Effective Removal of Humic Acid by Zr-MOFs with Surface Modification

Abstract

Humic acid (HA) in makeup water is one of the important safety issues of high−parameter power plants. Herein, the Zr−based metal organic frameworks (Zr−MOFs) were applied to remove humic acid in water. The mesoporous and active sites of Zr−MOFs were controlled by different ratios of ligands to increase the adsorption of HA. The maximum adsorption capacity was 150.15 mg g−1. The morphology and adsorption properties of the Zr−MOFs were characterized using scanning electron microscopy (SEM), X−ray diffraction (XRD), surface charge, Fourier Transform infrared (FT−IR), N2 adsorption−desorption and adsorption test. The adsorption process of HA accorded with the pseudo−second−order kinetics, while the adsorption isotherm conformed to the Langmuir model and the adsorption was proved to be a spontaneous and endothermic process. Physical adsorption by the mesoporous materials and the hydrogen bonding interactions between the Zr−MOFs and HA were the driving forces of HA adsorption. These results provided useful information for the effective removal of HA and enhanced our understanding of the adsorption mechanism of HA on Zr−MOFs.

Magnetic Metal–Organic Framework Enhanced Inorganic Coagulation for Water Purification

“…Moreover, it is important to extend the function of flocculants beyond just the acceleration of floc settling time. Metalorganic backbones (MOFs), characterized by porous structure, low density, high adsorption capacity, and high specific surface [29,30], have been widely used as drug carriers [31,32], sensors [33,34], catalysts [34,35], and hydrogen storage materials [36,37]. Despite their wide range of applications, many MOFs are still unstable in water, and few applications in water treatment have been reported [38].…”