What is the other 4% in 96% ethanol?

Ethanol 96% is a commonly used solvent in various industries, including pharmaceuticals, cosmetics, and automotive. But have you ever wondered what makes up the remaining 4% of this ethanol solution? While 96% consists of pure ethanol, the remaining fraction is a mix of other compounds that play crucial roles in its properties and applications.

Water

Water is the primary component of the remaining 4% in 96% ethanol, typically making up around 3 - 3.5% of the solution. Water is not just an impurity but a vital component that can influence the properties and behavior of ethanol. The presence of water in ethanol affects its solubility, boiling point, and ability to mix with other substances. In industries where water could impact sensitive processes, anhydrous alcohol (99.9%) is required, which is created through special distillation and drying processes to remove almost all water content. This anhydrous form is essential for applications that demand absolute dryness, such as in the cleaning of electronics.

Esters

Esters are another component found in small amounts (less than 1.3 g/hL) in ethanol 96%. These organic compounds are formed from the reaction between alcohols and acids. In ethanol, esters contribute to the overall sensory properties, which can be significant in industries like food and beverages, where ethanol is used as an ingredient in flavouring. Esters also influence the solvent properties of ethanol, making it suitable for dissolving a variety of compounds in, for example, paint or aerosols.

Methanol

Methanol, although present in minimal amounts, is a crucial component to consider in 96% ethanol. Methanol is a simpler alcohol that is often a byproduct of ethanol production. In non-denatured alcohol, its presence is usually kept to a maximum of 2 g/hL due to its toxicity. It is, however, a popular denaturant that is mixed with ethanol to make it unfit for human consumption and therefore exempt from excise tax. The industrial use of methanol includes being a solvent, antifreeze, and fuel. However, its inclusion in ethanol needs careful regulation, especially in applications involving human consumption or topical use.

Acetic acid

Acetic acid, the main component of vinegar, can also be found in trace amounts (less than 1.5 g/hL) in ethanol 96%. This organic acid is a byproduct of the fermentation process used to produce ethanol. Acetic acid contributes to the acidity of the ethanol solution and can affect its reactivity and stability. In industrial applications, even small amounts of acetic acid can play a role in the chemical behaviour of ethanol, influencing reactions where ethanol is used as a reagent or solvent.

Aldehydes

Aldehydes, particularly acetaldehyde, are another component of the 4% non-ethanol content, making up 0.5 g/hL of the solution. These compounds are formed during the fermentation process when sugars are converted to ethanol. Aldehydes can impart a distinct aroma and flavour to ethanol, which can be desirable or undesirable depending on the application. In the beverage industry, for instance, the presence of aldehydes needs to be carefully controlled to maintain the quality and taste of alcoholic beverages.

Why product specifications matter

Understanding the components that make up the remaining 4% of 96% ethanol provides valuable insights into its properties and applications. The presence of water, esters, methanol, acetic acid, and aldehydes highlights the complexity and versatility of this widely used chemical. While each component contributes to the overall characteristics of ethanol, their specific roles and impacts vary across different industries and applications. Therefore, it is always important to ask your ethanol supplier for the right product and request updated product specifications.

As a global supplier of ethanol in bulk, Nedstar is committed to providing high-quality ethanol solutions tailored to the specific needs of our clients. Whether you require ethanol 96% or anhydrous alcohol 99.9%, our commercial and logistical experts ensure that our products meet the highest standards of purity and performance. Ask for the specifications of the product of your choice today.