Catalytic hydrotreating

Takeuchi, C. Fukui, Y. Nakamura, M., and Shiroto, Y., Asphaltene Cracking in Catalytic Hydrotreating of Heavy Oils. 1. Processing of Heavy Oils by Catalytic Hydroprocessing and Solvent Deasphalting. Ind. Eng. Chem. Proc. Des. Dev, 1983. 22(2) pp. 236-42. 

LT Unibon A two-stage, catalytic hydrotreating process for removing deleterious components from naphtha without cracking it. Developed by UOP. 

Trickle-bed reactors are used in catalytic hydrotreating (reaction with H2) of petroleum fractions to remove sulfur (hydrodesulfurization), nitrogen (hydrodenitrogena-tion), and metals (hydrodemetallization), as well as in catalytic hydrocracking of petroleum fractions, and other catalytic hydrogenation and oxidation processes. An example of the first is the reaction in which a sulfur compound is represented by diben-zothiophene (Ring and Missen, 1989), and a molybdate catalyst, based, for example, on cobalt molybdate, is used ... 

Fig. 14. Effect of decationizing pretreatment on the liquefaction, (a I) First-stage noncata-lytic hydrogen-transferred Morwell coal in the two-stage hydrotreatment (4(X)°C-10 min, 20 atm N>, tube bomb and molten tin bath, rapid heating) 4HFI/coal = 3.0g/3.()g. (a2) Second-stage catalytic hydrotreated Morewell coal in the two-stage hydrotreatment (400°C-20 min, 50 cc autoclave, slow heating).

Starch and Bakelite were obtained from stock supplies and were used as-received for pyrolysis studies of blends. Hydrogenated creosote was prepared in the laboratory by catalytically hydrotreating a 270°-355°C. creosote fraction to remove all heterocyclic impurities and to saturate completely the ring systems. 

Oil condensed from the released volatiles from the second stage is filtered and catalytically hydrotreated at high pressure to produce a synthetic cmde oil. Medium heat-content gas produced after the removal of H2S and C02 is suitable as clean fuel. The pyrolysis gas produced, however, is insufficient to provide the fuel requirement for the total plant. Residual char, 50—60% of the feed coal, has a heating value and sulfur content about the same as feed coal, and its utilization may thus largely dictate process utility. 

Transition metal sulphides are able to catalyze a very large number of reactions. The most important utilization concerns catalytic hydrotreating, but many others can be foreseen due to the resistance of these catalysts towards sulphur. For example, recent studies have demonstrated the interest of such catalysts for the selective conversion of carbon monoxide into hydrocarbons [1] or alcohols [2]. Until now, only few papers and patents report on the utilization of sulphides for fine chemical applications [3-6]. Nevertheless, this type of solids fits well to catalyze the reactions dealing with sulphur containing molecules. 

Benson, D. B., Berg, L., Catalytic Hydrotreating of Shale Oil, Chem. 

Catalytic Hydrotreating of Coal Derived Liquids, Project Seacoke Phase II Final Report, Prepared for Office of Coal Research by Arco Chemical Co., Contract No. 14-01-0001-473, Dec., 1966. 

Our research involved the investigation of catalytic hydrotreating in supercritical media. 

This investigation consisted of essentially two parts. The first involved a feasibility study of catalytic hydrotreating in the presence of supercritical fluid. The second part of our investigation involved the parametric studies to see how reaction parameters affect supercritical hydrotreating. 

SCANfining A selective catalytic hydrotreating process for reducing the sulfur content of naphtha. Developed by ExxonMobil and Albemarle. The catalyst, developed by ExxonMobil and Akzo Nobel, contains cobalt and molybdenum. The key feature is its prevention of the mercaptans reversion reaction — the formation of mercaptans from olefins and hydrogen sulfide. The process also minimizes olefin saturation and hydrogen loss. To be used at the Bazan Oil Refinery, Israel, from 2001, and at the Statoil refinery at Mongstad, Norway. Also planned for use in the Williams refinery in Memphis, TN. 

TABLE 10.13 Estimated Simple Rates of Return for Production of Substitute Diesel Fuels and Additives from Triglycerides and Tall Oils in an 80-mVday Catalytic Hydrotreating Facility ... 

Crude oil contains a number of elements other than carbon and hydrogen, which produce severe environmental impacts and must be removed. [1, 2] The principal method of their removal is catalytic hydrotreating. Many of the important crude oils have sulfur contents 1-6% by weight and nitrogen up to one percent. Ttic most important metals are vanadium and nickel, which may be as high as 1000 parts per million. These elements tend to be much more concentrated in the heavier portions in the crude oil, particularly in the residuum after distillation atmospheric resid boils above 650° F and vacuum resid boils above 1020° F. The process of hydrodesulfurization (HDS) is often carried out in parallel or in series with the process of hydrodemetallation (HDM). 

Sajkowski DJ, Oyama ST (1996) Catalytic hydrotreating by molybdenum carbide and nitride Unsupported Mo N and Mo C/Al O Appl. Catal A 134 339... 

The operating conditions for catalytic hydrotreating depend on the particular heavy end and the severity of the transformation required. Temperatures of the order of 375-430 C and pressure in the range 500-2000 psig are not uncommon. Recycle of hydrogen is a normal feature of industrial operations. 

In petroleum hydrotreating, both vapor phase and trickle bed reactors are used for catalytic hydrotreating of petroleum fractions. Under normal processing conditions, naphthas are completely in the vapor phase while higher boiling fractions are hydrotreated in a mixed-phase trickle bed reactor. These two types of catalytic reactors are discussed extensively. 

D. C. McCulloch, Catalytic hydrotreating in petroleum refining. In B. E. Leach, editor, Applied. Industrial Catalysis, volume one, pages 69-121. Academic Press, New York, 1983. 

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