Catalytic reforming

Axens India Private Limited

CATALYTIC REFORMING Process,Catalysts and Reactors

(Private Limited Company formed under the Companies Act, 1956)

on

Petroleum Federation of India Indian Oil Corporation Ltd. (Haldia Refinery), & Lovraj Kumar Memorial Trust

Mohan Lal Catalytic Reforming

1

Introduction

World context: High octane gasoline requirement

Catalytic Reforming

2

Introduction

World context: Low sulfur content, Low benzene content, Limited aromatics content, Limited olefins content, No lead

Catalytic Reforming

3

Introduction European Gasoline specifications trends Ultimate Severity**

2000

2005

Soon*

Sulfur, ppm max

150

50

10

5

Aromatics, vol% max

42

35

30

25

Olefins, vol% max

18

18

14

10

Benzene, vol% max

1

1

1

1

Oxygen, wt% max

-

2.7

2.7

2.7

Vapor pressure, kPa max

90

60

60

50

C5+ ethers, vol%***

15

15

15

15

Lead, ppb max

5

5

5

5

RON/MON, min

95/85

95/85

95/85

95/85

* Assumed Catalytic Reforming

** Projected final limits ≥ 2015

***banned in several states of USA 4

Introduction

Gasoline Pool specifications Bharat III Sulfur, ppm max

150

Aromatics, vol% max

42

Olefins, vol% max

21

Benzene, vol% max

1

Oxygen, wt% max

-

Vapor pressure, kPa max RON/MON, min

Catalytic Reforming

60 91/81

5

Introduction

New gasoline specifications require: ƒ Maintaining a high octane level ƒ Meeting reduced sulfur specifications ƒ Meeting reduced Aromatics and Benzene specifications

Catalytic Reforming

6

Introduction

Constraints from straight run gasoline: Initial fractionation of crude oils gives gasoline cuts with a low octane number

¾ Light gasoline (C5-C6) : RON between 60 and 70 ¾ Heavy gasoline (C7-C10) : RON between 30 and 50

Refiners have to considerably improve the quality of gasoline cuts to meet RON/MON specifications Catalytic Reforming

7

Introduction

RON/MON is increased by chemical transformation

•

Light gasoline : Isomerization process

n-paraffins Æ i-paraffins Ex: n-Hexane (RON= 24.8) Æ 2,2-DM Butane (RON= 91.8)

•

Heavy gasoline: Catalytic Reforming process n-paraffins, naphtens Æ aromatics

Ex: Cyclohexane (RON = 83) Æ Benzene (RON = 108)

Catalytic Reforming

8

Outline • •

• •

Catalytic Reforming

Fundamentals of Catalytic Reforming • Objective • Reactions – desirable and undesirable Process • Semi Regenerative Reforming • Dualforming • Continuous Catalytic Regenerative Reforming • Process Variables Reforming Catalyst • Types • Poisons Some Recent Advances in Reforming • Update on CCR Technology / Catalyst • Update on SR Technology/ Catalyst / Debottle-necking Options

9

Fundamentals

Catalytic Reforming

10

Purpose of reformer Purpose of reformer • The purpose of Reforming process is to produce : - high octane number reformate, which is a main component for motor fuel, aviation gasoline blending or aromatic rich feedstock. - hydrogen rich gas - Due to the nature of the reactions, reforming process produces also: LPG – FG – 600 psig steam with the waste heat boilers

Catalytic Reforming

11

Purpose of reformer • Reformer feed is either: - Low quality straight run naphtha - or cracked naphtha, generally mixed with straight run naphtha.

• Reformer feed pretreatment Due to the presence of contaminants in all cases and to the specific characteristics of cracked naphtha, Naphtha Pretreating unit(s) is(are) always necessary.

