Control of ZIF-62 and agZIF-62 Film Thickness within Asymmetric Tubular Supports through Pressure and Dose Time Variation of Atomic Layer Deposition.

Thin-films of metal-organic frameworks (MOFs) have widespread potential applications, especially with the emergence of glass-forming MOFs, which remove the inherent issue of grain boundaries and allow coherent amorphous films to be produced. Herein, it is established that atomic layer deposition (ALD) of zinc oxide lends excellent control over the thickness and localization of resultant polycrystalline and glass zeolitic imidazole framework-62 (ZIF-62) thin-films within tubular α-alumina supports. Through the reduction of the chamber pressure and dose times during zinc oxide deposition, the resultant ZIF-62 films are reduced from 38 µm to 16 µm, while the presence of sporadic ZIF-62 (previously forming as far as 280 µm into the support) is prevented. Furthermore, the glass transformation shows a secondary reduction in film thickness from 16 to 2 µm.

Novel easily separable core-shell Fe3O4/PVP/ZIF-8 nanostructure adsorbent: optimization of phosphorus removal from Fosfomycin pharmaceutical wastewater.

A new easily separable core-shell Fe3O4/PVP/ZIF-8 nanostructure adsorbent was synthesized and then examined for removal of Fosfomycin antibiotic from synthetic pharmaceutical wastewater. The removal process of Fosfomycin was expressed through testing the total phosphorus (TP). A response surface model (RSM) for Fosfomycin adsorption (as mg-P L-1) was used by carrying out the experiments using a central composite design. The adsorption model showed that Fosfomycin adsorption is directly proportional to core-shell Fe3O4/PVP/ZIF-8 nanostructure adsorbent dosage and time, and indirectly to initial Fosfomycin concentration. The removal increased by decreasing the pH to 2. The Fosfomycin removal was done at room temperature under an orbital agitation speed of 250 rpm. The adsorption capacity of core-shell Fe3O4/PVP/ZIF-8 nanostructure adsorbent reached around 1200 mg-P g-1, which is significantly higher than other MOF adsorbents reported in the literature. The maximum Langmuir adsorption capacity of the adsorbent for Fosfomycin was 126.58 mg g-1 and Fosfomycin adsorption behavior followed the Freundlich isotherm (R 2 = 0.9505) in the present study. The kinetics was best fitted by the pseudo-second-order model (R 2 = 0.9764). The RSM model was used for the adsorption process in different target modes.