Dehydrogenation process for production of styrene from ethylbenzene comprising low temperature heat recovery and modification of the ethylbenzene-steam feed therewith

Patent · Tue Dec 09 04:00:00 EST 1986

OSTI ID:6868390

Sardina, H H

This patent describes a process for the production of styrene from the catalytic dehydrogenation of ethylbenzene in a dehydrogenation zone at elevated temperatures in the presence of steam, whereby the dehydrogenation effluent is cooled and then separated into three phases consisting of a gaseous phase comprising hydrocarbons, an aqueous phase comprising steam condensate, and an organic phase comprising crude styrene and unreacted ethylbenzene. The crude styrene is separated from the unreacted ethylbenzene by distillation and the styrene monomer product is recovered. The overhead from the distillation column for separating the crude styrene from the unreacted ethylbenzene is passed into a condenser into indirect heat exchange with a fluid comprising ethylbenzene and water passing through the condenser. The improvement described here comprises operating the ethylbenzene-water side of the condenser at a pressure between about 8 psia and about 25 psia; operating the column under conditions sufficient for its over head to have a pressure in excess of about 100 mm mercury; the fluid comprising water and ethylbenzene and being vaporized during the indirect heat exchange into a gaseous mixture; and the gaseous mixture being passed into the dehydrogenation zone.

• Assignee: Lummus Crest, Inc., Bloomfield, NJ
• Patent Number(s): US 4628136
• OSTI ID: 6868390
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALKYLATED AROMATICS
AQUEOUS SOLUTIONS
AROMATICS
CATALYSIS
CHEMICAL PREPARATION
CHEMICAL REACTIONS
CONDENSATES
CONDENSERS
COOLING
DEHYDROGENATION
DISPERSIONS
DISTILLATION
ENERGY RECOVERY
ENERGY TRANSFER
EVAPORATION
HEAT RECOVERY
HEAT TRANSFER
HYDROCARBONS
HYDROGEN COMPOUNDS
LOW PRESSURE
MEDIUM PRESSURE
MIXTURES
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
RECOVERY
SEPARATION PROCESSES
SOLUTIONS
STEAM CONDENSERS
STYRENE
SYNTHESIS
TEMPERATURE DEPENDENCE
VAPOR CONDENSERS
WATER