Removal of Mefenamic acid from aqueous solution with HKUST-1 sorbent using Uv-vis spectroscopy

Mefenamic acid (MEF) is one of the important type of non-steroidal anti-inflammatory drugs that their residues are continuously released into the aquatic environment through urban wastewater treatment plants (WWTP). For removal of such pollutants, adsorption is a generally efficient process that can be complementary to conventional treatment. Research of cheap, widely available adsorbents may make this process economically attractive. HKUST-1 Metal-organic framework (MOF) applied as an effective sorbent for removal of Mefenamic acid from aqueous solutions. It was synthesized by a simple, facile and environmentally friendly method and then charachterized by XRD and Ft-IR spectrometers. The absorption spectra of MEF in to HKUST-1 was recorded by Uv-vis spectrophotometer. Compared to the reported adsorbents, HKUST-1 has a very high adsorption rate, and it is found that MEF could be removed within 30 min. The adsorption Isoterm, kinetics and thermodynamic studies of MEF into HKUST-1 were investigated. The adsorption mechanism fallowed the Langmuir Isotherm and the maximum adsorption capacitance of HKUST-1 toward MEF was 110.47 mg.g-1. The Kinetic properties of the adsorption process were studied and results showed that adsorption mechanism correlated well with the pseudo-first-order model. Based on thermodynamic parameters such as ΔG, Δ H and ΔS confirm the adsorption process was spontaneous, exothermic and entropy-driven. The adsorption mechanism was proposed based on the effects of pH on adsorption and according to obtained results, both electrostatic and π- π interactions were probable for the adsorption of MEF by HKUST-1.These results indicated that HKUST-1 may be a promising sorbent in the removal of MEF from wastewater due to its high adsorption capacitance and fast removal ability.

Keywords:

Mefenamic acid , drug , HKUST-1 , Removal , Uv-vis Spectroscopy