Reaction Mechanism for the Thermal Decomposition of BCl3/CH4/H2Gas Mixtures

2011 ◽  
Vol 115 (42) ◽  
pp. 11579-11588 ◽  
Author(s):  
Guillaume Reinisch ◽  
Gérard L. Vignoles ◽  
Jean-Marc Leyssale
2015 ◽  
Vol 3 (22) ◽  
pp. 12044-12050 ◽  
Author(s):  
Cai-Chao Ye ◽  
Qi An ◽  
Tao Cheng ◽  
Sergey Zybin ◽  
Saber Naserifar ◽  
...  

A variety of initial reactions are favorable for MTO and MTO3N, two possible candidates for green energetic materials.


2002 ◽  
Vol 56 (6) ◽  
pp. 231-237 ◽  
Author(s):  
Mario Campari ◽  
Ana Tavares ◽  
Sergio Trasatti

Ti/RhOx electrodes were prepared at 400-600?C by thermal decomposition of Rh chloride. Oxide layers were studied by SEM, cyclic voltammetry and steady-state E-j curves In 0.5 mol dm-3 H2SO4 solution. Voltammetric charge exhibits a maximum at 430?C with fresh electrodes which shifts to 470?C after use for H2 evolution. H2 discharge first produces a decrease in voltammetric charge, then an activation with final settlement to a constant behaviour for "aged" electrodes. H2 evolution on stable RhOx surfaces takes place with 40 mV Tafel slope and a reaction order of 2.5. The fractional reaction order indicates that the surface response to pH is that typical of oxides even for "aged" electrodes. A reaction mechanism is proposed.


2019 ◽  
Vol 10 (05) ◽  
pp. 153-170 ◽  
Author(s):  
Itab Youssef ◽  
Sécou Sall ◽  
Thierry Dintzer ◽  
Sana Labidi ◽  
Corinne Petit

2019 ◽  
Vol 9 (1) ◽  
pp. 22-35
Author(s):  
Bratati Das ◽  
Ashis Bhattacharjee

Background: Thermal decomposition of iron-bearing organometallic complex acetyl ferrocene, (C5H4COCH3)Fe(C5H5), leads to hematite (α-Fe2O3) nanoparticles. Presence of maliec anhydride, C4H2O3 as co-precursor during thermal decomposition modifies the size of the particles as well as the quantity of the reaction product significantly. Objective: Kinetic analysis of the solid-state thermal reaction of acetyl ferrocene in the presence of varying amount of co-precursor maliec anhydride under inert reaction atmosphere has been studied in order to understand the reaction mechanism involved behind the formation of hematite and the role of co-precursor in the reaction process. For this purpose, reaction kinetic analysis of three mixtures of acetyl ferrocene and maliec anhydride has been carried out. Methods: Thermogravimetry under non-isothermal protocol with multiple heating rates has been employed. The data are analyzed using model-free iso-conversional kinetic techniques to estimate the activation energy of reaction and reaction rate. The most-probable reaction mechanism has been identified by master plot method. The kinetic triplets (activation energy, reaction rate, most probable reaction mechanism function) have been employed to estimate the thermodynamic triplets (ΔS, ΔH and ΔG). Observations: Acetyl Ferrocene (AFc) undergoes thermal decomposition in a four-step process leaving certain residual mass whereas maliec anhydride (MA) undergoes complete mass loss owing to melting followed by evaporation. In contrast, the (AFc1-x-MAx) mixtures undergo thermal decomposition through a two-step process, and the decompositions are completed at much lower temperatures than that in AFc. The estimated activation energy and reaction rate values are found strongly dependent on the extent of conversion as well as on the extent of mixing. Introduction of MA in the solid reaction atmosphere of AFc in one hand reduces the activation energy required by AFc to undergo thermal decomposition and the reaction rate, while on the other hand varies the nature of reaction mechanism involved. Results: The range of reaction rate values estimated for the mixtures indicate that the activated complexes during Step-I of thermal decomposition may be treated as ‘loose’ complex whereas ‘tight’ complex for the Step-II. From the estimated entropy values, thermal process of (AFc1-x-MAx) mixture for Steps I and II may be interpreted as ‘‘slow’’ stage. Conclusion: Variation of Gibb’s free energy with the fraction of maliec anhydride in the mixtures for Step-I and II indicate that the thermal processes of changing the corresponding activated complexes are non-spontaneous at room temperature.


1992 ◽  
Vol 296 ◽  
Author(s):  
Tod R. Botcher ◽  
Charles A. Wight

AbstractThin films of RDX (1,3,5-trinitro-1,3,5-triazine) have been prepared by vapor deposition onto a 77 K substrate window and pyrolyzed with a pulsed CO2 laser. Each sample is rapidly quenched after the laser pulse by heat conduction into the cold substrate, and the initial reaction products are trapped on the window for examination by transmission FTIR spectroscopy. We have detected N2O4, the dimer of nitrogen dioxide, as an initial condensed phase pyrolysis product, confirming that scission of one of the N-N bonds is the first step in the reaction mechanism. No evidence was found for formation of methylene nitramine via a proposed concerted depolymerization pathway.


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