Preparation of metallophthalocyanine functionalized magnetic silica nanotubes and its application in ultrasound-assisted oxidative desulfurization of benzothiophene
“…Wang et al fulfilled two separate studies [118] , [119] concerning sonocatalytic ODS (followed by extraction with methanol) of benzothiophene in the presence of H 2 O 2 at 60 °C using core–shell nanosphere modified with metallophthalocyanine (tetra-substituted carboxyl iron phthalocyanine, FeC 4 Pc) encapsulated into magnetic mesopore silica nanoparticles and silica nanotube catalyst with magnetite nanoparticles-coated interior surface and FeC 4 Pc-modified inner and outer surface. Higher desulfurization of the former (at the same conditions, desulfurization near 94.5%) compared to the latter (76% desulfurization yield at 30 min and molar ratio of H 2 O 2 /S = 15) can be considerably clarified by the fact that the particle size (60 nm) and the average pore size (2.6 nm) of the nanosphere composite catalyst are smaller than the outer diameter of the nanotube catalyst (200 nm), hence providing larger surface area for adsorption, though the catalyst loading is not specified in the latter.…”
Section: Types Of Catalysts In Uaodsmentioning
confidence: 99%
“… Fig. 4 DPEs in the presence of heterogeneous catalysts (where 1–3, 4, 5–7, 8, 9, [10,14], 11, 12, 13, [15,19], 16, 17, 18, 20, 21 and 22 represent the references [98] , [133] , [134] , [84] , [151] , [145] , [97] , [119] , [118] , [126] , [124] , [123] , [150] , [65] , [78] , [121] , respectively). *49, 43.50 and 35.50 are DPE values calculated for DBT, 4,6-DMDBT and BT, respectively, pertaining to reference [98] .…”
“…Wang et al fulfilled two separate studies [118] , [119] concerning sonocatalytic ODS (followed by extraction with methanol) of benzothiophene in the presence of H 2 O 2 at 60 °C using core–shell nanosphere modified with metallophthalocyanine (tetra-substituted carboxyl iron phthalocyanine, FeC 4 Pc) encapsulated into magnetic mesopore silica nanoparticles and silica nanotube catalyst with magnetite nanoparticles-coated interior surface and FeC 4 Pc-modified inner and outer surface. Higher desulfurization of the former (at the same conditions, desulfurization near 94.5%) compared to the latter (76% desulfurization yield at 30 min and molar ratio of H 2 O 2 /S = 15) can be considerably clarified by the fact that the particle size (60 nm) and the average pore size (2.6 nm) of the nanosphere composite catalyst are smaller than the outer diameter of the nanotube catalyst (200 nm), hence providing larger surface area for adsorption, though the catalyst loading is not specified in the latter.…”
Section: Types Of Catalysts In Uaodsmentioning
confidence: 99%
“… Fig. 4 DPEs in the presence of heterogeneous catalysts (where 1–3, 4, 5–7, 8, 9, [10,14], 11, 12, 13, [15,19], 16, 17, 18, 20, 21 and 22 represent the references [98] , [133] , [134] , [84] , [151] , [145] , [97] , [119] , [118] , [126] , [124] , [123] , [150] , [65] , [78] , [121] , respectively). *49, 43.50 and 35.50 are DPE values calculated for DBT, 4,6-DMDBT and BT, respectively, pertaining to reference [98] .…”
“…As displayed in Figure a, the a-Cr 2 WO 6 itself has almost no catalytic activity; thus, the oxidation reaction of ODS mainly occurs on WO 3 in a-Cr 2 WO 6 /WO 3 nanowires. It is reported by some literature that the hydroxyl radicals (·OH) produced by the reaction of H 2 O 2 and the catalyst are active species in ODS of DBT. , Moreover, H 2 O 2 may produce a superoxide anion radical (·O 2 – ) during self-decomposition . To prove whether the radicals of ·OH and/or ·O 2 – interact with aromatic thiophenes, the excess of isopropanol (IPA) and p -benzoquinone (PBQ) is used as scavengers to trap radicals of ·OH and ·O 2 – in ODS of DBT, respectively …”
The
oxidative desulfurization (ODS) of fuel oils is of great significance
for environmental protection, and the development of efficient ODS
heterogeneous catalysts is highly desired. Herein, we have designed
and synthesized a novel material of amorphous Cr2WO6-modified WO3 (a-Cr2WO6/WO3) nanowires (3–6 nm) with a large specific surface
area of 289.5 m2·g–1 and rich Lewis
acid sites. The formation of such a unique nanowire is attributed
to the adsorption of Cr3+ cations on non-(001) planes of
WO3. In the ODS process, the a-Cr2WO6/WO3 nanowires can efficiently oxidize benzothiophene
(BT), dibenzothiophene (DBT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT)
to their corresponding sulfones in a quasi-microemulsion reaction
system and possess the highest activity (E
a = 55.4 kJ/mol) for DBT: 99.0% of 15,000 ppm DBT with 2600 ppm S
can be removed (70 °C, H2O2 as the oxidant).
The improvement in ODS activity from most of WO3 catalysts
is owing to the sufficient active sites and enhanced adsorption of
DBT on the basis of structural features of a-Cr2WO6/WO3 nanowires. Combined with free radical capture
experiments, a possible ODS mechanism of W(O2) peroxotungstate
route based on surface −OH groups is reasonably proposed. Moreover,
the a-Cr2WO6/WO3 nanowires have good
stability and can be synthesized on a large scale, suggesting its
potential applications as an efficient heterogeneous catalyst.
“…According to our previous work [26], composite nanomaterials with large surface area may provide a potential solution to the above problems. Mesoporous silica nanoparticles (MSNPs) are drawing a lot of attention owing to their uniform pore size, large surface area, high accessible pore volume, and ease of chemical modification.…”
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
