In this study, three different magnetic core–shell Fe3O4@LDHs
composites were developed by a rapid coprecipitation method
for phosphate adsorption. The samples were characterized
by TEM, FTIR, XRD, VSM, BET and zeta potential analyses.
Characterization results proved the successful synthesis of core–
shell Fe3O4@LDHs composites. Adsorption experiments were carried
out as a function of adsorbent dosage, contact time and initial
pH of phosphate solution. The removal ratio of phosphate tended
to decrease with the increase of solution pH. Mechanisms for phosphate
adsorption onto Fe3O4@LDHs composites at different initial
solution pH were also proposed in this study. The adsorption of
phosphate could reach equilibrium quickly at about 60 min and
the pseudo-second-order kinetic model accurately described the
phosphate adsorption kinetics by Fe3O4@LDHs. The sign of adsorption
acceleration in the first and second regions was negative and
initial adsorption velocity increased with increasing time by
KASRA model. The adsorption isotherm data agreed well with
Langmuir model. The adsorption curves showed a three-region
behavior in the ARIAN model. Adsorption thermodynamic showed
that the adsorption process was endothermic and spontaneous in
nature. In addition, the phosphate adsorption capacity followed
the order of Fe3O4@Zn–Al–LDH > Fe3O4@Mg–Al–LDH > Fe3O4@
Ni–Al–LDH. Furthermore, the magnetic composites were easily
separated by the external magnetic field in 10 s. With further
development, the core–shell Fe3O4@LDHs composites may offer a
simple and effective single step treatment option to treat phosphate
contaminated water without the pre-/post-treatment
requirement for current industrial practice.
In this study, three different magnetic core–shell Fe3O4@LDHscomposites were developed by a rapid coprecipitation methodfor phosphate adsorption. The samples were characterizedby TEM, FTIR, XRD, VSM, BET and zeta potential analyses.Characterization results proved the successful synthesis of core–shell Fe3O4@LDHs composites. Adsorption experiments were carriedout as a function of adsorbent dosage, contact time and initialpH of phosphate solution. The removal ratio of phosphate tendedto decrease with the increase of solution pH. Mechanisms for phosphateadsorption onto Fe3O4@LDHs composites at different initialsolution pH were also proposed in this study. The adsorption ofphosphate could reach equilibrium quickly at about 60 min andthe pseudo-second-order kinetic model accurately described thephosphate adsorption kinetics by Fe3O4@LDHs. The sign of adsorptionacceleration in the first and second regions was negative andinitial adsorption velocity increased with increasing time byKASRA model. The adsorption isotherm data agreed well withLangmuir model. The adsorption curves showed a three-regionbehavior in the ARIAN model. Adsorption thermodynamic showedthat the adsorption process was endothermic and spontaneous innature. In addition, the phosphate adsorption capacity followedthe order of Fe3O4@Zn–Al–LDH > Fe3O4@Mg–Al–LDH > Fe3O4@Ni–Al–LDH. Furthermore, the magnetic composites were easilyseparated by the external magnetic field in 10 s. With further
development, the core–shell Fe3O4@LDHs composites may offer a
simple and effective single step treatment option to treat phosphate
contaminated water without the pre-/post-treatment
requirement for current industrial practice.
การแปล กรุณารอสักครู่..