Iron pentacarbonyl properties

The present paper focuses on the interactions between iron and titania for samples prepared via the thermal decomposition of iron pentacarbonyl. (The results of ammonia synthesis studies over these samples have been reported elsewhere (4).) Since it has been reported that standard impregnation techniques cannot be used to prepare highly dispersed iron on titania (4), the use of iron carbonyl decomposition provides a potentially important catalyst preparation route. Studies of the decomposition process as a function of temperature are pertinent to the genesis of such Fe/Ti02 catalysts. For example, these studies are necessary to determine the state and dispersion of iron after the various activation or pretreatment steps. Moreover, such studies are required to understand the catalytic and adsorptive properties of these materials after partial decomposition, complete decarbonylation or hydrogen reduction. In short, Mossbauer spectroscopy was used in this study to monitor the state of iron in catalysts prepared by the decomposition of iron carbonyl. Complementary information about the amount of carbon monoxide associated with iron was provided by volumetric measurements. 

We recognized that the isoelectronic hydrides H2Fe(CO)4 and HCo(CO)4 behaved as pseudo-nickel tetracarbonyls (hydride displacement principle). Moreover, manganese pentacarbonyl hydride (VII, 11), on which we later worked in Munich, was similar in many physical properties to iron pentacarbonyl, leading us to postulate a Drawing-in of the hydrogen... 

Alcoholic solutions of sodium or potassium hydroxide easily absorb iron pentacarbonyl the resulting solution has vigorous reducing properties. 

Two approaches for the synthesis of nanostructured M50 type steel (composed of 4.0% Cr, 4.5% Mo, 1.0% V, 0.8% C and balance Fe) powders and their consolidation are reported in this chapter. One approach involved the sonochemical decomposition of organometallic precursors and the other involved the reduction of the metal halides with lithium triethyl borohydride followed by vaccum sublimation of the powders to remove lithium chloride. The as-synthesized powders are amorphous by X-ray diffraction (XRD) but the peaks corresponding to bcc a-Fe are observed in the compacts. The morphology and composition of the powders synthesized by both techniques, as well as the compacts, were examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Hardness, density, particle size and impurity contents were also determined for the compacts. In addition, pure nanosized iron particles obtained by the ultrasound decompositon of iron pentacarbonyl were consolidated and the properties of the latter were studied. 

Magnetite particles are quite intriguing, due to their catalytic and magnetic properties strongly dependent on the chosen synthesis method. Several methods are described in the literature, but in the present manuscript we are going to focus on the most common ones iron salts co-precipitation (Massart, 1981 Martinez-Mera et al, 2007), sol-gel reaction, microemulsion (Woo et al., 2003), reaction in mass without solvent (Ye et al., 2006), polyols process (Feldmann Jungk, 2001), decomposition of iron pentacarbonyl (Shafi et al., 2001), etc. 

Cyclo-octatetraene-iron tricarbonyl (A) was originally isolated from the reaction mixture of cyclo-octatetraene and iron pentacarbonyl. The properties of A are as follows UV, 303 increasing absorption at shorter... 

The FePt particles are commonly synthesized via decomposition of iron pentacarbonyl, Fe(CO)5, and reduction of platinum acetylacetonate, Pt(acac)2, [236] co-reduction of iron salt and Pt(acac)2, [242] or seed-mediated growth where smaller FePt nanoparticles are used as seeds and more FePt is coated over the seeds. The decomposition and reduction or co-reduction methods can jdeld FePt nanoparticles with controlled composition but fail to produce particles larger than 4 nm, while the seed-mediated growth method gives larger FePt particles without accurate control on Fe/Pt ratio at different sizes. As both stmctural and magnetic properties of FePt nanoparticles depend not only on the size, but also on the composition of the particles [243]. 

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