The Extraction of Ethanol from Alcoholic Beverages and the Analysis of this Extract by Gas[2] - An

The Extraction of Ethanol from Alcoholic Beverages and the Analysis of this Extract by Gas[2] - An

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
The Extraction of Ethanol from Alcoholic Beverages and the Analysis of this Extract by Gas- Liquid Chromatography Flora Vo Lab Partner: Taylor Scott 13 March 2007 TA: BJ Privett Section 410: Room 401 Thurs: 1 PM – 4 PM Pledge: I pledge that no unauthorized assistance has been given or received in the completion of the work presented in this report. ________________________________
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Introduction In this two-day lab, the goal is to determine the amount of ethanol from Busch beer, Busch light beer, and a non-alcoholic Busch beer. Also, the amount of ethanol in Listerine and Vicks Cough medicine will be compared to the beer samples qualitatively. To accomplish this goal, students will learn to use solvent-solvent extractions, gas-liquid chromatography and Data Studio, which will allow the students to analyze the results with integration methods. Also, students will to construct a standard calibration plot with the standard ethanol samples, and they will construct a standard addition calibration plot with the specific beverage samples. These calibration plots will help the students determine the partition coefficient, the amount of ethanol remaining in the aqueous layer, and the percentage of ethanol in the three different beer samples. The alcoholic beverages that will be analyzed consist of many compounds which include carbohydrates, lipids, proteins, and alcohol. Therefore, one must perform solvent-solvent extractions to isolate the compound of interest, which is ethanol. The basis of a solvent-solvent extraction is to have two immiscible liquids, in which ethanol is much more soluble in one liquid. In this experiment, pentanol will be the liquid in which ethanol, the analyte, is more soluble. The beer sample is the liquid in which the analyte is much less soluble because it can be treated as an aqueous solution due to the large amount of water in it. Also, salt is added to the mixture to created a charged environment so the ethanol molecules will be more attracted to the organic layer and migrate there. The two liquids will be shaken together and the ethanol will distribute itself between the two distinct layers. To quantify the amount of ethanol in each layer, the partition coefficient (K) is used which is defined below. K = [CH3CH2OH]organic/[CH3CH2OH]aqueous
Background image of page 2
One can also calculate the fraction of ethanol remaining in the aqueous layer with the equation below. This fraction (q) is an important value since it approximates how much analyte has failed to be extracted q = naq/(naq + norg), where n is moles. This equation can be modified by substituting n = CV, where C is concentration in moles per liter and V is volume. Also, the equation can be simplified using K = Corg/Caq. Therefore, the equation can be written like this: q = Vaq/(Vaq + KVorg) It is very rare for q to be zero because the analyte is usually soluble in both the organic and aqueous solutions. Therefore, multiple extractions are needed to produce a better isolation of the ethanol. The fraction (q) remaining after n number of extraction is defined below:
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 19

The Extraction of Ethanol from Alcoholic Beverages and the Analysis of this Extract by Gas[2] - An

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online