Olefins conversion

T. Inui, "Stmcture-Reactivity Relationship in Methanol to Olefin Conversion on Various Microporous Crystalline Catalysts," paper presented at... 

Despite the utmost importance of physical limitations such as solubility and mixing efficiency of the two phases, an apparent first-order reaction rate relative to the olefin monomer was determined experimentally. It has also been observed that an increase of the nickel concentration in the ionic phase results in an increase in the olefin conversion. 

In the homogeneous Dimersol process, the olefin conversion is highly dependent on the initial concentration of monomers in the feedstock, which limits the applicability of the process. The biphasic system is able to overcome this limitation and promotes the dimerization of feedstock poorly concentrated in olefinic monomer. 

However, high conversions (82-91%) and high enantioselectivities (up to 90% ee) could be obtained in the cycUzation of the ( )-trisubstitued olefin 64 catalyzed by complex 61d (Scheme 41). hi this reaction neither solvent nor temperature has a significant effect on the enantioselectivity. In the case of the corresponding (Z)-trisubstituted olefins, conversions are high, but enantioselectivities are lower (ee < 36%). 

We looked at a number of water soluble cosolvents (Table 28.3). In all cases aldehyde products were observed. 1,4-dioxane compares well with ethanol as a co-solvent. The data so far shows that 1,4-dioxane shows slightly lower olefin conversion after two hours than ethanol, but shghtly better selectivity. 

Aqueous Phase Olefin Conversion Linear/B ranch... 

Catalytic activity. Figure 49.1 shows the catalytic activity of FePcCli6-S for the allylic oxidation of 1, 2, and 3. High olefin conversion was observed the highest ketone yield was obtained with cyclohexene. The lower ketone yields... 

Spectra of solution cast films of the hydrogenated NBR were recorded on a Nicolet 520 FT-IR spectrophotometer. The final degree of olefin conversion was confirmed by infrared analysis.9... 

OCT [Olefins conversion technology] A process for making propylene from mixed petrochemical feedstocks. Developed by Phillips and acquired by ABB Lummus Global in 1997. First installed at the Karlsruhe oil refinery of MineraloelrafFinerie Oberrhein (Miro) for startup in 2000. 

Run no. Catalyst Reactant Initial/ before H202 addition pH After H202 addition At die end of die reaction TOF Olefin conversion (mol%) h2o2 efficiency Epoxide selectivity (mol%)... 

Olefins, conversion to alcohols, 53, 94 from tosylhydrazones and methyllithium, 51, 69 hydroboration-oxidation of,... 

Liu et al. [18] investigated the possibility of catalyst recycling in the nonaqueous hydroformylation of 1-decene by using the thermomorphic polyether phosphite 2a described earlier under phase-transfer conditions. Catalyst recovery with the procedure of phase-separable catalysis was possible with 0.92% rhodium loss in the seventh cycle. Complete olefin conversion and aldehyde yields of 98% were reached, but linear and branched aldehydes were formed in almost equal amounts. 

Olefin conversion per pass can be as high as 60% with yields approaching 95%. (Conversion relates to how much ethylene disappears in one pass yield relates to how much of it ends up jn the finished product, not in the by-products. See the appendices for further discussion.)... 

The reactor effluent is fed to the spent catalyst separation section where catalyst is removed, treated to remove any volatile hydrocarbons, and sent to be regenerated. The effluent is then distilled to remove and recycle unreacted ethylene, then fractionated into high purity alpha olefins. The reaction solvent is also recovered for recycling. Olefin conversion per pass is 50—60%, with the combined yields of C4-C10 alpha olefins of 93%. 

Most of the catalytic interest in the AlP04-based molecular sieves have centered on the SAPOs which have weak to moderate Bronsted acidity, and two have been commerciahzed SAPO-11 in lube oil dewaxing by Ghevron and SAPO-34 in methanol-to-olefins conversion by UOP/Norsk Hydro. Spurred on by the success of TS-1 in oxidation catalysis, there is renewed interest in Ti, Co, V, Mn and Cr substituted AlP04-based materials, for a review of recent developments in the AlP04-based molecular sieves see [35]. 

The composition of the gasoline obtained by catalytic cracking and used as a feedstock for the ZSM-5 catalyst is given in Table VI. Product analyses, also given in Table VI, show that 80% of the olefins and less than 10% of the paraffins are converted by the ZSM-5 catalyst with about 30% of the olefin conversion attributable to the matrix present in the catalyst. This is not surprising due to the well-known higher reactivity of olefins. 

Light hydrocarbons (Ci to C4) and aromatics (mainly Ce to Ce) were produced by ZSM-5 due to the the conversion of olefins and paraffins. Thus,these results provide evidence for cracking of olefins, paraffins and cyclization of olefins by ZSM-5 at 500 C. The steam deactivated ZSM-5 catalyst exhibited reduced olefin conversion and negligible paraffin conversion activity. 

Supported iron porphyrins are less reactive than the corresponding manganese derivatives in the PhIO epoxidation of cyclooctene. 80% of olefin conversion was reached with MnBrgTMPS-PVP in 2 h, whereas only 10% was obtained with FeBrgTMPS-PVP in 6 h. 

At Van Sickle s conditions of low temperatures and low conversions, branching routes A and B appear to be dominant since there is little alkenyl hydroperoxide decomposition. In our work above 100°C., the branching routes are supported by the nearly linear initial portions at low conversions for alkenyl hydroperoxide and polymeric dialkyl peroxide curves (see Figures 2, 3, and 4). The polymeric dialkyl peroxides formed under our reaction conditions include those formed by the branching mechanism postulated by Van Sickle (routes A and B) and those formed by the reaction of the alkenoxy and hydroxy radicals from alkenyl hydroperoxide thermal decomposition reacting further and alternately with olefin and oxygen (step C). The importance and kinetic fit of the sequential route A to C appears to increase with temperature and extent of olefin conversion owing to the extensive thermal decomposition of the alkenyl hydroperoxides above 100°C. 

DSM370 has patented platinum systems based upon tetrasulfonated bidentate water soluble ligand 29 (Table 2 x=4, m=0, n=0) as catalysts for the hydroformylation of a mixture 1-butene (45%) and 2-butene (22%) with 33% butane at 100°C and 80 bar CO/H2 in an aqueous/methanol (300/32), CF3SO3H acidic medium. The olefin conversion was 86% and the selectivity to the aldehydes 95% (n/i ratio of 2.8) together with small amounts of aldolcondensation products and acids. The products were isolated from the aqueous catalyst mixture leaving the reaction zone by extraction with ether and the aqueous phase recycled to the reactor. 

Catalyst Temp. (°C) D2/olefin Conversion (%) Ethylenes Ethanes ... 

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