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In the mid 20th century, type OMTI fire-resistant oil (fire-resistant oil of the thermal engineering institute), whose production technology was developed by specialists of the All-Russian Thermal Engineering Institute (VTI), received wide use at Russian and also at some foreign power plants. Type OMTI oil is distinguished by its high fire-resistant qualities, good lubrication properties, high thermal oxidation and hydrolytic stability, and long service life. Its drawback, as of any phosphorus esters, is sensitivity to the presence of water and increased temperatures, the action of which destructs the fluid with generation of acidic products. This process is "autocatalytic" in nature with a rather quickly reached unacceptable acidic level, at which the replacement of oil may be required. Nowadays, in view of the fact that fire-resistant oils are widely used but have a high cost, matters concerned with supporting the operation of fire-resistant oils and also extending their service life are becoming of much relevance. Another important issue is searching for efficient methods to restore the qualitative characteristics of spent oils that have been accumulated at power industry enterprises with the aim of repeatedly using them as hydraulic fluid or raw material for obtaining new oil. For extending the service life of operating oils and restoring spent oils to the required characteristics, oil purification plants, in which the fluids are subjected to sorption purification and acid destruction products are removed, are required. To ensure the effectiveness of the implemented processes, the sorbent must comply with certain criteria. It should be noted that stable operation of the power industry is essential for the energy security of the state; therefore, it is necessary to commence work on developing the compositions of a new type of fire-resistant oils on the basis of tert-butylphenyls and also elaborating the technology for manufacturing them and estimating the possibility to implement the process at existing industrial chemical sites. The manufacture of the new type of oils must be accompanied by the development of corresponding regulatory documents. [ABSTRACT FROM AUTHOR]

Dysprosium oxychloride, DyOCl, was synthesized using a simple hydrolysis method with DyCl3·6H2O. X-ray powder diffraction (XRD) data was used to determine the crystal structure. The DyOCl compound is isostructural to the matlockite (PbFCl) crystal structure and crystallizes in the tetragonal P4/nmm (#129) space group. The crystal structure contains the alternating cationic layers of (DyO)n and anionic layers of nCl− along the c-axis. The structural data including unit cell, volume, and density of DyOCl were compared to other rare-earth oxychloride data from the Inorganic Crystal Structure Database (ICSD) and our previous study on TbOCl. Fourier-transform infrared spectroscopy was performed on DyOCl and peaks observed at 543 and 744 cm−1 were attributed to Dy–O and Dy–Cl. Scanning electron microscopy analysis showed irregularly shaped crystals. Hot-stage XRD, thermogravimetry, as well as differential scanning calorimetry coupled to a gas chromatograph and a mass spectrometer (evolved gas analysis) were performed on DyCl3·6H2O to understand the phase transformation to DyOCl (and Dy2O3) as a function of temperature and time at temperature. DyOCl compound with the tetragonal P4/nmm space group is composed of the alternating layers of (DyO)n and nCl− along the c-axis. [ABSTRACT FROM AUTHOR]

The reaction between rare earth oxychloride (REOCl) and water was investigated. X-ray diffractometer, volumetric titrations, FTIR spectrograph and scanning electron microscope were used to determine the reaction process and the reaction products. It was found that the reaction could be concluded as follows: 5REOCl(s) + 5H2O(l) = 2RE2(OH)5Cl(s) + RE3+(aq) + 3Cl−(aq). Based on this reaction, a new method for determining the purity of anhydrous rare earth chloride was proposed. Compared with the conventional method, the maximum absolute error decreased from 22 to < 1% and the maximum relative error decreased from 111 to < 4% under the experimental conditions. [ABSTRACT FROM AUTHOR]

The toxicity of the organic dyes presents in the environment due to polluted discharge from industries is a real dilemma in the world. Here, the problem was addressed with the synthesis of new quaternary mineral cupric antimony oxychloride (CAO) during the study of Cu–Sb–O–Cl system in absence of solvents. The morphological analysis showed that synthesized matrix is rough and uneven with round and cylindrical shapes. The composition of nanomaterial verified the elemental composition as Cu, Sb and Cl. The XRD analysis revealed that synthesized product CAO is crystalline in nature where crystallite size was estimated in the range of 2–8 nm. The bond vibrations were studied through Fourier transforms infrared spectroscopy to confirm the symmetric and asymmetric vibrations in the matrix. The material parameters (grain size, dislocation line density, stresses and miller indices) of the synthesized material CAO were calculated using powder X-ray diffraction analysis. Thermogravimetric analysis was performed to study the decomposition behaviour and stability of the CAO. The copper ternary compound was used to mitigate the effect of organic dyes like Sunset yellow (26%), Methylene blue (23%), Brilliant green (20%), Methyl orange (14%) in the dyes polluted wastewater. [ABSTRACT FROM AUTHOR]

The reaction between GdO(s) and Cl(g) was studied in a high-resolution thermogravimetric system. The reaction product was GdOCl, which was the unique solid phase produced in all the temperature range studied. The GdOCl is subsequently chlorinated producing GdCl for temperatures above 1123 K. The system is under chemical control for temperatures below 723 K. It was found that the reaction order with respect to the chorine partial pressure is 0.77 and the activation energy is 132 kJ mol for the temperature range of 623-723 K. The global rate equation was developed. The GdOCl obtained was characterized by X-ray diffraction, scanning electron microscopy and magnetic measurements. The structure of GdOCl was refined with the Rietveld method, and it crystallized in a tetragonal form of REOX possessing the Matlockite-type (PbFCl) structure. The magnetic measurements indicated that the sample is paramagnetic at all the measurement ranges. The parameters of the Curie-Weiss law obtained were as follows: θ = −12.0 K, C = 7.9592 emu K mol and µ = 7.98 µ. [ABSTRACT FROM AUTHOR]

The concentration dependence of the quantum yield of luminescence of Tm3+ ions in an oxychloride matrix has been measured in individual bands of their luminescence excited at different wavelengths. The concentration dependences of the quantum yield of luminescence were calculated with allowance for the effect of the unintentional impurity of rare-earth ions. The cross-relaxation nature of the concentration dependence of the rare-earth ion luminescence is discussed. [ABSTRACT FROM AUTHOR]