A sustainable process for material removal on pure copper by use of extremophile bacteria

• Published in: Journal of cleaner production Vol. 84; pp. 752 - 760
• Main Authors: Díaz-Tena, E., Rodríguez-Ezquerro, A., López de Lacalle Marcaide, L.N., Gurtubay Bustinduy, L., Elías Sáenz, A.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.12.2014
• Subjects: Acidithiobacillus ferrooxidans; Bacteria; Biomachining; CLEANING; Constants; Copper; COPPER (PURE); Extremophile bacteria; Green machining; MACHINING; MICRO ORGANISMS; Oxygen-free copper; PARAMETERS; Process parameters; SURFACE FINISH; Surgical equipment; Surgical instruments; Sustainable; Extremophile bacteria; Acidithiobacillus ferrooxidans; Sustainable; Green machining; Oxygen-free copper; Biomachining
• ISSN: 0959-6526; 1879-1786
• DOI: 10.1016/j.jclepro.2014.01.061

In the last decade, the use of high purity materials such as Oxygen-Free Copper has grown exponentially. Its use in scientific facilities, surgical equipment and high precision components defines the need for new research lines to improve processes and find more sustainable manufacturing technologies. A sustainable machining technology using a renewable natural source of tools is presented in this work. The use of bacteria as the main tools for the removal of copper has been known for many years. However, the technology is not advanced enough for industrial implementation so a thorough study was necessary. In this work, the chemical and biological aspects of the process were analyzed by studying the influence of the most significant process parameters. The main contribution of this work is that a stable and controlled removal process was achieved. This work shows the keys to obtaining constant removal rates over time and shows the importance of the bacteria concentration in the removal rate and surface finish, two aspects not previously studied. A process methodology for specific geometries that meet the geometric requirements was also presented. Thus, biomachining technology is now placed in a position to be directly assimilated by the industry. [Display omitted] •Extremophile bacteria are used for machining/engraving copper pieces.•Parameters were studied reaching an stable condition with no harmful disposal material.•The process may be applied for engraving patterns defined in digitized files.•Results show the potential of this technology and the low environment impact.