pollutants include (a) acidity, especially sulfur dioxide from coal-burning or crudeoil-burning power plants, (b) ammonia, (c) chemical waste, like fertilizers, (d) heavy
metals, and (e) silt or sediment (Speight 2017a; Speight 2017b). In general, inorganic
pollutant has harmful effects on the human body, as they tend to accumulate in living
organisms and cause various diseases, including cancer, damage to the nervous
system, reduced growth and development, and in extreme cases, death.
In summary, the priority organic pollutants are substances that share great
chemical stability, which prevents easily, degrade these molecules. Their danger is
serious since they are usually mutagenic and accumulate easily in the adipose tissues
of living beings. The inclusion of halogenated within the organic chains generate
greater stability to physical conditions of heat, which limits the manoeuvrability in
the physicochemical techniques of elimination of said compounds. On the other
hand, the priority inorganic pollutants are considered a priority due to their toxicity
as well as their mutagenic and recalcitrant properties; both have negative effects on
human health and environment.
5.3 Adsorption Processes for the Removal Contaminants
Present in the Water
5.3.1 Adsorption of Organic Pollutants
One of the techniques for the removal of pollutants in aqueous phase most used for
its high efficiency is adsorption. Adsorption is a phenomenon in which impurities
(adsorbates) of fluid on the surface of a material (adsorbent) including pores or
internal surface are retained by adhering. The adsorption is governed by electrostatic
and non-mechanical forces; even so, it is considered as a very fine type of filtration
(De Boer 1956). It can be caused by “physical” forces, comparable to those that are
responsible for the liquefaction of gases, or by “chemical” forces, similar to those
that act in the formation of normal chemical compounds. It is usual, therefore, to
distinguish between physical adsorption or physisorption (also called Van der Waals
adsorption, due to the nature of these physical forces of cohesion) and chemical
adsorption, or chemisorption.
Without a doubt, one of the key pieces in the successful removal of any contaminant through the adsorption process is the choice of good adsorbent material. This
must be chosen based on the characteristics of the pollutant. Information such as the
shape and size of the molecule, polarity, chemical nature, hydration, concentration,
among others, are data that will make it possible to design an effective adsorption
system. The variety of pollutants classified as the priority, it is intuited how diverse
the adsorption process of each compound can be.
Specifically, the adsorption of organic compounds is usually very simple, since
the size, molecular weight and configuration of the organic molecules allows a
greater fixation in the porous solids both in gas and liquid phase (Mok and Kim
5 Removal of Priority Water Pollutants Using Adsorption and Oxidation. . .
121
metals, and (e) silt or sediment (Speight 2017a; Speight 2017b). In general, inorganic
pollutant has harmful effects on the human body, as they tend to accumulate in living
organisms and cause various diseases, including cancer, damage to the nervous
system, reduced growth and development, and in extreme cases, death.
In summary, the priority organic pollutants are substances that share great
chemical stability, which prevents easily, degrade these molecules. Their danger is
serious since they are usually mutagenic and accumulate easily in the adipose tissues
of living beings. The inclusion of halogenated within the organic chains generate
greater stability to physical conditions of heat, which limits the manoeuvrability in
the physicochemical techniques of elimination of said compounds. On the other
hand, the priority inorganic pollutants are considered a priority due to their toxicity
as well as their mutagenic and recalcitrant properties; both have negative effects on
human health and environment.
5.3 Adsorption Processes for the Removal Contaminants
Present in the Water
5.3.1 Adsorption of Organic Pollutants
One of the techniques for the removal of pollutants in aqueous phase most used for
its high efficiency is adsorption. Adsorption is a phenomenon in which impurities
(adsorbates) of fluid on the surface of a material (adsorbent) including pores or
internal surface are retained by adhering. The adsorption is governed by electrostatic
and non-mechanical forces; even so, it is considered as a very fine type of filtration
(De Boer 1956). It can be caused by “physical” forces, comparable to those that are
responsible for the liquefaction of gases, or by “chemical” forces, similar to those
that act in the formation of normal chemical compounds. It is usual, therefore, to
distinguish between physical adsorption or physisorption (also called Van der Waals
adsorption, due to the nature of these physical forces of cohesion) and chemical
adsorption, or chemisorption.
Without a doubt, one of the key pieces in the successful removal of any contaminant through the adsorption process is the choice of good adsorbent material. This
must be chosen based on the characteristics of the pollutant. Information such as the
shape and size of the molecule, polarity, chemical nature, hydration, concentration,
among others, are data that will make it possible to design an effective adsorption
system. The variety of pollutants classified as the priority, it is intuited how diverse
the adsorption process of each compound can be.
Specifically, the adsorption of organic compounds is usually very simple, since
the size, molecular weight and configuration of the organic molecules allows a
greater fixation in the porous solids both in gas and liquid phase (Mok and Kim
5 Removal of Priority Water Pollutants Using Adsorption and Oxidation. . .
121