Detailed Report on the Role of Surfactants in Laundry Detergents

This report provides a comprehensive overview of the role of surfactants in laundry detergents. It begins by defining surfactants as surface-active agents with hydrophobic tails and hydrophilic heads, essential for trapping and removing dirt. The report details four main types of surfactants: anionic, cationic, non-ionic, and amphoteric, explaining their chemical properties and specific functions in detergents. Anionic surfactants excel at removing clay, dirt, and oil stains due to their negative charge, while cationic surfactants, with a positive charge, are used in fabric softeners and possess anti-static properties. Non-ionic surfactants are neutral and effective at removing oil stains, and amphoteric surfactants have dual charges, behaving differently in acidic and alkaline solutions. The report further explains how these surfactants work in laundry detergents to suspend dirt in water, prevent redeposition, and reduce surface tension, ultimately improving the cleaning process. It concludes that surfactants are vital components in detergents, enabling the removal of various types of stains and contributing to effective cleaning.

Role of Surfactants in
Laundry
DETERGENTS
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Table of Contents
INTRODUCTION...........................................................................................................................3
Role of surfactants in laundry detergents.....................................................................................3
CONCLUSION................................................................................................................................6
REFERENCES.............................................................................................................................7
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INTRODUCTION
Surfactants are primary ingredient of detergents which are used for cleaning different
dirty surfaces. The term surfactant refers to surface active agent that is utilized to trap the dirt
from the surface and remove it completely. Surfactants mainly has two parts which contains one
hydrophobic tail and one hydrophilic head. The hydrophobic tail mainly surrounds the soil part
and hydrophilic head is responsible for surrounding water (Vento and et. al., 2019). This blog
explains the role of surfactants in detergents and the different type of surfactants detergent
possess.
Role of surfactants in laundry detergents
Definition of surfactants
These are compounds which reduces the surface tension between two liquids and are
commonly are organic compounds which are amphiphilic which states that they contain both
hydrophobic and hydrophilic substances. These surfactants could be anionic, nonionic, cationic
and amphoteric (Landeck, Baden and John, 2020). Surfactants are most commonly used
ingredient in detergents, cleaning materials, cosmetics and other personal care goods.
Type of surfactants
The main four classification of surfactants are described below in detail:
Anionic surfactants:
These surfactants are very good in removing clay, dirt and oil stains. They are classified
as negatively charged hydrophilic polar surfactants. When this surfactant is dissolved in water
than it gets ionized and possess negative charge. The negative charge of these surfactants get
bind with positive charge of dirt or clay and helps in successful removing of these stains. Various
of anionic surfactant includes alkylbenzene sulfonates, alcohol sulfates, sulphonic acid and
carboxylic acid. Detergent containing these surfactant molecules is a type of synthetic detergents
which contains lipophilic hydrocarbon group. The detergent molecule is made up of long
hydrocarbon chain and negative ionic material which is water soluble (Abney and et. al., 2021).
These detergent are sodium salts which is made up of long chain of sulphonate alcohol or
hydrocarbon. There are different types of anionic surfactants, some of which are defined below:
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 Alkylbenzene sulfonates (ABS): This is the most commonly utilised surfactant
and they could be branched such as tetrapropylenebenzene sulfonate or linear
such as linear alkylbenzene sulfonate. These are classified as organic chemical
compounds which are considered as hard detergents as they are resistant to
biological degradation.
Cationic surfactants:
These type of surfactants on their hydrophilic end possess a positive charge which makes
them useful in anti-static goods such as fabric softeners. They have an excellent fat dissolving
properties and in fabric softeners these are utilized as an anti-static agent as well as finishing
agents. Some of the cationic surfactants possess biocidal properties which are utilized in
detergents for disinfections. These surfactants are composed of polar and non-polar which are
made of several alkyl groups. The main work of cationic surfactant is to reduce the surface
tension between water and dirt in order to make them suitable for removing stains. These
surfactants increase the action of anionic surfactants. Cationic surfactants are also used in hard
water and acidic environment but they possess very weak power of cleaning. Some example of
cationic surfactants includes dimethyl distearyl ammonium chloride. There are different types of
cationic surfactants out of which one has been explained:
 Dimethyl distearyl ammonium chloride: it is also known as
Dimethyldioctadecylammonium chloride which is one of the organic compound
and is categorised as quaternary ammonium salt. The molecule contains nitrogen
center which is made up of two methyl groups and two stearyl group (Boza
Troncoso and Acosta, 2019). This molecule contain surfactant like properties
because it is composed of cationic ammonium and long chain of hydrocarbon
groups.
