Hexane insolubles, conversion

It has been known for some time that the yields of desirable products from coal liquefaction can be enhanced by dispersing the hydrogenation catalyst into the coal. For example, in the liquefaction of a high volatile bituminous coal, the total conversion to tenzene-soluble material, the asphaltene (hexane-insoluble), and oil yields were all enhanced when the catalyst was impregnated into the coal rather than mixed with the coal as a dry powder (2). In that work, impregnated salts of iron. 

The products were solvent fractionated into hexane soluble (HS), hexane insoluble-benzene soluble (HI-BS), and benzene insoluble (Bl) fractions. The yields of these solvent-fractionated products after hydrotreatment of SRC are plotted against the reaction time in Fig. 13. The overall activities of the catalysts were very similar to those of the commercial catalyst in spite of their lower surface areas. Both exploratory catalysts (Cat-A and Cat-B) showed similar reaction profiles, which were markedly different from those of the commercial catalyst. The BI fraction decreased over the exploratory catalysts equally as well as the over the commercial catalyst. However, the HS fraction hardly increased as long as the BI fraction was present. As the result, the HI-BS fraction increased to a maximum just before the BI fraction disappeared and then rapidly decreased to complete conversion after about 9 hr. The rate of HS formation increased correspondingly during this time. Thus, the exploratory catalysts were found to exhibit a preferential selectivity for conversion of heavier components of SRC, compared to the commercial catalyst. These results emphasize that the chemical and physical natures of the support are important in catalyst design (49). 

Coal-Derived Asphaltenes. Asphaltenes, operationally defined as the fraction of a coal liquefaction product that is soluble in benzene and insoluble in pentane (or hexane), are considered by many to be key intermediates in the conversion of coal to oil-like products (43, 44). Recently it was reported that coal-derived asphaltenes consist of... 

Example Glucose, C6H12O6, has five -OH groups capable of forming hydrogen bonds. It is expected to be soluble in hydrogen-bonding solvents such as water. Conversely, it should be insoluble in nonpolar solvents such as hexane. 

The TEMPO-catalyzed oxidation of alcohols to carbonyl compounds with buffered aqueous NaOCl has found broad apphcation even in large-scale operations. Indeed, this selective methodology involves the use of safe and inexpensive inorganic reagents under mild reachon condihons. A supported TEMPO 7, which is soluble in CH2CI2 and acetic acid but insoluble in ethers and hexane, was prepared and proved to be an effective catalyst for the selective oxidahon of 1-octanol with various stoichiometric oxidants. When 7 was employed at 1 mol% as a catalyst with a stoichiometric amount of NaOCl, the aldehyde was obtained in 95% yield after only 30 min of reaction. The recycling of catalyst 7 was shown to be possible for seven reaction cycles in the oxidahon of 1-octanol, that occurred in undiminished conversion and selectivity under similar reachon conditions. 

A suspension of commercial titanium powder (325-mesh) (2.06 g, 43 mmol) in DME and chlorotrimethylsilane (TMSCl) (6 mL) was refluxed for 48 h under Ar. A solution of diketone 11 (298 mg, 0.584 mmol) in DME (8 mL) was added at once and reflux was continued until TLC showed complete conversion of the substrate (ca. 8 h). The slurry was cooled to ambient temperature, diluted with THE (20 mL), and filtered through a pad of silica, the insoluble residues were washed with THE (20 mL in several portions), the combined filtrates were evaporated, and the crude product was purified by flash chromatography (silica, hexanes/ethyl acetate = 2 1) to afford product 15 as colorless, hygroscopic crystals (158 mg, 57%), m.p. (DSC) = 184.6 °C. 

When small amounts of water were deliberately added to butylhthiiun in hydrocarbon solution, it was possible to prepare polystjrrene with as much as 85% polymer that was insoluble in refluxing methyl ethyl ketone and identified as isotactic polystyrene by x-ray crystallography (164). Isotactic polystyrene (10-22% crystalline) can be prepared when lithium f-butoxide is added to w-C4H9Li initiator and the polymerization in hexane (styrene/hexane = 1) is effected at —30°C (165). This polymerization becomes heterogeneous and is quite slow (after 2-5 days, 50% monomer conversion 20-30% conversion to isotactic polymer). 

Reactions.—Replacement of halogen atoms in alkyl halides with hydrogen can often be achieved by trialkyltin hydride reduction. Two new work-up procedures" "" are said to simplify removal of the organotin halide by-product residues, either by their partition between hexane and acetonitrile " or by their conversion into insoluble polymeric organotin fluorides." ... 

In the sluny process/ a solution of about 2-6 wt% of the monomers in solution in a hydrocarbon such as isobutane, n-pentane or n-hexane is slurred with the catalyst, and the polymerization proceeds in a loop reactor achieving conversions 97%. Typical co-monomers with ethylene can be butene-1, hexene-1, 4-methylpentene-1, and octene-1. The catalyst is suspended in the solution, which is then pumped as turbulent slurry through relatively narrow tubes. The polymer is essentially insoluble in the liquid diluent and forms a sluny containing up to 30 wt% of small polymer particles, which are removed continuously. 

These rapid systems are used predominantly for (adiabatic) polymerizations below the melting point of PA 6. These cases allow one to prepare PA6 (97% conversion) with more than 40% crystaUtnity, often with both a and y phases. If difunctional NCL are used, for example, l,6-di(carbamoyl-e-caprolactam)hexane, HDICL18, the polymer product contains up to 80% of gel (insoluble in CF3CH2OH), which improves the mechanical properties [16, 17, 40]. 

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