group acetic acid presentation

Report
Acetic Acid
By
Hamad Shaabi
Reyan Rutherford
Shaun Lynn
Andrew Pollock
Marketing
Acetic Acid Demand Major Region
South
America
2%
Acetic Acid Supply Major Region
Rest of the
Middle East World
Europe
3%
2%
11%
North
America
22%
Middle East
23%
Europe
14%
Asia
57%
Asia
60%
South America
2%
North America
4%
Region
Demand
Supply
Import
Export
Asia
37
57
-
20
North America
22
4
18
-
South America
2
2
-
-
Europe
11
14
-
3
Middles East
2
23
-
20
Marketing
Global Acetic Acid Derivatives
Others
27%
Acetic Anhydride
8%
Acetate Esters
11%
Vinyl Acetate
Monomer
37%
Terephthalic Acid
17%
Acetic acid Derivatives
Uses
Vinyl Acetate Monomer
Paints, adhesives, coating, textiles, wire
and cable polyethylene compounds
Terephthalic Acid
Bottles, textiles, polyester fibers
Acetate Esters
Paints, coating, inks formulation,
sealants, adhesives in pharmaceutical
applications
Acetic Anhydride
Cellulose acetate fibers, plastics,
pharmaceutical such as aspirin
Others
Chemical reagent
Method
Ethylene via acetaldehyde
Methanol by carbonylation
Butane by liquid-phase oxidation
Cativa Process
Ethylene via acetaldehyde
OFF Gas
CO2 Removal
Steam
stm
stm
[PdCl4]²ˉ
C2H4 + H2O + ½O2
CH3CHO + H2O
CuCl2
CH3CHO + H2O
CH3COOH + H2
Extraction System
water
Acetic Acid
Product
Acetic acid
Extractor
Nitrogen
Acetaldehyde Column
Ethylen
e
Oxygen
Acetaldehyde
Acetic Acid Column
Reactor
106 °C
10 ATM
Acetic Acid
scrubber
BFW
Flash tank
H2O
Estimating plant capital costs
Major Process Step
Special Requirements
Score
Reaction
10 atm (0.3), Temp 160 °C(0.3)
,H.G Stainless steel (0.6)
2.2
Scrubber
High grade s.s. (0.6)
1.6
CO2 Removal
High grade s.s. (0.6)
1.6
Acetic Column
High grade s.s. (0.6)
1.6
Acetaldehyde
Column
High grade s.s. (0.6)
1.6
Acetic Finishing
High grade s.s. (0.6) ,
entrainment (0.3)
1.9
Total process complexity factor
10.5
Methanol Carbonylation
Methanol Carbonylation
Most used process for production of Acetic
acid.
Developed by Henry Dreyfus at British
Celanese, pilot plant opened in 1925.
Uses a metal catalyst, usually Rhodium.
CH3OH + CO  CH3COOH
Methanol Carbonylation
1. CH3OH + HI  CH3I + H2O
2. CH3I + CO + [Metal Catalyst] 
CH3COI
3. CH3COI + H2O  CH3COOH + HI
H2O
CH3OH
HI
HI
CH3I
Reaction carried out at a minimum of
200atm.
CH3COI
H2O
CH3COOH
Methanol Carbonylation
• Methanol and carbon monoxide are the
raw materials.
• Bi-products are separated using
distillation.
Methanol Carbonylation Flow
Diagram
Methanol Carbonylation
Complexity Factor
Major Process Step
Special Requirements
Score
Reaction
200 atm (0.9)
Temp 200 °C(0.3)
High Grade Stainless steel (0.6)
2.8
Scrubber
High Grade Stainless steel (0.6)
1.6
CO2 Removal
High Grade Stainless steel (0.6)
1.6
Acetic Column
High Grade Stainless steel (0.6)
1.6
Acetaldehyde Column
High Grade Stainless steel (0.6)
1.6
Acetic Finishing
Entrainment (0.3)
High Grade Stainless steel (0.6)
1.9
Total process complexity factor
11.1
Cativa Process
Cativa
• Developed in 1996 by BP.
• Uses Iridium catalyst.
• Requires Catalytic Promoter – Ruthenium
• Increase in“active anionic” species Ir(CO2)I3Me]-
Mechanism of Iridium Catalysed
Reaction
Cativa Process
• First step is no longer the rate determining step
• Cativa Process 150x faster than Monosanto
• Rate = [catalyst] x [CO]
[I-]
• Very high yield 95-98% at 99% purity
Cativa Flow diagram
Advantages of the Cativa process
• Iridium is much cheaper than rhodium
• Less iridium is needed because it is so stable that all the
catalyst is recycled in the plant
• The reaction is faster and the quantities of by-products are
much lower, reducing the purification costs. For example
steam is used to heat the distillation columns and there is a
30% saving of steam over the Monsanto process
• Some conversion of CO to CO2 still occurs but at a much lower
rate
• CO utilisation is increased from about 85% to over 94%
• Overall the Cativa process releases about 30% less CO2 per
tonne of product than does the rhodium process
Butane by liquid-phase oxidation
Acetic Acid by Butane Oxidation
• When butane is heated with air in the presence of a metal catalysts acetic acid is
produced.
C4H10 + 2½ O2 → 2 CH3COOH + H2O
• Suitanle metal catalysts are manganese, cobalt and chromium.
• Conditions are run at a combination of temperature and pressure designed to be as hot as
possible while keeping the butane in a liquid phase. Typical conditions are 150°C an 55 atm.
• The reaction produces side products such as ethyl acetate, butanone and formic acid
which are commercially valuable.
• Reaction conditions can be altered to produce either of these as the major product if this
is economically useful.
• Before methanol carbonylation became commercialised in the 1980s, Butane oxidation
was the major source of acetic acid
• Now produces less than 10% of acetic acid supply annually.
Thank you any question ?
References:
 G. James, chemical process and design hand book, USA 2001
 A. John & Encyclopedia of chemical technology
 ullmann’s & encyclopedia of industrial chemistry

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