ABSTRACT
The structure of polymeric catena-poly[2-amino-benzimidazolium [[dioxidovanadium(V)]-µ-oxido]], {(C7H8N3)2[V2O6]} n , has monoclinic symmetry. The title compound is of inter-est with respect to anti-cancer activity. In the crystal structure, infinite linear zigzag vanadate (V2O6)2- chains, constructed from corner-sharing VO4 tetra-hedra and that run parallel to the a axis, are present. Two different protonated 2-amino-benzimidazole mol-ecules are located between the (V2O6)2- chains and form classical N-Hâ¯O hydrogen bonds with the vanadate oxygen atoms, which contribute to the cohesion of the structure.
ABSTRACT
The organic-inorganic complex salt, (C8H10N3)3[La(NO3)6], comprises a network of N-protonated 2-amino-1-methyl-benzimidazolium cations and hexa-kis-(nitrato)lanthanate(III) anions. The LaIII atom is twelve-coordinate within a distorted icosa-hedral environment. In the unit cell, each pair of the LaIII atoms lie nearly on one of the crystallographic glide planes. In the crystal structure, there are several N-Hâ¯O hydrogen-bonding inter-actions between the cations and terminal oxygen atoms from the nitrate moieties of the [La(NO3)6]3- anion. Additional weak C-Hâ¯O hydrogen bonds between the cations and anions consolidate the three-dimensional arrangement of the structure. A packing analysis was performed to check the strength of the crystal packing.
ABSTRACT
The use of antiviral drugs has surged as a result of the COVID-19 pandemic, resulting in higher concentrations of these pharmaceuticals in wastewater. The degradation efficiency of antiviral drugs in wastewater treatment plants has been reported to be too low due to their hydrophilic nature, and an additional procedure is usually necessary to degrade them completely. Photocatalysis is regarded as one of the most effective processes to degrade antiviral drugs. The present study aims at synthesizing multiphase photocatalysts by a simple calcination of industrial waste from ammonium molybdate production (WU photocatalysts) and its combination with WO3 (WW photocatalysts). The X-ray diffraction (XRD) results confirm that the presence of multiple crystalline phases in the synthesized photocatalysts. UV-Vis diffuse reflectance spectra reveal that the synthesized multiphase photocatalysts absorb visible light up to 620 nm. Effects of calcination temperature of industrial waste (550-950 °C) and WO3 content (0-100%) on photocatalytic activity of multiphase photocatalysts (WU and WW) for efficient removal of SARS-CoV-2 antiviral drugs (lopinavir and ritonavir) in model and real wastewaters are studied. The highest k1 value is observed for the photocatalytic removal of ritonavir from model wastewater using WW4 (35.64 ×10-2 min-1). The multiphase photocatalysts exhibit 95% efficiency in the photocatalytic removal of ritonavir within 15 of visible light irradiation. In contrast, 60 min of visible light irradiation is necessary to achieve 95% efficiency in the photocatalytic removal of lopinavir. The ecotoxicity test using zebrafish (Danio rerio) embryos shows no toxicity for photocatalytically treated ritonavir-containing wastewater, and the contrary trend is observed for photocatalytically treated lopinavir-containing wastewater. The synthesized multiphase photocatalysts can be tested and applied for efficient degradation of other SARS-CoV-2 antiviral drugs in wastewater in the future.
