Standard Test Method for Hydrogen Chemisorption on Supported Platinum Catalysts by Volumetric Vacuum Method

Importancia y uso:

4.1 This test method sets forth a procedure by which duplicate catalyst samples can be compared either on an interlaboratory or intralaboratory basis. It is anticipated that catalyst producers and users will find this test method of value.

4.2 Discrimination of the samples for which this procedure is recommended must be exercised when considering carrier (support) materials that sorb appreciable quantities of hydrogen or could cause an alteration of the state of the catalyst during pretreatment, or both, (that is, sintering or metal occlusion). These materials must be identified by the user and experimented with to determine the most significant conditions of measurement.

4.3 This test method provides a measure of the total hydrogen uptake (volume of hydrogen at STP, cm³/g of catalyst) without specifying the nature of the hydrogen-platinum interaction. Persons interested in using hydrogen uptake data to calculate percent platinum dispersion in a specific catalyst should be aware of carrier (support) interactions, spillover effects, and other phenomena related to the hydrogen uptake capabilities of the catalyst in question.

Subcomité:

D32.01

Volúmen:

05.06

Número ICS:

71.040.30 (Chemical reagents)

Palabras clave:

chemisorption; hydrogen chemisorption; platinum catalysts; volumetric method;