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HYDROCARBON PROCESSING GASOLINE COMPONENTS
English version based on the presentation of
Prof. Dr. Jenő Hancsók, D.Sc.
held on 15.10.2014
Pannon University MOL Crude Oil and Coal Technology Department
MOL Ásványolaj- és
Széntechnológiai Intézeti
Tanszék
Vegyészmérnöki- és
Folyamatmérnöki Intézet
8200 Veszprém, Egyetem u. 10. Pf. 158.
Tel.: +36 88/624217 Fax.:+36 88/624520
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright 2
Motor gasolines
blending components additives
3 3
Motor gasolines
Blending components
Motor gasolines
Reformate
Alkylate
Isomerate
Oligomer gasolines
Straight rum gasoline
FCC gasoline
Hydrocrack gasoline
Alternative components
Gasolines
formed as
co-products
Ad
ditiv
es
Oxygenate
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
4 4
Light naphtha isomerisation
5 5
Light naphtha isomerisation
Light naphtha (~30-40/45-82°C) isomerisation products
Light naphtha: C5-C6 hydrocarbons (C7
6 6
Goal of C5/C6 fraction isomerisation
Production of high octane light gasoline fractions
(ΔRON: 26-56 unit)
Sometimes pure isopentane production as feed for isoprene-
production
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Kís
érle
ti o
ktá
nsz
ám
(K
OS
Z)
Forráspont, °C
-20
0
20
40
60
80
100
120
140
-20 0 20 40 60 80 100 120 140 160 180
többszörös elágazású
izoparaffinok
n-paraffinok
naftének
olefinek
aromások
7 7
Boiling point-RON correlation of different
hydrocarbon types
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
aromatics
olefins
n-paraffins
naphthenes
multi-branched
isoparaffins
Boiling point, °C
RO
N
8 8
Thermodynamics of C5/C6 paraffin
isomerisation
Paraffin hydrocarbon Reaction heat (25°C), kJ/mol
from n-pentane
2,2-dimethyl-propane -19,93
2-methyl-butane -8,04
from n-hexane
2,2-dimethyl-butane -18,39
2,3-dimethyl-butane -10,59
2-methyl-pentane -7,12
3-methyl-pentane -4,44
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
9 9
Equilibrium concentration of pentane and
hexane isomers
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
10 10
RON of C5 and/or C6 hydrocarbons equilibrium
mixtures (open chained)
60
70
80
90
100 150 200 250 300
Hőmérséklet, °C
Kís
érle
ti o
ktá
nszá
m .
C5-paraffinok
C5/C6-paraffinok
C6-paraffinok
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Temperature, °C
RO
N
C5 paraffins
C6 paraffins
C5/C6 paraffins
11 11
Catalysts for C5/C6 paraffin isomerisation
Hydroisomerisation catalysts
Temperature of
favourable activity:
High
≥300°C
Pt(0,5-0,6)/g-Al2O3/F
F: 3-4%
Medium
200°C-300°C
Pt(0,3-0,5)/H-Y zeolite
Pt(0,3-0,5)/H-Mordenite
Low
≤200°C
Pt(0,3-0,4%)/Al2O3/chloride (7-10%)
Pt/sulphated metal-oxide
Mixed metal-oxide
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
12 12
General mechanism of n-C5/n-C6 paraffins
isomerisation on bifunctional catalysts
-H2 Diffúzió +H+
n-P n-O n-O n-C+
+H2 Diffúzió -H+
i-P i-O i-O i-C+
fémes
hely
savas
hely
krakk
termékek
-H2 Diffúzió +H+
n-P n-O n-O n-C+
+H2 Diffúzió -H+
i-P i-O i-O i-C+
fémes
hely
savas
hely
krakk
termékek
n-P: n-paraffin; n-O: n-olefin; n-C+:n-carbenium-ion;
i-C+: iso-carbenium-ion; i-O: iso-olefin; i-P: iso-paraffin
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Diffusion
Diffusion
Metallic
site Acidic
site
Cracked
products
13 13
Classification of isomerisation processes
According to operation temperature:
Low (kb. ≤ 200°C)
Medium (kb. 200-300°C)
High (>300°C)
After 1990, only these
processes were implemented
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
14 14
Adventages of low temperature isomerisation
Feed and energy efficiency (CO2 ↓)
Higher isoparaffin yield
Higher RON (2-5 unit)
Lower hydrogen consumption (CO2 ↓)
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
15 15
Catalytic reforming
16
Catalytic reforming
Goal: production of high octane blending components and/or
production of hydrocarbon mixture suitable for individual aromatics
recovery
Feed: sulphur free( 1 mg S/kg) straight run and/or hydrocracking
and/or other gasoline fractions
16 Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
17
Main reactions I.
