high specific surface area with values up to 194 m2/g. Magnetization measurements proved superparamagnetic behavior with saturation values of ~35 emu/gFe. Kinetic adsorption experiments showed removal efficiencies of 99.9% and an enhanced equilibrium time of 5 min. The lead concentrations after adsorption experiments lay under the permissible levels of 10 µg L−1, according to the World Health Organization. The maximum adsorption capacity, estimated by Sips model, was 265 mg L−1 at 300 K. The removal efficiency was significantly improved in the range of pH > 6, as well as in the presence of cation interferents such as Ca(II), Cu(II), and Cd(II). The adsorption mechanism was explained with cation exchange between Pb(II), the zeolite framework, and the protonated maghemite surface. Besides, our system revealed recyclability even after seven regeneration cycles. Thus, our synthesized materials have remarkable adsorption properties for lead water remediation processes.
KW - Lead removal
KW - Maghemite
KW - Water treatment
KW - Zeolite type 5A
UR - http://www.scopus.com/inward/record.url?scp=85093879422&partnerID=8YFLogxK
U2 - 10.3390/nano10091668
DO - 10.3390/nano10091668
M3 - Artículo
AN - SCOPUS:85093879422
SN - 2079-4991
VL - 10
SP - 1
EP - 19
JO - Nanomaterials
JF - Nanomaterials
IS - 9
M1 - 1668
ER -