In this paper, the catalytic wet peroxide oxidation (CWPO) combined with vacuum ultraviolet (VUV) irradiation was developed to mineralize the wastewater with high concentration of unsymmetrical dimethylhydrazine (UDMH), especially to decompose the main byproduct of UDMH decomposition, N-nitrosodimethylamine (NDMA). CuO-NiO-MgO/γ-AlO was used as the catalyst and HO as the resources of . Fourier Transform Infrared spectroscopy (FT-IR), X-ray Powder Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray spectroscopy (EDX) were employed to evaluate the structure of the catalyst. The treatment performances such as the UDMH degradation efficiency, chemical oxygen demand (COD) removal efficiency, and the concentration of N-nitrosodimethylamine (NDMA) were investigated in the treating process. The optimal conditions were obtained based on the results of single-factor experiments including parameters such as the initial UDMH concentration, catalyst dosage, initial pH, HO dosage and temperature. The comprehensive results indicated that CWPO/HO/VUV process presented remarkable treatment performance to the reaction conditions with about 100% UDMH conversion efficiency, 95.02% COD removal efficiency and approximately 100% UDMH removal within 30 min.
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http://dx.doi.org/10.1080/09593330.2019.1635213 | DOI Listing |
J Sep Sci
August 2024
Laboratory of Environmental Analytical Chemistry, Core Facility Center 'Arktika', Northern (Arctic) Federal University, Arkhangelsk, Russia.
Unsymmetrical dimethylhydrazine (UDMH) based rocket fuel, when released into the soil, undergoes oxidative transformations to form a variety of toxic nitrogen-containing products (TPs). Loamy soils containing aluminosilicates (clay) are capable of strong binding and retention of UDMH TPs due to a combination of polar sorption and cation-exchange properties, posing challenges for their extraction and quantification. To overcome this problem, the present study proposes direct thermal desorption (TD) of analytes from loam facilitated by the addition of modifiers competing with UDMH TPs for sorption centers and ensuring their conversion into molecular form.
View Article and Find Full Text PDFOn October 11, 2018, in the Ulytau region of the Republic of Kazakhstan, the Soyuz-FG launch vehicle carrying a crewed MS-10 spacecraft failed, creating two areas where rocket propellants spilled and soil condition was monitored in 2018, 2019, 2022 and 2023. This article presents data on the content of pollutants, namely unsymmetrical dimethylhydrazine (UDMH), nitrosodimethylamine (NDMA) and total petroleum hydrocarbons (TPH), total N, organic carbon, exchangeable Ca and Mg, water-soluble NO-, NO-, HCO-, CO , SO , Cl, , Na, pH values, cation exchange capacity and electrical conductivity of the water extract in disturbed and background Aridisols (more than 200 samples in total). This data set contains information on interseasonal (autumn 2022 and spring 2023) differences in the content and vertical differentiation of some soil properties in Aridisols in Central Kazakhstan.
View Article and Find Full Text PDFChemosphere
August 2024
Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia. Electronic address:
Thirty two commercially available standards were used to determine chromatographic retention indices for three different stationary phases (non-polar, polar and mid-polar) commonly used in gas chromatography. The selected compounds were nitrogen-containing heterocycles and amides, which are referred to in the literature as unsymmetrical dimethylhydrazine (UDMH) transformation products or its assumed transformation products. UDMH is a highly toxic compound widely used in the space industry.
View Article and Find Full Text PDFJ Hazard Mater
July 2024
State Key Laboratory of Integrated Optoelectronics, Key Laboratory of Advanced Gas Sensors, Jilin Province, College of Electronic Science and Engineering, International Center of Future Science, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
J Environ Manage
April 2024
School of Light Industry and Chemical Engineering, Dalian Polytechnic University, No. 1 Qinggongyuan, Ganjinzi District, Dalian, 116034, PR China. Electronic address:
The main challenge facing the anodic electro-Fenton through the 2e water oxidation reaction (WOR) for toxics degradation lies in the electrode's stability, because the anodic oxygen evolution (OER) generated O will inevitably exfoliate the electro-active components loaded on the electrode substrate. To address this point, two aspects need attention: 1) Identifying a catalyst that exhibits both excellent electrocatalytic activity and selectivity can improve the faradaic efficiency of hydrogen peroxide (HO); 2) Employing novel methods for fabricating highly stable electrodes, where active sites can be firmly coated. Consequently, this study utilized microarc oxidation (MAO) to prepare a ceramic film electrode ZnSnO@Ti at 300 V.
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