Investigation of metal organic frameworks for the adsorptive removal of hydrochloride from dilute aqueous solution

In this paper, six kinds of reported water-stable MOFs, MIL-101(Cr), MIL-100(Cr, Fe), UiO-66, MIL-96(Al), and MIL-53(Cr) were evaluated as adsorbents for removal of hydrochloride from dilute aqueous solution. The as-synthesized products were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The results showed that UiO-66 exhibited excellent stability towards hydrochloride and the highest adsorption capacity among the six studied MOFs. Further researches on kinetics, thermodynamics, isotherms of adsorption process of hydrochloride on UiO-66 and its stability towards acid were investigated in detail. Moreover, a simple method was developed to free hydrochloride and recycle UiO-66 for repeated adsorption process, which showed UiO-66 may work as a good adsorbent for removal of hydrochloride from dilute aqueous solution.