Binary molybdenum sulfides

Chevrel phases are frequently considered to be reduced molybdenum sulfides because of the low molybdenum oxidation state relative to M0S2. These compounds are also stable under HDS conditions. The low oxidation states are maintained and no decomposition or transformation to other sulfides has been detected for most compounds (61). Chevrel phases usually are obtained through solid-state syntheses at high temperatures (1000-1300°C) by direct combination of the elements or by direct insertion of ternary metal into the binary MogSg... 

The fuels are finely powdered metals (2.0-10.0 g) among which titanium, zirconium, manganese, tungsten, molybdenum and antimony are very common. Sometimes, non-metal powders such as boron and silicon (for fast burning delays), binary alloy powders such as ferrosilicon, zirconium-nickel, aluminum-palladium and metal compounds such as antimony sulfide, calcium silicide etc. are also used. 

The promotion of bulk binary sulfide is limited exclusively to the promotion of molybdenum and tungsten by the first-row transition metal. The effect of the structural promotion (creating more of the same sites) is always coupled to the electronic promotion (creating more active sites). One ap-... 

Recently a fairly inexpensive way of high-temperature experimentation has been found to investigate refractory sulfides and related multicomponent systems up to temperatures of nearly 2000 °C using resistance furnaces. These techniques are discussed below and applied to some sulfide systems, in particular of those metals which belong to the VI-B group. The binary systems chromium-sulfur, molybdenum-sulfur, tungsten-sulfur, as well as some other ternary and quaternary systems and their reactions are reviewed and completed within the limits of the new experimental procedure. 

Temperature dependence of the sulfidation rate of binary Ni-30Mo and ternary Ni-30Mo-xAI alloys compared to the sulfidation rates of nickel and molybdenum. 

Collective plot of the temperature dependence of the sulfidation and oxidation rates of binary and ternary aiioys compared to the suifidation rates of new Fe-Mo-Ai and Ni-Mo-Ai alloys and pure molybdenum (solid iines - suifidation dashed iines -oxidation). 

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