Catalytic Reforming

12

Chemical Reactions

Catalytic Reforming

13

Chemical reactions • Two types of reactions involved in the Octanizing process: – Desirable reactions, which lead to a higher octane number and to high purity hydrogen production. They are the reactions to promote – Adverse reactions, which lead to a decrease of octane number and a decrease in hydrogen purity. They are the reactions to minimize

Catalytic Reforming

RON

MON

• Cyclohexane

=

83

77.2

• Methylcyclohexane

=

74.8

71.1

• 1.3 dimethylcyclohexane

=

71.7

71.

• Benzene

=

114.8

> 100

• Toluene

=

120

103.5

• m-Xylene

=

117.5

115.

RON: MON:

Research Octane Number Motor Octane Number

14

Desirable reactions with hydrogen production

• Naphthenes dehydrogenation – Naphthenic compounds dehydrogenated into aromatics with production of 3 moles of H2 per mole of naphthene – Promoted by the metallic function – Highly endothermic – Thermodynamically favored by high temperature, low pressure and high number of carbons – Kinetically favored by high temperature, high number of carbon; not affected by the hydrogen partial pressure – At the selected operating conditions, reaction is very fast and almost total CH

CH

2 CH

HC 2

2

HC

CH + 3H

HC 2

CH CH

2

Cyclohe xane

Catalytic Reforming

HC

2

CH

2 CH

Benzene 15

Desirable reactions with hydrogen production • Paraffin's dehydrocyclization – Multiple step reaction – Promoted by both acidic and metallic functions

CH 2 CH 3

– Kinetically favored by high temperature, and low pressure – Dehydrogenation step becomes easier as paraffin molecular weight increases, but is competed by hydro cracking – At the selected operating conditions, much lower rate than that of dehydrogenation Catalytic Reforming

CH 2

CH 2

CH 2

CH 2

CH 2

CH

CH 3

CH 3

CH

CH 2

CH 2

CH 2

CH 3

CH 2 CH

2

C H 7 14

C H 7 16

CH

+H

CH 3

CH 2

CH 2 CH 2

CH H C 2

CH 3

CH 3 CH 2

CH 2

Methylcyclohexane CH 2

CH 2

CH CH

H C 2 CH 2

CH 2

CH C

CH 3

HC

CH + 3H 2 3 CH

CH

16

Desirable reactions with hydrogen production

• Linear paraffin's isomerization – – – –

Promoted by the acidic function Slightly exothermic Fast Thermodynamically dependant on temperature; pressure has no effect – Kinetically favored by high temperature; not affected by the hydrogen partial pressure

C H 7 16

Catalytic Reforming

C H 7 16

Carbon atom

C4

C5

C6

C7

C8

% Isoparaffin at 500°C

44

58

72

80

88 17

Desirable reactions with hydrogen production

• Naphthenes isomerization – Desirable reaction because of the subsequent dehydrogenation of the alkylcyclohexane into an aromatic – Difficulty of ring rearrangement and high risk of ring opening (paraffin formation) – At the selected operating conditions, theoretically low rate but subsequent dehydrogenation shifts the reaction towards the desired direction – Slightly endothermic – Easier reaction for higher carbon number

Catalytic Reforming

RON

MON

•

Ethylcyclopentane

=

67.2

61.2

•

Methylcyclohexane

=

74.8

71.1

•

Toluene

=

120

103.5

18

Adverse reactions (m)

• Hydrocraking

+H 2

– Hydrocracking affects either paraffins or olefins

C H 7 16

– Promoted by both acidic and metallic functions – Favored by high temperature and high pressure – Exothermic (risk of runaway reactions) – At the selected operating conditions, hydro cracking reaction could be complete, but is limited by kinetics

C H 7 14

Catalytic Reforming

C H 7 14 (a) +

+H 2 C H 4 8

C H 3 8

(m) +H 2 C H 4 8

C H 4 10

19

Adverse reactions

• Consequences of cracking: – Decrease of paraffins and increase of aromatics proportion (i.e. increase in octane) in the reformate and a loss of reformate yield – Decrease in hydrogen production (cracking reactions consume hydrogen) – Increase of light ends production and low molecular weight paraffins

