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Hydroprocessing catalysts

Recent books by Magee and Dolbear and by Scherzer and Gruia are superb sources of technical information on hydroprocessing catalysts, which are also discussed in Chapters 9-12. The hydroprocessing catalyst business is big, with annual sales approaching US 800 million per year. The materials most commonly used to make these catalysts are shown in Table 7 and Table 8. [Pg.195]

Metals Major Use Activation Method Hydrogenation Acitivy [Pg.196]

Chemical reactions take place inside small pores, which account for most of the catalyst surface area. The diameters of these pores range from 75A to 85A for catalysts that process light and heavy gas oils. For catalysts that process residue, the average pore size ranges from 150A to 250A. [Pg.196]


Reclamation, Disposal, and Toxicity. Removal of poisons and inorganic deposits from used catalysts is typically difficult and usually uneconomical. Thus some catalysts are used without regeneration, although they may be processed to reclaim expensive metal components. Used precious metal catalysts, including automobile exhaust conversion catalysts, are treated (often by the suppHers) to extract the metals, and recovery efficiencies are high. Some spent hydroprocessing catalysts may be used as sources of molybdenum and other valuable metals. [Pg.174]

M0S2 is one of the most active hydroprocessing catalysts, but it is expensive, and the economical way to apply it is as highly dispersed material on a support, y-Al202. The activity of the supported catalyst is increased by the presence of promoter ions, Co " or Ni ". The stmctures of the catalysts are fairly well understood the M0S2 is present in layers only a few atoms thick on the support surface, and the promoter ions are present at the edges of the M0S2 layers, where the catalytic sites are located (100,101). [Pg.182]

J. Wood, L. F. Gladden 2003, (Effect of coke deposition upon pore structure and self-diffusion in deactivated industrial hydroprocessing catalysts), Appl.Cat. A General, 249, 241. [Pg.283]

However, residuum hydrotreating catalysts themselves are susceptible to irreversible deactivation caused by the accumulation of sulfided metal impurities. The gradual buildup of these impurities in the pores of a hydroprocessing catalyst causes plugging and deactivation. [Pg.49]

Eijsbouts, S., Life Cycle of Hydroprocessing Catalysts and Total Catalyst Management, In Hydrotreatment and Hydrocracking of Oil Fractions. 1999, Elsevier Science B. V New York, NY. pp. 21-36. [Pg.62]

Metrex A process for recycling spent hydroprocessing catalysts. Developed in 1993 by Metrex BV. [Pg.176]

Tops0e, H. Bartholdy, J. Clausen, B.S., Candia, R. results presented at the ACS symposium on Structure and Activity of Sulfided Hydroprocessing Catalysts, The Division of Petroleum Chemistry, Inc. Kansas City Meeting, Sept. 12-17, 1982. [Pg.93]

These cracking and H-addition processes also require catalysts, and a major engineering achievement of the 1970s was the development of hydroprocessing catalysts, in particular cobalt molybdate on alumina catalysts. The active catalysts are metal sulfides, which are resistant to sulfur poisoning. One of the major tasks was the design of porous pellet catalysts with wide pore structures that are not rapidly poisoned by heavy metals. [Pg.65]

This refinery process is used extensively to improve the quality and usefulness of petroleum products. Hydroprocessing can reduce unstable olefins to paraffins and can remove sulfer, nitrogen, and oxygen heteroatoms. Hydroprocessing also effectively reduces aromatics to naphthenes and/or paraffins. Various hydroprocessing catalysts are available for each specific hydroprocessing need. [Pg.17]

The 1970 s will see substantial reduction in the amount of higher sulfur residua moving into domestic fuel markets. If natural gas fuel supplies are adequate, these residua will be converted to more valuable light products. The development of hydroprocessing catalysts has proceeded to the point where it is certain that desulfurization, and perhaps hydrocracking, will be practiced on higher quality residua before the decade is over. [Pg.135]

A better understanding of the chemical nature of the metal compounds, the mechanisms of HDM reactions, and metal deposition phenomena would establish a basis for developing improved hydroprocessing catalysts and reactors. A goal of research in this area is to develop catalysts with greater metals tolerance and operational life in reactors. [Pg.97]

In Section III, commercial residuum hydroprocessing technology is discussed to establish the role and requirements of hydroprocessing in the overall refinery residuum conversion scheme. Commercial residuum hydroprocessing catalysts and residuum hydrodesulfurization (RDS)-hydrodemetallation (HDM) technology are reviewed briefly. [Pg.97]

