AWWA ACE95069

The oxidation of soluble manganese (Mn(II)) to insoluble manganese dioxide (MnOx (s)) is fairly well understood; however, the role of ferric hydroxide/oxides (Fe(OH)3 (s)) in catalyzing the oxidation of Mn(II) by oxidants such as free chlorine (HOCl) is one specific aspect of manganese removal via oxidation that requires further investigation. This issue has a significant impact on the overall performance of both groundwater and surface treatment systems that practice iron and manganese removal. Literature sources indicate that bulk solution oxidation of Mn(II) by HOCl is extremely slow. Previous researchers have noted catalyzed oxidation of Mn(II) via molecular oxygen in the presence of metal oxide surfaces including iron in natural water systems, but the possible advantages this phenomenon may offer under water treatment conditions have yet to be investigated. This paper focuses on mechanistic means by which this enhanced oxidation and the data collected support the following conclusions: iron oxide surfaces play a significant role in catalyzing the oxidation of soluble manganese in solution and the reactions are highly dependent upon solution pH, HOCl concentration, and iron oxide concentration.

Product Details

Published:

01/01/1995

ISBN(s):

0898678331

Number of Pages:

16

File Size:

1 file , 560 KB