Editors: | F. Kongoli, J. Antrekowitsch, T. Okura, Z. Wang, L. Liu, L. Guo, J. Ripke, E. Souza. |
Publisher: | Flogen Star OUTREACH |
Publication Year: | 2022 |
Pages: | 140 pages |
ISBN: | 978-1-989820-66-7(CD) |
ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
The inability to extract nanoparticle size of gold is one of the reasons for the high losses of valuable components with tailings during benefication of gold-bearing ores. A promising direction for the development of technologies for processing of noble raw materials is the use of various methods of physical and energy impacts on raw materials and enrichment products. Examples of such effects may be microwave [1], electric pulse [2], magnetic pulse, electrochemical, ultrasonic and other types of effects. Such research in the field of microwave treatment application was conducted in the field of auxiliary beneficiation processes (drying), ore preparation (crushing and milling) and metallurgical processing (leaching, sintering) [3-4].
Flotation experiments were carried out on Laarmann Flotation Bench Test Machine. Elemental composition analysis was carried out using Shimadzu EDX 7000 X-ray fluorescence analyzer. Determination of gold content in the sample was carried out using atomic absorption analysis, the content of organic carbon was determined on the analyzer of organic carbon TOC-L, firm Shimadzu. For microwave treatment of samples a laboratory microwave oven was used. Analysis of products after microwave treatment was carried out using MV 2300 scanning electron microscopy, CamScan and a Mastersizer 2000 particle size analyzer from Malvern Instruments.
For the investigated ores it was obtained that the main ore minerals are pyrite and arsenopyrite, barite, chalcopyrite and other minerals are present in insignificant amounts, the main rock-forming minerals are quartz, mica, carbonates and clay-sericite minerals. Contrasting surface properties of minerals with similar technological properties can be increased by applying different energy effects (MEMI, MIO, microwave, electrochemical treatment, etc.) at successive stages of raw material transformation, by regulating slurry conditioning conditions (duration and intensity of mixing, thermal treatment of slurry), as well as by developing and using selective reagent regimes. The analysis of obtained data confirms the possibility of enlarging low-dimensional noble metal particles using microwave treatment.
On the basis of conducted research, the technology of extraction of low-dimensional structures of noble and non-ferrous metals based on application of physical and energy impact methods and application of flotation methods of extraction of valuable components with a modified "carrier" was developed. It was determined that pyrite predominates in carbonaceous flotation tails, arsenic content in the tails is 0.04%. Microwave treatment of carbonaceous tailings with furnace power of 1000 W and treatment time of 12-15 minutes for enlargement of nanoparticle size of gold to the size of a few microns was substantiated.
This work was supported by the Russian Science Foundation (Рroject No. 19–17–00096).