Selasa, 21 Juni 2011

USES OF CHLORINE

Key Facts About Chlorine

-        Approximately 2 million jobs in Europe are related to Chlorine.
-        85% of medicines are made using chlorine chemistry.
-        96% of crop protection used by farmers are based on chlorine chemistry.
-        55% of European chemical production depends on chlor-alakali products.
-        98% of Western Europe’s drinking water is made safe with the help of chlorine.


Everyday Application


          Chlorine has a huge variety of uses; as a disinfectant and purifier, in plastics and polymers, solvents, agrochemicals and pharmaceuticals, as well as an intermediate in manufacturing other substances where it is not contained in the final product.

          Chlorine is used worldwide to purify water supply as the ultimate defense against waterborne microbiological infection. Modern day cholera epidemics in Peru, China, India or Africa exemplify the devastating consequences of poor sanitation.

          Chlorine also plays a critical role in the productions of thousands of commercial products. Products reliant on chlorine’s unique properties include every household item such as bleach and disinfectant to bullet-resistant vests, computer hardware, silicon chips and automotive parts.

Raise Living Standards


          Standards of living are improved by many products which could not be made without chlorine. Key among these is PVC, the most versatile polymer available. It is durable, easy to clean, stain resistant, lightweight, corrosion resistant and needs no maintenance. Other polymers made using chlorine include:
-        flexible and rigid polyurethane
-        polycarbonates, used where strength is important.
-        Temperature-resistant, non-stick PTFE for frying pans, bakery tins and irons.
-        Polyvinylidene chloride (PVDC) resins used for their barrier coating properties, particularly in food packaging.

Many leisure activities rely on equipment using chlorine, such as vinyl swimming pool liners and soccer balls; golf bags; nylon tents and water-proof jackets; wet suits and inflatable rafts; surfboards; tennis rackets and many children’s toys.

          Chlorine is used in the manufacture if many car components, including: nylon for car seatbelts and air bags; vinyl upholstery; bumpers and mats; polyurethane seat cushions; dashboards; fan and alternator belts; hoses gaskets and seals; petrol additives; brakes and transmission fluids; and anti-freeze. In aircraft, it plays an important role through titanium in jet engines and alluminum in fuselages. Chlorinated solvents are also used as degreasing agents during manufacture of metal components for aircraft engines and car-braking systems. Around the world, chlorine also plays an important part in responding to natural disasters, decontaminating public water supplies damaged by floods, tornadoes and earthquakes.
            Virtually every part of the home benefits from chlorine chemistry. In house construction it is used: PVC window frames and plumbing pipes; insulation; paint (chlorine is commonly used to make titanium dioxide, the mon-toxic white pigment used in paints); nylon carpeting; and garden sprinkler systems. Inside the home, it is used to make a vast range of consumer products, including toiletries and cosmetics, televisions and compact discs. Because of its low flammability coupled with high solvency power, the chlorinated dry cleaning solvent, perchlotoethylene, has become the most widely used fabric and garment cleaner since it was introduced about 50 years ago.

Medical applications

Chlorine is essential in the manufacture of medicines to treat illnesses such as allergies, arthritis and diabetes.

Stop rely on chlorine
                    In hospitals, chlorine compounds help protect patients from infections through their use in cleaning, disinfection and antiseptics. Among their many benefits are the abilities to:
    Prevent bacterial contamination of patient’ burns and wounds
    Disinfect kidney dialysis machines
    Clean and disinfect work surfaces and equipment in medical labs
    Kill bacteria such as those which cause Legionnaire’s disease, and which can live in hospital water and air-conditioning system.

Medicines rely on chlorine
Here is a list of common medicines, which rely on chlorine chemistry:
    Chlorsiazepozide, tranquilizer chlorpromazine (pacifies or calms)
    Clometacin analgesic (pain-killer)
    Chlorcycclizine antihistamine (relief cold and allergy symptoms)
    Clobutinal antitussive (suppresses coughing)
    Clobenflural coronaty vasodilator (enlarges blood vessels of the heart)
    Clonazepam anticomvulsant (prevents convulsions of the heart)
    Clotdione anticoagulant (precents convulsions)
    Mitotane antineoplastic (inhibits growth and formation of tumours)
          Some 85%of pharmaceuticals contain or are manufactures) using chlorine, including products to treat Acids, allergies, arthritis, cancer, depression, diabetes, heart disease, hypertension, infections, pneumonia and ulcers. An example is the natual antibiotic vancomycin, which is the only effective in fighting hospital Staphylococcus infections, or methylene chlotide, extendicely used as a process solvent for coating tablets. Chlotine-containing compounds are alse important intermediater in the manufacture of Vitamin C.
          Through its use in PVC, chlorine alse contribytes to safety in tamper-resistant pharmaceutical and in “blister” packages, which help extend shelf life and make it easier for the patients to take the correct dose.
          One-quarter of medical devices contain chlotine. For example, chlotine-based plastics are used to make intravernous drips and blood bags, sterile tubing and pachaging, prosthetics and heart catheters. Silcer chloride is used for mammograogy and x-ray films. Chlorine is also used to make the semiconductors fot diagnistic instruments, and polystyrene coolers for organ transplants. Common salt is the basic of intravenous saline solutions.

