13.5 Perspectives
Accompanied with massive industrialization, the inevitability to meet demands for
various applications has led to unhindered production of a greater number of
chemicals and byproducts. Consequently, these chemicals and byproducts are
being let out into the environment either during the production process or as a
volatile waste, though may be in smaller concentration, thanks to the compliance
of rules enforced by environment protection agencies. However, there have been
some anomalies in the past that have led to environmental pollution on a larger scale
too, affecting both air and water quality severely. Among them, water contamination
by these chemicals albeit in smaller concentration is posing a huge threat to
environment. At the same time, there are clear guidelines for environmental risk
assessment apart from the government enforcing ban on toxic pollutants. Wide
publicity in media and awareness programs is being conducted by both state and
nongovernmental agencies, emphasizing the hazards of organic pollutants and the
need to sustain the good environment. Despite all these efforts, the goal to realize
drastic reduction both in usage of chemicals and generation of chemical wastes and
byproducts is indeed challenging. Many physical and chemical methods are being
developed to remove and degrade these organic pollutants from the water bodies. All
of these methods have their own advantages and disadvantages.
In case of adsorption process, the adsorbate gets adsorbed on the surface of the
adsorbent. Repeated use of the adsorbent is possible only if the adsorbate is removed
from the adsorbent. This again creates the disposal problem of organic pollutants.
The other drawback is that complete adsorption of organic pollutants on the adsorbent is hardly reported in literature. In the photocatalytic process, the organic
pollutant is normally converted into smaller products attributed to the catalytic
activity of photocatalyst. Generally, carbon dioxide and water are the degradation
products formed in this process. Moreover, this process generates free radicals,
which degrade the organic pollutants present in the water. Advanced oxidation
process uses a catalyst and oxidizing agents, such as H 2 O 2, for the degradation of
organic pollutants. Complete degradation is not achieved with most of the catalysts
and reagent combinations. This process leaves the oxidized products as residue in
the water. In electrochemical remediation of organic pollutant, electrical energy is
used to degrade the organic pollutants. This process requires higher investment and
continuous maintenance for efficient degradation of pollutants. Bioremediation is a
greener approach for degrading organic pollutants. Bioremediation process is highly
selective with respect to microbes used in the degradation of organic pollutants. So, a
wide range of organic pollutants cannot be treated effectively using this method.
Increased use of alternate and, yet, suitable greener chemicals rather than toxic
organic compounds in various applications is a must for sustainable development.
Government agencies must enforce stringent regulations besides ensuring such toxic
organic compounds are not released into the environment even inadvertently. Simultaneously, newer methods to study and remove these toxic organic pollutants should
be developed to holistically address this issue. The lessons should be drawn from
13 Remediation of Organic Pollutants in Water
513
Accompanied with massive industrialization, the inevitability to meet demands for
various applications has led to unhindered production of a greater number of
chemicals and byproducts. Consequently, these chemicals and byproducts are
being let out into the environment either during the production process or as a
volatile waste, though may be in smaller concentration, thanks to the compliance
of rules enforced by environment protection agencies. However, there have been
some anomalies in the past that have led to environmental pollution on a larger scale
too, affecting both air and water quality severely. Among them, water contamination
by these chemicals albeit in smaller concentration is posing a huge threat to
environment. At the same time, there are clear guidelines for environmental risk
assessment apart from the government enforcing ban on toxic pollutants. Wide
publicity in media and awareness programs is being conducted by both state and
nongovernmental agencies, emphasizing the hazards of organic pollutants and the
need to sustain the good environment. Despite all these efforts, the goal to realize
drastic reduction both in usage of chemicals and generation of chemical wastes and
byproducts is indeed challenging. Many physical and chemical methods are being
developed to remove and degrade these organic pollutants from the water bodies. All
of these methods have their own advantages and disadvantages.
In case of adsorption process, the adsorbate gets adsorbed on the surface of the
adsorbent. Repeated use of the adsorbent is possible only if the adsorbate is removed
from the adsorbent. This again creates the disposal problem of organic pollutants.
The other drawback is that complete adsorption of organic pollutants on the adsorbent is hardly reported in literature. In the photocatalytic process, the organic
pollutant is normally converted into smaller products attributed to the catalytic
activity of photocatalyst. Generally, carbon dioxide and water are the degradation
products formed in this process. Moreover, this process generates free radicals,
which degrade the organic pollutants present in the water. Advanced oxidation
process uses a catalyst and oxidizing agents, such as H 2 O 2, for the degradation of
organic pollutants. Complete degradation is not achieved with most of the catalysts
and reagent combinations. This process leaves the oxidized products as residue in
the water. In electrochemical remediation of organic pollutant, electrical energy is
used to degrade the organic pollutants. This process requires higher investment and
continuous maintenance for efficient degradation of pollutants. Bioremediation is a
greener approach for degrading organic pollutants. Bioremediation process is highly
selective with respect to microbes used in the degradation of organic pollutants. So, a
wide range of organic pollutants cannot be treated effectively using this method.
Increased use of alternate and, yet, suitable greener chemicals rather than toxic
organic compounds in various applications is a must for sustainable development.
Government agencies must enforce stringent regulations besides ensuring such toxic
organic compounds are not released into the environment even inadvertently. Simultaneously, newer methods to study and remove these toxic organic pollutants should
be developed to holistically address this issue. The lessons should be drawn from
13 Remediation of Organic Pollutants in Water
513