17
Dehidrogénezés Hőszínezet
cikloparaffin aromás H= +205 kJ/mol
+ 3 H2
sűrűség, g/cm
3 0,7694 0,8669
KOSZ: 73,8 119,7
paraffin olefin H= +90 kJ/mol + H2
sűrűség, g/cm
3 0,6838 0,7026
KOSZ: 0 89,8
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Specific gravity, g/cm3
RON:
Specific gravity, g/cm3
RON:
Specific gravity, g/cm3
RON:
Dehydrogenation cycloparaffin aromatic
Reaction heat
18
Main reactions II.
18
Dehidrociklizáció H= +238 kJ/mol
+ 4 H2
sűrűség, g/cm
3 0,6838 0,8669
KOSZ: 0 119,7
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Specific gravity, g/cm3
RON:
Dehydrocyclisation
19
Main reactions III.
19
Izomerizáció H= -4,4 kJ/mol
n-paraffin i-paraffin
sűrűség, g/cm
3 0,6838 0,6871
KOSZ: 0 52,0
C5-cikloparaffin C6-cikloparaffin
sűrűség, g/cm
3 0,7913 0,7694
KOSZ: 100,4 73,8
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Specific gravity, g/cm3
RON:
Specific gravity, g/cm3
RON:
Isomerisation n-paraffin i-paraffin
C5 cycloparaffin C6 cycloparaffin
20
Side reactions I.
20
Hidrokrakkolás
+ H2
+ H2
C1+
C2+
C3+
Hidrodezalkilezés
+ H2C1+
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Hydrocracking
Hydrodealkylation
21
Side reactions II.
21
Alkilezés
+
Diszproporcionálódás
2 +
Kokszképződés
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Alkylation
Disproportioning
Coke formation
22
Volume-yield correlation during different feed
(fixed bed process)
22 Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
23
Catalysts for reforming
23
Megnevezés Relatív aktivitás
Króm-oxid 1
Molibdén-oxid 10
Pt/Al2O3/Cl (1953)
(Cl: 0,8-1,3%)
100
Többfémes (1967)
(Pt: 0,2-0,75%- és
Re, Sn, Ir, Ge, Rh: 0,01-től 0,3-0,5%-ig)
Stabilabb és
szelektívebb
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Catalyst Relative activity
Chromium-oxide
Molibdenum-oxide
Multi metallic (1967) More stable
and
more selective
24
Process parameters
Temperature: 480 – 520 °C
Pressure: 5 – 20 bar
LHSV: 1,5 – 3,0 m3/m3h
H2/hydrocarbon molar ratio: 5:1 – 12:1
24 Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
25
Industrial implementation of reforming
Reactors
number: 3-5
Fixed bed
(radial – lower pressure drop – or axial flow)
Moving bed (CCR – continuous catalyst
regeneration)
Construction material:
Resistant to reducing and oxidizing atmosphere
temperature: 550°C - ig
pressure: 5-25(35) bar
25 Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
26
Conventional (fixed bed) reformer process
26 Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
27
Continuous catalyst regeneration process
27 Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
28
Product yield structure and characteristics
28 Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Products Yield, % Characteristics
Hydrogen rich gas 7-10 Hydrogen concentration 60-80 vol%
fuel gas (C1-C2) 1-3
propane 3-5
butene 5-8 ~50% i-butane
reformate 74-84
RON: 97-101
MON: 86-88
FBP: 20-40°C higher than the feed
aromatic content: >60%
specific gravity: 0,76-0,79 g/cm3
29 29
Alkylation
30 30
Chemistry of alkylation
Közvetlen eljárások
C3=
iC4 + C4=
C5=
Közvetett
C3=
iC4= + C4= + H2
C5=
*katalizátor: foszforsav szilárd hordozón, savas ioncserélő gyanták
**katalizátor: olefin hidrogénező (pl. Pd/Al2O3, NiMo/Al2O3)
Alkilátum
HF vagy H2SO4
Szupersavak szilárd hordozókon
katalizátor* katalizátor**
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Direct processes
Indirect processes Alkylate
HF or H2SO4
Catalyst* Catalyst**
