Uranium oxide catalysts: environmental applications for treatment of chlorinated organic waste from nuclear industry

Abstract

Huge amounts of nuclear waste, including depleted uranium, significantly contribute to the adverse environmental situation throughout the world. An approach to the effective use of uranium oxides in catalysts for the deep oxidation of chlorine-containing hydrocarbons is suggested. Investigation of the catalytic activity of the synthesized supported uranium oxide catalysts doped with Cr, Mn and Co transition metals in the chlorobenzene oxidation showed that these catalysts are comparable with conventional commercial ones. Physicochemical properties of the catalysts were studied by X-ray diffraction, temperature-programmed reduction with hydrogen (H-TPR), and Fourier transform infrared spectroscopy. The higher activity of Mn- and Co-containing uranium oxide catalysts in the H-TPR and oxidation of chlorobenzene in comparison with non-uranium catalysts may be related to the formation of a new disperse phase represented by uranates. The study of chlorobenzene adsorption revealed that the surface oxygen is involved in the catalytic process.

Chemistry of Actinide Centers in Heterogeneous Catalytic Transformations of Small Molecules

“…Whereas Taylor et al focused on uranium oxides and their applications in oxidation, − reduction, and steam forming reactions, Ismagilov reviewed solid-supported, uranium oxide composites and uranium-containing compounds for catalytic reactions in organic synthesis, − syngas production, , Fischer–Tropsch and hydrocracking processes, hydrodesulfurization, and oxidation and reduction reactions . Because of the thermal stability and resistance to catalytic poisons, such as sulfur, water, and chlorine, the application of uranium oxides for purification of waste gases polluting the environment was examined heavily in the past decades. , As the present Review mainly focuses on recent developments in small molecule activation using actinide containing compounds, several interesting publications and break-through observations on catalytic reactions such as the reduction of 4-nitrophenol using urania-palladium-graphene nanohybrids, the oxidation of chlorobenzene and benzyl alcohols, ,,,,− the degradation of Rhodamine B, or Suzuki–Miyaura cross-coupling reactions of aryl halides will not be reviewed herein. Instead, the focus is laid on the catalyst requirements and mechanistic studies on activations of the following small molecules: CO, H 2 O, H 2 O 2 , O 2 , CH 4 , and HCl (Table ).…”

Controlled Transformation of Liquid Metal Microspheres in Aqueous Solution Triggered by Growth of GaOOH

“…In addition, the melting point temperature of gallium-based alloys such as gallium indium alloy (EGaIn), gallium tin alloy (EGaSn), and gallium indium tin alloy (EGaInSn, Galinstan) can be regulated by changing the proportion of alloy components. These unique properties of gallium-based LMs make them have wide application potential in soft electronics, ,, flexible devices, , biological devices, , thermal management, , and nuclear industry. , …”

“…These unique properties of gallium-based LMs make them have wide application potential in soft electronics, 1,9,10 flexible devices, 11,12 biological devices, 13,14 thermal management, 15,16 and nuclear industry. 17,18 Gallium-based LMs are highly susceptible to oxidation when exposed to air, forming a dense thin film of gallium oxide, which prevents further oxidation of internal gallium 1,19 while reducing the surface tension, 20 thermal conductivity, and conductivity of LM. 21,22 However, a significant morphological change occurs when LM is dispersed in deionized (DI) water to form LM microspheres.…”

Influence of additives on low-temperature hydrothermal synthesis of UO2+x and ThO2

“…[40][41][42] There are also several reports on the catalytic reactions of acetaldehyde on uranium oxide surfaces. [43][44][45][46][47] In the absence of oxygen, UO 3 was converted to UO 2 through a reaction with acetaldehyde. 43 We aim to investigate the effect of the reductive function of acetaldehyde on the conditions for dioxide formation in the hydrothermal synthesis of uranium oxides.…”