Amorphous TiO2-supported Keggin-type ionic liquid catalyst catalytic oxidation of dibenzothiophene in diesel

Abstract

Supported ionic liquid (IL) catalysts [C n mim] 3 PMo 12 O 40 /Am TiO 2 (amorphous TiO 2) were synthesized through a one-step method for extraction coupled catalytic oxidative desulfurization (ECODS) system. Characterizations such as FTIR, DRS, wide-angle XRD, N 2 adsorption-desorption and XPS were applied to analyze the morphology and Keggin structure of the catalysts. In ECODS with hydrogen peroxide as the oxidant, it was found that ILs with longer alkyl chains in the cationic moiety had a better effect on the removal of dibenzothiophene. The desulfurization could reach 100% under optimal conditions, and GC-MS analysis was employed to detect the oxidized product after the reaction. Factors affecting the desulfurization efficiencies were discussed, and a possible mechanism was proposed. In addition, cyclic experiments were also conducted to investigate the recyclability of the supported catalyst. The catalytic activity of [C 16 mim] 3 PMo 12 O 40 /Am TiO 2 only dropped from 100% to 92.9% after ten cycles, demonstrating the good recycling performance of the catalyst and its potential industrial application.

Sono-oxidative desulfurization of fuels using heterogeneous and homogeneous catalysts: A comprehensive review

“…Photocatalyst under UV [54] or visible light [55] , nano-sized silica particles including mesoporous silica [56] , aluminum oxide particles [57] , transition metal oxides [58] , activated carbons [59] , modified metal–organic frameworks [60] , Ni catalyst also called sponge metal [61] , nanocomposite [62] , graphene oxide [63] , activated carbon (AC)-supported phosphotungstic acid [64] and fly ash-modified fenton catalysts [65] are used. In the case of using heterogeneous catalysts, the catalytic ODS mechanism [66] , [67] , [68] , [69] , [70] is illustrated in Scheme 1 . DBT, which is transferred from the organic phase to the aqueous bulk phase by ultrasound, diffuses to the outer surface of the solid catalyst by passing across the liquid film (boundary layer) around the supported catalyst particle.…”

Oxidative desulfurization of diesel fuel oil using supported Fenton catalysts and assisted with ultrasonic energy

“…Experimental results show similar yields compared to other works that use the heterogeneous catalytic oxidative desulfurization approach under the same experimental conditions: 20 min of reaction time, and room temperature. Most of the references report a sulfur removal between 25% and 40% after 20 min of reaction time at room temperature, using different types of metallic catalyst and organic and ionic liquid solvents (Bhasarkar et al 2015b;Hao et al 2016;Jiang et al 2018;Lü et al 2014a;Margeta et al 2016a;Safa et al 2017;Yang et al 2017;Yu et al 2018b;Zhu et al 2015). In the present work, the low-cost raw materials (coal fly ash and distilled ethanol) in the chemical processes approach were used in order to reduce operating cost.…”

Photocatalytic Penicillin Degradation Performance and the Mechanism of the Fragmented TiO2 Modified by CdS Quantum Dots

“…The photocatalytic technology is one of the common methods to fulfill the chemical oxidation that removes pollutants by adopting redox reactions such as ozone oxidation, the Fenton reaction, and photocatalysis. ,, Since Fujishima and Honda first discovered that TiO 2 can successfully realize the water decomposition under visible light in 1972, the photocatalytic degradation technology has received extensive attention. Compared with other semiconductor photocatalysts, such as ZnO, CdS, CuS, and so forth, TiO 2 can be considered as the rapidly emerging water decomposition catalyst due to its advantages including nontoxicity, chemical stability, high photocatalytic activity, and low cost. , However, owing to a large band gap ( E g = 3.2 eV) and wavelength (387 nm), the current TiO 2 photocatalyst is largely limited by the inefficient utilization of solar energy and the rapid recombination rate of photo-generated electron–hole pairs, which eventually lead to lower photocatalytic degradation efficiency of TiO 2 . Therefore, varieties of strategies have been developed to improve the photocatalytic degradation efficiency of TiO 2 , including metal or nonmetal doping, − noble metal deposition, pigment sensitization, high-energy crystal plane exposure, and semiconductor doping. , Adopting appropriate chemical or physical methods to combine multiple semiconductors is an effective method to greatly improve the photocatalytic activity of TiO 2 .…”

“…Compared with other semiconductor photocatalysts, such as ZnO, 18 CdS, 19 CuS, 20 so forth, TiO 2 17 can be considered as the rapidly emerging water decomposition catalyst due to its advantages including nontoxicity, chemical stability, high photocatalytic activity, and low cost. 21,22 However, owing to a large band gap (E g = 3.2 eV) and wavelength (387 nm), the current TiO 2 photocatalyst is largely limited by the inefficient utilization of solar energy and the rapid recombination rate of photo-generated electron− hole pairs, which eventually lead to lower photocatalytic degradation efficiency of TiO 2 . 23 Therefore, varieties of strategies have been developed to improve the photocatalytic degradation efficiency of TiO 2 , including metal or nonmetal doping, 24−31 noble metal deposition, 32 pigment sensitization, 33 high-energy crystal plane exposure, 34 and semiconductor doping.…”