Water
is essential for life and no creature can survive without clean and usable
water. Most water is unusable as it contains salts and many other organic and inorganic
impurities. Without taking these impurities out, the water available to us cannot
be used. Different techniques can be adapted to purify the water and make it usable.
The selection of the water purification technique can be made depending upon the
water contamination, its loading, and other parameters. Based on the
contamination and other parameters, chemical or physical techniques for water
purification can be applied. Disinfection, desalination, coagulation, and
chemical precipitation are common chemical methods used for water purification.
For adsorption, membrane filtration is used to filter the pollutant out
physically. Various char-based materials are synthesized and used for water
purification using the adsorption route. Highly porous char materials can
contain the contaminants into their pores and allow the clean water to pass
through. The overflow of the adsorbent with the pollutant can be solved by using
magnetic biochar as the contaminants can be taken out of the magnetic charbased
adsorbent and reused. Thus, the process becomes more effective and efficient. The
chapter talks about these processes and their limitations, and advantages over
the others. It also describes different types of materials used for the water
purification processes.
Keywords: Adsorption, Chemical precipitation, Coagulation, Emerging water pollutants, Filtration, Membrane filtration, Reverse osmosis, Water purification.
