2 Natural Coagulates for Wastewater Treatment …
25
2011; Atiku et al. 2016; Rosmawanie et al. 2018). Three general phases are used to
produce the natural coagulants (Plant-based) include the primary phase (pulverizing), secondary phase (extraction) and tertiary phase (purification) (Yin 2010). In the
first phase, the unwanted and unused parts of the plants or fruits are removed while
the targeted parts usually undergo a traditional drying method then pulverizing to be
in powder form. The second and tertiary phases have been suggested to prepare the
powder formed at the first phase (pulverizing), where these powder not only contains
the coagulating active agents but also plant tissues and organic matters which may
contaminate the water rather than treat it (Ghebremichael et al. 2005). In the second
phase (extraction), the coagulating agents can be extracted from the pulverized powder using various solvents such as water, organic, and salt solution. The availability
and low cost of water make it the best option of the extraction of coagulating agents,
however, several studies have been reported that the salt solution (NaCl) is more
affected than water in extraction performance, where the results have shown that
the extracted coagulants by NaCl were more effective in coagulation activity with a
dosage estimated by 7.4 times less than the extracted coagulants by distilled water
to remove the kaolinite turbidity. Tertiary phase (purification), is usually a lab-scales
and academic researches phase due to its high cost. The previous studies have been
suggested several methods for the purification process such as lyophilization (Grossmann et al. 2018), ion-exchange (Megersa et al. 2019) and dialysis (Idris et al. 2016)
which are considered as effective methods of purification of extracts (especially for
M. oleifera) and they can be incorporated into a scaled-up set up for treatment of
higher throughput of turbid water.
2.5.1 Nirmali Seeds
S. potatorum (nirmali) is a type of tree that grows in southern central parts of India, Sri
Lanka and Burma with a moderated size. The Indian books of Sanskrit have reported
the effective use of nirmali seed to treat the turbid surface water over 4000 years
ago (Yin 2010), where it considered as the first plant-based coagulant for the water
treatment. The extracts of nirmali seed are anionic polyelectrolytes, where these
extracts work on the destabilization of particles in water by the means of interparticle bridging. The contents of the seed extracts include lipids, carbohydrates and
alkaloids containing the −COOH and free −OH surface groups which enhance the
performance of the extracts coagulation (Vijayaraghavan et al. 2011).
2.5.2 Moringa Oleifera Seed
M. oleifera (horseradish or drumstick tree) one of the tropical plants that grow in
India, Asia, Sub-Saharan Africa and Latin America. M. oleifera seed is one of the
25
2011; Atiku et al. 2016; Rosmawanie et al. 2018). Three general phases are used to
produce the natural coagulants (Plant-based) include the primary phase (pulverizing), secondary phase (extraction) and tertiary phase (purification) (Yin 2010). In the
first phase, the unwanted and unused parts of the plants or fruits are removed while
the targeted parts usually undergo a traditional drying method then pulverizing to be
in powder form. The second and tertiary phases have been suggested to prepare the
powder formed at the first phase (pulverizing), where these powder not only contains
the coagulating active agents but also plant tissues and organic matters which may
contaminate the water rather than treat it (Ghebremichael et al. 2005). In the second
phase (extraction), the coagulating agents can be extracted from the pulverized powder using various solvents such as water, organic, and salt solution. The availability
and low cost of water make it the best option of the extraction of coagulating agents,
however, several studies have been reported that the salt solution (NaCl) is more
affected than water in extraction performance, where the results have shown that
the extracted coagulants by NaCl were more effective in coagulation activity with a
dosage estimated by 7.4 times less than the extracted coagulants by distilled water
to remove the kaolinite turbidity. Tertiary phase (purification), is usually a lab-scales
and academic researches phase due to its high cost. The previous studies have been
suggested several methods for the purification process such as lyophilization (Grossmann et al. 2018), ion-exchange (Megersa et al. 2019) and dialysis (Idris et al. 2016)
which are considered as effective methods of purification of extracts (especially for
M. oleifera) and they can be incorporated into a scaled-up set up for treatment of
higher throughput of turbid water.
2.5.1 Nirmali Seeds
S. potatorum (nirmali) is a type of tree that grows in southern central parts of India, Sri
Lanka and Burma with a moderated size. The Indian books of Sanskrit have reported
the effective use of nirmali seed to treat the turbid surface water over 4000 years
ago (Yin 2010), where it considered as the first plant-based coagulant for the water
treatment. The extracts of nirmali seed are anionic polyelectrolytes, where these
extracts work on the destabilization of particles in water by the means of interparticle bridging. The contents of the seed extracts include lipids, carbohydrates and
alkaloids containing the −COOH and free −OH surface groups which enhance the
performance of the extracts coagulation (Vijayaraghavan et al. 2011).
2.5.2 Moringa Oleifera Seed
M. oleifera (horseradish or drumstick tree) one of the tropical plants that grow in
India, Asia, Sub-Saharan Africa and Latin America. M. oleifera seed is one of the