Layout (AC) Abstract/Intro

(AC)M&M (AC)Results (AC)Discussion

Fats and Oils; Soaps and Detergents

Adam Cromptona, Einar Óskar Friðfinnssonb

aasc1@keilir.net, beinarof@keilir.net

Keilir Institute of Technology, Keilisbraut 775, 235 Reykjanesbær, Iceland.Instructors: Daniel Coaten

Experiment 23.September.2014; Sent to instructor 28.September.2014

Abstract

This paper describes an experiment were a soap was made fromoils. Ordinary soaps are sodium salts of long chaincarboxylic acids; they are created by alkaline hydrolysis, orsaponification of fats or oils (Handout).  The saponificationwas done with the use of a reflux condenser, were the oil,ethanol, water and sodium hydroxide was allowed to react andboil, without loss of product. Next the reaction mixture waspoured into a strong salt solution, here the soap wasprecipitated. The soap was

then

collected and dried by way of vacuum filtration. Finally thesoap was tested for its emulsifying properties, against brandname soap. A more in depth description of this experimentfollows in the report, along with calculation, measurementsand observations.

Table of contents

Figures:....................................................4

1 Introduction..............................................5

2 Methods and Materials.....................................62.1 Materials.............................................6

2.1.1.............................................Reactants..................................................6

2.1.2.................................Laboratory Equipment..................................................6

2.1.3......................................Safety Equipment..................................................6

2.2 Methods...............................................72.2.1.............................Properties of Glycerides

..................................................72.2.2....................Precipitation of a Soap from Oil

..................................................72.2.3......................Properties of Soap and Syndets

..................................................8

3 Results...................................................83.1 Properties of Glycerides..............................83.2 Preparation of The Soap From Oil......................93.3 Properties of Soap and Syndets........................93.4 Percentage Error......................................9

4 Discussion...............................................10

References.................................................11

Pre-lab and Post-lab Questions.............................12

3

Figures:Figure 1. Shows how the Reflux apparatus was set up........7

Figure 2. Soap being precipitated as the solution waspoured into a strong salt solution..................7

Figure 3. The soap collected by vacuum filtration,undergoes one more vacuum filtration to removeany remaining moisture..............................8

4

1 IntroductionThe aim of this experiment was to create soap from oils,using skills and techniques that have been previously used inthe laboratory. Other side experiments were to determine thesolubility of solvents in different oils and to test theemulsifying power of the soap created in the lab.

Green chemistry also known and sustainable chemistry is a newsub-discipline of chemistry that aims towards reducingpollution and releasing harmful chemicals to the environment.This discipline also strives for yield efficient of chemicalproducts by modifying how chemicals are designed and used(Green Chemsitry). Even governments are backing thisinitiative, were emphasis is being placed on reduction orelimination of the production or hazardous substances; thisresearch has expanded to include the development of greensolvents, which is interest to this report. The goal howeverwas not to regulate the quantity and emissions, but to limitindustry in order to cap the amount of pollution generated(Environmental Protection Agency (EPA)).

Glycerides, which are more correctly knows an acyglycerols,are esters formed from glycerol and fatty acids. Glycerol hasthree hydroxyl functional groups, which can be esterifiedwith 1-3 fatty acids to create monoglycerides, diglycerides,and triglycerides. Vegtable oils and animal fats containmostly triglycerides, but are mostly broken down by an enzymecalled lipases, into mono and diglycerides and free fattyacids.Soaps are formed from the reaction of glycerides and sodiumhydroxide. The product of this reaction is glycerol and saltsof fatty acids, the fatty acids emulsify oils, which resultsin the removal of oily dirt with water (Sasol Olefins).

Soap has been knows for at least 2300 years, according toPliny the Elder. Soap was mostly made in civilizations aroundthe world from animal’s fats and wood ash. It however was notused for washing or cleaning until the second century after

5

Christ, and it had previously been used as a medicine.As late as 1672, when a German names A. Leo, sent Lady VonSchleinitz a parcel containing soap from Italy, heaccompanied a detailed description on how to use it.English soap makers appeared at the end of the 12th Centuryin Bristol. In those days all soap makers had to a pay a dutyon all soap that was made, and after the Napoleonic wars thistax rose as high 3 pence per pound. Soap boiling pans werefitted with lids that could lock, so the tax collectors couldprevents production of soap under the cover of darkness. Thistax was not lifted until 1853, were in the 19th Century soapcame into such common use such that Justus von Liebig, aGerman chemist declared that the quantity of soap consumed bya nation was an accurate measure of its wealth andcivilization (Britannica, 2014).

6

2 Methods and Materials

2.1 Materials2.1.1 Reactants

The following reactants were used in the experiment:Vegetable oil, ethanol, water, sodium hydroxide, table salt,“clean n fresh” dish soap, hexane, dichloromethane, deionisedwater.

