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About OMICS Group OMICS Group International is an amalgamation of Open Access publications and worldwide international science conferences and events.

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Presentation on theme: "About OMICS Group OMICS Group International is an amalgamation of Open Access publications and worldwide international science conferences and events."— Presentation transcript:

1 About OMICS Group OMICS Group International is an amalgamation of Open Access publications and worldwide international science conferences and events. Established in the year 2007 with the sole aim of making the information on Sciences and technology ‘Open Access’, OMICS Group publishes 400 online open access scholarly journals in all aspects of Science, Engineering, Management and Technology journals. OMICS Group has been instrumental in taking the knowledge on Science & technology to the doorsteps of ordinary men and women. Research Scholars, Students, Libraries, Educational Institutions, Research centers and the industry are main stakeholders that benefitted greatly from this knowledge dissemination. OMICS Group also organizes 300 International conferences annually across the globe, where knowledge transfer takes place through debates, round table discussions, poster presentations, workshops, symposia and exhibitions.Open Access publicationsscholarly journalsInternational conferences

2 About OMICS Group Conferences OMICS Group International is a pioneer and leading science event organizer, which publishes around 400 open access journals and conducts over 300 Medical, Clinical, Engineering, Life Sciences, Pharma scientific conferences all over the globe annually with the support of more than 1000 scientific associations and 30,000 editorial board members and 3.5 million followers to its credit. OMICS Group has organized 500 conferences, workshops and national symposiums across the major cities including San Francisco, Las Vegas, San Antonio, Omaha, Orlando, Raleigh, Santa Clara, Chicago, Philadelphia, Baltimore, United Kingdom, Valencia, Dubai, Beijing, Hyderabad, Bengaluru and Mumbai.

3 17.8.2015 The design and synthesis of silica-based catalytic microreactors Raed Abu-Reziq Institute of Chemistry, Casali Center of Applied Chemistry and The Center for Nanoscience and Nanotechnology The Hebrew University of Jerusalem, Israel Ceramics-2015, Chicago, USA

4 Catalysis Health Food Basic and fine chemicals Environment Energy New Materials Catalysis shapes our world Importance of catalysis: more than 90% of the industrial processes are catalyzed (chemicals, pharmaceutics, materials, polymers, energy, etc.)

5 Catalysis Homogeneous Heterogeneous Organometallic complexes Enzymes Organocatalysts Supported metals Supported organometallic complexes Metal oxides, sulfides (PtO 2, RuO 2 etc.)

6 Homogeneous catalysisHeterogeneous catalysis K. D. Wiese et al, Top Organomet. Chem., 2006, 18, 1. H. W. Bohnen et al, Adv. Catal. 2002, 47, 1. High activity and selectivity Not easily recovered Expensive Decrease of activity and selectivity Easily recovered Economic How to bridge homogeneous and heterogeneous catalysis?!! Catalysis Nanocatalysis??

7 Nanocatalysis; Quasi-homogeneous catalysis; Semi- heterogeneous catalysis W. J. Stark et al, Chem. Eur. J., 2010, 16, 8950. Metal nanoparticles as active catalyst Metal nanoparticles as support Preparation of heterogeneous catalysts in the nanometer length scale

8 Nanocatalysis Size Effects K. An and G. A. Somorjai, ChemCatChem, 2012, 14, 1512.

9 Nanocatalysis Shape Effects S.U. Son et al, Angew. Chem. Int. Ed. 2007, 46, 1152

10 Nanocatalysis: Magnetically separable systems a) V. Polshettiwar et al, Chem. Rev., 2011, 111, 3036. b) S. Shyles et al, Angew. Chem. Int. Ed., 2010, 49, 3428. c) Y. Zhu et al, ChemCatChem, 2010, 2, 365. d) V. Polshettiwar et al, Green Chem., 2010,12, 743.

11 Our current research activity Magnetically separable systems Supports with well-defined nanostructures Nano- and Microreactors Bridginghomogeneousandheterogeneous catalysis catalysis

12 Nano & Microreactors Yolk-shell nanoreactors Y. Yang et al, Angew. Chem. Int. Ed. 2012, 51, 9164.E. V. Shevchenko et al, Adv. Mater. 2008, 20, 4323. Carbon nanotubes as nanoreactors S. A. Miners et al, Chem. Commun., 2013, 49, 5586.

