In this study, we report the application of magnetic metal-organic frameworks as a novel adsorbent for fast removal of Pb(II) ions from aqueous solution in view of adsorption isotherms, kinetics, thermodynamics, desorption, and adsorbent regeneration. The adsorbent was characterized by PPMS, XRD, TEM and N2 adsorption/desorption measurement. The adsorption follows pseudo-second-order kinetics model and fits the Freundlich adsorption model with the adsorption capacity of 612 mg g–1 for Pb(II) ions. It is a spontaneous and endothermic process controlled by positive entropy change. The used Fe3O4/HKUST-1 could be regenerated effectively and recycled at least four times without significant loss of adsorption capacity.
Nowadays, there has been an enormous demand for chemical sensors to detect a variety of analytes for a range of applications, including homeland security guarding, exploration of mineral resources, meteorological observation and telemetry, industrial automation, agricultural fresh preservation, environment monitoring and food quality controlling. Metal-organic frameworks are a new class of porous materials, which are formed by the assembly of metal ions with functional organic ligands. They have attracted great attention in chemical sensing owing to their suitable porosity, specific functional groups, higher quantum yield and tunable luminescent properties. This review summarizes some examples of the application of luminescent metal-organic frameworks for sensing of nitro explosives, metal ions, small molecules, pH value and temperature.
Removal of mercury contaminants from nature receives a global attention from a biological and environmental standpoint. Recently, metal-organic frameworks (MOFs) show much promises in the adsorptive removal of mercury species. This review summarizes the recent studies on the MOF-based materials for mercury sensing and removal. The design of those materials are listed in five categories—use of unfunctionalized MOFs, linker design of MOFs, modification of MOF system, post-synthetic modification of the frameworks, and development of MOF-based composites. Finally, several key learning points are discussed in the aim of a facilitating new design of MOF-based sensors and adsorbents for mercury.