4.  Active metal surface area per gram of sample

Solved examples:

1.  Calculate the metal dispersion and active metal area for 0.5 wt % Platinum on Alumina catalysts by CO pulse chemisorption. The areas of the pulses are given in the table. Additional given data are:

Sample amount: 1gm; Analysis gas: 10%CO/He; Carrier gas: He; Temperature: 25°C; Pulse volume: 0.5cm³; stoichiometry factor of CO on Pt = 1.

Solution:

i.  Calculation of volume of Active Gas Injected From a Syringe 10 %CO /He

ii.  Calculating Volume Chemisorbed:

V_inj =  volume injected= 0.0448 cm³ ; m = mass of the sample = 1 gm

Table 1. Calculation for volume of CO adsorbed on Pt supported on Alumina

From Table A_f = area of last peak = 0.007

Volume of CO adsorbed on Pt supported on alumina = V_ads = 0.1837 cm³/gm