Ethane decomposition temperature

Ethane, C2H , dissociates into methyl radicals by a first-order reaction at elevated temperatures. If 250. mg of ethane is confined to a 500.-mL reaction vessel and heated to 700°C, what is the initial rate of ethane decomposition if k = 5.5 X 10 4 s-1 in the rate law (for the rate of dissociation of C2H6) ... 

The inhibition of the ethane decomposition by NO has been studied by a number of workers.There seems to be a maximum inhibition of the reaction somewhere in the range 2 to 10 per cent (NO). The effect is least at higher temperatures and also at higher total pressures. In addition the effect seems to be greatest on the initial rate, the inhibited reaction appearing to follow the normal reaction after several per cent decomposition. 

Phosphorus ylides react with organogold halides to give a variety of interesting structures whose thermal decomposition has been studied. The compound 52 is stable at its melting point of 205 °C but decomposes at higher temperatures with clean elimination of ethane to afford 5370. Bulky groups also lead to considerable stabilization and compounds such as 54 and 55 have decomposition temperatures above 150°C71. Finally, the cyclic compound 56 cleanly eliminates ethane at 153-155 °C to give 5772. 

Plasma Catalysis of Hydrogen Production by Direct Decomposition (Pyrolysis) of Ethane. Interpreting the plasma-catalytic effect of ethane decomposition and hydrogen production illustrated in Fig. 10-10, explain why the application of thermal plasma results in an increase of gas temperature, while application of non-equilibrium plasma results in gas cooling and additional hydrogen production. Compare the thermodynamics of these systems with that of refrigerators and heat pumps. 

Most highly polar and ionic species are not amenable to processing with desirable solvents such as carbon dioxide or any other solvent such as water that has a higher critical temperature well above the decomposition temperature of many solutes. In such instances, the combination of the unique properties of supercritical fluids with those of micro-emulsions can be used to increase the range of applications of supercritical fluids. The resulting thermodynamically stable systems generally contain water, a surfactant and a supercritical fluid (as opposed to a non-polar liquid in liquid micro-emulsions). The possible supercritical fluids that could be used in these systems include carbon dioxide, ethylene, ethane, propane, propylene, n-butane, and n-pentane while many ionic and non-ionic surfactants can be used. The major difference between the liquid based emulsions and the supercritical ones is the effect of pressure. The pressure affects the miscibility gaps as well as the microstracture of the micro-emulsion phase. 

Constancy of Initiation Reaction, Despite the variation in the over-all rate constant at a particular temperature of nearly an order of magnitude, depending on the pressure and dilution, the rate constant for the initiation reaction is remarkably constant. This is illustrated by Table III, which gives rate constants ki for 675°C. Relatively minor corrections for secondary methane were necessary at this low temperature—the ethane decomposition never... 

The decomposition of sodium methoxide commences at temperatures above 623 K (Figure 15.14). The gaseous products formed on decomposition were mainly methane (mass 16) with minor quantities of ethane (mass 30) and propylene (mass 42). However, Pfeifer et al. [36] have reported the decomposition temperatures of sodium... 

Burcat A, Skinner G B, Crossley R W and Scheller K 1973 High temperature decomposition of ethane Int. J. Chem. Kinetics 5 345-52... 

When acetylene is recovered, absorption—desorption towers are used. In the first tower, acetylene is absorbed in acetone, dimethylformarnide, or methylpyroUidinone (66,67). In the second tower, absorbed ethylene and ethane are rejected. In the third tower, acetylene is desorbed. Since acetylene decomposition can result at certain conditions of temperature, pressure, and composition, for safety reasons, the design of this unit is critical. The handling of pure acetylene streams requires specific design considerations such as the use of flame arrestors. 

Cracking temperatures are somewhat less than those observed with thermal pyrolysis. Most of these catalysts affect the initiation of pyrolysis reactions and increase the overall reaction rate of feed decomposition (85). AppHcabiUty of this process to ethane cracking is questionable since equiUbrium of ethane to ethylene and hydrogen is not altered by a catalyst, and hence selectivity to olefins at lower catalyst temperatures may be inferior to that of conventional thermal cracking. SuitabiUty of this process for heavy feeds like condensates and gas oils has yet to be demonstrated. 

Polyethylene displays good heat resistance in the absence of oxygen in vacuum or in an inert gas atmosphere, up to the temperature of 290°C. Higher temperature brings about the molecular-chain scission followed by a drop in the molecular-weight average. At temperatures in excess of 360°C the formation of volatile decomposition products can be observed. The main components are as follows ethane, propane, -butane, n-pentane, propylene, butenes and pentenes [7]. 

It has been generally accepted that the thermal decomposition of paraffinic hydrocarbons proceeds via a free radical chain mechanism [2], In order to explain the different product distributions obtained in terms of experimental conditions (temperature, pressure), two mechanisms were proposed. The first one was by Kossiakoff and Rice [3], This R-K model comes from the studies of low molecular weight alkanes at high temperature (> 600 °C) and atmospheric pressure. In these conditions, the unimolecular reactions are favoured. The alkyl radicals undergo successive decomposition by [3-scission, the main primary products are methane, ethane and 1-alkenes [4], The second one was proposed by Fabuss, Smith and Satterfield [5]. It is adapted to low temperature (< 450 °C) but high pressure (> 100 bar). In this case, the bimolecular reactions are favoured (radical addition, hydrogen abstraction). Thus, an equimolar distribution ofn-alkanes and 1-alkenes is obtained. 

The pyrolysis of diethyl mercury has been studied using a nitrogen carrier flow system87 both in the presence and absence of toluene. The experimental conditions used were total pressure = 10+1 torr with 0.4 torr partial pressure of toluene, alkyl pressure 1-10 x 10 2 torr, decomposition 10-75 % and contact time 0.1-0.3 sec. The presence of toluene had no effect on the rate coefficient, the observed ethane/ethylene ratio ( 1) or the C4/C2 ratio ( 4). These ratios were essentially independent of temperature. 

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