Catalyst*: phosphorous acid on solid support (acidic ion exchange resins
Catalyst**: olefin hydrogenation (e.g. Pd/Al2O3, NiMo/Al2O3
31 31
Chemistry of alkylation
Reactions:
Via tertiary carbenium ion, chain mechanism
Initiating step
e.g. proton addition onto isobutene in the presence of strong acid
Addition step
Chain producing reaction
Chain closing reaction C C CC
C C C
C
+
H++
C C C
C
C
C
C
C C C C
C
C C C
C
C
C
C
C C C C
C+
++
+
2,2,4-TMP
C C C
C
C C C
C
C C C
C
C
C
C
C++
+
C C C
C
C C C
C
+ H++
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
32 32
Thermodynamics of alkylation
Exothermic reactions
(-630)-(-480) kJ/kg alkylate (depending on the olefin)
Temperature favouring production of higher octane C7-C8 isoparaffins:
~ 10°C (H2SO4)
~ 35°C (HF)
Higher temperature polymerisation reaction
boiling range increases RON decreases
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
33 33
Process parameters of alkylation
Main goal: suppress the reaction of olefins with each other
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Parameter HF H2SO4 Solid acid
Reactor temperature, °C 25-45 6-10 100-250
Pressure, bar 20 15 20-50
Isobutane: olefin ratio, vol%/vol% 15-20 10-15 5-8
Acid concentration, % 58-90 98-99 -
Acid in the mixture, % 50-70 50-75 -
Acid consumption, kg/t alkylate 0,4-0,7 35-150 -
34 34
Products of alkylation
Products
Isoparaffins with carbon number of the sum of the starting isoparaffin and olefin
Premium blending components
Aromatic content 0
Olefin < 0,1%
Good vapour pressure
High RON ( ≥ 93)
Low sensitivity [ +1 (-) +4 ]
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
35 35
Product composition and RON/MON of
different alkylation process products
0%
20%
40%
60%
80%
100%
HF H2SO4 Szilárd sav
C9+
C8
C6-C7
C5
95,7
94,2 95,6
93,6
97,0
93,2
KOSZ:
MOSZ:
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Solid acid
RON:
MON:
36 36
Indirect alkylation
37 37
Alkylation and hydrogenation of isobutylene
and different butenes: octane number
comparison
Isobutylene reaction with …
Isooctane isomer RON MON
1-butene 2,2-dimethyl-hexane 72,0 77,5
1-butene 2,3-dimethyl-hexane 71,3 78,9
2-buttene 2,3,4-trimethyl-pentane 102,5 95,9
2-butene 2,3,3-trimethyl-pentane 106,0 99,4
2-butene 2,2,3-trimethyl-pentane 109,6 99,9
isobutene 2,2,4-trimethy-pentane 100,0 100,0
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
38 38
Theoretical scheme of process, using acidic
ion exchange resin catalyst
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
39 39
Oligomerisation
40 40
Oligomerisation
Gasoline blending components
- dimerisation of propene and/or butenes
Jet and diesel blending components
- oligomerisation of propene/butene/pentene
Petrochemical feedstock
- C7-C9 straight chain olefins (alcohol production)
- high purity light olefins (e.g. ethylene → 1-butene → 1-octene)
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
41 41
Feedstocks and preconditioning
Feedstocks
FCC C3-C4-C5 olefins
thermal cracking (viscosity breaking, delayed coking) light olefins
Steam reformer C3-C4-C5 olefins
Preconditioning
Hydrogen-sulphide removal: with amine scrubbing
Mercaptans removal: caustic washing
Basic materials removal (e.g. ammonia): water washing
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
42 42
Mechanism of olefin oligomerisation
Via carbenium ion intermedier, which is formed during the reaction of the olefin and strong acid.
