Metal salts Mixed layered compound

Eq. (10.12), may oxidize the dissolved SO2 to sulfate in the outer layers. The species within rectangular boxes represent the solution constituents and those in ovals represent the corrosion products. Dotted ovals represent reactions or chemical compounds for which there is no evidence by laboratory or field studies. The chemical reactions that have been described and confirmed by laboratory studies are presented as sohd arrows. The dotted arrows represent the mechanisms that are uncertain. TMI in the upper part of Fig. 10.3 stands for transition metal ions and soot catalyzes the S(IV) to S(VI). The ferrous cations react with reduced sulfur to produce several insoluble sulfides. Multistep processes including Fe(II), Fe(III), and OH produce hydroxysulfate mixed salts [5]. 

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