Pentene hydrocarbon mixtures

Olefins (n-Cg) from mixtures containing Cg branched olefins and cyclic hydrocarbons Silicalite-1 Pentene, 1-butene [163]... 

It was observed that 4,4-dimethyl-2-pentene was more readily oxidized than the saturated hydrocarbon—2,2-dimethylpentane—although the latter gave a significantly larger ion yield. In the case of this olefin, which was used as the stereoisomeric mixture, the cis and trans isomers were equally attacked in terms of hydrocarbon oxidized. 

A series of runs were made in which sulfuric acid was added in small increments to a 4 1 mixture of isobutane and 2.2,4-trimethyl pentene-1 at -30 C or -20 C. Increased amounts of the feed isoolefin reacted as more acid was added. Almost no reaction products were noted in the hydrocarbon phase at A/0 ratios of 0.25 or less. When the A/0 ratio was increased to 0.5, C9 - C Q hydrocarbons were formed during a 1.5 hour period during which tYme most of the original isoolefin reacted. 

Figure 2 also gives the G-values of the various products in the radiolysis of mixtures of cyclopropane-propene. The maximum in the acetylene yield is at a cyclopropane molar fraction of 0.75 and in the ethylene yield at cyclopropane molar fraction of 0.25 indicating probably that they are produced in competing reactions of the same intermediate. The curve of the yields of isobutane, 4-methyl-1-pentene and 1,5-hexadiene indicate bimolecular reactions since none of them is formed in the pure components. Foldiak and Horvath" suggested that the formation of these hydrocarbons may be explained by combination reactions between the reactive intermediates existing in high steady state concentrations in the system, as in equations 48 and 49 ... 

Comparison of the composition of the reaction mixtures resulting from heating of starch alone and with glycine gave the following results. The content of aliphatic hydrocarbons (mainly cyclohexane) is lower in the process with glycine. The overall content of ketones also decreases, and, instead of 4-methyl-3-penten-3-one, 2-hydroxy-2-methyl-1,4-pyrone (maltol), and... 

The role of surface in the formation of products in hydrocarbon oxidation has been discussed frequently. Knox has suggested that in the oxidation of isobutane at about 575 K, isobutene is formed homogeneously, but that other products are formed in surface reactions of RO -. Barnard and Lee, however, find no pentenes in a shock-tube study of the oxidation of n-pentane at 925—1125 K, in which surface reactions should be unimportant, and suggest that this supports Pollard s view that conjugate alkene is formed at the vessel surface. This interpretation can be discounted because radical decompositions should dominate at these temperatures, particularly at the rather low O pressures used, so that coiuugate alkene would at most be a very minor product. Recently, studies of the addition of n-butane to slowly reacting mixtures of H + O at 753 K using... 

Diisobutylene obtained from the C4 hydrocarbon family is a mixture of 2,4,4-trimethyl-l-pentene and 2,4,4-trimethyl-2-pentene. There is currently only one U.S. producer, two producers in the far east, and two Europe an manufacturers. The cost of diisobutylene is 50-75% higher than the more simply obtained trimer (nonene) or tetramer (dodecene). 

There are two fresh feedstreams. One is methanol. The other is a mixture of C5 components that contains reactive isoamylenes plus other C5 paraffins, naphthenes, and olefins. This C5 stream typically comes from a petroleum refinery light-ends unit that separates light hydrocarbon components generated in catalytic cracking into various streams. Because the boiling points of aU of the C5 components are quite similar, it is uneconomical to separate out the isoamylene reactants from the other C5s. The C5 fresh feedstream contains 24 mol% reactive isoamylenes. The remaining components are pentanes and pentene (largely isopentane), which are inert in the TAME reaction. 

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