Feedstock compositions

Typical feedstock composition, yields and characteristics of effluents fron reforming and isomerization processes. j... 

Typical feedstock composition and product properties for the synthesis of MTBE-ETBE. 

Table 10.8 shows a typical feedstock composition and the average properties of crude or pure TAME. 

Typical feedstock composition used for tame synthesis. Product performance and properties. 

Table 10.9 Typical oligomerization feedstock compositions. Performance and product properties. ...

Typical steam cracking feedstock composition and yields. 

Table 10.16 gives a typical feedstock composition, as well as yields and product properties. 

Typical feedstock composition, yields and product properties for a hydrocracking unit (to be continued). 

Typical Feedstocks composition, performance and product properties from mild hydrocracking. I... 

Typical hydrotreating feedstock composition. Performance and product properties. 

Many agents have been proposed and patented including copper sulfate (34), zinc chloride (35), ferric chloride (36), aluminum chloride (36), and phosphoms pentoxide (37) ferric chloride, zinc chloride, and phosphoms pentoxide have been most widely used. The addition of these agents may vary from 0.1 to 3%, depending upon the feedstock and the desired characteristics of the product (Table 5) and all asphalt feedstocks do not respond to catalysts in the same way. Differences in feedstock composition are important qualifiers in determining the properties of the asphalt product. The important softening point-penetration relationship, which describes the temperature susceptibiUty of an asphalt, also varies with the source of the feedstock. Straight-reduced, air-blown, and air-blown catalytic asphalts from the same cmde feedstock also vary considerably. 

Catalysts intended for different appHcations may require their own unique types of reactor and operating conditions, but the key to designing a successful system is to use the same feedstock composition that is expected in the ultimate commercial installation and to impose so far as is possible the same operating conditions as will be used commercially (35). This usually means a reactor design involving a tubular or smaH-bed reactor of one type or another that can simulate either commercial multitubular reactors or commercial-size catalyst beds, including radial flow reactors. 

SELOP C4 A process for upgrading the C4 petroleum fraction by selective catalytic hydrogenation. Different catalysts, containing palladium on alumina, are used for different feedstock compositions. Developed by BASF and used in its Antwerp plant since 1994. 

When coal or biomass is heated, many reactions including dehydration, cracking, isomerization, dehydrogenation, aromatization, and condensations take place. Products are water, carbon dioxide, hydrogen, other gases, oils, tars, and char. The product yields vary, depending on the particular feedstock composition, particle size, heating rate, solids and gas residence times, and the reactor temperature. 

The catalyst is reported to be a true solid acid without halogen ion addition. In the patent describing the process (239), a Pt/USY zeolite with an alumina binder is employed. It was claimed that the catalyst is rather insensitive to feed impurities and feedstock composition, so that feed pretreatment can be less stringent than in conventional liquid acid-catalyzed processes. The process is operated at temperatures of 323-363 K, so that the cooling requirements are less than those of lower temperature processes. The molar isobutane/alkene feed ratio is kept between 8 and 10. Alkene space velocities are not reported. Akzo claims that the alkylate quality is identical to or higher than that attained with the liquid acid-catalyzed processes. 

The effects of reactor type, process variables and feedstock type, catalysts, and feedstock composition (Chapters 5 and 6) on the desulfurization process provide a significant cluster of topics through which to convey the many complexities of the process. In the concluding chapters, examples and brief descriptions of commercial processes are presented (Chapter 7) and, of necessity, some indications of methods of hydrogen production (Chapter 8) are also included. 

Fractionation of heavy feedstocks into components of interest and study of the components appears to be a better approach than obtaining data on whole residua. By careful selection of a characterization scheme it may be possible to obtain a detailed overview of feedstock composition that can be used for process predictions. 

There is, however, one aspect of feedstock properties that has not yet been discussed fully and that is feedstock composition. This particular aspect of the nature of the feedstock is, in fact, related to the previous section where the influence of various feedstock types on the hydrodesulfurization process was noted, but it is especially relevant when residua and heavy oils from various sources are to be desulfurized. 

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