Catalytic Reforming

20

Adverse reactions

• Hydrogenolysis – Promoted by metallic function – Favored by high temperature and high pressure – Exothermic (risk of runaway reactions) +H C H 7 16

2

CH + 4 C H 6 14

or

+H C H 7 16

Catalytic Reforming

2

C H+ 2 6 C H 5 12

21

Adverse reactions • Hydrodealkylation – – – – –

Breakage of the branched radical of an aromatic ring Promoted by metallic function Favored by high temperature and high pressure Consumes hydrogen and produces methane But at the selected operating conditions, and with the selected catalyst, this reaction is not significant +H

+ CH 2

Xylene

4

Toluene

+ CH

+H

4

2

Toluene

Catalytic Reforming

Benzene

22

Adverse reactions • Alkylation – Addition of an olefin molecule on an aromatic ring – Promoted by metallic function

– leads to heavier molecules which may increase the end point of the product – High tendency to form coke; must be avoided CH + CH2= CH – CH3 Benzene

Catalytic Reforming

Propylene

3

HC

Isopropylbenzene

CH 3

23

Adverse reactions • Transalkylation (alkyl disproportionation) – – – –

Dismutation of 2 toluene rings to produce benzene and xylene Promoted by metallic function Favored by very severe conditions of temperature and pressure At the selected operating conditions, and with the selected catalyst, this reaction is negligible

+

+

Toluene

Catalytic Reforming

Toluene

Benzene

Xylene

24

Adverse reactions • Coking – Results from a complex group of reactions. Detailed mechanism not fully known yet – Linked to heavy unsaturated products (polynuclear aromatics) and heavy olefins traces or diolefins present in the feed or in CCR reactions – Coke deposit reduces active contact area and reduces catalyst activity – Favored by low pressure

In Octanizing operating conditions, necessity of a continuous regeneration to maintain a low level of coke Catalytic Reforming

25

Chemical reactions – All these reactions occur in series and parallel to each other producing a complicated reaction scheme. In an effort to simplify the scheme according to the reaction rates the main reactions take place in the following order:

Catalytic Reforming

• 1st reactor

Dehydrogenation Isomerization

• 2nd and 3rd reactors

Dehydrogenation Isomerization Cracking Dehydrocyclization

• 4th reactor

Cracking Dehydrocyclization

26

Catalyst Distribution

• •

Highly endothermic transformation Reaction rates vary widely

The overall amount of catalyst needed for the transformation is distributed – not equally – among several adiabatic reactors in series with intermediary heaters providing the required heat energy input

Catalytic Reforming

27

Temperatures and Compositions inside Reactors H1

R1

H2

R2

H3

R3

Reactor Temperature, °C T0 T0 - 25 T0 - 50 Composition, Vol% P0 = 60 N0 = 30 A0 = 10 R1 Catalytic Reforming

Aromatics Paraffi ns Naphthenes

R2 R3 Position in Reactor

28

Chemical reactions – The catalyst distribution is:

• • • •

R1 R2 R3 R4

= = = =

10% 15% 25% 50% HEAT OF REACTION (1) KCAL/MOLE

RELATIVE RATE (2) APPROX.

Naphthenes dehydrogenation

- 50

30

Paraffin dehydrocyclization

- 60

1 (base)

Isomerization: Paraffins

+2

REACTIONS

Naphthenes Cracking

+ 10

(1) (2)

Catalytic Reforming

+4

3 0.5

Heat of reaction < 0 = endothermic reaction. For pressure below 15 kg/cm2.

