Correlation of pour point of gas oil and vacuum gas oil fractions with compositional parameters

Abstract

We have carried out a detailed investigation of the pour points (PPt) of gas oil (GO) (250-375 °C boiling range) and vacuum gas oil (VGO) (375-500 °C) fractions obtained from Bombay High crude oil. The aim of the study was to obtain an insight into the dependence of the pour point on compositional parameters such as the n-paraffin concentration (PC) and the influence of the length of the n-paraffinic chain (CL). The experimental work consisted of (i) detailed characterization of both narrow 25°C cuts along with the two broad cuts (250-375 and 375-500 °C) and (ii) a study of the effect of progressive addition of n-paraffin concentrates (urea-adductable portions) of the narrow cuts on the cold-flow behavior of the broad cuts from which the urea adductables have been removed. A simple correlation has been put forward that allows the prediction of the pour point from a knowledge of PC and CL. The study should provide a rational basis for a fundamental predictive method for the cold-flow behavior of GO and VGO fractions.