Molybdenum sulfide catalyst

Daage, M., and Chianelli, R. R., Structure-Function Relations in Molybdenum Sulfide Catalysts The Rim-Edge Model. J. Catal., 1994. 149 pp. 414-427. 

Figure 2. These high-resolution micrographs show how a so-called x-ray amorphous, nonstoichiometric molybdenum sulfide catalyst exhibits structural (as well as compositional) heterogeneity. Amorphous, quasi-crystalline, and crystalline regions coexist at the ultramicro level (18,).

Another SIMS study on model systems concerns molybdenum sulfide catalysts. The removal of sulfur from heavy oil fractions is carried out over molybdenum catalysts promoted with cobalt or nickel, in processes called hydrodesulfurization (HDS) [17]. Catalysts are prepared in the oxidic state but have to be sulfided in a mixture of H2S and H2 in order to be active. SIMS sensitively reveals the conversion of Mo03 into MoSi, in model systems of MoCf supported on a thin layer of Si02 [21]. 

Similarly to the case of direct-oxidation anode materials, sulfur-tolerant anode materials based on sulfides [6, 7] or double-perovskite oxides have special requirements for their processing into SOFC layers. For example, nickel sulfide-promoted molybdenum sulfide is tolerant to high sulfur levels [7], However, it has a low melting temperature [6] that has resulted in the development of cobalt sulfide as a stabilizer of the molybdenum sulfide catalyst [6], CoS-MoS2 admixed with Ag has an even higher performance in H2S-containing fuels than in pure H2 [6]. However, processing methods such as PS, infiltration, or sol-gel techniques that can process... 

IR spectra, 27 283, 284 magnetic measurements, 27 280 oxidized state, 27 289 Raman spectra, 27 284 reduced state, 27 291 reflectance spectroscopy, 27 279 X-ray diffraction, 27 272, 273 support interactions, 27 290 Cobalt monoxide, field effect, 27 44, 45 Cobalt(nickel)-molybdenum-sulfide catalysts, 42 417... 

Combustion, 27 189, 190 reaction, sites for, 33 161-166 reaction scheme, 27 190, 196 Commercial isomerization, 6 197 CoMo catalysts, 40 181 See also Cobalt (nickel)-molybdenum-sulfide catalysts Compact-diffuse layer model, 30 224 Compensation behavior, 26 247-315 active surface, 26 253, 254 Arrhenius parameters, see Arrhenius parameters... 

Huang, C.S., K.C. Wang, and J. H.W. Haynes, Hydrogenation of Phenanthrene Over a Commercial Cobalt Molybdenum Sulfide Catalyst Under Severe Reaction Conditions, in Liquid Fuels from Coal, eds., Academic Press, 1977. 

Kushiyama et al (129) reported that phosphorus also promotes the activity of highly divided unsupported molybdenum and cobalt-molybdenum sulfide catalysts for HDS (and HDM) of crude oil, with a maximum at a P/(Co + Mo) atomic ratio of 2. This result warrants attention because it shows that phosphorus may directly modify the active sulfide phase(s) even in the absence of the alumina support. 

Farlow and Signaigo196 describe the preparation of a molybdenum sulfide catalyst from a molybdenum-aluminum alloy ... 

Intrazeolite molybdenum sulfide catalysts (MoSx/NaY) were prepared by a CVD technique using Mo(CO)6. On the basis of the Mo-Mo atomic distance, it has been shown that a MoSs-like molybdenum sulfide dimer clusters are formed when the Si/Al ratio is between 3.5 and 2.4. When the Si/Al ratio was very high, finely dispersed M0S2 particles were formed. The specific activity of molybdenum sulfide clusters for the HDS of thiophene decreased as the Mo-Mo atomic distance increased. It has been substantiated that the morphology, structure, and catalytic activity of intrazeolite molybdenum sulfides are controlled by the host zeolite composition. 

Molybdenum sulfide-based catalysts have been used for hydrodesulfurization (HDS) [6]. The preparation of highly dispersed molybdenum sulfides is one of the ways to increase HDS activity. Zeolite-supported molybdenum sulfide catalysts have received extensive attention because of intrinsically high dispersion of Mo on the high surface area support [4,5]. Furthermore, a combination of highly dispersed metal sulfide and zeolite acidity... 

J.D. Benck, Z. Chen, L.Y. Kuritzky, A.J. Forman, T.F. JaramiUo, Amorphous molybdenum sulfide catalysts for electrochemical hydrogen production insights into the origin of then-catalytic activity (ACS Catalysis, 2012), pp. 1916-1923... 

Farag H et al (2006) Autocatalysis-like behavior of hydrogen sulfide on hydrodesulfurization of polyaromatic thiophenes over a synthesized molybdenum sulfide catalyst Appl Catal Gen 314 114-122... 

Hilsenbeck, S. J. McCarley, R. E. Goldman, A. I. et al. Hydrodesulfurization Activity and EXAFS Characterization of Novel Ternary Tin and Lanthanum Molybdenum Sulfide Catalysts. Chem. Mater. 1998, 10, 125-134. 

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