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Author Van Aelst, J.; Philippaerts, A.; Turner, S.; Van Tendeloo, G.; Jacobs, P.; Sels, B. pdf  doi
openurl 
  Title Heterogeneous conjugation of vegetable oil with alkaline treated highly dispersed Ru/USY catalysts Type A1 Journal article
  Year (down) 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 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  
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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. url  doi
openurl 
  Title Towards biolubricant compatible vegetable oils by pore mouth hydrogenation with shape-selective Pt/ZSM-5 catalysts Type A1 Journal article
  Year (down) 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 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  
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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. pdf  url
doi  openurl
  Title Catalyst design by NH4OH treatment of USY zeolite Type A1 Journal article
  Year (down) 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 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  
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Author Philippaerts, A.; Goossens, S.; Vermandel, W.; Tromp, M.; Turner, S.; Geboers, J.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F. pdf  doi
openurl 
  Title Design of Ru-zeolites for hydrogen-free production of conjugated linoleic acid Type A1 Journal article
  Year (down) 2011 Publication Chemsuschem Abbreviated Journal Chemsuschem  
  Volume 4 Issue 6 Pages 757-767  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract While conjugated vegetable oils are currently used as additives in the drying agents of oils and paints, they are also attractive molecules for making bio-plastics. Moreover, conjugated oils will soon be accepted as nutritional additives for functional food products. While current manufacture of conjugated vegetable oils or conjugated linoleic acids (CLAs) uses a homogeneous base as isomerisation catalyst, a heterogeneous alternative is not available today. This contribution presents the direct production of CLAs over Ru supported on different zeolites, varying in topology (ZSM-5, BETA, Y), Si/Al ratio and countercation (H+, Na+, Cs+). Ru/Cs-USY, with a Si/Al ratio of 40, was identified as the most active and selective catalyst for isomerisation of methyl linoleate (cis-9,cis-12 (C18:2)) to CLA at 165 °C. Interestingly, no hydrogen pre-treatment of the catalyst or addition of hydrogen donors is required to achieve industrially relevant isomerisation productivities, namely, 0.7 g of CLA per litre of solvent per minute. Moreover, the biologically most active CLA isomers, namely, cis-9,trans-11, trans-10,cis-12 and trans-9,trans-11, were the main products, especially at low catalyst concentrations. Ex situ physicochemical characterisation with CO chemisorption, extended X-ray absorption fine structure measurements, transmission electron microscopy analysis, and temperature-programmed oxidation reveals the presence of highly dispersed RuO2 species in Ru/Cs-USY(40).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Weinheim Editor  
  Language Wos 000292214000009 Publication Date 2011-04-20  
  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 24 Open Access  
  Notes Fwo Approved Most recent IF: 7.226; 2011 IF: 6.827  
  Call Number UA @ lucian @ c:irua:90352 Serial 660  
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Author Philippaerts, A.; Paulussen, S.; Breesch, A.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Sels, B.; Jacobs, P. pdf  doi
openurl 
  Title Unprecedented shape selectivity in hydrogenation of triacylglycerol molecules with Pt/ZSM-5 zeolite Type A1 Journal article
  Year (down) 2011 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit  
  Volume 50 Issue 17 Pages 3947-3949  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Well tuned: ZSM-5 with platinum nanoparticles preferably hydrogenates trans fatty acids over cis isomers in model triacylglycerols for geometric reasons. The central fatty acid chain reacts faster, pointing to pore mouth adsorption in a tuning fork conformation (see picture). This conformation induces stepwise hydrogenation, resulting in fast removal of the unstable central triene, while formation of saturated chains is limited.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Weinheim Editor  
  Language Wos 000289514100025 Publication Date 2011-03-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1433-7851; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 11.994 Times cited 31 Open Access  
  Notes Approved Most recent IF: 11.994; 2011 IF: 13.455  
  Call Number UA @ lucian @ c:irua:88381 Serial 3814  
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Author Philippaerts, A.; Paulussen, S.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Poelman, H.; Bulut, M.; de Clippel, F.; Smeets, P.; Sels, B.; Jacobs, P. pdf  doi
