Is Boiled Water the Same as Distilled Water?

by Lucy Bell-Young

While boiled water and distilled water are both involved with the liquid-gas states of H2O, they are two completely different products that are treated in very different ways.

The main difference between these two products is that boiled water is not considered purified and, therefore, cannot be used in applications where exceptionally high purity water is required. Distilled water, on the other hand, is one of the purest forms of water that is used across a range of industries. Unlike boiled water, however, distilled water isn’t recommended for consumption.

Does Boiling Water Make it Distilled?

It is true that the first step in producing distilled water is to boil it. However, this doesn’t mean that your kettle is capable of enacting the entire distillation process. The reason for this lies in the definition of ‘purified water.’

Purified water refers to water that has been mechanically processed and physically separated from its impurities. There are several purification methods, but the main three are:

  • Deionisation: this involves ion exchange resins that remove ionic impurities from the water
  • Demineralisation: this is very similar to deionisation and is used to remove mineral salts
  • Distillation: this is a separation process that purifies water by causing it to vaporise

Because distilled water has undergone a physical separation from its impurities, it is classed as having been purified. Boiled water is not processed in this way and, therefore, can’t be classified as a purified product. Therefore, if you boil water, it does not make it distilled because it does not make it pure.

Pouring boiled water into a small mug

The Difference between Boiled Water and Distilled Water

Although boiling water is a crucial step in the distillation process, these two products are not interchangeable because of their innate properties. This all comes down to the different ways each version of water is treated, which directly affects how they can be used.

Distilled Water

Distilled water is almost entirely pure. It is produced by heating water well past its boiling points so that it begins to vaporise. This vapour is then collected and condensed back into a liquid state that has had all of its impurities removed.

The separation of impurities happens because water has a lower boiling point. This means that the impurities do not vaporise with the water. This entire process is called distillation, and it is one of the most effective ways to remove things like:

  • Ionic compounds
  • Mineral salts (e.g. calcium)
  • Heavy metal salts
  • Microorganisms (e.g. bacteria)

The removal of these compounds not only means that distilled water is almost 100% pure, it also means that it is devoid of mineral nutrients like calcium, potassium and sodium. While this makes it ideally suited for use in industries like pharmaceutical manufacturing, it does not make it suitable for human consumption because it could lead to a deficiency in these essential minerals.

Boiled Water

When you think of boiled water, you immediately think of boiling the kettle for a cup of tea or for cooking. But boiled water can also be used for emergency water or surface sanitation. While it is pure enough for these applications, it cannot be used in the same industries as distilled water because it still contains mineral impurities.

Unlike distilled water, which is heated past its boiling point so that it vaporises, boiled water is only heated until it reaches its boiling point (100°C). This is a relatively quick process, unlike distillation which involves complicated steps that can take several hours.

By simply boiling water, you are able to remove organic contaminants like bacteria and germs. This is because microorganisms can’t live above 48°C. At the same time, boiling does not have an effect on other impurities like minerals, and so these remain in the water.

Therefore, while boiled water can’t be used in the ways that distilled water is used because of its mineral content, it can be consumed. In fact, boiled water will generally have a higher concentration of minerals than it did before boiling because some water will always escape as vapour.

Downward shot of water being boiled into a mug

In a nutshell…

The differences between boiled water and distilled water can be summarised in a few points:

  • Distilled water is purified via a precise distillation process that can take a few hours
  • Boiled water is simply water that has reached its boiling point, usually within a few minutes
  • Distilled water has had all of its impurities removed, including minerals and microorganisms
  • Boiled water is free from microorganisms but still contains mineral salts, like calcium
  • Distilled water is used in industrial applications where high purity water is required
  • Boiled water can be used in emergency water or surface sanitation
  • Distilled water should not be consumed because it is deficient in essential minerals
  • Boiled water has a high concentration of essential minerals and so is fine to consume

ReAgent sells high-purity distilled water in a range of pack sizes. We also supply deionised, demineralised and ultrapure water so that we can meet all of your business needs.

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