Occurrence, chlorine

Occurrence. Magnesium bromide [7789-48-2] MgBr2, is found in seawater, some mineral springs, natural brines, inland seas and lakes such as the Dead Sea and the Great Salt Lake, and salt deposits such as the Stassfurt deposits. In seawater, it is the primary source of bromine (qv). By the action of chlorine gas upon seawater or seawater bitterns, bromine is formed (see Chemicals frombrine). 

Chlorine dioxide decomposition occurrences in the generator system ate less explosive when operating under reduced pressure with water vapor... 

In an early work Kandrorand Freidlina473 suggested the occurrence of 1,3 migration of the chlorine atom from sulfur to carbon, viz.,... 

In reality, many other chemical and photochemical processes take place leading to a sort of steady-state concentration of O3 which is a sensitive function of height. To be accurate, it is necessary to include the reactions of nitrogen oxides, chlorine- and hydrogen-containing free radicals (molecules containing an unpaired electron). However, occurrence of a layer due to the altitude dependence of the photochemical processes is of fundamental geochemical importance and can be demonstrated simply by the approach of Chapman (1930). 

The occurrence of the same cis-trans isomerization observed in chlorinated hydrocarbons was finally tested for substituted c/i-stilbenes in two protic solvents, acetic acid and methanol, where the counteranion is a Br instead of a Br3". 

Bellar TA, Lichtenberg JJ, Kroner RC. 1974. The occurrence of organohalides in chlorinated drinking waters. Journal of American Water Works Association 66 703-706. 

Bruckmaim P, Kersten W, Funcke W, et al. 1988. The occurrence of chlorinated and other organic trace compounds in urban air. Chemosphere 17 2363-2380. 

Hasanen E, Soininen V, Pyysalo M, et al. 1979. The occurrence of aliphatic chlorine and bromine compound in automobile exhaust. Atmos Environ 13 1217-1219. 

Murray AJ, Riley JP. 1973. Occurrence of some chlorinated aliphatic hydrocarbons in the environment. Nature 242 37-38. 

An overview of the reactions involving trihalomethanes (haloforms) CHXYZ, where X, Y, and Z are halogen atoms, has been given in the context of ozone depletion (Hayman and Derwent 1997). Interest in the formation of trichloroacetaldehyde formed from trichloroethane and tetrachloroethene is heightened by the phytotoxicity of trichloroacetic acid (Frank et al. 1994), and by its occurrence in rainwater that seems to be a major source of this contaminant (Muller et al. 1996). The situation in Japan seems, however, to underscore the possible significance of other sources including chlorinated wastewater (Hashimoto et al. 1998). Whereas there is no doubt about the occurrence of trichloroacetic acid in rainwater (Stidson et al. 2004), its major source is unresolved since questions remain on the rate of hydrolysis of trichloroacetaldehyde (Jordan et al. 1999). 

Ahlborg UG, TM Thunberg (1980) Chlorinated phenols occurrence, toxicity, metabolism, and environmental impact. CRC CritRev Toxicol 1 1-35. 

The last reaction is the most favored of these three. The actual occurrence of the reactions with elemental phosphorus or phosphorous trichloride as products has been explained to be due to kinetic reasons. The thorium present in the ore volatilizes in the form of thorium tetrachloride (ThCl4) vapor other metallic impurities such as iron, chromium, aluminum, and titanium also form chlorides and vaporize. The product obtained after chlorination at 900 °C is virtually free from thorium chloride and phosphorous compounds, and also from the metals iron, aluminum, chromium, and titanium. 

Horii Y, Ok G, Ohura T, Kannan K (2008) Occurrence and profiles of chlorinated and brominated polycyclic aromatic hydrocarbons in waste incinerators. Environ Sci Technol 42(6) 1904—1909. doi 10.1021/es703001f... 

Shiraishi, H., N.H. Pilkington, A. Otuski, and K. Fuwa. 1985. Occurrence of chlorinated polynuclear aromatic hydrocarbons in tap water. Environ. Sci. Technol. 19 585-590. 

Very low levels are found in water and air. High levels in soils, sediments and animals. Occurrence in the environment related to chlorination degree obtained by photolysis >chlorination degree> persistence... 

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