29

Reforming Processes

Catalytic Reforming

30

Fixed bed reformer

• •

The most frequent type of unit Current licensors • Axens, UOP • In the old days (Chevron, Amoco, Exxon, Engelhard) Interheater 1 Interheater 2 B 1

2

3 A

Separator

Feed Recycle Compressor

Fuel Gas LPG Stabilized Reformate

C Catalytic Reforming

31

Conventional Unit

Booster Compressor

HydrogenRich Gas

Separator

1

2

3

Recontacting Drum

Unstabilized Reformate

Feed Recycle Compressor

Catalytic Reforming

32

Dualforming Texicap™+ RG682

1

Feed

2

3

Booster Compressor R e g e n C 2

C C R R X

12b

Hydrogen Rich Gas

Recontacting Drum

Packinox Recycle Compressor

Unstabilized Reformate

• Last Reactor Catalyst Continuously Regenerated • Provides excellent option for the revamp of existing SR reformers Catalytic Reforming

33

Continuous Catalytic Regenerative Reforming

Catalytic Reforming

34

Continuous Catalytic Regenerative Reforming Upper Surge Drum Lock Hopper

Elutriator Upper Hoppers

LC

LC LC

Reduction Chamber

Reactors

LC

Coke R1

FC

H2

R2

FC

H2

R3

FC

H2

Regenerator

R4

FC

N2

N2

Lower Hopper Lift Pot

FC

• Catalyst Continuously Regenerated • With advanced catalysts longer catalyst life and less makeup rates possible Catalytic Reforming

35

Objectives of Regeneration Section Recover initial catalyst activity

•

Coke removal

2 Burning zones

• Metal redistribution & chloride adjustment

Oxychlorination

•

Calcination

Catalyst drying

Each zone independently optimized Catalytic Reforming

36

RegenC

Spent C atalyst C om bustion G as from D ry Loop Additional Air

Chloriding Agent + water

O xychlorination C alcination G as

Burning with dry gas control: % O 2 , tem perature

Prim ary Burn

Finishing Burn

T o D ry Burn Loop

O xychlorination

T o Effluent T reatm ent

C alcination

Catalyst’s specific area is m aintained

O xychlorination control: % O 2 , tem perature and m oisture O ptim um Pt dispersion

R egen erated C atalyst Catalytic Reforming

37

RegenC Catalyst Regenerator «Coked» Catalyst Com bustion Gas Inlet

Primary Burning Air Inlet

Finishing Burning Combustion Gas Outlet Oxychlorination Outlet

Oxychlorination Chloriding Agent Inlet

Calcination Calcination Gas Inlet

Catalytic Reforming

Regenerated Catalyst 38

Processes Variables

Catalytic Reforming

39

• Pressure • Temperature • Space velocity • Hydrogen partial pressure (H2/HC) • Quality of the feed • Operating Parameters Summary

Catalytic Reforming

40

Process variables

• Each of them can be fixed by the operator - within the operating range of the equipment independently from the others

• For one set of independent variables, for same feed characteristics, there is only one performance of the unit i.e. one set of values for: – Product yields – Product quality (Octane) – Catalyst stability (coke make) Catalytic Reforming

41

Pressure

Catalytic Reforming

42

Pressure

• Pressure is the basic variable because of its inherent effect on reaction rates

• Effect of pressure on reactions – Low pressures enhance hydrogen producing reactions: dehydrogenation, dehydrocyclisation, coking – Cracking rate is reduced The lower the pressure, the higher the yields of reformate and hydrogen for a given octane number. But high coking rate (compensated by continuous regeneration)

Catalytic Reforming

43

Pressure

• Average catalyst pressure used, close to last reactor inlet pressure

• During transient conditions (start up, shutdown, upsets) it is recommended to increase the pressure to lower coke formation

• Limits of operators action – Pressure rise limited by equipments design pressure – Pressure lowering limited by recycle compressor design power and intake volume Catalytic Reforming

44

Temperature

Catalytic Reforming

45

Temperature • Most important and most used operating parameter with space velocity

• Catalyst activity is directly related to reactor temperature. By

simply raising or lowering reactor inlet temperatures, operators can raise or lower product quality and yields

