Decomposition Ethanol

The ttihydtate is very soluble in water and ethanol. Decomposition begins around 80°C upon formation of the basic salt. At temperatures of 180°C the oxide is produced. 

Catalysts were prepared by impregnation using cobalt (ii) nitrate. Co/A1203 was the most the active and selective catalyst. Suppresses the ethanol decomposition and CO methanation reactions... 

SRE (Fig. 7) and POE (Fig. 10) reactions, a maximum yield of H2 could be attained in the OSRE reaction above 600 °C because CH4, if formed as an intermediate by ethanol decomposition could be completely converted into syngas above this temperature.7,8,10,109 The participation of reverse WGS reaction at high temperature leads to an increase in CO composition above 400 °C with a concomitant decrease in the composition of C02. Thus, at higher operating temperatures of above 600 °C, the system would produce mainly syngas rather than a mixture of H2 and C02. A comparison of equilibrium compositions of POE and OSRE reactions indicates that the presence of steam in this system increases the maximum yield of H2 from about 50% in the POE reaction (Fig. 10) to about 65% in the OSRE, and this is very close to that observed in the SRE reaction (around 70%) due to the participation of steam... 

H2 production technologies based on natural gas. Operating the reaction at relatively lower temperature, between 300 and 450 °C could minimize the CO formation because the equilibria for WGS and CO oxidation reactions are thermodynamically more favorable at lower temperatures. In order to achieve this goal, highly selective catalysts that are specific for reforming via acetaldehyde formation rather than ethanol decomposition to CH4 and/or ethylene are required. The success in the development of ethanol-based H2 production technology therefore relies on the development of a highly active, selective and stable catalyst. 

They reported that the catalyst exhibits very high selectivity to hydrogen and carbon dioxide. The CO methanation and ethanol decomposition are considerably reduced. In addition, coke formation is strongly depressed because of the benefits induced by the use of the basic support, which modify positively the electronic properties of Ni. 

The interaction of acetylene with Mg(001) was investigated by LEED (198-200). At 88 K, C2H2 molecules lie almost parallel to the surface, and neither molecule nor substrate distortions have been observed, indicating that only a weak physisorption occurs. Calculations with semiempirical potentials confirm the structure determined by LEED (199). The isomerization of d.v-2-butene on MgO has been reported (201). The dissociation of cyclopen-tadiene on a few active acid-base pair sites of totally dehydrated MgO was followed by IR spectroscopy, and the formation of surface hydroxyl groups and C5H5 species was proposed (202). Methanol decomposition (203) and ethanol decomposition (204, 205) have been reported. 

Barj et al." and Pommier et al. examined thermal decomposition of Mg[Al(0-iec-Bu)4]2 in ethanol decomposition starts at 283°C, yielding an essentially amorphous product, while the reaction at 360°C yields partially crystallized MgAl204 spinel. The product consisted of secondary particles with a size of 3 pm, which is easily disaggregated by ultrasonic treatment into 0.02 pm primary particles. They also reported that thermal dehydration of ethanol becomes significant at temperatures higher than 360°C. Therefore crystallization of this product seems to occm with the aid of water formed by dehydration of the solvent. 

Cu was loaded on Raney Ni. The catalyst contained 68.9% Ni, 28.2% Cu, and 2.9% Al. Production of H2 + CH4 + C02 by coupling low-temperature ethanol decomposition and WGS reaction is more energy efficient and suitable for hybrid vehicles. 

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