Removal of contaminants of emerging concern by metal-organic framework nanoadsorbents: A review

Over the last two decades, various contaminants of emerging concern (CECs), such as endocrine disrupting compounds, along with pharmaceuticals and personal care products (PPCPs), have been of interest to the water industry because of their incomplete removal during the typical water and wastewater treatment processes. Recently, the potential environmental applications of metal-organic frameworks (MOFs) and MOF-based nanoadsorbents (MOF-NAs) have been widely studied. In particular, the use of these nanoadsorbents for CECs in water and wastewater treatment processes has been a rapidly growing area of interest in the recent literature due to their unique physicochemical properties. Therefore, it is necessary to understand the adsorption phenomena of various CECs by MOF-NAs, particularly because the physicochemical properties of various CECs create unique challenges for the removal of these compounds from water. In addition, the adsorption of CECs on MOF-NAs is significantly influenced by the physicochemical properties of the MOF-NAs and the water quality conditions. Therefore, this review provides a comprehensive assessment of recent studies on the removal of various CECs (e.g., analgesics, antibiotics, antiepileptics, antiseptics, and etc.) with different physicochemical properties by various MOF-NAs under various water quality conditions (e.g., pH, background ions/ionic strength, natural organic matter, and temperature). In addition, this review briefly discusses the recent literature on the synthesis of MOF-NAs, regeneration of MOF-NAs, and removal of CECs during water and wastewater treatment processes.