ASPHALTENES DETERMINATION IN HEAVY PETROLEUM-PRODUCTS BY PARTIAL LEAST-SQUARES ANALYSIS OF UV DATA

The u.v. parameters obtained from the u.v. spectra of several petroleum samples (including crude oils, commercial fuel oils, straight run and visbreaking residues) have been used for the determination of asphaltenes content. Partial least squares (PLS) in latent variables has been used to correlate the u.v. parameters to the IP-143 asphaltenes content. A set of samples (homogeneous on the basis of their u.v. parameters), including the greater part of the commercial fuel oils and visbreaking residues, has been singled out by PLS analysis. For petroleum products belonging to this class, the asphaltenes content can be derived with a maximum error comparable to the precision of the IP-143 precipitation method.