Download - soap and detergent

NAME : SITI FATIMAH BINTI NGAGIMAN (2011683532)

GROUP : EH 221 2B (GROUP 6)EXPERIMENT : SOAP AND DETERGENTDATE PERFORMED : 25TH MAY 2012SEMESTER : 02PROGRAMME : FACULTY OF CHEMICAL

ENGINEERING AND PROCESS (EH 221)

FACULTY OF CHEMICAL ENGINEERING May 25, 2012

NO TITTLES ALLOCATED MARKS (%)

MARKS

1. ABSTRACT 52. INTRODUCTIONS 53. AIMS 54. THEORY 55. APPARATUS 56. METHADOLOGY/

PROCEDURES10

7. RESULTS 108. CALCULATIONS 109. DISCUSSIONS 2010. CONCLUSION 1011. RECOMMENDATIONS 512. REFERENCES 513. APPENDIX 5TOTAL MARKS 100

REMARKS:CHECKED BY:

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DATE

ABSTRACT:


The experiment which is to prepare the soap and detergent had

been conducted on 25th May 2012. Basically, the experiment used to

prepare the soap and thus, to compare the properties between the soap

that had been prepared early with the synthetic detergent in the form of

precipitation, emulsification and cleaning abilities. Based on the

experiment that had been conducted, it can be concluded that the soap

has the properties of emulsifying oil whereas the detergent has not. This

is because the soap has the abilities of forming precipitates and it can be

seen clearly in the soap solution while doing the experiment. Whereas the

detergent has not forms precipitates at all. Thus, the experiment is

completed and successfully conducted.


INTRODUCTION:

Soaps and detergents are used frequently in our daily life. We use

them in many kinds of ways. We use them to wash our hands and clean

our clothes without ever really paying attention on how they work.

Beneath the plain white surface of a bar of Ivory soap lies an intrigung

history and a powerful chemistry.

Actually, it is hard to say when soap was first invented. Some

hypothesize believe that the soap had been invented by the Babylonian

in 2800 BC where soap have been excavated in clay cylinders and the

Phoenicians around 600 BC. By 1500 BC Egyptians medical scrolls

recommend a soap made from alkaline salt and animals and vegetables

oil for skin conditions. In the early history, soap was used for the purpose

of cleaning textile fibres such as wool and cotton in preparation for the

dyeing process instead of personal hygiene.

Later, the ancient Roman discovered the cleaning power of soap

accidently. At Mount Sapo, where it a place for the animals were

sacrificed, rain mixed animal fats, wood ashes and clay in to the soil.

Then, incidently, women washing their clothes by the stream found it was

much easier to wash their clothes with some of this clay mixture. Legend

links Mount sapo with the process of soap making saponification.

Interestingly, although Romans are famous for their baths, they actually

did not use soap to wash. But they coated themselves in oils and after

that used a scraping tool called a strigil to clean their bodies. However,

bars of soap were found in the ruins of Pompeii and the archeologists

believe soap was used for the laundry and occasionally on the body.


Figure 1.

Soap making was an established craft in Europe by the 7th

century and soap making center flourished in France, Spain and also Italy.

In the New World, soap makers found work in Jamestown as early as

1608. Besides, most of the early settlers made their own soap by boiling

ashes and animal fats. As world growth, the soap industry continued to

grow fairly steadily until the 20th century. While in 1916, there was a

chemical break through that promised to change the role of soap for

years to come. Thus, the Germans, suffering from a shortage of materials,

resorted to synthetic detergent. As a result, it was succesful and by 1946

laundry detergent became available to the entire American population. In

1953, sales of detergent surpassed those of soap.

Actually, soap and detergents are very similar in their chemical

properties which is same function used to wash and clean a dirt.

However, there is a significant difference between them where the soaps

are produced from the natural products while the detergents are

synthetic or man-made.

In today’s progressive world of science and technology, soap is

manufactured much like it was back then where the fats and oils are

technically heated with the presence of strong base which commonly

used is sodium hydroxide or potassium hydroxide to produce fatty acid

salts and glycerol in a process termed as saponification process. As a

matter of fact, the salt of a fatty acid is the soap, which is a soft and waxy

material that brush up the ability for cleaning purpose of water. While


processing of soap, a positive ion, usually Na+ or K+ and a negative ion

usually the anions of long-chained carboxylic acids yielded by the

hydrolysis of either animals or vegetables fats.

