Reduction of SO sub x in regenerator off gas of a fluid cracking unit

Patent · Tue Jul 02 04:00:00 EDT 1991

OSTI ID:5867571

Pratt, R E; Self, D E; Demeter, J C

This patent describes a method which comprises: cracking a sulfur-containing charge hydrocarbon stream in contact with a fluidized bed of fluidized cracking catalyst in a cracking zone at cracking conditions including a temperature of 800{degrees} F. - 1300{degrees} F. whereby at least a portion of the sulfur in the charge hydrocarbon stream is deposited with coke on the cracking catalyst to form spent catalyst containing coke on the cracking catalyst to form spent catalyst containing coke and sulfur and a portion of the sulfur in the charge is converted to gaseous products; passing the spent catalyst containing coke and sulfur from the cracking zone to a fluidized bed in a regeneration zone; admitting oxygen-containing gas to the regeneration zone; maintaining the regeneration zone at 1000{degrees} F. - 1500{degrees} F. thereby regenerating the catalyst and forming a gas containing oxides of carbon and sulfur; contacting the gas containing oxides of carbon and sulfur with a metal surface bearing a layer consisting of rare earth oxide, the metal surface being at least partially immersed in the fluidized bed in the regeneration zone, whereby at least a portion of the sulfur dioxide in the gas is converted to sulfur trioxide thereby forming gas containing increased quantities of sulfur trioxide; and maintaining the gas containing increased quantities of sulfur trioxide in the contact with the cracking catalyst in the regeneration zone whereby at least a portion of the sulfur trioxide is adsorbed onto the cracking catalyst thereby forming a regenerated cracking catalyst bearing sulfur and a flue gas containing decreased quantities of sulfur.

• Assignee: Texaco Inc., White Plains, NY (United States)
• Patent Number(s): A; US 5028310
• Application Number: PPN: US 7-433103
• OSTI ID: 5867571
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400 -- Petroleum-- Processing
020800* -- Petroleum-- Waste Management
54 ENVIRONMENTAL SCIENCES
540120 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
AIR POLLUTION CONTROL
CATALYTIC CRACKING
CATALYTIC REFORMING
CHALCOGENIDES
CHEMICAL REACTIONS
CONTROL
CRACKING
DECOMPOSITION
DESULFURIZATION
FLUE GAS
FLUIDIZED BED REACTORS
FUEL DISPERSION REACTORS
GASEOUS WASTES
HOMOGENEOUS REACTORS
HYDROCARBONS
INDUSTRIAL PLANTS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PETROLEUM REFINERIES
POLLUTION CONTROL
PYROLYSIS
REACTORS
REFORMER PROCESSES
SULFUR COMPOUNDS
SULFUR DIOXIDE
SULFUR OXIDES
THERMOCHEMICAL PROCESSES
WASTES