Difference Between Distilled Water and Purified Water

Main Difference – Distilled Water vs Purified Water

Water is a chemical substance that covers most areas of the earth’s crust. It is an essential component for all living organisms. Since water is one of the best solvents for most compounds to get dissolved in, water can contain many compounds as impurities. Distilled water and purified water are two forms of water that are free of impurities. These two forms have different applications according to their properties. The main difference between distilled water and purified water is that distilled water is obtained from distillation and is free from contaminants and natural minerals whereas purified water is purified from different purification methods to remove any chemicals or contaminants.

Key Areas Covered

1. What is Distilled Water
      – Definition, Production, and Uses
2. What is Purified Water
      – Definition, Production, and Uses
3. What is the Difference Between Distilled Water and Purified Water
      – Comparison of Key Differences

Key Terms: Distillation, Distilled Water, Filtration, Purification, Purified Water

What is Distilled Water

Distilled water is a form of water that is free from contaminants and natural minerals. The contaminants and other substances present in water are known as impurities. These impurities are removed by distillation when producing distilled water. The process of distillation includes boiling water followed by condensation. At the temperature that is equal to the boiling point of water, the water boils and forms steam or water vapor. Then, when steam is condensed, and water that is free from contaminants and other mineral components is produced. Since this water is obtained from distillation, it is called distilled water.

Distilled water has a number of applications in laboratory scale as well as in industries. Distilled water is safe to drink due to its purity. But the disadvantage of drinking distilled water is that it is lack of minerals that we need as nutrients. In the process of distillation, minerals remain in the bottom of the container since minerals do not boil at the boiling point of water.

Figure 1: Purified Water

However, using contaminated equipment in the process of distillation can lead to the production of impure water. Moreover, distilled water taken from an industrial source may contain contaminants. Nevertheless, distilled water from these sources is applicable for laboratory uses but not for drinking purposes.

What is Purified Water

Purified water is a form of water that is obtained from filtration methods and is free from chemicals and contaminants. Purification methods such as distillation, deionization, reverse osmosis and carbon filtration are involved in this process. The purity of purified water is measured from ppb (parts per billion) and ppt (parts per trillion) units because there are less or no contaminants in purified water.

Since distillation is also a purification method, distilled water is a type of purified water. Double distillation is used for further purification. Demineralization is a process of water purification for the removal of minerals from water. Carbon filtration is also used for the water purification. Here, water is passed through carbon, and the contaminants are adsorbed onto carbon surface.

Figure 1: Sterile Distilled Water

Purified water is used in freshwater and marine aquariums. Since this water is not composed of contaminants, fish diseases can be minimized. However, purified water is free from beneficial minerals that we require.

Difference Between Distilled Water and Purified Water

Definition

Distilled Water: Distilled water is a form of water that is free from contaminants and natural minerals.

Purified Water: Purified water is a form of water that is obtained from filtration methods and is free from chemicals and contaminants.

Method of Purification

Distilled Water: Distilled water is obtained from distillation.

Purified Water: Purified water is obtained from different purification methods such as distillation and filtration.

Cost

Distilled Water: Distilled water production requires equipment for distillation, so the cost is comparatively low.

Purified Water: Purified water production costs more than distilled water production due to advanced techniques.

Conclusion

Distilled water is a type of purified water. These terms are different from each other according to the method of purification. The main difference between distilled water and purified water is that distilled water is obtained from distillation whereas purified water can be obtained from different methods.

References:

1. “Distilled water.” Wikipedia, Wikimedia Foundation, 2 Sept. 2017,  Available here. Accessed 22 Sept. 2017.

Image Courtesy:

1. “Sterile distilled water 01” By Saltanat ebli – Own work (CC0) via Commons Wikimedia
2. “Divine Bio Purified Water” by dodongflores (CC BY 2.0) via Flickr