Sulfur aquatic environment, effect

The methods using sulfur(IV) species have some disadvantages as pH decreases, such as handling difficulties and high cost. Removal of chlorine residues with ammonia and chloro-aminines have harmful effects on aquatic environments and have other unpleasant properties, such as obnoxious odor, dechlorination odor, etc. Therefore, a method for reduction of chlorine to chloride using metallic iron in chlorine solutions has been studied by Ozdemir and Tufekci (1997). Chlorine solutions were prepared from chlorine obtained either by NaCl electrolysis or commercially. The chlorine solution in water was mixed at 20°C in a temperature-controlled bath. The experi-... 

Environmental Very toxic to aquatic organisms may cause long-term adverse effects in aquatic environment avoid release to environment Precaution Combustible a weak base that forms insol. salts with sulfuric acid can be diazotized, acetylated, alkylated hypergolic with red fuming nitric acid darkens on exposure to air and light avoid heat... 

In addition to its health effects on humans, sulfur dioxide has some important consequences for the physical and biological environment. Those effects occur because sulfur dioxide released to the atmosphere from electricity-generating plants and factories combines with moisture in the air to form sulfuric acid. Sulfuric acid then falls to earth in the form of acid rain, acid snow, or some other form of acid precipitation where it damages buildings and other structures, trees and other plant life, and fish and other aquatic organisms. Since 1995, the EPA has sponsored a variety of control programs designed to reduce the release of sulfur dioxide into the atmosphere to prevent such problems. 

The detrimental effects of acid deposition on both the aquatic and terrestrial environments in Europe and North America were documented extensively in the 1980s. As a result, sulfur (S) emission control programs were put into effect in both continents. In Canada, sulfur dioxide (SO2) emissions declined from 3.81 million tons in 1980 to 2.52 million in 1990, 1.74 million in 1996 and 1.25 million in 2000, a drop of 68% over 20 years. Over the same time period, emissions of SOj in the United States dropped from 17.3 million tons in 1980, the baseline year for the Clean Air Act amendments of 1990, to 15.7 million in 1990, and 10.6 million in 2001, a total drop over 21 years of 39% (Stoddard et al. 2003). An additional drop of 3.3 million tons by 2010 will bring the total decrease to 10 million tons or almost 60%. 

The Stockholm newspaper, Dagens Nyhetei, published an account of Oden s findings and sparked the first public awareness of the problem. In 1972, the Swedish government brought its case before the U.N. Conference on the Human Environment with a document entitled, "Air Pollution Across National Boundaries The Impact of Sulfur in Air and Precipitation." That same year, Norway launched a comprehensive eight-year study of the effects of acid rain on Norwegian forests and aquatic resources. ... 

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