A Green Chemistry Module

Petretec – Dupont’s Technology for Polyester Regeneration

Presidential Green Chemistry Challenge Award

World Proven Reserves of Crude Oil

63.7

89.5

20.6

74.9

65.4

44.0675.7

thousand million barrels

World Proven Crude Oil Reserves

as percent of 1296 thousand million barrel total

Composition of Crude Oil

CRUDE OIL

HYDROCARBONS NON-HYDROCARBONS

ALIPHATICS AROMATICS NAPHTHENES SULFURS NITROGENS OXYGENS METALLICS

25% 17% 50% <8% <1% <3% <100PPM

C1 - C60 (C6H5)n CYCLOALKANESSH

S

NH

O

COOH

Crude Oil Classification

PETROLEUMSaturates

Aromatics

Asphalticsn-alkanes C5 - C44

branched alkanescycloalkanes (napthenes) single ring

condensed ring

nitrogenoxygensulfur

containing compounds

API Gravity = 35o

The Uses of Crude Oil

The Xylenes

Boiling Point 144oC 139.3oC 137-138oC Melting Point -25oC -47.4oC 13-14oC

ortho meta para

CH3

CH3

CH3

CH3

CH3

CH3

CRUDE

DESALTING

REFINING

REFORMING

BLENDING

Distillation to separate by boiling point ranges

Water washing to remove impurities

Conversion reactions to alter molecular structures

Mixing to obtain maximum commercial characteristics

Petroleum delivered from well field

Petroleum Refining

GAS

LIGHT NAPHTHA

HEAVY NAPHTHA

KEROSENE

ATM. GAS OIL

RESIDUUM

CRUDE DESALTER FURNACE

C1-C4

bp < 50 oF

C5 - C?

bp 50-200oF

C? - C12

bp 200-400oF

C12 - C16

bp 400-500oF

C15 - C18

bp 500-650oC

> C20

bp >650oF

TOWER

Distillation – separation by boiling point

Petroleum ReformingGAS

LIGHT NAPHTHA

HEAVY NAPHTHA

KEROSENE

ATM. GAS OIL

RESIDUUM

TOWER

FUEL GAS

TREATER

HYDROTREATER

HYDROTREATER

HYDROTREATER

REFORMER AROMATIC EXTRACTION

CATALYTICCRACKER

JET FUELS/KEROSENE

DIESEL & FUEL OILS

GASOLINE

AROMATICS

VacuumDistillation

VACUUM GAS OIL

LUBRICATING OIL

COKER COKE

ASPHALT

CATALYTICCRACKER

Conversion Reactions

gasoline gasoline additive recycle

C7H15.C15H30.C7H15 C7H16 + C7H14 + C15H30CRACK

COMBINE

REARRANGE

THERMAL

CATALYTIC

ALKYLATION

POLYMERIZATION

REFORMIING

ISOMERIZATION

CH3CH2CH3 CH2 CH CH2 CH3CH3CH2CH2 CH2CH2CH2CH3

C H3C

CH3

CH2C H3C

CH3

CH2C H3C

CH3

CH3

C CH2

CH3

H

CH2C CHCH3

CH3CH3

CH3

H3CC

82% 18%

Dehydrogenation

Dehydroisomerization

Isomerization

Dehydrocyclization

Hydrocracking

Catalytic Reforming – Conversion ReactionsDehydrogenation of cycloalkanes to aromatics

Dehydroisomerization of cyclopentanes to aromatics

Isomerization of alkanes

Dehdrocyclization of alkanes

Hydrocracking of alkanes

CH3 CH3

3H2

CH3

3H2

CH3CH2CH2CH2CH3 CHH3C

CH3

CH2 CH3

CH3CH2CH2CH2CH2CH2CH3

CH3

4 H2

CH3CH2CH2CH2CH2CH2CH3 CH3CH2CH3 CH3CH2CH2CH3

Preparation of PET monomers

CH2H2CO2

Ag

OCHH3C

OH

CH

OH

CH3

C H 3

C H 3

[ O 2 ]

C

C

O

O O H

O H

T A

C H 3 OH C H 3 OH / C o O 2

C

C

O

O

O C H 3

O C H 3

D MT

Formation of ethylene glycol

Formation of TA and DMT

PET Polymerization Reactions

C

O

CH3O C

O

OCH3 2n CH2HO CH2 OH

low Temp - 2n CH3OH

C

O

C

O

CH2HO CH2 O CH2O CH2 OH

C

O

C

O

CH2O CH2 O

n

n

CO

HOC

O

OHCH2HO CH2 OH

n

n CH2O CH2 Ohigh Temp

-H2OC

O

C

O

n

Step Growth Polymerization - Condensation

Ester Interchange - Transesterification

The Dupont

Petretec

Process

For

Polyester

Regeneration

SCRAP PET

Contaminated PET PET for Recycling

Landfill/Incinerate Mechanical Recycling PET / DMT

solution

DMTTemp > 220oC

METHANOLYSIS REACTORCH3OH, 260-300

oC, 340-650kPa

DMT + Ethylene Glycol excess CH3OH

Methanol removal column

CH3OH DMT / Ethylene Glycol azeotrope

MPTdistillation

MPT / Ethylene Glycol

Ethylene Glycol / MPT

DMT

Pure DMTdistillation

Petretec Polyester Regeneration

C

O

C

O

CH2O CH2 O n

n

CH2HO CH2 OHCO

COCH3OH

n

CH3O OCH3

Methanolysis Reactor

260-300oC 340-650 kPa