Catalyst For Catalytic Hydrogenation Research Articles

Highly active and stable MoS2-TiO2 nanocomposite catalyst for slurry-phase phenanthrene hydrogenation

MoS2-TiO2 nanocomposite catalysts with Janus structure were synthesized via facile one-step solvothermal method. X-ray diffraction, high resolution transmission electron microscope, NO chemisorption and X-ray photoelectron spectroscopy were applied to characterize the composition and nanostructure of the MoS2-TiO2 nanocomposite catalysts. Experimental results revealed that the MoS2-TiO2 nanocomposite catalysts with Janus structure were composed of MoS2 layers (few stacked layers of 1–3 and short slabs of 2–10 nm) and TiO2 nanoparticles (10–15 nm), which have strong MoS2-TiO2 interaction with transferring electrons from TiO2 to MoS2. Catalytic performance of MoS2-TiO2 nanocomposite catalysts for phenanthrene hydrogenation was investigated and compared with that of MoS2 catalyst in an autoclave reactor with high temperature and high pressure. The phenanthrene conversion over the MoS2-TiO2 nanocomposite catalyst with MoS2 content of 15.0 wt% (MoS2-TiO2-15) can reach 91.6%, which was much higher than 50.4% for MoS2 catalyst and 76.8% for conventional supported MoS2/TiO2-15 catalyst. After 7 cycles of phenanthrene hydrogenation reaction, the phenanthrene conversion over MoS2-TiO2-15 nanocatalyst remained at 68.6%, while the phenanthrene conversion over MoS2 catalyst was reduced to only 25.4%. The MoS2-TiO2 nanocomposite catalysts exhibit significantly enhanced catalytic activity and stability for slurry phase hydrogenation. The enhanced catalytic activity originates from the exposure of abundant coordinatively unsaturated Mo atoms. The enhanced stability results from the Janus structure with stable MoS2-TiO2 interaction and Mo–O–Ti bonds, which anchor MoS2 layers on the surface of TiO2 nanoparticles to avoid the curling, folding and agglomeration of MoS2 layers. This is an important finding on slurry phase catalytic hydrogenation performances of MoS2-based nanocomposite catalysts with Janus structure. Shedding light on the research of Janus nanocomposite catalysts in catalytic hydrogenation is significantly crucial for the development of effective and stable hydrogenation catalysts.

Selective hydrogenation of 2-methylnaphthalene by heterostructured Ni-NiO-based catalysts for 6-methyl-1,2,3,4-tetrahydronaphthalene

As an important intermediate of organic chemical industry, 2-methylnaphthalene (2-MN) has the application value in the field of medicine and material research. Up to date, the existing researches are aimed at 2-methylnaphthalene saturated hydrogenation and hydrocracking for high value products such as cycloalkanes and BTXs. A series of Ni-based (20 wt.%) catalysts were prepared with different reduction temperatures for the hydrogenation of 2-methylnaphthalene to 6-methyl-1,2,3,4-tetrahydronaphthalene (6-MT) in this study. The results showed that by using NiO/Al2O3-370R, 90.8% conversion of 2-MN and 59.7% yield of desired product (6-MT) can be achieved with optimum reaction conditions of 4 MPa & 340°C, 8 h. Multiple studies including catalyst characterizations, reaction kinetics and density functional theory (DFT) calculation indicates that symbiotic effect of heterostructured Ni-NiO over γ-Al2O3 mainly corresponding to the desired catalytic performance. This study gains fundamental understanding in the effects of valence of Ni-based catalysts in catalytic hydrogenation.

Effects of Al and Co Promoters on CuO/SBA-15/Kaolinite Catalyst Properties and CO2 Hydrogenation at Low Pressure

CuO on mesoporous silica catalyst was prepared with post synthesis impregnation method, and the effects of Al and Co promoters on CuO/SBA-15/kaolinite catalyst properties and CO2 hydrogenation were studied. The mixing technology with kaolinite clay (containing Al2O3) was used to obtain the granules and to enhance the CO2 conversion to methanol as a product. The performance of all catalysts for catalytic hydrogenation of CO2 was evaluated on a fixed-bed tubular micro-activity reactor at 20 bar and 250°C with H2/CO2 molar ratio 3:1. XRD analysis, N2 adsorption-desorption analysis and SEM-EDX analysis indicated that the mesoporous structure of SBA-15 remains after loading with CuO and promoters, and after mixing with kaolinite clay. Results were compared with results obtained with commercial CuO/Al2O3 catalyst, which showed high MeOH selectivity (78%) during CO2 hydrogenation reaction.

