Potentialities of mass spectrometry on activation energy and secondary reactions determination of calcium oxalate thermal decomposition

The thermal decomposition of biallyl has been investigated from 977 – 1 070 °K at helium carrier gas pressures of 10–50 Torr. Under these conditions the rate of central C—C bond fission to give two allyl radicals can be measured without interference from secondary reactions. The reaction at the pressures employed is first order with respect to biallyl, but between first and second order in the total pressure. The temperature dependence of the rate constants, extrapolated to infinite pressure, and corrected to 298 °K, gives an activation energy of 45.7 kcal/mole for the reaction, corresponding to ΔHf(allyl) = 33.0 kcal/mole.

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Synthesis and Determination of the Kinetic Parameters for Non-Isothermal Decomposition of Complexes Ln(thd)3phen

Materials Science Forum ◽

10.4028/www.scientific.net/msf.530-531.506 ◽

2006 ◽

Vol 530-531 ◽

pp. 506-512 ◽

Cited By ~ 1

Author(s):

Wilton Silva Lopes ◽

Crislene Rodrigues da Silva Morais ◽

A.G. de Souza

Keyword(s):

Activation Energy ◽

Thermal Decomposition ◽

Lanthanide Complexes ◽

Reaction Order ◽

Decomposition Reaction ◽

Cylindrical Symmetry ◽

Boundary Reaction ◽

Phase Boundary Reaction ◽

Kinetics Of

In this work the kinetics of the thermal decomposition of two ß-diketone lanthanide complexes of the general formula Ln(thd)3phen (where Ln = Nd+3 or Tm+3, thd = 2,2,6,6- tetramethyl-3,5-heptanodione and phen = 1,10-phenantroline) has been studied. The powders were characterized by several techniques. Thermal decomposition of the complexes was studied by non-isothermal thermogravimetry techniques. The kinetic model that best describes the process of the thermal decomposition of the complexes it was determined through the method proposed by Coats-Redfern. The average values the activation energy obtained were 136 and 114 kJ.mol-1 for the complexes Nd(thd)3phen and Tm(thd)3phen, respectively. The kinetic models that best described the thermal decomposition reaction the both complexes were R2. The model R2 indicating that the mechanism is controlled by phase-boundary reaction (cylindrical symmetry) and is defined by the function g(α) = 2[1-(1-a)1/2], indicating a mean reaction order. The values of activation energy suggests the following decreasing order of stability: Nd(thd)3phen > Tm(thd)3phen.

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Thermal Decomposition of Pyrite FeS2 under Reducing Conditions

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.2398 ◽

2010 ◽

Vol 654-656 ◽

pp. 2398-2401 ◽

Cited By ~ 4

Author(s):

Ludovic Charpentier ◽

Patrick J. Masset

Keyword(s):

Mass Spectrometry ◽

Activation Energy ◽

Differential Scanning Calorimetry ◽

Thermal Decomposition ◽

Scanning Calorimetry ◽

Reaction Progress ◽

Reducing Atmosphere ◽

Reducing Conditions

The thermal decomposition of pyrite was investigated under reducing atmosphere, e.g. p(O2)~10-6 bar. Thermogravimetric measurements were coupled with differential scanning calorimetry and mass spectrometry. Multi-scan method was used to calculate the values of the activation energy of the reaction of thermal decomposition of the pyrite. It was shown that the value of the activation energy of the decomposition of pyrite into pyrrhotite varies with the reaction progress. The values of activation energy vary from 250 to 350 kJ.mol-1.

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Determination of sulfur by thermal decomposition of 2-perimidinylammonium sulfate/isotope dilution mass spectrometry.

BUNSEKI KAGAKU ◽

10.2116/bunsekikagaku.36.7_t77 ◽

1987 ◽

Vol 36 (7) ◽

pp. T77-T80 ◽

Cited By ~ 2

Author(s):

Kazuo WATANABE ◽

Misao OUCHI

Keyword(s):

Mass Spectrometry ◽

Thermal Decomposition ◽

Isotope Dilution ◽

Isotope Dilution Mass Spectrometry

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DETERMINATION OF THERMAL DECOMPOSITION REACTION CHARACTERISTICS (A, E) OF WOOD SAMPLES FOR FIRE DYNAMICS SIMULATION

YBL Journal of Built Environment ◽

10.2478/jbe-2013-0008 ◽

2013 ◽

Vol 1 (2) ◽

pp. 13-24 ◽

Cited By ~ 1

Author(s):

László Beda ◽

Attila Szabó

Keyword(s):

Activation Energy ◽

Thermal Decomposition ◽

Decomposition Reaction ◽

Dynamics Simulation ◽

Fire Dynamics ◽

Exponential Factor ◽

Decomposition Reactions ◽

Reaction Characteristics ◽

Reaction Activation Energy

Abstract The purpose of this work is to determine the pre-exponential factor (A) and the reaction activation energy (E) of decomposition reactions that are needed for Fire Dynamics Simulation (FDS) using Derivatograph Q 1500D. The materials we investigated: Pine Wood Board (PWB), Multilayered Parquet Board (MPB), Particleboard Core (PBC) and Oriented Standard Board (OSB).

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