Records |
Author |
Zhong, R.; Peng, L.; de Clippel, F.; Gommes, C.; Goderis, B.; Ke, X.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F. |
Title |
An eco-friendly soft template synthesis of mesostructured silica-carbon nanocomposites for acid catalysis |
Type |
A1 Journal article |
Year |
2015 |
Publication |
ChemCatChem |
Abbreviated Journal |
Chemcatchem |
Volume |
7 |
Issue |
7 |
Pages |
3047-3058 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The synthesis of ordered mesoporous silica-carbon composites was explored by employing TEOS and sucrose as the silica and carbon precursor respectively, and the triblock copolymer F127 as a structure-directing agent via an evaporation-induced self-assembly (EISA) process. It is demonstrated that the synthesis procedures allow for control of the textural properties and final composition of these silica-carbon nanocomposites via adjustment of the effective SiO2/C weight ratio. Characterization by SAXS, N-2 physisorption, HRTEM, TGA, and C-13 and Si-29 solid-state MAS NMR show a 2D hexagonal mesostructure with uniform large pore size ranging from 5.2 to 7.6nm, comprising of separate carbon phases in a continuous silica phase. Ordered mesoporous silica and non-ordered porous carbon can be obtained by combustion of the pyrolyzed nanocomposites in air or etching with HF solution, respectively. Sulfonic acid groups can be readily introduced to such kind of silica-carbon nanocomposites by a standard sulfonation procedure with concentrated sulfuric acid. Excellent acid-catalytic activities and selectivities for the dimerization of styrene to produce 1,3-diphenyl-1-butene and dimerization of -methylstyrene to unsaturated dimers were demonstrated with the sulfonated materials. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000361189400037 |
Publication Date |
2015-09-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
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ISSN |
1867-3880; 1867-3899 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.803 |
Times cited |
13 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.803; 2015 IF: 4.556 |
Call Number |
UA @ lucian @ c:irua:127836 |
Serial |
4138 |
Permanent link to this record |
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Author |
Van Aelst, J.; Philippaerts, A.; Bartholomeeusen, E.; Fayad, E.; Thibault-Starzyk, F.; Lu, J.; Schryvers, D.; Ooms, R.; Verboekend, D.; Jacobs, P.; Sels, B. |
Title |
Towards biolubricant compatible vegetable oils by pore mouth hydrogenation with shape-selective Pt/ZSM-5 catalysts |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Catalysis science & technology |
Abbreviated Journal |
Catal Sci Technol |
Volume |
6 |
Issue |
6 |
Pages |
2820-2828 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Pt/ZSM-5 catalysts with various crystal sizes were prepared via competitive ion-exchange, followed by a slow activation procedure. Even when using very large ZSM-5 crystals, highly dispersed Pt nano-clusters were contained within the zeolite crystal's voids, as ascertained by 2D pressure-jump IR spectroscopy of adsorbed CO and focussed ion-beam transmission electron microscopy. The shape-selective properties of the Pt/ZSM-5 catalysts were evaluated in the partial hydrogenation of soybean oil. Unique hydrogenation selectivities were observed, as the fatty acids located at the central position of the triacylglycerol (TAG) molecules were preferentially hydrogenated. The resulting oil has therefore high levels of intermediately melting TAGs, which are compatible with biolubricants due to their improved oxidative stability and still appropriate low-temperature fluidity. The TAG distribution in the partially hydrogenated soybean oil samples was independent from the zeolite crystal size, while the hydrogenation activity linearly increases with the crystal's external surface area. This trend was confirmed with a Pt loaded mesoporous ZSM-5 zeolite, obtained via a mild alkaline treatment. These observations imply and confirm a genuine pore mouth catalysis mechanism, in which only one fatty acid chain of the TAG is able to enter the micropores of ZSM-5, where the double bonds are hydrogenated by the crystal encapsulated Pt-clusters. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000374790200031 |
Publication Date |
2016-03-31 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2044-4753 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.773 |
Times cited |
5 |
Open Access |
|
Notes |
The research was funded through a PhD grant to J. V. A. of the Agency for Innovation by Science and Technology in Flanders (IWT). A. P. and D. V. acknowledge the F. W. O.-Vlaanderen (Research Foundation Flanders) for a post-doctoral fellowship. E. B. was kindly funded by an F. W. O.-Vlaanderen project. This work was performed in the framework of an Associated International Laboratory between FWO and CNRS. |
Approved |
Most recent IF: 5.773 |
Call Number |
EMAT @ emat @ c:irua:138981 |
Serial |
4335 |
Permanent link to this record |
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Author |
Van Aelst, J.; Philippaerts, A.; Turner, S.; Van Tendeloo, G.; Jacobs, P.; Sels, B. |
Title |
