\n Washington, Jan 29 (ANI): A researcher is studying materials
\n that use light or darkness to purify air filled with toxins
\n that are harmful to human health and the environment.\n <\/p>\n
\n The research, conducted by Manindu Weerasinghe from Kansas State
\n University, Sri Lanka, could one day lead to filters,
\n humidifiers and other devices that can detoxify air in
\n windowless rooms, manufacturing facilities and other indoor
\n areas.\n <\/p>\n
\n \"Indoor pollutants can come from things like asbestos, markers
\n and new carpet, and are very harmful in just small amounts,\"
\n Newswise quoted Weerasinghe as saying.\n <\/p>\n
\n \"A room like an office or a laboratory that may have few or no
\n windows will have higher levels of indoor air pollutants than a room that
\n has lots of windows. Also, if the room does not have good
\n ventilation those levels would increase,\" she said.\n <\/p>\n
\n For her research, Weerasinghe is testing and analysing
\n photocatalysts and dark catalysts,
\n materials made by chemically bonding a metal to oxygen.
\n Photocatalysts react to light while dark catalysts react to
\n darkness.\n <\/p>\n
\n The photocatalysts being tested are made from chromium or
\n vanadium with titanium. Cobalt is used for the dark catalysts.
\n Finding which metal is most effective at combating pollutants
\n is key.\n <\/p>\n
\n Weerasinghe is also adding varying amounts of pure silica to
\n each catalyst mixture. Silica is the substance used to make
\n glass and ceramics and serves as an insulator in chemical
\n reactions. Based on test results, adding silica improves a
\n catalyst's ability to remove air pollutants.\n <\/p>\n
\n \"Right now it's not really clear why and how pure silica works
\n so well, so that's something I hope to also answer with more
\n experiments,\" she said.\n <\/p>\n
\n \"Glass is not toxic and silica is very abundant and
\n inexpensive, so it could be a very good material to use if this
\n work moves from laboratory-scale production to an
\n industrial-scale production,\" Weerasinghe said.\n <\/p>\n
\n Once made, each photocatalyst and dark catalyst is tested in a
\n chamber filled with air pollutants. Oxygen is added and the
\n catalyst is exposed to light or darkness, triggering a chemical
\n reaction that converts air pollutants in the chamber into
\n smaller, less harmful levels of carbon dioxide over
\n time.\n <\/p>\n
\n Although carbon dioxide is not the ideal byproduct, it is
\n produced at such small levels that it presents fewer problems
\n to health and the environment than the air pollutants,
\n Weerasinghe said.\n <\/p>\n
\n Of the photocatalysts, chromium photocatalysts reduce the most
\n air pollutants. Although the work is still in its early stages,
\n Weerasinghe is finding that the results are more complex. Tests
\n using the cobalt dark catalysts show significant gains over the
\n photocatalysts.\n <\/p>\n
\n \"In fact, the cobalt system is 10 times more active than the
\n chromium system at degrading pollutants,\" Weerasinghe said.\n <\/p>\n
\n \"It's also a rapid response system, meaning that about 10
\n minutes into the experiment the cobalt starts to react. This is
\n something that wasn't expected because these experiments are
\n about using light. But the best results are coming from a
\n system that doesn't use light to react,\" she added.\n <\/p>\n
\n In one instance, Weerasinghe tried to find the point at which
\n the dark catalyst stopped reacting. After three days into the
\n experiment no drop-off point could be found. She plans further
\n studies to investigate this unexpected phenomenon. (ANI)\n <\/p>\n<\/p>\n
See more here: Washington, Jan 29 (ANI): A researcher is studying materials that use light or darkness to purify air filled with toxins that are harmful to human health and the environment. The research, conducted by Manindu Weerasinghe from Kansas State University, Sri Lanka, could one day lead to filters, humidifiers and other devices that can detoxify air in windowless rooms, manufacturing facilities and other indoor areas. Continue reading
\nChemistry research may help free environment of toxins<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"