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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
INDEX
Chapter Description Page no.
Chapter 1 Abstract 3-4
Chapter 2 Introduction 5 - 7
1.1 Introduction 6
1.2 Applications of methoxyacetone 7
Chapter 2 Literature Survey 8-9
Chapter 3 Properties of Chemicals and Catalyst 10-14
3.1 Properties of methoxy-2 -propanol 11
3.2 Properties of methoxyacetone 12
3.3 Properties of CATALYST copper chromite 13
3.4 Properties of hydrogen 14
Chapter 4 Health & Safety Aspects 15-19
Chapter 5 Methods of Production 20-21
Chapter 6 Selection and Justification of the Process 22-23
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
Chapter 7 Detail study of Selected Process 24-27
7.1 Flow sheet for production of methoxyacetone 25
7.2 Process description 27
Chapter 8 Thermodynamics Feasibility 28-34
8.1 Gibbs free energy calculations 29
8.2 Heat of reaction calculations 34
Chapter 9 Conclusion & scope for future work 35-36
Chapter 10 References 37- 38
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
Chapter 1
ABSTRACT
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
PRODUCTION AND PLANT DESIGN FOR MANUFACTURE OF METHOXYACETONE
The study involves the synthetic methods of catalytic dehydrogenation of alkylene glycol ether to ether ketone or aldehyde is disclosed. The dehydrogenation is performed with copper chromite catalyst and at least 5 wt % of water based on alkylene glycol ether. It has been found that the selectivity to formation of ether ketone or aldehyde increases with increasing the amount of water in the alkylene glycol ether.
Methoxyacetone is a prime product with many useful intermediate. It is used as a polar organic solvent ,a chemical intermediate , a Schiff base reagent ,as an additive for cement construction and in cryogenic preservation of organs.
It has the IUPAC name - Methoxyacetone . It has the following synonyms, Methoxy-2-propanone, 1 –Methoxypropan-2-one.
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
Chapter 2
INTRODUCTION
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
The project involves designing and production of alkoxyacetone. In particular it involves
vapor phase oxidation of 1-alkoxy-2-propanol to alkoxyacetone using copper chromite catalyst.
It involves catalytic dehydrogenation of alkylene glycol ether to ether ketone or aldehyde. The
dehydrogenation is performed with copper chromite catalyst and water based on alkylene glycol
ether. It has been found that the selectivity to formation of ether ketone or aldehyde increases with
increasing the amount of water in the alkylene glycol ether.
In this vapor phase oxidation is carried out to avoid the use of hazardous hydrogen peroxide which
may be harmful if not handled with care. Thus oxidation or dehydrogenation along with multiple
distillation operation yields methoxyacetone.
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Applications
IUPAC name: Methoxyacetone.
It has the following synonyms: Methoxy-2-propanone,
Methoxypropan-2-one
Methoxyacetone (1-methoxy-2-propanone) provides a key to structural piece in the synthetic route to metolachlor and other herbicidal compositions (see, e.g., U.S. Pat. Nos. 4,666,502 and 5,576,188).
E.g. (U.S. Pat. No. 4,666,502)
Synthesis of heteroaromatic compounds bearing at one ring C-atom a N-substituted chloroacetylamino group, their use as herbicides, agricultural compositions. These compounds are particularly effective herbicides having an appropriate soil persis tence.
E.g. (U.S. Pat. No. 5,576,188)
Synthesis of hybridoma cell lines which produce said monoclonal antibodies and to immunological methods for detecting metolachlor in samples of soil, water or air using said monoclonal antibodies and to the test kits which can be used within the scope of these detection methods.
In addition, methoxyacetone has been used as a polar organic solvent, a chemical intermediate, a Schiff base reagent, an additive for cement 15 compositions, and as an aid in the cryogenic preservation of organs.
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
Chapter 3
LITERATURE SURVEY
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
The literature survey has been done on the basis of U.S patents. Development of entire
manufacturing and designing of plant process is based on these patents.
U.S patent – 3625836
Patent - Dec7, 1971
A method for recovering alkoxyacetones from mixtures of alkoxyacetone and the corresponding
1-alkoxy-2-propanol by adding water to the mixture and distilling to form a lower boiling
alkoxyacetone-water azeotrope.
U.S patent – 6376718
Patent – Nov 17, 2000
A catalytic dehydrogenation of alklyene glycol ether to ether ketone or aldehyde is disclosed.
The dehydrogenation is performed with copper chromite catalyst and at least 5 wt. % of water
based on alklyene glycol ether. It has been found that the selectivity to formation of ether ketone
or aldehyde increases with increasing the amount of water in the alkylene glycol ether.
