Study the Process of Filtration

Our Objective

To separate solid particles from liquids and gases  


The Theory 

Filtration is the process of removing solid particles from a liquid or gaseous fluid by using a filter medium that allows the fluid to pass through but retains the solid particles. The desired product could be either the clarified fluid or the solid particles removed from the fluid. Both the fluid filtrate and the solid filter cake are recovered in some chemical manufacturing processes. Other types of media, such as electricity, light, and sound, can also be filtered. The basic requirements for filtration are as follows: (1) a filter medium; (2) a fluid containing suspended solids; (3) a driving force such as a pressure difference to cause fluid to flow; and (4) a mechanical device (the filter) that holds the filter medium, contains the fluid, and allows force to be applied. Special provisions may exist in the filter for removing the filter cake or other solid particles, washing the cake, and possibly drying the cake. The various methods for treating and removing the cake, removing the clarified filtrate, and producing the driving force on the fluid have been combined in a variety of ways to produce a wide range of filter equipment

Filtration Process in Homogeneous and Heterogeneous solution 

There are two types of mixtures: homogeneous mixtures and heterogeneous mixtures. A homogeneous mixture is one that is consistent throughout. A heterogeneous mixture is one that is not uniform throughout, i.e., the ingredients are distributed unequally. Air is a gaseous mixture that contains oxygen, nitrogen, carbon dioxide, and water vapour. 

Homogeneous mixtures are also known as solutions, especially when a solid is dissolved in a liquid. The mixture of sand and water is an example of a heterogeneous mixture. Sand remains undissolved and is distributed unevenly when shaken. A heterogeneous mixture is formed by the sand particles floating around and eventually settling to the bottom of the bottle. Filters of various types are used to purify and separate mixtures from contaminants. Filters of various pore sizes can be used, even at home, depending on the type of contaminant—large or small.

Applications of Filtration 

Filtration is also used in water treatment. Filtration can be an expensive process when it comes to water treatment and purification. Maintenance and a lack of regulation can be significant drawbacks of filtration. Furthermore, because there is no health commission or department that regulates water treatment filters, the effectiveness of filtration and purification can vary greatly between manufacturers. However, filters have enough advantages to be used as a water treatment or purification mechanism.

Practical Application of Filtration 

We filter the hot tea using a mesh filter, where milk has dissolved the juices of tea leaves and sugar that is filtered out as filtrate whereas tea dust or leaves remains as a residue. We brew coffee powder in hot water after filtering the liquid coffee is the filtrate and the large particle or coffee dust remains as a residue. 

Nowadays, vacuum cleaners with attached filters are used to soak up dust.  

Rainwater is collected and stored in a tank during rainwater harvesting. This water is pumped through several sedimentary tanks and filters before being disinfected and used for household purposes. 

Blood is constantly filtered in our kidneys through the microscopic filter, glomerulus, where essential nutrients are absorbed back, and urea is a toxic residue that is collected in the kidney and discharged out of the body. 

Many oils become fragrant and nutrient-dense by absorbing the essential oils of other flowers, fruits, and nuts. They are then filtered and used as pharmaceuticals. 

Filtration is a critical process in laboratories. Many oil-based substances dissolve in oil, and water-based substances that do not dissolve remain as residue, which can then be dissolved in water and used again. 


Learning Outcomes 

  • Students understand the term ‘filtration’ through the experiment.
  • Students understand the difference between Homogeneous and Heterogeneous solution.
  • Students are better able to perform the experiment in the real lab after experiencing it in the virtual lab.