KEROSENE DESULPHURIZATION BY ACID TREATMENT

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NDAGANA, GIMBA MOHAMMED M.ENG/SEET/2003/J 022

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A PROJECT SUBMITED TO THE

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DEPARTMENT OF CHEMICAL ENGINEERING,

SCHOOL OF ENGINEERING AND ENGINEERING TECHNOLOGY,

FEDERAL ,UNIVERSITY OF TECHNOLOGY, MINNA

NIGER STATE, NIGERIA

IN PARTIAL FULFILMENT OF THE REQUIREMENTS FORTHE

AWARD OF MASTER OF ENGINEERING DEGREE(M.ENG) IN

CHEMICAL ENGINEERING

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FEBRUARY, 2008

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DECLARATION

I hereby declare that this thesis is my own work anu has neither been submitted ill a

rorm for another degree nor diploma at any University or any institution.

Information derived from published or unpublished work of others · has be

acknowledged in the text.

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Ndagana, Gimba Moh'd , M.Engr.lSEET/2003/1022

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CERTIFICATION' ,

This the~is titled, KEROSENE DESVLPHURIZATION BY ACID TREATMENT

by Ndagana, Gimba Mohammed (M.EngiSEET/200311022) meets the regulations

governing the award of the degree of M.Eng of the Federal University of Technology,

inna and is approved for its contribution to scientific knowledge and literary .

resentation.

, ......... .. ...........................

ROF. K.R ONIFADE

ROJECT SUPERVISOR

R.M.OEDOGA

1EAD OF DEPARTMENT

ROF. 1.0 ODIGURE

EAN, SEEr

PROF. S.N LAMAl

DEAN, POST GRADUATE SCHOOL

..... , ............... . .................. .

EXTERNAL SUPERVISOR

. .. ......... ; ... ~r .~? .f.~d & I.,(cq

SIGNATURE AND DATE

SIGNATURE AND DATE

',': .. ..................... ..... .. ..... .... .

SIGNATURE AND DATE

SIGNATURE AND DATE

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DEDICATION

I sincerely dedicate this research work to Almighty God for hi s guidallce, protection

and graee upon my life from the very beginning to the end of this programme.

I equally dedicated the research work to my wond~rful parents Alh: Zubairu K.

Mohammad and Hajiya Hassana Zubairu, my beloved wives (Fatima and Amina Gimba) ,

twin partner, brothers, sisters and the rest family members , May God Almighty bless them

and see them through in what so ever good they are doing, Amen.

IV

ACKNOWLEDGElVlENT

My profound gl:atitude to Almighty God who has given mc the gift of Ii rc ~\Il(,1llladc

all things possible for me to actualize my dream been educated thus far. He is thc only Alfa

and Omega, the Lord of Lonls , the King of Kings, for giving mc time kll9Wledgc, wisdom,

health and guidance throughout the course of my programme. May His name be highly lifted

up for ever.

My gratitude goes to my able project supervisor Professor Onifade for his unflinching

support throughout the course of this project work. May Allah bless him ~ith his families.

My colleague, Alhaji Umar Danladi whom we rubbed minds together in seeing that \'1 ,

this work is a success.

I sincerely have to honour the unremitting effort of my parents Alhaji Zubairu and

Hajiya Hassana for their motivation, moral support and financial support, which brought me

to this cadre today. By God's grace they shall live and reap the fruit of your labour on me.

I specially appreciate the more support and encouragement of the wonderful wives

God has gave to me. Mrs. Fatima and Amina Gimba who demonstrate their love, support

and understanding to see that the dream come to reality. Also to my children Saratu , Abdul-

Hamid and Mohud Kudu who have been enduring my absence since these days.

I further appreciate the restless effort of Yusuf Mohammed a Lab Attendant 111

Chemical Engineering Department, Federal Polytechnic, Bida and Sani Mohammed, Ado

'Yakasai , Idrisu Dahiru, all in Chemical Lab Quality Control Department, Kaduna Refinery

and Petrochemical Company Ltd for their encouragement, concern and support throughout

the course or my analysi s. May God Almighty bless each and everyone or you . '

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I equally appreciate the clTort or my wonuerrul rri enus ror thei r help, encouragcmcnl.

concern anu support throughout my cuurse or stuuy. they are Engr. (Or.) Alh Dodo

Suleimanu Kouugi of Petroleum Engineering Department, Tafewa Belcwa University ,

Bauchi and Dr. Aliyu lsah Yabagi of Usman Danfodio University, Sokoto who are on thei r

Ph.D programmes. God Almighty will make the programmes a success for you alL Amin.

Finally, my appreciation goes to all those who supported me in one way or the other

to the success of this course. Thanks and may God bless.

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ABSTRACT

This work useJ Chemical Engineering Unit Operations anJ processes tt) carry out

J es ulphuri za tion of kerosene using JitTerent concentrations of tetraoxosll ,lphate (V I) aciJ

(75, 80, 85, 90 and 95 percent) at various contacting times of 10, 20, 30,40, and 50 minutes.