• It is commonly accepted to consider the weight average inlet temperature (WAIT)

WAIT =

(wt of catalyst R1 x Ti1) + (wt Catalyst R 2 ) x Ti2.... + (wt Catalyst R4 ) x Ti4 Total wt of catalyst Where

Catalytic Reforming

Ti1, Ti2, … are inlet temperature of reactors (wt of catalyst R1)… are weight of catalyst in reactors

46

Temperature • An increase of temperature (i.e. WAIT) has the following effects: – – – –

Increases octane Decreases the yield (of C5+ fraction) Decreases the H2 purity. Increases the coke deposit

• A slight increase of temperature (WAIT) through the life of the catalyst makes up for this activity loss

• Larger and temporary changes in temperature are required: – To change octane - at constant feed quality and quantity – To change feed quantity and still maintain octane – To change feed quality and still maintain octane Catalytic Reforming

47

Space Velocity

Catalytic Reforming

48

Space velocity • Weight hourly space velocity: WHSV = Weight of feed (per hour) Weight of catalyst in reactors • Liquid hourly space velocity:

LHSV =

Volume of feed at 15°C (per hour) Volume of catalyst in reactors

• Linked to residence time of feed in the reactor and affects the kinetics of the Reforming reactions

Space velocity

Catalytic Reforming

residence time

higher severity

Octane increased Lower reformate yield Higher coke deposit

49

Space velocity • Operators must bear in mind that each time liquid feed rate is changed, a temperature correction must be applied if octane is to be maintained.

• Important recommendation – Always decrease reactor inlet temperature first and decrease feed flowrate afterwards – Always increase feed flowrate first and increase reactor inlet temperature afterwards

Catalytic Reforming

50

Hydrogen to hydrocarbon ratio

Catalytic Reforming

51

Hydrogen to hydrocarbon ratio • H2/HC ratio: Where

H2 Pure hydrogen (mole/hour ) in recycle = HC Naphtha flow rate (mole/hour )

R

is the recycle flow in Kg/h (or lb/h)

M F m Y

is the recycle gas molecular weight is the feed rate in Kg/h (or lb/h) is the feed molecular weight vol. fraction of H2 in the recycle gas

=

H2

R HC =

M xY F m

• The recycle gas MW is obtained by chromatographic analysis, as well as the H2 vol. fraction (Y)

• The feed MW is obtained by chromatographic analysis or by correlation from its distillation range and specific gravity Catalytic Reforming

52

Hydrogen to hydrocarbon ratio • Operators can change the H2/HC ratio by lowering or increasing the recycle compressor flow

• For a given unit, the amount of recycle is limited by the recycle compressor characteristics (power, suction flow)

• The H2/HC ratio has no obvious impact on the product quality or yield

• But a high H2/HC ratio reduces the coke build up • It is strictly recommended to operate with a H2/HC ratio equal to (or higher than) the design figure

Catalytic Reforming

53

Feed quality

Catalytic Reforming

54

Feed quality Chemical composition

• Characterization of the feedstocks by: • With a higher 0.85 N + A

0.85 N + A

– The same Octane content will be obtained at a lower severity (temperature) and the product yield will be higher – Or for the same severity (temperature), the Octane content will be higher – Higher naphtenic content. The endothermic reaction heat is increased and the feed flow rate will be limited by the heater design duty

• With lower 0.85 N + A

– Higher paraffin content. The hydrogen purity of the recycle gas decreases and operation will be limited by the recycle compressor capacity

• Impurities

– Temporary or permanent reduction of catalyst activity by poisons contained in the feed

Catalytic Reforming

55

Feed quality Distillation range

• The feed distillation range is generally as follows: • IBP (Initial Boiling Point) 70-100 °C 150-180 °C • EP (End Boiling Point)

