CHE 321 - Blended Learning Week 12

FATTY ESTERS

What is Fatty Esters?

• Fatty esters (FEs) are a type of ester that resulted from the combination of an oil or fat with an alcohol.

• An organic chemistry - RCOOR′ A fatty acid in which the alkyl group (R′) of a monohydric alcohol replaces the active hydrogen; for example, RCOOCH3 from reaction of RCOOH with methane.

• Biodiesels are typically fatty esters produced by the transesterification of vegetable fats and oils which results in the replacement of the glycerol component with a different alcohol.

• The most common fatty esters contained in biodiesel are those of palmitic (hexadecanoic) acid, stearic (octadecanoic) acid, oleic (9(Z)-octadecenoic) acid, linoleic (9(Z),12(Z)-octadecadienoic) acid, and linolenic (9(Z),12(Z),15(Z)-octadecatrienoic) acid.

• This holds for biodiesel feedstocks, such as soybean, sunflower, rapeseed (as canola), palm, and peanut oils. Some tropical oils, such as coconut oil, contain significant amounts of shorter chain acids, such as lauric (dodecanoic) acid.

• A variety of other fatty acids are found in minor amounts in virtually all oils and fats used as biodiesel feedstocks.

The Uses And Application Of Fatty Ester

The Uses and Application Of Fatty Ester

• As synthethic lubricants with desirable characteristics such as high thermal and oxidation stability and low volatility.

• In pharmaceuticals - as antifoaming agents, emulsifiers, thickening agents in ointment.

• Palm based methyl esters - as diesel substitutes for taxis, buses, lorries and tractors, etc.

• Used in a broad variety of different industrial applications such as cosmetics, toiletries, pharmaceuticals, food, metal working fluids, and etc.

• Properties like lubrication, mould release, consistency promotion, emolliency, stability enhancement, spreading or fatty, solvency and cleaning demonstrate the large variety of functions offered by these unique products.

Production Processes Of Fatty Esters and Its

Derivatives

Production of Fatty Esters

o Fatty alcohols are the derivatives of fatty ester

o For the production of C12–C14 alcohols, only coconut oil and palm kernel oil canbe used. Palm oil, soybean oil and tallow are the main sources for C16–C18alcohols. Rapeseed oil is mainly for fatty alcohols with 20 or 22 carbon atoms.

o Contaminants such as phosphatides, sterols or oxidation products and impuritiessuch as seed particles, dirt and water were removed during pre-treatment oftriglyceride.

o The refined triglycerides are then transesterified with lower alcohols to yieldfatty acid esters. The refined fatty acid esters (mostly methyl esters and, morerarely, butylesters) are used for hydrogenation to produce fatty alcohols.

• Transesterification of Triglycerides.• This reaction is carried out continuously with alkaline catalysts.

• Tansesterification is an equilibrium reaction and is shifted toward thedesired ester by excess methanol or removal of glycerol in order to producemore fatty alcohols.

• Fatty esters is produced from the route production of fatty acids. Meaning that, producing fatty acids, glycerine and fatty alcohols can also yield fatty esters as the derivatives through some processes.

• Fatty esters is the derivative of fatty acid and fatty alcohols is the derivative of fatty esters.

• Thermal splitting of fats and oils

Fats and oils, the naturally occurring triglycerides of fattyacids, can be hydrolyzed to fatty acids and glycerin bythermal splitting. The process is highly efficient and easy tooperate.

Types of Fatty Esters Fatty Acid Methyl Esters

Polyol Esters

Sorbitan Esters

Sucrose Esters

And others..

Fatty Acid Methyl Esters

• Fatty Acid Methyl Esters (FAME) are esters of fatty acids. The physical characteristics of fatty acid esters are closer to those of fossil diesel fuels than pure vegetable oils, but properties depend on the type of vegetable oil.

• A mixture of different fatty acid methyl esters is commonly referred to as biodiesel, which is a renewable alternative fuel. FAME has physical properties similar to those of conventional diesel. It is also non-toxic and biodegradable.

Production of Fatty Acid Methyl Esters

• FAME is produced from vegetable oils, animal fats or waste cooking oils by transesterification.

• Transesterification process glyceride reacts with an alcohol in the presence of a catalyst, forming a

mixture of fatty acids esters and an alcohol. Using triglycerides results in the production of glycerol.

Transesterification is a reversible reaction and is carried out by mixing the reactants. A strong base or a strong acid can be used as a catalyst. At the industrial scale, sodium or potassium methanolate is mostly used.

