Efficient removal of As(V) from simulated arsenic-contaminated wastewater via a novel metal-organic framework material: Synthesis, structure, and response surface methodology

A novel metal-organic framework material {[N(C2H5)(3)][Zn-2(ptmda)(2)(mu(2)-H2O)]center dot(H2O)(0.5)}(n) {GUT-3; H(2)ptmda is 4,4 '-([p-tolylazanediyl]bis [methylene])dibenzoic acid} was successfully synthesized using the hydrothermal method and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. GUT-3 has a two-dimensional network based on dinuclear [Zn-2(ptmda)(2)(mu(2)-H2O)](-) building units which formed an eightfold interpenetration network in GUT-3 molecules. Hirshfeld surface analysis revealed that H-H, C-H, and O-H bonds accounted for the majority of intermolecular interactions. Moreover, the interactions between GUT-3 and As(V) - the form of As(V) is AsO43- - were analyzed in aqueous solutions in a batch system to study the effect of pH, concentration, adsorbent dose, adsorption time, adsorption temperature, and shaking speed. The kinetic and isotherm data of arsenic adsorption on GUT-3 were accurately modeled by pseudo-second-order, Langmuir (q(m) = 33.91 mg/g), and Freundlich models. The Box-Behnken response surface method was used to optimize the adsorption conditions of As(V) from the simulated arsenic-contaminated wastewater. The effect of various experimental parameters and optimal experimental conditions was ascertained using the quadratic model.