Distilled water production:
Firstly, tap water is filtered through macro filters to get rid of large particles.
Secondly, the water undergoes the process of reverse osmosis (reverse osmosis occurs when the water is moved across the membrane against the concentration gradient, from lower concentration to higher concentration. To illustrate, imagine a semi-permeable membrane with fresh water on one side and a concentrated aqueous solution on the other side. If normal osmosis takes place, the fresh water will cross the membrane to dilute the concentrated solution. In reverse osmosis, pressure is exerted on the side with the concentrated solution to force the water molecules across the membrane to the fresh water side.)
Thirdly, the water is then further purified using deionisation (deionisation is the removal of ions from water by exchange with other ions associated with fixed charges on a resin).
And fourthly, the water is passed through an ultraviolet light tunnel to kill any living organisms that might have escaped the first three processes. Reitzer’s Distilled Water is preservative free.