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Common Sense Emergency Response
Published in Robert A. Burke, Common Sense Emergency Response, 2020
Chlorine (elemental symbol Cl) is a nonmetallic element, a member of the halogen family of elements with an atomic number of 17 on the Periodic Table. Other halogens include fluorine, bromine, and iodine. Chlorine was discovered in 1774 by Carl Scheele, who also discovered oxygen and several other important compounds. Scheele called his discovery “dephlogisticated marine acid.” Chlorine has an atomic weight of 35.453 and is a greenish-yellow diatomic gas with a pungent irritating odor, but does not exist freely as a gas in nature. Diatomic gases are elements that do not exist as a single molecule, in this case Cl, but rather as the diatomic molecule Cl2. Other elements that are diatomic are hydrogen, nitrogen, bromine, iodine, fluorine, and oxygen. (Oxygen is often referred to as O2 because it is a diatomic element.)
Applied Chemistry and Physics
Published in Robert A. Burke, Applied Chemistry and Physics, 2020
Chlorine (elemental symbol: Cl) is a nonmetallic element, a member of the halogen family of elements with an atomic number of 17 on the periodic table. Other halogens include fluorine, bromine and iodine. Chlorine was discovered in 1774 by Carl Scheele, who also discovered oxygen and several other important compounds. Scheele called his discovery “dephlogisticated marine acid.” Chlorine has an atomic weight of 35.453 and is a greenish-yellow diatomic gas with a pungent irritating odor, but it does not exist freely as a gas in nature. Diatomic gases are elements that do not exist as a single molecule, in this case Cl, but rather as the diatomic molecule Cl2. Other elements that are diatomic are hydrogen, nitrogen, bromine, iodine, fluorine and oxygen. (Oxygen is often referred to as O2 because it is a diatomic element.)
Secondary Treatment
Published in David H.F. Liu, Béla G. Lipták, Wastewater Treatment, 2020
Chlorine is ordinarily purchased as a liquid compressed in pressurized tanks or cylinders. Small installations sometimes use solutions of sodium or calcium hypochlorite. These chemicals also ionize to produce the hypochlorite ion. for calcium hypochlorite, the following reaction occurs: Ca(OCl)2??????calciumhypochlorite→Ca2++2?OCl-
Indoor chlorine gas release in a natatorium: A case study
Published in Journal of Occupational and Environmental Hygiene, 2021
Benjamin N. Craig, Trent F. Parker, Qingsheng Wang, Michael D. Larrañaga
A release of chlorine gas occurred in a natatorium in the northeastern United States. The natatorium houses an indoor lap swimming pool, free-swimming pool, and spa and is part of a larger recreational facility. Chlorine gas (Cl2) is an irritant that primarily affects the eyes and respiratory tract (Larrañaga et al. 2016). As such, it can cause severe irritation and tissue damage, especially to the respiratory system and mucous membranes, and can lead to death at sufficiently high exposures (Wilken et al. 2017). Chlorine has a wide range of uses that range from use as an industrial chemical and precursor, a water treatment disinfectant, a bleaching agent, and a chemical warfare agent (Gupta 2015). Chlorine is a key ingredient in a wide variety of consumer products (Larrañaga et al. 2016).
Prediction of Bromate Removal in Drinking Water Using Artificial Neural Networks
Published in Ozone: Science & Engineering, 2019
Erdal Karadurmuş, Nur Taşkın, Eda Göz, Mehmet Yüceer
The increase in world population, industrial/agricultural activities threaten water resources. In parallel with this, water quality affects public health directly. The most important steps involved in domestic/drinking water treatment include removal of pathogenic microorganisms. For this purpose, disinfection has become indispensable. Disinfection with chlorine, ozone, and ultraviolet (UV) radiation have been commonly used. However, the selected disinfectant may also react with some organics and harmless microorganisms as well as pathogens, and finally, some by-products emerge (Hunter 2003; Percival et al. 2004). Bromate ion (BrO3−), trihalomethane with bromine, and acetic acid with bromine and chlorine mixtures are by-products resulting from ozonation and chlorination of drinking water. These products have carcinogenic effects. Bromate has been defined as a Group 2B carcinogen and its acceptable level is regulated as 10 µg/L by the World Health Organization (WHO) (West et al. 2015, Xiao et al. 2017a). Various adsorbent columns, anerobic bacteria, and coagulation and membrane reactors have been used to remove these by-products, but the process of adsorption appears to be the most attractive, economical, simple, and environment-friendly option (Naushad et al. 2015). Within this context, many studies on this research topic have been presented in the literature.
Recent advances on hydrometallurgical recovery of critical and precious elements from end of life electronic wastes - a review
Published in Critical Reviews in Environmental Science and Technology, 2019
Manivannan Sethurajan, Eric D. van Hullebusch, Danilo Fontana, Ata Akcil, Haci Deveci, Bojan Batinic, João P. Leal, Teresa A. Gasche, Mehmet Ali Kucuker, Kerstin Kuchta, Isabel F. F. Neto, Helena M. V. M. Soares, Andrzej Chmielarz
Chlorine was extensively used as a leaching reagent for Au extraction from ores and concentrates, even at industrial scale (Cui & Zhang, 2008; Syed, 2012). Chlorination is a practicable alternative for Au leaching due to its high dissolution rate that is achieved by controlling the redox potential. The use of chloride to leach PMs requires the presence of a strong oxidant, such as H2O2 or NaClO3. Under these conditions, Cl2 is produced, which is extremely toxic and corrosive and should be manipulated only at specific conditions and with resistant equipment. Due to these facts, chloride leaching is more difficult to apply than cyanide leaching because special stainless steel and rubber-lined equipment are required to resist to the highly corrosive acidic and oxidizing conditions. Moreover, the chlorine gas is highly poisonous and must be controlled to avoid any health risk (Syed, 2012).