Redox control, degradation process

Cr(VI).Other remediation processes for Cr(VI) contaminated soils include H2S injection, aqueous Fe(II) injection, and the use of reduced Fe solids. Aqueous-phase Cr(VI)-Fe(II) redox reactions may be significant if Fe2+ concentrations are in equilibrium with relatively soluble, ferric hydroxide-like phases (Tokunaga et al., 2003). The overall interactions involving microbial activity, organic carbon degradation, Fe2+, and mineral surfaces control the net rates of Cr(VI) reactions in soils. 

Figure 12. Control of electron transfer reactions at semiconductor solution interfaces (a) electron transfer at a semiconductor solution interface and degradative recombination processes (b) application of charged colloid as a supporting agent of semiconductor particles (c) application of a redox functionalized polymer as a supporting matrix for stabilization of semiconductor colloids and effective trapping of conduction band electrons.

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