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Explore the highly selective oxidation process of benzyl alcohol with Zn-Fe2O4@ZnO core-shell nanostructures, highlighting benefits of heterogeneous catalysis, easy separation, and reusability. Experimental results, discussions, and conclusions included.
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Highly selective oxidation of benzyl alcohol to benzaldehyde catalyzed by Zn-Fe2O4@ZnO core-shell nanostructures Presenter:Prof. Rahmatollah Rahimi Magor student: Mahdi Heidari-Golafzani
Introduction Experimental Results and discussions Conclusion
Introduction Homogeneous catalysis Oxidation Heterogeneous catalysis
Homogeneous catalysis Benefits • Highactivity and high selectivity • Heat transfer and energy supply for reaction Defects • Purification of catalyst is difficult • Recovery of catalyst is difficult
Heterogeneous catalysis Benefits • Easy separation • Reusability
Important of Zn-Fe2O4@ZnO • Heterogeneous • Magnetisablity • Stability • Easy synthesis
Benzaldehyde • Precursor of pharmaceuticals • Precursor of plastic additives • Prepare of aniline dye malachite green • Precursor of certain acridine dyes • Prepare of cinnamaldehyde and styrene
Experimental H2O2 Cat. Alcohol Acetonitrile 80ºC
Catalyst synthesis Ethylene glycol ZnCl2 FeCl3.6H2O vigorous stirring ammonium acetate Foam
Catalyst synthesis 215ºC black precipitation(Zn-Fe2O4) 48 h
Zn-Fe2O4analysis XRD VSM SEM
01-073-1963 311 440 511 400 220 422
Catalyst synthesis DI Water Zn-Fe2O4 zinc acetate NH3 (pH=11) 3 h, 120ºC 24 h 80ºC Zn-Fe2O4@ZnO
Zn-Fe2O4@ZnOanalysis TEM SEM XRD VSM BET
SEM ̴ 150 nm
VSM 76 emu/g 30 emu/g
catalyst Zn-Fe2O4@ZnO photocatalyst
Comparision Table 3. Comparison with other catalysts a Reaction condition:(1mmol) catalyst, 80C, 1.5h, under 1 atm of molecular oxygen. Conversion and selectivity were determined by GC-MASS using an intemal standard. b Percent of conversion determined by GC-Ms. c Percentofselectivity determined by GC-Ms. d Benzhydrol (1 mmol), 70% TBHP (3 mmol), Cat. (10 mol%), temperature (70 ◦C). e Benzyl alcohol (20.0 mmol), Cat. (10 mol%),30 wt% H2O2 (33.0 mmol), temperature (70 ◦C). f Benzyl alcohol(10.0 mmol), Cat. (1mol%), 30 wt% H2O2 (10.0 mmol), temperature (75 ◦C).
Conclusion • High selectivity • Short reaction time • Heterogeneusly • Inviormentaly firendly • Good to excellent yield • Reusability
References [1]. Burange, A. S., Kale, S. R., Zboril, R., Gawande, M. B., & Jayaram, R. V. (2014). Magnetically retrievable MFe 2 O 4 spinel (M= Mn, Co, Cu, Ni, Zn) catalysts for oxidation of benzylic alcohols to carbonyls. RSC Advances, 4(13), 6597-6601. [2]. Yan, K., Wu, X., An, X., & Xie, X. (2013). Facile synthesis and catalytic property of spinel ferrites by a template method. Journal of Alloys and Compounds, 552, 405-408. [3]. Shi, F., Tse, M. K., Pohl, M.-M., Radnik, J., Brückner, A., Zhang, S., et al. (2008). Nano-iron oxide-catalyzed selective oxidations of alcohols and olefins with hydrogen peroxide. Journal of Molecular Catalysis A: Chemical, 292(1), 28-35. [4]. Rahimi, R., Kerdari, H., Rabbani, M., & Shafiee, M. (2011). Synthesis, characterization and adsorbing properties of hollow Zn-Fe 2 O 4 nanospheres on removal of Congo red from aqueous solution. Desalination, 280(1), 412-418. [5]. Rahimi, R., Heidari-Golafzani, M., & Rabbani, M. (2015). Preparation and photocatalytic application of Zn-Fe 2 O 4@ ZnO core-shell nanostructures. Superlattices and Microstructures.