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Organic Chemistry Nomenclature
Published in Arthur W. Hounslow, Water Quality Data, 2018
Many of the following compounds are priority pollutants or occur on the appendix IX Superfund list. The chlorofluorocarbon (CFC) is often referred to as Freon® in the United States. The Freon® number is derived by the following method:
Surface Treatments
Published in Thomas E. Carleson, Nathan A. Chipman, Chien M. Wai, Separation Techniques in Nuclear Waste Management, 2017
High-pressure Freon cleaning systems operate at pressures up to 3000 psi and are limited to removal of smearable contamination. These systems operate in a recycle mode with the Freon being filtered and reused. Freon is significantly better than water at removing contamination associated with grease and oil. With current environmental concerns and restrictions regarding CFCs, the use of Freon in future decontamination applications is doubtful. However, alternate solvents such as super critical carbon dioxide are being investigated.
Kinetic Propellant Pumps and Accessories
Published in Igor Bello, Vacuum and Ultravacuum, 2017
We should be aware of health and environmental hazard when we use liquid cooling substances and their mixtures. First of all, liquefied gases and vapors can cause severe low-temperature burns, and their contact with some materials may lead to violent reactions. Many slush mixtures used in cold traps are toxic or explosive. Precautions have to be taken with concentrated liquefied gases, particularly liquid oxygen and liquid hydrogen because of potential explosion when in contact with other materials. Any Freon substances are environmentally unfriendly because they destroy ozone.
Electron ionisation cross sections of CF3Cl and CF2Cl2 molecules
Published in Molecular Physics, 2022
Pawan Kumar Sharma, Rajeev Kumar
Chlorotrifluoromethane (CF3Cl) also named chlorofluorocarbon-13 (CFC-13), R-13 or Freon 13, is a non-flammable, non-corrosive, one of the mixed halomethanes which are man-made substances used primarily as a refrigerant but now banned by the Montreal Protocol and when released in the environment, deplete the ozone layer highly, produce global warming and has a very long atmospheric lifetime (640 years) [4]. Dichlorofluoromethane (CF2Cl2) also named chlorofluoro-halomethane-12 (CFC-12), R-12 or Freon-12, is a colourless gas that depletes the ozone layer highly and also has enough long atmospheric lifetime (100 years). High symmetry and high electronegativity of molecule CF2Cl2 (X1 A1) provide it with several important technological applications like cleaner of the chemical vapour deposition chamber, as a solvent, as an etching gas with applications in plasma processing and semiconductor industry, as a refrigerant, a foam blowing agent, an aerosol propellant and as an additive in gaseous dielectric mixtures [4,5].
A detailed study of IC engines and a novel discussion with comprehensive view of alternative fuels used in petrol and diesel engines
Published in International Journal of Ambient Energy, 2021
I. Vinoth Kanna, M. Arulprakasajothi, Sherin Eliyas
Numerous mixes have been tried for use as octane improvers in fuel. Tetraethyl lead was the essential octane improver as a rule use from 1923 to 1975. Its utilisation in engine vehicles was denied in 1995 because of its danger and antagonistic impact on exhaust systems and oxygen sensors. As of now, lead is just utilised in flying and go dirt road romping dashing fuels. Thomas Midgley (1889–1944), a mechanical designer from the General Motors Research Laboratory, found lead added substances in 1921, as delineated in (Midgley) (and) (Boyd) (1922). Midgley additionally was the innovator of Freon (F-12), a refrigerant at first created for car cooling frameworks. Freon was the most broadly utilised refrigerant on the planet until the mid-1990s when it was discouraging mined that the bright decay of Freon in the stratosphere discharges chlorine, causing consumption of the stratospheric ozone layer. The assembling of Freon in the United States was denied in 1998 (Table 2).
Evaluation and Optimization of O2 Used Ranque-Hilsch Vortex Tube Performance
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2021
With the developing technology, cooling plays an important role particularly in food, medicine and electronics sector. Freon is used in traditional cooling systems but this gas is quite harmful for environment (Bornare, Badgujar, and Natu 2015). Therefore, researchers have focused on environmental friendly cooling systems (Kandil and Abdelghany 2015). Unlike traditional air-conditioning systems, RHVT has superior features such as having simple mechanical structures, being economic and environment friendly, etc. The vortex tube which was invented by the French physician George J. Ranque in 1937, was later developed in 1947 by the German engineer Rudolf Hilsch and named with the names of these researchers (Kaya et al. 2018; Xue, Arjomandi, and Kelso 2010).