Proposed dimerisation scheme of propene:
This intermedier is highly reactive, so it will rapidly react with an other propene molecule, forming a new carbenium ion
Proton transmission (to an other propene)
Similarly, from butene and propene-butene mixtures first C7 and C8 olefins will be formed, later C9, C12, C16 olefins.
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Strong acid
43 43
Thermodynamics of catalytic oligomerisation
Exothermic reaction (-920, -1450 kJ/kg, butene, propene
respectively)
Necessary to cool the reaction mixture
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
44 44
Catalysts for oligomerisation
Heterogeneous catalytic processes
Phosphorous acid on inert support (e.g. SiO2)
zeolite
Ion exchange resins
Homogeneous catalytic processes
Nickel and titan-coordination complex + aluminium-alkyl
Ion liquids
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
45 45
Heterogeneous catalytic processes
Temperature 150-200°C
Pressure 10-70 bar
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
46 46
Scheme of polymerisation gasoline production
(on solid catalyst)
Hűtővíz Hűtővíz
Kisnyomású
vízgőz
C3=-C4
=
alapanyag
C3=
visszavezetés
C3=
Propánmentesítő Butánmentesítő
C4=
Polimerbenzin
Kvencs
Kisnyomású
vízgőz fejlesztés
Nagynyomású
vízgőz Reaktor
Kisnyomású
vízgőz
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
Reactor
Quench
Depropanizer
Propene
recirculation
Debutanizer
C3-4 olefin
feed
Polimerysation gasoline
47 47
Catalytic polimerisation: yield and quality
Feed Value
Propene, % 21,4
Butene, % 36,3
Polymerisation gasoline
Yield, % 52,9
Specific gravity, g/cm3 0,735
RON 95,5
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
48 48
Oxygenates
49 49
Oxygenates
Alcohols
Ethers
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
50 50
Ether type gasoline blending components
MTBE ETBE TAME
Boiling point, °C 55,2 71,7 86,1
Ignition point, °C -28 -19 -11
Oxygen content, % 18,2 15,7 15,7
RON 118 118 110
MON 100 102 97
Solubility in water
comp. in water, v/v %
water in comp., v/v %
4,3
1,4
2,0
0,6
0,6
0,6
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
51 51
Isobutene containing hydrocarbon streams
Catalytic cracking (15%)
Steam cracking (45%)
Isobutane dehydrogenation (48%)
n-butene isomerisation (17%)
Fischer-Tropsch synthesis C4 fraction (12 – 20%)
( ) – izobutene content
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
52 52
MTBE synthesis
Catalyst: acidic ion exchange resin
Exothermic, reversible reaction (-37 kJ/mol)
Process parameters
methanol/isobutene mol ratio: 1,1-1,2:1
temperature: 50-90°C in main reaction area, 40-60°C in the finishing reaction area
pressure: 7-20 bar
LHSV: 4-6 h-1
CH3
C CH2
CH3
CH3
OH
CH3
C
CH3
CH3
O CH3+
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
53 53
Scheme of the conventional MTBE synthesis
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
54 54
Ether production
Jenő Hancsók: Hydrocarbon processing, BME, 15.10.2014., Copyright
55
Thank you for your attention!