What is the difference between Deionized, Distilled, and Organic Free water?

Document ID

Document ID TE6353

Published Date

Published Date 06/02/2018
Question
What is the difference between Deionized, Distilled, and Organic Free water?
Summary
Pure water types.
Answer
Distilled water goes through distillation where the water is boiled, the steam is collected in a condenser, and the condensate is collected as the finished product. All solids and most of all dissolved contaminants that have a higher boiling point then the water including minerals and other impurities like sugars are removed. There can be some impurities that are not removed, which is why distillation is often done multiple times on the same water. Any volatile organics in the water or anything else with a lower boiling point then water is not removed by distillation.

Deionized water goes through resin filters that replace any ions/minerals out of the water with H+ or OH-. This does not remove any non-ionic dissolved impurities (like sugar). The water is commonly prefiltered before it goes through the demineralizing resin to remove solids and oxidants.

Organic free water often requires that the water is treated to remove organics from the sample, and then goes through distillation and/or demineralization to remove non-organic contaminants as well as the byproducts of the organic removal pretreatment.