adsorption, oxidation, photocatalysis, multistep coagulation, and flocculation
[30]. In the 21st century, membrane technologies have been used for water purification due to its high stability, high separation efficiency, and high selectivity. The
different types of membranes are available in the market to purify the water, namely,
microfiltration, ultrafiltration, reverse osmosis, and nanofiltration, respectively. Generally, the microfiltration membrane pore size ranges between 0.1 and 10 μm which
are mainly rejecting the small particles and microorganisms [31, 32]. The ultrafiltration membranes can filter the bacteria and soluble macromolecules such as proteins because it has smaller pores (0.01–0.1 μm) than the microfiltration membranes.
Particularly in the reverse osmosis process, the cellulose acetate membranes are
used, but it is nonporous, and, therefore, it eliminates the particles, salt ions,
organics, etc. [33] The nanofiltration membranes were often called as loose reverse
osmosis membranes, and it is porous in nature, but the pores are on the order of ten
less; they behave as both reverse osmosis and ultrafiltration membranes [34]. In
many countries peoples are using the reverse osmosis process for removing the
impurities from water, but unfortunately it reduces the number of beneficial minerals
in the drinking water. Therefore, drinking water purified by reverse osmosis process
can create heart and muscle health disorder. The microorganisms in water are usually
removed by boiling the water, but it is limited to use in all places. The microfiltration
membrane fails to eliminate the small-size viruses, while it eliminates the bacterial
pathogens. On the other hand, the nanofiltration membranes have a positive charge
which can selectively reject the viruses and bacteria. The identification of the
microorganism’s presence in the water is expensive, and practically it is impossible
to do all the time before drinking water. Recently, the polymeric membranes have
gained a great attention for water treatment due to its good thermal, mechanical, and
chemical properties [35]. There are many methods to develop the polymeric membranes such as interfacial polymerization, phase-inversion, self-assembly, stretching,
track-etching, spin coating, and electrospinning [33]. Among them, electrospinning
is one of the simple and versatile methods which can be used to produce nanofibrous
membrane for water purification [36].
4 Electrospinning Process
The world is facing serious concern in safe drinking water; the electrospinning-based
advance nanotechnology could be a promising strategy to purify the water in the near
future. Electrospinning-based nanotechnology is playing a vital role in water purification because it can be used to produces innovative structured membrane compared to conventional membrane technique [37]. Electrospun nanofibrous
membrane-based water purification can offer a high-standard water quality, viability,
low cost, and accessibility of drinking water. Purifying the contaminated water by
using electrospun nanofibrous membrane is a simple method to prevent drinking
waterborne illness. In addition, the electrospun nanofibrous membrane can provide
long-term protection, operated properly, and also remove the turbidity from the
230
E. Thangaraju and R. Muthuraj
[30]. In the 21st century, membrane technologies have been used for water purification due to its high stability, high separation efficiency, and high selectivity. The
different types of membranes are available in the market to purify the water, namely,
microfiltration, ultrafiltration, reverse osmosis, and nanofiltration, respectively. Generally, the microfiltration membrane pore size ranges between 0.1 and 10 μm which
are mainly rejecting the small particles and microorganisms [31, 32]. The ultrafiltration membranes can filter the bacteria and soluble macromolecules such as proteins because it has smaller pores (0.01–0.1 μm) than the microfiltration membranes.
Particularly in the reverse osmosis process, the cellulose acetate membranes are
used, but it is nonporous, and, therefore, it eliminates the particles, salt ions,
organics, etc. [33] The nanofiltration membranes were often called as loose reverse
osmosis membranes, and it is porous in nature, but the pores are on the order of ten
less; they behave as both reverse osmosis and ultrafiltration membranes [34]. In
many countries peoples are using the reverse osmosis process for removing the
impurities from water, but unfortunately it reduces the number of beneficial minerals
in the drinking water. Therefore, drinking water purified by reverse osmosis process
can create heart and muscle health disorder. The microorganisms in water are usually
removed by boiling the water, but it is limited to use in all places. The microfiltration
membrane fails to eliminate the small-size viruses, while it eliminates the bacterial
pathogens. On the other hand, the nanofiltration membranes have a positive charge
which can selectively reject the viruses and bacteria. The identification of the
microorganism’s presence in the water is expensive, and practically it is impossible
to do all the time before drinking water. Recently, the polymeric membranes have
gained a great attention for water treatment due to its good thermal, mechanical, and
chemical properties [35]. There are many methods to develop the polymeric membranes such as interfacial polymerization, phase-inversion, self-assembly, stretching,
track-etching, spin coating, and electrospinning [33]. Among them, electrospinning
is one of the simple and versatile methods which can be used to produce nanofibrous
membrane for water purification [36].
4 Electrospinning Process
The world is facing serious concern in safe drinking water; the electrospinning-based
advance nanotechnology could be a promising strategy to purify the water in the near
future. Electrospinning-based nanotechnology is playing a vital role in water purification because it can be used to produces innovative structured membrane compared to conventional membrane technique [37]. Electrospun nanofibrous
membrane-based water purification can offer a high-standard water quality, viability,
low cost, and accessibility of drinking water. Purifying the contaminated water by
using electrospun nanofibrous membrane is a simple method to prevent drinking
waterborne illness. In addition, the electrospun nanofibrous membrane can provide
long-term protection, operated properly, and also remove the turbidity from the
230
E. Thangaraju and R. Muthuraj