Molybdenum phosphides

In conclusion, phosphate clearly has a positive effect on HDN. Currently, there are two explanations for this (i) the increased stacking of the MoS2 layers, leading to more accessible hydrogenation sites at the top MoS2 layer, and (ii) the formation of nickel and/or molybdenum phosphide at the edges of the MoS2. 

Molybdenum Phosphide, MoP, is formed when molybdenum trioxide is fused -with phosphoric acid and a little chalk, and the grey crystalline metallic mass is extracted first with hydrochloric acid and then with caustic soda. It has density 6-17, and is readily oxidised on heating in air, treating with nitric acid, or fusing with potassium nitrate. 

There are seven known isotopes of molybdenum that occur naturally Mo, " Mo, Mo, Mo, Mo, Mo, and °°Mo. Their natural abundances range from 9.25 percent ( Mo) to 24.13 percent ( Mo). Common compounds of molybdenum include molybdenum disulfide (M0S2), molybdenum trioxide (M0O3), molybdic acid (H2M0O4), molybdenum hexafluoride (MoFg), and molybdenum phosphide (M0P2). 

A. C. Paul and S. T. Oyama. Alumina-supported molybdenum phosphide hydroprocessing catalysts. J. Catal. 218, 2003, 78-87. 

Z. Feng, C. Liang, W. Wu, Z. Wu, A. R. Santen and C. Li. Carbon monoxide adsorption on molybdenum phosphides Fourier transform infrared spectroscopic and density functional theory studies. /. Phys. Chem. B 107, 2003,13698—13702. 

Phosphides. The crystal structure of MogPj has been shown to involve trigonal prisms of molybdenum atoms each enclosing a central phosphorus atom. M0P4 has been prepared by reaction of the elements at 15—65 kbar and shown to be isostructural with CrP, and therefore to involve the metal atom surrounded by six phosphorus atoms in a distorted octahedral manner. ... 

In a similar vein, it was shown that molybdenum amido derivatives of the isolobal terminal phosphide and carbide, " and related chalcogenide atoms,could be obtained. Detailed mechanistic studies of the Mo N(R)Ar 3/N2 system involving X-ray, EXAFS, magnetic, Raman, and isotopicaUy labelled NMR spectroscopy showed that the reaction proceeded through an intermediate involving an end-on bound N2 bridging the molybdenum centres (Scheme... 

Et20 at -78 °C gives [Mo2(PBu2)4]. The molecule (Figure 5) possesses a central M02P2 butterfly and a terminal phosphide on each molybdenum completes a planar M0P3 arrangement about each metal centre.74... 

Methods of Preparation—Alkali Phosphides—Alkaline Earth Phosphides— Copper, Silver and Gold Phosphides—Zino Group Phosphides—Boron and Aluminium Phosphides—Titanium Group Phosphides—Tin and Lead Phosphides—Arsenic, Antimony and Bismuth Phosphides—Chromium, Molybdenum and Tungsten Phosphides—Manganese Phosphides—Iron, Cobalt and Niokel Phosphides—Platinum Phosphides. 

The strong chemical reactivity of phosphorus allows the formation of single and mixed phosphides with several metals (7-10). Phosphides that are relevant to hydrotreating catalyst formulations (Table II) involve bonding of phosphorus with molybdenum (or tungsten), cobalt, and/or nickel. 

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