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Extractive desulfurization (EDS) process of petroleum fuels via effective solvents has been widely investigated in recent decades and has an excellent future as an alternative technique to HDS process. This study was focused on removal of sulfur compounds from heavy Iraqi atmospheric residual oil (IARO) via EDS process without affecting its other properties. Different hydrocarbon solvents (light naphtha, n-heptane and n-hexane), solvent to oil ratios (4/1, 8/1, and 12/1), extraction times (30, 60, and 120 min), and extraction temperatures (30 °C, 60 °C and 90 °C) were investigated on the precipitation of sulfur in Iraqi atmospheric oil residue. The results were showed that increasing of solvent to oil ratio, extraction times, and extraction temperatures enhanced the performance of EDS process. The experimental results proved that 96% of sulfur compounds were eliminated from heavy residual oil using effective n-hexane as solvent under moderate operating conditions as follow: extraction temperature of 90 °C, extraction time of 60 min, and solvent to oil ratio of 12/1. This study prove that extractive desulfurization via hexane-like solvents at the best experimental conditions can achieve satisfactory sulfur removal efficiency of heavy oil via safe, fast, economically and effective process. [ABSTRACT FROM AUTHOR]

The forced oxidation of sulfite ions was conducted to obtain high-quality gypsum in the flue gas desulfurization system. The effects of formic, lactic, acrylic, acetic, propionic, and hexanoic acids added to calcium-based slurry on sulfite oxidation were investigated in this study. Sulfite oxidation was inhibited when the pKa value of organic acids was small or the carbon chain was long. In the identical slurry pH 6, the SO42- fractions of slurries with formic and lactic acids, which have the smallest pKa values, were lower than half that of the additive-free slurry. The addition of hexanoic acid with the longest carbon chain showed a similar SO42- fraction to that of additive-free slurry. These results indicate that the inhibitory effect on sulfite oxidation is more expressed by the acidity of organic acids. The SO42- fraction in the slurry affects the growth and quality of gypsum crystals. The slurry with acetic acid presented the highest SO42- fraction and resulted in the formation of high-quality gypsum crystals. The findings of this study can contribute to the selection of organic acid additives with high desulfurization efficiency and the production of high-quality gypsum. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Photocatalytic aerobic oxidative desulfurization (PAODS) is a sustainable alternative technology to traditional, energy‐intensive fuel desulfurization methods. Nonetheless, its advancement is hindered by the notable challenge of inadequate electron‐hole separation efficiency within the existing catalytic systems. Herein, a Janus 2D/2D heterostructure composed of Co3O4 and CoMoO4 is reported for the PAODS of thiophenic sulfides. Through a combination of detailed experimental characterizations and density functional theory (DFT) calculations, we elucidate the formation of a type II p‐n heterojunction in the catalyst, significantly enhancing electron‐hole separation through electric field force and reducing the possibility of electron‐hole recombination due to the spatial separation of redox centres. The photocatalyst exhibits exceptional activity and demonstrates an impressive performance of 10.4 mmol·g–1·h–1 in the oxidation of dibenzothiophene (DBT). Moreover, the photocatalyst demonstrates profound desulfurization capabilities in real diesel, reinforcing its promising prospects for industrial application. These discoveries provide invaluable insights, both scientifically and practically, towards the development of advanced photocatalysts for PAODS processes. [ABSTRACT FROM AUTHOR]

This study focused on a new approach for valorization of both ground tire rubber (GTR) and nitrate-containing wastewater via simultaneous devulcanization and denitrification. Initially, sulfur-based autotrophic denitrifiers were successfully enriched from three different seed sludge sources, biological nutrient removal (BNR) sludge, anaerobic digester sludge and BNR sludge of a leather organized industrial zone WWTP. Average nitrate removal efficiencies were 96–98%. Biological devulcanization (biodevulcanization) of GTR was later investigated with these enriched cultures. Results revealed that biodevulcanization was only achieved with the culture enriched from BNR sludge of the leather organized industrial zone WWTP, as 3.9% sulfur removal (desulfurization efficiency). Metal sulfate precipitation was speculated to cause an underestimation of the desulfurization ratio. Fourier-transform infrared spectroscopy (FTIR) results demonstrated a decrease in the intensity of the C–S bonds and an increase in intensity of S–O bonds in treated GTR samples. This was attributed to the oxidation of sulfidic crosslinks, i.e. verification of biodevulcanization. This study indicated that simultaneous biodevulcanization and denitrification could be a promising process for valorization of both GTR and nitrate-containing wastewater which in turn would support circular economy and sustainable development. [ABSTRACT FROM AUTHOR]

This study analyzes four distinct crude oil varieties from the Kurdistan Region-Iraq: Taq-Taq (TQ), Sarqala (SA), Khurmala (Kh), and Tawke (TA). Fractionation produced five categories: naphtha, kerosene, light gas oil (LGO), heavy gas oil (HGO), and fuel oil. The research focused on distillation cuts of LGO (241–300°C) and HGO (301–360°C), which contained organic sulfur compounds, contributing to environmental pollution and health hazards during combustion. Oxidative desulfurization (ODS) using hydrogen peroxide and acetic acid at 75°C for 12 hours significantly reduced sulfur content. LGO sulfur content decreased from 0.72% to 0.11% wt in SA and from 2.02% to 0.50% wt in TA, achieving desulfurization efficiencies of 84.72% and 74.25%, respectively. In HGO, sulfur content dropped from 3.67% to 1.78% wt in Kh, with 51.49% efficiency. Gas oil recovery after oxidation ranged from 92.71% to 96.28%. Solvent extraction with acetonitrile, methanol, and acetic acid further enhanced desulfurization, with pre-oxidation extraction achieving 19.42% efficiency in LGO, increasing to 86% post-oxidation. Gas chromatography with a flame photometric detector (PFPD) assessed sulfur removal, highlighting the combined effects of oxidation and extraction on sulfur compound reduction. This approach demonstrated the efficiency of ODS in mitigating sulfur-related impacts. [ABSTRACT FROM AUTHOR]

Ge[N(SiMe3)2]2 reacts with isocyanates but its reactivity with the related heavier congeners has not been explored. Its reaction with tertiary isothiocyanates results in the abstraction of the sulfur atom to yield a germanium(IV) dimer [((SiMe3)2N)2GeS]2 in high yield. The reaction with tert-butylisoselenocyanate produced the related dimer [((SiMe3)2N)2GeSe]2 within 5 minutes as shown using 77Se NMR spectroscopy. [ABSTRACT FROM AUTHOR]

In this study, we developed an indirect method for the synthesis of 2-deoxyglycosides with an exclusive β-configuration using glucosyl and galactosyl bromide donors with 2-thioacetyl (SAc) groups. The 2-SAc glucosyl and galactosyl bromide donors were easily obtained through the treatment of 1-OAc, 2-SAc glucose and galactose with HBr-CH3COOH solution, respectively. The glycosylation of such donors with acceptors under an improved Koenigs–Knorr condition resulted in glycosylation products with an exclusive β-configuration in excellent yields. The synthetic approach of 2-SAc glycosyl donors using glycals as the starting materials was also investigated. Based on these studies, the synthetic method of using 2-deoxyglycosides with an exclusive β-configuration through desulfurization will have more practical applications. [ABSTRACT FROM AUTHOR]