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Acetone is a colorless flammable liquid organic compound with a distinctive odor. This is the simplest ketone, which is also often called propanone. The chemical formula is (CH3)2CO. English chemist Robert Boyle first received acetone dry distillation of potassium acetate in 1660. By the end of 1915 in British industry increased the demand for acetone. It was necessary for the production of cordite used as an explosive in artillery shells. It was so great that there was a constant lack of it. Conventional methods of production of acetone were too slow. The British Admiralty was in need of funds to facilitate the process. On May 1915, Lloyd George appointed Chaim Weizmann of the head of the Ministry of military supplies, who was a professional chemist and expert in the field of organic chemistry. He promised to help the minister in the military industry. With the bacteria Clostridium acetobutylicum, Weizmann soon realized enzymatic conversion of starch into acetone and butanol. New method for acetone allowed getting tens of thousands of tons of raw materials for the production of cordite. During the World War II this method has helped the Soviet Union to produce butadiene rubber. In present time, acetone produced primarily the so-called cumene process simultaneously with phenol from benzene and propylene through isopropylbenzene.
Acetone is widespread as various organic and salt solvent, primarily cellulose nitrate and acetate. It applies to synthesis of many important chemicals, such as acetic anhydride, definilpropan, ketene, bisphenol, isophorone, mesityl oxide and others. Acetone is widely used in the synthesis of polycarbonates, polyurethanes and epoxies. Besides, it is indispensable in the manufacture of varnishes, explosives, used to clean the surface of the paint, foam and other debris. It is used in the food and pharmaceutical industries. It is widely used in everyday life due to the relatively low toxicity. And finally, every housewife certainly uses this substance as a nail polish remover, and the owner – as paint thinner. Aceton is contained even in our body in a certain amount.
Polyethylene ([-CH2-CH2-]n) is thermoplastic polymer, which is a product of ethylene polymerization. It is translucent, chemically inert, non-plastics material with high electrical insulating properties.
Polyethylene was first invented accidentally by German engineer Hans von Perhmann in 1899. He found at the bottom of the test-tube sludge. It looked like wax. Hans had no idea of the importance of this material. This discovery has not been officially publicized. That’s why in 1933, polyethylene found a second life thanks to engineers Eric Fawcett and Reginald Gibson. Waking up one morning, they decided to experiment with high-pressure gas and noticed that one of the nodes of the machine looked as though it dipped in paraffin lubricant. Gibson’s brief notes that he had made that day in one of the laboratories of ICI in Northwich (Cheshire), ascertain the importance of the invention that he found in the flask waxy sludge. Two years later it was mass producing of polyethylene. Manufacturing telephone cable, which soon girded the world, was the first widespread use of the new polymer. During the World War II polyethylene won fame of the one of the major components needed to produce radars. Polyethylene was used as packing only in the 50s of the 20th century, when British supermarkets have begun to develop. To this day, plastic bags are incredibly common type of the packaging. Substance produced by a process called “cracking”. As a result, the manufacturer receives the product in hard and soft forms. Solid polyethylene is used for the production of fuel tanks and pipe coatings. Soft polyethylene is used in the production of casings for sausages and television cable insulation. Different containers, building materials, prosthetic organs, parts for cars and other vehicles are made of this irreplaceable material. Polyethylene applications are endless. A man uses it almost everywhere, from life to space industry.
