Is Distilled Water Demineralized? Unpacking the Relationship

When it comes to purified forms of water, the terms “distilled” and “demineralized” are often used interchangeably. However, there are some key differences between these two types of water treatment that warrant clarification. This is why I’m here to answer the question definitively and explore the underlying principles of distillation and demineralization.

Understanding the precise relationship between distilled and demineralized water is important for both consumer knowledge and technical applications of purified water. Our goal is to provide clear explanations of both water processing methods and address the common misconception that distilled water is not demineralized.

Simply put, demineralized water takes out minerals, giving you just water, but it might still have bacteria or viruses. On the other hand, distilled water removes tiny particles, germs, and other impurities, leaving you with clean water.

What is Distilled Water?

Distilled water is water that has undergone the process of distillation to purify it from contaminants. Distillation involves boiling the water into steam and then condensing the steam back into pure liquid water in a separate container. This process effectively removes minerals, heavy metals, organics, bacteria, viruses, and salts from the original water source.

The boiling point of water is 100°C (212°F) while the boiling points of most impurities are higher. So when water is boiled, only pure H2O converts to steam while harmful substances are left behind. The steam is then cooled and condensed back into water free of virtually all impurities. The result is water of exceptional purity.

However, distillation systems for home use have practical limitations. Complete vaporization and condensation cannot remove 100% of contaminants. Residential-grade distillers also reintroduce some impurities from material contact. Still, properly distilled water achieves medically accepted purity standards for human consumption.

What is Demineralization?

Demineralization refers to the removal of dissolved minerals and salts from water. The most common demineralization methods include ion exchange, reverse osmosis, and membrane filtration. Each uses a different mechanism to separate and extract mineral ions from water by passing it through selective media.

Ion exchange filters swap mineral ions like calcium and magnesium for more acceptable ions like sodium. Reverse osmosis filters use a semipermeable membrane to filter out minerals based on particle size. Electrodialysis applies an electrical current to draw out mineral ions. All effectively reduce total dissolved solids in water to a very low level.

However, demineralization alone does not remove or inactivate all potential water contaminants. Bacteria, viruses, organics, gases, and some particles may still remain depending on the demineralization technology used. The process specifically targets dissolved inorganic minerals and salts.

Industrial demineralization is economically advantageous for high-purity water applications compared to distillation due to lower energy requirements. But home systems are typically reverse osmosis-based and achieve mineral reduction only.

Distilled vs. Demineralized Water Comparison

Now look at this table –

Parameter	Distilled Water	Demineralized Water
Purification Method	Distillation (vaporization and condensation)	Ion exchange, reverse osmosis, electrodialysis, etc.
Impurities Removed	Minerals, heavy metals, organics, bacteria, viruses, salts, silica, gases, radioisotopes	Primarily dissolved minerals and salts
Properties	Extremely low TDS; electrically non-conductive	Low TDS; can be electrically conductive
Applications	Laboratory processes, pharmaceuticals, electronics, human consumption	Industrial processes, boilers, semiconductor fabrication, agriculture

This table summarizes the key differences between the two water types. Fundamentally, distilled water undergoes comprehensive purification including 100% demineralization. In contrast, basic demineralization focuses specifically on mineral and salt removal while other contaminants may persist. For this reason, distilled water always results in complete demineralization, whereas demineralized water is not necessarily distilled.

Myth of Non-Demineralized Distilled Water

Given the above facts, the notion that distilled water is not demineralized can definitively be debunked as a myth. By definition, the distillation process comprehensively removes all dissolved minerals and salts, along with essentially all other impurities. No other byproduct of distillation exists aside from pure H2O.

Some confusion may arise from the fact that homemade distillers do not produce 100% pure water. But imperfect residential distillation does not change the underlying principles. Distillation intrinsically involves the complete vaporization of water, meaning it fundamentally cannot produce anything other than water devoid of minerals. While home distillers reintroduce some TDS, commercial and industrial distillation yield water proven as fully demineralized.

Health Effects of Drinking Distilled Water

The ultra-purity of distilled water has raised some health concerns around potentially leaching minerals from the body. However, moderate distilled water consumption is generally considered safe. For optimal mineral balance, experts recommend focusing on sufficient mineral intake from food rather than relying solely on water as the source. Interestingly, demineralized water may be prescribed in special diets to aid in reducing specific mineral absorption.

For everyday drinking purposes, non-distilled water with moderate mineral content is ideal for supporting electrolyte balance and proper hydration. But periodic distilled water intake as part of a balanced diet poses little concern for healthy individuals. Those with specific medical conditions or mineral deficiencies should exercise caution and first consult their physician regarding highly purified water.

Applications of Distilled and Demineralized Water

Here are some common applications taking advantage of the unique properties and purity provided by distilled and demineralized water:

Distilled Water Uses

Laboratory experiments and testing procedures
Pharmaceutical manufacturing
Medical sterilization

Lead acid batteries
Cosmetics and personal care products
Electronic component and semiconductor fabrication

Human consumption (drinking, cooking)

Demineralized Water Uses

Industrial processes make up water

Boiler feed water
Equipment cooling systems
Semiconductor manufacturing

Chemical processing
Pesticide and fertilizer production
Hospital dialysis

Laboratory rinsing

These examples reflect the niche applications leveraging the precise purification effects of distilled and demineralized water in various industries and consumer contexts.

Summary

In summary, distillation removes essentially all impurities from water, including 100% of dissolved minerals and salts. This makes distilled water a fundamentally demineralized form of water, despite limitations in home distillers reintroducing some TDS. Demineralization focuses specifically on reducing minerals and salts, but cannot achieve the comprehensive purification of full distillation.

I hope this breakdown has helped explain the precise relationship between distilled and demineralized water. Distillation is a special process that goes beyond basic demineralization to completely purify water. This allows for many unique applications across industries, laboratories, and even regular drinking water. The nuances between these methods of water treatment unlock the different possibilities for creating ultrapure water. Please reach out with any other questions!