Reverse Osmosis (RO) and Nanotechnology (Nano) are two very similar methods which are used in water filters. In appearance they are practically the same and both the methods use essentially the same technology to remove impurities from water or other liquids. In both filtration systems, Membrane Elements (or membranes, or elements) are used to separate a liquid from contaminates. Membranes are fundamentally a filter with very small “openings” that avoid contaminants from passing through when the water that is being purified is “pushed” through the membrane. Yet these two methods are very different in nature and we must understand the difference between the two to know which method provides better filtered water.
History of Reverse Osmosis & Nanotechnology
The process known as osmosis has been occurring in nature for over millions of years. But from a scientific standpoint it was first discovered in 1748 by Jean-Antoine Nollet who was a French clergyman and physicist. Soon after the discovery the study of osmosis didn’t occur till 200 years later until the late 1940s when researchers from top American universities began to reconsider the topic. The renewed interest was specifically based on a desire to find a method to filter or desalinate sea water which was the main goal. Then in 1959, two researchers from UCLA named Sidney Loeb and Srinivasa Sourirajan had successfully produced a functional synthetic RO membrane from cellulose acetate polymer.
The earliest documented application of Nanotechnology was a potable water application in Florida during the late 1970s and was potentially the first commercial, intentional use of such Nanotechnology membranes. Nanotechnology is a slightly newer technology, it has been in use for drinking water applications since the mid ’90’s and by early 2000 there were Nano membranes being used to purify drinking water.
Nanotechnology was developed principally for drinking water applications because RO water purifiers were found to remove some of the minerals in water that are considered beneficial for human consumption. Nanotechnology allows these minerals to pass through the membrane with the water, but the Nanotechnology membrane will “block” pesticides and other pollutants that can be harmful to people. Nanotechnology provides you with the best mineralised water. Although Nanotechnology was initially developed for drinking water applications, it is also becoming quite common for irrigation use. Nanotechnology is also emerging as an environmentally friendly alternative to traditional water softener systems for removing hardness from water. Giving a comparison between the two methods will surely clear any doubts.
Reverse Osmosis vs Nanotechnology
Reverse Osmosis (RO)
RO is one of the finest methods of all membrane filtration systems, with extremely small pores which are capable of removing particles as small as 0.1 nm. It has existed since the 1950s which may make it seem a bit outdated but is still used for desalination which is potable water generation from seawater or brackish water sources. Some other applications of RO involve filtering process water for industrial applications such as the printing industry, in order to sustain optimal performance of the equipment being used. RO membranes are very efficient in dispersing of all ions which could be large or small. But most companies who boast of 99% filtered or purified water through the RO process usually fail to highlight that, along with contaminants, RO removes minerals from water, stripping it of essential nutrients which are beneficial to human health. To get a clearer understanding of RO, some Pros and Cons of RO are given below.
Pros of Reverse Osmosis (RO)
· Removes most contaminants
· Lowers the TDS value of water
Cons of Reverse Osmosis (RO)
· Strips water of minerals
· Ineffective against chlorinated water
· Wastes large amounts of water
· Cannot catch many pesticides and volatiles
· Expensive Costs
Nanotechnology delivers slightly better filtration as compared to RO, with the ability to remove particles as small as 0.002 to 0.005 μm in diameter. Nanotechnology is a more up to date and reliable technology which was mainly developed for potable water generation. Nanotechnology removes hazardous contaminants, such as pesticide compounds and organic macromolecules, while retaining minerals that RO would otherwise remove. Nanotechnology membranes are capable of eliminating bigger divalent ions such as calcium sulphate, while allowing lesser monovalent ions such as sodium chloride to pass through. To get a clearer understanding of Nanotechnology, some Pros and Cons of Nanotechnology are given below.
Pros of Nanotechnology
· Retains all essential minerals
· Saves water
· Removes all contaminants (solids, microorganisms, chemicals)
· Chlorine – resistant
Cons of Nanotechnology
· Expensive Cost
Which method is better?
Depending on your water issue, both Reverse Osmosis and Nanotechnology can be used to purify water. But overall Nanotechnology is considered as the best water purification system for water purifiers as it retains all essential minerals which are fit for human consumption when an RO filter gets rid of these minerals. So next time you are purchasing a water purifier for home make sure you buy one which uses Nanotechnology.