6.5.1.5 Catalytic Removal
Now a day’s catalytic removal of toxicants from the wastewater is a promising
technology. Removal of non-biodegradable contaminants from the wastewater is
achieved in presence of a catalyst through process of oxidation, rate of enhanced
degradation. In the wastewater treatment process, oxidation of dissolved organic
carbon in liquid phase is achieved in the presence of catalysts at lower temperature
and pressure. Catalysts should be cost-effective, reliable, feasible, and have numerous active sites in its surface for improving its remediation capacity (Levec and
Pintar 2007). For catalytic activity, noble metals, e.g., platinum, ruthenium, rhodium, palladium, etc., are used for abatement of contaminants from wastewater.
Catalyst activities also depend on several factors such as wastewater pH, types and
quality of wastewater, concentration of contaminants, etc. In corrosive environment,
catalysts should be stable and mechanically strong after several run for higher
oxidation and complete mineralization of organic components (Matatov-Meytal
and Sheintuch 1998; Monteoliva et al. 2020). Yin and Zhu (2019) suggested use
of solar energy in photocatalytic oxidation technology for the treatment of the
wastewater from printing and dyeing chemical industries. Wastewater became
more hazardous due to the presence of methylene blue dye effluents. For degradation
of methylene blue dye effluents, a highly effective catalysts, Ag
+ nodes with 1,3,5trimesic acid linker by the process of hydrothermal reaction were constructed.
During the process of photocatalytic degradation, Ag
+ oxidized and become Ag
2+
and degradation mechanism completed in multistep phenomenon. At pH 3 and
20 min contact time, Ag
+ catalyst photocatalytically degrade 99.8% methylene
blue of wastewater from the printing and dying chemical industries.
6.5.1.6 Use of Nanotechnology
The availability of clean and affordable water for human need is a great challenge
during the present time. Therefore, there is need of some innovational technologies
for wastewater treatment. Nanotechnologies provide good potential for removing the
toxicants from the wastewater and create an opportunity for advanced wastewater
treatment technology. There are several properties of nanomaterials which improve
its contaminants removal capacity such as large surface area, strong sorption capacity, higher fast dissolution rate, highly reactive, super magnetism, etc. There are
some limitations of nanotechnology, e.g., higher cost, high quality of nanomaterials,
technical proficiency, etc. Collaboration between industries, research centers, government, etc., is needed for avoiding these challenges and to improve the efficiency,
reliability, and feasibility of nanotechnology (Qu et al. 2013). Hassan and Mahmood
(2019) analyzed the efficiency of iron oxide (Fe 2 O 3 ) nanoparticles for abatement of
cadmium from sewage water of Medical City, Baghdad. The best conditions for
maximum Cd removal, i.e., 96.9% are at pH 5.5, for 95.8 min contact time and with
20.77 mg/L of iron oxide nanoparticles (Hassan and Mahmood 2019).
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P. K. Singh and R. K. Sharma
Now a day’s catalytic removal of toxicants from the wastewater is a promising
technology. Removal of non-biodegradable contaminants from the wastewater is
achieved in presence of a catalyst through process of oxidation, rate of enhanced
degradation. In the wastewater treatment process, oxidation of dissolved organic
carbon in liquid phase is achieved in the presence of catalysts at lower temperature
and pressure. Catalysts should be cost-effective, reliable, feasible, and have numerous active sites in its surface for improving its remediation capacity (Levec and
Pintar 2007). For catalytic activity, noble metals, e.g., platinum, ruthenium, rhodium, palladium, etc., are used for abatement of contaminants from wastewater.
Catalyst activities also depend on several factors such as wastewater pH, types and
quality of wastewater, concentration of contaminants, etc. In corrosive environment,
catalysts should be stable and mechanically strong after several run for higher
oxidation and complete mineralization of organic components (Matatov-Meytal
and Sheintuch 1998; Monteoliva et al. 2020). Yin and Zhu (2019) suggested use
of solar energy in photocatalytic oxidation technology for the treatment of the
wastewater from printing and dyeing chemical industries. Wastewater became
more hazardous due to the presence of methylene blue dye effluents. For degradation
of methylene blue dye effluents, a highly effective catalysts, Ag
+ nodes with 1,3,5trimesic acid linker by the process of hydrothermal reaction were constructed.
During the process of photocatalytic degradation, Ag
+ oxidized and become Ag
2+
and degradation mechanism completed in multistep phenomenon. At pH 3 and
20 min contact time, Ag
+ catalyst photocatalytically degrade 99.8% methylene
blue of wastewater from the printing and dying chemical industries.
6.5.1.6 Use of Nanotechnology
The availability of clean and affordable water for human need is a great challenge
during the present time. Therefore, there is need of some innovational technologies
for wastewater treatment. Nanotechnologies provide good potential for removing the
toxicants from the wastewater and create an opportunity for advanced wastewater
treatment technology. There are several properties of nanomaterials which improve
its contaminants removal capacity such as large surface area, strong sorption capacity, higher fast dissolution rate, highly reactive, super magnetism, etc. There are
some limitations of nanotechnology, e.g., higher cost, high quality of nanomaterials,
technical proficiency, etc. Collaboration between industries, research centers, government, etc., is needed for avoiding these challenges and to improve the efficiency,
reliability, and feasibility of nanotechnology (Qu et al. 2013). Hassan and Mahmood
(2019) analyzed the efficiency of iron oxide (Fe 2 O 3 ) nanoparticles for abatement of
cadmium from sewage water of Medical City, Baghdad. The best conditions for
maximum Cd removal, i.e., 96.9% are at pH 5.5, for 95.8 min contact time and with
20.77 mg/L of iron oxide nanoparticles (Hassan and Mahmood 2019).
134
P. K. Singh and R. K. Sharma