This method is for calculating the UOP Characterization Factor of petroleum oils from API gravity and distillation or viscosity data. Average molecular weight of petroleum oils is estimated from API gravity and distillation data. The UOP Characterization Factor, commonly called K, is indicative of the general origin and nature of a petroleum stock. Values of 12.5 or higher indicate a material predominantly paraffinic in nature. Highly aromatic materials have characterization factors of 10.0 or less.
ASTM UOP375-86 history
2007ASTM UOP375-07 Calculation of UOP Characterization Factor and Estimation of Molecular Weight of Petroleum Oil
2002ASTM UOP375-86 Calculation of UOP Characterization Factor and Estimation of Molecular Weight of Petroleum Oils