Alkanes large-scale

If a drybox is not available, the preparation can also be carried out by use of a dry, unreactive solvent (typically an alkane) as a blanket against hydrolysis. This has been suggested in the patent literature as a method for the large-scale industrial preparation of Eewis acid-based ionic liquids, as the solvent also acts as a heat-sink for the exothermic complexation reaction [28]. At the end of the reaction, the ionic liquid forms an immiscible layer beneath the protecting solvent. The ionic liquid may then either be removed by syringe, or else the solvent may be removed by distillation before use. In the former case it is likely that the ionic liquid will be contaminated with traces of the organic solvent, however. 

For natural product syntheses involving alcohols to acids cf. 2.2 below for large-scale oxidations cf. 2.3.7 for oxidation of aldehydes to carboxylic acids cf alkanes, 4.1.1. 

Abstract This chapter covers oxidation of C-H and C-C bonds in alkanes. Section 4.1 concerns oxidation of C-H bonds aldehydes and other CH species (4.1.1), methylene (-CH groups) (4.1.2) and methyl (-CH ) groups (4.1.3). This is followed by the oxidation of cyclic alkanes (4.1.4) and large-scale alkane oxidations (4.1.5). Alkane oxidations not considered here but covered in Chapter 1 are hsted in Section 4.1.6. The final section (4.2) concerns oxidative cleavage of C-C bonds. 

The other major springboard for the fluorocarbon chemical industry was the "Manhattan Project to develop the atomic bomb. This required the large-scale production of highly corrosive elemental fluorine and uranium(VI) fluoride for the separation of the radioactive 235U isotope. Oils capable of resisting these materials were needed to lubricate pumps and compressors, and polymers were needed to provide seals. Peril uorinated alkanes and polymers such as PTFE and poly(chlorotrifluoroethylene) (PCTFE) proved to have the appropriate properties so practical processes had to be developed for production in the quantities required. In 1947 much of this work was declassified and was published in an extensive series of papers3 which described the fundamental chemistry on which the commercial development of various fluoro-organic products, especially fine chemicals, was subsequently based. 

Isomerization of straight-chain to branched alkanes also increases the octane number, as do alkylates produced by alkene-isoalkane alkylation (such as that of isobutane and propylene, isobutylene, etc.). These large-scale processes are by now an integral part of the petroleum industry. Refining and processing of transportation fuels became probably the largest-scale industrial operation. 

The problem of availability of suitable paraffinic feedstocks of low cost, which represent a potentially wide range of molecular weight, will soon be rectified. Linear alkanes of high purity will be available from petroleum on a large scale, as is evident from recent announcements by both chemical and petroleum companies of plans to build normal paraffin extraction plants (2, J, 8). 

Wacker oxidation, a catalytic conversion of alkanes with aerial oxygen to carbonyl compounds, and its potential for large-scale applications has been reviewed.220 Aerobic... 

Unfunctionalized alkanes are a major feedstock for large-scale synthesis of intermediates and monomers in the chemical industry. They occur as mixtures in natural gas and are produced by cracking of light or heavy oil fractions. Higher al-... 

The least expensive way to make alkenes on a large scale is by the catalytic cracking of petroleum heating a mixture of alkanes in the presence of a catalyst (usually aluminosilicates). Alkenes are formed by bond cleavage to give an alkene and a shortened alkane. 

Prior to this, maleic anhydride had been industrially manufactured by the oxidation of benzene over supported V2O5-M0O3 catalysts. In the late 1970s, when pollution laws that restricted benzene emissions came into effect, industry began to use the -butane route. The reaction is of great importance as it is the only industrial large-scale selective oxidation of alkanes currently in operation. It also involves the functionalization of an alkane, providing a use for this rather unreactive oil fraction. 

This may, in part, be due to this reaction being the only industrial large scale functionalization of an alkane currently in operation, and knowledge gleaned from vanadium phosphate systems can provide valuable information that can be applied to different alkane activation reactions. To this end a number of the publications have focused and continue to focus on a fundamental understanding of the catalyst active surface and the active site. In recent years, transient techniques such as the use of TAP reactors and in situ characterization studies have advanced the under-... 

Single-component adsorption equilibria on activated carbon of the n-alkanes Q-C4 and of the odorant tert-butyl mercaptan were measured at the operating conditions expected in a large-scale facility for adsorbed natural gas (ANG) storage. The experimental data were correlated successfully with the Adsorption Potential theory and collapsed into a single temperature-independent characteristic curve. The obtained isotherm model should prove to be very useful for predicting the adsorption capacity of an ANG storage tank and to size and optimize the operation of a carbon-based filter for ANG applications. 

In this paper we outline techniques used to isolate two specific classes of compounds as well as a general class separation method suitable for large scale production of fractions. The specific isolation schemes are devised to produce an alkane or a PAH-enriched fraction. The general scheme provides for rapid fractionation of whole samples into several broad chemical classes. 

A technique called "prepolymerization" is practiced with selected psd controlled catalysts used in slurry and gas phase processes. The catalyst is suspended in a suitable solvent (usually a C -C alkane) and exposed to cocatalyst, ethylene, and, optionally, comonomer and hydrogen under very mild conditions in a separate, smaller reactor (11). Prepolymerization is allowed to proceed until the original catalyst comprises 5-30% of the total weight of the composition. Prepolymerized catalysts have limited storage stability and are ordinarily introduced without delay to the large-scale reactor. Prepolymerization provides several advantages ... 

While sugar alcohols are not common, large scale, they may be used in bioconversions such as from glycerol. Methane, methanol and n-alkanes have been used in biomass production. 

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