Sulfur exchange and decomposition kinetics in solid Na2S2O3

McAmish, L.H.; Johnston, F. J.

doi:10.1016/0022-1902(76)80299-0

Cited by 12 publications

(12 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…2 ) models, the integral forms of which are g(α [23] were fitted to the Coats-Redfern (7) to obtain the activation energy (E) International Journal of Chemical Engineering and the preexponential factor for degradation of these polyesters. The E and A for the two different g(α) functions were calculated at constant heating rates by fitting ln g(α)/T 2 versus 1/T plots.…”

Section: Resultsmentioning

confidence: 99%

“…where k is the degradation rate constant, x is a transmission coefficient (unity for monomolecular reactions), k B is the Boltzmann constant, h is the corresponding Planck's constant, e = 2.7183 is the Neper number, and ΔS is the change of entropy for the active complex formation [23]. Equation (1) is based on the basic Arrhenius equation:…”

Section: Theoretical Backgroundmentioning

confidence: 99%

See 1 more Smart Citation

Enthalpy-Entropy Compensation in Polyester Degradation Reactions

Al‐Mulla

2012

International Journal of Chemical Engineering

View full text Add to dashboard Cite

In an earlier work the author had studied the degradation kinetics of polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), and polybutylene terephthalate (PBT) under nonisothermal conditions in air and N 2 at heating rates of 5, 10, 15, and 20• C/min. In this paper the kinetic degradation parameters of PET, PTT, and PBT were estimated using the CoatsRedfern method for two different weight loss regions ranging from 2-8% (Zone I) and 8-40% (Zone II). A comparative analysis of the enthalpy-entropy compensation effect for these polyesters in air and N 2 is presented. A linear relationship was found to exist between entropy and enthalpy values. The following criteria were applied to establish an enthalpy-entropy compensation effect and to check the presence of an isokinetic temperature: (a) Exner's plot of log k 3T1 versus log k 3T2 , and (b) Krug et al. linear regression of ΔH versus ΔG. By the use of the latter two methods, varying isokinetic temperatures were obtained. These temperatures were not in the range of the experimental work conducted, indicating that these systems do not display compensation phenomena.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Theoretical Backgroundmentioning

confidence: 99%

Enthalpy-Entropy Compensation in Polyester Degradation Reactions

Al‐Mulla

2012

International Journal of Chemical Engineering

View full text Add to dashboard Cite

show abstract

“…8) and the thermodynamic equation relating the change of the Gibbs free energy with the changes of enthalpy and entropy. [21][22][23][24]…”

Section: Theoretical Approach and Calculation Proceduresmentioning

confidence: 99%

Study on the Thermochemical and Kinetic Characteristics of Alkali Treated Rice Husk

Markovska

Bogdanov

Nedelchev

et al. 2010

J Chinese Chemical Soc

View full text Add to dashboard Cite

The effective utilization of waste rice husk requires detailed studies on the kinetics and mechanism of their thermal and chemical treatment. The present work is a comparative study on the thermo-chemical and kinetic characteristics of thermal degradation of raw and treated with NaOH rice husk. The optimal conditions for extraction of SiO 2 from rice husk in the form of Na 2 SiO 3 were determined using thermal analysis (TA), scanning electron microscope (SEM) and elemental analysis. The experiments were carried out under conditions of non-isothermal heating in air and nitrogen atmosphere. Using different kinetic models, the values of the effective kinetic parameters, characterizing the destruction process were determined.

show abstract

“…Über den intraionischen S-Austausch liegt eine Reihe kinetischer Untersuchungen vor [1][2][3]; der vorgeschlagene Mechanismus der Trennung der S-S-Bindung mit sukzessiver Übertragung der Sauerstoffteilchen [3] Dichten und Dielektrizitätskonstanten der Abschreckprodukte werden angegeben [2].…”

Section: Introductionunclassified

Ein Besuch in Wadi Madhah/Sultanat Oman

1982

Zeitschrift Für Wirtschaftsgeographie

View full text Add to dashboard Cite

Sodium Thiosulphate, Polymorphism, Solid ElectrolyteNa2S2C>3 crystallizes in 4 modifications. The familiar monoclinic a-form stable at ambient temperature transforms into the trigonal /3-form at 330 °C which at 388 °C converts to bcc y-Na2S203. These transformations are reversible. Unstable orthorhombic a'-Na2S2C>3(Pna 2i) is obtained by dehydration of the pentahydrate or by cooling the ß-phase.The y-phase decomposes in sealed ampoule to Na2SC>4 and NaSs; decomposition is slow below and rapid above 440 °C. Equilibrium displacement by distillation of sulphur accelerates decomposition even for /?-Na2S203, and maintaining low sulphur pressure by pumping gives Na2S03. ß-and y-Na2S2C>3 are superionic conductors; a dynamic model is presented for the /3-structure with Na+ conduction pathways originating from oscillation of the S0O3 2-tetrahedra. Structural relationships can be derived with respect to the arrangement of the thiosulphate groups.

show abstract

Sulfur exchange and decomposition kinetics in solid Na2S2O3

Cited by 12 publications

References 13 publications

Enthalpy-Entropy Compensation in Polyester Degradation Reactions

Enthalpy-Entropy Compensation in Polyester Degradation Reactions

Study on the Thermochemical and Kinetic Characteristics of Alkali Treated Rice Husk

Ein Besuch in Wadi Madhah/Sultanat Oman

Contact Info

Product

Resources

About