Expected amount Actual amount

vegetable oil 10g 11.00g

ethanol 17.5mL N/A

deionised water 17.5mL N/A

sodium hydroxide 10g 10.16g

table salt 50g 38.99g

“clean n fresh” dish soap

1g 1.08g

2.1.2 Laboratory Equipment

The following equipment was used in this experiment: Refluxcondenser, 100mL round bottom flask, Stuart® heat stirrerCB162, boss, clamps, 75mm deep crystallization dish,thermometer, glass stirring rod, Stuart® stirrer CB161, testtubes, 25mL pipette, 2mL pipette, Whatman® qualitative 4 70mm

7

diameter filter papers, 5mL syringe, Buchner funnel, filterflask, balance- OHAUS® item PA4102, Buchner funnel.

2.1.3 Safety Equipment

The following safety equipment was used in the experiment:Safety goggles, lab coat, latex gloves, closed toe shoes.

2.2 Methods2.2.1 Properties of Glycerides

In four test tubes, 0.5mL of vegetable oil was placed in eachtest tube. Then 1mL of the following solvent was added toeach of the test tubes: Water, ethanol, dichloromethane andhexane. Each test tube was then shaken and noted if thevegetable oil had dissolved or not, if any solvent had notdissolved the vegetable oil, an additional 5mL of thecorresponding solvent was added to the mixture. It was thennoted if the extra solvent had or had not dissolved the oil.This experiment was repeated, but instead of vegetable oil,glycerol was used instead.

2.2.2 Precipitation of a Soap from Oil

The experiment started by assemblingthe reflux apparatus and heating thevegetable oil bath. At this time 35mLof deionised water and ethanol weremixed in a 1:1 ratio by volume, 10gof sodium hydroxide was added to the

mixture and stirredwith a glass roduntil it haddissolved fully.Then the mixture was

8

Figure 1. Shows how theReflux apparatus was set up

placed into a 100mL round bottom flask, 10g of vegetable oiland a magnetic stirrer was added. Joint grease was applied tothe bottom of the reflux condenser, then the round bottomflask was attached. The reaction vessel was then lowered intothe hot oil bath, until the water line of the reaction vesselmet level of the oil bath. Enough heat was applied untilboiling of the reactants was observed. Careful monitoring ofthe condensation within the reflux chamber gave clues onwhether to increase the flow within the spiral tube.Subsequently, as some reactants became stuck to the side ofthe reaction vessel it was disconnected and swirled gently toreturn them to the solution.

Whilst the solution was boiling, a strong salt solution wasmade with: 39g of salt with 150mL of deionised water wasdissolved in a 400mL beaker. To help the solution dissolvethe beaker was placed on a stirring plate and a magneticstirrer was added into the solution.

Once the solution in the round bottom flaskhad reached saponification, which is where ahomogeneous solution was created. The reactionvessel was removed from the reflux condenserand poured directly into the strong saltsolution; the mixture was allowed to stir forseveral minutes.

The precipitated soap was collected through vacuumfiltration, with the use of a Buchner funnel and filterpapers. As the filter would become clogged from the collectedsoap, the soap was collected and a freshfilter paper was placed on the Buchnerfunnel. The process was repeated until allthe mixture had been through vacuumfiltration. The collected soap was then putthrough vacuum filtration once more to removeany moisture.

9

Figure 2. Soapbeing precipitatedas the solution waspoured into astrong saltsolution

Figure 3. The soapcollected by vacuumfiltration,undergoes one morevacuum filtrationto remove anyremaining moisture

2.2.3 Properties of Soap and Syndets

1g of the soap created was boiled and dissolved in 50mL ofdeionised water. In a similar manner a solution of commercialsyndet was created using “clean n fresh” dish soap. Fourdrops of vegetable oil was placed in 3 test tubes, 5mL ofdeionised water, 5mL of the laboratory made soap solution and5mL of syndet soap solution were placed into each test tubesrespectively, and shaken. Each test tube was observed to seehow well the oil was emulsified.

3 ResultsThe following results show the solubility of fats and oils innon-polar solvents, the emulsifying properties of the soapmade in the laboratory, and the percentage error in weighing.

3.1 Properties of GlyceridesThe following results display in tables the solubility ofvegetable oil and glycerol when different solvents are added.

Table 1. Shows the solubility of vegetable oil when the followingsolvents are added

Dissolved Dissolved withadditionsolvent

did notdissolve

Water XEthanol XDichloromethane

X

Hexane X

Table 2. Shows the solubility of glycerol when the following solvents areadded

Dissolved Dissolved with did not

10

additionsolvent

dissolve

Water XEthanol XDichloromethane

X

Hexane X

3.2 Preparation of The Soap From OilThe yielded amount of soap that was created from oil in thelab was 10.63g.

3.3 Properties of Soap and SyndetsThe following results and observations show each solutionsability to emulsify vegetable oil.

