Key Difference – Denatured vs Undenatured Ethanol
The key difference between denatured and undenatured ethanol is that denatured ethanol is ethanol containing additives that make it unsafe to drink whereas undenatured ethanol is ethanol with no additives or denaturants.
Ethanol is an organic compound containing C, H and O atoms. The chemical formula of ethanol is C2H5OH. There are few types of ethanol named as 95% ethanol, absolute ethanol and denatured ethanol. 95% ethanol is the highest concentration of ethanol that can be obtained by distillation. Absolute ethanol contains around 99% ethanol along with some trace amounts of additives such as benzene. These two forms are known as undenatured forms of ethanol. Denatured ethanol contains a high amount of additives and denaturants.
CONTENTS
1. Overview and Key Difference
2. What is Denatured Ethanol
3. What is Undenatured Ethanol
4. Side by Side Comparison – Denatured vs Undenatured Ethanol in Tabular Form
5. Summary
What is Denatured Ethanol?
Denatured ethanol is a form of ethanol containing a high amount of additives and denaturants that makes it poisonous. Denatured ethanol has bad taste and foul smell that makes it unsafe for drinking. Sometimes it is also added with some dyes to distinguish denatured ethanol from undenatured ethanol. The process of denaturing ethanol does not alter the chemical structure of ethanol or decompose it. Ethanol is only altered to make ethanol undrinkable.
Figure 01: Dyed Denatured Ethanol
The additives that can be found in denatured ethanol are methanol, isopropanol, pyridine, etc. These are added to get the poisonous ethanol and sometimes denatonium is used to make the ethanol bitter. The purpose of producing denatured ethanol is to reduce recreational consumption and to reduce taxes on alcoholic beverages. The traditional additive used for denaturing ethanol is 10% methanol. Denatured ethanol is cheaper than undenatured forms of ethanol.
What is Undenatured Ethanol?
Undenatured ethanol is the pure form of ethanol that contains no or fewer additives and denaturants. There are two forms of undenatured ethanol named 95% ethanol and absolute ethanol. These forms are known as “pure” forms of ethanol.
95% ethanol contains 9.5:10 ratio of ethanol: water. This means, 95% ethanol has 95 mL of ethanol per each 100mL water. This ethanol form is known as an azeotrope (the ratio between ethanol and water is equal in both liquid and vapour states).
Figure 02: Absolute Ethanol
Absolute ethanol is a purer form than any other form of ethanol. That is because it contains 99-100% ethanol. This form of ethanol is very useful in laboratory techniques that are very sensitive to the presence of water. To obtain absolute ethanol via distillation, additives are used during the distillation process. These additives can break down the azeotrope state of ethanol and allow more ethanol to be distilled. Therefore the absolute ethanol may contain some additives such as benzene but in trace amounts.
What is the Difference Between Denatured and Undenatured Ethanol?
Denatured vs Undenatured Ethanol |
|
| Denatured ethanol is a form of ethanol that contains a high amount of additives and denaturants, which makes it poisonous. | Undenatured ethanol is the pure form of ethanol that contains no or fewer additives and denaturants. |
| Composition | |
| Denatured ethanol contains a high amount of additives and denaturants such as 10% methanol. | Undenatured ethanol contains ethanol and water mixtures, but there can be trace amounts of additives such as benzene . |
| Purpose | |
| Denatured ethanol is produced to reduce the recreational consumption of ethanol and to reduce taxes. | Undenatured ethanol is drinkable and has many laboratory applications as well. |
| Properties | |
| Denatured ethanol has a foul smell, bitter taste and it is poisonous. | Undenatured ethanol has a characteristic alcoholic odour and a sweet taste. |
Summary – Denatured vs Undenatured Ethanol
The difference between denatured and undenatured ethanol is that denatured ethanol is ethanol containing additives that makes it unsafe to drink whereas undenatured ethanol is ethanol with no additives or denaturants.
Reference:
1. “Which Type of Ethanol Should I Use?” Bitesize Bio, 13 June 2012. Available here
2. “Denatured Ethanol.” Wikipedia, Wikimedia Foundation, 10 Mar. 2018. Available here
3. “Denatured vs Undenatured Ethanol.” ASK DIS, 1 Jan. 1970. Available here
Image Courtesy:
1.’Denaturat’By Hiuppo – Own work, (CC BY-SA 2.5) via Commons Wikimedia
2.’Sample of Absolute Ethanol’By LHcheM – Own work, (CC BY-SA 3.0) via Commons Wikimedia