New advances in copper biomachining by iron-oxidizing bacteria. (November 2016)

• Record Type: Journal Article
• Authors: Díaz-Tena, E.; Gallastegui, G.; Hipperdinger, M.; Donati, E.R.; Ramírez, M.; Rodríguez, A.; López de Lacalle, L.N.; Elías, A.
• Is Part Of: Corrosion science. Volume 112(2016)
• Page Start: 385
• Page End: 392
• Publication Date: 2016-11
• Subjects: Copper -- Weight loss -- Microbiological corrosion -- Oxidation -- Potential parameters; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2016.08.001
• Languages: English
• ISSNs: 0010-938X

Abstract

Graphical abstract: Highlights: A regeneration period is compulsory for keeping a constant metal removed rate. Redox potential is a fast and reliable tool to control the status of the process. Cu 2+ affects biomachining efficiency, mainly in culturing and regeneration stages. Jarosite generation, which reduces Fe 3+ concentration, is avoided by keeping pH < 2. Abstract: The machining of copper contained in oxygen-free copper workpieces by extremophile bacteria has been studied. The effect of the main parameters affecting the continuity of the process and which decrease the removal rate were analysed during the incubation, biomachining and regeneration phases. The presence of copper affected the bacterial culture, while the enhancement of process performance due to the simultaneous presence of A. ferrooxidans and L. ferrooxidans was relatively limited. pH was maintained below 1.80 to avoid Fe 3+ losses in the form of jarosite precipitates. Measurement of the redox potential allowed a rapid monitoring of the process status.