Futhermore, the soap tends to decrease its melting point due to

the presence of double bond which known as unsaturated with fatty acids

materials. Thus, the compounds are in liquid form at room temperature.

Technically, the vegetable fats are relatively unsaturated and liquid under

the ordinary conditions, whereas animals fats are relatively more

saturated and solid or more-solid at the same temperature. Thus, double

bonds are said to lower the melting point of a fatty acid chain because its

cis-conformation chain by a Van der Waals attraction. Hence, a lower

temperature is required for these materials to form a solid crystal lattice.

If now we can see, there a variety of detergents can be found

today, which generally contain surfactants, a builder and other additives

such as bleaching agents and enzymes. The surfactants are the parts that

are responsible for the cleaning properties of that particular detergent.

Some of them may be cationic, ionic and non-ionic. The builders indeed

are compounds responsible for removing the corresponding calcium and

also the magnesium ions in hard water.

Furthermore, there are two detergents which may not be safe as it

may concern, mostly that contains phosphates. Such detergents will end

up in wastewater and cause excessive growth of algae and other aquatic

plants. When those die, bacteris that present in the dead matter consume

oxygen which then results in the lack of oxygen left for the fish and other

aquatics lives.


AIMS AND OBJECTIVE:

For this experiment, we conducted to achieve the objective which

are to prepare a soap by using the mineral oils. Besides, the experiment

is conducted to study and compare the properties between the soap and

synthetic detergent in the form of precipitation, emulsification and also

cleaning abilities.


THEORY:

Soap is a mixture of sodium salts of various naturally occuring fatty

acids. Air buubles added to a molten soap will decrease the density of the

soap thus it will float on the water. If the fatty acid salt has potassium

rather than a sodium, a softer lather is the result. This is because the bar

soap produced in the presence of sodium hydroxide while the liquid soap

is formed in the presence of potassium hydroxide.

Theorytically, the soap is produced by a saponification or basic

hydrolysis reaction of a fat or oil. Currently, sodium carbonate or sodium

hydroxide is used to neutralize the fatty acid and convert it to the salt.

In the other words, soap is a generic term for the sodium or

potassium salts of long-chain organic acid which is fatty acid that are

made from naturally occuring esters in animal fats and also the vegetable

oils. All organic acid contain the RCOOH functional group, where R is the

shorthen notation for the complex hydrocarbon which famously known as

alkyl group. The term for R is used because the group can be very large


and for the addition for each chain has a litter effect for the chemical

reactivity. While for the ester it contain RCOOR functional group.

A soap is the sodium or potassium salt of a long chain fatty acid.

The fatty acid usually contain 12 to 18 carbon atoms which can be

expressed as term R. Solid soap usually consists of sodium salts of fatty

acids whereas liquid soaps usually are potassium salts of fatty acid.

Besides, the few examples of soaps are sodium fatty acid such as lauric

(vegetable oil), palmitic (palm oil), and stearic (animal fat).

Furthermore, the hydrocarbon chain in the soap may contain

saturated and unsaturated chains. Sodium salts are usually solid

therefore, most bars of soap are sodium salts. While potassium salts are

the basis of liquid soaps, shaving cream, and greases. Triglycerides is

formed by the combination of three molecules of fatty acid which are fats

and vegetable oils. Triglycerides included in the ester group which is

RCOOR which derived from three fatty acids. A triglyceride made from

three lauric acid molecules which shown as below:

General overall hydrolysis reaction:

Fat + NaOH glycerol + sodium salts/ fatty

acid


Figure 2 - the hydrolysis of triglycerides

For the figure above, it formed by the saponification of a

triglyceride with the sodium hydroxide. Actually, saponification is a

process that produce soap usually from fats and lye. In the other words,

saponification involves base hydrolysis of triglycerides, which are esters

of fatty acid to produce a product which is sodium salt od a carboxylate.

Besides, saponification processes also produce glycerol.

The mechanism by which esters are cleaved by base involves

nucleophilic acyl substitution. Then the hydroxide anion, OH- adds to

attacks the carbonyl group of the ester. Then the intermediate product is

formed is orthoester.

