Iron pentacarbonyl decomposition high temperature

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. 

High-pressure CO conversion (HiPCO) is a new method for the bulk production of SWCNTs under high-pressure, high-temperature flowing CO on catalytic clusters of Fe. Fe catalyst is formed in situ by thermal decomposition of iron pentacarbonyl (i.e., Fe(CO)j) which is delivered intact within a cold CO flow and then rapidly mixed with hot CO in the reaction zone. Upon heating, the FefCO) decomposes into atoms that condense into larger clusters. SWCNTs nucleate and grow on these particles in the gas phase via CO disproportionation CO-i-CO (catalyzed) CO -i-C(SWCNT) [14,15],... 

If the metal in the precursor is zerovalent, such as in carbonyls, thermal decomposition initially leads to formation of the metal, but two-step procedures can be used to produce oxide nanoparticles as well [30]. In a related work, the synthesis of highly crystalline and monodisperse y-Fe Oj nanocrystallites is reported. High-temperature (300°C) aging of iron-oleic acid metal complex, which was prepared by the thermal decomposition of iron pentacarbonyl in the presence of oleic acid at 100°C, was found to generate monodisperse iron nanoparticles [31]. 

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