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
Chapter 4
PROPERTIES OF CHEMICALS AND CATALYST
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PROPERTIES OF METHOXY-2-PROPANOL:
Physical State: Liquid
Appearance: Colorless liquid
Molecular Formula: C4H10O2
Molecular Weight: 90.12
Boiling Point: 120° C at 760 mm Hg
Melting Point: -95 ° C
Flash Point: 36.11 ° C
Vapor Pressure: 11.8 mm Hg at 25 °C
Vapor Density (Relative to Air): 3.11
Specific Gravity: 0.924 at 20°C
Water Solubility: greater than or equal to 100 mg/ml at18.89 ° C
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PROPERTIES FOR METHOXYACETONE:
Physical State: Liquid
Appearance: clear yellow
Molecular Formula: C4H8O2
Molecular Weight: 88.11
Boiling Point: 118 0C ( 760.00 mmHg )
Melting Point: -660C
Vapor Pressure: 16 (250C)
Vapor Density: 3.04
Specific Gravity/Density: 0.9570 g/cm3
Water Solubility: Miscible.
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
PROPERTIES OF COPPER CHROMITE:
Physical state: Solid
Appearance: gray-black tetragonal crystals
Molecular formula: Cr2CuO4
Molecular Weight: 311.08
Density: 4.5 g/cm3
Water Solubility: insoluble
Stability: air and moisture stable
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
PROPERTIES OF HYDROGEN:
Physical state: Gas
Appearance: Colorless gas
Molecular formula: H2
Molecular Weight: 2
Boiling point: - 252.8 °C
Melting point: - 259.2 °C
Density: 0.0899x10 -3 g.cm -3 at 20 °C
Solubility: Negligible
Stability: Highly flammable
(The gas mixes well with air, explosive mixtures are easily formed)
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Chapter 5
HEALTH & SAFETY ASPECTS
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Methoxyacetone:
Potential Health Effects
Eye: Causes eye irritation.
Skin: Causes skin irritation. May cause cyanosis of the extremities.
Ingestion: May cause gastrointestinal irritation with nausea, vomiting and diarrhea. Ingestion of
large amounts may cause CNS depression.
Inhalation: Causes respiratory tract irritation. Vapors may cause dizziness or suffocation.
Chronic: Prolonged or repeated skin contact may cause dermatitis. Effects may be delayed.
Safety Measures:
Eyes: Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting
the upper and lower eyelids. Get medical aid.
Skin: Get medical aid. Flush skin with plenty of water for at least 15 minutes while removing
contaminated clothing and shoes. Wash clothing before reuse.
Ingestion: Do not induce vomiting. If victim is conscious and alert, give 2-4 cupful’s of milk or
water.
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METHOXY-2-PROPANOL
Potential Health Effects
Vapor: Irritating to eyes, nose, and throat.
Liquid: Irritating to skin and eyes.
Health Hazard: Flammable and/or toxic gases are generated by the combination of alcohols
with alkali metals, nitrides, and strong reducing agents.
Safety Measures:
Eyes: Wear appropriate eye protection to prevent eye contact
Working Cloths: Work clothing that becomes wet should be immediately removed due to its
flammability hazard (i.e. for liquids with flash point < 100°F)
First Aid:
EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or
normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison
control center. Do not put any ointments, oils, or medication in the victim's eyes without specific
instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a
hospital even if no symptoms (such as redness or irritation) develop.
SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all
contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If
symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be
prepared to transport the victim to a hospital for treatment.
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INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If
symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or
chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide
proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible,
Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of
protection greater than or equal to that advised under Protective Clothing.
INGESTION: DO NOT INDUCE VOMITING. If the victim is conscious and not convulsing,
give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison
control center. Be prepared to transport the victim to a hospital if advised by a physician. If the
victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's
airway is open and lay the victim on his/her side with the head lower than the body. DO NOT
INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital.
Fire Hazard
Air & Water Reactions: Highly flammable. Soluble in water. Oxidizes readily in air to form
unstable peroxides that may explode spontaneously.
Fire Hazard: FLAMMABLE. Flashback along vapor trail may occur. Vapor may explode if
ignited in an enclosed area.
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
HYDROGEN
Potential Health Effects
Eyes: Contact with rapidly expanding gas may cause burns or frostbite. Contact with cryogenic
Liquid can cause frostbite and cryogenic burns.
Skin: Contact with rapidly expanding gas may cause burns or frostbite. Contact with cryogenic
Liquid can cause frostbite and cryogenic burns.