Promoting Frustrated Lewis Pairs for Heterogeneous Chemoselective Hydrogenation via the Tailored Pore Environment within Metal–Organic Frameworks

AbstractFrustrated Lewis pairs (FLPs) have recently been advanced as efficient metal‐free catalysts for catalytic hydrogenation, but their performance in chemoselective hydrogenation, particularly in heterogeneous systems, has not yet been achieved. Herein, we demonstrate that, via tailoring the pore environment within metal–organic frameworks (MOFs), FLPs not only can be stabilized but also can develop interesting performance in the chemoselective hydrogenation of α,β‐unsaturated organic compounds, which cannot be achieved with FLPs in a homogeneous system. Using hydrogen gas under moderate pressure, the FLP anchored within a MOF that features open metal sites and hydroxy groups on the pore walls can serve as a highly efficient heterogeneous catalyst to selectively reduce the imine bond in α,β‐unsaturated imine substrates to afford unsaturated amine compounds.

Cluster‐like Co4N embedded into carbon sphere as an efficient, magnetic‐separated catalyst for catalytic hydrogenation

AbstractThe transition metal nitrides are promising catalyst in catalytic fields. The decrease of particle size is favourable to improve the catalytic ability, but its synthesis remains a challenge due to high calcination temperature in the synthesis. Here, we have reported the designed synthesis of cluster‐like Co4N paticles (NPs) uniformly embedded in N‐doped carbon microsphere (Co4N@NC) by controllable nitridation of a spherical Co‐HQ−S composed of Co2+ and 8‐hydroxy quinoline (8‐HQ), and its used as efficient hydrogenation catalyst. The Co4N have less size about 3 nm benefited the confined effect of carbon matrix. The small size is favorable to develop the catalytic ability of Co4N and a protection by carbon can enhance its stability. The test indicated that Co4N/NC can act effective catalysts for the hydrogenation by taking the conversion of 4‐nitrophenol (4‐NP) to 4‐aminophenol (4‐AP) as model. The rate constant of 4‐NP conversion is 1.14 min−1 at 25 °C (5 mg of catalyst), much higher than many non‐noble metal catalyst and even comparable to noble metal catalysts. The Co4N/NC can be easily separated by a external magnet with good reuse performance. Importantly, the catalytic ability can be further enhanced by slight increase of the dose of catalyst, and/or reaction temperature. The combination of magnetic property and good catalytic ability makes the Co4N/NC large promising in catalytic fields.

Density functional Studies of structural, electronic and vibrational properties of palladium oxide

Abstract In the present paper, structural properties, electronic properties, phonon dispersion curve and Raman spectra at different pressure of the tetragonal palladium oxide (PdO) using density functional theory are discussed. The electronic band structure and density of states (DOS) show the poor metallic behavior of the system but through the hybrid potential calculation show 0.71 eV band gap. The phonon dispersion curve and Raman spectra confirm the stability of the structure while Raman peaks are slightly shifted toward higher frequency due to the applied pressure. Phonon calculations indicate that the PdO structure is stable up to 10 GPa and slightly unstable at 15 GPa pressure. There is no change of the crystallinity with applied pressure which is observed from the intensities of Raman active mode. Palladium oxides are mainly used as a catalysts for catalytic hydrogenation in organic synthesis.

Soluble Nickel Nanoparticles for Catalytic Hydrogenation

With the rapid development of materials science, the noble metal nanoparticles (NPs) with tunable size and shape have attracted much attention because the tailored nanoparticles affected the catalytic performance tremendously. Besides the noble metal nanoparticles, the easily available transition metal nanoparticles such as Ni-NPs have also been utilized as catalysts recently for various kinds of reactions. In this review, we presented primarily work towards the preparation approach for Ni nanoparticles with predictable and controllable size, shape, composition, and morphology. Especially, the synthetic routes to the controllable Ni nanoparticles through chemical reduction, thermal decomposition, ultrasonic and microwave irradiation, coupling with using reasonably environment-friendly, low cost alternative solvent systems like ionic liquid or w/o microemulsion were illustrated. The particular attention has been given to the recent research progress in employing Ni nanoparticles as catalysts in catalytic hydrogenation of olefins, α, β-unsaturated aldehydes and derivatives of nitrobenzene, and decisive factors influencing the catalytic activity of Ni nanoparticles were then summarized. Keywords: Nickel nanoparticles, Stabilization, Hydrogenation, Catalysis, Immobilization