13 m.p. (°C) for NaCl= 803 m.p. (°C) for BMIm[PF 6 ]= -78 Ionic liquid based microreactors P. Wasserscheid, T. Welton in “ Ionic Liquids in Synthesis” 2002. Salts that are liquid at ambient temperatures. Have stable liquid range of over 300 °C. Very low vapour pressure at room temperature. Ionic Liquids

14 Applications of ionic liquids: Solvent and catalysts (synthesis, catalysis, microwave chemistry, nanochemistry, multiphasic reactions and extractions) Biological uses (biomass processing, drug delivery, biocides, personal care, embalming) Engineering (coatings, lubricants, plasticisers, dispersing agents, compatibilisers) Physical chemistry ( refractive index, thermodynamics, binary and ternary systems) Electrochemistry (metal plating, solar panels, fuel cells, electro-optics, ion propulsion) N. V. Plechkova, K. R. Seddon, Chem. Soc. Rev. 2008, 37, 123 The high viscosity of ionic liquids limits its applications in industrial processes Ionic liquid based microreactors

15 BMIm-PF 6 @SiO 2 microcapsules Size distribution TEM image SEM image E. Weiss et al, Chem. Mater., 2014, 26, 4781.

16 Particulated ionic liquids: Converting ionic liquids into solid form BMIm-PF 6 @SiO 2 microcapsules TGA analysis indicates that the microcapsules are composed of 68% ionic liquid

17 Parameters affecting the microcapsules synthesis:1.Type of surfactant 2.Surfactant concentration 3.Ionic liquid: TEOS ratio BMIm-PF 6 @SiO 2 microcapsules

18 Brij 78 Tween 80 Triton X-100 Reax 88AReax 88B 5% Bu-PVP SDS PS- sulfonated Pluronic 123 BMIm-PF 6 @SiO 2 microcapsules

19 Characterizations BMIm-PF 6 @SiO 2 microcapsules

20 Immobilization of palladium nanoparticles BMIm-PF 6 @SiO 2 microcapsules

21 Catalytic applications EntryCatalystSolventConversion (%)Products (%) 1Pd/BMIm-PF 6 @SiO 2 water100cis-4-octene (88), trans-4-octene (10), n-octane (2) 2Pd/BMIm-PF 6 @SiO 2 hexane10cis-4-octene (10) 3Pd/BMIm-PF 6 @SiO 2 xylene100cis-4-octene (84), trans-4-octene (5), n-octane (11) 4Pd/BMIm-PF 6 @SiO 2 diethyl ether100cis-4-octene (85), trans-4-octene (6), n-octane (9) 5Pd/Cdiethyl ether100n-octane (100) 6Pd(OAc) 2 BMIm-PF 6 100cis-4-octene (8), n-octane (92) E. Weiss et al, Chem. Mater., 2014, 26, 4781. Pd/BMIm-PF 6 @SiO 2 microcapsules

22 Stability and Recyclability TEM image SEM image SEM and TEM images of Pd/BMIm-PF 6 @SiO 2 after catalytic applications Recyclability BMIm-PF 6 @SiO 2 microcapsules

23 PEG@SiO 2 microcapsules Surfactants: Oil phase: Toluene Heptane Cyclohexane Unpublished results

24 1 µm 10 µm 1 µm PEG@SiO 2 microcapsules PEG@SiO 2 in toluenePEG@SiO 2 in heptane SEM images SEM image TEM image

25 PEG@SiO 2 microcapsules Characterizations

26 PEG@SiO 2 microcapsules [Pt]/PEG@SiO 2 : Selective hydrosilylation catalyst EntrySolventConversion (%)Selectivity (ratio β:α) 1a1a Toluene0--- 2a2a Heptane3373:27 3a3a Cyclohexane5740:60 4b4b Cyclohexane>9992:8 a the catalyst was prepared in the presence of Agrimer AL22 b the catalyst was prepared in the presence of Span 80 Heterogeneous hydrosilylation: M. Chauhan et al, J. Organomet. Chem. 2002, 645,1.

