For catalytic cracking

Proportions correspond to the material balance for catalytic cracking in Figure 10.3 showing streams (l)(2)(3)(4) and (5). 

Mild hydrocracking prepares the feedstock for catalytic cracking or for the conventional lubricant production scheme. 

The question then lies in the selection of more appropriate feedstocks for these two processes. The cost of hydrocracking leads to selecting feedstocks that are the easiest to convert as for catalytic cracking, its flexibility and extensive capabilities lead to selection of heavier feedstocks. 

Two-Stage Crude Distillation (Atmospheric and Vacuum) The vacuum stage can be used alternately to produce heavy gas oil for catalytic cracking feed or raw lube distillate cuts for lubricating oil manufacture. 

Since the war the demand for gasoline, jet, and diesel fuels has grown, while the demand for heavy industrial fuel oils has declined. Furthermore, many new oil finds have yielded heavier crudes, therefore the need to convert residue components into lighter oils for feedstock for catalytic cracking. 

Murphree, E. V., et al. (194S). Improved Fluid Process for Catalytic Cracking. Transactions of the American Institute of CheinicaJ Engineers 41 19-20. 

Residues containing high levels of heavy metals are not suitable for catalytic cracking units. These feedstocks may be subjected to a demetallization process to reduce their metal contents. For example, the metal content of vacuum residues could be substantially reduced by using a selective organic solvent such as pentane or hexane, which separates the residue into an oil (with a low metal and asphaltene content) and asphalt (with high metal content). Demetallized oils could be processed by direct hydrocatalysis. 

Gulf HDS A process for hydrorefining and hydrocracking petroleum residues in order to make fuels and feeds for catalytic cracking. Developed by the Gulf Research Development Company. See also hydrodesulfurization. 

The fluidized-bed reactor was originally developed for catalytic cracking in petroleum... 

Castaneda, R., Corma, A., Eornes, V., Martinez-Triguero, J., and Valencia, S. (2006) Direct synthesis of a 9 x 10 member ring zeolite (Al-lTQ-13) a highly shape-selective catalyst for catalytic cracking. J. Catal., 238, 79-87. 

Zeolite Beta Structure, Activity, and Selectivity for Catalytic Cracking... 

Jacob, S.M., Voltz, S.M., and Weekman, V. (1976) A lumping and reaction scheme for catalytic cracking. AIChE Journal, 22, 701. 

The zeolite to matrix surface area ratio can be used for optimization of catalysts for catalytic cracking of atmospheric residues. For North Sea long residues this ratio should be as large as possible, but the ratio should not exceed an upper limit. For the main catalyst type (A) used in this investigation the upper limit of the ZSA/ MSA ratio was around 3.5. There is also a lower limit for the matrix surface area. If the matrix surface area is lower than this limit, the catalyst will not be able to crack all the heavy components in the residue feed, and the coke on the matrix will increase dramatically. This will prevent the catalyst from working properly. Different type of catalysts must be optimized individually, as well as different type of long residues. 

Recently, Takenaka et studied a series of base metal catalysts supported on various ceramic oxides for catalytic cracking of kerosene fuel. Yields of H2 and methane from a model kerosene fuel (52 wt% n-Ci2, 27 wt% diethylbenzene and 21 wt% t-butylcyclohexane) over various base metals at 600°C are shown in Figure 33. Ni/Ti02 showed the highest catalytic activity for the cracking reaction of kerosene fuel, and also maintained a better performance for the kerosene feed that contained benzothiophene. However, the catalytic performance of the... 

The rate equation, eqn. (3), has been simplified for catalytic cracking on the basis of various assumptions. When all components are strongly adsorbed, the term H KiPi in the denominator is much greater than 1 and can be omitted. Then the expression [212,219]... 

Linear free energy relationships for catalytic cracking... 

Calculated parameters for the compensation effects mentioned by Sinfelt (74) are given in Table III, D [for the dashed line in Fig. 5 of (74), eight metals] and Table III, E (the full line on the same graph, six metals). No acceptable obedience to Eq. (2) could be found in other Arrhenius parameters for catalytic cracking reactions on a group of different metals (151, 212, 213). 

The first catalysts used for catalytic cracking were acid-treated clays, formed into beads. In fact, clays are still employed as catalyst in some cracking processes (Speight, 1999). 

Phillips Petroleum Company discovered and developed the antimony metals passivation process in the early 1970 s, and successfully applied the process at its Borger, Texas heavy oil cracker (HOC) in 1976 (2). For catalytic cracking units with... 

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