Thermal Decomposition of Tetraethylammonium Perchlorate

Abstract: The thermolysis of various substituted ammonium salts of nitric and perchloric acids has been reviewed in the present communication The mechanistic aspects of thermal decomposition of these salts have been discussed critically It has been observed that the proton transfer process do play a major role during thermolysis of these salts The plausible decomposition pathways have also been described

Abstract: Thermal decomposition of tetraethyl ammonium tetrafluoroborate has been studied employing simultaneous techniques of TG–DTG–DSC—quadrupole mass spectrometric techniques in an inert atmosphere of pure Helium gas at a sample heating rate of 5 K min−1 employing a platinum crucible. The observed decomposition paths are the most commonly expected Hofmann elimination and substitution reactions paths.

Abstract: Composite materials based on [PVxW12-xO40](3+x)− with x = 1 or 2 (PVW and PV2W respectively), included in poly(acrylic acid-co-acrylamide) gel (PAACA), were synthesized. The samples were characterized by different techniques such as FT-IR, 31P MAS-NMR, 51V-NMR, XRD, DTA-TGA, UV–vis DRS, and the acidic properties were estimated by means of potentiometric titration with n-butylamine. Samples containing 10, 20 and 30% (w/w) of polyoxotungstovanadate (POTV) were prepared by inclusion of the POTV in the polymer during its synthesis. According to Fourier transform infra-red and magic angle spinning-nuclear magnetic resonance studies, the predominat anion present in the samples is [PVxW12-xO40](3+x)−, and there is no evidence of its decomposition during the synthesis of hybrid materials and the drying step. According to XRD results, these anions are greatly dispersed in the PAACA or present as amorphous phases. UV–vis DRS data reveal that the samples synthesized using POTV with two vanadium atoms (PAACA-PV2W) exhibit lower values of absorption edge energy than those prepared using PVW (PAACA-PVW), which correlates with a higher oxidizing capacity. The potentiometric titration shows strong acid sites of the hybrid materials, and their number increases with the number of vanadium atoms and with the amount of POTV incorporated in the PAACA grid. The hybrid materials prepared by inclusion of POTV during the polymer synthesis exhibit appropriate physicochemical features to catalyze the oxidation of diphenyl sulfide (DPS) to its sulfone employing acetonitrile as solvent H2O2 as a green oxidant. The samples with 30% w/w of POVT, which show higher catalytic performance, are suitable for the DPS oxidation and can be reused without remarkable drop of their catalytic activity. Furthermore, they show high activity as a catalyst in the oxidation reaction of 4,4´-diamino diphenyl sulfide to the corresponding sulfone (dapsone) used for malaria treatment.

Abstract: Mechanistic aspects of the thermal decomposition of benzyl-triethyl-ammonium tetrafluoroborate (BTEATFB) employing simultaneous TG-DSC coupled with a quadrupole mass spectrometer are considered in this work The experiments were conducted in an inert atmosphere of helium The decomposition of BTEATFB proceeds through several competing mechanisms While nucleophilic substitution reaction occurs through the formation of a tertiary amine and plays an important role in the initial stages of the decomposition, and the probability of Hoffman elimination also exists

Abstract: Thermal decomposition of guanidinium perchlorate has been studied by thermogravimetry, differential thermal analysis, mass spectrometry and X-ray diffractometry. The title compound undergoes crystallographic phase transformation at 180°C before melting at 255°C. It decomposes exothermally into gaseous products in the temperature range 275°C–325°C. The mass spectral results suggest that the compound undergoes thermal decomposition into neutral particles which are then vapourized, ionized and oxidized. The fragment cyanamide is found to undergo trimerization to give melamine.

Abstract: Inorganic molecules (ions) and ligands are classified into diatomic, triatomic, four-atomic, five-atomic, six-atomic, and seven-atomic types, and their normal modes of vibration are illustrated and the corresponding vibrational frequencies are listed for each type. Molecules of other types are grouped into compounds of boron, carbon, silicon, nitrogen, phosphorus, and sulfur, and the structures and infrared (IR)/Raman spectra of select examples are shown for each group. Group frequency charts including band assignments are shown for phosphorus and sulfur compounds. Other group frequency charts include hydrogen stretching frequencies, halogen stretching frequencies, oxygen stretching and bending frequencies, inorganic ions, and metal complexes containing simple coordinating ligands. Keywords: inorganic compounds; coordination compounds; diatomic molecules (ligands); triatomic molecules (ligands); four-atomic molecules (ligands); five-atomic molecules (ligands); six-atomic molecules (ligands); seven-atomic molecules (ligands); boron compounds; carbon compounds; silicon compounds; nitrogen compounds; phosphorus compounds; sulfur compounds; group frequency charts