An Expression for the Average Molecular Weight of Diesel Fuels

This paper presents a simple expression for predicting the average molecular weight of diesel fuels. The expression consists only of the refractive index, volumetric average boiling point and density of a diesel fuel. Comparative evaluation of the expression is made against the most accurate and consistent method of Twu for the prediction of molecular weight of petroleum and coal-tar liquids. The predicted molecular weights for diesel fuels with refractive index, from 1.4585 to 1.5520 are essentially equivalent to or better than those obtained by any other method.