Ozone depletion: who is to blame and what to do? Chapter 2by Nikolay Dagaev | 17-09-2018 19:33 |
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  Those of you who have read my previous article on the causes of ozone depletion know that this is a controversial issue. Scientists argue and put forward different versions. The perpetrators of the destruction of the ozone layer is called a spaceship, solar flares. However, the most popular hypothesis in the world is that the main cause of ozone layer destruction is a number of widely used chemicals (chlorofluorocarbons). This hypothesis was put forward in the mid-80s of the last century by American scientists and was the impetus for the adoption of the international Montreal Protocol in 1985. One of the points of the Protocol was the ban on refrigerant freon. Later, however, voices began to sound louder, arguing that this hypothesis is wrong and was sponsored by Western chemical corporations wishing to obtain a monopoly on the replacement of freon. Since I am used to consider any hypothesis comprehensively, without relying on the generally accepted opinion, I turned to a specialist in this matter. I was lucky to study at the gymnasium of the most famous and prestigious University in Russia - Lomonosov Moscow State University. It was established in 1755. MSU is in the top 100 best universities in the world. There are many professors of chemistry, PhD among my teachers. I asked a question to one of the my chemistry teachers, Antipin Roman Lvovich. He is Ph.D of chemical sciences, specialist in organic chemistry, author of more than 20 scientific publications in well-known scientific journals. We talked with him about this problem for a long time. And that's what I found out: in his view, freon did have a harmful effect on the ozone layer. CFCs are inert, odorless, and nontoxic, and have been used as refrigerants, solvents, and aerosol propellants. They are water insoluble and volatile, and readily escape into the upper atmosphere, where they are decomposed by high-energy sunlight to form radicals that destroy ozone by a radical chain mechanism. The overall result is that O3 is consumed as a reactant and O2 is formed. In this way, a small amount of CFC can destroy a large amount of O3. New alternatives to CFCs are hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) such as CH2FCF3. These compounds are decomposed by HO before they reach the stratosphere and therefore they do not take part in the radical reactions resulting in O3 destruction. I tend to believe my teacher, but I want to test this hypothesis myself when I have enough knowledge. I appreciate to Roman Lvovich for the interview and permission to use a fragment of his lecture in my article.
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