Nanomaterials for Environmental Burden Reduction, Waste Treatment and Non-Point Source Pollution Control - Nanotechnologies for Water Environment Applications - page 449

Therefore, the nanomaterials industry has a tremendous opportunity to evolve as
a “green” industry, benefiting from the experience of previous industrial enterprises. The
combination of the green process and nanomaterials is a magic weapon for
environmental protection.
14.2.2 Process Emission Control

Application of nanomaterials can improve the processes to reduce formation and
emissions of industrial and agricultural wastes, including emission of ozone depleting
gases [e.g., chlorofluorocarbons (CFCs), volatile organic (chlor-containing) compounds
(VOCs)] and “greenhouse” gases (CO 2 , CH 4 , N 2 O, etc.), flue gas recovery (SO x and
NO x ), solvent vapor fractionation and solvent vapor recovery, wastewater treatment and
supply/production of drinking water, and industrial solid aerosols (Dabrowski et al.,
2001). Nanomaterials also find great potential in existing processes to convert effluents
to useful byproducts. For example, nanostructured sorbents can capture noxious gases in
an exhaust exit (Jing et al., 2006). Nanocatalysts (e.g., Green Plus) have been added to
diesel fuel, causing it to burn up more completely, and therefore, resulting in the release
of fewer CO, No x and SO x (see Table 14.2) (Fujishima et al., 2000; Booker and Boysen,
2005; Biofriendly, 2008).

Table 14.2 Petroecuador test results: buses and stationary engines.
Diesel Bus #PEJ 508 & 509

CO NO x SO x

Average Baseline (ppm) 1646.5 144.5 23.5

Average When Treated with Green Plus (ppm) 803.5 67.5 18.5

Percent Change (%) 51.20 53.29 21.28

Stationary Pump Engines 601-603 CO NO x SO x

Average Baseline (ppm) 357 572 149.5

Average When Treated with Green Plus (ppm) 174.5 294.5 72

Percent Change (%) 51.12 48.51 51.84

The nanostructured sorbent has an extremely small size and a high specific
surface area, and provides better kinetics for the adsorption of the organic pollutants and
the capture in a conventional particle control device. The combustion process is one of
the important sources to produce toxic metal emissions (Biswas and Wu, 1998). The
capture of toxic metal species in a combustion process by bulk sorbents has been
demonstrated, but the bulk sorbents have been ineffective in certain environments. The
objective of the sorbent process is to prevent eventual formation of the difficult-to-
capture submicrometer-sized particles and firmly bind the metal species to the sorbent to
prevent their leaching into our environment. Chromated copper arsenate wood
incineration air emissions and ash leaching can be controlled by using the sorbent
process (Iida et al., 2004). In-situ processing of ferroelectric materials from lead waste
streams can be controlled by injection of gas phase titanium precursors (Biswas et al.,
1998). The sorbent process is promoted by a large available specific surface area of the