Quantification of surface acidity on a low surface area material

A method of quantification of surface acidity of a sample, the method comprising the steps of:

• (1) removing surface moisture of the sample using a pretreatment process comprising:
• heating the sample at about 6-10° C./min, from an initial temperature of about 50-100° C. to about 500-600° C., and
• maintaining a temperature of the sample of about 500-600° C. for about 15 to 30 minutes,
• wherein the sample is within a Helium or Argon gas flow at a flow rate of about 20-50 cm3/minute;
• (2) adsorbing a molecular probe on a surface of the sample comprising:
• maintaining a temperature of the sample of about 50-180° C. for about 10 to 20 minutes within a Helium or Argon gas mixed with 5% of the molecular probe flowing at a flow rate of about 10-50 cm3/minute;
• (3) removing physically adsorbed molecular probe from the surface of the sample comprising:
• maintaining a temperature of the sample of about 50-180° C. for about 60 to 120 minutes within a Helium or Argon gas flow at a flow rate of about 25-50 cm3/minute;
• (4) releasing the physically adsorbed molecular probe by a method that includes a temperature programmed desorption (TPD) process comprising:
• heating the sample with the molecular probe adsorption at about 6-10° C./min, from an initial temperature of about 50-100° C. to about 500-900° C., and
• maintaining a temperature of the sample of about 500-900° C. for about 15 to 30 minutes,
• wherein the sample is within a Helium or Argon gas flow at a flow rate of about 20-50 cm3/minute;
• and
• (5) measuring a total amount of the molecular probe physically desorbed from the TPD process by a method that includes mass spectroscopy (MS),
• wherein the sample has a surface area to mass ratio of less than 5 m2/g.