Organochloride

Organochlorine compounds (or chlorine compounds, precise chlorofluorocarbons ) are a group of substances of organic compounds and a subset of the halocarbons. These chemical substances have a hydrocarbon backbone wherein one or more hydrogen atoms are replaced by chlorine. Their chemical properties make it almost indispensable for the industry, on the other hand they have mostly a great environmentally -damaging potential.

Many pesticides, especially herbicides and insecticides that contain chlorinated organic compounds. Also in the production of plastics (such as PVC ) or as a flame retardant, they play an important role. Many substances, such as PCBs and lindane, which was regarded as extremely beneficial long and wide apply an end, were now banned again because of its demonstrated toxicity for humans and the environment. Some environmental scandals of recent decades, such compounds have played a central role, such as the PCB contamination of Krupa.

Classification and Characteristics

The many known chlorinated hydrocarbons can be divided into aliphatic and aromatic chlorinated alkanes and chloroalkenes chlorofluorocarbons. Chlorination with increasing the stability and lipophilicity ( lipid solubility ) of the substance grows. This recording is more difficult for degrading microorganisms and the need to break down the substances activation energy increases. The increased hydrophobicity ( insolubility ) of the substances also causes an accumulation in animal fat.

• Methylene chloride
• Dichloromethane
• Trichloromethane ( chloroform common name )
• Tetrachloromethane ( carbon tetrachloride ),
• Lindane ( γ -hexachlorocyclohexane ) is a cyclic representatives of Chloroalkanes.

• Vinyl chloride ( VC),
• 1,1- dichloroethene,
• Trichloroethene,
• Tetrachloroethene,
• Toxaphene.

• Chlorobenzene,
• 1,4- dichlorobenzene,
• DDT ( dichlorodiphenyltrichloroethane ).

• CS gas (2- chlorobenzylidene - malononitrile )
• TCCD ( the most toxic representative of the class of dioxins ).

These are not strictly chlorinated hydrocarbons because they contain other elements such as nitrogen or oxygen in addition to carbon, hydrogen and chlorine.

History

Chlorine compounds are produced synthetically since the 1930s. The introduction of a chlorine atom in the carbon skeleton often a reduction in the combustibility of the organic compound to result. Chlorine compounds are therefore often used as a non-flammable organic solvents, hydraulic oils and refrigerants. They are also used as synthetic precursors or pesticide use.

Natural Occurrence

For a long time it was assumed there would hardly be natural sources of chlorinated organic compounds. Through performance analysis, however, in recent years more and more evidence of how the natural organohalogenated bipyrrole Q1.

An important source of naturally formed, chlorinated aromatic compounds are wood- degrading fungi. Some fungi are, interestingly, even for de novo synthesis of glucose from Chloranisylen capable.

Meanwhile, more than 3,800 organohalogens natural origin are known. With the exception of the generated in the seas of methylene chloride and the bipyrrole Q1, the concentrations of most other compounds fall far below those of anthropogenic origin. The wide variety of naturally occurring halogenated organic compounds and their wide dissemination is certainly one reason for the degradation of anthropogenic pollutants.