Figure 3 - the mechanism of ester (1)

At this stage, the alkoxide is more basic than the conjugate base of

the carboxylic acid, and hence the proton is transfer rapidly and directly it

form a stabe carboxylic acid compound.

Figure 4 - the mechanism of ester (2)

After that, it continue by reaction between the RCOOH with the

alkoxide anion and then formed a product of carboxylic anion and a

alcohol. But with the presence of NaOH, the carboxylic acida are

converted to their sodium salts which is RCOO-Na+.


The saponification of triglyceride produced 3 fatty acid which is

soap and the glycerol but the alkyl group in the triglyceride may or may

not have the same chain length which known as the number of carbons.

Figure 5 - the hydrolysis of triglycerides

Since the cleansing action of soaps depend upon the fact that they

ionize readily in water, how can you imagine if the ionic at the end

molecule is lost its charge. Thus, the soap would no longer clean and

emulsify the oil and dirt. But in facts, it would happen in hard and acidic

water. This is because the hard water contain metal cations such as Ca2+

and Mg2+ that will react with the charged ends od the soaps and directly

form the insoluble salts.

As the conclusion, the synthetic detergent were developed to

overcome this kind of problems. Actually, the detergent has a similar to a

soaps in having an ionic and nonpolar end but it have a different structure

which have sulfonate end. The difference in polar groups is one of the key

distinctions between a soap and a synthetic detergent. The synthetic

detergent form micelles and cleanse in the same manner as soaps but if

it released into rivers and lakes it can cause explosive growth of algae.

Thus, it can cause decay of the aquatic ecosystem due to deoxygenation

from the decomposition of dead algae.


A micelle is a spherical shape that is formed resulting from the

negatively charged heads on the soap molecules. They then orient

between them, where the non polar tails rearrange towards the centre of

the micelle and then the hydrophilic site facing the water. In the presence

of oil and dirt, the non-polar head interact with them and gathered it to

the centre of the micelle. Technically, this is how the soap works. When

rinsed with water, the micelle together qith the dirt washed away. Soap is

theoretically acting as an emulsifying agent, where emulsion is the

dispersion of a liquid in asecond immiscible liquid.

Figure 6 - the micelle of the soap

The structure below is a sodium lauryl sulfonate that contain in the

synthetic detergent. In facts the sulfonic acids are more stronger than

carboxylic acids, hence the synthetic detergent does not form any

precipitate in the acidic solution. Besides, in the hard water, the

detergent do not form insoluble salts compare with the soap. As a

conclusion, the synthetic detergents remain soluble in both acidic and

hard water.

Figure 7 - the structure for synthetic detergent


REAGENTS:

1. Vegetable oil,

2. Ethanol

3. 6M sodium hydroxide

4. Saturated sodium chlorde

5. Synthetic detergent (dynamo)

6. CaCl2 solution

7. MgCl2 solution

8. FeCl2 solution

9. Mineral oils

10.1M hydrochloric acid

11.Tomato sauces.

APPARATUS:

1. Erlenmeyer flask

2. Measuring cylinder

3. Beakers

4. Magnetic stirrer

5. Glass rod

6. Retort stand and clamp

7. Vacuum filtration apparatus

8. Filter paper

9. pH meter

10.test tubes with racks

11.dropper

12.petri dish

13.cloth strips

PROCEDURES:

PART A: SOAP PREPARATIONS:


1. 12.5 ml of vegetable is placed in a 250 ml Erlenmeyer flask. 10mL

of ethanol and 12.5mL of 6M sodium hydroxide solution are added

to the flask. The mixture is stirred using a stirring bar to mix the

contents of the flask. The alcohol is carefully smelled by wafting it

towards our nose.

2. The 250 mL of flask is heated in a 600mL boiling water bath.

Figure 8 - heating the mixture in the boiling water bath

3. The mixture is stirred continuously during the heating process to

prevent the mixture from foaming. If the mixture should foam to

the point of nearly overflowing, the flask is removed from the

boiling water until the foaming subsides, then the heating is

continued. The mixture is heated for 20-30 minutes or until the

alcohol odor is no longer detectable.

4. The paste like mixture is removed from the water bath and the

flask is cooled in a ice bath fro 10-15 minutes.


