This document discusses sulfonation, which is the reaction of an organic compound with sulfur trioxide to form a sulfonic acid. Sulfonation is an exothermic and rapid reaction that is difficult to control industrially. The document outlines the key components of an industrial sulfonation process, including systems for air supply, sulfur feeding, sulfur burning to generate SO3, a falling film reactor, SO3 absorption, neutralization, and effluent gas treatment. Precise control of temperature, mole ratios, and residence time are required to optimize the process and minimize byproducts.

1. BY
ANAY NILESH KACHARIA
&
GURUPRASAD VENKATAKRISHNA RAO

3. IMP NOTE
• IN SULPHONATION SO3 REACTS WITH
ORGANIC MOLECULE TO PRODUCE SULPHUR
AND CARBON BOND.
• SULFATION ON OTHER HAND IS FORMATION
OF SULPHUR-OXYGEN-CARBON BOND.

4. SULPHONATION
• SO3 is an aggressive electrophilic reagent that
rapidly reacts with any organic compound
containing an electron donor group.
• Sulfonation is a difficult reaction to perform
on an industrial scale because the reaction is
rapid and highly exothermic, releasing
approximately 380 kJ/kg SO3 (800 BTUs per
pound of SO3) reacted.

5. SULPHONATION
• Most organic compounds form a black char on
contact with pure SO3 due to the rapid
reaction and heat evolution.
• Additionally, as shown in Figure, the reactants
increase in viscosity between 15 and 300
times as they are converted from the organic
feedstock to the sulfonic acid.

6. SULPHONATION
 THIS LARGE INCREASE IN
VISCOSITY MAKES HEAT REMOVAL
DIFFICULT. THE HIGH VISCOSITY OF
THE FORMED PRODUCTS REDUCES
THE HEAT TRANSFER COEFFICIENT
FROM THE REACTION MASS.
 EFFECTIVE COOLING OF THE
REACTION MASS IS ESSENTIAL
BECAUSE HIGH TEMPERATURES
PROMOTE SIDE REACTIONS THAT
PRODUCE UNDESIRABLE BY-
PRODUCTS.
 ALSO, PRECISE CONTROL OF THE
MOLAR RATIO OF SO3 TO ORGANIC
IS ESSENTIAL BECAUSE ANY EXCESS
SO3, DUE TO ITS REACTIVE
NATURE, CONTRIBUTES TO SIDE
REACTIONS AND BY-PRODUCT
FORMATION.

8. Air supply system
• Process requires Dry and cool air .
• Air should be deficient in any kind of
disturbance
• Control valves sort out disturbance problems
• Air chiller cools the filtered air
• Regenerated air can be recycled

9. Air
supply
system

10. Sulfur feed sysytem
• Control of sulfur to sulfur burning unit is
important since that is going to effect mole
ratio in main unit
• Sulfur feed system ensures that.
• Melting of sulfur takes place here
• Entire sulfur feed system is jacketed
considering freezing point of sulphur is 112.60
C.

12. Sulfur burning unit
• Consist of atomized sulfur burning.
• Sulfur dioxide leaving burner is cooled to 4200 C
& is passed through vanadium pentoxide catalytic
converter where SO2 is converted to SO3 with 99
% efficiency.
• SO3 is initially cooled in a double pipe cooler by
regenerated air.
• Finally cooled by heat exchanger to ambient
temperature.
• Inlet mist eliminator eliminates any residual
oleum.

16. Falling Film Reactor

17. Common Types
Annular Falling Film
Multitube Falling Film Reactor
Reactor

18. • It employs interchangeable
organic metering flanges.
• The mole ratio control is
maintained on a micro scale
throughout the sulfonator.
• Cooling jackets on the reactor
remove most of the heat of the
reaction.
• The additional recycle system is
a huge benefit.
• The cooling process reduces the
amount of time of holding
sulfonic acid at elevated
temperatures.

19. • It consists of a number of vertical
tubes as arranged in a shell and
tube heat exchanger
• The tubes are generally 25mm
internal diameter and about 6m in
length.
• Generally a reactor with 70 tubes
would have a capacity of about
3 tonnes of surfactant per hour.
• The residence time from the top of
the reactor to the neutralizer is
between 2-3 minutes.

20. Features of a FFR
• Various configurations of Feedstock entry.
• Thin distribution of liquid olefin to prevent localized overheating.
• Short residence time owing to its instantaneous reaction completion.

21. Points to Remember
• Temperature gradient must be sufficent to control the extremely
vigorous intial exotherm to avoid charring.
• Air temperature should be below olefin feed.
• Film thickness has to be maintained in the order of (0.001-0.01 inches)
• Mixture of air and S03 should contain 2%-4% of S03
• Here stoichometry plays a very significant role.

22. EFFECT OF MOLE RATIOS ON 1,4 DIOXANE CONTENT

23. SO3 absorber
• Is capable of treating the total output from
the SO3 generation system to form 98%
sulfuric acid.
• It is a convenience in plant startup , shutdown
and product changeover. It is also
recommended in situations where frequent
power failures can interrupt production.
• Generally used when alcohol feedstock are
available in plant.

25. Neutralizer
• The neutralizer combines sulfonic acid or
organo-sulfuric acid with a neutralizing agent,
additives, and dilutent (water).
• A recycle loop circulates neutral slurry through
a heat exchanger to remove heat of
neutralization, mixing and pumping.
• Buffer is added to maintain pH.

27. Effluent Gas Treatment System

28. References
• Kirk & othmer , 3rd edition
• www.chemithon.com
• www.ballestra.org
• www.google.com ( Images )
• Chemistry and technology of surfactants by
Richard farn