What are Freons? Freon refer to a non-combustible gas used in conditioning appliances. They are non-flammable refrigerants based on halogenated hydrocarbon including R-12 (Dichlorodifluoromethane), R-22 (Chlorodifluoromethane) R-23 (Fluoroform). Freons are ozone depleting refrigerants that undergo evaporation process over and over again to help produce cool air that can be circulated throughout your AC.
Freons contains hydrogen, chlorine or bromine. They are odourless, non – flammable, non – corrosive gases or liquids of low toxicity. They have low boiling points, low surface tension and low viscosity.
Uses of Freons
Freon-12 or R-12 (Dichlorodifluoromethane):
Chemical Structure: CF2CI2
1. .Freon-12 (Dichlorodifluoromethane) commonly known as CFC is used as refrigerants and air conditioners.
2. They are used in aerosol spray propellants such as body spray, hair spray etc.
3. Used in liquid chillers.
4. Used in humidifiers.
5. Used in ice makers.
6. Used in water coolers.
7. Used in water fountains.
8. Used in transport refrigeration.
Properties of Freon-12
1. Freon-12 is non-toxic.
Advantages of Freon-12:
1. Freon-12 is stable:
Freon-12 does not disintegrate even under extreme operating conditions, however when it comes in contact with the flame of fire or an electrical heating equipment, it disintegrates, forming a toxic product. It is advised that we put all flames off and keep all doors open so it can escape into the atmosphere.
2. Wide range of operations:
It is used in wide range of applications like high temperature, medium temperature and low temperature applications.
3. Miscible in Oil:
Freon-12 is miscible with compressor oil under all operating conditions.
Disadvantages of Freon-12:
1. Low refrigerating effect
2. The CFC in Freon-12 has a high potential of causing depletion of the ozone layer.
Uses of R-22
1. R-22 refrigerants has been in use for years in air conditioners.
2. They are used in heat pumps.
3. They are used in mini splits.
4. They are used in car AC systems.
5. They are used in refrigerating equipments.
6. They are used in industries for liquefaction of gases.
Properties of R-22:
1. The boiling point of R-22 is -40.8°c/-41.4°F
4. Easily miscible with oil at condenser temperature, but at evaporator temperature it tends to get separated from the oil.
Advantages of R-22:
1. It has less side effect on the ozone layer.
2. Low compress displacement.
3. Greater water absorbing capacity.
Disadvantages of R-22:
It is a green house gas that contributes to the depletion of the earth’s ozone.
Chemical Structure: CHF3
Uses of R-23:
1. Used in the manufacture of Teflon.
2. Used in refrigerants.
3. Fire extinguishing agents.
4. Used in automobile conditioners.
5. Used in semi-conductor industries.
Properties of R-23:
1. It is a colorless gas.
2. It has a melting point of -155.2°C.
3. It is soluble in organic solvents.
4. It has a boiling point of -82.1°C.
Chlorofluorocarbons are non-toxic, non-flammable chemicals containing atoms of carbon, chlorine and fluorine. They are used in the manufacture of aerosol sprays, blowing agents for foam,they are used as solvents and refrigerants. They are classified as halocarbons ( a compound containing carbon and hydrogen atoms).
Examples of Chlorofluorocarbons (CFC): R11, R12, R115.
Chlorofluorocarbons are harmful to both the environment and living things. It makes green house side effect which causes harm to the ozone layer.
Sources of Chlorofluorocarbons (CFC):
1. Refrigerators and Air Conditioners.
2. Aircraft Halon.
3. Aerosol sprays.
Properties of Chlorofluorocarbons (CFC):
1. CFC is non-flammable.
2. CFC is tasteless.
3. CFC is odourless.
4. It is chemically stable.
5. It is non-toxic.
Advantages of Chlorofluorocarbons (CFC):
1. Excellent Refrigerants:
The low boiling point of CFC makes it an excellent refrigerant.
