Differential Thermal Analysis of Decomposition Reactions of Potassium Chlorate in the Presence of the Mixture of Positive Catalysts and Sodium Chloride

This study examined the thermal behavior of cast gypsum specimens, with and without additives, by means of simultaneous differential thermal analysis-thermogravimetry (DTA-TG) and dilatometry. Specimens were prepared from wet-calcined hemihydrates (Hydrocal and Den-site). The additives studied were boric acid (H3BO 3) and sodium chloride (NaCl), and these were added to the hemihydrate powders in concentrations of 2 wt% (in the case of H3BO3) and 0.5 wt% (in the case of NaCl). A large shrinkage was observed in the range of 300 to 500°C, and this was greatly reduced when either H3BO3 or NaCl was present. The dehydration of gypsum (calcium sulfate dihydrate) was not completed until the initial stage of this large shrinkage was reached, but the phase transition of calcium sulfate anhydrite (III-CaSO4 to II-CaSO4) was the major cause for the large shrinkage. This phase transition occurred over a much wider temperature range than that suggested by the DTA-TG results. Dehydration conditions similar to those employed in wet calcination of gypsum appeared to be produced under atmospheric pressure when NaCl was present.

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The use of dynamic thermogravimetry and gas chromatography to the study of the chemical kinetics of solid-state decomposition reactions of some selected crystalline amino acids (and comparison of the method of differential thermal analysis)

Thermochimica Acta ◽

10.1016/0040-6031(78)85065-5 ◽

1978 ◽

Vol 23 (2) ◽

pp. 233-248 ◽

Cited By ~ 11

Author(s):

G.W.C. Hung

Keyword(s):

Thermal Analysis ◽

Amino Acids ◽

Gas Chromatography ◽

Differential Thermal Analysis ◽

Solid State ◽

Chemical Kinetics ◽

Decomposition Reactions ◽

Solid State Decomposition ◽

Crystalline Amino Acids ◽

Kinetics Of

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A Study of the Decomposition of Sodium Azide using Differential Thermal Analysis

Canadian Journal of Chemistry ◽

10.1139/v73-028 ◽

1973 ◽

Vol 51 (2) ◽

pp. 183-186 ◽

Cited By ~ 8

Author(s):

H. Potvin ◽

M. H. Back

Keyword(s):

Activation Energy ◽

Thermal Analysis ◽

Differential Thermal Analysis ◽

Sodium Chloride ◽

Thermogravimetric Analysis ◽

Sodium Azide ◽

Major Peak ◽

Inhibiting Effect ◽

Decomposition Processes ◽

Major Process

Differential thermal analysis and thermogravimetric analysis of sodium azide diluted with sodium chloride both show one major peak followed by a second minor one. This is interpreted as indicating the occurrence of two distinct decomposition processes. The activation energy of the first, major process was 36 kcal/mol, which agrees with values reported previously from measurements of the rate of nitrogen evolution. Differential thermal analysis of sodium azide mixed with alumina was complicated by the presence of variable amounts of water adsorbed on the alumina. The presence of water was shown to have an inhibiting effect on the decomposition.

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Catalytic effect of metal oxides on thermal decomposition reactions. II. Catalytic effect of metal oxides on the thermal decomposition of potassium chlorate and potassium perchlorate as detected by thermal analysis methods

The Journal of Physical Chemistry ◽

10.1021/j100712a002 ◽

1970 ◽

Vol 74 (18) ◽

pp. 3317-3324 ◽

Cited By ~ 76

Author(s):

Winfried K. Rudloff ◽

Eli S. Freeman

Keyword(s):

Thermal Analysis ◽

Thermal Decomposition ◽

Metal Oxides ◽

Catalytic Effect ◽

Potassium Chlorate ◽

Potassium Perchlorate ◽

Decomposition Reactions ◽

Analysis Methods

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NEW MIXED TETRADENTATE CHELATES OF Co(III) WITH ETHYLENDIIMINO-BIS-DIBENZOYLMETHANE

Southern Brazilian Journal of Chemistry - Southern Brazilian Journal of Chemistry, Volume 28, No. 28, 2020 ◽

10.48141/sbjchem.v10.n11.2002.40_2002.pdf ◽

2002 ◽

Vol 10 (11) ◽

pp. 39-48

Author(s):

Ion Ganescu ◽

George Bratulescu ◽

Ion Papa ◽

Anca Ganescu ◽

Daniela Cartana ◽

...

