Upgrading of Orinoco Belt crude oil and its fractions by an electrochemical system in the presence of protonating agents

A review of electrochemical desulfurization technologies for fossil fuels

“…Limitations in these properties are translated into increased cell overpotentials that equate to an increase in the overall cell potential. Exemplary works that have successfully used this method to desulfurize organic compounds include the works of Ovalles et al [24] and Yen et al [9]. In their investigation, Ovalles et al [24] made an interesting observation where higher metal contaminant removal and lower desulfurization for Hamaca residue (500°C + ) was achieved at a current density of 0.02 A cm .…”

“…Exemplary works that have successfully used this method to desulfurize organic compounds include the works of Ovalles et al [24] and Yen et al [9]. In their investigation, Ovalles et al [24] made an interesting observation where higher metal contaminant removal and lower desulfurization for Hamaca residue (500°C + ) was achieved at a current density of 0.02 A cm . Yen et al [9] desulfurized leached oil shale components by applying a constant current density and found that sulfur content could decrease significantly from 2.41% to 0.22% at a fixed current density of 50 mA cm − 2 .…”

“…For example, Ovalles et al [24] found that, with the addition of methanol, both metal and sulfur removal was more efficient for petroporphyrin, Hamaca crude oil and residue (500°C + ). It was found that for the residue (500°C + ), 28% desulfurization could be achieved in the presence of methanol versus 18% in its absence [24]. In addition, the presence of methanol could facilitate the formation of sulfur compound radicals and then initiating polymerization, benefiting the sulfur removal.…”

“…Tetrabutyl ammonium hexafluorophosphate 12% for dibenzothiophene [19] Reduction at − 2.7 V, Pb electrodes LiClO 4 in THF 28% for Hamaca crude oil [24] Oxidation at 115 V, C electrodes LiCl in ethylene-diamine 62% for coal [27] patented an oil purifying method in which hydrocarbon oil was mixed with an electrolyte and an ionizing organic solvent. The mixture was subjected to a potential ranging from 2 to 120 V, producing a current of at least 1 mA cm − 2 .…”

“…Therefore, precious metal catalysts were not needed. Ovalles et al [24] compared the performance of Pb versus Pt cathodes for desulfurization and demetallization via electroreduction of Hamaca petroporphyrins, and found that both demetallization and desulfurization occurred preferentially on Pb by a factor of more than two. Demetallization and desulfurization on Pb were 38% and 28% respectively, compared to 16% and 13% for Pt, which was mainly due to Pt poisoning.…”