• Light fractions: Cyclization of C6 more difficult than that of C7-C8 The lighter the feed, the higher the required severity for a given Octane • Heavy fractions: high naphthenic and aromatics content Lower severity to obtain good yields But polycyclic compounds which favor coke deposit EP higher than 180°C are generally not recommended Catalytic Reforming

56

Operating Parameters Summary

• Hereafter the theoretical effect on the unit performance of each independent process variable taken separately: Increased

RONC

Reformate yield

Coke deposit

Pressure Temperature Space velocity

H2/HC ratio

A + 0.85 N Naphtha Quality

End boiling point Initial boiling point

Catalytic Reforming

57

Catalysts

Catalytic Reforming

58

Catalyst The main characteristics of a catalyst other than its physical and mechanical properties are : • The activity o catalyst ability to increase the rate of desired reactions o Is measured in terms of temperature • The selectivity o Catalyst ability to favor desirable reactions o Practically measured by the C5+ Reformate and Hydrogen yields • The stability o Change of catalyst performance ( activity, selectivity )with time o Caused chiefly by coke deposit and by traces of metals in feed o Measured by the amount of feed treated per unit weight of catalyst. C5+ wt reformate yield is also an indirect measure of the stability. Catalytic Reforming

59

Catalyst

•

Catalyst • Chlorinated gamma alumina with nanao particle of Pt • The chlorinated gamma alumina has too strong acid sites • The Pt promotes hydrogenolysis of Pt + H2

Catalytic Reforming

60

Catalyst

•

In the 90’s Procatalyse (now Axens) launched promoted Pt/Re catalyst • RG 582 • Then RG 682 in 2000

•

The promoter provides two benefits • Reduced hydrogenolysis by a modification of the metallic cluster • Lower the number of the strongest acid sites

Catalytic Reforming

61

Catalyst

•

The stability of Pt has been improved by addition of promoters (Re, Ir)

•

The hydrogenolysis of Pt has been reduced by addition of promoters

•

The acidity of the chlorinated gamma alumina has been tuned by addition of promoters

Catalytic Reforming

62

Catalyst •

To improve the catalyst stability the Pt sintering has to be hindered Addition of promoters

•

• Rhenium or Iridium

•

Explanation • Re and Ir is alloyed with Pt Î the “boiling point” of Pt is increased Î Sintering reduced

1.00

0.75 Pt accessible Pt Total 0.50

•

Operating conditions • T = 650°C • H2 = 2 000 L/kg/h

Pt + Re Pt

0.25 0

Catalytic Reforming

10

20 30 40 50 Time, hours

63

Catalyst •

Reforming catalysts are bimetallic catalyst consisting of platinum plus promoters on an alumina support, Rhenium and Tin being essentially one of the promoter besides the others.

•

The main features of these catalysts are : o High purity alumina support - High mechanical resistance o Platinum associated with Rhenium - high stability & selectivity o Platinum associated with Tin – high selectivity o High Regenerability

•

The combination of these qualities give the following advantages: o High Reformate yield o High hydrogen yield o High on - stream factor o Low catalyst inventory

Catalytic Reforming

64

Catalyst ¾Platinum (Pt) plus other promoter(s) impregnated on to gamma alumina containing around 1% wt chloride to provide acidity. ¾Since 1967, bimetallic catalysts have been widely used. ¾The second metal comes from the group ŽRhenium (Re) ŽTin (Sn) ŽIridium (Ir) ŽGermanium (Ge)

Catalytic Reforming

65

WHICH METAL COMBINATION TO CHOOSE

¾Depends on what you want from the catalyst - "THE OBJECTIVES" ¾Stability / cycle life ¾Selectivity towards Žhydrogen (H2) Žliquid reformate (C5+ reformate) Žbenzene yield in C5+ reformate

Catalytic Reforming

66

Stability • Normal causes for catalyst ageing/deactivation – metal sintering – temperature – metallic phase – presence of chloride – deposition of coke on metal and acid sites Coking effect can be split – 1. Degree of poisoning of deposited coke – 2. Relative coking rate Catalytic Reforming

