Studies on enzymatic biomachining of copper by glucose oxidase

Biomachining is one of the recent machining methods in which chemolithotrophic bacteria such as Acidithiobacillus ferrooxidans are used for the controlled material removal from the surfaces. In the present research, as a novel method, machining of copper was investigated by H2O2 produced in medium of biological oxidation of glucose which is catalyzed by glucose oxidase (GOx). It was shown that 0.01 g/h material removal is carried out using 100 mL solution containing FeSO4 center dot 7H(2)O 0.5 g, beta-D-(+)-glucose 1 g and GOx 100 U that incubated in the shaker-incubator for 10 h. The results of this work revealed changes of the surface morphology were negligible compared with chemical and bacterial machining and no significant disintegrity or increases of roughness was observed on the surface. Material removal rate (MRR) was about 15 times less than that of microbial material removal which indicates more controllability of the enzymatic biomachining, in the same conditions of time, copper pieces dimension, temperature and other parameters. (c) 2012 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.