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CH0204 Organic Chemical Technology
Lecture 8
Chapter 2 Synthe1c Organic Chemicals
Balasubramanian S Assistant Professor (OG) Department of Chemical Engineering
1 Balasubramanian S
Chapter 2 SYNTHETIC ORGANIC CHEMICALS
Methanol and Formaldehyde
Ethylene dichloride and vinyl chloride
Isopropanol and acetone
Benzene
1
2
Overview of topics
17/02/11 2
3
Balasubramanian S
4
Chapter 2 SYNTHETIC ORGANIC CHEMICALS
Methanol and Formaldehyde
Ethylene dichloride
1
2
Overview of topics
3 Balasubramanian S
Methanol
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Methanol (CH3OH)
Methanol, also known as methyl alcohol, wood alcohol, wood
naphtha or wood spirits, is a chemical with formula CH3OH
(oWen abbreviated MeOH).
It is the simplest alcohol, and is a light, vola1le, colorless,
flammable, liquid with a dis1nc1ve odor that is very similar to
but slightly sweeter than ethanol (drinking alcohol).
Methanol
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Raw materials
• Synthesis gas (Star1ng material)
• KMNO4 – removes the traces of ketones, aldehydes and
other impuri1es
• Steam
Methanol
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Methods of produc;on
• Cataly1c hydrogena1on of carbon monoxide (Synthesis gas)
• Oxida1on of LPG (Propane and Butane) Chemical Reac;ons (exothermic)
Main reac1on : CO + 2H2 CH3OH; ΔH = -‐26.4 kcal
Side reac1on : CO + 3H2 CH4 + H2O; ΔH = -‐50.0 kcal
2CO + 2H2 CH4 + CO2; ΔH = -‐60.3 kcal
Methanol
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Recycle gas from storage Tank
Process
CO+H2 (Synthesis Gas)
KMnO4
Catalysts: Oxides of Zn, Cr, and Mg
Water and Steam
Methanol
Heavy Alcohols
Ether
Methanol
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Catalyst Used: Oxides of Zn, Cr, and Mg
Compressor 200 – 350 atm
300 – 375 deg. C
Cooler
Storage Tank
De pressurized Methanol Tower
CSTR (Traces of Ketones and
Aldehydes are removed)
(Dimethyl ether)
2.25 mole ra1o of CO + H2
Feed and Recycle gas mix point
Condenser
Reboiler
Reboiler
Condenser
Methanol
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Uses of Methanol
Used to manufacture formaldehyde
Used as solvent in laboratories
Used to manufacture silicones (Methyl chloride)
Used in the fuel cells
Used as an an1-‐freezing agent in pipelines
Formaldehyde
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Formaldehyde (HCHO or CH2O) Formaldehyde is a colorless gas with a characteris1c pungent odor. It is an important precursor to many other chemical compounds, especially for polymers. Raw materials • Methanol • Air • Water
Formaldehyde
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Methods of produc;on
• Cataly1c oxida1on and dehydrogena1on of methanol
• Oxida1on of Methane or LPG (Propane and Butane)
• Pyrolysis Chemical Reac;ons (Exothermic oxida;on and Endothermic dehydrogena;on)
Oxida1on : CH3OH + ½ O2 HCHO + H2O; ΔH = -‐37.4 kcal
Dehydrogena1on : CH3OH HCHO + H2; ΔH = +50.0 kcal
Methanol + Oxygen Formaldehyde + Water
Methanol Formaldehyde + Hydrogen
Formaldehyde
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Catalyst: Oxides of Ag and Cu Pressure: 0.2 atm 450 – 600 OC
Methanol to Air Ra1o: 30 – 50%
Preheater
Preheater
15% Unconverted methanol
Formaldehyde
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Uses of Formaldehyde
Used to manufacture phenolic resins
Used to manufacture urea
Used to manufacture melamine resins
Chapter 2 SYNTHETIC ORGANIC CHEMICALS
Methanol and Formaldehyde
Ethylene dichloride
1
2
Overview of topics
14 Balasubramanian S
Chapter 2 SYNTHETIC ORGANIC CHEMICALS
Methanol and Formaldehyde
Ethylene dichloride
1
2
Overview of topics
15 Balasubramanian S
Ethylene dichloride
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Ethylene dichloride (C2H4Cl2), is a chlorinated hydrocarbon,
mainly used to produce vinyl chloride monomer (VCM,
chloroethene), the major precursor for PVC produc1on.
It is a colorless liquid with a chloroform-‐like odor.
Ethylene dichloride
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Raw materials
• Ethylene • Chlorine
• Ethylene di bromide catalyst
• Caus1c (NaOH)
Ethylene dichloride
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Methods of produc;on
• Reac1on of chlorine with ethylene in liquid or vapor phase
• By-‐product of chlorinated hydrocarbons
Chemical Reac;ons
Chlorina1on : CH2= CH2 + Cl2 ClCH2 . CH2Cl
Ethylene Ethylene dichloride Chlorine
Ethylene dichloride
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Ethylene dichloride
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Uses of Ethylene dichloride Used in the produc1on of vinyl chloride monomer (VCM, chloroethene) with hydrogen chloride as a byproduct.
VCM is the precursor to polyvinyl chloride.
Used as solvent.
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1. Dryden C. E, Outlines of Chemical technology – for the 21st Century, 3rd edi1on, East-‐West Press (2004)
2. Aus1n G. T, Shreve’s Chemical Process Industries, 5th edi1on, Mc Graw Hill Interna1onal edi1ons (1984)
3. Finar IL, Organic Chemistry Vol. 1 6th Edi1on Pearson Educa1on 2009 pp.116-‐117
References
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Thank you