Keyword(s):

Thermal Stability ◽

Thermal Analysis ◽

Differential Thermal Analysis ◽

Structural Properties ◽

Uv Spectra ◽

Decomposition Reactions ◽

Complex Salts ◽

Double Decomposition ◽

Thermal Stability Of ◽

Ir And Uv Spectra

Five new chelates of Co(III) of the [Co(dibenzec)(amine)2]+ type (dibenzec.H2-ethylenediimino-bis-dibenzoylmethane: C32H28N202, amine=aniline, o-anisidine, p-toluidine, m-xilidine, a-naphtilamine) were synthetized and characterized by isolation of thirty-four new complex salts by means of the double decomposition reactions. The thermal stability of the complexes was studied by means of differential thermal analysis. The structural properties were discussed on the basis of IR and UV spectra

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Zeolites Fit For A Crown: Probing Host-Guest Interactions with Thermogravimetric Methods

10.26434/chemrxiv.7429961 ◽

2018 ◽

Author(s):

Asel Sartbaeva ◽

Paul R. Raithby ◽

Remi Castaing ◽

Antony Nearchou

Keyword(s):

Mass Spectrometry ◽

Thermal Analysis ◽

Differential Thermal Analysis ◽

Petrochemical Industry ◽

Rational Use ◽

New Methodologies ◽

First Time ◽

Kinetics Of

Through a combination of thermogravimetry, mass spectrometry and differential thermal analysis, we demonstrate for the first time that all four zeolites show experimental differences in their host-guest interactions with 18C6. In addition, we have estimated the kinetics of 18C6 decomposition, which is a technique that has not been applied to zeolites previously. Using these findings as a toolkit, a more rational use of OSDAs can be utilised to prepare designer zeolites. Furthermore, the new methodologies presented herein can be applied to current zeolites, such as MFI-type zeolites used in the petrochemical industry.

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PHASE EQUILIBRIUM IN THE AS2TE3-TM2TE3 SYSTEM.

EurasianUnionScientists ◽

10.31618/esu.2413-9335.2020.5.77.985 ◽

2020 ◽

Vol 5 (8(77)) ◽

pp. 65-68

Author(s):

Teymur Mammad Ilyasly ◽

Rahman Hasanaga Fatullazade ◽

Zakir Islam Ismailov ◽

Nigar Nadir Jafarova

Keyword(s):

Thermal Analysis ◽

Solid Solution ◽

Differential Thermal Analysis ◽

Phase Equilibrium ◽

Physicochemical Properties ◽

Thermal Effects ◽

Isothermal Annealing ◽

Intermediate Phase ◽

Physicochemical Analysis ◽

Two Phases

The synthesis of alloys of the system was carried out stepwise in rotary furnaces. The synthesis mode was selected based on the physicochemical properties of the elementary components. For homogenization, the alloys were subjected to isothermal annealing at 750 and 1275 K, depending on the Tm2Te3 concentration, for 250 h after homogenization of the alloys, they were subjected to physicochemical analysis. The results of differential thermal analysis showed that reversible thermal effects are observed in the alloys of the system. In alloys in a 1: 1 ratio, a new intermediate phase is formed with a composition corresponding to the TmAsTe3 compound. The homogeneity area is observed in the concentration range 52.5-47.5. It was found that in the concentration range 98.5-52.5 Tm2Te3 there are two phases - a mixture of β and of the solid solution, and in the concentration range of 47.51 mol% Tm2Te3 phases and α are in equilibrium. ) 66 The eutectic has coordinates of 11.5 mol Tm2Te3 at a temperature of 575 K.