5. While the flask is cooling, the vacuum filtration apparatus is

assembled as shown in the figure below. The vacuum filtration

secured to a ring stand with a utility clamp to prevent the

apparatus from toppling over.

Figure 9 - the vacuum filtration apparatus

6. A piece of filter paper is weighed to the nearest 0.001g and the

mass is recorded. The filter paper is placed inside the Buchner

funnel. The paper is moistered with water so that it fits flush in the

bottom of the funnel.

7. Once the flask has cooled, 150 mL of saturated sodium chloride

NaCl solution is added to the flask to “salt out” the soap.

8. The water at the aspirator is slowly turned on. The mixture from

the flask is poured into the Buchner funnel. Once all of the liquid


has filtered through the funnel, the soap was washed with 10 mL of

ice-cold water. The suction filtration is continued until all of the

water is removed from the soap.

9. The soap is removed from the funnel and pressed between two

paper towels to dry it. The filter paper and dried soap are weighed

and the mass is recorded to the nearest 0.001 g and the mass of

the soap determined by difference and then the mass is then

recorded.

PART B: COMPARISON OF SOAP AND DETERGENT PROPERTIES

(PRECIPITATION AND EMULSIFYING )

1. A stock soap solution is prepared by dissolving 2g of the prepared

soap in 100 mL of boiling distiiled water. The mixture is stirred until

the soap has dissolved and the solution is allowed to cool.

2. Step 1 is repeated using 2 g of synthetic detergent. When both

solution are cool, the pH of each solution is determined using pH

meter.

3. Three test tubes are labelled as test 1, 2 and 3. 4 drops of minerals

oil are added to each test tube. 5 mL of distilled water is added to

test tube 1. 5 mL of stock solution is added to test 2 and 5 mL of

synthetic detergent is added to test tube 3.

4. Each solution is mixed by shaking and let stand for three to five

minutes. The solution, if any that emulsifies the oil by forming a

single layer is noted.

5. The mixtures are poured into the Waste Container. The three test

tubes are cleaned and dried.

6. Three more test tubes are labelled as test tube 1,2 and 3. 2mL of

stock solution is placed in each of the three test tubes. 2mL 1%

CaCl2 solution is added to test 1. 2mL of 1% MgCl2 solution is

added to test tube 2 while 2mL of 1% FeCl2 solution is added to

test tube 3. Each test tube is shaken to mix the solutions. The

observations are recorded.

7. 4 drops of mineral oils are added to each of the test tubes in step

6. Each test tube is shaken to mix the solutions and the solutions


are left to stand for three to five minutes. The solutions, if any, that

emulsifies the oil by forming a single layer is noted.

8. Step 6-7 is repeated using 2 mL of stock detergent solution. The

solutions that precipitated are observed.

9. The solution, if any, that emulsifies the oil by forming a single layer

is noted.

10.The mixtures are poured into the Waste Container. The test tube

are cleaned and dried.

11.5 mL of stock soap solution is poured in cine clean test tube and 5

mL of stock detergent solution in a second test tube. 1M HCl is

added one drop at a time to both solution until the pH in each tube

is equal to 3. The number of drops of acid added to each mixture is

counted. Any precipitate formed in either mixture is observed.

12.1 drop of mineral oil is added to each test tube in step 11. Each

test tube is shaken to mix the solution. Any emulsification formed

in either mixture is observed.

PART C: COMPARISON OF CLEANING ABILITIES OF SOAP AND

DETERGENT.

1. The three beakers are cleaned, dried and labeled. Then 20 mL of

stock soap solution that from step 1 is placed in the first beaker.

After that, 20 mL of stock detergent solution from step 2 is placed

in the second beaker. 20 mL of tap water is added in a third

beaker.

2. Three cloth test strips that have been soaked in tomato souce are

obtained and then one strip is placed in each of the beakers.

Repeatedly, each solution is stirred with a stirrer bar for 5 minutes.

3. The cloth strips is removed from the soap and detergent solution

and then the excess water is squeezed out. Each cloth strip is

observed and compared to determine their relative cleanliness.


RESULTS:

PART A : SOAP PREPARATION.

Mass of filter paper 0.4692 g

Mass of petri dish + filter paper 2.0632 g

Mass of petri dish +filter paper +

soap

51.2267 g

Mass of soap recovered 49.1635 g

PART B : COMPARISON OF SOAP AND DETERGENT

PROPERTIES.

