Feedstocks production

Etliylene production involves liigh temperatures (1500°F) in tlie pyrolysis section and cryogenic temperatures in tlie purification section. The feedstocks, products, and by-products of pyrolysis are flaimnable and pose severe fire liazards. Benzene, wliich is produced in small amounts as a byproduct, is a known carcinogen. Table 21.7.1 summarizes some of the properties of etliane (feedstock) and tlie product gases. Figure 21.7.1 shows a simplified schematic diagram of the pyrolysis and waste heat recovery section on an etliylene plant. 

Dextran is the first microbial polysaccharide produced and utilized on an industrial scale. The potential importance of dextran as a structually (and property) controlled feedstock is clearly seen in light of the recent emphasis of molecular biologists and molecular engineers in the generation of microbes for feedstock production. Dextran is employed as pharmaceuticals (additives and coatings of medications), within cosmetics, as food extenders, as water-loss inhibitors in oilwell drilling muds and as the basis for a number of synthetic resins. 

To our knowledge, none of the developed SLP and SAP catalysts made their way into a technical process. Obviously, the possibility of using a supported liquid catalyst in a continuous liquid phase reaction is generally very restricted. The reason is that a very low solubility of the liquid in the feedstock/product mixture is enough to remove the catalyst from the surface over time (due to the very small amounts of liquid on the support). Even worse, the immobilised liquid film can be removed from the support physically by the mechanical forces of the continuous flow even in the case of complete immiscibility. 

Figure 14.18 shows the average specific hydrogen costs (including feedstock, production, transport and refuelling), and the cumulated investment in hydrogen infrastructure aggregated for all countries for the FlyWays base case scenario. 

The analyses considered here are based on various feedstock, products and process routes. 

The evaluation of petroleum must of necessity involve a study of composition because of the interrelationship of the physical properties and composition as part of the overall evaluation of different feedstocks. There are several ASTM procedures for feedstock/product evaluation ... 

Chapters 1 through 6 outline our understanding of the enzymes necessary or potentially useful for biomass conversion. Included are chapters on fuels and chemical feedstock production, pulp and paper processing, waste processing and degradation, food processing, and specific classes of alkali or thermostable enzymes. 

The energy intensity of the processes contributes to the energy payback time of modules. Current silicon feedstock production is energy intensive, around ISOkWhkg . Together with the low silicon utilization, this leads to a module energy payback time between 1.5 and 4 years, which, although much shorter than the module lifetime, needs to decrease. 

Finally, the product slate (e.g. olefin production, petrochemical feedstock production), or the product quality (e.g. gasoline octane improvement) may dictate a reduction in rare earth usage. 

Basic data for the two industrial units and the characteristics of their feedstock, products and catalyst... 

There are several ASTM procedures for feedstock/product evaluation. These are ... 

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