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PENINGKATAN LAJU DISOLUSI ACYCLOVIR DENGAN METODE SISTEM DISPERSI PADAT MENGGUNAKAN POLOXAMER 188

SCIENTIA : Jurnal Farmasi dan Kesehatan ◽

10.36434/scientia.v5i1.61 ◽

2016 ◽

Vol 5 (1) ◽

pp. 6

Author(s):

Budi Setiawan ◽

Erizal Zaini ◽

Salman Umar

Keyword(s):

Electron Microscopy ◽

Thermal Analysis ◽

Scanning Electron Microscopy ◽

Fourier Transform ◽

Differential Thermal Analysis ◽

Fourier Transform Infrared ◽

X Ray Diffraction ◽

Poloxamer 188 ◽

X Ray ◽

Scanning Electron

Sebuah penelitian tentang sistem dispersi padat dari asiklovir dengan poloxamer 188 telah dilakukan formulasi dengan pencampuran secara fisika dengan rasio 1 : 1, 1 : 3, 1 : 5 dan dispersi padat 1 : 1, 1 : 3, 1 : 5 dan penggilingan 1:1 sebagai pembanding. Dispersi padat dibuat menggunakan metode pencairan (fusi), yang digabung dengan poloxamer 188 pada hotplate kemudian asiklovir dimasukkan ke dalam hasil poloxamer 188 lalu di kocok hingga membentuk masa homogen. Semua formula yang terbentuk termasuk asiklovir poloxamer 188 murni dianalisis karakterisasinya dengan Differential Thermal Analysis (DTA), X-ray Diffraction, Scanning Electron Microscopy (SEM), dan Fourier Transform Infrared (FTIR), kemudian pengambilan dilakukan (penentuan kadar) mengunakan spektrofotometer UV pada panjang gelombang 257,08 nm dan uji laju disolusi dengan aquadest bebas CO2 menggunakan metode dayung. Hasil pengambilan (penentuan kadar) menunjukkan bahwa semua formula memenuhi persyaratan farmakope Amerika edisi 30 dan farmakope Indonesia edisi 4 yaitu 95-110%. Sedangkan hasil uji laju disolusi untuk campuran fisik 1: 1, dan dispersi padat 1: 1, dan penggilingan 1: 1 menunjukkan peningkatan yang nyata dibandingkan asiklovir murni. Hal ini juga dapat dilihat dari hasil perhitungan statistik menggunakan analisis varian satu arah SPSS 17.

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Kinetics of temperature-programmed reactivation of a hydrodesulphurization catalyst

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19833340 ◽

1983 ◽

Vol 48 (12) ◽

pp. 3340-3355 ◽

Cited By ~ 2

Author(s):

Pavel Fott ◽

Pavel Šebesta

Keyword(s):

Carbon Dioxide ◽

Thermal Analysis ◽

Differential Thermal Analysis ◽

Thin Layer ◽

Kinetic Parameters ◽

Diffusion Region ◽

Reaction Heat ◽

Gaseous Products ◽

Temperature Programmed ◽

Kinetics Of

The kinetic parameters of reactivation of a carbonized hydrodesulphurization (HDS) catalyst by air were evaluated from combined thermogravimetric (TG) and differential thermal analysis (DTA) data. In addition, the gaseous products leaving a temperature-programmed reactor with a thin layer of catalyst were analyzed chromatographically. Two exothermic processes were found to take part in the reactivation, and their kinetics were described by 1st order equations. In the first process (180-400 °C), sulphur in Co and Mo sulphides is oxidized to sulphur dioxide; in the second process (300-540 °C), in which the essential portion of heat is produced, the deposited carbon is oxidized to give predominantly carbon dioxide. If the reaction heat is not removed efficiently enough, ignition of the catalyst takes place, which is associated with a transition to the diffusion region. The application of the obtained kinetic parameters to modelling a temperature-programmed reactivation is illustrated on the case of a single particle.

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