The problem of rational use of water is one of the most important issues of our and future generations. The creation of new cities, the development of agriculture and intensive growth industries demands a big amount of fresh water. Today, it is one of the most rapidly disappearing resources on the Earth. It also is scarce and expensive. Amount of water we consume doubles every 8-10 years. The amount of contaminated water increases both. Water reserves on the Earth are great, but we use only a certain amount of it due to our geographical location. Rivers, lakes, seas, ground water, polar region and ice of alpine, the atmospheric moisture are among the most important water resources, suitable for use in various sectors of the economy. However, most often in everyday life and industry, we use fresh water from rivers, lakes and ground water. These resources account for about 2% of the total of the hydrosphere. The rest of it is enclosed in the glaciers. But we do not use most part of fresh water resources. We use only 1% of the total supply of water on the planet. Fresh water is polluted not only by industrial and domestic sewage, but oil from the recent increase in oil tanker wrecks. We urgently need to expand the territory of water usage, or we will destroy the fresh water reserves in the region. Several countries have successfully works to preserve fresh water resources. They fresh sea water, develop ways to impact on atmospheric moisture are increasingly adopting the groundwater in the service of all areas of industry. Now we hear more and more about improving production technology, in which water is treated almost to 95% or more. However, this is not ideal. The best solution of the problem of water pollution would be the establishment of closed water systems in industrial complexes. And to purify sewage we need to use biochemical methods of water purification. If each person left a minimum of waste behind, the problem would not seem so global.
Petroleum is a naturally oily flammable liquid. Petroleum as a fossil fuel is very valuable source of car energy. It is wide spread and high demanded fossil fuel in any part of the world. The main advantage of this fossil fuel is that it plays a key role in the life of the society. All car manufacture businesses are built on the engines that use the petroleum as energy. The whole development of the society in which we live now is based on the system of the transportation. It means that our way of life completely depends on the presence of the petroleum in the Earth. It also serves as a source of valuable raw materials for the production of synthetic rubber and fibers, plastics, dyes, etc. The main disadvantage of this fossil fuel is that its production, processing and consumption are the main reason of the air pollution. It has a negative impact on the Earth’s biosphere and could lead to the future problems related with concern of finite reserves of oil.
The problem with the petroleum impact on the ecosystem entailed the development of alternative fuels that make less harm and pollution. One of such alternative fuels is biodiesel. The main advantage of this fuel is that in the blend with the petroleum it creates bio fuel. This type of fuel emits less harmful elements into atmosphere. The usage of the 20% of the biodiesel in this mix does not require any modification in the engines. Biodiesel will not harm plants and animals in contact with water. It is subjected to almost complete biodegradation, which allows us to minimize the pollution of rivers and lakes. During the combustion of biodiesel it allocates exactly the same amount of carbon dioxide, which has been consumed from the atmosphere by plants for the entire period of its life. Biodiesel compared to conventional diesel fuel contains almost no sulphur. However, the production of the biodiesel leads to the biodegradation of soil and reduce its quality.
Building the power plant in the community is a stress for the local population and environment. Definitely, it is a good option for economic stability in the region, as it will bring new jobs. However, it will also bring pollution, harm to the local ecosystem and people. Choosing between nuclear plant and coal burning plant, I would prefer to see in my community the nuclear power station. A small amount of fuel is used in this type of power plant. Moreover, there is the opportunity to use it again after processing. Coal burning plant burns a day two trains of coal. Nuclear plant has higher power and low cost energy. It has an opportunity to stay in the region located far from large hydropower resources, large deposits of goals, in places where few opportunities for solar and wind power. It needs a small area to be built in the comparison with the coal burning plant. It is relatively independent from the location of raw materials. Coal burning plans does a great harm to the environment by its gas emissions to the atmosphere. The nuclear power plant makes almost no air pollution in the absence of leaks. It also does not require any railroads to transport the fuel. Of course, there are disadvantages of the nuclear power plant. Irradiated fuel is dangerous and requires complex measures for processing. The storage of the reprocessed fuel is expensive and long-lasting process. The main disadvantage of the nuclear power plant is possibility of the accident. In terms of the statistics and insurance, the major accident is highly unlikely, but the consequences of such an incident are extremely serious. The Chernobyl and recent Fucushima accidents could be examples. There are four hundred and thirty six stations in the world. All of them work with high efficiency and less harm to the environment. Unless, the alternative sources of the energy like wind, solar and wave energy are not fully developed and integrated in the world society, I would prefer nuclear power plant over coal burning plant.