Alicyclic hydrocarbons paraffin

Alicyclic hydrocarbons are major components of petroleum (comprising from 20% to 67% of its volume) as well as components of plant oils and paraffins, microbial lipids, and pesticides. They range from simple molecules (e.g., cyclopentane and cyclohexane) to complex molecules (e.g., the pesticides aldrin and kepone shown in Figure 9.4). 

Several modified procedures have been described whereby excellent yields of paraffins, alkylbenzenes, and alicyclic hydrocarbons have been... 

The dependence of the aromatics/paraffin (or alicyclic hydrocarbon) separation factor on the activity of the hydrocarbon component being separated is not considered in detail in this chapter. This dependence can be non-monotonic as a result of membrane swelling. This issue deserves separate consideration. It should only be pointed out that such regularities are similar to those observed in hydrophilic membranes in selective separation of water from organics to water mixtures. The separation factor of hydrophilic membranes is strongly dependent on water activity in the feed mixture, and this dependence can be nonmonotonic as a result of membrane swelling [55]. 

The yields of paraffins and alicyclic hydrocarbons are poor, and the products are frequently contaminated with olefins. Aromatic ketones are reduced in much better yields. 

From these simple gas products, which correspond to a very large portion of the reacted feed stock, two basic cracking patterns are postulated the first is applicable to aliphatics and alicyclics (I) (thus including paraffins, olefins, and naphthenes), the second to substituted aromatics (II). These two basic patterns are best illustrated by Figures 1 and 2, which show the molar distribution of the principal cracked products according to the number of carbon atoms in the fragments, per 100 moles of feed stock cracked, for selected representatives of the four major hydrocarbon classes, all at 500° C. (see Table II for experimental conditions and product analyses). 

The virgin bitumen and fractions were characterized by 13C NMR. Results shown in Figure 1 show that the spectra of the maltenes and the virgin bitumen are virtually superimposable. The high resolution spectra reveal several resolved peaks in the saturates region attributable to n-alkyl species, some of which are of notably lower intensity in the maltenes spectrum, but in general, the vast majority of the saturates carbon (>80%) is found under the envelope and is probably due to complex alicyclic and/or isoparaffin structures. These results are consistent with an earlier observation (1) that saturated hydrocarbons from Uinta Basin bitumen are high in naphthenes and low in free paraffins. 

There are a number of classifications analogous to those of hydrocarbons (1) paraffinic or simple alcohols, whose formula may be represented as CnHa+1 (2) olefinic or fatty alcohols that contain one or more double bonds (3) alicyclic alcohols, closed-ring structures that may or may not contain a double bond, e.g., cyclohexanol (4) aromatic alcohols in which the hydroxyl group is attached to a benzene... 

The literature of the commercial development of hydrocarbons derivable from petroleum and natural gas is meager until about 1935. Since 1945, the literature has become extensive. This study includes the paraffins, olefins, alicyclics, aromatics, acetylene, and separation processes. Journals and sections of journals of value are discussed. The main subject heads to be consulted in Chemical Abstracts are given. There is considerable overlapping of subject matter in the U. S. patent classification system pertinent classes are listed. References in the bibliography were selected to show the various types available. 

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