Cost Effective Solutions for High-Grade Cyclohexane Production Jean-Luc Nocca Axens, IFP Group Technologies
CyHex, Aiche Spring Meeting April 2003
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Axens Fully Integrated Services RSI
Eurecat
July 1, 2001
Procatalyse IFP
Licensing
IFP School
Prosernat
Axens Core Business: Licensing, Catalysts, Services CyHex, Aiche Spring Meeting April 2003
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Cyclohexane (CyHex) Market
Others
Caprolactam
CyHex, Aiche Spring Meeting April 2003
Adipic Acid
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CyHex Capacity: 4.5 MMTA
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90% driven by Nylon 6 or Nylon 66 applications
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2-3% growth per year
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Cyclohexane Production Routes
• •
Separation Benzene Hydrogenation
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Heterogeneous Vapor Phase Catalysis Homogeneous Liquid Phase Catalysis
CyHex, Aiche Spring Meeting April 2003
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Chemical Reactions
Main reaction + 3 H2
• •
Highly exothermic
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Impacts final product quality
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Favored by high T°
Side reactions Isomerization
Ring opening
CyHex, Aiche Spring Meeting April 2003
+
H2
Favored by low T° & high ppH2
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Axens Cyclohexane Process
Benzene
• • • • •
Main Reactor Reactor Main
Fixed Bed Bed Fixed Reactor Reactor
99% Bz conversion • Polishing reactor Homogeneous catalysis • Guard bed Bubble point Low T° Reaction heat produces vapor CyHex and steam
CyHex, Aiche Spring Meeting April 2003
Stabilization CyHex Stabilization
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Function of H2 make-up quality
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Main Reactor Features
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Homogeneous catalysis
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Limited initial catalyst inventory Continuous traces (ppm) of catalyst injection ¤ Constant activity
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Tolerant to feed impurities Simple reactor internals
Bubble point reactor
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Constant reactor temperature Safety (liquid inventory)
CyHex, Aiche Spring Meeting April 2003
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Finishing Reactor
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Polishing reactor
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Fixed bed heterogeneous catalysis Vapor phase, low temperature Completes benzene conversion Probe for main reactor operation
Extremely long catalyst life
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> 10 years
CyHex, Aiche Spring Meeting April 2003
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CyHex - PSA Hydrogen Main Reactor
Finishing reactor
Catalyst
HP Sep.
Benzene
H2
Off Gas
CW Steam
LP Sep. Cyclohexane
BFW
Optional CyHex, Aiche Spring Meeting April 2003
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CyHex - Reformer Hydrogen Main Reactor
Finishing reactor
Off Gas
Catalyst HP Sep.
Benzene
Stabilizer
Hydrogen Steam
CW
BFW
Cyclohexane CyHex, Aiche Spring Meeting April 2003
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CyHex Characteristics Industrial Results
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Cyclohexane product purity, wt % 99.97 - 99.994
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Total impurities, ppm
60-300
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Methylcyclopentane, ppm
20-100
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Benzene, ppm
CyHex, Aiche Spring Meeting April 2003
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Axens CyHex Advantages
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Very high CyHex product quality
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Perfect reactor(s) temperature control Complete benzene conversion (< 5 ppm) Minimum (no) side reactions
Low utility consumption
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Use of reaction heat to produce steam No distillation requirement (if PSA H2)
CyHex, Aiche Spring Meeting April 2003
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Axens CyHex Advantages (Cont’d)
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Safety
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Reaction heat removed at constant temperature 2nd generation catalyst for main reactor ¤ easy to handle, non-pyrophoric liquid catalyst
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Low investment
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No proprietary equipment No fired heater or HP steam heater Carbon steel equipment
CyHex, Aiche Spring Meeting April 2003
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CyHex Capacity Increase
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Reactor residence time is not limiting! Simple increase in homogeneous catalyst addition rate
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Increased heat removal by operating conditions adjustment Over 10 units operating at 110-150% design capacity
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CyHex, Aiche Spring Meeting April 2003
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Axens CyHex - Recent Achievements
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Europe
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Middle East
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MoGas Benzene reduction project Morphylane Extractive Distillation + CyHex combination Existing unit upgrading: >50% capacity increase
Undisclosed: new unit 400+ kTA
CyHex, Aiche Spring Meeting April 2003
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Axens CyHex Process - Conclusions
• • • •
Original & performing Low cost Versatile and flexible Industry benchmark for over 40 years (> 50% of worldwide capacity)
Thank You For Your Attention CyHex, Aiche Spring Meeting April 2003
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