openurl 
  Title Selectivity in sorption and hydrogenation of methyl oleate and elaidate on MFI zeolites Type A1 Journal article
  Year (down) 2010 Publication Journal of catalysis Abbreviated Journal J Catal  
  Volume 270 Issue 1 Pages 172-184  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Different zeolites were tested for selective removal of methyl elaidate (trans isomer) from an equimolar mixture with methyl oleate (cis isomer). Sorption experiments of the geometric isomers show that only ZSM-5 samples with reduced Al content in the framework are able to discriminate among the bent cis and the linear trans fatty acid methyl esters. Hydrogenation experiments of equimolar methyl oleate and elaidate mixtures at low temperature (65 °C) and high hydrogen pressure (6.0 MPa), using Pt catalysts, confirm this result. Only with a Pt/NaZSM-5 catalyst outspoken selectivity for the hydrogenation of the trans isomer is obtained. In order to prepare a selective Pt/ZSM-5 catalyst, the influence of Pt addition (impregnation, ion-exchange and competitive ion-exchange) and Pt activation (different calcination and reduction temperatures) on the Pt-distribution and Pt particle size was investigated using SEM, bright-field and HR TEM, EDX, electron tomography, CO-chemisorption, XPS, XRD, and UVvis measurements. The best result in terms of hydrogenation activity and selectivity is obtained with a Pt/ZSM-5 catalyst, which is prepared via competitive ion-exchange, followed by slow calcination up to 350 °C under high O2 flow and a reduction up to 500 °C under H2. This preparation method leads to a Pt/ZSM-5 catalyst with the best Pt distribution and the smallest Pt clusters occluded in the zeolite structure. Finally, the influence of zeolite crystal size, morphology, and elemental composition of ZSM-5 on hydrogenation activity and selectivity was investigated in detail.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication San Diego, Calif. Editor  
  Language Wos 000275966100021 Publication Date 2010-01-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-9517; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.844 Times cited 24 Open Access  
  Notes FWO; IAP-IV; Methusalem Approved Most recent IF: 6.844; 2010 IF: 5.415  
  Call Number UA @ lucian @ c:irua:82435 Serial 2970  
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Author Peng, L.; Philippaerts, A.; Ke, X.; van Noyen, J.; de Cleppel, F.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F. doi  openurl
  Title Preparation of sulfonated ordered mesoporous carbon and its use for the esterification of fatty acids Type A1 Journal article
  Year (down) 2010 Publication Catalysis today Abbreviated Journal Catal Today  
  Volume 150 Issue 1/2 Pages 140-146  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Mesoporous carbon, which can be replicated from mesoporous silica and whose surface is hydrophobic, can be an ideal catalyst for the esterification of fatty acids. Here we report an easy and low cost way to prepare sulfonic acid group-functionalized mesoporous carbon. A sample of calcined mesoporous silica SBA-15 was added to an aqueous sucrose solution followed by drying and calcination at different temperatures. In contrast to existing procedures, the obtained hybrid Si/C material was then first sulfonated in H2SO4, before the final removal of the silica template in order to stabilize the porous structure towards the liquid phase sulfonation treatment. Thus the silicacarbon composites, instead of the mesoporous carbon, were successfully sulfonated to introduce SO3H groups, while keeping the ordered mesoporous structure intact. The influence of carbonization temperature was investigated, suggesting an optimum temperature of 873 K. The SO3H group-functionalized mesoporous carbon, denoted as CMK-3-873-SO3H, was characterized by means of XRD, N2 physisorption, SEM, FT-IR, elemental analysis and TEM. It followed that a uniform mesoporous carbon was obtained with an average pore size of 3.89 nm, a specific surface of 807 m2/g and a SO3H group loading of 0.39 meq/g of dry material. Compared with other solid acid catalysts, the resulting material shows enhanced activity in the acid-catalyzed esterification of oleic acid with methanol, and can be used repeatedly. The increased catalytic performance is attributed to the hydrophobic surface and larger pore size of the new catalyst. It can effectively accommodate long chain fatty acids and reject formed water, making the active sites easily accessible.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000275566700024 Publication Date 2009-09-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0920-5861; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.636 Times cited 132 Open Access  
  Notes Approved Most recent IF: 4.636; 2010 IF: 2.993  
  Call Number UA @ lucian @ c:irua:81739 Serial 2706  
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