Records |
Author |
Van Aelst, J.; Verboekend, D.; Philippaerts, A.; Nuttens, N.; Kurttepeli, M.; Gobechiya, E.; Haouas, M.; Sree, S.P.; Denayer, J.F.M.; Martens, J.A.; Kirschhock, C.E.A.; Taulelle, F.; Bals, S.; Baron, G.V.; Jacobs, P.A.; Sels, B.F. |
Title |
Catalyst design by NH4OH treatment of USY zeolite |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
25 |
Issue |
25 |
Pages |
7130-7144 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Hierarchical zeolites are a class of superior catalysts which couples the intrinsic zeolitic properties to enhanced accessibility and intracrystalline mass transport to and from the active sites. The design of hierarchical USY (Ultra-Stable Y) catalysts is achieved using a sustainable postsynthetic room temperature treatment with mildly alkaline NH4OH ( 0.02(M)) solutions. Starting from a commercial dealuminated USY zeolite (Si/Al = 47), a hierarchical material is obtained by selective and tuneable creation of interconnected and accessible small mesopores (2- 6 nm). In addition, the treatment immediately yields the NH4+ form without the need for additional ion exchange. After NH4OH modification, the crystal morphology is retained, whereas the microporosity and relative crystallinity are decreased. The gradual formation of dense amorphous phases throughout the crystal without significant framework atom leaching rationalizes the very high material yields (>90%). The superior catalytic performance of the developed hierarchical zeolites is demonstrated in the acid-catalyzed isomerization of alpha-pinene and the metal-catalyzed conjugation of safflower oil. Significant improvements in activity and selectivity are attained, as well as a lowered susceptibility to deactivation. The catalytic performance is intimately related to the introduced mesopores, hence enhanced mass transport capacity, and the retained intrinsic zeolitic properties. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000366503700003 |
Publication Date ![sorted by Publication Date field, ascending order (up)](img/sort_asc.gif) |
2015-10-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
64 |
Open Access |
OpenAccess |
Notes |
; The authors thank Dr. M. Thommes and Dr. K. Cychosz for numerous and helpful discussions on the correct evaluation of the Ar isotherms. I. Cuppens is acknowledged for ICP-AES analyses. Research was funded through a PhD grant to J.V.A. of the Agency for Innovation by Science and Technology in Flanders (IWT). D.V. and A.P. acknowledge F.W.O.-Vlaanderen (Research Foundation Flanders) for a postdoctoral fellowship. N.N. thanks the KU Leuven for financial support (FLOF). E.G., C.K., and J.M. acknowledge the long-term structural funding by the Flemish Government (Methusalem). S.B. acknowledges the European Research Council for funding under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement No. 335078-COLOURATOMS. The authors are grateful for financial support by the Belgian government through Interuniversity Attraction Poles (IAP-PAI). They also thank Oleon NV for supplying safflower oil. ; ecas_Sara |
Approved |
Most recent IF: 12.124; 2015 IF: 11.805 |
Call Number |
UA @ lucian @ c:irua:130214 |
Serial |
4147 |
Permanent link to this record |
|
|
|
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 |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000374790200031 |
Publication Date ![sorted by Publication Date field, ascending order (up)](img/sort_asc.gif) |
2016-03-31 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
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 |
|
|
|
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 |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000384865600021 |
Publication Date ![sorted by Publication Date field, ascending order (up)](img/sort_asc.gif) |
2016-09-03 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
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 |
|
Approved |
Most recent IF: 4.339 |
Call Number |
UA @ lucian @ c:irua:137242 |
Serial |
4383 |
Permanent link to this record |
|
|
|
Author |
Martens, J.A.; Bogaerts, A.; De Kimpe, N.; Jacobs, P.A.; Marin, G.B.; Rabaey, K.; Saeys, M.; Verhelst, S. |
Title |
The Chemical Route to a Carbon Dioxide Neutral World |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Chemsuschem |
Abbreviated Journal |
Chemsuschem |
Volume |
10 |
Issue |
10 |
Pages |
1039-1055 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Excessive CO2 emissions in the atmosphere from anthropogenic activity can be divided into point sources and diffuse sources. The capture of CO2 from flue gases of large industrial installations and its conversion into fuels and chemicals with fast catalytic processes seems technically possible. Some emerging technologies are already being demonstrated on an industrial scale. Others are still being tested on a laboratory or pilot scale. These emerging chemical technologies can be implemented in a time window ranging from 5 to 20 years. The massive amounts of energy needed for capturing processes and the conversion of CO2 should come from low-carbon energy sources, such as tidal, geothermal, and nuclear energy, but also, mainly, from the sun. Synthetic methane gas that can be formed from CO2 and hydrogen gas is an attractive renewable energy carrier with an existing distribution system. Methanol offers advantages as a liquid fuel and is also a building block for the chemical industry. CO2 emissions from diffuse sources is a difficult problem to solve, particularly for CO2 emissions from road, water, and air transport, but steady progress in the development of technology for capturing CO2 from air is being made. It is impossible to ban carbon from the entire energy
supply of mankind with the current technological knowledge, but a transition to a mixed carbon–hydrogen economy can reduce net CO2 emissions and ultimately lead to a CO2-neutral world. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000398182800002 |
Publication Date ![sorted by Publication Date field, ascending order (up)](img/sort_asc.gif) |
2017-02-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1864-5631 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.226 |
Times cited |
75 |
Open Access |
OpenAccess |
Notes |
This paper is written by members of the Royal Flemish Academy of Belgium for Science and the Arts (KVAB) and external experts. KVAB is acknowledged for supporting the writing and publishing of this viewpoint. Valuable suggestions made by colleagues Jan Kretzschmar, Stan Ulens, and Luc Sterckx are highly appreciated. Special thanks go to Mr. Bert Seghers and Mrs. N. Boelens of KVAB for practical assistance. Mr. Tim Lacoere is acknowledged for graphic design and layout of the figures, and Steven Heylen and Elke Verheyen are acknowledged for data collection and editorial assistance. |
Approved |
Most recent IF: 7.226 |
Call Number |
PLASMANT @ plasmant @ c:irua:141916 |
Serial |
4532 |
Permanent link to this record |
|
|
|
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 |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000711122000001 |
Publication Date ![sorted by Publication Date field, ascending order (up)](img/sort_asc.gif) |
2021-10-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
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 |