In Section IV, the kinetics and mechanisms of catalytic HDM reactions are presented. Reaction pathways and the interplay of kinetic rate processes and molecular diffusion processes are discussed and compared for demetallation of nickel and vanadium species. Model compound HDM studies are reviewed first to provide fundamental insight into the complex processes occurring with petroleum residua. The effects of feed composition, competitive reactions, and reaction conditions are discussed. Since development of an understanding of the kinetics of metal removal is important from the standpoint of catalyst lifetime, the effect of catalyst properties on reaction kinetics and on the resulting metal deposition profiles in hydroprocessing catalysts are discussed. [Pg.97]

This section will focus on the various hydroprocessing technologies that have been commercialized or are in a pilot stage near commercialization. Reactor design characteristics that differentiate the technologies will be highlighted. Included in this section is an overview of the properties and applications of commercial residuum hydroprocessing catalysts. [Pg.134]

The variety of applications and the market growth potential have attracted numerous entries into the residuum hydroprocessing catalyst market, as indicated by the compilation of commercial vendors and catalysts in Table XXIII. Catalysts are available in an assortment of shapes, sizes, and formulations, but detailed information on catalytic metals, support composition, pore size, and pore size distribution is sketchy. [Pg.154]

Vanadium and Nickel Distribution Factors in Residuum Hydroprocessing Catalysts"- ... [Pg.199]

Fig. 40. Typical deactivation curve for residuum hydroprocessing catalyst. Arabian Heavy atmospheric residuum desulfurized to 1.10 wt. % product sulfur with a iV-in. extrudate catalyst (Tamm ei al., 1981). Fig. 40. Typical deactivation curve for residuum hydroprocessing catalyst. Arabian Heavy atmospheric residuum desulfurized to 1.10 wt. % product sulfur with a iV-in. extrudate catalyst (Tamm ei al., 1981).
Fig. 47. Pore size distribution characteristics of typical residuum hydroprocessing catalysts (Howell et ai. 1985). Fig. 47. Pore size distribution characteristics of typical residuum hydroprocessing catalysts (Howell et ai. 1985).
Hardin, A. H., Ternan, M., and Packwood, R. H., The Effects of Pore Size in MoOrCoO-A1203 Hydroprocessing Catalysts," CANMET Report 81-4E, Energy, Mines and Resources, Canada, 1981 see also ACS Prepr. Div. Petrol. Chem. 23, 1450 (1978). [Pg.254]

In a recent study of deactivated resid hydroprocessing catalysts [14] it was concluded that resid catalysts in some situations deactivate under coke control. In this study it was shown that predominantly coke deactivated catalysts had residual activities that were in line with what was expected from the data in Fig. 8, e.g, 12.4% C ( 18.3% on a fresh catalyst basis) reduces the HDS activity to 35%, and 17,5% C (25% C on a fresh catalyst basis) gave a reduction of HDS activity to 22% of fresh catalyst activity. [Pg.205]

Nitrogen can act as a poison for both hydroprocessing catalysts and fluid catalytic cracking (FCC) catalysts. Therefore, its presence complicates the conversion of shale oil to finished products. [Pg.31]

Catalysts currently employed in process development units for coal liquefaction are hydroprocessing catalysts developed for petroleum refining (5l6). They are composed of combinations of Mo or W with Co, Ni or other promoters dispersed on alumina or silica-alumina supports. When used in liquefaction, these catalysts deactivate rapidly f6-9i causing decreases in product yield and quality and problems with process operability. Thus the... [Pg.279]

Size characterization measurements have provided useful information on the importance of the hydroprocessing catalyst pore size distribution and on the effects of visbreaking and hydroprocessing on the residua molecular size distributions. It is apparent that asphaltenes and maltenes are not unique entities, but instead have considerable overlap in their size distributions. A complete study of the effects of processing conditions would require consideration of all components of a residuum. [Pg.154]


See other pages where Hydroprocessing catalysts is mentioned: [Pg.494]    [Pg.643]    [Pg.174]    [Pg.224]    [Pg.272]    [Pg.75]    [Pg.190]    [Pg.58]    [Pg.295]    [Pg.643]    [Pg.95]    [Pg.153]    [Pg.153]    [Pg.155]    [Pg.211]    [Pg.212]    [Pg.249]    [Pg.180]    [Pg.27]    [Pg.482]    [Pg.530]    [Pg.118]    [Pg.207]   
See also in sourсe #XX -- [ Pg.195 ]




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