Heterogeneous conjugation of vegetable oil with alkaline treated highly dispersed Ru/USY catalysts |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Applied catalysis : A : general |
Abbreviated Journal |
Appl Catal A-Gen |
Volume |
526 |
Issue |
526 |
Pages |
172-182 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Heterogeneous metal catalysts enable the direct conjugation of linoleic acid tails in vegetable oil to their conjugated linoleic acid (CIA) isomers. CIA-enriched oils are useful as renewable feedstock for the chemical industry and as nutraceutical. Up to now, a solvent-free process for conjugated oils without significant formation of undesired hydrogenation products was not existing. This work shows the design of Ru/USY catalysts able to directly conjugate highly unsaturated vegetable oils such as safflower oil in absence of solvent and hydrogen. Key is fast molecular transport of the bulky reagent and reactive product triglycerides in the zeolite crystal. A two-step zeolite post-synthetic treatment (with NH4OH and acetate salt) was applied to create the necessary mesoporosity. More open zeolite structures allow for a faster conjugation reaction, while securing a fast removal of the reactive conjugated triglycerides, otherwise rapidly deactivating through fouling and pore blockage by polymers. The best Ru/USY catalyst in this contribution is capable of producing exceptionally high yields of conjugated oils, containing up to almost 30 wt% conjugated fatty acid tails in safflower oil, at an initial production rate of 328 g(CLA) mL(-1) h(-1) per gram metal catalyst. (C) 2016 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000384865600021 |
Publication Date |
2016-09-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0926-860x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.339 |
Times cited |
1 |
Open Access |
|
Notes |
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Approved |
Most recent IF: 4.339 |
Call Number |
UA @ lucian @ c:irua:137242 |
Serial |
4383 |
Permanent link to this record |
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Author |
Bartholomeeusen, E.; De Cremer, G.; Kennes, K.; Hammond, C.; Hermans, I.; Lu, J.-B.; Schryvers, D.; Jacobs, P.A.; Roeffaers, M.B.J.; Hofkens, J.; Sels, B.F.; Coutino-Gonzalez, E. |
Title |
Optical encoding of luminescent carbon nanodots in confined spaces |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Chemical Communications |
Abbreviated Journal |
Chem Commun |
Volume |
57 |
Issue |
90 |
Pages |
11952-11955 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Stable emissive carbon nanodots were generated in zeolite crystals using near infrared photon irradiation gradually converting the occluded organic template, originally used to synthesize the zeolite crystals, into discrete luminescent species consisting of nano-sized carbogenic fluorophores, as ascertained using Raman microscopy, and steady-state and time-resolved spectroscopic techniques. Photoactivation in a confocal laser fluorescence microscope allows 3D resolved writing of luminescent carbon nanodot patterns inside zeolites providing a cost-effective and non-toxic alternative to previously reported metal-based nanoclusters confined in zeolites, and opens up opportunities in bio-labelling and sensing applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000711122000001 |
Publication Date |
2021-10-26 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1359-7345; 1364-548x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.319 |
Times cited |
|
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 6.319 |
Call Number |
UA @ admin @ c:irua:184147 |
Serial |
6876 |
Permanent link to this record |
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Author |
Schalm, O.; Proost, K.; De Vis, K.; Cagno, S.; Janssens, K.; Mees, F.; Jacobs, P.; Caen, J. |
Title |
Manganese staining of archaeological glass : the characterization of Mn-rich inclusions in leached layers and a hypothesis of its formation |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Archaeometry |
Abbreviated Journal |
Archaeometry |
Volume |
53 |
Issue |
1 |
Pages |
103-122 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
During the study of a large number of archaeological glass fragments, manganese-rich inclusions in leached layers were observed in a limited number of cases. This phenomenon occurs only in black-coloured leached layers. Since the formation mechanism of such manganese-rich inclusions is still unclear, a combination of several analytical techniques was used in order to investigate this phenomenon and, more specifically, to obtain more information on (a) the composition and morphology of the inclusions, (b) the chemical state of Mn and (c) the 3D morphology of the inclusions. A mechanism that might explain the formation of these inclusions is proposed. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000285418100006 |
Publication Date |
2010-07-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-813x; 1475-4754 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.47 |
Times cited |
24 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 1.47; 2011 IF: 1.183 |
Call Number |
UA @ admin @ c:irua:88754 |
Serial |
5704 |
Permanent link to this record |