Non-ionic surfactants:
These surfactants are neutral which means that they do not possess any charge on their
hydrophilic end. These are categorised as better surfactants molecules than anionic surfactants as
they remove oil stains. These contains wide number of synthetic chemicals of various types and
shapes. These surfactants join uncharged hydrophilic and hydrophobic molecule together which
makes them effectual in spreading as well as wetting agents. The hydrophilic element of these
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surfactants is based on polyethylene oxide which is a petroleum derived. These are commonly
used for removing of grease and they have a wonderful solubility as well as produce a very low
quantity of foam (Hassan, Al-Obaidy and Al-Ani, 2017). When anionic surfactants are combined
with non-ionic surfactants they provide resistance to hard water. There are several kinds of non-
ionic surfactant, some of which are explained below in detail:
 Fatty alcohol poly (ethylene glycol) ether or fatty alcohol ethoxylate (FAE):
Surfactants which are made from fatty alcohol with ethylene oxide are most commonly
used non-ionic surfactant. Fatty alcohols could be of two types:
◦ Natural: These fatty alcohols are obtained from vegetable oils and fats. There are
various other ways by which fatty alcohol could be obtained but the most common
way is by decrement of either fatty esters or fatty acids (Landeck, Baden and John,
2020).
◦ Synthetic: These alcohols are composed from Ziegler method which possess alkyl
chain with even carbon atom numbers. Whereas, the alkyl chain which is obtained by
Oxo procedure could have both odd or even number of carbon atoms.
Amphoteric surfactants:
These surfactants possess dual charge on their hydrophilic end which means they have
both negative and positive charge. The dual charge of these surfactants cancel out each other and
develop a net charge of zero which is referred as zwitterionic. In alkaline solutions, these
surfactants behave as negative charge and act similar as anionic surfactants. Whereas, when
these surfactants are dissolved in acidic solutions they possess positive charge which makes them
act like cationic surfactants (Al-Ani, Hassan and Al-Obaidy, 2020). They are consisting of two
main group which are betaines and another is based on fatty alkyl imidazolines. Some of the
example of these types of surfactants include Cetylamino-acetic acid.
Role of surfactants
There are various types of detergents which could be utilized for different purposes such
as washing clothes, dishes, shampoo, shower gels, hair conditioner and many other. The role of
surfactants in laundry detergents is explained below in detail:
Laundry detergents:
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Surfactants are one of the main element in laundry detergent which remove the stain by
suspending dirt in water in order to forbid the redeposition of dirt molecules on the surface again.
The main role of surfactant is to remove dirt that normally does not dissolve completely in water.
Anionic surfactant is considered as best agent in removing dirt because it possesses negative
charge. Anionic surfactants such as alkyl ethoxylate sulfate, alkyl sulfates and soaps are
considered to be best ingredient in detergents. In case if someone is washing clothes in hard
water than the best result could be achieved by using detergent that contains non-ionic
surfactants. Detergents containing non-ionic surfactants includes ingredients like ethers of fatty
alcohol.
Laundry detergent are classified as cleaning agents which is utilized for washing dirty
clothes. This detergent could be produced in the form of powder and liquid form. In laundry
detergents the role purpose of surfactant is to act as cleansing agent by removing dirt from the
surface. They provide cleaning through the process of absorption and emulsification of dirt by
dissolving in water and also by decreasing the surface tension of water in order to modify
wetting process. The main surfactants that laundry detergent consist of are anionic and non-ionic
surfactants which contains negative and no charge on themselves respectively (Hassan, Al-
Obaidy and Al-Ani, 2017). In comparison to anionic surfactants, cationic surfactants are less
incompatible and possess poor efficiency of cleaning. Therefore, cationic surfactants are mainly
used in fabric softeners, biocides and antistatic agents.
CONCLUSION
From the above discussion it has been evaluated that surfactants are one of the most
important component in detergent as they are used to remove dirt, grease and oil stains. There are
various kinds of surfactants which are according to the charge they possess. Some of the
surfactants which have positive charge are categorised as cationic surfactants and other which
contains negative charge is known as anionic surfactants.
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REFERENCES
Books and Journals
Abney, S.E. and et. al., 2021. Laundry Hygiene and Odor Control–State of the Science. Applied
and Environmental Microbiology, pp.AEM-03002.
Al-Ani, R.R., Hassan, F.M. and Al-Obaidy, A.H.M.J., 2020. Environmental Evaluation of
Surfactant: Case Study in Sediment of Tigris River, Iraq. In River Deltas-Recent Advances.
IntechOpen.
Boza Troncoso, A. and Acosta, E., 2019. Formulating nonionic detergents via the integrated free
energy model. Journal of Surfactants and Detergents, 22(5), pp.1023-1037.
Hassan, F.M., Al-Obaidy, A.M.J. and Al-Ani, R.R., 2017. Detection of detergents (surfactants)
in Tigris River-Baghdad Iraq. IJEW, 6(2), pp.1-15.
Landeck, L., Baden, L.A. and John, S.M., 2020. Detergents. Kanerva’s occupational
dermatology, pp.1131-1143.
Vento, M. and et. al., 2019. Surfactant administration via thin catheter: a practical guide.
Neonatology, 116(3), pp.211-226.
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