67

SELECTIVITY • Desired yields are:

• Benzene

– – –

hydrogen C5+ reformate low benzene

– yield can be minimised by pre-fractionating the precursors (MCP, CH, nC6P) which are present in the fraction boiling between 70 to 85°C – benzene is also produced by the hydrodealkylation of alkyl benzenes

• Loss of desired yields is caused by cracking – hydrocracking involving the metal plus acid sites – hydrogenolysis involving the metal in the presence of hydrogen Catalytic Reforming

68

SUMMARY - EFFECT OF SECOND METAL

• Tin and Germanium – increases selectivity towards desired products – no stability benefit

• Rhenium and Iridium – increase stability – no major effect on yield selectivity

• Other effects such as regenerability and tolerance to feedstock

impurities has led to the PtRe combination being preferred catalyst

Catalytic Reforming

69

TRI METALLIC CATALYST

• RG 582 introduced 1994 • Third metal moderates hydrogenolysis activity to • •

Catalytic Reforming

between that of balanced PtRe and PtSn Desired yields increased – Hydrogen by 0.1 to 0.15wt% – C5+ by around 1 wt% Stability studies in pilot plant show 93 - 100% of balanced bimetallic catalyst, but in commercial units >100% is commonly seen.

70

Pilot test results Low pressure pilot test

Axens New series - Multi Promoted Catalyst - Reduced Pt content

Selectivity C5+ yield

Previous Generation - Bi-promoted catalyst - High Pt content - Tri-promoted catalyst - Reduced Pt content

Stability (time)

Selectivity & stability improvement Catalytic Reforming

71

Catalysis Mechanism •

The catalyst affects reaction rates through its two different functions/type of sites: o Metallic, and o Acidic

Different types of reactions are promoted by these sites as: o o o o o

Catalytic Reforming

Dehydrogenation Dehydrocyclisation Isomerisation Hydrogenolysis Hydrocracking

Metallic Metallic + Acidic Metallic + Acidic Metallic Metallic + Acidic

72

Catalysts Poisons

Catalytic Reforming

73

Catalyst Contaminants Temporary poisons •

Which can be removed and the proper Activity and Selectivity of catalyst is restored.

•

The most common temporary poisons ( inhibitors ) are: o o o o o

Catalytic Reforming

Sulphur Organic nitrogen Water Oxygenated organics Halogens

74

Catalyst Contaminants (Contd…) Permanent poisons –

Which induce a loss of activity which can not be restored. Main permanent poisons are • • • • • • • • •

Catalytic Reforming

Arsenic Lead Copper Iron Nickel Chromium Mercury Sodium Potassium

75

Reactor Types

Catalytic Reforming

76

Typical Axial Fixed-Bed Reactors

Catalytic Reforming

77

Typical Radial Fixed-Bed Reactor Bolted metal shroud and cover

Catalyst Dead Space

The design of the upper part of the reactor was made to take into account - density change (settling) - possible by-passing of catalyst - space for mechanical assembly

Catalytic Reforming

78

Typical Radial CCR Reactor Feed

Catalyst

Effluent Catalytic Reforming

79

Texicap TM

A New Concept of Radial Reactor Internals A Flexible Flow-guide that molds to the shape of the top of the bed

Catalytic Reforming

80

Typical Radial Fixed-Bed Reactors BEFORE Bolted metal shroud and cover

Catalyst Dead Space

The design of the upper part of the reactor was made to take into account - density change (settling) - possible by-passing of catalyst - space for mechanical assembly

Catalytic Reforming

81

Modifying Radial Fixed-Bed Reactors with Texicap Catalyst Dead Space

BEFORE

AFTER

Gained with Texicap

Catalytic Reforming

82

Catalyst Sampler

Refilling Sampling Box

Draining N2

ATM FL

Handling Head

Receiving Pot Drain Catalytic Reforming

83

Catalytic Reforming

84