Wait a second!
More handpicked essays just for you.
More handpicked essays just for you.
Cfcs and global warming
Don’t take our word for it - see why 10 million students trust us with their essay needs.
Recommended: Cfcs and global warming
CFC
Introduction:
The organic compound Chlorofluorocarbon is known as CFC. This compound is made of chlorine fluorine and carbon only. CFC is in the group volatile organic compound. The CFC was first invented or made in 1928. The main purpose of CFC was to uses as refrigerants for refrigeration. Freon is the trade name of CFC .There are some main reasons behind the wide use of CFC. Non-toxic and flammability were the main reason. Around in 1960s the use of CFC increases among the developing nations. As the use of CFC increases it start to destroy the ozone layer. Fluorine and chlorine atom are separated in the reaction they remain stratosphere for long time and lowly destroy ozone layer. After that different other alternatives to CFC were, those alternatives were not harmful to ozone layer but they have a great influence on global warming.
There are different kinds of CFC. They arranged according to number fluorine and hydrogen. The banned CFC are CFC-11, -12, -113, -114, -115. Because these CFC has ozone depleting potential (ODP) as they are not soluble in water. CFC mainly emitted from aerosol sprays, industrial waste and refrigeration.
The Reactions of Chlorofluorocarbon
One of the key reaction of the CFCs is:
CCl3F → CCl2F. + Cl.
In this reaction one Cl atom dissociate from CCl3F in presence of light.
CFC or chlorofluorocarbon goes under dissociate reaction in ultraviolet radiation and produce dichlorodifluoromethane, a chlorine radical which is highly reactive:
The chlorine free radicals take the ozone from the atmosphere and produce highly reactive ClO and oxygen.
In the second layer of earth’s atmosphere, also known as stratosphere the ozone continuously undergoes in formation and decomposition. The oxygen free...
... middle of paper ...
...tor in lots of fields including the technological progress. CFCs is used massively in the food process, seventy five percent of the food in U.S has gone through a refrigerant that uses CFCs. CFCs is used excessively in the U.S as a research by Steed showed that twenty eight billion dollars a year is the price of the products that CFCs have been used to manufacture and produce. [Reference n.2]
Reference list
[Reference n.1] : Plummer, N.,L., & Busenburg, E. (2006, March). Use of chlorofluorocarbons in hydrology a guidebook. Retrieved from http://www-pub.iaea.org/MTCD/publications/pdf/Pub1238_web.pdf [Reference n.2] : Steed, M., J. (1989). Present uses of chlorofluorocarbons and effects due to environmental regulations. International Journal of Thermophysics, 10(3), 545-552. Available from http://link.springer.com/article/10.1007%2FBF00507977
While doing his research Molina learned that these compounds move up to the ozone and stay there. He expected the compounds to be destroy by the solar radiation. However to his surprise he formed that chlorofluorocarbons would simplify into component element when exposed to radiation. This simplify components produce a highly concentration of pure chlorine atoms. From there he already knew that the ozone layer can be destroy with chlorine.
2-butoxyethanol, a colorless liquid with a mild odor, is used in different paints, primers, and kinds of ink, along with numerous household cleaning products commonly found, to remove substances such as grease and oils. However, the usage of 2-butoxyethanol comes with risks as well. 2-butoxyethanol’s risks outweigh the rewards of it being used.
EDC and chlorine, in their vapour states, are fed into a chlorination reactor. This reactor operates at the conditions mentioned above (temperature: 400 – 450 degrees Celsius; pressure: 1 atmosphere). Chlorinated hydrocarbons that are by products from the reactor are recycled and fed back into the reactor. Chlorinated hydrocarbons and Hydrogen chloride exist in a mixture of the product stream from the chlorination reaction. Hydrogen chloride is then separated from the mixture. The chlorinated hydrocarbon stream is then neutralized and ...
