kinetics studies in synthesis of dibenzyl sulphide in liquid-liquid-solid mode akash kumar 109ch0582

43 Pages·2013·0.87 MB·English

by  Akash Kumar

KINETICS STUDIES IN SYNTHESIS OF DIBENZYL
SULPHIDE IN LIQUID-LIQUID-SOLID MODE

AKASH KUMAR
109CH0582
KINETICS STUDIES ON SYNTHESIS OF DIBENZYL SULPHIDE IN
LIQUID-LIQUID-SOLID MODE
A THESIS SUBMITTED FOR THE DEGREE OF
BACHELOR OF TECHNOLOGY
IN
CHEMICAL ENGINEEERING
by
AKASH KUMAR
109CH0582
Under the guidance of
Dr. SUJIT SEN

DEPARTMENT OF CHEMICAL ENGINEERING
NATIONAL INSTITUTE OF TECHNOLOGY
ROURKELA-769008
NATIONAL INSTITUTE OF TECHNOLOGY,
ROURKELA

CERTIFICATE

This is to certify that the thesis report titled “KINETICS STUDIES ON SYNTHESIS OF
DIBENZYL SULPHIDE IN LIQUID-LIQUID-SOLID MODE” submitted by AKASH
KUMAR having roll no. 109CH0582 is final report of the project work regarding assessment for
the prescribed curriculum of Bachelor of Technology in Chemical Engineering Session 2009-
2013 in the Department of Chemical Engineering, National Institute of Technology, Rourkela is
an authentic work to the best of my knowledge and belief.

Date: Dr. Sujit Sen
Dept. of Chemical Engineering
National Institute of Technology
Rourkela-769008

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ACKNOWLEDGEMENT

A lot of people have been involved in the making of this project to whom I would like to
thank from the bottom of my heart. Though it is not possible to acknowledge each and every
one, some people deserve a special mention.

First and foremost, I would like to thank my project guide, Prof. Sujit Sen who has been a
guide and mentor. He has been instrumental in pushing me to my limits and providing me
with research material from various sources.

I also wish to thank Prof. R. K. Singh, Head of Department and Prof. H. M. Jena for providing
me an opportunity to carry out the work and express my indebtedness towards the
Department of Chemical Engineering, NIT Rourkela. I also thank Mr. Dhruba Sakha, technical
assistant in the department of Chemical engineering, IIT Kharagpur to help us in analysis of
samples.

And at last I would like to thank all others who have supported, guided and helped me up to
this half journey of my project.

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ABSTRACT
As high quality of crude reserves are depleting and what we are left with high sulphur crude
there is a strong need for some process which can effectively and economically remove sulphur
from the process otherwise it may lead to unwanted side reactions which would entail
consumption of reactants and energy. Usually the sulphur is removed by absorption in ammonia
solution which is further processed in a Claus Unit to produce elemental sulphur which
requires a high amount of energy. With a view to making more sophisticated fine chemicals
which have higher usability and better market value, this project was undertaken to study the
kinetics of the synthesis of dibenzyl sulphide was carried out using hydrogen sulphide rich
monoethanolamine under tri phase transfer catalysis with a phase transfer catalyst (PTC). The
Amberlite IR400 has been chosen the phase transfer catalyst as it is solid and can be reused.
Parametric studies of the reaction between benzyl chloride in presence of organic solvent and
H S rich MEA were done in this work and it is tried to determine what type of conditions favor
2
the more conversion of benzyl chloride and more synthesis of dibenzyl sulphide.

V
CONTENTS
Title page ii
Certificate iii
Acknowledgement iv
Abstract v
Contents vi
List of figures viii
Chapter 1 Introduction 1-9
1.1 Hydrogen Sulfide 2
1.2 Sources of hydrogen sulphide 2
1.3 Need to remove hydrogen sulphide 3
1.4 Process used in industries to treat 3
hydrogen sulfide (removal and recovery)
1.4.1Ammonia based process 4
1.4.2 Alkanolamine based process 4
1.5 Treatment of hydrogen sulphide recoverd 6
1.5.1Claus process 6
1.5.2Crysta Sulf 7
1.5.3Wet oxidation LO-CAT process 8
1.6 Present work 8
1.7 Phase transfer catalyst 8
Chapter2 Literature survey 10-13
Chapter3 Experiments 14-19
3.1 Chemicals 15
3.2 Preparation of H S rich mono ethanol amine 15
2
3.3 Determination of sulphide content 16
3.2.1 Preparation of standard (0.1M) 16
sodium thiosulphate solution
3.2.2 Standardization of na2so4.5h2o by 16
standard kio3 solution
3.2.3 Preapration of 0.025M KIO3 solution 17
3.2.4 Estimation of sulphide concentration 17
3.4 Batch reaction 18
3.5 Analysis of organic phase 19
Chapter4 Reaction, Results and Discussion 20-25
4.1 Reaction 21
4.2 Results and DIscussion 22
4.2.1 Parametric study 22
4.2.1.1 Effect of initial sulphide conc. 22
4.2.1.2 Effect of stirring speed 23
4.2.1.3 Effect of benzyl chloride conc. 24
4.2.1.4 Recycle and reuse of Amberlite IR 400 25
4.3 Conclusion 25

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Chapter5 Summary and Conclusion 26-27
5.1 Introduction 27
5.2 summary and conclusion 27
Chapter6 Future work 28-30
6.2 Introduction 29
6.2 Investigation of mechanism and pathway 29
6.3 Other parameters affect 29
6.4 Other Aq. Phase 30
Chapter7 References 31-34

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LIST OF FIGURES:
Fig. no. fig. caption page no.

Fig 1.1 Flow Diagram of Amine Treating Process 5

Fig 1.2 Sulfur Production by the Claus Process 6
Fig 1.3 Improved Clause process 7
Fig 1.4 Amberlite IR 400 9
Fig 3.1 Kipp’s apparatus set up in lab 16
Fig 3.2 Batch reactor 18
Fig 4.1 Initial sulphide concentration effect on Benzyl chloride 22

Fig 4.2 Stirring speed effect on Benzyl chloride conversion 23

Fig 4.3 Benzyl chloride effect on Benzyl chloride conversion 24

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ABBREVIATIONS LIST
BC benzyl chloride
BM benzyl mercaptan
DBS dibenzyl sulphide
MEA monoethanolamine
GC gas chromatography
PTC phase transfer catalyst
TPC tri phase catalyst
TBAB Tetra Butyl Ammonium Bromide
CHAPTER 1
INTRODUCTION

1