Chemometric approach to assess the diene value in hydrogenated pyrolysis gasoline by voltammetry

Conjugated dienes can affect the distillation and the quality of petroleum products so that methodologies to assay the diene value (DV) are important. In this work, the DV was determined in hydrogenated pyrolysis gasoline samples through a multivariate approach of experimental data obtained from voltammetric measurements and from the official method UOP-326. Forty seven pyrolysis gasoline samples obtained from the petroleum industry in a period of 11 months were split in two sets (calibration and prediction) and assayed by both methods. A partial least square (PLS-1) regression model was built with 117 voltammetric current values obtained from − 2.25 to − 2.95 V (vs. saturated LiCl/ethanol reference electrode) to predict the DV. Using the multivariate method standards of conjugated dienes were not necessary. Two PLS components were adequate for the modeling. The root mean square errors of calibration and prediction were 0.48 and 0.62, respectively. A univariate approach by using styrene and 1,3-pentadiene as diene standards was also investigated.