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Showing 1 to 18 of 18 for “"Phosphides"”.
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Novel, High Activity Hydroprocessing Catalysts: Iron Group Phosphides
… of iron, cobalt and nickel transition metal phosphides was synthesized by means of temperature-programmed reduction (TPR) of the corresponding phosphates. The same materials, Fe₂P, CoP and Ni₂P, were also prepared on a silica (SiO₂) support. The phase purity of these catalysts was established …
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The Preparation of Transition-Metal Phosphides by Fused Salt Electrodes
Made available in DSpace on 2014-12-05T19:36:52Z (GMT). No. of bitstreams: 1 5801751.pdf: 3393351 bytes, checksum: d600edd9e93767a8689b31c93868cf38 (MD5) Previous issue date: 1958
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Reactivity and Structure of Supported Nickel Phosphides (Ni₂P) in Deep Hydrodesulfurization Catalysis
This dissertation describes preparation and characterization of Ni₂P catalysts and their application in deep hydrodesulfurization (HDS) of a model sulfur compound, 4,6-dimethyldibenzothiophene (4,6-DMDBT), one of the most refractory S-compounds. This topic is of great importance in addressing …
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Catalytic Hydrodeoxygenation of Bio-Oil Model Compounds (Ethanol, 2-Methyltetrahydrofuran) over Supported Transition Metal Phosphides
… upgrading bio-oil. A series of transition metal phosphides was prepared and tested; however, the focus was on Ni2P/SiO2. Characterization techniques such as X-ray diffraction (XRD), temperature-programmed reduction and desorption (TPR and TPD), X-ray photoelectron spectroscopy (XPS), and …
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Mechanistic and spectroscopic methods for identifying reactive intermediate structures and active site properties over metals, metal oxides, and metal phosphides
… such as α,ω-diols from furanic species. Metal phosphides are promising catalysts for C-O bond rupture as they are inexpensive, chemically and thermally stable, and selectively cleave C X bonds (where X=S, N, or O) over C-C bonds. In Chapters 3 and 4, we combine kinetic analysis of reaction …
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New Catalysts for Hydroprocessing: Molybdenum and Tungsten Phosphide
… of hydroprocessing catalysts, transition metal phosphides. Concentration was placed on molybdenum and tungsten monophosphides because of the importance of these elements in standard sulfidic hydrotreating catalysts. Transition metal phosphides exist over a wide range of stoichiometry, and their …
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Hidrogenação de ácido levulínico a gama-valerolactona empregando fosfetos de metais de transição suportados em sílica
The following silica supported phosphides with loading of 30 wt% were prepared, characterized and evaluated for levulinic acid hydrogenation to γ- valerolactone: Ni2P, CoP, MoP, WP and Fe2P. The catalysts were prepared in two steps: phosphate synthesis by incipient wetness followed by calcination, …
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Synthetic Levers Enabling Control Of Phase, Size And Morphology In Transition Metal Phosphide Nanoparticles (fe, Ni)
… strategy to control phase in nanoscale iron phosphides; (2) extension of the developed phase control strategy to the nanoscale nickel phosphide system with simultaneous control on size and morphology and (3) illustration of the enhanced reactivity of nanoscale oxide systems.</p> <p>A …
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Synthesis And Characterization Of Size Controlled Transitionmetal Phosphide Nanoparticles And Their Hydrodesulfurization Catalytic Activity
<p>Transition metal phosphides are promising catalysts for hydrodesulfurization (HDS). The size-dependent catalytic activity of these metal phosphides for hydrodesulfurization (HDS) remains unstudied because the traditional temperature programmed reduction (TPR) method used in catalyst preparation …
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Catalytic Hydrogenation and Hydrodesulfurization of Model Compounds
… bimetallic noble metals, transition metal phosphides and transition metal sulfides have been investigated for 2-methylthiophene (2MT) hydrogenation and ring opening. The major products were tetrahydro-2-methylthiophene (TH2MT), pentenes and pentane, with very little C5-thiols observed. The …
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Methodologies for Metal Functionalization of Phosphorus Based Photopolymer Networks
… favors metal oxides, but metal phosphates and phosphides can also be achieved. Further findings showed that tuning the amount of metal in the polymer precursor has the effect of controlling the amount of metal in the ceramics after pyrolysis. Selected polymer networks were patterned before …
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Development of Main Group Systems for Small Molecules Activation
… (H-), carbanions (R3C-), amides (R2N-) or phosphides (R2P-) are shown to activate H2 reversibly and hydrogenate unsaturated molecules. In addition, the reaction of alkali metal species with CO affords the transient anionic carbene intermediate, which can either undergo CO polymerization or …
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Novel Carbon-supported Transition Metal Phosphide Catalysts for Hydrodeoxygenation of Fast Pyrolysis Oil
… i.e., MoP/AC. Two other transition metal phosphides Nickel and Cobalt were also prepared in the same manner using AC support, and their catalytic activities for HDO of pyrolysis oil were compared. The activities of the three catalysts were found to be in the order of NiP/AC > CoP/AC > …
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Crystal structure prediction for rechargeable battery anodes
… electrochemical cycling. For the potassium phosphides, careful energetic comparisons and uncertainty estimates reveal several previously unknown compositions (KP<sub>7</sub>, K<sub>3</sub>P<sub>7</sub>, K<sub>5</sub>P<sub>4</sub>) that are predicted to be stable, including the high capacity …
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Taming reactive phosphorus intermediates with organic and inorganic carriers
… as potential precursors to new tetrel phosphides. Treatment of (THF)Sn[P₃Nb(ODipp)₃]₂ with pyridine-N-oxide effected the formation of ONb(ODipp)₂(py)₂ and a new tin phosphide, [(THF)SnP₆]x, characterized using a multitude of techniques. Additionally, P₃Nb(ODipp)₂(py)₂, prepared from …
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Ab Initio Prediction of Metal Phosphide Anode Materials for Lithium and Beyond Lithium Batteries
… I investigate two classes of transition metal phosphides (TMPs) as candidates for high capacity Li and Na-ion battery anodes. Herein, I employ a computational approach which combines density-functional theory (DFT) with structure searching methods including $Ab$ $Initio$ Random Structure …
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Study of the ligand effects on the metal-ligand bond in some new organometallic complexes using FT-Raman and -IR spectroscopy, isotopic substitution and density functional theory techniques
… All di(2-pyridyl) amides and -phosphides which were synthesized by D-4, coordinate the R2Al+ fragment via both ring nitrogen atoms. This already suggests that the charge density in the anions is coupled into the rings and accumulated at the ring nitrogen atoms, but the Lewis …
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Synthesis And Characterization Of Discrete Fexni2-Xp Nanoparticles; Assembly Of Phosphide Nanoparticles Into Porous Networks
… previously employed for metal chalcogenides, to phosphides is reported for the case of InP and Ni2P. With respect to InP gelation, two different sizes (3.5 and 6.0 nm) of InP nanoparticles were synthesized by solution-phase arrested precipitation, capped with thiolate ligands, and oxidized with …