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Mixed sulfides

Oo, and Sr ferrites mixed sulfides such as Zn—OdS and Pb—OdS and coated particles such as Ee O with Al(OH)2 or Or(OH)2. OontroUed hydrolysis of alkoxides has also been used to produce submicrometer Ti02, doped Ti02, Zr02, doped Zr02, doped Si02, SrTiO, and even cordierite powders (1,3). [Pg.248]

Formation of Sulfides. Thiols react readily with alkenes under the same types of conditions used to manufacture thiols. In this way, dialkyl sulfides and mixed alkyl sulfides can be produced. Sulfides are a principal by-product of thiol production. Mixed sulfides can be formed by the reaction of the thiol using a suitable starting material, as shown in equations 21, 22, and 23. Vinyl sulfides can be produced by the reaction of alkynes with thiols (38). [Pg.12]

Mixed sulfides are prepared in the flavor industry by the reaction of thiols, 2inc oxide, and a bromoalkane (39). Some of these mixed sulfides are constituents of allium, asafetida, coffee, and meat flavors. A representative reaction is represented in equation 24. [Pg.12]

A cationic molybdenum sulfide cluster [Mo3S4(H20)9] " with incomplete cubane-type structure and a cationic nickel-molybdenum mixed sulfide cluster [Mo3NiS4Cl(H20)9p " with complete cubane-type structure were introduced into zeolites NaY, HUSY and KL by ion exchange. Stoichiometry of the ion exchange was well established by elemental analyses. The UV-visible spectra and EXAFS analysis data exhibited that the structure of the molybdenum cluster remained virtually intact after ion exchange. MoNi/NaY catalyst prepared using the molybdenum-nickel sulfide cluster was found to be active and selective for benzothiophene hydrodesulfurization. [Pg.107]

MoSx-CoSx/NaY catalysts, which were prepared by introducing Mo(CO) into CoSx/NaY (l.lCo/SC), showed the identical HDS activities with those of CoSx-MoSx/NaY at the same compositions, as illustrated in Fig.4. Figure-4 suggests that the dispersions of Mo and Co sulfides are not mutually affected by the presence of the other sulfide species or that the formation of catalytically active species, e.g. Co-Mo mixed sulfide species, is independent of the accommodation order. As shown telow, FTIR of NO adsorption, EXAFS, and XPS results supported the latter pwssibility. [Pg.507]

The IR spectra in Fig.7 indicate the preferential adsorption of NO on the Co sites. It may be conjectured that the Mo sulfide species are physically covered by the Co sulfide species or that Co-Mo mixed sulfide species are formed and the chemical natures of the Co and Mo sulfides are mutually modified. The Mo K-edge EXAFS spectra were measured to examine the formation of mixed sulfide species between Co and Mo sulfides. The Fourier transforms are presented in Fig.8 for MoSx/NaY and CoSx-MoSx/NaY. The structural parameters derived from EXAFS analysis are summarized in Table 1. The structure and dispersion of the Mo sulfides in MoSx/NaY are discussed above. With the Co-Mo binary sulfide catalyst, the Mo-Co bondings are clearly observed at 0.283 nm in addition to the Mo-S and Mo-Mo bondings. The Mo-Co distance is close to that reported by Bouwens et al. [7] for a CoMoS phase supported on activated carbon. Detailed analysis of the EXAFS results for CoSx-MoSx/NaY will be presented elsewhere. It is concluded that the Co-Mo mixed sulfides possessing Co-S-Mo chemical bondings are formed in CoSx-MoSx/NaY. [Pg.509]

A mixed sulfide-oxide, P4OgS4, has a structure similar to that of P4O10, except sulfur atoms replace the four oxygen atoms in terminal positions. [Pg.503]

His method of obtaining the metal was as follows. He dissolved the impure zinc oxide in sulfuric acid and passed in hydrogen sulfide. After filtering and washing the precipitate of mixed sulfides, he dissolved it in concentrated hydrochloric acid and evaporated to dryness to drive... [Pg.530]

Cadmium, Zinc, and Lead Sulfides and Their Mixed Sulfides... [Pg.190]

Figure 3.1.3 shows a TEM image of mixed particles of CdS xZnS (jc = 21.5) (upper) and an SEM image of mixes particles of CdSctPbS (jc = 2.1) (lower). In the preparation of the ZnS and PbS seed sols used for the preparation of these mixed sulfide particles, only —4% of the original concentration of Zn2+ and —6% of Pb2+ were used up, repectively. For CdS xZnS prepared in the presence of ZnS seeds,... [Pg.190]

Regarding the chemical nature of species in LB films, XPS has been used to identify mixed sulfide/polysulfides in nonstoichiometric sulfides of copper (9,19), elemental Se in CdAr films exposed to H2Se (75), and the nature of nitrogen-containing species in LB films made from ArH on subphases of amine-complexed metal ions of M2+ [M = Cu (9), Pt, Pd (74)1. The decomposition of PbS in StH acid films has also been investigated by XPS (68,70). Of two XPS studies of HgS formation in FA films (22,45), one was able to demonstrate that the p-HgS form (mefo-cinna-bar) was present. [Pg.255]

Palladium occurs in combination with platinum and is the second most abundant platinum group metal (pgm), accounting for 38% of pgm reserves. The USSR produces over 50% of the world s palladium, which is more than double that produced in South Africa. Two major sources of the metal are braggite, a mixed sulfide of platinum, palladium and nickel, which contains 16-20% palladium, and michenerite (PdBi3). [Pg.1099]

A number of sullidcs have been reported, the best characterized being CojSj. Coi S<. CoS, C01S4. and C0S3. They are prepared either by metal or salt solution reaction w ith S or H S. The mixed sulfides of cohall and mulybdenum have analytic properties of hydrogenation and isomerization. [Pg.411]

The picture here is even less clear than for reduced catalysts. In spite of the fine studies by Delmon and workers on the bulk mixed sulfides, and that of Schuit and De Beer and workers on various hybrid catalysts, it is not conclusively proved that bulk sulfides are the active ingredients for hydrodesulfurization reactions for the mildly sulfided catalysts employed in industry. [Pg.305]

The pH is controlled by addition of base. If sodium carbonate is used, a basic carbonate is precipitated. Caro s acid can also be used to extract nickel preferentially from mixed sulfide ores such as pentlandite (Ni.Fe)9S9.258... [Pg.248]

The disulfides have pyrite (Ru3 and Os), distorted pyrite (Pd) and Cdl2 (Pt) structures all are diamagnetic. There are various mixed sulfides such as Ta2PdS6. [Pg.1004]

In addition, mixed sulfide selenide systems such as P4S2Se are also known, while P Te bonds are found in BaP4Te2. This new material is generated by direct reaction of the elements at 475 °C and consists of P4Tc2 chains made up of six-membered phosphoms rings linked to tellurium atoms (47). The P-Te... [Pg.3711]


See other pages where Mixed sulfides is mentioned: [Pg.42]    [Pg.195]    [Pg.195]    [Pg.548]    [Pg.40]    [Pg.503]    [Pg.510]    [Pg.510]    [Pg.510]    [Pg.511]    [Pg.511]    [Pg.512]    [Pg.493]    [Pg.21]    [Pg.12]    [Pg.458]    [Pg.107]    [Pg.219]    [Pg.221]    [Pg.214]    [Pg.137]    [Pg.300]    [Pg.144]    [Pg.197]    [Pg.338]    [Pg.247]    [Pg.135]    [Pg.171]    [Pg.532]    [Pg.1374]   
See also in sourсe #XX -- [ Pg.458 ]




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