The RO Water Vs DI Water

There is no doubt that a laboratory water purifier is an important component of the lab. Because water is used in every type of experiment, ranging from small and simple experiments to complex work. All require water in enough amounts to obtain perfect results. As a lab researcher, you install a water purification system for the laboratory for obtaining the right type of pure water and in good amounts. Every lab water purification system has its extensive water purification technology which is used for the purification of tap water or normal water.

As far as the water purification technology is concerned, you check a lot of technologies and learn about it, and then approach a reliant lab water system. This process is always done to get the right water type. The water technologies do have differences between them. Widely used water purification technologies are Reverse Osmosis(RO) and Deionization Technology(DI). You can also check any water purification system for laboratory prices on the internet and offline medium. 

The major difference between the two water purification technologies is water quality.  As per the requirement of water, you can choose your lab water type from the execution of the water purification.  A laboratory water purifier is used for this purpose in the lab. The level of purity of water is all checked in the lab water system using these above techniques.

The Need Of Pure Water In Lab

A lab is a place where different kinds of techniques are executed to find good results. For obtaining reliable results, the researchers take the help of pure water. This water does not have any kind of impurities like metal ionsorganic compounds, etc.

Normal water is full of such impurities, which can interfere with the experimental results. Eventually, these impurities can make the experiment faulty that would result in complete loss. For example, if you are doing some analytical experiment in the lab, then you need pure water. The normal tap water cannot be used for this process. Many experiments and lab applications use the reverse osmosis and deionization method to produce lab water.

What Is Reverse Osmosis Water Purification Technology?

The reverse osmosis technology is called the opposite of natural process-osmosis. Here, osmosis is called the movement of water molecules across a semi-permeable membrane.  In the process of reverse osmosis, the water movement happens from a low ion concentration area to a higher ion concentration area across the semi-permeable membrane. The result of this water purification technology is called reverse osmosis water (RO water ).  It is called the type III of pure water used in the lab. 

A water purification system for laboratory use, has this purification technology to produce the RO water. In this process, the semi-permeable membrane is set up and the pressure is applied. When the pressure is applied, then the more concentrated (full of impurity) water is pushed back across the membrane.  Here, the water moves from high concentration to low concentration by leaving all impurities in the semi-permeable membrane. With this, highly purified water is obtained.  In a laboratory water purifier, the membrane is set in the chamber of the machine, and the impurity-laden water is flooded into it.

By reverse osmosis,  you can get pure water of 90-99% purity.  For some applications like buffer preparation, analyzing experiments, etc, RO water is used. The whole process of reverse osmosis is a cost-effective technology.  It does not demand high costs and maintenance.

The impurities removed with this reverse osmosis process is the following :

What Is The Deionization Water Purification Technology?

The deionization technology is known with many names like Ion exchange, polishing gear method, etc. The technology is useful in removing inorganic molecules which are present in ppb levels also. Deionization technology is excellent for removing all such impurities from the water. The normal tap water is flooded to the system in which electrodes are dipped. Here, the ion exchange happens. The positive hydrogen ions are replaced with the negative hydroxyl molecules. This way all negative ions of the impurities get replaced by positive ones, making the water clean.

Some positive chemicals like calcium can also get an exchange with the hydroxyl ions. The DI resins also help in cleaning the water in a water purification system for laboratory use. The deionization water purification technology purifies the water on demand whenever needed by the lab fellows.  Any lab water purification system uses deionization resins for purifying the water.   The resistivity of the purified water is 18.2 mega-ohm-cm.  This is the ideal resistivity for pure water.  The deionization filters also filter out the large impurities and make the water clean and good for lab applications.  However, the filters used here are not physical but can considerably purify the water.

In some purification systems, the technique is called electrodeionization technology.  The electricity is applied to the two electrodes and in between the water is put.  Here, the ion exchanges happen that make the water devoid of any impurities.  This process is called effective water purification technology as it eliminates all small impurities also.  The electrodes are opposite in charge and hence, attract the ions to themselves.  The process is built in the water purification system for laboratory use. 

The Major Difference Between The Reverse Osmosis And Deionization Purification Technology

Both types of water are used in lab applications.  They have different purposes with lab applications. Any lab water system can also produce both types of water. You can go for your required water type.  But still, the above two technologies have a major difference.  The RO water uses a semipermeable membrane to filter out the water, and the deionization uses the ion exchange method. Both are different. 

The other difference is that RO water can purify the water with an efficiency of 2 to 4 gallons and can be stored in the tank. Still, the storage can pave the way for further bacterial contamination.  For this purpose,  the RO water loses one point. While the deionization process purifies water on demand.  

In another round of difference, reverse osmosis can filter out the bacteria and viruses, but the deionization purification lacks it.  However, the DI water does not have any impurities while the RO water still contains some impurities in negligible amounts.  To a certain extent,  both the water purification technologies are used by the lab applications. 

Both the water is also good for the cleaning purpose and also eliminates the mineral deposits from water. They have great industrial applications as well as lab applications. The deionized water is said to have a complete loss of impurities, while the reverse osmosis water does have some impurities. 


The water purification system for laboratory use has both the technologies to produce the specialized water types.  It is useful in various lab experiments that require pure water.  Though the two different water types have different procedures and techniques,  still they are regarded as pure water. As a lab researcher, you can go for the one water purification technology and step up the one in your lab.

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