Chemical Processes for Inorganic Particle Formation

Some of the main aspects of the formation of inorganic particles are shown in Fignre 7.1. Of particular importance are the toxic constitnents, such as heavy metals, that may be incorporated into inorganic particles. 

FIGURE 7.1 Some of the components of inorganic particulate matter and their origins. 

Metal oxides constitute a major class of inorganic particles in the atmosphere. These are formed whenever fuels containing metals are burned. For example, particulate iron oxide is formed during the combustion of pyrite-containing coal  

Organic vanadium in residual fuel oil is converted to particulate vanadium oxide. Part of the calcium carbonate in the ash fraction of coal is converted to calcium oxide, some of which may be emitted into the atmosphere through the stack  

A common process for the formation of aerosol mists involves the oxidation of atmospheric sulfur dioxide to sulfuric acid, a hygroscopic substance that accumulates atmospheric water to form small liquid droplets  

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