This document provides an overview of conventional and alternative technologies for producing ultra-low sulfur fuels. It discusses the needs for desulfurization due to sulfur compounds being poisonous in fuels and harmful for vehicles and engines. It then summarizes five main desulfurization technologies: oxidative desulfurization (ODS), bio desulfurization (BDS), hydro desulfurization (HDS), adsorptive desulfurization (ADS), and extractive desulfurization (EDS). ODS and BDS are explained in more detail, including oxidants, catalysts, reaction mechanisms, pathways, and specific microbial strains used in BDS. Recent global sulfur limits in diesel are also mapped.

1. An Overview of
Conventional and
alternative
technology for
production of Ultra-
low Sulfur fuels Presented by:
ER.Rahul
Chemical Engineer

2. Jens
Martensson
 Introduction
 Needs of Desulfurization
 Technologies
 ODS (Table and figures)
-Oxidants,
-catalysts,
-Mechanisms.
 BDS (Table and figures)
-Introduction,
-pathways,
-peeps.
 Conclusion.
Contents
2

3. Jens
Martensson
• Hydro carbon fuels derived from fossils fuels. It is used for generation of electricity
and transportation vehicles also.
• Approximately 96% transportation vehicles on field.
• Nitrogen and sulfur compounds harmful contents in fuels.
• Some of the polluted compounds are mercaptans, sulfides, disulfides, & thiophenes.
• Due to the safe environment conditions and maintenance vehicles efficiency. So,
Sulfur compounds stickly remove from petrol, diesel, jet fuels.
• 10 -15 ppm Sulfur is good.
Introduction
3

4. Jens
Martensson
• Sulfur compounds are poisonous for transportation vehicles, during the time of
combustion.
• Sulfur compounds are also responsible for corrosion of the combustion engine and
deactivation of the catalyst present in the catalytic converter.
• Some countries initiated on production of Ultra low Sulfur fuels.
• As, the production rate strongly worked on Sulfur compounds is:
Needs of Desulfurization
4
500 to 15 ppm
300 to 30 ppm
10 ppm
350 to 50 ppm
150 to 50 ppm
}
}
USEPA
(United states Environmental
protection Agency)
India
(some major cities)
Europe (Germany)

5. Jens
Martensson
5
Table 1: Sulfur specification on diesel and gasoline in some part countries and their year wise
implementation.
1: Sulfur content in
gasoline.
2: Sulfur content in diesel.
1
2
1
2
1
2
1
2
1
2
1
2
1
2
1
2
1
2
1

6. Jens
Martensson
Technologi
es
ODS (Oxidative Desulfurization)
BDS (Bio Desulfurization)
HDS (Hydro Desulfurization)
ADS (Adsorptive Desulfurization)
EDS (Extractive Desulfurization)
6

7. Jens
Martensson
Oxidative Desulfurization
• It is alternative conventional
technology for production of low
sulfur.
• It completely work by oxidant to
remove sulfoxides and sulfones.
• It is better than HDS process.
• ODS process possesses a reaction
mechanism that enhances the
polarity of sulfur compounds and
enables easier separation from the
fuel.
7
Oxidation of DBT into corresponding
Sulfone
Figure
1

8. Jens
Martensson
Oxidants
Different types of Oxidants which
is useful for the preparation of low
sulfur in liquid fuels
• Hydrogen peroxide
• Organic Hydroperoxide
• Potassium ferrate
• Fenton’s reagent
• Nitric acid
• Nitrogen dioxide.
8

9. Jens
Martensson
9
Catalyst
• In ODS process both Heterogenous and Homogenous catalyst used.
• A heterogeneous catalyst has attracted more attention compared to the homogeneous
catalyst.
• Catalyst is used on behalf of activation and stability conditions on working BDS process.
• The active phase of catalysts is primarily constituted of transition metals viz,
molybdenum, iridium, palladium, nickel, platinum, tungsten, and rhodium.
• Mo-based catalyst was modified with bismuth to increase the catalytic activity of
desulfurization of light cycle oil.
• Mesoporous material is best choice for preparation of catalyst. It is in demands also.
• MCM-41 and SBA-15 exhibit a high surface area, good thermal stability, narrow and
controllable pore size, and offers several other benefits.
• The performance of the catalytic ODS using the Mo-supported 4A molecular sieve as a
catalyst and cyclohexanone peroxide (CYHPO) as an oil-soluble oxidizing agent for the
removal of BT and DBT was investigated.

10. Figure 2:Typical oxidation reaction scheme of DBTs in the
presence of
𝑀𝑜𝑂3/𝐴𝑙2𝑂3
Oxidative reaction mechanism
and reactivity

11. Jens
Martensson
• It is environmental friendly technique.
Also, it is low cost process.
• In this method, micro-organisms
either bio-transform sulfur
compounds or utilize sulfur-
containing compounds as a sole
source for growing purposes under
ambient pressure and temperature.
• It have different pathways for the
metabolism of DBT.
• The destruction of one bond or a
fragment of DBT by enzymatic action.
• See figure 3.
BDS (Bio Desulfurization)
11
Figure 3: Kodama metabolic
pathway for desulfurization of
DBT.

