North African crude

Europe. The demand for naphtha for petrochemical feed purposes in Europe continues to rise strongly. As a result, the prices for this commodity have risen over the past several years. Increased use of light North African crudes, providing a higher proportion of gasoline and potential petrochemical naphtha, has retarded but not stopped the rise in naphtha prices. 

The most abundant heteroatom is invariably sulfur, appearing in concentrations from below 0.1 wt. % in North African or Indonesian light crudes to over 5 wt. % in Venezuelan heavy crudes (Boscan) or Canadian tar sands. A wide variety of sulfur containing compounds are present in petroleum and refinery fractions, ranging from thiols to thiophenes the most important classes of organosulfur compounds of interest for our purposes are represented in Fig. 1.1. 

This concept of optimum aromaticity and the role of sulfur compounds as inhibitors were further established by a study by Bum and Greig (British Petroleum) of the oxidation of solvent extracted base stocks.18 They chose samples from a North African (Sahara) and three Middle East (Iran, Abu Dhabi, and Kuwait) crudes. The aromatic + heterocyclic (A + II) and paraffin + naphthene (P + N) components were separated by alumina chromatography from each base stock (Table 5.9 includes their composition and sulfur contents) and recombined in several ratios and the resistance of the blends to oxidation measured by the oxygen uptake method. 

Crude Source North African Middle East ... 

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