Boiling range of hydrocarbons

Figure 6-1 Boiling ranges of hydrocarbons with the boiling ranges of petroleum fractions also shown. 

Compared to SMDS, this simplified process employs a different catalyst in the synthesis stage and does not include a Heavy Paraffinic Conversion stage for producing the finished middle distillate fractions. The syncrude product is a broad boiling range of hydrocarbons (Table 4), and the relative amounts of individual products can be varied by adjusting the reaction conditions. Alternatively, syncrude products can be processed in existing refineries into finished transportation fuels. 

The ideal concept is usually a good approximation for close boiling components of a system, wherein the components are all of the same family of hydrocarbons or chemicals for example paraffin hydrocarbons. When odd or non-family components are present, the possibility of deviations from non-ideality becomes greater, or if the system is a wide boiling range of components. 

The hydrocarbons present are complex, but are principally paraffinic, naphthenic, and aromatic in composition. The complexity of the compounds present increases with the boiling range of the crude oil. 

Fig. 1. Relative quantities and boiling range of major hydrocarbon classes in the crude oil from Ponca City Field (Venuto and Habib, 1978).

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