Hydrocarbons high molecular weight

Chromasorb Hydrocarbons, high molecular-weight organic vapours, chlorinated organic compounds... 

Metals such as Fe, Co, Ni, or Ru on alumina or other oxide supports convert CO and H2 to hydrocarbons. Using different catalysts and reaction conditions either CH4, liquid hydrocarbons, high molecular weight paraffins, methanol, higher alcohols, olefins, and aromatics can be obtained, though rarely (with the exception of CFL, and methanol) with high selectivity. Hydrocarbons typically exhibit a Schulz-Flory type molecular weight distribution. 

American Petroleum Institute Research Project 42, "Properties of Hydrocarbons of High Molecular Weight," API, Division of Science and Technology, New York, 1966. 

Fischer-Tropsch reaction The catalytic reaction of hydrogen and carbon monoxide (synthesis gas ) to produce high-molecular weight hydrocarbons. 

A number of related reactions of hydrocarbons are catalyzed by acidic oxide types of materials. These include the cracking of high molecular weight... 

Cracking (Section 2 16) A key step in petroleum refining in which high molecular weight hydrocarbons are converted to lower molecular weight ones by thermal or catalytic carbon-carbon bond cleavage... 

Polyethylene. Polymerization of ethylene results in an essentially straight-chain high-molecular-weight hydrocarbon. 

Another type of soHd supetacid is based on perfluorinated resin sulfonic acid such as the acid form of Du Font s Nafion resin, a copolymer of a perfluorinated epoxide and vinylsulfonic acid or soHd, high molecular weight petfluotoalkanesulfonic acids such as petfluotodecanesulfonic acid, CF2(CF2)qS02H. Such sohd catalysts have been found efficient in many alkylations of aromatic hydrocarbons (225) and other Friedel-Crafts reactions (226). 

Several biomass species have been found to contain oils and/or hydrocarbons (Table 13). It is apparent that oil or hydrocarbon formation is not limited to any one family or type of biomass. Interestingly, some species in the Euphorbiaceae family, which includes Hevea bra liensis form hydrocarbons having molecular weights considerably less than that of natural mbber at yields as high as 10 wt% of the plant. This corresponds to hydrocarbon yields of about 3.97 mVhm2-yr(25bbl/hm2-yr). 

Other high molecular weight hydrocarbon polymers are not biodegradable, but oligomers of <7j -l,4-isoprene (83), butadiene (84), and styrene (85), are degradable. And there has been further confirmation of biodegradation of oligomeric ethylene (86). 

Asphalt [8052-42-4] is defined by the American Society for Testing and Materials (ASTM) (1) as a dark brown to black cementitious material in which the predominating constituents are bitumens that occur in nature or are obtained in petroleum processing. Bitumen is a generic term defined by ASTM as a class of black or dark-colored (soHd, semisoHd, or viscous) cementitious substances, natural or manufactured, composed principally of high molecular weight hydrocarbons, of which asphalts, tars, pitches, and asphaltites are typical. 

Asphalts characteristically contain very high molecular weight molecular polar species, called asphaltenes, which are soluble in carbon disulfide, pyridine, aromatic hydrocarbons, chlorinated hydrocarbons, and tetrahydrofiiran. 

Caprolactam, mol wt 113.16, is a white, hygroscopic, crystalline soHd at ambient temperature, with a characteristic odor. It is very soluble in water and in most common organic solvents and is sparingly soluble in high molecular weight aUphatic hydrocarbons. Molten caprolactam is a powerful solvent for polar and nonpolar organic chemicals. Selected physical properties and solubiUties of caprolactam are Hsted in Tables 1 and 2, respectively. 

Relatively high steam requirements to desorb high-molecular-weight hydrocarbons... 

The development of oil-extended SBR in which a rubbery polymer of very high molecular weight is blended with substantial amounts of hydrocarbon oil. This provides a lower cost alternative to a polymer of more conventional average molecular weight. 

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