Temperature-programmed desorption studies of cracking catalysts. Relationship with microporosity and activity

Conference · Fri Sep 01 04:00:00 EDT 1978 · Prepr., Div. Pet. Chem., Am. Chem. Soc.; (United States)

OSTI ID:6175058

Mieville, R L

The catalysts used universally in catalytic cracking today are a composite of zeolites in a matrix of amorphous silica alumina. These matrix--zeolite catalysts are superior in activity, selectivity, and stability to the previously used silica-aluminas, but a convincing explanation for this superiority has not yet been given. Acidity is well known to be important for cracking activity, and much work has been done on the acid nature of catalysts. However, substantial evidence shows that the properties of zeolite catalysts cannot be explained solely in terms of surface acidity. The higher ratio of Bronsted or protonic to Lewis acidity has been suggested as the main factor for the increased activity and selectivity with zeolites, but the relationship between protonic acidity and catalytic activity is complex and not fully understood. These results suggested that a reinvestigation of hydrocarbon adsorption on cracking catalysts might be fruitful. Consequently, such a study using the technique of temperature-programmed desorption was undertaken. It was found that strongly adsorbing sites for hydrocarbons such as micropores are closely associated with cracking activity. The rate at which hydrocarbon is adsorbed can be correlated with the activity providing a certain level of acidity is present.

• Research Organization: Amoco Oil Co., Naperville, IL
• OSTI ID: 6175058
• Report Number(s): CONF-780902-P4
• Conference Information: Journal Name: Prepr., Div. Pet. Chem., Am. Chem. Soc.; (United States) Journal Volume: 23:4
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400* -- Petroleum-- Processing
ADSORPTION
ALKANES
AROMATICS
CATALYSTS
CATALYTIC CRACKING
CATALYTIC EFFECTS
CHEMICAL REACTIONS
CRACKING
DECOMPOSITION
DESORPTION
HYDROCARBONS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
MINERALS
OCTANE
ORGANIC COMPOUNDS
PYROLYSIS
SORPTION
SORPTIVE PROPERTIES
SURFACE PROPERTIES
THERMOCHEMICAL PROCESSES
TOLUENE
ZEOLITES