K factor (crude oil refining)

The K factor or characterization factor is a systematic way of classifying a crude oil according to its paraffinic, naphthenic, intermediate or aromatic nature. 12.5 or higher indicate a crude oil of predominantly paraffinic constituents, while 10 or lower indicate a crude of more aromatic nature. The K factor is also referred to as the UOP K factor or just UOPK.