Disinfection is applied in water as well as wastewater treatment as a finishing step so as to destroy pathogens but the cause of concern regarding the disinfection process is the formation of disinfection byproducts (DBPs). Natural organic matter (NOM) in water has been considered as the predominant DBP precursors. Disinfectants are powerful oxidants that oxidize the organic matter present in water forming DBPs. Chlorine, ozone, chlorine dioxide, and chloramines are the most common disinfectants used nowadays and each produces its own suite of chemical DBPs in finished drinking water (Richardson, 2003). DBPs so formed pose a threat to human health because of their potential to cause cancer and reproductive/developmental effects. Most developed nations have regulated concentration of DBPs so as to minimize exposure to potentially harmful DBPs while maintaining adequate disinfection and control of targeted
Chlorinated hydrocarbon - name it, describe its route of entry, and 1 or 2 health effects
Since January 1st 1999, it had been illegal to import products into Canada containing dichlorodifluoromethane, a chlorofluorocarbon (CFC) also described as CFC 12 or R12. In the year 1999, over 4000 of Canadian Tire’s imported fridges contained CFC. However, any fridges imported before January 1st 1999 containing CFC could still be sold until the existing supply was depleted. By April of 2000, inspectors across the country, together with the investigation Branch of Environment Canada became aware that Canadian Tire’s fridges which were retailed to the public had CFC labels. The government had then been concerned with whether or not these fridges were from before or after January 1st, 1999. On May 2nd 2000, Canadian Tire’s director of Environment, Health and Safety [Gail Bebee] assured Environment Canada’s investigator [Loraine Young], that any such fridges would be “old stock”.
Stratospheric ozone absorbs 97-99% of ultraviolet radiation. As this protective layer continues to dissentigrate, human health will suffer. One American dies every hour from skin cancer, a direct result of ozone depletion by anthropogenic chemicals, primarily CFCs, which damage the ozone layer. Alternate chemicals are now being used in the place of CFCs that will not damage statospheric ozone, and there is international recognition of the importance of developing these chemicals. The Montreal Protocol is an international treaty which limits the production of ozone depleting substances. Still, human health is at risk from the deletion of ozone, and the risk factor will continue to rise unless people and industries become more aware of the implications connected with everyday use of chemicals which destroy stratospheric ozone.
greenhouse gases emitted in its creation as well as use, and pollutants that cause acid rain, smog,
This article states that the ozone hole is diminishing. The credit for this good news is the phasing out of the ozone-depleting chemicals sponsored by the Montreal Protocol (Ozone hole diminishing, Nov). According to this article, the hole reached a peak of 25 million square kilometers, coming down from 28 in previous years since 1998 up to 2006. The article emphasizes the fact that ozone-depleting gases are still being used. The article continues by stating that according to the World Meteorological Organization, the planet will come back to pre-ozone hole conditions between 2060 and 2075 (Ozone hole diminishing, Nov).
The depletion of the ozone layer has been a trending topic after it was first discovered in 1970. The ozone layer is a portion of the earth’s stratosphere which absorbs most of the sun’s UV rays hence preventing cancer and other fatal illness to the skin. It contains high concentrations of O3 and at a constant rate is being broken down and. Since 1970, it has been discovered that about 4% of the ozone layer wears off every decade and is as a result of day-to-day human activity.
* Nitrogen Oxides are presented through the atmosphere. N2O are very powerful in the chemistry of the troposphere and the stratosphere, and they are very important in ozone production and in the destruction processes. There are a number of sources (the oxidation of N2O like lightning and fossil fuel combustion) whose contribution to NOx concentrations in the upper troposphere is not well measured.
Aoki, T., Munemori, M.. Continuous Flow of Free Chlorine in Water. Journal of Analytical Chemistry. 1983, 55, 209-212
In 1970, Crutzen first showed that nitrogen oxides produced by decaying nitrous oxide from soil-borne microbes react catalytically with ozone hastening its depletion. His findings started research on "global biogeochemical cycles" as well as the effects of supersonic transport aircraft that release nitrogen oxide into the stratosphere.2 In 1974, Molina and Rowland found that human-made chlorofluorocarbons used for making foam, cleaning fluids, refrigerants, and repellents transform into ozone-depleting agents.3 Chlorofluorocarbons stay in the atmosphere for several decades due to their long tropospheric lifetimes. These compounds are carried into the stratosphere where they undergo hundreds of catalytic cycles with ozone.4 They are broken down into chlorine atoms by ultraviolet radiation.5 Chlorine acts as the catalyst for breaking down atomic oxygen and molecular ozone into two molecules of molecular oxygen.
society today. The CFC cans used to be a serious problem to the ozone layer,