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Nitrate-intercalated Mg Al layered double hydroxide (LDH) was successfully delaminated in water by a facile and effective method upon reflux at 120 °C for 24 h followed by sonication at 40 °C for 5 h. This process is environmentally friendly since water is the only solvent used. The delaminated nanosheets were characterized by microscopic, spectroscopic, and particle size analyses. The delamination process successfully produced octahedron-shaped single-layer nanosheets 50–150 nm in size. X-ray photoelectron spectroscopy (XPS) data confirmed that the surface elements and their chemical status are consistent with the basic layer of Mg Al LDH. The delaminated nanosheets displayed higher adsorption capacity for removing heavy metals from waste water than the original powdered LDH. After treating the waste water, a sharp and intense peak in the X-ray powder diffraction (XRD) pattern of the precipitate confirms the restacking of the LDH nanosheets. [ABSTRACT FROM AUTHOR]

Abstract: Although effective treatments of SO x are essential for preventing air pollution, current methods pose other environmental problems such as increased amounts of desulfurized gypsum and reduced landfill lifetimes. We report a process for removing SO2 from waste streams using a Mg−Al oxide slurry. The ability of the mixed oxide to remove SO2 increased with slurry quantity and temperature but decreased with time. SO2 was removed through the reconstruction of a Mg−Al layered double hydroxide (Mg−Al LDH) intercalated with , which was derived from the dissociation of H2SO3 upon dissolution of SO2 in the slurry. SO2 was not adsorbed onto the surface of the Mg−Al oxide. These results suggest that SO2 removal using a Mg−Al oxide slurry may be possible without the concomitant problems of conventional treatment methods. [Copyright &y& Elsevier]

Nitrate-intercalated MgAl layered double hydroxide (LDH) was successfully delaminated in water by a facile and effective method upon reflux at 120 °C for 24 h followed by sonication at 40 °C for 5 h. This process is environmentally friendly since water is the only solvent used. The delaminated nanosheets were characterized by microscopic, spectroscopic, and particle size analyses. The delamination process successfully produced octahedron-shaped single-layer nanosheets 50-150 nm in size. X-ray photoelectron spectroscopy (XPS) data confirmed that the surface elements and their chemical status are consistent with the basic layer of MgAl LDH. The delaminated nanosheets displayed higher adsorption capacity for removing heavy metals from waste water than the original powdered LDH. After treating the waste water, a sharp and intense peak in the X-ray powder diffraction (XRD) pattern of the precipitate confirms the restacking of the LDH nanosheets., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The treatment of cesium-contaminated wastewater has become one of the biggest issues. The selective Cs + removal from wastewater containing competitive alkali metal ions such as Na + is desired to reduce the volume of sludge. Therefore, the present work focused on water-soluble calix[4]arene-bis-crown-6 (W-BisC6) to selectively capture Cs + . For characterization of the complex, UV-vis spectroscopy is commonly used, however, due to the limited availability of information it can be hard to quickly identify the specific structures of some complexes. In this work, the electrospray ionization time of flight spectrometry (ESI-TOF-MS) is successfully utilized to identify the number and type of cations in W-BisC6-cation complexes. ESI-TOF-MS accurately recognized 4 types of complex (W-BisC6-Na + , W-BisC6-Cs + , W-BisC6-2Na + , W-BisC6-Na + -Cs + ), and the experimental and simulated results were almost perfectly matched. It also revealed the difficulty of W-BisC6-2Cs + complex formation under the present conditions. Thus, this technique is significantly helpful for rapid identification of the specific structures of complexes during Cs + -contaminated wastewater treatment., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Although effective treatments of SO(x) are essential for preventing air pollution, current methods pose other environmental problems such as increased amounts of desulfurized gypsum and reduced landfill lifetimes. We report a process for removing SO(2) from waste streams using a Mg-Al oxide slurry. The ability of the mixed oxide to remove SO(2) increased with slurry quantity and temperature but decreased with time. SO(2) was removed through the reconstruction of a Mg-Al layered double hydroxide (Mg-Al LDH) intercalated with SO(3)(2-), which was derived from the dissociation of H(2)SO(3) upon dissolution of SO(2) in the slurry. SO(2) was not adsorbed onto the surface of the Mg-Al oxide. These results suggest that SO(2) removal using a Mg-Al oxide slurry may be possible without the concomitant problems of conventional treatment methods., (Copyright © 2012 Elsevier Ltd. All rights reserved.)