EFFECT OF MICROWAVE RADIATION EXPOSURE TIME ON CHEMOLITHOTROPHS

The last two decades face a steady decline in the global reserves of free-milling high-grade ore with high content of valuable components. Incidentally, there is a rise in the commercial interest to the chemical; and bacterial leaching applicable to low-grade ore and tailings. This technology has a considerable deficiency connected with slow kinetics of redox reactions with participation of chemolithotrophs. This article presents the experimental results aimed to find optimal parameters of microwave exposure of chemolithotrophs to maximize their oxidative activity and capacity to generate ferric iron being the main oxidizer in the chemical and bacterial leaching processes. The microwave exposure tests used a microwave oven with frequency of 2.45 GHz. The power flux density was 0.7 W/cm2. The experimental results show that multiple microwave radiation exposure of chemolithotrophs for 5 s improves generation of Fe3+ ions by 27% as against the reference level. The increase in the exposure time up to 10 s has an inverse effect: proliferative capacity and oxidative activity of microorganisms decreases.


For citation: Kioresku A. V. Effect of microwave radiation exposure time on chemolithotrophs. MIAB. Mining Inf. Anal. Bull. 2019;(9):115-121. [In Russ]. DOI: 10.25018/0236-1493-2019-09-0-115-121.

Keywords

High-gradient magnetic separation, high-gradient magnetic separator, polygradient separator, collecting element, polygradient matrix, superconducting magnetic system.

Issue number: 9
Year: 2019
ISBN: 0236-1493
UDK: 66.061.34 + 622.7
DOI: 10.25018/0236-1493-2019-09-0-115-121
Authors: Kioresku A. V.

About authors: Kioresku, Graduate Student, Junior Researcher, e-mail: kioresku88@gmail.com, Scientific Research Geotechnological Center, Far Eastern Branch of Russian Academy of Science, Petropavlovsk-Kamchatsky, Russia.

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