2. The low toxicity of CFC makes it a very good propellant.
3. It is useful in fire fighting.
Disadvantages of Chlorofluorocarbons (CFC):
1. It causes an increased incidence of cancer.
2. It damages the immune system.
3. It causes damage to the terrestrial and aquatic plant life.
3. Increased formation of ground level ozone.
Chlorofluorocarbons are synthetic halogenated hydrocarbon gases such as dichlorodifluoromethane (CFC-12) and chlorotrifluoroethane (CFC-13). They are widely used as refrigerants and blowing agents. They are also known for causing significant stratospheric ozone depletion and global warming.
It was found that freons increase the incidence of cardiac arrhythmias in individuals with preexisting cardiovascular disease and/or in circumstances under which adrenaline is secreted endogenously (such as anger, fear, severe exertion and stress). Further, it has been reported to be nephrotoxic resulting in renal proximal tubular damage.
Reactions of Freons
Chlorofluorocarbons or CFCs, a group of chemicals that contain carbon, chlorine, and fluorine, are used as refrigerants, fire extinguishers, local anesthetics, aerosol propellants, blowing agents for foam, chemical intermediates, and solvents. They have a low boiling and melting point and are generally colorless, non-flammable gases or liquids. They have a faint ether-like odor at high concentrations. They are a threat to the environment because they have been found to deplete the Earth’s ozone layer, which protects against harmful ultraviolet radiation.
CFCs have a very long lifetime in the troposphere and can linger for months before they reach the stratosphere, where they become vulnerable to photochemical dissociation by intense UV radiation. They lose their halogen atoms and release chlorine free radicals, which then destroy ozone molecules by a process called the ozone destruction mechanism. One chlorine molecule destroys 100,000 ozone molecules. The depletion of ozone in the upper atmosphere causes skin cancer and decreases the amount of available UV radiation that is absorbed by the oceans and clouds, damaging plant and animal life and endangering human health.
The CFCs that are released into the atmosphere can also react with hydrogen atoms in the air to form hydrofluoric acid and produce additional chlorine and fluorine. These chemicals then fall to the ground and can be washed into waterways or into the seas. The acid from these chemicals can damage the surface of the ocean and kill fish. It can also contaminate drinking water, making it dangerous to eat.
One of the main reasons for the depletion of ozone is that Freons and other chlorofluorocarbon pollutants in the upper atmosphere cause it to disappear. Ozone acts as a shield against harmful ultraviolet radiation, protecting both humans and animals. The pollution from these chemicals, however, is creating too much ozone below the protective layer, leaving too little above.
The production of ozone-depleting chemicals has been banned worldwide, but the CFCs that are already in the air will take years to disperse. It is important to reduce the use of these products and look for alternatives that will not harm the environment. The best way to do this is to purchase appliances and equipment that are certified as green.
Toxicity of Freons
Chlorofluorocarbons, also known as Freons, are a group of colorless liquids or gases that are used as refrigerants. They can also be found as aerosol propellants and degreasing solvents. Unlike most chemicals, they are non-flammable and do not react with water or any other chemical. These properties make them useful as industrial coolants and as a substitute for refrigerant oils. They also evaporate quickly. These compounds are used as refrigerants in many different industries.
While chlorofluorocarbons have a number of practical applications, they also have harmful effects on the environment. They have a high ozone-depleting potential and contribute to the greenhouse effect. Ozone depletion allows more ultraviolet radiation to reach the earth’s surface. This ultraviolet radiation can cause skin cancer in humans and damage plants.
Because of this, the production of these substances has been banned in many countries around the world. They are being replaced by hydrofluorocarbons, which have a lower ozone-depleting potential and less environmental impact.
The toxicity of these compounds depends on the amount and the route of exposure. Symptoms of inhalation can include dizziness, hypoxia, and a loss of coordination and concentration. They can also irritate the eyes, and direct contact with them can lead to frostbite.
Inhalation of freons is the most common form of exposure, but it can also be absorbed through the skin or swallowed. It is important to increase workplace safety and provide workers with adequate training and protective equipment. Occupational exposure should be limited as much as possible, and workers should wear masks or protective clothing when handling Freons.
Inhaling a large quantity of Freons can cause a range of symptoms, including headaches and dizziness. In severe cases, it can even be fatal. The best way to avoid this is to use an air-conditioning unit with a high-efficiency particulate air filter, and to wear a face mask when working with the substance.
