Acid-promoted Synthesis of MWCNT/UiO-66-NH2 Nanocomposite for Highly Efficient Removal of Ketoprofen

A novel MWCNT/UiO-66-NH2 nanocomposite with high porosity and water stability was fabricated through a facile acid-promoted method, which has high adsorption efficiency for ketoprofen (KET) from aqueous solutions. The nanomaterials were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller theory (BET), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR), transmiassion electron microscopy (TEM) and Zeta potentials to study their structures and functionalities. The as-developed MWCNT/UiO-66-NH2 nanocomposite exhibited excellent adsorption efficiency (over 93% for 40 mg/L ketoprofen) by combining multi-walled carbon nanotubes (MWCNT) with amination of zirconium-based metal organic frameworks (UiO-66-NH2). The adsorption capacity of MWCNT/UiO-66-NH2 was observed to reach up to 233 mg/g for KET. The improved adsorption capacity of MWCNT/UiO-66-NH2 was due to the anchoring technology, which prevented the aggregation of UiO-66-NH2 nanoparticles and increased the effective adsorption surface of the MWCNT/UiO-66-NH2 nanocomposite. The main factors affecting the adsorption process such as time, pH and ionic strength were investigated in detail. Besides, MWCNT/UiO-66-NH2 nanocomposite could be reproduced without significant degradation by means of simple ethanol washing and reused for continuous adsorption. Herein, MWCNT/UiO-66-NH2 nanocomposite showed great potential for effective removal of ketoprofen from water.