Test (1) : The comparison of the pH value of soap and

detergent.

Name of the

sample

Soap prepared Dynamo

Mass 2.0808 g 2.0810 g

pH value 10.086 8.050

Conclusion: The soap that had been prepared is more basic that

the detergent because the pH value of soap is more than the

detergent


Based on the result above, between soap and detergent, the pH

value of detergent is 8.050 while the soap is 10.086. Thus, the

soap prepared is more basic compare to the detergent.

Test (2) : The comparison of emulsification of soap and

detergent.

Test 1 Test 2

Test 3

Name Test 1 Test 2 Test 3

Sample Distilled water Stock soap Stock detergent

Test 4 drops mineral

oils + 5 mL

distilled water

4 drops mineral

oils + 5 mL stock

soap

4drops mineral

oils + 5 mL

synthetic

detergent


Observation The solution form

2 layer with water

at the bottom

while oil at the

upper part

The solution

become milky and

not form any

layer.

The solution is

pale blue in color

and form 2 layer

with the oil at

the upper part

Emulsificati

on

No Yes No

Emulsification can be described as the solution that form is in a

single layer. Thus, based on the test above, the emulsification had

occured in the stock soap solution which is form milky in solution.

While the distilled water and stock detergent do not occur any

emulsification because there are oil layer at the upper part of the

solution for both samples.

Test (3) : The comparison of properties of soap and detergent

in hard solution.


The solution of soap with 1) FeCl2, 2) MgCl2 and 3) CaCl2.

System Precipitate Oil emulsified

Soap Synthetic

detergent

Soap Synthetic

detergent

2 mL CaCl2

+ 4 drops

mineral oils

Colourless

with white

precipitate

No Yes Form single

layer

2 mL MgCl2

+ 4 drops

mineral oils

Milky and

have a

white

precipitate

No Yes Form 2

layers and

the oil at the

upper part

2 mL FeCl2 +

4 drops

mineral oils

Orange in

solution

and have

orange

precipitate

No Yes Form single

layer

Based on the test above, the soap have the precipitate of

properties if compare with the synthetic detergent that does not

formed any precipitate although react with either CaCl2, MgCl2 nor

FeCl2.

From the result above, we can observe that when soap mixed with

CaCl2, the soap solution change to colourless with the present of

white precipitate while the synthetic detergent change color into

light blue and does not have oil emulsified.

When mixed with MgCl2, the soap become milky solution and also

presence the white precipitate while the synthetic detergent only

change in very light blue color and consist of oil emulsification in

the form of 2 layers.

Lastly, the soap change into orange color in solution with the

presence of orange precipitate while compare to the synthetic


detergent it only change into yellowish color and does not form any

precipitate and also oil emulsified.

Test (4) : The comparison of soap and detergent in acidic

solution by using 1M HCl

Sample Soap Synthetic detergent

Initial pH 8.821 5.860

Final pH 3.010 3.015

Drops of 1M HCl 28 drops 16 drops

Observations The solution become

milky while droping

the HCl solution.

The solution is clear and

not form any precipitate

Add the mineral oil for both samples

Observations Form white

precipitate

Not change

For the test in the acidic solution we can observe that the soap has

a high value of pH reading compare with the synthetic detergent

and the soap formed the precipitate when react with the acid and

not for the synthetic detergent.

Test (5) : Cleaning comparison of a soap and detergent


The cleaning ability by 1) tap water, 2) synthetic detergent and

3) soap

Samples Tap water Synthetic

detergent

Soap

Cleanliness Not clean Very clean Slightly clean

Observation No effect the

solution

Not effect the

solution

The solution

seen have a

precipitate

For the test above, it more concentrate to determine the relative

cleanliness for the tap water, synthetic detergent and soap.

Based on experiment conducted, the synthetic detergent shown

the high relative cleaanliness compare with the soap and the tap

water.

The relative cleanliness can be conclude as:

tap water < soap < synthetic detergent


DISCUSSION:

In the saponification process, the fatty acid carboxylate ions are

formed in the presence of the strong base which is used sodium

hydroxide, NaOH for this experiment. Then, these carboxylate ions are

the conjugate bases of the fatty acids therefore, it is able to accept a

proton to formed the stable compound. When it placed into water, these

conjugate bases are able to accept the proton from any souces including

the water.

