Efficient Co-production of Cyclohexanone and · PDF fileEfficient Co-production of Cyclohexanone and Phenol ... Air Spent Air to Scrubber Oxidation ... Breakthrough catalysis enables

Efficient Co-production of Cyclohexanone and Phenol

Dr. C. Morris Smith

Project Chief Scientist

ExxonMobil Chemical Company

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10th China International Polyamide & Intermediates Forum

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C Morris Smith, Ph.D.ExxonMobil Chemical Company

Efficient Co-production of Cyclohexanoneand Phenol

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Shanghai Technology Center

Baytown Technology Center

European Technology Center

Integrated Global Technology

Baytown, TXClinton, NJ

Brussels

Bangalore

Shanghai

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Focused Strategic Effort

� Advantaged feeds• Feed flexibility

� Lower-cost manufacturing processes• Advanced process and catalysts• Improved energy efficiency and reliability

� Premium products• Higher performance • Higher value

Industry-leading technology creates innovative solu tions

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Advanced Capabilities

Expertise in catalysis and process, products, appli cations and manufacturing

� State-of-the-art capabilities• Fast catalyst discovery• Advanced chemical characterization• Scale-up

� World-class expertise• Catalyst discovery and scale-up• Process development and manufacturing• New products and applications

� Globally leveraged• Application development• Strong customer support

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Hurdles to Cyclohexanone + Phenol Co-production

� First identified by Rhone-Poulenc in 1954, EP # 6B712264

� Significant work in the patent literature by Texaco, Phillips and Phenolchemie over 50+ years did not lead to a commercial process

� Poor selectivity and low yield continued to limit commercial potential

� Cyclohexylbenzene (CHB) yield affected by over-alkylation to heavies and over-hydrogenation to lights

� Poor oxidation selectivity due to 10 secondary H’s that are also subject to oxidation, but don’t yield the desired products

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Alkylation

Zeolite

Oxidation

O2

Cleavage

H2SO4

++

Conventional Hock Process

ExxonMobil Advances Enable New Route

� In 1993, ExxonMobil introduced a new zeolite Cumene process that was rapidly commercialized worldwide

� New process greatly improves CHB selectivity using a new Hydroalkylation catalyst

� Selective oxidation of benzylic H achieved using N-Hydroxyphthalamide (NHPI)

New EM Process Co-produces Cyclohexanone and Phenol at high yields

� Decouples the production of Phenol and Acetone

� All in a process with leading-edge energy efficiency

OH

New Route

Cumene Cumylhydroperoxide

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New EM Process Technology Development

� Research scoping from 2000 to 2005

� Process development began in 2008

� More than 100 patents filed

� Pilot plant demonstrating integrated process

� Integrated process design and model

� Seven reactive steps, multiple separations

� VLE data generation for non-ideal oxygenate species

� Detailed CFD modeling / design of critical mechanical systems

� Scoping for commercial design underway

New EM Process – Baytown, TX Pilot Plant Facility

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New EM Process: Hydroalkylation

� Highly selective production of Cyclohexylbenzene (CHB)

� No Propylene feed

� Cyclohexene generated in-situ and undergoes hydroalkylation over noble metal / zeolite catalyst

� Cyclohexane recovered using selective catalytic dehydrogenation

� Heavies transalkylated to CHB

� Minimal yield loss from unrecoverable alkylation / isomerization products

� Enabled by proprietary catalysts

Hydroalkylation

Dehydrogenation

Transalkylation

2H2 + ++

Cyclohexylbenzene

Yield ~ 97%

Hydroalkylation

Zeolite

Oxidation

O2 NHPI

Cleavage

H2SO4

+OH

2H2 +

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New EM Process: Oxidation

� Thermal oxidation of CHB not selective to desired PCH-HP

� Selectivity improved by NHPI, a chain propagating agent

� NHPI radical (PINO•) abstracts only the benzylic H, accelerating oxidation to desired PCH-HP

� Low levels of secondary hydroperoxides formed; some recoverable to CHB

� Minor yield loss also occurs by PCH-HP decomposition

� High oxidation yield enabled by NHPI under optimized conditions

Hydroalkylation

Zeolite

Oxidation

O2 NHPI

Cleavage

H2SO4

+OH

2H2 +

Oxidation

Hydrogenation Dehydration

+

Phenyl Cyclohexyl Hydroperoxide (PCH-HP)

NHPI

HeavyOxygenates

Yield ~ 94%

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New EM Process: Cleavage

� PCH-HP cleaved to Phenol and Cyclohexanone

� Rates controlled to eliminate Cyclohexanone loss reactions

� 1-Phenylcyclohexene formed but easily recovered

� β-scission can lead to the loss of PCH-HP by forming 6-Hydroxy-hexaphenone (6HHP)

� When optimized, product selectivity is nearly stoichiometric

Hydroalkylation

Zeolite

Oxidation

O2 NHPI

Cleavage

H2SO4

+OH

2H2 +

Cleavage+

O

Phenol

Cyclohexanone

1-phenylcyclohexanol 1-phenylcyclohexene

6-hydroxyhexaphenone (6HHP)

Cyclohexylbenzene

O

HeavyOxygenates

Yield ~ 99%

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Oxygenates SeparationOxygenates Separation

Hydrocarbon LoopHydrocarbon Loop

OxidationLoop

OxidationLoop

New EM Process Flow Diagram

Benzene

Hydrogen

Transalkylation

CyclohexaneDehydrogenation

HydroalkylationBenzene

Purification

HydrocarbonFractionation

HydrogenPurification

Cleavage

Air

Spent Air to Scrubber

Oxidation

Ventto Flare

Hydrogenation

Phenol

Cyclohexanone

Cleavage Product

Fractionation

PhenolPurification

Cyclohexanone Phenol

Fractionation

Overall Product Yield ~ 90%

WO2009131769

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Efficiency, Co-production Drive Advantage

Hydroalkyation

50% Cx-one

50% Phenol

New EM Process Conversion 25%

CHB

SeparationsOxidationCleavage

Benzene

H2 � Co-production of Phenol and Cyclohexanone in one large-scale line

• 45% lower equipment count

� Higher conversion / yield process

• Smaller equipment

• Reduced energy requirements

� Avoids Acetone, no Propylene feed

� Products for highest quality applications

Phenol Conversion 25%

62% Phenol

38% Acetone

C3=

Alkylation SeparationsOxidationCleavage

De-phenolization

AMSHydrogenation

Benzene

Cumene

CyclohexanolDehydration

100% Cx-one

Cyclohexanone Conversion 4%

CyclohexaneRecovery

SeparationsOxidationCleavage

Cyclohexane

Hydrogenation

Benzene

H2

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Summary

� New EM Process produces two high value products in the Benzene derivative chain

� Breakthrough catalysis enables efficient co-production of Cyclohexanone and Phenol eliminating Acetone co-product and Propylene sourcing

� Leading-edge process design leads to substantial reduction in equipment count, increased scale, and improved capital utilization

� Significantly improved energy efficiency supports more sustainable production of petrochemical intermediates

� Commercial-scale facilities scoping is underway

Documents

Efficient Co-production of Cyclohexanone and · PDF fileEfficient Co-production of Cyclohexanone and Phenol ... Air Spent Air to Scrubber Oxidation ... Breakthrough catalysis enables