Excessive Vaporization of Freons
In 1928, a team of chemists working at Frigidaire created dichlorodifluoromethane (known as freon) to replace the toxic gases used in refrigerators. They wanted a nontoxic, volatile compound that was less reactive and safer than ammonia or propane. They succeeded, and the gas became a popular coolant for air conditioners and refrigerators. However, it was soon discovered that these chemicals were destroying the Earth’s ozone layer and allowing dangerous ultraviolet radiation to reach the ground. As a result, they are now banned worldwide.
Chlorofluorocarbons are a group of colorless liquids and gases that are used as refrigerants, fire extinguishers, aerosol propellants, foam blowing agents, solvents, glass chillers, polymer intermediates, and heat transfer mediums. They are also known as Freons, a trademark name that refers to the most widely used fluorocarbons. These compounds are halogenated hydrocarbons that contain chlorine, fluorine, and carbon. They are odorless, tasteless, and inert at low concentrations.
However, at high concentrations, chlorofluorocarbons can be poisonous if inhaled. They can cause a variety of symptoms including central nervous system depression, bronchial constriction, tinnitus, coughing, asthma, and pulmonary edema. They can also irritate the eyes, skin, and respiratory tract. They are readily absorbed through inhalation and have a rapid distribution half-life. They can be absorbed via oral ingestion, but absorption is much slower than by inhalation.
CFCs and freons are also a significant contributor to the depletion of the Earth’s ozone layer. When they break down in the stratosphere, they release chlorine and liberate ozone molecules. This process removes thousands of ozone molecules from the atmosphere, allowing harmful UV radiation to pass through and reach the surface of the Earth.
Ozone depletion has serious implications for human health and the environment. It can cause skin cancer, eye damage, and cataracts, and it can also lead to autoimmune disorders, such as asthma and thyroiditis. It can also reduce crop yields and delay plant growth. The good news is that the depletion of ozone is preventable by reducing the production and use of freons and CFCs. Hydrofluorocarbons (HFCs), which do not contain chlorine, are a better alternative to CFCs and help protect the ozone layer.
Environmental Impact of Freons
Chlorofluorocarbons, or Freons (trademark), are the generic term for any of several simple fluorinated aliphatic hydrocarbons used in commerce and industry. These compounds contain carbon, chlorine and fluorine atoms, and they also may include hydrogen in place of some or all of the chlorine atoms. They are often referred to as CFCs, but the term “Freon” is most commonly associated with those compounds that have a lower boiling and melting point than similar compounds such as ethane and propane.
The photochemical dissociation of CFCs and other chlorofluorocarbons in the upper atmosphere was identified as a major cause of the apparent degrading of the Earth’s ozone layer in the mid-1970s. Ozone depletion threatens animal life on the planet because ozone absorbs ultraviolet radiation that would otherwise reach and burn skin cells. In response, the use of CFCs in aerosol spray containers was banned in the United States. By the early 1990s, accumulating evidence of ozone depletion in the polar regions had heightened worldwide public awareness of the issue, and most developed nations had banned the production of nearly all Freons by 1996.
As a group, Freons and other CFCs act as powerful greenhouse gases by trapping heat that would otherwise be radiated back into space. The resulting global warming effect can cause a wide variety of problems, including rising sea levels, droughts, stronger storms and flash floods. In addition, the ozone destruction caused by the chemicals in Freons leads to higher amounts of harmful ultraviolet radiation reaching the surface of the earth, which can lead to a wide variety of health issues in humans.
Inhaled orally ingested CFCs can cause central nervous system depression, as well as respiratory tract irritation and asthma. Ingestion of liquid CFCs can result in frostbite, and direct dermal or ocular contact with the substance can cause damage to the cornea. Pulmonary uptake of inhaled CFCs is rapid with peak blood concentrations occurring within 15 seconds and steady-state concentrations reaching after 20 minutes. Ingestion of orally ingested CFCs results in less rapid absorption with peak blood levels occurring after about 10 seconds and stabilizing after about 30 seconds.