Application of supported metallic catalysts in catalytic hydrogenation of arenes

Download options Please wait... Article information DOI https://doi.org/10.1039/C3RA40848E Article type Review Article Submitted 20 Feb 2013 Accepted 29 Apr 2013 First published 30 Apr 2013 Download Citation RSC Adv., 2013,3, 14219-14232 BibTex EndNote MEDLINE ProCite ReferenceManager RefWorks RIS Permissions Request permissions Application of supported metallic catalysts in catalytic hydrogenation of arenes S. Qi, X. Wei, Z. Zong and Y. Wang, RSC Adv., 2013, 3, 14219 DOI: 10.1039/C3RA40848E To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page. If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given. If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page. Read more about how to correctly acknowledge RSC content. Social activity Tweet Share Search articles by author Shi-Chao Qi Xian-Yong Wei Zhi-Min Zong Yin-Kai Wang

Preparation of mesoporous oxides and their support effects on Pt nanoparticle catalysts in catalytic hydrogenation of furfural

Mesoporous SiO2, Al2O3, TiO2, Nb2O5, and Ta2O5 were synthesized through a soft-templating approach by a self-assembled framework of Pluronic P123 and utilized for the preparation of 3-dimensional catalysts as supports. Colloidal Pt nanoparticles with an average diameter of 1.9nm were incorporated into the mesoporous oxides by sonication-induced capillary inclusion. The Pt nanoparticles supported on mesoporous oxides were evaluated in the hydrogenation reaction of furfural (70torr furfural and 700torr H2 with a balance of He) to study the effect of catalyst supports on selectivity. In the temperature ranges of 170–240°C, the major products of this reaction were furan, furfuryl alcohol, and 2-methyl furan through a main reaction pathway of either decarbonylation or carbonyl group hydrogenation. While Pt nanoparticles with the size ranges of 1.5–7.1 exhibited strong structure-dependent selectivity, various supports loaded with only 1.9nm Pt nanoparticles produced dominantly furan as a major product. Compared to the inert silica support, TiO2 and Nb2O5 facilitated an increase in the production of furfuryl alcohol via carbonyl group hydrogenation as a result of a charge transfer interaction between the Pt and the acidic surface of the oxides. The same trend was confirmed on 2-dimensional type catalysts, in which thin films of SiO2, Al2O3, TiO2, Nb2O5, and ZrO2 were prepared as supports. When furfural hydrogenation was conducted (1torr furfural, 100torr H2, and 659torr He) over Pt nanoparticle monolayers deposited on oxide substrates, only TiO2 was shown to increase the production of furfuryl alcohol, while other oxides produced furan.

ChemInform Abstract: Role of Bimetallic Catalysts in Catalytic Hydrogenation and Hydrogenolysis

ChemInformVolume 18, Issue 11 Reviews ChemInform Abstract: Role of Bimetallic Catalysts in Catalytic Hydrogenation and Hydrogenolysis L. GUCZI, L. GUCZI Inst. Isot., Hung. Acad. Sci., H-1525 Budapest, Hung.Search for more papers by this authorZ. SCHAY, Z. SCHAY Inst. Isot., Hung. Acad. Sci., H-1525 Budapest, Hung.Search for more papers by this author L. GUCZI, L. GUCZI Inst. Isot., Hung. Acad. Sci., H-1525 Budapest, Hung.Search for more papers by this authorZ. SCHAY, Z. SCHAY Inst. Isot., Hung. Acad. Sci., H-1525 Budapest, Hung.Search for more papers by this author First published: March 17, 1987 https://doi.org/10.1002/chin.198711365Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume18, Issue11March 17, 1987 RelatedInformation

MIXED METAL CATALYSTS IN CATALYTIC HYDROGENATION

Annals of the New York Academy of SciencesVolume 158, Issue 2 p. 540-559 MIXED METAL CATALYSTS IN CATALYTIC HYDROGENATION G.C. Bond, G.C. Bond Johnson Matthey & Co., Ltd., Exhibition Grounds Wembley, Middlesex, EnglandSearch for more papers by this authorD.E. Webster, D.E. Webster Johnson Matthey & Co., Ltd., Exhibition Grounds Wembley, Middlesex, EnglandSearch for more papers by this author G.C. Bond, G.C. Bond Johnson Matthey & Co., Ltd., Exhibition Grounds Wembley, Middlesex, EnglandSearch for more papers by this authorD.E. Webster, D.E. Webster Johnson Matthey & Co., Ltd., Exhibition Grounds Wembley, Middlesex, EnglandSearch for more papers by this author First published: June 1969 https://doi.org/10.1111/j.1749-6632.1969.tb56207.xCitations: 34AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume158, Issue2Second Conference on Catalytic Hydrogenation and Analogous Pressure ReactionsJune 1969Pages 540-559 RelatedInformation