Decalins composition

Improvement of dehydrogenation activities for decalin by carbon-supported composite catatysts under superheated Uquid-fihn conditions... 

AXB) shows time courees of amounts of evolved hydrogen and decalin conversions with caibon-supported platinum-based catalysts unda" supeiheated liquid-film conditions. Enhancement of dehydrogenation activities for decalin was realized by using fiiese composite catalysts. The Pt-W / C composite catalyst exhibited the hipest reaction rate at the initial stage, whereas the Pt-Re / C composite catalyst showed the second highest reaction rate in addition to low in sensitivity to retardation due to naphthaloie adsorbed on catalytic active sites [1-5], as indicated in Fig. 2(A) ). 

EfiSdent hydrogai supply firm decalin at modoate temperatures of below 250°C was acomplished by utilizing the superheated liqirid-film- pe catalysis under reactive distillation conditions in the present study. The composite catalysts in Ak liquid-film states improved dehydrogenation activities for decalin. 

The isotopic composition of the Decal ins in the spent solvents is indicative of the mechanisms of their formation. A total of 6 hydrogen atoms are added to the Tetralin to form Decal in. In E10, during the course of the experiment, the average protium concentration in the Tetralin increased from 2.3 to 21.3 atom % 1H. The protium content of 34 atom % 1H in the cis-Decalin was greater than the protium content in the Tetralin. Likewise in El9, the protium content in the Tetralin increased from 1.0 to 12.3 atom% H, while the cis contained 18.8 atom % 1H. This increase of pro-... 

An investigation of the isotopic composition of the Decal ins, which were formed as minor products in the donor solvent experiments, showed that cis-Decalin was formed preferentially. Its formation and its increased protiurn incorporation may have resulted from increased contact with the coal surface. Trans-Decal in contained less protiurn than the Tetralin, which suggests that most of the trans-Decalin was formed with deuterium from the Tetralin-di2 and deuterium gas. 

All solvents for these solution thermolysis reactions were freshly distilled and all reactions were done in sealed glass tubes heated in a thermostatted oven. Over a wide range of solvents (DMF, naphthalene, diphenylmethane, benzene, toluene, and decalin) there was no significant variation in either isomerization rate or product composition. Reactions were done at 125°C, 155°C and 195°C and the only limitation was that DMF could not be used as the solvent in reactions at 195°C it led to substantial substrate destruction (polymer forming reactions of substrate with DMF ). Isomer compositions were ascertained both by HPLC and by NMR. 

Another example is the thermal and photochemical cis-trans isomerization of Cp2Fe2(CO)2( -CO)( -Sip-TolH).25 In this case, both cis(H) and trans isomers can be isolated at full purity by flash chromatography. Interconversion between these isomers occurs both thermally and photochemi-cally in cyclohexane-d12, and the composition in the thermal equilibrium state (cis(H) trans = 2 98 at 25°C) is extremely different from that in the photostationary state (cis(H) trans = 70 30). Kinetics of the thermal isomerization in decalin afforded the activation parameters shown in Eq. (58). The large negative activation entropies imply that this reaction also... 

They have studied by low-angle X-ray diffraction21copolymers MMA-HMA in a selective solvent (acetonitril) and in a non-solvent (decaline) for the PMMA blocks and copolymers MMA-LMA and MMA-OMA in a preferential solvent (ethyl acetate) and in a non-solvent (octanol) for the PMMA blocks. The study in acetonitril solutions of a set of copolymers MMA-HMA with a PHMA block of constant length and with compositions in PHMA between 17 and 79% has shown that copolymers MMA/HMA exhibit, as a function of their composition in insoluble block, four of the five structures already observed for SB copolymers by X-ray diffraction and electron microscopy37,69,71> u namely cubic, hexagonal, lamellar and inverse hexagonal (Table 7). These copolymers may also present two structures as a function of the solvent concentration for some compositions (Table 7). 

Table V. Comparison of Product Composition from Hydropyrolysis (HP) and Thermal Cracking (TC) of Decalin (2)° d...

Table VI. Change in Product Composition from Hydropyrolysis of Decalin (2) as a Function of Reaction Temperature "0...

Mechanism of Decalin Hydropyrolysis. On the basis of some principles of the Rice-Kossiakoff free-radical theory (7-JO), the compositional changes summarized in Table VI and Figure 10 can be rationalized in terms of the following suggested mechanism for hydropyrolysis of 2 (Scheme 2) ... 

Cis- and frans-3-f-butyl (or 3-p-chlorophenyl) thietane 1-oxides are isomerized on treatment with hydrogen chloride in dioxane. Mixtures of varying isomer composition yield equilibrium mixtures consisting of 85-100% of the cis isomer. A similar result is obtained by heating the sulfoxides at 170-175° in decalin. Likewise, 3-methyl-3-phenylthietane 1-oxide may be isomerized to an equilibrium mixture consisting mainly (74%) of the equatorial, c/s-3-phenyl isomer. ... 

PE/i-PP blend films were prepared by gel crystallization from semidilute decalin solution as reported by Balta Calleja et al. (1990b), using ultra-high-molecular-weight PE (M2 = 6 X 10 ) and i-PP (M , = 4.4 x 10 ). In addition to the individual PE and i-PP homopolymer dry gels, Baltd Calleja et al. investigated PE/i-PP compositions of 75/25, 50/50 and 25/75. For all compositions a concentration of about... 

The typical sonochemical reaction is performed as follows a slurry of the MSP material, for example, Al-MCM-41, in decalin containing dissolved Mo(CO)6 and/ or Co(CO)3NO, is sonicated. The sonication is carried out under ambient air at room temperature. The solid product is separated by centrifugation, thoroughly washed with dry pentane, and dried in vacuum at room temperature. The chemical composition of the solid phase was determined by EDAX to probe whether the... 

Feed Catalyst Temp. (°C) Partially converted product, composition (%) Decalin stereoisomers, distribution (%) ... 

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