The amount of Sulphur removal was determined for each concentrated acid with time using

Sulphur in oil Analyzer. The result shows that the highest amount of total sulphur content

removal was achieved with 95 percent of tetraoxosulphate (VI) acid at the best contacting

time of 30 minutes.

Characteristics of treated kerosene like flash point, smoke point, specific gravity and

colour of ~ome treated samples were determined to ch~ck the consistency of treated kerosene

grade.

VII

TABLE OF CONTENTS

Title Page

Declaration

Certification

Dedication

Acknow ledgmcnt . !

Abstract

Table of Contents

List of Figur~s

List of Tablcs

List of Abbreviations

CHAPTER ONE

1.0 INTRODUTION

l.1 Background of Study

1.2 Aim and Objectivcs

'.' l.3 Relevance of Study

CHAPTER TWO

2.0 LITERATURE SURVEY

2.1 Historical Development of Kerosene

2.2 Tes t and Properties of Kerosene

2.2. 1 Flash point

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1I

III

IV

V

Vll

V III

XV

XVI

XVII

5

6

7

7

9

9

2.2.2 Fire point. 12

2.2.:; Smoke point I "" . )

2.2.4 Burning quality test 1

14

2.2.5 Sulphur content t4

2.2.6 Aniline point 15

2.2.7 Volatility 15

.2.2.8 Flammability 16

2.2.9 Colour 16

2.2.10 Calorific value 16

2.2.11 Specific gravity (Relative density) l7

2.2.12 Pour point 17

2.2.13 Viscosity 18

2.3 Types of Kerosene 18

2.3.1 Domestic kerosene 18

2.3.2 Aviation turbine kerosene (A TK) 1

19

2.3.2.1 Aviation fuel properties 19

.Volatility t9

Behaviour at a low Temperature 20

Thermal stability 22

Corrosi veness 23

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2.3.3 Dual PlllV.OSC KCroSC IlC 24

2.4 Impurtance ur Kcrosenc

2.5 Treatment o f Kerosene 26

2.5.1 Liquid sulphur dioxide extraction of aromatic 27

2.5.2 Sweetening treatment 33

2.5 .2.1 Merox sweetening · 33

2.5.2.2Mercaptan dissolving processes 34

2.5.2.3Caustic washing methods 64

2.5.3. Doctor treatment 36

2.5.3.1 Oxidising mercaptans to disulphides 38

2.5.3.2 Physical extraction processes 39

2.5.3.3 Catalytic desulphuralization 41

2.5.3.2 Sulphuric acid treatment processes 43

2.5.3.4.1 Sulphuric acid treatment conditions 44

Treatment temperature 46

Contact time 47

Acid concentration 48

Acid consumption 49

Contacting pattern 49

2.6. Detection of Mercaptans, Hydrogen Sulphide, Elemental Sulphur

Doctor Test so

2.6.1 Scope so

2.6.2 .Principle 50

2.6.3 Procedure 51

2.6.3. 1 Preliminary tes t 51 ,

2.6.3.2 Hydrogen sulphide present 51

2.6.3.3 Final test 51

2.6.4 Expression of results 52

2.7. Determination of Mercaptan Sulphur 53

2.7.1 Scope 53

2.7.2 Principles 53

2.7.3 Procedure 54

2.7.3.1 Determination of density 54

2.7.3.2 Removal of hydrogen sulfide 54

2.7.3.3 Analysis of sample 55

2.7.4 Expression of results 56

2.7.5 Calculation 57

2.8 Sulphur Compounds in Crude Oil 57 . ,

2.9 Hydrodesulphurization Processes 59

2.9.1 Chemistry of the process 62

2.9.1.1 Sulphur removal 62

2.9.1.2 Nitrogen removal 64

I 2 .. 9.1.3 Oxygen removal 6S

2.9.1.4 Ole fin saturation 66

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2.9.1.5 Metals removal 66

2.9.1,() Halides removal 07

2.10 Properties ~ll1d uses of Concentrated Tetraxosulphatc (VI) Acid ()7

2.IO.I.I'llysil'al prlljll'rlil's or l'(lllt'l'llll':Ill'd Iclr:III ,'\\lSlIlpll:111' (VI) :Icid (1/

