Determination of the dispersion of active species on catalysts is a tremendous tool to discover and predict the activity of the catalyst. Thus, dispersion of active species indicate the quantity of active particles located on the surface of a catalyst that are accessible and have a direct contact with the reactant molecules that have to react and produce a new substance. Hence, a correct measurement of the dispersion of the active species predict the activity of the catalyst for a specific catalytic process.
The technique comprises the reduction of the active particles in the catalyst at elevated temperature. Usually Hydrogen is widely used for this task and that could be used as pure hydrogen or a mixture of H2 balanced inert gas. Upon completion of reduction and the catalyst temperature is brought back to room temperature, the catalyst is then titrated by using a calibrated loop and dosing known amount of active gas, usually is carbon monoxide or hydrogen. Therefore and upon saturation, the amount of adsorbed active gas is being calculated and related to the accessible active species on the surface of the catalyst. This method of titration is by far, the most useful tool to predict the activity of the catalyst.
Determination of the dispersion of active species on catalysts is a tremendous tool to discover and predict the activity of the catalyst. Thus, dispersion of active species indicate the quantity of active particles located on the surface of a catalyst that are accessible and have a direct contact with the reactant molecules that have to react and produce a new substance. Hence, a correct measurement of the dispersion of the active species predict the activity of the catalyst for a specific catalytic process.
The technique comprises the reduction of the active particles in the catalyst at elevated temperature. Usually Hydrogen is widely used for this task and that could be used as pure hydrogen or a mixture of H2 balanced inert gas. Upon completion of reduction and the catalyst temperature is brought back to room temperature, the catalyst is then titrated by using a calibrated loop and dosing known amount of active gas, usually is carbon monoxide or hydrogen. Therefore and upon saturation, the amount of adsorbed active gas is being calculated and related to the accessible active species on the surface of the catalyst. This method of titration is by far, the most useful tool to predict the activity of the catalyst.
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