Environmental Profile of Nano-finished Textile …
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5.5 Adsorption and Desorption
Adsorption processes are of two main types’ physical adsorption (Physisorption)
and chemical adsorption (Chemisorption) involving following forces of interactions: electrostatic interactions (ion exchange), chemical bonding or Van der Waals
attractions, [138–140]. Physisorption means weakly and non-specific adsorption to
the ENM surface, chemisorption and ion exchange involves chemical bonding or a
charged communication on the surface’s sites of available active sites. Under partially covered surfaces, dispersion may lead to the destabilization and aggregation
through bridging effects among the surface and the non-adsorbed functional groups
of the adsorbate. However, if the surface is fully occupied, stabilization of the dispersion may occur which may decrease the accumulation brought by both steric and
electrochemical interactions [141]. The material may adsorb impurities and act as
a route in the environment for their transport [142–144]. Sorption procedures may
be principally significant with respect to altering the surface physiognomies of the
product modified ENM to that of the product weathered ENM and environmentally
transformed ENM.
6 Environmental and Health Profile
6.1 Environmental Compatibility
The quantities of raw materials used and the release of nanomaterials into the environment over the entire life cycle of the textile materials are the major aspects for the
environmental compatibility of nanomaterials in textiles. On energy consumption
and raw material quantities used there are no clear statements or evidences reported
in literature. Walser et al. examined the greenhouse gas potential based on the CO 2
footprint using T-shirts as examples [145]. They concluded that the eco-toxicity of
the T-shirts increases during washing if biocidal materials are added. The study shows
that the use phase of the textile can make a significant influence to saving energy
with active biocidal elements since these textiles need fewer washing cycles, which
saves power and laundry detergents. The longer life cycle of the nanofinished textiles can be achieved through UV protection caused by nanomaterials to improve the
durability of the textiles (like awnings). Saving laundry cycles and detergents can
also achieve through self-cleaning surfaces [146]. Raw material and wastewater can
be saved by improved dyeability of textiles because it reduces the number of dyeing
and washing cycles. The nanomaterials via industrial and urban wastewater can enter
wastewater treatment plants. For nanomaterials the level of their elimination from the
water cycle with the sewage sludge must be explored in a broader way. Glover et al.
showed that silver ions that are released from silver particles into the environment
can form nanoscale silver particles under certain conditions and suggested that more
than 90% of the nanomaterials investigated ware separated via the sewage sludge
71
5.5 Adsorption and Desorption
Adsorption processes are of two main types’ physical adsorption (Physisorption)
and chemical adsorption (Chemisorption) involving following forces of interactions: electrostatic interactions (ion exchange), chemical bonding or Van der Waals
attractions, [138–140]. Physisorption means weakly and non-specific adsorption to
the ENM surface, chemisorption and ion exchange involves chemical bonding or a
charged communication on the surface’s sites of available active sites. Under partially covered surfaces, dispersion may lead to the destabilization and aggregation
through bridging effects among the surface and the non-adsorbed functional groups
of the adsorbate. However, if the surface is fully occupied, stabilization of the dispersion may occur which may decrease the accumulation brought by both steric and
electrochemical interactions [141]. The material may adsorb impurities and act as
a route in the environment for their transport [142–144]. Sorption procedures may
be principally significant with respect to altering the surface physiognomies of the
product modified ENM to that of the product weathered ENM and environmentally
transformed ENM.
6 Environmental and Health Profile
6.1 Environmental Compatibility
The quantities of raw materials used and the release of nanomaterials into the environment over the entire life cycle of the textile materials are the major aspects for the
environmental compatibility of nanomaterials in textiles. On energy consumption
and raw material quantities used there are no clear statements or evidences reported
in literature. Walser et al. examined the greenhouse gas potential based on the CO 2
footprint using T-shirts as examples [145]. They concluded that the eco-toxicity of
the T-shirts increases during washing if biocidal materials are added. The study shows
that the use phase of the textile can make a significant influence to saving energy
with active biocidal elements since these textiles need fewer washing cycles, which
saves power and laundry detergents. The longer life cycle of the nanofinished textiles can be achieved through UV protection caused by nanomaterials to improve the
durability of the textiles (like awnings). Saving laundry cycles and detergents can
also achieve through self-cleaning surfaces [146]. Raw material and wastewater can
be saved by improved dyeability of textiles because it reduces the number of dyeing
and washing cycles. The nanomaterials via industrial and urban wastewater can enter
wastewater treatment plants. For nanomaterials the level of their elimination from the
water cycle with the sewage sludge must be explored in a broader way. Glover et al.
showed that silver ions that are released from silver particles into the environment
can form nanoscale silver particles under certain conditions and suggested that more
than 90% of the nanomaterials investigated ware separated via the sewage sludge