2.10.2 Chemical properties of concentrated tetraoxosulphate (VI) acid 67

2.10.3 Uses of concentrated tetraoxosulphate '(VI) Acid 69 ·

2.11 Sulphur and its Compounds I ~"

69

2.11.1 Physical properties of sulphur 72

2.11.2 Chemical propyrties of sulphur 72

2.11.3 Uses of sulphur 73

CHAPTER THREE

3.0 EXPERIMENTAL WORK 74

3.1 Method and scope

3.2 Materials 74

3.3 Apparatus 75

3.4 Method of Removing and Determination of Total Sulphur from Raw ,

Kerosene 77

3.5 Determination of Total Sulphur in Oil 77

3.6 Characteristics of Treated Kerosene 79

3.6.1 Colour determination by the lovibond tint?mer 79

3.6.1.1 Procedure 79

3.6.2 Determination of speciric gravity 80

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3.6.2.1 'Procedure 80

3.6.3 Determillati on of smoke poillt

3.6.3 .1 Procedure 81

3.6.4. Determination of flash point 81

3.6.4. 1 Procedure 82

CHAPTER FOUR

4.0 RESULTS AND DISCUSSION 83

4.1 Tables of Results 83

4.2 Discussion of Results 90

4.2.1 Effect of acid concentration on total sulphur content of kerosene 90

4.2.2 Effect of time on total sulphur removal from kerosene 91

4 .2.3 Effect of acid concentration used on colour 92

4.2.4 Effect of acid concentration used on specific gravity 93

4.2.5 Effect of acid concentration used on smoke point 93

4 .2.6 Effect of acid concentration used on flash point 94

CHAPTER FIVE

5.0 CONCLUSIONS AND RECOMMENDATIONS 95

5.1 Conclusions 95

5.2 Recommendations 96 " , .

REFEREN CES 97

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APPENDI CES I () I I'

A: OPERATING CONDITIONS

B: rORMULAR FOR ACID PREPARATION

C: PROFILE OF MASS TOTAL SULPHUR CONTENT(wt%) WITH DIFFERENT

CONCENTRATED TETRAOXOSULPHATE (VI) ACID (%) SHOWN IN FIG. 4.1

D: PROFILE FOR PERCENTAGE TOTAL SULPHUR REMOVAL WITH

DIFFERENT CONCENTRATED TETRAOXOSULPHATE (VI) ACID (%) IS

SHOWN IN FIG. 4.2

E: RANGES FOR COLOUR DETECTION

LIST OF FIGURES

Fig2.1 Variations 111 Water Solubility 111 Kerosene (ppm weight) According to the

Temperature

Fig2.2a Liquid Sulphur Dioxide Extraction Process.

Fig2.2b Improvement of Smoke Point with Solvents (DME & DMSO)

Fig2.3 Merox Treatm,ent Process

Fig2.4 Catalytic Desulpurization Operation

Fig2.5 Sulphuric Acid Treatment (with colour sweetening)

Fig2.6 Structure of Sulphur Compound

Fig2.7 Simplified flow Diagram of the Kerosene HDS Uni t (Unibon)

Fig2.8 Structure of Sulphur Removal

Fig2.9 Structure of Nitrogen Removal

Fig2.IO Structure of Oxygen Removal

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22

30

32

35

42

45

60

63

64

65

65

Fig2.11 Structure of Oldin Saturati on

Fig3 .1 Simplifi eu Flow Diagram uf th e Kerosene DcslIlphurizatioll by

Aciu Treatment 78

Fig4.1 Prot"ile Mass ' ot" Total Sulphur Contents

tetraoxosulphate (VI) Acid

with Oi fferent Concentrated

103

Fig4.2 Profile for Percentage Total Sulphur Removal with Oiffererl t Concentrated

tetraoxosulphate (VI) Acid 104

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LIST OF TABLES

Table 2.1 Standard Physical Literature Value of Kerosene 1 0

Table 2.2 Smoke Point and Luminosity Index 28

Table 2.3 Typical Analysis of Kerosene Refining with Liquid Sulphurdioxide 3 1

Table 2.4 Extraction of Hydrogen Sulphide and Mercaptan from Naphatha using Caustic

Soda Solution

Table 2.5 Preliminary Test Procedure

Table 3.1 List of Materials (Chemicals) Used

Table 3.2 List of Apparatus/Equipment used

Table 4.1 Result of Total Sulphur Content for 10 minutes StilTing

Table 4 .2 Result of Total Sulphur Content for 20 minutes Stirring

Table 4.3 Result of Total Sulphur Content for 30 minutes Stirring

Table 4.4 Result of Total Sulphur Content for 40 minutes Stirring

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40

52

75

76

83

84

84

85

...

Table 4.5 Result of Total Sulphur Content [or 50 minutes Stirring 85

Table 4.6 SUlllmary or Total Sulphur Content ur Treated Kerosene 8(l

Table 4.7 Result of Calculated Percentage Removal of Total of Sulphur Contcnt 87

Table 4.8 Result of Colour Determination by Lovi'nbond Tinlometer 88

Table 4.9 Results of Specific Gravity Determination 89

Table 4.10 Results of Smoke Point Determination 89

Table 4.11 Results of Flash Point Determination 90

ASTM

bbl

lb

IP

of

°c

g

mm

w

%

wt%

Mg/kg

LIST OF ABBREVIATIONS

American st~ndard for testing and measurement

Barrel

pounds

Institute of Petroleum

Degree Farhenheight

Degree Centigrade

Grammes

Millimeter

Weight of sample

Percent

Weight percent

Milligramme per kilogram

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ADU

113 P

ML

Kg/cm2

DMF

DMSO

D

IS

ISO

BP

MEA

DEA

Atmospheric Distillation Unit

III i t i a I bo iii 11 g po i 11 t

Millilitre

Kilogramme per Cubic Centimeter.

Dimethyl Formamide

Dimethyl Sulforide

Drum

International Standard

International Standardization Organization

Boiling point

Methyl ethyl amine

Diethyl Amine

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