Reduced Phosphorus in the Environment and Its Role in Anaerobic Iron Corrosion

Virginia Polytechnic Institute And State University, Blacksburg VA

Investigators

Abstract

0201949 Edwards Catastrophic iron corrosion sometimes occurs in the presence of SRB with profound consequences. A theory of SRB induced iron corrosion is proposed based on the observations that reduced phosphorus species such as phosphine (PH3) can catalyze the rate limiting reaction in iron corrosion, and that phosphates added to iron metal or drinking water as corrosion inhibitors can serve as the source of catalyst in the presence of sulfides. Three phases of experimental work are planned to examine aspects of reduced phosphorus species chemistry. This includes 1) development of analytical protocols and a survey of reduced P occurrence, 2) examination of the aqueous chemistry of reduced P and pathways leading to its production, and 3) defining the role of reduced phisphorus in iron corrosion. This research, although fundamental, has important applications to the engineering community. The investigators note that there is ample evidence supporting the idea that reduced phosphorus could catalyze iron corrosion under conditions present in water distribution systems. Therefore, where these forms of phosphorus are present, there can be high costs associated with pipe replacement.