treatment. This approach can be effective for highly defined wastes or that are highly
toxic to other microorganisms. Treatment with pure cultures can be effective only if
the objective is to reduce the concentration of the target compound. Complete
mineralization may not be achieved, resulting in the accumulation of final products
and requires the addition of a second or more robust microbial community (Scott and
Ollis 1995).
5.5 Combined Adsorption and Oxidation Processes
for the Removal of Priority Pollutants
Adsorption is a simple, effective and relatively cost-effective process used for the
removal of various contaminants. However, surface phenomena that involve the
accumulation of unwanted contaminants on the solid surface end in large amounts of
“spent adsorbent” and/or “regeneration solutions”, which must be handled as “hazardous waste” (Ince and Apikyan 2000).In this way, the adsorption fulfils its
objective of removing organic and inorganic substances from an aqueous medium;
however, it does not eliminate the said compounds, but only change the medium. In
this sense, oxidative processes have been adapted for the elimination of pollutants,
since it offers an effective response to the degradation and total elimination of the
contaminants present, so to think about the combination of both processes is a
reasonable idea.
Normally the combination of adsorption-oxidation processes can be considered
as synergistic processes in which they could be taken as heterogeneous reactors
(Kurniawan and Lo 2009). The process could be considered as a catalytic reaction in
which an oxidizing agent is already mounted on the surface of the adsorbent material
(Shukla et al. 2010; Zhang et al. 2012), in other cases the adsorbent material
functions as only support to concentrate the contaminating organic substances and
then use chemical oxidizing agents and/or assisted by some physicochemical process
(Kurniawan and Lo 2009; Mok and Kim 2011). In such a way that they could be
subdivided as oxidative catalytic adsorption and adsorption assisted by an oxidative
method.
5.5.1 Oxidative Catalytic Adsorption
Most of the studies presented on oxidative catalytic adsorption consist of an adsorbent material that functions as a matrix to load some catalytic agent that triggers the
oxidative reaction. The study presented by Crittrnden-Suri shows how a material
with known characteristics as adsorbent material (Silica gel), a photoactive catalyst
(Pt-TiO 2 ) is loaded in its active sites, it was demonstrated that under controlled
laboratory tests it was possible to eliminate 96% of the organic compounds present in
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S. M. Sathianesan Vimala et al.
toxic to other microorganisms. Treatment with pure cultures can be effective only if
the objective is to reduce the concentration of the target compound. Complete
mineralization may not be achieved, resulting in the accumulation of final products
and requires the addition of a second or more robust microbial community (Scott and
Ollis 1995).
5.5 Combined Adsorption and Oxidation Processes
for the Removal of Priority Pollutants
Adsorption is a simple, effective and relatively cost-effective process used for the
removal of various contaminants. However, surface phenomena that involve the
accumulation of unwanted contaminants on the solid surface end in large amounts of
“spent adsorbent” and/or “regeneration solutions”, which must be handled as “hazardous waste” (Ince and Apikyan 2000).In this way, the adsorption fulfils its
objective of removing organic and inorganic substances from an aqueous medium;
however, it does not eliminate the said compounds, but only change the medium. In
this sense, oxidative processes have been adapted for the elimination of pollutants,
since it offers an effective response to the degradation and total elimination of the
contaminants present, so to think about the combination of both processes is a
reasonable idea.
Normally the combination of adsorption-oxidation processes can be considered
as synergistic processes in which they could be taken as heterogeneous reactors
(Kurniawan and Lo 2009). The process could be considered as a catalytic reaction in
which an oxidizing agent is already mounted on the surface of the adsorbent material
(Shukla et al. 2010; Zhang et al. 2012), in other cases the adsorbent material
functions as only support to concentrate the contaminating organic substances and
then use chemical oxidizing agents and/or assisted by some physicochemical process
(Kurniawan and Lo 2009; Mok and Kim 2011). In such a way that they could be
subdivided as oxidative catalytic adsorption and adsorption assisted by an oxidative
method.
5.5.1 Oxidative Catalytic Adsorption
Most of the studies presented on oxidative catalytic adsorption consist of an adsorbent material that functions as a matrix to load some catalytic agent that triggers the
oxidative reaction. The study presented by Crittrnden-Suri shows how a material
with known characteristics as adsorbent material (Silica gel), a photoactive catalyst
(Pt-TiO 2 ) is loaded in its active sites, it was demonstrated that under controlled
laboratory tests it was possible to eliminate 96% of the organic compounds present in
130
S. M. Sathianesan Vimala et al.