For the hard water, it can be known as the water that consist of

calcium ion, Ca2+ and magnesium ions, Mg2+. These ions are leached from

the ground water flowing over rock formations containing limestone and

also other minerals. Thus, the hard water interferes with the cleaning

action of soap. That why when the soap is react with the mineral ions that

contain in the hard water, it will formed the precipitate. So that, the

precipitate leaves a deposit on clothes, skin and hair.

The synthetic detergents have undeniably replaced soap for many

cleaning jobs around the home. Thus, the development of synthetic

detergent by chemist actually was a great advantage for people with

relatively hard tap water in their homes.

However, although the synthetic detergent have the advantages

compare to the soap, but there is a significant issue regarding the use of

synthetic detergent that is the biodegradability of some of its

components. In fact, many of the surfactants initially used in detergents

were not biodegradable whereas soaps are biodegradable, apparently

can be degraded by bacteria.

From the observations obtained from the experiement, the soap

form the precipitate in all of the solutions added which are CaCl2, MgCl2

and FeCl2 as well emulsifies the oil. So that, this may not appear as a

good characteristics for the soap as the cleaning agent if there formed

precipitate and emulsifies oil on the cloth.


Furthemore, compare to the detergent, it is a better cleaning agent

because it not formed any precipitate while react with the mineral that

may be contains in the hard water. Besides, this is because the detergent

can cleaned without involving any precipitate or oil emulsification.

CONCLUSION:

Followed by the objectives of the experiment which are to prepared

the soap and used to compare the properties of soap and detergent

which are precipitation, emulsification and cleaning abilities. thus, the

soap is succesfully prepared and all the comparison of properties had

been observed and recorded.

For the test 1 which is to compare the pH value of soap prepared

with the detergent. The soap has a high value of pH reading if compare

with the detergent which the reading recorded is 10. 086 while the pH

value for detergent that had been recorded is 8.050. Thus, it can be

concluded that the soap is more alkaline than the detergent.

Next for the second test, which is to compare the oil emulsification

for the 3 kinds of samples which are distilled water, soap solution and

also synthetic detergent. From the observations, the distilled water and

the synthetic detergent do not emulsified the oil while the soap

emulsified the oil which formed the solution milky. Thus, this can be

concluded that the soap is not the good cleaning agent which has the

properties of emulsification of oil.

In addition, for the test 3 and 4 which are to compare the soap and

detergent in the formed of precipitation and emulsification in the hard

and acidic solution. From the experiment conducted, it can be concluded

that the soap has the properties of emulsifying oil whereas the detergent

has not. Besides, the soap solution seen clearly can be observed formed

the precipitate when react with the hard water and also the acidic

solution whereas the detergent does not form any precipitate in all tests

that had been conducted in the experiment.


For the lastly test which is cleaning abilities between 3 types of

samples which are tap water, soap and detergent. From the result and

figure above, we can make a conclusion that the synthetic detergent is

the most good of cleaning agent compare to the tap water and soap

which do not clean the cloth strips that contain tomato sources cleanly.

RECOMMENDATIONS:

There are a few recommendations that will significantly produce

better observations which will not deviate much from the theoretical

observations.

Firstly, the experiment should be repeated twice in order to get

more accurate observations. This is because if the experiments are

conducted twice, thus the observations might be more convincing when

the average is taken.

The most important, use a safety equipment and avoid contact

with any chemical reagents involved. If there a contact with the chemical,

directly wash the hands and don’t forget to wash hand agains before

leaving the laboratory.

While doing the experiment, focus and recorded any change of the

solution and for the color change prepared the white paper as the

background. Thus, the color change can be observed clearly and then it

must be recorded.


REFERENCES:

1. Experiment in General Chemistry Featuring Measuring Net, Bobby

Shanton, Lin Zhu, C.H.Atwood, 2005, Brooks/Cole Laboratory

Series,USA.

2. Organic Chemistry(third editions), R.T.Morrison & R.N.Boyd,1973,

Allyn and Bacon,Boston.

3. Fundamentals of General, Organic and Biological Chemistry (third

edition), J.McMurry, M.E. Castellion,1999.Prentice Hall,Inc.Upper

Saddle Rier,New Jersey.