Accidental release measures
Personal precaution: Immediately contact emergency personnel. Keep unnecessary personnel
away. Use suitable protective equipment. Shut off gas supply if this can be done safely. Isolate
area until gas has dispersed.
Environmental precautions: Avoid dispersal of spilled material and runoff and contact with
soil, waterways, drains and sewers.
Methods for cleaning up: Immediately contact emergency personnel. Stop leak if without risk.
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
Chapter 6
METHOD OF PRODUCTION
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
Methoxyacetone is mainly formed by catalytic dehydrogenation process. It is carried in
following ways:
1. By dehydrogenation of 1-methoxy-2-propanol in presences of hydrogen peroxide
in liquid phase.
2. By dehydrogenation of 1-methoxy-2-propanol in presence of copper chromite in
vapor phase.
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Chapter 7
SELECTION AND JUSTIFICATION OF PROCESS
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
The dehydrogenation of 1-methoxy-2-propanol in presence of copper chromite in vapour
phase is carried out. This is because of following reasons:
1. Copper chromite catalyst can be easily prepared.
2. Risk of handling hazardous hydrogen peroxide is avoided.
3. Easy separation of mixture product.
4. Toluene used as n entrainer can be easily recovered
5. Hydrogen gas separated is flared
6. Mild conditions ,simple equipment design and reagents are readily available
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
Chapter 8
Detail study of Selected Process
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
PROCESS DISCRIPTION
1. The process involves catalytic dehydrogenation 1-methoxy-2-propanol to methoxy
acetone. This is generally a vapor-phase oxidation using copper chromite as a catalyst.
2. At start 1-methoxy-2-propanol and water in proportions are mixed and mixture is send to
thin film evaporator. The heat exchanger is used to increase the temperature above the
desired range. In evaporator steam is used as a heating medium. The temperature of about
140 °C is reached. The vapors formed are reheated in heat exchanger to about 290°C
using dowtherm oil.
3. The vapors are sent to catalytic dehydrogenation unit. The unit is a fixed bed reactor
using copper chromite as a catalyst .Reactor is provided with jacket. Heating oil mainly
dowtherm oil is used. The temperature of the oil is about 280°C. Dehydrogenation is
carried out and crude product is obtained from the bottom.
4. The crude product from reactor contains mixture of water, methoxyacetone, hydrogen
gas, methoxy-2-propanol. The product stream is passed through the condenser. Cooling
water is used as the medium. Two condensers are used for effective temperature
difference.
5. The condensate contains liquid-gas mixture, thus they are sent to gas-liquid separator.
Here gas liquid separation results, and released hydrogen gas is flared.
6. The condensate liquid obtained contains mixture of water, methoxyacetone and some
amount of unreacted 1-methoxy-2-propanol. The mixture is subjected to distillation for
separation.
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
7. Distillation of feed mixture to distillation unit is carried out .various cuts are obtained
from the separation unit. They are as follows
Low boiling impurities Methoxyacetone + water azeotrope Methoxy-2-propanol + water Methoxyacetone + water + methoxy-2-propanol
8. Methoxy-2-propanol + water is recycled back and sent to heat exchanger. Methoxyacetone + water forms a binary azeotrope which is subjected to further azeotropic distillation.
9. In order to alter the volatility toluene or benzene are used as an entrainer
10. Here toluene is used has an entrainer as benzene is carcinogenic. Toluene alters the
volatility and forms a lower boiling azeotrope with water and methoxyacetone is
separated out.
11. The mixture is condensed and separated out and methoxyacetone is recovered.
12. Toluene + water are then subjected to further separation from which toluene is recovered
and water is send to ETP plant.
