Product hydrocracking

Fuel octane number, 72 392, 395 Fuel oil, as a petroleum product, 78 669 Fuel oil additives amine oxides, 2 473 fatty amines, 2 534 Fuel properties, of ethers, 70 574 Fuel sources, chemical industry, 70 136 Fuel spills, hydrazine, 73 588 Fuels production, hydrocracking for, 76 842-844 Fuel sulfur, 70 54... 

Hydrogen is also important in fuel production. Hydrocracking uses the partial pressure of hydrogen gas to break down complex organic molecules, and forms by-products such as ethane, aromatics, and jet fuels. Liquid hydrogen is also used as a rocket fuel. In fission-based nuclear reactors, heavy water (where deuterium replaces regular hydrogen) is used as a neutron moderator. 

Hydrotreating and hydrocracking differ in other ways. For a given amount of feed, hydrocrackers use more catalyst and operate at higher pressures. They also use different catalysts. Because they make large amounts of light products, hydrocracker fractionation sections must be more complex. In some hydrocrackers, unconverted oil from the fiactionation section is recycled, either back to the front of the unit or to a separate cracking reactor. 

Catalyst selectivity is a measure of the rate of formation of a desired product relative to the rate of conversion of the feed (or formation of other products). Hydrocracking selectivity is expressed as the yield of desired product at a specific conversion. Yield is determined by the rate of formation of the desired product relative to the feed rate. At 100% conversion, catalyst yield equals catalyst selectivity. Hydrocracking selectivity is affected by operating conditions. In general, more severe operating conditions cause higher selectivity for secondary products. 

Eemandes, E.A.N., Teles, U.M., 2007. Modeling and optimization of Fischer—Tropsch products hydrocracking. Fuel Processing Technology 88, 207—214. 

Pellegrini, L., Locatelli, S., RaseUa, S., Bonomi, S., Calemma, V., 2004. Modeling of Fischer—Tropsch products hydrocracking. Chemical Engineering Sciences 59,... 

The experimental data of distillation curves of hydrocracked products obtained at the lowest LHSV (0.33 h ) at three reaction temperatures were used to determine the optimum set of parameters (5, a, Aq, a, and of the continuous kinetic model. Figure 11.6 shows the comparison between experimental and predicted distillation curves of the feedstock and the product hydrocracked at LHSV of 0.33 h" and 420°C. This plot is an example of the way the data are fed and reported by the MATLAB computer program as dimensionless curves. At 420°C, the optimum set of parameter values is a = 0.246, = 1.487, = 22.83, 8 = 1.67 x 10" , and... 

Feedstocks for this very flexible process are usually vacuum distillates, deasphalted oils, residues (hydrotreated or not), as well as by-products from other processes such as extracts, paraffinic slack waxes, distillates from visbreaking and coking, residues from hydrocracking, converted in mixtures with the main feedstock. 

The hydrocracking process is characterized by a very low gas production and a low LPG yield especially when operated for maximum distillates. Byproducts in this operating mode are ... 

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

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

Table 10.18 presents some useful data on the mild hydrocracking process and resulting products. 

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

Hydrocracking is a major process for the production of diesel motor fuel catalytic cracking is its counterpart for the gasoline production. 

Hennico, A., A. Billon, P.-H. Bigeard and J.-P. Peries (1993), IFP s new flexible hydrocracking process combines maximum conversion with production of high viscosity, high VI lube stocks . Rev. Inst. Fran. du Petrole, Vol. 48, No. 2, p. 127. 

In an effort to obtain higher value products from SRC processes, a hydrocrackiag step was added to convert resid to distillate Hquids. The addition of a hydrocracker to the SRC-I process was called nonintegrated two-stage Hquefaction (NTSL). The NTSL process was essentially two separate processes ia series coal Hquefaction and resid upgrading. NTSL processes were iaefficient owiag to the inherent limitations of the SRC-I process and the high hydrocracker severities required. 

Solvents. Petroleum naphtha is a generic term appHed to refined, pardy refined, or unrefined petroleum products. Naphthas are prepared by any of several methods, including fractionation of distillates or even cmde petroleum, solvent extraction, hydrocracking of distillates, polymerization of unsaturated (olefinic) compounds, and alkylation processes. Naphtha can also be a combination of product streams from more than one of these processes. 

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