Table 3. Shows the emulsifying properties of each solution

dissolved Did not dissolveDeionised water XLaboratory made soap solution

X

Syndet solution X

It was observed that the laboratory made soap solution andthe syndet solution, appeared to be equally as emulsified.Weighed

3.4 Percentage Error

%error=uncertainty

weighedamount∗100=( 0.01g11.00g

∗100)+( 0.01g10.18g∗100)+( 0.01g38.99g

∗100)+( 0.01g10.63g∗100)=0.31%

11

4 DiscussionThe aim of this experiment was to produce soap from oil,using techniques and skills that have been learned inprevious chemical experiments. Equipment such as Buchnerflask which was used to remove a precipitated solid from aliquid, and a reflux condenser which was used to condense anyevaporating liquid, and  return it to the reaction vessel,resulting in no loss of product due to evaporation. These arejust a few examples of skills and techniques that have beenlearned in previous experiments used in this one. Theexperiment went well and was completed fully within the timeframe; more than 10g of soap was collected and tested to seeits emulsifying qualities. The soap was then fabricated intoa desired shape and placed into a dehydrating vacuum bowl.

The results for the experiment to determine solubility, needslittle or no discussion as the table clearly displays thesolubility of each substance. But students agree it would beinteresting to see what the effect would be if differenttypes of solvents were used.

The percentage error was calculated for each weighing, but itis not of much relevance as the final quantity of soapcollected was not of much importance, however the quality ofsoap was. In context with the final amount of soap, it mustalso be noted considerable amount of soap was lost as itstuck to the filter papers.

The most important point to be discussed was the ability ofthis lab-made soap to emulsify. As can be seen from theresults, it was able to emulsify the amount of vegetable oilthat was added to the test tube. By repeating the process andcomparing the outcome of commercial brand soap and the lab-made one, there was no real difference; the emulsifying powerof the lab-made soap was on par with that of the brand-namesoap.

It would be interesting to do further tests on the soap thatwas made against the brand-name soap used. Experiments suchas: Adding more vegetable oil to each test tube, to determinewhat soap is better at emulsifying larger amounts and at what

12

point do they lose their emulsifying abilities. Anotheralternative could be using different kind of fats and oils,so observations could made in regards to both thecharacteristics of the soap and the fats and oils.

13

ReferencesBritannica. (2014). Fat. Retrieved from

http://www.britannica.com/EBchecked/topic/202365/fat?anchor=ref244906

Britannica. (2014). Soap and Detergent. Retrieved fromhttp://www.britannica.com/EBchecked/topic/550751/soap-and-detergent/

Environmental Protection Agency (EPA). (n.d.). (Britannica) RetrievedSeptember 13, 2014, fromhttp://www.britannica.com/EBchecked/topic/189191/Environmental-Protection-Agency-EPA

Green Chemsitry. (n.d.). (Britannica) Retrieved September 12,2014, fromhttp://www.britannica.com/EBchecked/topic/917173/green-chemistry

Handout. (n.d.). Organic Chemsitry lab 3.

Kaparthi, R. (1959). Solubilities of vegetable oils inaqueous ethanol and ethanol-hexane mixtures. Journal of theAmerican Oil Chemists’ Society , 77-80.

Sasol Olefins. (n.d.). Excipients for Pharamaceuticals,partial glycerides.

14

Pre-lab and Post-lab QuestionsQuestions, page 1

Fats are of non-polar carbon-hydrogen bonds (which don't formhydrogen bonds like water) in the tails of fatty acids andare highly hydrophobic. As a result the fat molecules do notinteract well with water molecules, so they are 'repelled' bythe water and do not dissolve. Also Fats have lesser specificgravity than water.

Both animal fats and vegetable oil are triesters of glycerol(triglycerides). They are formed by reacting 3 molecules of an aliphaticcarboxylic acids with one molecule of glycerol.

15

Both soaps and detergents have long hydrocarbon tails and polar heads.The hydrocarbon content solubilizes greasy dirt in water. The polar headgives compatibility with water. Soaps are usually sodium salts of fattyacids like stearic:

16

Questions, page 2

Glycerol is soluble, whereas triglycerides are insoluble dueto the fatty acid chains making the molecule nonpolar.

17

Hexane, as it dissolve the vegetable oil, and it is not asharmful to a human as dichloromethane

18

Questions, page 3

Fats contain more saturated fatty acids, while the oilcontains unsaturated fatty acids .

19

Vegetable fats contain one, or more, carbon double bondswithin its structure and are therefore unsaturated. Animalfats contain only single carbon-carbon bonds and aretherefore saturated

20

Questions, page 4

Saponification is a chemical process that produces soap fromfatty acid derivatives Traditionally, saponification involveshydrolysis of esters under basic conditions to form analcohol and the salt of a carboxylic acid (carboxylates)Saponifiable substances are those that can be converted intosoap

Clumps of precipitate were formed; an emulsion was formed ofsoap and salt

21

Then washing the soap on a buchner funnel with cold waterwill remove the glycerine.

Questions, page 5

The ability to easily emulsify fats and oils readily.

22