Future possible add on in Lead section: synthesis page contents for a quick overview of information in lead paragraph.
Uses edit
Malachite as a Copper ore edit
Simple methods of copper ore extraction from malachite involved thermodynamic processes such as smelting.[3] This reaction involves the addition of heat and a carbon, causing the carbonate to decompose leaving copper oxide and an additional carbon source such as coal converts the copper oxide into copper ore.[3] [4]
The basic word equation for this reaction is:
Copper carbonate + Heat --> Carbon dioxide + Copper oxide (color changes from green to black).[3][4]
Copper oxide + Carbon --> Carbon dioxide + Copper (color change from black to copper colored).[3][4]
Malachite is a low grade copper ore, however, due to increase demand for metals, more economic processing such as hydrometallurgical methods (using aqueous solutions such as sulfuric acid) are being used as it is readily soluble in dilute acids. [7][8] Sulfuric acid is the most common leaching agent for copper oxide ores like malachite and eliminates the need for smelting processes.[9]
The chemical equation for sulfuric acid leaching of copper ore from malachite is as follows:
Cu2(OH)2CO3 + 2H2SO4 --> 2CuSO4 + CO2 +3H2O[9]
Health and Environmental Concerns edit
Mining for malachite for ornamental or copper ore purposes involves open-pit mining or underground mining depending on the grade of the ore deposits[10]. Open-pit and underground mining practices can cause environmental degradation through habitat and biodiversity loss[11][12]. Acid mine drainage can contaminate water and food sources to negatively impact human health if improperly managed or if leaks from tailing ponds occur[12][13]. The risk of health and environmental impacts of both traditional metallurgy and newer methods of hydrometallurgy are both significant[12], however, water conservation and waste management practices for hydrometallurgy processes for ore extraction, such as for malachite, are stricter and relatively more sustainable[14]. New research is also being conducted on better alternatives to methods such as sulfuric acid leaching which has high environmental impacts, even under hydrometallurgy regulation standards and innovation [9].
References edit
- ^ "Malachite". mindat.org. Retrieved 2021-03-18.
- ^ "Creative Commons — Attribution-ShareAlike 3.0 Unported — CC BY-SA 3.0". creativecommons.org. Retrieved 2021-03-18.
- ^ a b c d Johnson, Cris E.; Yee, Gordon T.; Eddleton, Jeannine E. (2004-12-01). "Copper Metal from Malachite circa 4000 B.C.E." Journal of Chemical Education. 81 (12): 1777. doi:10.1021/ed081p1777. ISSN 0021-9584.
- ^ a b c Day, Jo; Kobik, Maggie (2019-09-30), "Reconstructing a Bronze Age Kiln from Priniatikos Pyrgos, Crete", Experimental Archaeology: Making, Understanding, Story-telling, Archaeopress Publishing Ltd, pp. 63–72, ISBN 978-1-78969-320-1, retrieved 2021-02-25
- ^ "Chemical Elements - Copper". images-of-elements.com. Retrieved 2021-03-18.
- ^ "Creative Commons — Attribution 3.0 Unported — CC BY 3.0". creativecommons.org. Retrieved 2021-03-18.
- ^ Ata, O. N.; Yalap, H. (2007-06-01). "Optimization of Copper Leaching from Ore Containing Malachite". Canadian Metallurgical Quarterly. 46 (2): 107–114. doi:10.1179/cmq.2007.46.2.107. ISSN 0008-4433.
- ^ "Malachite". www.mindat.org. Retrieved 2021-03-12.
- ^ a b c Shabani, M. A.; Irannajad, M.; Azadmehr, A. R. (2012-09-01). "Investigation on leaching of malachite by citric acid". International Journal of Minerals, Metallurgy, and Materials. 19 (9): 782–786. doi:10.1007/s12613-012-0628-9. ISSN 1869-103X.
- ^ "Malachite". www.mine-engineer.com. Retrieved 2021-03-25.
- ^ Monjezi, M.; Shahriar, K.; Dehghani, H.; Samimi Namin, F. (2009-07-01). "Environmental impact assessment of open pit mining in Iran". Environmental Geology. 58 (1): 205–216. doi:10.1007/s00254-008-1509-4. ISSN 1432-0495.
- ^ a b c Salomons, W. (1995-01-01). "Environmental impact of metals derived from mining activities: Processes, predictions, prevention". Journal of Geochemical Exploration. Heavy Metal Aspects of Mining Pollution and Its Remediation. 52 (1): 5–23. doi:10.1016/0375-6742(94)00039-E. ISSN 0375-6742.
- ^ "Environmental Impact of Sulfuric Acid Leaching". www.savethesantacruzaquifer.info. Retrieved 2021-03-25.
- ^ Conard, Bruce R. (1992-06-01). "The role of hydrometallurgy in achieving sustainable development". Hydrometallurgy. Hydrometallurgy, Theory and Practice Proceedings of the Ernest Peters International Symposium. Part B. 30 (1): 1–28. doi:10.1016/0304-386X(92)90074-A. ISSN 0304-386X.