The Transesterification process is the reaction of a triglyceride (fat/oil) with an alcohol to form esters and glycerol (Wahab Maqbool, 2010). A triglyceride has a glycerine molecule as its base with three long chain fatty acids attached. During the esterification process, the triglyceride is reacted with alcohol in the presence of a catalyst, usually a strong alkaline like sodium hydroxide. The alcohol reacts with the fatty acids to form the mono-alkyl ester, or biodiesel and crude glycerol. In most production methanol or ethanol is the alcohol used (methanol produces methyl esters, ethanol produces ethyl esters) and is base catalyzed by either potassium or sodium
On a large scale ethanol and ethanoic acid is added to get the product ethyl ethanoate and water.
In this experiment, the Fischer Esterification of an unknown acid and an unknown alcohol was used to prepare an unknown ester. Sulfuric acid was used as a catalyst in the reaction which then was put under reflux. After cooling, the pH of the solution was raised to approximately 8 using sodium carbonate. Diethyl ether was added, then the aqueous layer was removed and the organic layer was washed with sodium chloride. The aqueous layer was removed again and sodium sulfate was added. The unknown product was then identified using gas chromatography (GC) to obtain the retention time.
To transition from an alcohol to an alkene, the alcohol must be dehydrated with the help of an acid through a reaction known as an E1 mechanism.1 The first step of an E1 reaction is the formation of a carbocation intermediate. This carbocation is produced by the removal of a halogen or a substituted group.2 In this experiment, the hydroxy (OH ) group of the alcohol is removed and this produces the carbocation. The OH- group is removed due to the presence of phosphoric acid. The phosphoric acid is used in the process of adding an additional H+ to the OH- group on the alcohol and assists the OH- in leaving, making the reaction an acid catalyzed dehydration. Another reagent used along with phosphoric acid is heat, which is often used in acid catalyzed dehydration.1
The purpose of this experiment was to synthesize isopentyl acetate via an esterification reaction between acetic acid and isopentyl alcohol, using concentrated sulfuric acid as a catalyst. The product was washed with sodium hydrogen carbonate, as well as with water, then dried with anhydrous sodium sulfate. The product was then distilled using a Hickman still and characterized using infrared spectroscopy. The percent yield of isopentyl acetate was 61.52%. This may have been low due to not all of the condensed product being removed from the Hickman still, some product being lost during transfer of the product from the reaction tube into the Hickman still, or the loss of some product due to evaporation during distillation.
Stearyl alcohol prevents from end-mixture to separate back into its original oil and liquid components.
The main purpose of this lab is to determine whether or not the number of carbon molecules relate to the amount of energy emitted measured through the temperature change over the course of 2 minutes. The main three tested fuels are fuels methanol (CH3OH), ethanol (C2H5OH), propanol (C3H7OH). Based on those formulas, Propanol alcohol has 3 carbons, Ethanol alcohol has 2 carbons and methanol has 1 carbon. Based on the hypothesis mentioned above “If the number of Carbon molecules in the fuel increases, the amount of energy over 2 minutes is going to increase”. Based on the data shown above, propanol fuel had the most temperature change meaning that it burned with the most energy. Following that is ethanol fuel having the second greatest temperature
Purpose: The purpose of the experiment was to perform the acid-catalyzed Fischer Esterification of acetic acid and isopentyl alcohol to form isopentyl acetate, or banana oil, which is used in flavor industries. The equilibrium of the reaction was changed by adding an excess amount of acetic acid. The reaction was refluxed and product was purified by extraction and distillation. Isopentyl acetate was analyzed by infrared spectroscopy and 1H NMR spectroscopy.
A Fischer esterification reaction was used in the first part of this lab to convert an unknown alcohol into an ester through the help of microscale reflux, which was later identified using GC, micro-boiling point, and IR spectroscopy. In this type of reaction, an alcohol is reacted with a carboxylic acid, and is driven by a strong acid catalysis to yield ester and water. To obtain a good yield of the ester produced, Le Chatelier’s principle is exploited to remove excess water and form more ester product, by the addition of excess carboxylic acid. A trans-esterification reaction was used in part b of the experiment to synthesize biodiesel from vegetable oil through the help of microscale reflux, which was analyzed using IR spectroscopy and
After the transesterification process was complete the LEA was separated from the biofuel, and water/methanol mixture using an Erlenmeyer filtering funnel utilizing both course and fine filters (Whatman 1541-125 and 1542-125). A 1:1 solvent to water ratio (300 mL) and a 3:1 solvent to chloroform ratio (100 mL) were added to induce a phase separation. Phase separation was allowed to occur overnight. Biofuel and chloroform were separated from the methanol/water mixture using a separation funnel. The chloroform and biofuel were separated by evaporating and recovering the chloroform by heating the mixture to 62°C and then running the chloroform gas through a condenser. Samples were taken of each product and byproduct excluding chloroform so that
The formation of esters from alcohols and carboxylic acids is typically a process called esterification which is demonstrated in Equation
An ester was synthesized during an organic reaction and identified by IR spectroscopy and boiling point. Acetic acid was added to 4-methyl-2-pentanol, which was catalyzed by sulfuric acid. This produced the desired ester and water. After the ester was isolated a percent yield of 55.1% was calculated from the 0.872 g of ester recovered. This quantitative error was most likely due to product getting stuck in the apparatus. The boiling point of the ester was 143° C, only one degree off from the theoretical boiling point of the ester 1,3-dimethylbutyl, 144 ° C. The values of the
The purpose of this experiment is to prepare an ester. Esters are a type of organic compound, and these compounds are very prevalent in today's society because they contribute to scents/fragrances/aromas, flavoring, and even lubrication. Moreover, this experiment allows us to understand more of the esterification process, in which the synthesis of esters is due to the esterification reaction of a carboxylic acid and an alcohol. In this experiment, we studied ester #6. By completing the procedure for this reaction, we detected the odor of wintergreen.
Esters are organic compounds which are naturally found in many flowers and fruits, esters are also created synthetically by a reaction between a carboxylic acid and an alcohol leading the formation of an ester, and water called esterification. The reaction uses an acid catalyst to speed up the process ex. Sulfuric acid (p.51 Nelson, 2010).
In this experiment, a Fischer Esterification reaction was performed with two unknown compounds. The unknown compounds, Acid 2 and Alcohol D, were identified by using the knowledge of the reaction that took place, and the identity of the product that was synthesized. The identification of the product resulted from analysis of IR and NMR spectra.
The purpose of this lab was to synthesize the ester isopentyl acetate via an acid catalyzed esterification (Fischer Esterification) of acetic acid with isopentyl alcohol. Emil Fischer and Arthur Speier were the pioneers of this reaction referred to as Fischer Esterification. The reaction is characterized by the combining of an alcohol and an acid (with an acid catalyst) to yield and ester plus water. In order to accomplish the reaction, the reactants were