Evolution of Sulfur Compounds and Hydrocarbons Classes in Diesel Fuels during Hydrodesulfurization. Combined Use of Thin-Layer Chromatography and GC−Sulfur-Selective Chemiluminescence Detection

Abstract

A straight run gas oil has been hydrotreated with a commercial CoMo/Al2O3 catalyst, under variable conditions of severity, in order to yield processed products containing a variable amount of residual sulfur. These products have been characterized by simulated distillation, gas chromatography with sulfur-selective detection (GC−SCD), and thin-layer chromatography. The sulfur compounds have been grouped into distinct representative families. The rate constants for the reaction of desulfurization of the considered groups and the apparent rate order with respect to some individual sulfur compounds have been determined. The following hydrocarbon groups have been determined in the hydrotreated products by analytical thin-layer chromatography−densitometry: alkanes, cycloalkanes, total aromatics, and polyaromatic compounds (PACs). The straight run gas oil has been submitted to fractionation by preparative thin-layer chromatography, and the resulting fractions of alkanes, cycloalkanes, and aromatics have been characterized by simulated distillation and GC−SCD. It has been observed that the sulfur compounds concentrate in the aromatic fraction. In the hydrotreated samples, the content of total aromatics decreases as sulfur is eliminated. Heavy cycloalkanes and PACs remain constant, while the alkanes content increases. The combined use of TLC and GC−SCD allows one to obtain useful information on the gas oil composition and its behavior in the HDS process.

Desulfurization of Commercial Liquid Fuels by Selective Adsorption via π-Complexation with Cu(I)−Y Zeolite

“…Peak identification information for sulfur compounds present in gasoline and diesel was gathered after using standards and by retention time comparison with data available in the literature. ,,− For standards, thiophene, BT, and DBT solutions were diluted in sulfur-free n -octane to a known concentration and then injected for retention time determination. The total sulfur concentration during breakthrough adsorption experiments for either gasoline or diesel was calculated by integrating the entire GC chromatogram regions.…”

Desulfurization of Commercial Jet Fuels by Adsorption via π-Complexation with Vapor Phase Ion Exchanged Cu(I)−Y Zeolites

“…More details about the GC analysis can be found elsewhere. 21,33 Peak identification information for sulfur compounds present in the jet fuel was gathered after using standards and by elution time comparison with data available in the literature. 4,[15][16][17] For standards, stock solutions consisting of thiophene, benzothiophene (BT), or dibenzothiophene (DBT) in sulfur-free n-octane were further diluted to a known concentration and then injected for elution time determination.…”

Monometallic Pd and Pt and Bimetallic Pd-Pt/Al2O3-TiO2for the HDS of DBT: Effect of the Pd and Pt Incorporation Method

“…The hydrodesulfurization (HDS) of straight run gasoil (SRGO) is receiving considerable attention due to stringent environmental requirements, such as a lower sulfur content and the elimination of aromatic compounds in diesel fuel [1][2][3][4]. The different sulfur-containing compounds in SRGO include dibenzothiophene (DBT), 4methyl-dibenzothiophene, and 4,6-dimethyl dibenzothiophene (46DMDBT) [5,6].…”