12. Jens
Martensson
12
Specific Oxidative
pathways
• The carbon skeleton of the DBT remains intact,
which results into no loss of calorific value of the
fuel.
• In the first step, DBT is oxidized to DBTO, further
converted into 𝐷𝐵𝑇𝑂2.
• This metabolic route requires four enzymes for
the transformation of DBT into 2-
hydroxybiphenyl.
• Some enzymes also included for further process.
Like DszA to FMNH2, O2.
• The conversion of the sulfone to a sulfinate
(HPBS) is catalyzed by DszA.
• The fourth enzyme is an aromatic sulfinic acid
hydrolase, i.e., required to complete the reaction.
• Then, further led mechanism occurs between all
required reaction for process.

13. Jens
Martensson
• Aqueous, oil, cellular is main components given by BDS system.
• Cells in aggregates in the aqueous phase.
• it is a two-phase system in which the oil phase interacts with whole cells (biocatalyst)
in the aqueous phase.
• The BDS of liquid fuels is usually accompanied by employing the entire cell as a
biocatalyst, which facilitates the industrialization of BDS.
• As a Biocatalyst used in desulfurizing micro-organisms in the BDS process such as
Rhodococcus, Rhodococcus erythropolis, Mycobacterium, Pseudomonas delafieldii,
Bacillus subtilis WU-S28, R. erythropolis SHT87, Myco- bacterium pheli WU-F1,
Lysinibacillus sphaericus, Desulfobacterium indolicum.
• BDS process as utilized 4S metabolic route to degrade DBT, which help in increasing
the contact between the cell and the organosulfur compounds, and eventually
increases Sulfur removal.
BDS Peep
13

14. Jens
Martensson
• Researchers have made an attempt to examine the abilities of microbial strain in the
real liquid fuel system.
• The desulfurization of DBT by two different bacteria, namely, Rhodococcus sp. and
Arthrobacter sulfure us, isolated from oil-contaminated soil/sludge samples.
• The desulfurization ability of Gordonia sp. IITR100 for the BDS of heavy crude oil and
hydro-desulfurized oil.
• This microorganism was able to reduce 98% and 70% sulfur from two different diesel
oils.
• Viscosity of this heavy crude oil was also decreased by 31%.
Continue - BDS Peep
14

15. Jens
Martensson
15
Table 2: BDS of Organosulfur compounds under optimum reaction
conditions.

16. Jens
Martensson
16
Recent Implementation Map over
Desulfurization- Year 2020
o Afghanistan - 50 ppm
o Indonesia - 50 ppm
o India - 10 ppm
o Sri-Lanka - 500 ppm
o New Zealand - 10 ppm
o Bosnia and Herzegovina - 10 ppm
o Finland -10 ppm
o France - 10 ppm
o Germany - 10 ppm
o Liechtenstein - 10 ppm
o Malta - 10 ppm
o Norway -10 ppm
o Portugal - 10 ppm
o Sweden - 10 ppm Figure 5: World map shown
Sulfur level in Diesel

17. Jens
Martensson
• The production of liquid fuels increases in demand globally. Under the Environmental protection
act.
• The high Sulfur content in liquid fuels strictly prohibited. It will continue to work on decreasing the
rate of Sulfur from fuels. It might immensely pressure on refineries.
• The ODS process is very useful as compared to HDS and BDS.
• In talking about the ADS process also the best respective method for producing the ultra low-
Sulfur fuel because it is convert from 300 to 10ppm.
Conclusion
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18. Jens
Martensson
• Journals – Review in Chemical Engineering.
• Le Bui TT, Van Ho S, Nguyen BT, Uong HT. Synthesis, characterization and application
of some non-halogen ionic liquids as green solvents for deep desulfurization of
diesel oil.
• McFarland BL. Biodesulfurization. Curr Opin Microbiol 1999.
• Otsuki S, Nonaka T, Takashima N, Qian W, Ishihara A, Imai T, Kabe T. Oxidative
desulfurization of light gas oil and vacuum gas oil by oxidation and solvent
extraction. Energy Fuels 2000.
• Sarda KK, Bhandari A, Pant KK, Jain S. Deep desulfurization of diesel fuel by selective
adsorption over Ni/Al2O3 and Ni/ZSM-5 extrudates.
• Jiang, Zongxuan, Lü, Hongying, Zhang, Yongna, Li, Can,Cuihua Xuebao/Chinese
Journal of Catalysis, Oxidative desulfurization of fuel oils.
References
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19. Thank
You