Refractory sulfur compounds in gas oils

Influence of aluminium impregnation on activated carbon for enhanced desulfurization of DBT at ambient temperature: Role of surface acidity and textural properties

“…The residue contains refractory sulfur in form of thiophenes and its derivatives, especially the alkylated ones, which are difficult to desulfurize [7]. HDS involves operation at elevated pressure (3)(4)(5)(6)(7) and temperature (300-400°C), and consequently poses several problems such as high cost of operation, diminution of length of catalyst cycle, and a greater hydrogen consumption for the hydrogenation of olefinic and aromatic compounds presented in fuels [8,9]. However, refinery operations for sulfur removal can combine sulfur-selective adsorption unit and a conventional HDS unit for ultra-deep desulfurization (UDD) of organic sulfur, from the liquid fuel products [5].…”

Investigation of 4,6-dimethyldibenzothiophene hydrodesulfurization over a highly active bulk MoS2 catalyst

“…On looking for a hydrogenation pathway as a prospective alternative choice to overcome the steric hindrance barrier of these alkylated dibenzothiophene species, it is desirable to obtain as effective a hydrogenation catalyst as possible [7][8][9][10][11]. In a previous study [12], it was observed that the HDS of DBT over a bulk MoS 2 catalyst occurred principally through incorporation of the hydrogenation pathway in which phenylcyclohexane was the predominant product.…”

Complete carbon analysis of sulfur‐containing mixtures using postcolumn reaction and flame ionization detection

“…Efficient quantitative analysis of complex mixtures containing hundreds or even thousands of organic compounds remains a prominent analytical chemistry challenge for the 21st century . Of special interest are organic mixtures rich in heteroatoms, including oxygen, sulfur, and nitrogen, which are more difficult to separate and detect by conventional gas chromatography techniques . Conventional detection of eluting compounds by flame ionization detection (FID) is significantly limited in quantifying chemicals with heteroatoms; for example, some oxygenates such as formaldehyde or formic acid are almost undetectable .…”