Kinetics of the heterogeneous decomposition of iron pentacarbonyl

Abstract

Go G, H kI.a K,a L L / D = submergence/diameter ratio N o , phase, dimensionless y Z, Z, rr = total pressure, atm. = column diameter, in. or ft. = absorption efficiency = (yly,)/y, = superficial gas mass velocity, lb./hr.-sq.ft. = superficial gas molar velocity, 1b.-moles/hr.-sq.ft. = Henry's law constant, atm./mole fraction = volumetric liquid phase mass transfer coefficient, = volumetric overall mass transfer coefficient based = nongas flow submergence, in. or ft. of liquid = number of overall transfer units based on gas = mole fraction of oxygen in air = observed height of aerated mass, in. or ft. = equivalent height of clear liquid (also L ) , in. or 1b.-moles/hr.-cu,ft.-mole fraction on gas phase, lb. -moles/hr.-cu. f t.-atm.ft.The decomposition of iron pentacarbonyl a t pressures between one and 400 Torr was studied from 120" to 300°C. Up to about 200°C. the rate was primarily limited by surface kinetics of adsorbed carbonyl. Gas phase diffusional resistances were controlling a t higher temperatures. I n the kinetically controlled region the deposition rate was correlated by a Langmuir type of equation. Corrections for diffusion resistances in the kinetic region and kinetic resistances in the diffusion region were found to be appreciable.

Combined Macro/Nanoscale Investigation of the Chemical Vapor Deposition of Fe from Fe(CO)5

“…Then, simulations are performed in the whole temperature range for the better fitting of the pre-exponential factors. The denominator of Equation (3), which is referred as SR4 in Table 2, expresses the inhibition of the deposition process by the adsorption of CO. E a,CO is the adsorption energy of CO which is taken to be 89.9 kJ mol −1 , [10] P CO,sur is the partial pressure of CO at the boundary of the surface and k CO is the pre-exponential factor of this process. The latter is fitted to the experimental data as described before, by starting from the diffusion-limited regime, where inhibition by CO is more likely.…”

In situ sampling uncovers the dynamics of particle genesis and growth in an aerosol tube reactor

“…1. The kinetics for the heterogeneous reaction have been well studied and can be accurately described by a second-order mechanism [5]. As a result, an adequate application of chemical kinetics, heat transfer and mass transport allows practitioners to reliably deposit metal coatings with precise control of thickness and microstructure.…”

Tuning the Microstructure and Thickness of Ceramic Layers with Advanced Coating Technologies Using Zirconia as an Example

“…The microstructure is particularly influenced by the degree of precursor oversaturation within the interface layer and the surface temperature (affecting the surface diffusion of reaction species). [216,217] The material sources, i.e., the precursors, which must ultimately be gaseous during the deposition process, are much more challenging than those used for PVD. Zirconium chloride (ZrCl 4 ) and yttrium chloride (YCl 3 ) are, for example, common inorganic precursors for the CVD of YSZ.…”

“…The microstructure is particularly influenced by the degree of precursor oversaturation within the interface layer and the surface temperature (affecting the surface diffusion of reaction species). [ 216,217 ]…”