Chemisorption Analysis

 

     Home

     Analytical Services

     Surface Area

     Applications

     Full list of Services

     Contact

MCA Services offers dedicated chemisorption analysis using a Micromeritics ASAP 2020 chemisorption instrument

Chemisorption is particularly suited to the analysis of catalytic materials. Common adsorptives are CO (carbon monoxide) and H2 (hydrogen). Typical information that can be determined is listed below and is obtained using the plot shown;

o        Metal Dispersion (%)

o        Metallic Surface Area of Sample (m2g)

o        Metallic Surface Area of Metal (m2g)

o        Crystallite Size (nm)

o        Langmuir Surface Area of Sample (m2g)
                                       o        Freundlich isotherm plot
                                       o        Temkin isotherm plot

CO chemisorption isotherm plot

Example of CO Chemisorption Isotherm Plot

Chemisorption analysis can be further extended to show the difference between strong and weak chemisorption.

An alternative analysis is the measurement of the surface acidity of a material using ammonia adsorption and is particularly applicable to the understanding of zeolite samples. 

Preparation of the sample prior to analysis is undertaken in-situ on the instrument, thereby ensuring the elimination of any contamination. The ASAP 2020 offers a high degree of control over temperature and temperature ramp rate. Temperatures of up to 1100 °C can be reached and vacuum levels of 10-7 mmHg achieved.