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
Chapter 9
THERMODYNAMICS FEASIBILITY
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
REACTION OF METHOXY-ACETONE
CH3-CH (OH)-CH2-O-CH3 CH3-CO-CH2-O-CH3 + H2
(METHOXY-2-PROPANOL) (METHOXY-ACETONE)
CONVERSION = 70% / PASS
SELECTIVITY = 97.5%
AS,
YIELD = CONVERSION x SELECTIVITY
= 0.7 x 0.975
= 0.68
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
RAW MATERIAL:
METHOXY 2-PROPANOL
MOLECULAR WEIGHT: 90
MOLECULAR FORMULA: CH3-CH(OH)-CH2-O-CH3
Domalsk-Hearing group contribution values for std. state thermal properties
Perry's Chemical Engineers Handbook-8th Edition
GROUP n∆H
Of
(KJ/mole)
∆SO
(J/mol. K)
∆Hsf
(KJ/mole)
S(J/mol. K)
C-(3H)(C) 1 -42.26 127.32 -47.61 80.30
C-(2C)(H)(O) 1 -26.1 -43.05 -27.6 -29.83
C-(2H)(C)(O) 1 -32.9 43.43 -35.8 32.89
C-(3H)(O) 1 -42.26 127.32 -47.61 83.3
O-(C)(H) 1 -159.33 121.5 -191.5 43.89
TOTAL-302.85 376.52 -350.12 213.25
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
PRODUCT:
METHOXY ACETONE
MOLECULAR WEIGHT: 88
CHEMICAL FORMULA: C4H8O2
Domalsk-Hearing group contribution values for std. state thermal properties
Perry's Chemical Engineers Handbook-8th Edition
GROUP n∆H
Of
(KJ/mole)
∆SO
(J/mol. K)
∆HS
f
(KJ/mole)
S(J/mol. K)
C-(3H)(C) 1 -42.26 127.32 -47.61 83.3
CO-(2C) 1 -132.67 64.31 -152.76 33.81
C-(2H)(C)(O) 1 -32.9 43.43 -35.8 32.5
C-(3H)(O) 1 -42.26 127.32 -47.61 83.
TOTAL-250.01 302.38 -283.78 233
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
STANDARD HEAT OF FORMATION AT 298.15 K:
∆HSf = [-283.78] – [- 350.12]
= 66.34 Kj/mol
GIBBS FREE ENERGY:
∆GSf = ∆HS
f- T∆SS
= 66.34 – 298.15 X [233 – 213.25]
= -5822.12 Kj/mol
HEAT CAPACITY OF LIQUID AND VAPOR MIXTURES CAN BE ESTIMATED AS MOLE FRACTION OF THE PURE COMPOUND VALUES
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
c
Cpm = ∑ Xi Cpi
i=1
IDEAL HEAT CAPACITY AT REACTION TEMPERATURE: 2800C (553 K)
A. METHOXY-2-PROPANOL(MEPA)
Benson* and CHETAH Group Contributions for Ideal Gas Heat Capacity. Perry's Chemical Engineers Handbook-8th Edition
GROUP n Cp 553 K (J/mol k) C-(3H)(C) 1 42.26 C-(2C)(H)(O) 1 35.52 C-(2H)(C)(O) 1 37.105 C-(3H)(O) 1 42.26 O-(C)(H) 1 21.035 TOTAL 178.38
B. METHOXY ACETONE (MEA)
Benson* and CHETAH† Group Contributions for Ideal Gas Heat Capacity. Perry's Chemical Engineers Handbook-8th Edition
GROUP n Cp 553 K (J/mol k) C-(3H)(C) 1 42.56 CO-(2C) 1 21.455 C-(2H)(C)(O) 1 37.105 C-(3H)(O) 1 42.26 O=C 1 15.07 TOTAL 158.145
• CpMEPAAT 553 K = 0.178 KJ/ mol. K
• CpMEAAT 553 K = 0.158 KJ/ mol. K
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
∆HOMEPA AT 553 K = Hf298.15 + Cp ∆ T
= -350.12 + 0.178(553 -298.15)
= -304.76 KJ/mol
∆HOMEA AT 553 K = Hf298.15 + Cp ∆ T
= -283.78 + 0.158(553 -298.15)
= -243.5 KJ/mol
∆H 353K = ∆Hfproduct – ∆Hfreactant
= [-243.5] – [- 304.76]
= 61.25 KJ/mol (i.e. endothermic)
∆H 353K = 61.23 X 103 J/mol
= 61.23/ (4.187 X 10-3 X 88)
= 166.23 Kcal/kg
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Chapter 10
CONCLUSION AND FUTURE WORK
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
Thus vapor phase oxidation of 1-methoxy-2-propanol to methoxyacetone
using catalyst is studied. Higher conversion of alcohol to ketone and good
selectivity is obtained.
The Process is thermodynamically feasible and thus future work of the process is
feasible. Future work includes design and costing of entire manufacturing process
of methoxyacetone. Thus detailed study of development of entire process is
necessary for future scope.
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Chapter 11
REFERENCES
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PRODUCTION AND PLANT DESIGNFOR MANUFACTURE OF METHOXYACETONE
* Perry's Chemical Engineers Handbook-8th Edition
* Coulson & Richardson's Chemical Engineering. Vol. 6
* http://www.chemspider.com
* http://www.freepatents.com
* http://www.wikipedia.com
* US Balan’s Patent (Patent No.6376718)
*US Patent (Patent No. 3625836)
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