Environmental Chemistry

 Hello readers! 

I hope you all doing well. Today we will discuss something about environmental chemistry. 

The environment is defined as consisting of five spheres: the hydrosphere, the atmo- sphere, the geosphere, the biosphere, and the anthrosphere; that is, water, air, the Earth, life, and those parts of the environment consisting of human constructs and activities. The chemistry of the environment, environmental chemistry, may be defined as the study of the sources, reactions, trans- port, effects, and fates of chemical species in the hydrosphere, the atmosphere, the geosphere, and the anthrosphere and the effects of human activities thereon. The pollutant sulfur dioxide is generated during the combustion of sulfur in coal, transported to the atmosphere with flue gas, and oxidized by chemical and photochemical processes to sulfuric acid. Sulfuric acid, in turn, falls as acidic precipitation, where it may have detrimental effects such as toxic effects on trees and other plants. Eventually, sulfuric acid is carried by stream runoff to a lake or ocean where its ultimate fate is to be stored in solution in the water or precipitated as solid sulfates.

Environmental chemistry is complicated by the continuous and variable interchange of chemical species among various environmental spheres. The sulfur in coal is taken from the geosphere, converted to gaseous sulfur dioxide by an anthrospheric process (combustion), transported and undergoes chemical reactions in the atmo- sphere, may affect plants in the biosphere, and ends up in a sink in the hydrosphere or back in the geosphere. Throughout this sequence, sulfur takes on several forms including organically bound sulfur or pyrite (FeS,) in coal, sulfur dioxide produced in the combustion of coal, sulfuric acid pro- duced by the oxidation of sulfur dioxide in the atmosphere, and sulfate salts produced from sulfuric acid when it reaches the geosphere. Throughout an environmental system there are variations in temperature, mixing, intensity of solar radiation, input of materials, and various other factors that strongly influence chemical conditions and behavior. Because of its complexity, environmental chemistry must be approached with simplified models.

Green chemistry, the practice of chemical science and technology in a nonpolluting, safe, and sustainable manner, and industrial ecology, which treats industrial systems in a manner analogous to natural ecosystems. Environmental chemistry has a strong connection to both of these disciplines. A major goal of green chemistry is to avoid environmental pollution, an endeavor that requires knowledge of environmental chemistry. The design of an integrated system of industrial ecology must consider the principles and processes of environmental chemistry. Environmental chemistry must be considered in the extraction of materials from the geosphere and other environmental spheres to provide the materials required byindustrial systems in a manner consistent with minimum environmental impact. The facilities and processes of an industrial ecology system can be sited and operated for minimal adverse environmen- tal impact if environmental chemistry is considered in their planning and operation. Environmental chemistry clearly points the way to minimize the environmental impacts of the emissions and by-product of industrial systems, and is very helpful in reaching the ultimate goal of a system of industrial ecology, which is to reduce these emissions and by-products to zero.