Abstract:
Various industries like textile, plastic, pulp, and paper produce dye-containing wastewaters that
have harmful effects on the environment as well as human health. For this purpose UiO-66 (ZrMOF),
adsorbent was prepared to remove dyes from aqueous solution. The aim of this study was
to investigate the capacity of UiO-66(Zr-MOF) in the removal of dyes, methyl orange (MO) and
methylene blue (MB), from aqueous solutions. The adsorbent was synthesized by solvothermal
method at high temperature condition. The as synthesized UiO-66(Zr-MOF) was characterized
using XRD technique thereby ensuring their structural crystallinity. The thermal stabilities of the
UiO-66(Zr-MOF) was studied using the TG/DTA technique. The results indicated that UiO66(Zr-MOF)
showed a high adsorption capacity which may possibly arise from its high porosity,
smaller particle sizes and high crystalline nature. Adsorption study was carried out by batch
experiment. The effects of different experimental parameters, namely, solution pH, adsorbent
dose, contact time, speed of agitation and initial dyes concentration were determined. The
isotherm experiment showed that equilibrium data were well fitted to the Freundlich model. The
kinetic study demonstrating the pseudo-second-order model gave a best fitting to the adsorption
of dyes on the adsorbent. The thermodynamic parameters were calculated and the results show
that the adsorption of dyes on the adsorbent is a spontaneous and endothermic process. The
regeneration of dye saturated UiO-66(Zr-MOF) was investigated by using deionized water
solution and the result revealed that, UiO-66(Zr-MOF) can be easily regenerated and re-used several times, indicating that this adsorbent could have great potential for the dye adsorption of
wastewater.