          Chlotine is a powerful disinfectant, added in small quantities to ensure clean drinking water right up to the top.

Fighting diseases
          Clorine was first used in drinking water in the 19th century to control the spread of water-borne diseases sych as typhoid, cholera, dysentery and gastro-enteritis, which have killed people more than all wars in history. Fighting these remain vital today; the World Health Organization estinmates that more than three million people still die each year as a direct result of drinking unsafe water.
          Chlorine acts as a powerful disinfectant agent when used either on its own or as sodium hypochlorite. When added to water in minute quantities, it quichly kills bacteria and other microbes. It has the major advantage of ensuring clean water right up to the tap, whereas the actions of other sisinfectants-such as ozone, ultraviolet light and ultrafiltration-is only temporary. In addition to purifying water, chlorine helps remove tastes and odours, controls the growth of slime and algae in main pipes and storage tanks, and helps to remove unwanted nitrogen compounds fron water. Thoday, much of the world’s drinking water depends on chlorinination.

Proven life saver
          Many events testify to the importance of chlorine in water purification
In the US, annual deaths from cholera totaled 25000in 1900. In 1960, this figure has fallen to fewer than 20.
In 1991, a misinterpretation of US law resulted in a voluntary suspension by Peru’s governments of chlorination of water supplies. The resulting cholera epidemic spread to neighboring countries, causing 1 million cases of cholera and more than 10000 deaths.
 In 1986, 4000 people in Tenerife wee hospitalized due to water contamination, which followed the withdrawal of chlorine.
          Chlorine products are effective and economical as household bleach and as disinfectant to destroy and deactivate a wide range of dangerous microbes in homes, hospitals, swimming pools and spas, hotels, restaurants and other public places. A range of chlorine compounds-including ferric chlorine acid and hydrochloric acid-are used to purify wastewater and sewage.

Public safety
          In public safety, chlorine is used to make protective equipments for police, fire fighters:
    Protective helmets and face shields are made from plastics based on chlorine chemistry. Bullet-resistant glass is made from polycarbonate, which is made from chlorine as well.
    Bullet-resistant vests comprise aramid fibers, made from chlorine.
    Communications equipments such as radios, TV’s, microprocessors and computer parts are made from chlorine.
          Prevention is better than cure—avoid chlorine releases at home
          Here are three ways to avoid chlorine in and around home”
1.When using a dry, chlorine-based swimming pool sanitizer,always add the santitizer tot the pool. Never mix water into pool treatment chemicals.
2.Never mix different types of swimming pool santitizer together.
3.Never mix household chemical compounds with ammonia or acid-based household chemicals.

Extra facts
Window in the sky
          Have you ever heard about the window in the sky? There is a layer in the atmosphere, about 25km above sea level. This layer f gas helps to support life on earth. No organisms can exist without it. It is called the ozone, a form of oxygen. The ozone protects life on earth by absorbing UV radiation so that the harmful UV rays cannot reach the earth’s surface. However, industrialization by mankind in the past century has produced many chemicals which destroys ozone.ahole in th eozone layer appears above Antarctic every spring. One main culprit is chlotofluotocabons, or CFCs. This substances is released into the air by coolant fluids used in refrigerators, air-conditioners. CFCs in the air is broken up into chlorine atoms. These chlorine atoms eat up the ozone without themselves being destroyed. This means that they can go on to destroy more ozone molecules repeatedly. You would not belief it, but one Styrofoam plate is capable of destroying an area in the ozone larger than a football field!
          Too much UV radiation is harmful to our health. It causes burns, skin cancer and cataracts. UV also kills planktons, disrupting the chain and upsetting the natural environment. What will happen if man continues to release CFC into the air?

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