Heavy gasoline

Eleven different groups of crude oils haye been defined according to the densities of their heavy gasoline cuts (100-200°C) and their residues with boiling points above 350°C as shown in Table 3.1. 

Crude oil base Speclflc gravity of heavy gasoline cut, Specific gravity of residue (BP > 350°C)... 

Cut Ught gasoline Heavy gasoline Kerosene Gas oil Residue Crude... 

Gas Light gasoline Heavy gasoline Kerosene Gasoil Atmos, re d. 

For example, in the case of light Arabian crude (Table 8.16), the sulfur content of the heavy gasoline, a potential feedstock for a catalytic reforming unit, is of 0.036 weight per cent while the maximum permissible sulfur content for maintaining catalyst service life is 1 ppm. It is therefore necessary to plan for a desulfurization pretreatment unit. Likewise, the sulfur content of the gas oil cut is 1.39% while the finished diesel motor fuel specification has been set for a maximum limit of 0.2% and 0.05% in 1996 (French specifications). 

The main feedstock for catalytic reforming is heavy gasoline (80 to 180°C) available from primary distillation. If necessary, reforming also converts byproduct gasoline from processes such as visbreaking, coking, hydroconversion and heart cuts from catalytic cracking. 

Product properties Light gasoline Heavy gasoline Diesel oil Residue... 

Selective absorption of durene from heavy gasoline (bp 150—225°C) is possible using a version of UOP s Sorbex technology where the X zeoHte is made selective for durene by replacing the exchangeable sodium cations with lithium ions (16). 

Mitteiasien, n. Central Asia, mittelbar, a. indirect, mediate. Mittel-bauchgegend. /. mesogastric region, -benzin, n. medium benzine, medium-heavy gasoline or petrol, -binder, m. mediumsetting cement. 

Schwer-benzin, n. heavy gasoline (boiling over 100-120° C.), heavy petrol, -benzol, n. heavy benzol (boiling at about 160-200° C.). -betrieb, m. heavy operation, heavy duty, -blelerz, n. plattnerlte. 

Heavy naphthas 180-380 T 82-193°C Heavy gasoline Catalytic unit feed... 

A gas processing plant selectively extracts ethylene and ethane from an incoming natural gas mixture stream. These two light hydrocarbons are absorbed in a heavy gasoline type absorber oil, and then stripped with open steam in an open tower. The system data are (see Figure 8-41) ... 

A number of refiners split the debutanized gasoline into light and heavy gasoline. This optimizes the refinery gasoline pool when blending is constrained by sulfur and aromatics. In a few gasoline splitters, a third heart cut is withdrawn. This intermediate cut is low in octane and it is processed in another unit for further upgrading. 

A side stream is withdrawn at the tenth tray from the top of T-2 and proceeds to steam stripper T-3 equipped with five trays. Steam is fed below the bottom tray. The combined steam and oil vapors return to T-2 at the eighth tray. Stripper bottoms are pumped with J-6 through E-2A (on crude) and E-2B (on cooling water) and to storage as heavy gasoline. ... 

Most of the total gasoline yield loss, both for 40 S/A and 525 S/A, is found in the heavy gasoline (265-430°F). Table III shows this loss to be spread throughout the carbon number range of this fraction, due in large part to a reduction in paraffins as indicated by a higher ratio of aromatics to paraffins. This increased aromaticity contributes to higher octane. 

HC = Hydrocarbons CO = Carbon monoxide NO = Nitrogen oxide MTBE = Methyl tert-butyl ether T90 = the temperature at which 90% of the fuel s mass has been evaporated by distillation. The decrease in the heavy gasoline components, C8 to C9 alkanes and C6 to C, aromatics and alkenes... 

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