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stood and appreciated by both the public and the research community. There are, of course, many established technologies that seek
to address either air or water pollution. These conventional systems
have by no means reached their limits, but the particular characteristics of nanomaterials appear to offer new ways of dealing with the
same problems by either offering the potential for greatly improved
performance in established technologies or offering entirely new
approaches.
Clean or useable water in needed quantities is remarkably hard to
find in many parts of the world. Standards vary for water that is
considered clean enough for use in a variety of circumstances, with
drinking water requiring very high standards. Water might not be
considered clean if it contains excess concentrations of contaminants from either natural or artificial sources. Excess salt content is
a problem in many situations. Natural sources include algae, silt,
or other dissolved natural particles. Artificial sources include pesticide and other chemical runoffs that have found their way into
water sources, with heavy metals being particularly problematic.
Critical understanding of the need for water purification and cleanliness dates back to the 19
th century. Terrible cholera outbreaks
decimated urban populations throughout the world. Investigators
such Dr. John Snow in the famous Broad Street Pump Outbreak in
Soho, at the time an unsanitary place of slaughterhouses, animal
droppings, and ancient cesspools beneath houses, found connections between the disease and waterborne microbes transmitted
through water obtained from the pump, thus beginning the great
movement toward clean water and the rather amazing high level
of water purity enjoyed in many countries today. Sadly, however,
not in all.
Today there are many conventional means of purifying water,
depending on its source and ultimate intended use, such as
drinking water versus industrial use. Evaporation processes are
employed, particularly to remove salts. Biochemical processes are
quite common, as are more direct chemical disinfection and decontamination treatments. Filtration systems of one type or another
are also common. These conventional methods do work, but many
are highly expensive—for example, chemical treatments, or have
limited flow-through capacities or other limitations. Nanomaterials may help improve many of these conventional processes and
offer new approaches as well. Recent forward-looking approaches
include the use of advanced filtration systems, improved catalytic
processes, and electronic processes, all of which are natural candidates for improvements via the use of nanotechnologies.
Environmental Benefits and Impacts
stood and appreciated by both the public and the research community. There are, of course, many established technologies that seek
to address either air or water pollution. These conventional systems
have by no means reached their limits, but the particular characteristics of nanomaterials appear to offer new ways of dealing with the
same problems by either offering the potential for greatly improved
performance in established technologies or offering entirely new
approaches.
Clean or useable water in needed quantities is remarkably hard to
find in many parts of the world. Standards vary for water that is
considered clean enough for use in a variety of circumstances, with
drinking water requiring very high standards. Water might not be
considered clean if it contains excess concentrations of contaminants from either natural or artificial sources. Excess salt content is
a problem in many situations. Natural sources include algae, silt,
or other dissolved natural particles. Artificial sources include pesticide and other chemical runoffs that have found their way into
water sources, with heavy metals being particularly problematic.
Critical understanding of the need for water purification and cleanliness dates back to the 19
th century. Terrible cholera outbreaks
decimated urban populations throughout the world. Investigators
such Dr. John Snow in the famous Broad Street Pump Outbreak in
Soho, at the time an unsanitary place of slaughterhouses, animal
droppings, and ancient cesspools beneath houses, found connections between the disease and waterborne microbes transmitted
through water obtained from the pump, thus beginning the great
movement toward clean water and the rather amazing high level
of water purity enjoyed in many countries today. Sadly, however,
not in all.
Today there are many conventional means of purifying water,
depending on its source and ultimate intended use, such as
drinking water versus industrial use. Evaporation processes are
employed, particularly to remove salts. Biochemical processes are
quite common, as are more direct chemical disinfection and decontamination treatments. Filtration systems of one type or another
are also common. These conventional methods do work, but many
are highly expensive—for example, chemical treatments, or have
limited flow-through capacities or other limitations. Nanomaterials may help improve many of these conventional processes and
offer new approaches as well. Recent forward-looking approaches
include the use of advanced filtration systems, improved catalytic
processes, and electronic processes, all of which are natural candidates for improvements via the use of nanotechnologies.
Environmental Benefits and Impacts