Polyol Esters

• Polyolester oil (POE oil) - a type of Synthetic oil used in refrigeration compressors that is compatible with the refrigerants R-134a, R410A and R-12. Recommended by experts as a replacement for HFC's (Hydrofluorocarbon). Along with R134A mineral oil, recommended as a replacement for R12 mineral oil as R134A does not mix well with mineral oil.

• These wax free oils are suggested for usage with chlorine free HFC systems as they provide better lubrication and stability and are more miscible with HFC refrigerants.

• They can meet the lubricity requirements to those of mineral oils used with CFC's (Chlorofluorocarbon) and HFC's. They are compatible with most lubricants in the market.

• It is noted that the viscosity of the oil increases with temperature. The dispersion behavior of this oil has also been the subject of a lot of study and also considered by some to be a good additive to engine oil.

Uses of Polyol Esters

• The use of this type of oil is in the process of being phased-in by manufacturers who use compressors in their products. The need to replace the old oils has arisen due to environmental restrictions causing incompatibility of the old oils with the new refrigerants.

• POE oils are very good solvents and easily dissolve most of the residual mineral oils that they may be replacing. So even though small amounts of the old oil may remain, it won't clog the system.

• Polyolester oil is used exclusively in jet turbine engines and often used in moving picture film cameras.

Sorbitan Esters

• (Also known as Spans) are lipophilic nonionic surfactants that are used as emulsifying agents in the preparation of emulsions, creams, and ointments for pharmaceutical and cosmetic use.

• When used alone they produce stable water-in-oil emulsions but they are frequently used with a polysorbate in varying proportions to produce water-in-oil or oil-in-water emulsions or creams with a variety of different textures and consistencies.

• Sorbitan esters are also used as emulsifiers and stabilisers in food.

• The derivative types of Sorbitan esters are :-

Sorbitan Laurate

Sorbitan Stearate

Sorbitan Oleate

Sorbitan Tristearate

And so on..

Sucrose Esters

• Sucrose esters are obtained by esterifying sucrose with methyl fatty acids. By varying the degree of esterification of the sucrose molecule it is possible to obtain emulsifiers with HLB values ranging from 1 up to 16.

• Used in many food categories such as bakery, confectionery, cereals, dairy, ice cream and sauces.

• Manufacturers have multiple reasons to work with sucrose esters, for example it can improve the production process by reducing mixing time or keeping viscosities low.

• Sucrose esters are also more used in low fat alternatives. In these products the mouth feel provided by fat has to be maximized, an emulsifier makes the fat globules much smaller and therefore provides good eating properties.

• A bakery product will have a finer crumb structure and a softer texture, the stability of dairy or sauces will be improved, the texture of a mousse finer and ice cream a better flavor.

• Although sucrose esters are categorized as emulsifiers their function is not only emulsification.

• Functions such as Aeration

Texturization

protein protection

or starch interaction

and fat or sugar crystallization

are often used.

• Sucrose esters are unique in a way that they can boost other emulsifiers and improve the air bubble structure or prevent proteins from browning or keep starches from early staling.

• The effect on sugar and fat crystallization is primarily used in confections to prevent fat bloom in chocolate and to accelerate crystallization in fine grained sugar confection.

References

• http://en.wikipedia.org/wiki/Fatty_acid_ester

• http://en.wikipedia.org/wiki/Fatty_acid_methyl_ester

• https://www.mitsui.com/jp/en/release/2015/1203968_6041.html

• http://pubs.acs.org/doi/pdf/10.1021/ef700639e

• http://www.klkoleo.com/brand/palmester%C2%AE-fatty-esters

• http://www.ccur.iastate.edu/biorenewables/publications/fattyacidoverview0105/fattyacidoverview180804.htm

• http://www.ebi.ac.uk/chebi/searchId.do?chebiId=35748

• http://www.biofuelstp.eu/factsheets/fame-fact-sheet.pdf

• http://encyclopedia2.thefreedictionary.com/fatty+ester

• http://www.drugfuture.com/chemdata/sorbitan-esters.html

• http://en.wikipedia.org/wiki/Sorbitan

• http://en.wikipedia.org/wiki/Polyolester

• http://www.sisterna.com/index.php/sucrose-esters/food/

• http://www.molecularrecipes.com/hydrocolloid-guide/sucrose-ester-sucro-2/