Production of alkane

The nitro alcohols can be reduced to the corresponding alkan olamines (qv). Commercially, reduction is accompHshed by hydrogenation of the nitro alcohol in methanol in the presence of Raney nickel. Convenient operating conditions are 30°C and 6900 kPa (1000 psi). Production of alkan olamines constitutes the largest single use of nitro alcohols. 

Sulfur reacts with alkanes to either dehydrate (eq. 1), oxidize, forming carbon disulfide and hydrogen sulfide (eq. 2), or cyclize, forming thiophenes (eq. 3). The products of alkane sulfurization depend on the temperature, the time at the temperature, and the stmcture of the hydrocarbon (1). 

Dumesic has reviewed the aqueous-phase reforming of polyols to H2 and CO2 under milder conditions, i.e., 200-250 °C [43], He also showed the possibility to divert the reaction towards to production of alkanes by using an acidic support for the Pt or Pd reforming catalyst. 

As indicated in Chapter 8, the production of alkanes, as by-products, frequently accompanies the two-phase metal carbonyl promoted carbonylation of haloalkanes. In the case of the cobalt carbonyl mediated reactions, it has been assumed that both the reductive dehalogenation reactions and the carbonylation reactions proceed via a common initial nucleophilic substitution reaction and that a base-catalysed anionic (or radical) cleavage of the metal-alkyl bond is in competition with the carbonylation step [l]. Although such a mechanism is not entirely satisfactory, there is no evidence for any other intermediate metal carbonyl species. 

Another reported example of the carbon-carbon bond-forming reaction from alcohols is that of the indirect Wittig reaction, which utilizes an [IrCl(cod)]2/dppp/ CsCOs catalyst system and leads to the production of alkanes (Equation 10.24) [47]. 

Transition-metal-catalyzed carbonylations are of great importance in organic synthesis as a powerful tool to prepare a variety of carbony compounds. Among them, hydroformylation has been most extensively studied not only in the laboratory but also in industry. Industrial production of alkanals from 1-alkenes... 

As another variation, the production of alkanes can be accomplished by modifying the support with a mineral acid (such as HCl) that is co-fed with the aqueous sorbitol reactant. In general, the selectivities to heavier alkanes increase as more acid sites are added to a non-acidic Pt/alumina catalyst by making physical mixtures of Pt/alumina and silica-alumina. The alkane selectivities are similar for an acidic Pt/silica-alumina catalyst and a physical mixture of Pt/alumina and silica-alumina components, both having the same ratio of Pt to acid sites, indicating that the acid and metal sites need not be mixed at the atomic level. The alkane distribution also shifts to heavier alkanes for the non-addic Pt/alumina catalyst when the pH of the aqueous sorbitol feed is lowered by addition of HCl. The advantages of using a solid acid are... 

Reactions of more electrophilic SC12 with fluoroolefins under thermolytic conditions are not selective they always produce a mixture of sulfenyl and thiosulfenylchlorides, sulfides, and polysulfides, along with substantial amounts of products of alkane chlorination [135]. 

Alkanes react with oxygen, producing heat. This combustion can be observed in the burning of methane in home heating systems and in the gas ranges in many kitchens. The products of alkane combustion are always water and carbon dioxide. Here is a sample balanced equation for alkane combustion. 

Production of alkane and alkene from CO2 by a petroleum-degrading bacterium strain HD-1... 

Note. The presence of alkanes may be erroneous as there are no reported metabolic pathways for the production of alkanes within the skin, and it appears likely that their presence may arise from external contamination. In addition, Lampe and co-workers emphasised that the high triglyceride content of their stratum corneum sample was probably due to contamination by triglyceride rich subcutaneous lipids. 

Here again, the OH radical initiating the reaction is regenerated. In the mechanism shown, three molecules of NO are oxidized to N02 and an equivalent number of ozone molecules is subsequently formed. This raises the total number of product ozone molecules to six. Additional N02 and ozone arises from the photoxidation of formaldehyde, HCHO, produced from acetaldehyde, and from the photooxidation of the ketones occurring as products of alkane oxidation. 

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