Abstract:
UiO-66(Zr) metal organic frame work was successfully synthesized by solvothermal method. The
as synthesized UiO-66(Zr) was characterized using FTIR, XRD, TGA and SEM techniques to
investigate the functional group, structural crystallinity, thermal stability and morphology of the
material, respectively. Adsorptive removal of Malathion and 2, 4-D with UiO-66(Zr) were
studied to understand its applicability in the removal of pesticides from contaminated water.
According to the outcome of this study, UiO-66(Zr) exhibited fast adsorption capacity (t, one
hour) and importantly the adsorption of both pesticides over UiO-66(Zr) were favorable at low
concentrations. The high adsorption capacity of UiO-66(Zr) may be attributed to its high
porosity, smaller particle sizes and high crystalline nature. The effects of different experimental
parameters, namely, pH, adsorbent dose, contact time, speed of agitation and initial pesticides
concentration were studied by using batch experiment. The adsorption isotherm experiment
showed that the equilibrium data were fitted to the Freundlich model. The kinetic study
demonstrated that pseudo-second-order model gave a best fitting to the adsorption of Malathion
and 2, 4-D on the (UiO-66) adsorbent. The thermodynamic parameters were calculated and the
results show that the adsorption of Malathion and 2,4-D on the adsorbent is a spontaneous
and exothermic process. To evaluate the matrix effect on adsorption performance of UiO66(Zr),
real sample, (tap water) were spiked and its recovery were evaluated. The results revealed that the recovery values were satisfactory (found to be in the range of (70-120%), and it
can be said that the matrix effect from the water samples on the adsorption of Malathion and 2,
4-D on to UiO-66(Zr) was not affect their adsorption. Therefore, UiO-66(Zr) is the promising
adsorbent for the removal of pesticides in waste water.
