Microporous titania–silica nanocomposite catalyst-adsorbent for ultra-deep oxidative desulfurization

Bazyari, Amin; Khodadadi, Abbas Ali; Mamaghani, Alireza Haghighat; Beheshtian, Javad; Thompson, Levi T.; Mortazavi, Yadollah

doi:10.1016/j.apcatb.2015.06.011

Cited by 162 publications

(88 citation statements)

References 73 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…[19] This intermediate is produced when an oxidant, such as hydrogen peroxide, reacts with the Lewis acidic sites of the metal oxide and leads to the formation of electrophilic species, essential to promote efficient ODS. [20][21][22][23] Among catalyst supports, hollow carbon nanostructures, such as carbon nanotubes, may offer several potential benefits for ODS catalysts. Al 2 O 3 , TiO 2 , and SiO 2 supports have recently been shown to improve the performance of ODS catalysts, therefore, selection of an appropriate support is key for refining the oxidative removal of sulfur contaminants in fuel.…”

Section: Introductionmentioning

confidence: 99%

“…Al 2 O 3 , TiO 2 , and SiO 2 supports have recently been shown to improve the performance of ODS catalysts, therefore, selection of an appropriate support is key for refining the oxidative removal of sulfur contaminants in fuel. [20][21][22][23] Among catalyst supports, hollow carbon nanostructures, such as carbon nanotubes, may offer several potential benefits for ODS catalysts. [24,25] Hollow graphitized nanofibers (GNFs) with an internal diameter of 60 nm-structural analogues to carbon nanotubes, but possessing nanoscale step-edges on the inside-are particularly attractive as their corrugated interior surfaces promote the formation and enhance the stability of catalytic centers, [26][27][28] while increasing the concentration of reactants around the catalyst, without restricting the transport of reactants to and products from the internal cavity (the critical dimensions of most small molecules are typically at least two orders of magnitude smaller than the internal diameter of GNFs).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Molybdenum Dioxide in Carbon Nanoreactors as a Catalytic Nanosponge for the Efficient Desulfurization of Liquid Fuels

Astle

Rance

Loughlin

et al. 2019

Adv Funct Materials

View full text Add to dashboard Cite

The principle of a "catalytic nanosponge" that combines the catalysis of organosulfur oxidation and sequestration of the products from reaction mixtures is demonstrated. Group VI metal oxide nanoparticles (CrO x , MoO x , WO x ) are embedded within hollow graphitized carbon nanofibers (GNFs), which act as nanoscale reaction vessels for oxidation reactions used in the decontamination of fuel. When immersed in a model liquid alkane fuel contaminated with organosulfur compounds (benzothiophene, dibenzothiophene, dimethyldibenzothiophene), it is found that MoO 2 @GNF nanoreactors, comprising 30 nm molybdenum dioxide nanoparticles grown within the channel of GNFs, show superior abilities toward oxidative desulfurization (ODS), affording over 98% sulfur removal at only 5.9 mol% catalyst loading. The role of the carbon nanoreactor in MoO 2 @GNF is to enhance the activity and stability of catalytic centers over at least 5 cycles. Surprisingly, the nanotube cavity can selectively absorb and remove the ODS products (sulfoxides and sulfones) from several model fuel systems. This effect is related to an adsorptive desulfurization (ADS) mechanism, which in combination with ODS within the same material, yields a "catalytic nanosponge" MoO 2 @GNF. This innovative ODS and ADS synergistic functionality negates the need for a solvent extraction step in fuel desulfurization and produces ultralow sulfur fuel.

show abstract

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

Molybdenum Dioxide in Carbon Nanoreactors as a Catalytic Nanosponge for the Efficient Desulfurization of Liquid Fuels

Astle

Rance

Loughlin

et al. 2019

Adv Funct Materials

View full text Add to dashboard Cite

show abstract

“…On the other hand, sulfur compounds are Benzothiophene (BT), Dibenzothiophene (DBT), 3‐methyl thiophen (3‐MT), Thiophen (T), 2‐methyl thiophene (2‐MT), 4,6‐dimethyl dibenzothiophene (4, 6‐DMDBT), Sulfone dibenzothiophene (DBTO), and 4‐methyl dibenzothiophene (4‐MDBT) . For removal, the most effective methods are oxidative denitrogenation (ODN) and oxidative desulfurization (ODS) by catalysts. Meanwhile, zeolite matrixes are a group of catalysts with a high selectivity and a desirable activity to break down the recently introduced C−N and C−S bonds .…”

