Control of refining processes on mid-distillates by near infrared spectroscopy

The purpose of this paper is to demonstrate the accuracy of physicochemical determinations based on equations calculated by multivariate analysis of n ear infrared spectra which gives access to simultaneous analyses both on-li ne and off-line. Detailed results concerning the determination of the refra ctive index at 20 degrees C, the density, the weight% of hydrogen, the % of aromatic cal;bott, the weight% of mono-, di- and total aromatics and the c etane number on mid-distillates are given in a shorter time than using the conventional approach by standardized methods. It is shown that near infrar ed spectroscopy combined with chemometrics should allow detailed and precis e comparisons of the hydrotreatment process efficiencies.