Olefins fraction

Ethers result from the selective addition of methanol or ethanol to the isobutene contained in C4 olefin fractions. Ethers are used as components in gasoline because of their high octane blending value (RON and MON). 

While most isoprene produced today comes from the dehydrogenation of C5 olefin fractions from cracking processes, several schemes are used for its manufacture via synthetic routes. The following reviews the important approaches for isoprene production. 

A general rule-of-thumb is that the olefin fraction of the sample is one-half of its bromine number. 

Alkymax A process for removing benzene from petroleum fractions. They are mixed with light olefin fractions (containing mainly propylene) and passed over a fixed-bed catalyst, which promotes benzene alkylation. The catalyst is solid phosphoric acid (SPA), made by mixing a phosphoric acid with a siliceous solid carrier, and calcining. Invented in 1980 by UOP... 

Polynaphta Essence A process for making a linear olefin fraction for making methyl r-butyl ether to use as a fuel additive. Developed by IFP in 1996 replacing UOP s Catpoly process. 

RCH [Ruhrchemie] A process for increasing the octane rating of gasolines by catalytic isomerization of the olefin fraction, the double bonds migrating from the terminal positions. Developed by Ruhr Chemie in the 1940s. 

The olefinic fraction (70%) was predominantly a mixture of the three decalins [79], [80] and [81] in a 2 3 1 ratio and formed along with a diastereoisomeric mixture of cyclohexanols (30%). Moreover, the decalins were produced with enantiomeric excesses of 53%, 53% and 80%, respectively. It is significant that the (Z)-isomer of [83] is not a substrate for this antibody. 

In addition to the analysis of the thermal stability of the perchloric acid organic reaction media mixtures, a procedure was worked out to determine the fate of the perchloric acid by chlorine analysis of the batch, effluent streams, etc. Preliminary analyses on selected process samples showed no tendency for perchloric acid to concentrate in recycle material and therefore build up in the reactor. A total of less than 1% of the initial charge of perchloric acid (total chlorides calculated as perchloric acid) was found in the combined recovered acid-ester and olefin fractions. Less than 1 % of the initial charge of perchloric acid was found in the finished ester. The analytical method used was an oxygen bomb decomposition, followed by titration of chlorides with 0.0liV silver nitrate, using a recording automatic titrator. The eventual fate of the perchloric acid catalyst was... 

The process of obtaining alkyl sulphonate in an autoclave with a mixer has been studied. Basic reagents were water solution of sodium hydrosulfite 36-38% and industrial olefin fractions at 240-320 °C. NaN03 and oxygen from air were used as initiators of the reaction of free radicals. System factors are x, reaction time, h x2 temperature of reaction, °C x3 mole ratio of sodium hydrosulfite and olefin x3 mole ratio of NaN03 and olefin x5 volume ratio of N-propanol and olefin. System response is a yield of alkyl sulfonate as a per cent of theoretical yield. FRFE design... 

The olefin fraction of the feed gas crosses the membrane and reacts reversibly with silver ions to form a soluble silver-olefin complex... 

Scrubbing provisions of this unit are not shown in Figure 4 for simplicity. Low molecular weight a-olefins are sent to olefin fractionation, and the low molecular weight trialkylaluminum compounds and high molecular weight olefins are sent to a second growth reactor. 

Compounds such as ethers, tertiary amines, or dialkyl sulfides have been considered. A detailed study was made of the reaction between TEA and ethers to find an ether which would facilitate TEA-olefin fractionation, while leaving TEA still sufficiently reactive for use in subsequent reaction steps. 

Addition of Chlorex has the following main eflFects on TEA-olefin fractionation ... 

Hydrocarbon product distributions on the zeolite-supported catalyst are shown in Table 1. The product distribution did not change greatly after deposition at 400 C, but the olefin fraction obviously increased. The shift in selectivity of paraffins to olefins is attributed to be due to the reduced capacity of the deactivated catalyst 10 hydrogenate primary olefins to the con-espondiiig paraffins. Similar results were also obtained with the alumina-supported catalysts. 

The alkylation reaction of isobutane with a mixture of C4 linear olefins was carried out in liquid phase at temperatures between 25 and 80°C, and at 30 Kg/cm, in a fixed-bed reactor. The space velocity was WHSV = 1 ft referred to the olefins. The isobutane is premixed with the olefins. The molar ratio used in this study was 15. The C4 olefins fraction contains 38% 1-butene, 22% trans-butene, 14% cis-2-butene and 26 % isobutene. In order to analyze the products coming out of the reactor, a ten-loop valve was used to collect the sample to be analyzed after the mn. Products are analyzed by GC, using a 100 m squalane column. Prior to the reaction, catalysts were pretreated in-situ, heating up to 250 C in an air stream. 

Properties Liquid. D 0.770 (20/20C), boiling range 183-218C, bulk d 6.44 lb/gal (15.5). Combustible. Derivation Olefin fraction obtained from catalytic polymerization of propylene. 

Another class of sulphonates is the a-olefin sulphonates which are prepared by reacting linear a-olefin with sulphur trioxide, typically yielding a mixture of alkene sulphonates (60-70%), 3- and 4-hydroxyalkane sulphonates ( 30%), and some disulphonates and other species. The two main a-olefin fractions used as starting material are C 2 ie Fatty acid and ester sulphonates are produced... 

Arguably the most demanding antibody-catalyzed cationic cyclization thus far reported has involved the formation of the decalins 58,59, and-60 (Scheme 11) [64]. The fra s-decahn epoxide 61 hapten, a TS mimic, was immunized as a diastereomeric mixture. Monoclonal antibody HA5-19A4 emerged as the best catalyst for the cyclization of arenesulfonate 62. The olefinic fraction (70%) was predominantly a mixture of 58,59, and 60 with an enantiomeric excess of 53,53, and 80%, respectively, with a significant proportion (30%) of cyclohexanols. 

The raw materials for tertiary ethers are the alcohols, methanol or ethanol, and the C4 or C5 olefin fractions. Methanol and isobutylene react to form methyl te/t-butyl ether (MTBE), methanol and isoamylene form tertiary amyl methyl ether (TAME), ethanol and isobutylene form ethyl tert-butyl ether (ETBE), and ethanol and isoamylene form tertiary amyl ethyl ether (TAEE). 

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