Section: Introductionmentioning

confidence: 99%

Morphology‐Controlled Synthesis of CuO, CuO Rod/MWW Composite for Advanced Oxidation of Indole and Benzothiophene

et al. 2019

View full text Add to dashboard Cite

Various morphologies of copper (II) oxide (CuO) such as dandelion, sea anemone, walnut, leaf, dendrite, rod, fiber, feather, and flake were synthesized and characterized by different methods. The oxidation of indole (IND) and benzothiophene (BT) in mild conditions was studied by various morphologies of CuO. Walnut with the lowest surface area 7.928 (m2g−1) and rod with a high surface area 41.237 (m2g−1) had efficiencies of 5.93% and 91.44% for IND and 0.53% and 88.29% for BT at 4 h, respectively. Zeolite MWW was synthesized by microwave and hydrothermal method on which CuO rod was loaded via wet impregnation method. The results indicated that CuO rod/MWW composite considerably outperformed CuO rod. The oxidations of IND and BT by CuO rod/MWW composite for 75 min was 99.99 and 97.67%, respectively. Based on the results across all experiments, the oxidation of the IND was higher than that of BT. CuO rod/MWW composite was shown to be an efficient catalyst for oxidation of nitrogen and sulfur heterocycles.

show abstract

“…[16][17][18][19][20] Therefore, oxidative desulfurization is considered to be one of the most promising processes because of its high efficiency for removing refractory sulfur compounds under mild conditions. Various oxidants, including H 2 O 2 , [21][22][23][24][25] tert-butyl hydroperoxide [17,26] and molecular oxygen, [27,28] are employed in oxidative desulfurization processes. Among these, oxygen should be an ideal candidate as an oxidant but it is hard to explore the available catalysts and its reaction condition is still strict.…”

Section: Introductionmentioning

confidence: 99%

Hexacyanoferrate‐based ionic liquids as Fenton‐like catalysts for deep oxidative desulfurization of fuels

Jiang

Yin

et al. 2016

Applied Organom Chemis

View full text Add to dashboard Cite

Two hexacyanoferrate-based ionic liquids, [C 4 Py] 3 Fe(CN) 6 and [C 16 Py] 3 Fe(CN) 6 , were synthesized and characterized using Fourier transform infrared and mass spectroscopies and CHN analysis. They were employed as Fenton-like catalysts in extraction and catalytic oxidative desulfurization of model oil with dibenzothiophene (DBT), benzothiophene (BT), 4,6-dimethyldibenzothiophene (4,6-DMDBT), 4-methyldibenzothiophene (4-MDBT) and 3-methylbenzothiophene (3-MBT) as substrates. Various polar solvents, such as ionic liquids, water and organic solvents, were applied to choose a suitable extractant. The results showed the removal of DBT reached 97.1% with [C 4 Py] 3 Fe(CN) 6 as a catalyst and 1-n-octyl-3-methylimidazolium hexafluorophosphate ([C 8 mim]PF 6 ) as an extractant under optimal conditions. The activity of sulfur removal followed the order DBT > 3-MBT > BT > 4-MDBT >4,6-DMDBT. The effect of water content on sulfur removal was investigated by adding various concentrations of H 2 O 2 . It was found that excess water had a positive effect on sulfur removal but the catalysts were less sensitive than [FeCl 4 À ]-based catalysts to water. The mechanism was studied using electron spin-resonance spectroscopy and gas chromatography-mass spectrometry. O 2•À may be the active oxygen species in the catalytic oxidative desulfurization process and the oxidation products of various sulfur compounds were the corresponding sulfoxides and sulfones.

show abstract

Microporous titania–silica nanocomposite catalyst-adsorbent for ultra-deep oxidative desulfurization

Cited by 162 publications

References 73 publications

Molybdenum Dioxide in Carbon Nanoreactors as a Catalytic Nanosponge for the Efficient Desulfurization of Liquid Fuels

Molybdenum Dioxide in Carbon Nanoreactors as a Catalytic Nanosponge for the Efficient Desulfurization of Liquid Fuels

Morphology‐Controlled Synthesis of CuO, CuO Rod/MWW Composite for Advanced Oxidation of Indole and Benzothiophene

Hexacyanoferrate‐based ionic liquids as Fenton‐like catalysts for deep oxidative desulfurization of fuels

Contact Info

Product

Resources

About