Reaction re-forming

At present, most commercial hydrogen is obtained as a by-product of petroleum refining in a sequence of two catalyzed reactions. The first is a re-forming reaction, in which a hydrocarbon and steam are converted into carbon monoxide and hydrogen over a nickel catalyst ... 

The mixture of products, called synthesis gas, is the starting point for the manufacture of many other compounds, including methanol. The re-forming reaction is followed by the shift reaction, in which the carbon monoxide in the synthesis gas reacts with more water ... 

Carbon monoxide, CO, is produced when carbon or organic compounds burn in a limited supply of air, as happens in cigarettes and badly tuned automobile engines. It is produced commercially as synthesis gas by the re-forming reaction (Section 14.3). Carbon monoxide is the formal anhydride of formic acid, HCOOH, and the gas can be produced in the laboratory by the dehydration of formic acid with hot, concentrated sulfuric acid ... 

Use Appendix 2A to determine (a) the standard reaction enthalpy (b) the standard entropy (c) the standard Gibbs energy at 25°C for the re-forming reaction of methane. 

However, unless the other reactant is a strong reducing agent, water acts as an oxidizing agent only at high temperatures, as in the re-forming reaction (Section 14.3). 

However, if one writes the reaction in this way, a point is missed—the presence in the incompletely re-formed gas of the powerful electrode poison, CO. Thus, the re-forming reaction proceeds via the mechanism ... 

In the refining process, a Ni-catalyzed re-forming reaction, produces products called synthesis gas. 

Theories of catalysis (2-5) would associate the activity with certain electronic and geometric attributes of the catalyst which are fundamental to our understanding of reaction mechanisms. The electronic mechanism for the heterogeneous dehydrogenation of hydrocarbons has been postulated by Weyl (6) to be similar to that of nitrous oxide decomposition. To clarify the electronic mechanism of re-forming reactions, the decomposition of nitrous oxide was studied. 

Czerwosz et al. s findings might be of particular interest to readers familiar with carbon formation on nickel and nickel-coated catalysts that had been exposed to hydrocarbons or carbon monoxide in hydrocarbon synthesis or in so-called re-forming reactions carried out in petroleum refineries. For example, the formation of filamentous carbon on such solids at temperatures in the same range as that used by Czerwosz et al. was reported by McCarthy in 1982 [115]. However, these authors did not analyze the carbon deposits by Raman spectroscopy, nor were they aware of the existence of fullerenes. Their concern was the removal of these carbons by steam or by combustion, because these carbons inactivated the catalyst. It was also unknown to them that these carbons had the lubricating properties that were demonstrated by Lauer and co-workers [60,62]. By using these catalysts under conditions of continuous wear, they could maintain the catalytic effect of the surface. 

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