A Green Chemistry Module
Petretec – Dupont’s Technology for
Polyester Regeneration
Presidential Green Chemistry Challenge Award
World Proven Reserves of Crude Oil
20.6 65.4
63.7
44.0
675.7
74.9
89.5
thousand million barrels
World Proven Crude Oil Reserves
North America
6%
Middle East
66%
South & Central
America
9%
Europe
2%
Africa
7%
Former Soviet Union
6%
Asia & Pacific
4%
as percent of 1296 thousand million barrel total
Composition of Crude Oil
CRUDE OIL
HYDROCARBONS
ALIPHATICS
25%
C1 - C60
AROMATICS
17%
(C6H5)n
NON-HYDROCARBONS
NAPHTHENES
50%
CYCLOALKANES
SULFURS
<8%
NITROGENS
<1%
OXYGENS
<3%
<100PPM
O
SH
N
H
S
METALLICS
COOH
Crude Oil Classification
PETROLEUM
Asphaltics
Saturates
n-alkanes C5 - C44
branched alkanes
cycloalkanes (napthenes)
Aromatics
single ring
condensed ring
nitrogen
oxygen
sulfur
containing compounds
Ot he r
10%
S a t ur a t e s
A spha l t i c s
25%
8%
A r om a t i c s
7%
API Gravity = 35o
N a pht he ne s
50%
The Uses of Crude Oil
Uses of Crude Oil
Uses of Crude Oil
Gasoline
Kerosene Jet Fuel
Gasoline
Liquefied Refinery Gases
Kerosene
Jet Fuel
Coke
Liquefied Refinery Gases
Coke PETROCHEM ICAL FEEDSTOCKS
Kerosene
PETROCHEMICAL
FEEDSTOCKS
Kerosene
Distillate Fuel Oil
Residual Fuel Oil
Distillate
Fuel Oil
Still Gas
Residual Fuel Oil
Asphalt and Road Oil
Still
Gas
Lubricants
Asphalt and Road Oil
Other
Lubricants
Other
The Xylenes
CH3
CH3
CH3
CH3
CH3
ortho
Boiling Point
Melting Point
144oC
o
-25 C
meta
139.3oC
o
-47.4 C
CH3
para
137-138oC
o
13-14 C
CRUDE
Petroleum delivered from well field
DESALTING
Water washing to remove impurities
REFINING
REFORMING
BLENDING
Distillation to separate by boiling point
ranges
Conversion reactions to alter
molecular structures
Mixing to obtain maximum commercial
characteristics
Petroleum Refining
GAS
CRUDE
DESALTER
FURNACE
T
O
W
E
R
C1-C4
bp < 50 oF
C 5 - C?
LIGHT NAPHTHA
bp 50-200oF
HEAVY NAPHTHA
KEROSENE
ATM. GAS OIL
RESIDUUM
C? - C12
bp 200-400oF
C12 - C16
bp 400-500oF
C15 - C18
bp 500-650oC
> C20
bp >650oF
Distillation – separation by boiling point
Petroleum Reforming
FUEL GAS
GAS
T
O
W
E
R
LIGHT NAPHTHA
TREATER
GASOLINE
HEAVY NAPHTHA
KEROSENE
ATM. GAS OIL
REFORMER
HYDROTREATER
AROMATIC
EXTRACTION
AROMATICS
JET FUELS/KEROSENE
HYDROTREATER
HYDROTREATER
CATALYTIC
CRACKER
DIESEL & FUEL OILS
RESIDUUM
VACUUM GAS OIL
Vacuum
Distillation
CATALYTIC
CRACKER
LUBRICATING OIL
ASPHALT
COKER
COKE
Conversion Reactions
THERMAL
CRACK
C7H15.C15H30.C7H15
C7H16 +
gasoline
C7H14 +
C15H30
gasoline additive
recycle
CATALYTIC
ALKYLATION
CH3CH2CH3
CH2 CH
CH3CH2CH2
CH2 CH3
CH2CH2CH2CH3
COMBINE
82%
POLYMERIZATION
H3C
C
CH2 H3C
CH3
REFORMIING
C
CH2
H3C
CH3
C
18%
H
CH3
CH2
CH3
C
CH3
CH2
CH3
Dehydrogenation
Dehydroisomerization
REARRANGE
Isomerization
ISOMERIZATION
Dehydrocyclization
Hydrocracking
H3C
C
CH
CH3
C
CH3
CH3
Catalytic Reforming – Conversion Reactions
Dehydrogenation of cycloalkanes to aromatics
CH3
CH3
3H2
Dehydroisomerization of cyclopentanes to aromatics
CH3
3H2
Isomerization of alkanes
CH3
CH3CH2CH2CH2CH3
Dehdrocyclization of alkanes
H3C CH CH2 CH3
CH3
CH3CH2CH2CH2CH2CH2CH3
4 H2
Hydrocracking of alkanes
CH3CH2CH2CH2CH2CH2CH3
CH3CH2CH3
CH3CH2CH2CH3
Preparation of PET monomers
Formation of ethylene glycol
H2C
CH2
O2
Ag
OH OH
O
H3C
CH CH CH3
Formation of TA and DMT
O
C H3
OH
C
[ O2 ]
C H3
C
C H OH
O2 3
C H 3 OH / C o
O
OC H3
C
C
O
OC H3
D MT
O
OH
TA
PET Polymerization Reactions
Step Growth Polymerization - Condensation
O
C
n
HO
O
C
high Temp
n HO CH2 CH2 OH
-H2O
OH
O
O
C
C
O CH2 CH2 O
n
Ester Interchange - Transesterification
O
O
C OCH3 2n HO CH2 CH2 OH
n CH3O C
low Temp
HO CH2 CH2 O
- 2n CH3OH
O
O
C
C
O CH2 CH2 OH

O
O
C
C
O CH2 CH2 O
n
SCRAP PET
The Dupont
Petretec
Process
For
PET for Recycling
Contaminated PET
DMT
o
Temp > 220 C
Landfill/Incinerate
Mechanical
Recycling
PET / DMT
solution
METHANOLYSIS REACTOR
o
CH3OH, 260-300 C, 340-650kPa
DMT + Ethylene Glycol
excess CH3OH
Methanol removal column
Polyester
Regeneration
CH 3OH
DMT / Ethylene Glycol
azeotrope
MPT
distillation
MPT / Ethylene Glycol
DMT
Ethylene Glycol / MPT
distillation
Pure DMT
Petretec Polyester Regeneration
Methanolysis Reactor
O
O
C
C O CH2 CH2 O
O
n C
CH3O
CH3OH
n
260-300oC
340-650 kPa
O
C
n HO CH2 CH2 OH
OCH3