API Gravity, Sulfur Content, and Desulfurization of Crude Oil

In this review, strategies for crude oil desulfurization are evaluated by reviewing desulfurization literature. The most important characteristics of crude oil that affect the market price are its sulfur content and gravity. Low sulfur content of crude oil is particularly preferred. Petroleum includes crude oil, natural gas, and heavy oil. Petroleum refineries convert crude oils and other input streams into dozens of refined (co)products. Two properties are especially useful for quickly classifying and comparing crude oils: API gravity (a measure of density) and sulfur content. Sulfur is naturally present as an impurity in fossil fuels. The removal of organosulfur compounds from crude oil is an important aspect of all countries to reduce air pollution. The sulfur compounds from gasoline are generally removed by treatment with an alkaline solution sodium plumbite. At large scales, the most economical technology for converting hydrogen sulfide into sulfur is the Claus process. This well-established process uses partial combustion and catalytic oxidation to convert about 97% of the H2S to elemental sulfur.