Desulfurization of model and real fuels by extraction and oxidation processes using an indenylmolybdenum tricarbonyl pre‐catalyst

Abstract

Regulations on the permissible levels of sulfur in transportation fuels are becoming ever more strict, with a global shift towards “zero sulfur” fuels, and the revamp of existing hydrodesulfurization (HDS) facilities to meet these lower caps is cost‐prohibitive. Metal‐catalyzed sulfoxidation chemistry is viewed as an economically viable desulfurization strategy that could complement conventional HDS technology. In the present work, the complex [η5‐IndMo(CO)3Me] (1) (Ind = indenyl) was employed in the catalytic oxidative desulfurization (CODS) of model and real liquid fuels, using aqueous hydrogen peroxide (H2O2) as oxidant. After optimization of the CODS reaction parameters (diesel/H2O2 ratio, catalyst amount, temperature), a high‐sulfur (2000 ppm) model diesel containing benzothiophene, dibenzothiophene, 4‐methyldibenzothiophene and 4,6‐dimethyldibenzothiophene could be completely desulfurized within 2 hr under solvent‐free conditions or in the presence of the ionic liquid 1‐butyl‐3‐methylimidazolium hexafluorophosphate ([BMIM]PF6) as extraction solvent. The catalyst formed under solvent‐free conditions could be recycled without a significant decrease in desulfurization activity. The high performance of the CODS system was verified in the sulfur removal from a commercial untreated diesel fuel with a sulfur content of 2300 ppm, and a jet fuel with a sulfur content of 1100 ppm. Solvent‐free CODS in combination with initial/final extraction gave desulfurization efficiencies of 70% for the diesel fuel and 55% for the jet fuel. CODS with [BMIM]PF6 in combination with initial/final extraction led to a sulfur removal of 95.9% for the diesel fuel, which is one of the best results yet reported for ODS of commercial diesels.

Highly oxidative desulfurization of thiophenic model fuels and real gasoline by Keggin‐type heteropolyanion immobilized on polyaniline and chitosan as an efficient organic–inorganic nanohybrid catalyst

“…Ultra-deep removal of sulfur from gasoline has been a challenging issue and plays a vital economic role in the worldwide petroleum refining industry. 1,2 Significant amounts of sulfur-containing organic compounds, such as mercaptans, dibenzothiophene (DBT), and its derivatives (Th, BT), are undesirable due to their foul odors and impressive corrosive properties. 3 Hereupon, numerous corrective methods for fuel desulfurization have been introduced and adopted in recent years for clean energy generation and environmental protection.…”

Catalytic activity of a new dioxidomolybdenum(vi) complex with a bipodal N2O-donor ligand in sulfur compound oxidation

“…Therefore, industry and academic researchers are searching for new process, such as oxidative desulfurization (ODS), and new catalysts to surpass this problem. [19][20][21] Sulfide oxidation catalyzed by transition metal ions has been explored. The transformation of sulfides to sulfoxides and This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2023 sulfones further aids in the desulphurization goals, and has good applicability to the pharmaceutical and polymer industries, 22 making these products most valuable.…”

“…Therefore, industry and academic researchers are searching for new process, such as oxidative desulfurization (ODS), and new catalysts to surpass this problem. 19–21…”

Membrane-Supported Layered Coordination Polymer as an Advanced Sustainable Catalyst for Desulfurization

“…Among these, catalytic oxidative desulfurization (ODS) is particularly interesting, as it can be employed in tandem with liquid–liquid extraction or adsorption processes, ensuring removal of refractory sulfur compounds from fuels under mild temperatures and atmospheric pressure [ 15 ]. The combination of extraction and catalytic oxidative desulfurization (ECODS) was demonstrated to be a highly efficient method for the production of sulfur-free fuels [ 16 , 17 , 18 , 19 ]. The oxidation of sulfur compounds in ODS processes is usually carried out using hydrogen peroxide as the oxidant, an environmentally benign oxidant with highly active oxygen content (47%) [ 15 ].…”