Reverse Osmosis vs. Selective Filtration – What’s the Difference?

28th September, 2017

2 different glasses of filtered water balancing on a stone

By now, most people are aware of how unsafe it is to drink contaminated tap water. The buzz surrounding water today is the same as the time when organic food was introduced. In both cases, the core concern is on keeping families healthy through uncontaminated food and water. While the market is flooded with a number of alternatives, it is important to understand which purifier does what, so that you may select what is good for you.

Reverse osmosis

In a reverse osmosis (RO) water filter system, a pressure is used to force water through a semi-pervious membrane. This membrane holds the solid contaminants on one side while the water passes through to the other end. This technology has been created in such a way that the membrane is able to remove anything that is larger than a water molecule from the water flowing through it. It uses the ion exclusion process where a group of ions surfaces from a barrier at the membrane. This lets the water molecules pass through without letting the contaminants follow suit.

This water purification system ensures the removal of fluoride, nitrate, sulfate, sodium, chloride, iron, mercury, zinc, arsenic, lead, cyanide, and other harmful contaminants. However, as these systems are very effective in removing solids from water, they may also end up removing essential minerals from the water. To address this problem, many new RO water purifiers come with a new kind of technology that allows minerals like potassium, calcium, and magnesium to be retained in the water.

Filtration technologies

There are different kinds of filtration technologies. Some of them are activated carbon filtration, catalytic carbon filtration, 0.5 micron filtration, and ion exchange filtration. Of these, the carbon filtration technology is most commonly used in water filters. Here, the contaminants are absorbed in the carbon substrate and the water is left clean and pure.

While the activated carbon traps organic chemicals, the catalytic carbon attacks chlorine and chloramines. The 0.5 micron filter stops asbestos and chlorine resistant cysts like giardia, cryptosporidium, and more. The ion exchange filter takes care of the heavy metals like mercury and lead. The best water filters use more than one filtration technology.

Now that you know the difference, get the best possible water purifier or filter for fresh, clean, and pure water.