27 PEG@SiO 2 microcapsules [Pt]/PEG@SiO 2 : Selective hydrosilylation catalyst Unpublished results

28 Chiral ruthenium catalyst@ magnetically separable silica microreactors SEM image TEM image A. Zoabi et al, Eur. J. Inorg. Chem., 2015, 2015

29 Chiral ruthenium catalyst@ magnetically separable silica microreactors 29 Si CP-MAS NMR XRD pattern STEM/EDS analysis Characterizations

30 Chiral ruthenium catalyst@ magnetically separable silica microreactors Characterizations 13 C NMR and 13 C CP-MAS NMR

31 Entry Surfactant Conversion (%)Enantioselectivity (ee %) 1Non0- 2CTAB 100 95 3CTAC10095 4SDS5791 5Bu-PVP8892 6Brij 788993 Chiral ruthenium catalyst@ magnetically separable silica microreactors

32 Postulated mechanism for the transportation of the reactants to the core of catalytic microreactors SurfactantZeta potential (mv) Non-26.4 CTAC+44.4 Bu-PVP-3.2 SDS-41.2

33 Chiral ruthenium catalyst@ magnetically separable silica microreactors

34 EntryCatalystYield Enantiomeric excess (%) 1 Microreactors9086 2 Empty capsule anchored catalyst8N/A 3 Sol-gel anchored catalyst4176 Chiral ruthenium catalyst@ magnetically separable silica microreactors Tethering the catalyst in the homogeneous zone of the microreactors is required for obtaining high reactivity and selectivity Comparison of catalytic activity of the microreactors versus sol-gel entrapped and anchored catalyst in the asymmetric transfer hydrogenation of 4-bromoacetophenone

35 Our current research activity Magnetically separable systems Supports with well-defined nanostructures Nano- and Microreactors Bridginghomogeneousandheterogeneous catalysis catalysis

36 Palladium nanoparticles supported on magnetically recoverable hybrid organic-silica nanoparticles Preparation of Pd (nano) /MNP@IL-SiO 2 catalytic hybrid nanoparticles : Magnetically separable systems S. Omar et al, J. Phys. Chem. C, 2014, 118, 30045

37 Characterizations 200 nm200 nm 100 nm100 nm 20 nm20 nm SEM of MNP@IL-SiO 2 TEM of MNP@IL-SiO 2 TEM of Pd (nano) /MNP@IL-SiO 2 STEM of Pd (nano) /MNP@IL-SiO 2 Pd (nano) /MNP@IL-SiO 2

38 Characterizations TGA XRD 29 Si CP-MAS NMR 13 C CP-MAS NMR

39 Pd (nano) /MNP@IL-SiO 2 Catalytic applications

40 Pd (nano) /MNP@IL-SiO 2 Catalytic applications S. Omar et al, J. Phys. Chem. C, 2014, 118, 30045

41 Suzuki reaction between bromonenzene and phenyl boronic acid Heck reaction between iodobenzene and ethyl acrylate SEM images of recycled catalyst after 4 cycles Pd (nano) /MNP@IL-SiO 2 Recycling of the catalysts

42 Conclusions: Two methods for preparing new materials based on ionic liquids or PEG encapsulated in silica shells were developed The methods enable particulating ionic liquids or PEGs and converting them in powder form. The methods give opportunities to design ionic liquids or PEGs with new properties. The methods enable controlling selectivity and reactivity of catalysts Magnetically separable nanocatalysts were designed and applied successfully in different organic transformations.

43 Group members: 1.Suheir Omar 2.Esti Weiss 3.Suzana Natour 4.Amani Zoabi 5.Charlie Batarseh 6.Ahmad Zarour 7.Sumaya Abu-Ghannam 8.Diana Gertopski 9.Dr. Maneesh Gupta Thank You! Funding support 1.Dr. Gilat Nizri 2.Dr. Saleh Abu-Lafi 3.Dr. Bishnu Dutta 4.Dr. Khalil Hamza 5.Rony Schwarz 6.Yafit Schnell Former group members: Casali Foundation Ministry of Science and Culture of Lower Saxony


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